Implications of MOLA Global Roughness, Statistics, and Topography
NASA Technical Reports Server (NTRS)
Aharonson, O.; Zuber, M. T.; Neumann, G. A.
1999-01-01
New insights are emerging as the ongoing high-quality measurements of the Martian surface topography by Mars Orbiter Laser Altimeter (MOLA) on board the Mars Global Surveyor (MGS) spacecraft increase in coverage, resolution, and diversity. For the first time, a global characterization of the statistical properties of topography is possible. The data were collected during the aerobreaking hiatus, science phasing, and mapping orbits of MGS, and have a resolution of 300-400 m along track, a range resolution of 37.5 cm, a range precision of 1-10 m for surface slopes up to 30 deg., and an absolute accuracy of topography of 13 m. The spacecraft's orbit inclination dictates that nadir observations have latitude coverage of about 87.1S to 87.1N; the addition of observations obtained during a period of off-nadir pointing over the north pole extended coverage to 90N. Additional information is contained in the original extended abstract.
NASA Technical Reports Server (NTRS)
Rossow, William B. (Principal Investigator)
Since 1983 an international group of institutions has collected and analyzed satellite radiance measurements from up to five geostationary and two polar orbiting satellites to infer the global distribution of cloud properties and their diurnal, seasonal and interannual variations. The primary focus of the first phase of the project (1983-1995) was the elucidation of the role of clouds in the radiation budget (top of the atmosphere and surface). In the second phase of the project (1995 onwards) the analysis also concerns improving understanding of clouds in the global hydrological cycle. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=112 Km; Longitude_Resolution=112 Km; Temporal_Resolution=5-day].
A Global Map of Thermal Inertia from Mars Global Surveyor Mapping-Mission Data
NASA Technical Reports Server (NTRS)
Mellon, M. T.; Kretke, K. A.; Smith, M. D.; Pelkey, S. M.
2002-01-01
TES (thermal emission spectrometry) has obtained high spatial resolution surface temperature observations from which thermal inertia has been derived. Seasonal coverage of these data now provides a nearly global view of Mars, including the polar regions, at high resolution. Additional information is contained in the original extended abstract.
NASA Technical Reports Server (NTRS)
Figueredo, P. H.; Tanaka, K.; Senske, D.; Greeley, R.
2003-01-01
Knowledge of the geology, style and time history of crustal processes on the icy Galilean satellites is necessary to understanding how these bodies formed and evolved. Data from the Galileo mission have provided a basis for detailed geologic and geo- physical analysis. Due to constrained downlink, Galileo Solid State Imaging (SSI) data consisted of global coverage at a -1 km/pixel ground sampling and representative, widely spaced regional maps at -200 m/pixel. These two data sets provide a general means to extrapolate units identified at higher resolution to lower resolution data. A sampling of key sites at much higher resolution (10s of m/pixel) allows evaluation of processes on local scales. We are currently producing the first global geological map of Europa using Galileo global and regional-scale data. This work is demonstrating the necessity and utility of planet-wide contiguous image coverage at global, regional, and local scales.
Global Coverage from Ad-Hoc Constellations in Rideshare Orbits
NASA Technical Reports Server (NTRS)
Ellis, Armin; Mercury, Michael; Brown, Shannon
2012-01-01
A promising area of small satellite development is in providing higher temporal resolution than larger satellites. Traditional constellations have required specific orbits and dedicated launch vehicles. In this paper we discuss an alternative architecture in which the individual elements of the constellation are launched as rideshare opportunities. We compare the coverage of such an ad-hoc constellation with more traditional constellations. Coverage analysis is based on actual historical data from rideshare opportunities. Our analysis includes ground coverage and temporal revisits for Polar, Tropics, Temperate, and Global regions, comparing ad-hoc and Walker constellation.
Hydrologic Derivatives for Modeling and Analysis—A new global high-resolution database
Verdin, Kristine L.
2017-07-17
The U.S. Geological Survey has developed a new global high-resolution hydrologic derivative database. Loosely modeled on the HYDRO1k database, this new database, entitled Hydrologic Derivatives for Modeling and Analysis, provides comprehensive and consistent global coverage of topographically derived raster layers (digital elevation model data, flow direction, flow accumulation, slope, and compound topographic index) and vector layers (streams and catchment boundaries). The coverage of the data is global, and the underlying digital elevation model is a hybrid of three datasets: HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales), GMTED2010 (Global Multi-resolution Terrain Elevation Data 2010), and the SRTM (Shuttle Radar Topography Mission). For most of the globe south of 60°N., the raster resolution of the data is 3 arc-seconds, corresponding to the resolution of the SRTM. For the areas north of 60°N., the resolution is 7.5 arc-seconds (the highest resolution of the GMTED2010 dataset) except for Greenland, where the resolution is 30 arc-seconds. The streams and catchments are attributed with Pfafstetter codes, based on a hierarchical numbering system, that carry important topological information. This database is appropriate for use in continental-scale modeling efforts. The work described in this report was conducted by the U.S. Geological Survey in cooperation with the National Aeronautics and Space Administration Goddard Space Flight Center.
NASA Astrophysics Data System (ADS)
Biastoch, Arne; Sein, Dmitry; Durgadoo, Jonathan V.; Wang, Qiang; Danilov, Sergey
2018-01-01
Many questions in ocean and climate modelling require the combined use of high resolution, global coverage and multi-decadal integration length. For this combination, even modern resources limit the use of traditional structured-mesh grids. Here we compare two approaches: A high-resolution grid nested into a global model at coarser resolution (NEMO with AGRIF) and an unstructured-mesh grid (FESOM) which allows to variably enhance resolution where desired. The Agulhas system around South Africa is used as a testcase, providing an energetic interplay of a strong western boundary current and mesoscale dynamics. Its open setting into the horizontal and global overturning circulations also requires global coverage. Both model configurations simulate a reasonable large-scale circulation. Distribution and temporal variability of the wind-driven circulation are quite comparable due to the same atmospheric forcing. However, the overturning circulation differs, owing each model's ability to represent formation and spreading of deep water masses. In terms of regional, high-resolution dynamics, all elements of the Agulhas system are well represented. Owing to the strong nonlinearity in the system, Agulhas Current transports of both configurations and in comparison with observations differ in strength and temporal variability. Similar decadal trends in Agulhas Current transport and Agulhas leakage are linked to the trends in wind forcing.
AVHRR for monitoring global tropical deforestation
NASA Technical Reports Server (NTRS)
Malingreau, J. P.; Laporte, N.; Tucker, C. J.
1989-01-01
Advanced Very High Resolution Radiometer (AVHRR) data have been used to assess the dynamics of forest trnsformations in three parts of the tropical belt. A large portion of the Amazon Basin has been systematically covered by Local Area Coverage (LAC) data in the 1985-1987 period. The analysis of the vegetation index and thermal data led to the identification and measurement of large areas of active deforestation. The Kalimantan/Borneo forest fires were monitored and their impact was evaluated using the Global Area Coverage (GAC) 4 km resolution data. Finally, High Resolution Picture Transmission (HRPT) data have provided preliminary information on current activities taking place at the boundary between the savanna and the forest in the Southern part of West Africa. The AVHRR approach is found to be a highly valuable means for carrying out deforestation assessments in regional and global perspectives.
Hain, Christopher R; Anderson, Martha C
2017-10-16
Observations of land surface temperature (LST) are crucial for the monitoring of surface energy fluxes from satellite. Methods that require high temporal resolution LST observations (e.g., from geostationary orbit) can be difficult to apply globally because several geostationary sensors are required to attain near-global coverage (60°N to 60°S). While these LST observations are available from polar-orbiting sensors, providing global coverage at higher spatial resolutions, the temporal sampling (twice daily observations) can pose significant limitations. For example, the Atmosphere Land Exchange Inverse (ALEXI) surface energy balance model, used for monitoring evapotranspiration and drought, requires an observation of the morning change in LST - a quantity not directly observable from polar-orbiting sensors. Therefore, we have developed and evaluated a data-mining approach to estimate the mid-morning rise in LST from a single sensor (2 observations per day) of LST from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on the Aqua platform. In general, the data-mining approach produced estimates with low relative error (5 to 10%) and statistically significant correlations when compared against geostationary observations. This approach will facilitate global, near real-time applications of ALEXI at higher spatial and temporal coverage from a single sensor than currently achievable with current geostationary datasets.
Mars Global Coverage by Context Camera on MRO
2017-03-29
In early 2017, after more than a decade of observing Mars, the Context Camera (CTX) on NASA's Mars Reconnaissance Orbiter (MRO) surpassed 99 percent coverage of the entire planet. This mosaic shows that global coverage. No other camera has ever imaged so much of Mars in such high resolution. The mosaic offers a resolution that enables zooming in for more detail of any region of Mars. It is still far from the full resolution of individual CTX observations, which can reveal the shapes of features smaller than the size of a tennis court. As of March 2017, the Context Camera has taken about 90,000 images since the spacecraft began examining Mars from orbit in late 2006. In addition to covering 99.1 percent of the surface of Mars at least once, this camera has observed more than 60 percent of Mars more than once, checking for changes over time and providing stereo pairs for 3-D modeling of the surface. http://photojournal.jpl.nasa.gov/catalog/PIA21488
The development and validation of command schedules for SeaWiFS
NASA Astrophysics Data System (ADS)
Woodward, Robert H.; Gregg, Watson W.; Patt, Frederick S.
1994-11-01
An automated method for developing and assessing spacecraft and instrument command schedules is presented for the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) project. SeaWiFS is to be carried on the polar-orbiting SeaStar satellite in 1995. The primary goal of the SeaWiFS mission is to provide global ocean chlorophyll concentrations every four days by employing onboard recorders and a twice-a-day data downlink schedule. Global Area Coverage (GAC) data with about 4.5 km resolution will be used to produce the global coverage. Higher resolution (1.1 km resolution) Local Area Coverage (LAC) data will also be recorded to calibrate the sensor. In addition, LAC will be continuously transmitted from the satellite and received by High Resolution Picture Transmission (HRPT) stations. The methods used to generate commands for SeaWiFS employ numerous hierarchical checks as a means of maximizing coverage of the Earth's surface and fulfilling the LAC data requirements. The software code is modularized and written in Fortran with constructs to mirror the pre-defined mission rules. The overall method is specifically developed for low orbit Earth-observing satellites with finite onboard recording capabilities and regularly scheduled data downlinks. Two software packages using the Interactive Data Language (IDL) for graphically displaying and verifying the resultant command decisions are presented. Displays can be generated which show portions of the Earth viewed by the sensor and spacecraft sub-orbital locations during onboard calibration activities. An IDL-based interactive method of selecting and testing LAC targets and calibration activities for command generation is also discussed.
MISR Level 2 TOA/Cloud Classifier parameters (MIL2TCCL_V2)
NASA Technical Reports Server (NTRS)
Diner, David J. (Principal Investigator)
The TOA/Cloud Classifiers contain the Angular Signature Cloud Mask (ASCM), a scene classifier calculated using support vector machine technology (SVM) both of which are on a 1.1 km grid, and cloud fractions at 17.6 km resolution that are available in different height bins (low, middle, high) and are also calculated on an angle-by-angle basis. [Location=GLOBAL] [Temporal_Coverage: Start_Date=2000-02-24; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=17.6 km; Longitude_Resolution=17.6 km; Horizontal_Resolution_Range=10 km - < 50 km or approximately .09 degree - < .5 degree; Temporal_Resolution=about 15 orbits/day; Temporal_Resolution_Range=Daily - < Weekly, Daily - < Weekly].
Satellite Remote Sensing of Cirrus: An Overview
NASA Technical Reports Server (NTRS)
Minnis, Patrick
1998-01-01
The determination of cirrus properties over relatively large spatial and temporal scales will, in most instances, require the use of satellite data. Global coverage, at resolutions as high as several meters are attainable with Landsat, while temporal coverage at 1-min intervals is now available with the latest Geostationary Operational Environmental Satellite (GOES) imagers. Cirrus can be analyzed via interpretation of the radiation that they reflect or emit over a wide range of the electromagnetic spectrum. Many of these spectra and high-resolution satellite data can be used to understand certain aspects of cirrus clouds in particular situations. Production of a global climatology of cirrus clouds, however, requires compromises in spatial, temporal, and spectral coverage. This paper summarizes the state of the art and the potential for future passive remote sensing systems for both understanding cirrus formation and acquiring sufficient statistics to constrain and refine weather and climate models.
Global Magellan-image map of Venus at full resolution
NASA Technical Reports Server (NTRS)
Kirk, R. L.; Edwards, K. B.; Morgan, H. F.; Soderblom, L. A.; Stoewe, T. L.
1993-01-01
During its first 243-day mapping cycle, the Magellan spacecraft succeeded in imaging 84 percent of the surface of Venus at resolutions on the order of 100 meters; subsequent cycles have increased the total coverage to over 97 percent and provided redundant coverage of much of the planet with differing viewing geometries. Unfortunately, this full-resolution global dataset is in the form of thousands of individual orbit tracks (F-BIDR's) whose length-to-width ratio of nearly 1000:1 makes them minimally useful unless mosaicked. The Magellan project produced full-resolution mosaics (F-MIDR's) only for selected regions on the planet, whereas a global set of mosaics was made only at threefold degraded resolution (C1-MIDR's). Furthermore, although the F-MIDR's, which are approximately equidimensional, are much better suited for scientific interpretation than the F-BIDR's, they are still an unwieldy dataset: over 1500 quadrangles, each showing a region only about 600 km on a side, would be required to cover the entire planet. The USGS has therefore undertaken to produce and distribute a global, full resolution set of mosaics of the Magellan image data in a format that will be efficient for both hardcopy and digital use. The initial motivation was that it would provide an efficient means of verifying the integrity of the F-BIDR's to be archived on computer-compatible tape at the USGS Flagstaff facility. However, the resulting product, known as the FMAP, should also serve as an important resource for future scientific interpretation. It will offer several advantages beyond global coverage at full resolution. The first, alluded to above, is its division of the planet's surface to minimize the number of quadrangles and maximize their area, subject to the limits on the number of pixels imposed by state-of-the-art digital recording media and hardcopy output devices. The second, the use of improved 'cosmetic' processing techniques, will greatly reduce tonal discontinuities between component F-BIDR's in the FMAP compared to the standard Magellan mosaic products. Finally, wherever possible, the FMAP will incorporate data that were unavailable (e.g., because of processing delays) when the standard MIDR products were created, as well as data that were reprocessed to improve their radiometric or geometric quality.
Landsat Data Continuity Mission
,
2012-01-01
The Landsat Data Continuity Mission (LDCM) is a partnership formed between the National Aeronautics and Space Administration (NASA) and the U.S. Geological Survey (USGS) to place the next Landsat satellite in orbit in January 2013. The Landsat era that began in 1972 will become a nearly 41-year global land record with the successful launch and operation of the LDCM. The LDCM will continue the acquisition, archiving, and distribution of multispectral imagery affording global, synoptic, and repetitive coverage of the Earth's land surfaces at a scale where natural and human-induced changes can be detected, differentiated, characterized, and monitored over time. The mission objectives of the LDCM are to (1) collect and archive medium resolution (30-meter spatial resolution) multispectral image data affording seasonal coverage of the global landmasses for a period of no less than 5 years; (2) ensure that LDCM data are sufficiently consistent with data from the earlier Landsat missions in terms of acquisition geometry, calibration, coverage characteristics, spectral characteristics, output product quality, and data availability to permit studies of landcover and land-use change over time; and (3) distribute LDCM data products to the general public on a nondiscriminatory basis at no cost to the user.
NASA Astrophysics Data System (ADS)
Yang, W.; Min, M.; Bai, Y.; Lynnes, C.; Holloway, D.; Enloe, Y.; di, L.
2008-12-01
In the past few years, there have been growing interests, among major earth observing satellite (EOS) data providers, in serving data through the interoperable Web Coverage Service (WCS) interface protocol, developed by the Open Geospatial Consortium (OGC). The interface protocol defined in WCS specifications allows client software to make customized requests of multi-dimensional EOS data, including spatial and temporal subsetting, resampling and interpolation, and coordinate reference system (CRS) transformation. A WCS server describes an offered coverage, i.e., a data product, through a response to a client's DescribeCoverage request. The description includes the offered coverage's spatial/temporal extents and resolutions, supported CRSs, supported interpolation methods, and supported encoding formats. Based on such information, a client can request the entire or a subset of coverage in any spatial/temporal resolutions and in any one of the supported CRSs, formats, and interpolation methods. When implementing a WCS server, a data provider has different approaches to present its data holdings to clients. One of the most straightforward, and commonly used, approaches is to offer individual physical data files as separate coverages. Such implementation, however, will result in too many offered coverages for large data holdings and it also cannot fully present the relationship among different, but spatially and/or temporally associated, data files. It is desirable to disconnect offered coverages from physical data files so that the former is more coherent, especially in spatial and temporal domains. Therefore, some servers offer one single coverage for a set of spatially coregistered time series data files such as a daily global precipitation coverage linked to many global single- day precipitation files; others offer one single coverage for multiple temporally coregistered files together forming a large spatial extent. In either case, a server needs to assemble an output coverage real-time by combining potentially large number of physical files, which can be operationally difficult. The task becomes more challenging if an offered coverage involves spatially and temporally un-registered physical files. In this presentation, we will discuss issues and lessons learned in providing NASA's AIRS Level 2 atmospheric products, which are in satellite swath CRS and in 6-minute segment granule files, as virtual global coverages. We"ll discuss the WCS server's on- the-fly georectification, mosaicking, quality screening, performance, and scalability.
Surface Meteorology and Solar Energy (SSE) Data Release 5.1
NASA Technical Reports Server (NTRS)
Stackhouse, Paul W. (Principal Investigator)
The Surface meteorology and Solar Energy (SSE) data set contains over 200 parameters formulated for assessing and designing renewable energy systems.The SSE data set is formulated from NASA satellite- and reanalysis-derived insolation and meteorological data for the 10-year period July 1983 through June 1993. Results are provided for 1 degree latitude by 1 degree longitude grid cells over the globe. Average daily and monthly measurements for 1195 World Radiation Data Centre ground sites are also available. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=1993-06-30] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree].
NASA Astrophysics Data System (ADS)
Reed, P. M.; Chaney, N.; Herman, J. D.; Wood, E. F.; Ferringer, M. P.
2015-12-01
This research represents a multi-institutional collaboration between Cornell University, The Aerospace Corporation, and Princeton University that has completed a Petascale diagnostic assessment of the current 10 satellite missions providing rainfall observations. Our diagnostic assessment has required four core tasks: (1) formally linking high-resolution astrodynamics design and coordination of space assets with their global hydrological impacts within a Petascale "many-objective" global optimization framework, (2) developing a baseline diagnostic evaluation of a 1-degree resolution global implementation of the Variable Infiltration Capacity (VIC) model to establish the required satellite observation frequencies and coverage to maintain acceptable global flood forecasts, (3) evaluating the limitations and vulnerabilities of the full suite of current satellite precipitation missions including the recently approved Global Precipitation Measurement (GPM) mission, and (4) conceptualizing the next generation spaced-based platforms for water cycle observation. Our team exploited over 100 Million hours of computing access on the 700,000+ core Blue Waters machine to radically advance our ability to discover and visualize key system tradeoffs and sensitivities. This project represents to our knowledge the first attempt to develop a 10,000 member Monte Carlo global hydrologic simulation at one degree resolution that characterizes the uncertain effects of changing the available frequencies of satellite precipitation on drought and flood forecasts. The simulation—optimization components of the work have set a theoretical baseline for the best possible frequencies and coverages for global precipitation given unlimited investment, broad international coordination in reconfiguring existing assets, and new satellite constellation design objectives informed directly by key global hydrologic forecasting requirements. Our research poses a step towards realizing the integrated global water cycle observatory long sought by the World Climate Research Programme, which has to date eluded the world's space agencies.
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly TOA/Surface Averages (SRBAVG) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SRBAVG is also produced for combinations of scanner instruments. The monthly average regional flux is estimated using diurnal models and the 1-degree regional fluxes at the hour of observation from the CERES SFC product. A second set of monthly average fluxes are estimated using concurrent diurnal information from geostationary satellites. These fluxes are given for both clear-sky and total-sky scenes and are spatially averaged from 1-degree regions to 1-degree zonal averages and a global average. For each region, the SRBAVG also contains hourly average fluxes for the month and an overall monthly average. The cloud properties from SFC are column averaged and are included on the SRBAVG. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-02-01; Stop_Date=2003-02-28] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly TOA/Surface Averages (SRBAVG) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SRBAVG is also produced for combinations of scanner instruments. The monthly average regional flux is estimated using diurnal models and the 1-degree regional fluxes at the hour of observation from the CERES SFC product. A second set of monthly average fluxes are estimated using concurrent diurnal information from geostationary satellites. These fluxes are given for both clear-sky and total-sky scenes and are spatially averaged from 1-degree regions to 1-degree zonal averages and a global average. For each region, the SRBAVG also contains hourly average fluxes for the month and an overall monthly average. The cloud properties from SFC are column averaged and are included on the SRBAVG. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-02-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly TOA/Surface Averages (SRBAVG) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SRBAVG is also produced for combinations of scanner instruments. The monthly average regional flux is estimated using diurnal models and the 1-degree regional fluxes at the hour of observation from the CERES SFC product. A second set of monthly average fluxes are estimated using concurrent diurnal information from geostationary satellites. These fluxes are given for both clear-sky and total-sky scenes and are spatially averaged from 1-degree regions to 1-degree zonal averages and a global average. For each region, the SRBAVG also contains hourly average fluxes for the month and an overall monthly average. The cloud properties from SFC are column averaged and are included on the SRBAVG. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-02-01; Stop_Date=2003-02-28] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly TOA/Surface Averages (SRBAVG) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SRBAVG is also produced for combinations of scanner instruments. The monthly average regional flux is estimated using diurnal models and the 1-degree regional fluxes at the hour of observation from the CERES SFC product. A second set of monthly average fluxes are estimated using concurrent diurnal information from geostationary satellites. These fluxes are given for both clear-sky and total-sky scenes and are spatially averaged from 1-degree regions to 1-degree zonal averages and a global average. For each region, the SRBAVG also contains hourly average fluxes for the month and an overall monthly average. The cloud properties from SFC are column averaged and are included on the SRBAVG. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-02-01; Stop_Date=2004-05-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
Landsat Data Continuity Mission
,
2007-01-01
The Landsat Data Continuity Mission (LDCM) is a partnership between the National Aeronautics and Space Administration (NASA) and the U.S. Geological Survey (USGS) to place the next Landsat satellite in orbit by late 2012. The Landsat era that began in 1972 will become a nearly 45-year global land record with the successful launch and operation of the LDCM. The LDCM will continue the acquisition, archival, and distribution of multispectral imagery affording global, synoptic, and repetitive coverage of the Earth's land surfaces at a scale where natural and human-induced changes can be detected, differentiated, characterized, and monitored over time. The mission objectives of the LDCM are to (1) collect and archive medium resolution (circa 30-m spatial resolution) multispectral image data affording seasonal coverage of the global landmasses for a period of no less than 5 years; (2) ensure that LDCM data are sufficiently consistent with data from the earlier Landsat missions, in terms of acquisition geometry, calibration, coverage characteristics, spectral characteristics, output product quality, and data availability to permit studies of land-cover and land-use change over time; and (3) distribute LDCM data products to the general public on a nondiscriminatory basis and at a price no greater than the incremental cost of fulfilling a user request. Distribution of LDCM data over the Internet at no cost to the user is currently planned.
Spectral Resolution and Coverage Impact on Advanced Sounder Information Content
NASA Technical Reports Server (NTRS)
Larar, Allen M.; Liu, Xu; Zhou, Daniel K.; Smith, William L.
2010-01-01
Advanced satellite sensors are tasked with improving global measurements of the Earth s atmosphere, clouds, and surface to enable enhancements in weather prediction, climate monitoring capability, and environmental change detection. Achieving such measurement improvements requires instrument system advancements. This presentation focuses on the impact of spectral resolution and coverage changes on remote sensing system information content, with a specific emphasis on thermodynamic state and trace species variables obtainable from advanced atmospheric sounders such as the Infrared Atmospheric Sounding Interferometer (IASI) and Cross-track Infrared Sounder (CrIS) systems on the MetOp and NPP/NPOESS series of satellites. Key words: remote sensing, advanced sounders, information content, IASI, CrIS
High Spatial Resolution Europa Coverage by the Galileo Near Infrared Mapping Spectrometer NIMS
1998-03-26
NASA Galileo spacecraft, which was used to map the mineral and ice properties over the surfaces of the Jovian moons, producing global spectral images for small selected regions on the satellites in 1996-97.
Platinum replica electron microscopy: Imaging the cytoskeleton globally and locally.
Svitkina, Tatyana M
2017-05-01
Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the "comfort zones" of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. Copyright © 2017 Elsevier Ltd. All rights reserved.
Platinum Replica Electron Microscopy: Imaging the Cytoskeleton Globally and Locally
SVITKINA, Tatyana M.
2017-01-01
Structural studies reveal how smaller components of a system work together as a whole. However, combining high resolution of details with full coverage of the whole is challenging. In cell biology, light microscopy can image many cells in their entirety, but at a lower resolution, whereas electron microscopy affords very high resolution, but usually at the expense of the sample size and coverage. Structural analyses of the cytoskeleton are especially demanding, because cytoskeletal networks are unresolvable by light microscopy due to their density and intricacy, whereas their proper preservation is a challenge for electron microscopy. Platinum replica electron microscopy can uniquely bridge the gap between the “comfort zones” of light and electron microscopy by allowing high resolution imaging of the cytoskeleton throughout the entire cell and in many cells in the population. This review describes the principles and applications of platinum replica electron microscopy for studies of the cytoskeleton. PMID:28323208
DOE Office of Scientific and Technical Information (OSTI.GOV)
Molenkamp, C.R.; Grossman, A.
1999-12-20
A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show thatmore » reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.« less
Science Objectives of EOS-Aura's Ozone Monitoring Instrument (OMI)
NASA Technical Reports Server (NTRS)
Levelt, P. F.; Veefkind, J. P.; Stammes, P.; Hilsenrath, E.; Bhartia, P. K.; Chance, K. V.; Leppelmeier, G. W.; Maelkki, A.; Bhartia, Pawan (Technical Monitor)
2002-01-01
OMI is a UV/VIS nadir solar backscatter spectrograph, which provides near global coverage in one day with a spatial resolution of 13 x 24 sq km. OMI is a new instrument, with a heritage from the European satellite instruments GOME, GOMOS and SCIAMACHY. OMI's unique capabilities for measuring important trace gases with a small footprint and daily global coverage, in conjunction with the other Aura instruments, will make a major contribution to our understanding of stratospheric and tropospheric chemistry and climate change. OMI will measure solar irradiance and Earth radiances in the wavelength range of 270 to 500 nm with spectral resolution of about 0.5 nm and a spectral sampling of about 2-3 per FWHM. From these observations, total columns of O3, NO2, BrO and SO2 will be derived from the back-scattered solar radiance using differential absorption spectroscopy (DOAS). The TOMS total ozone record will also be continued by employing the well established TOMS algorithm. Because of the high accuracy and spatial resolution of the measurements, a good estimate of tropospheric amounts of ozone and NO2 are expected. Ozone profiles will be derived using the optimal estimation method. The spectral aerosol optical depth will be determined from measurements between 340 and 500 nm. This will provide information on aerosol concentration, aerosol size distribution and aerosol type. This wavelength range makes it possible to retrieve aerosol information over both land and sea. OMI observations will also allow retrievals of cloud coverage and cloud heights. From these products, the UV-B flux at the surface can then be derived with high spatial resolution.
NASA Astrophysics Data System (ADS)
Levelt, Pieternel; Veefkind, Pepijn; Bhartia, Pawan; Joiner, Joanna; Tamminen, Johanna; OMI Science Team
2014-05-01
On July 15, 2004 Ozone Monitoring Instrument (OMI) was successfully launched from the Vandenberg military air force basis in California, USA, on NASA's EOS-Aura spacecraft. OMI is the first of a new generation of UV/VIS nadir solar backscatter imaging spectrometers, which provides nearly global coverage in one day with an unprecedented spatial resolution of 13 x 24 km2. OMI measures solar irradiance and Earth radiances in the wavelength range of 270 to 500 nm with a spectral resolution of about 0.5 nm. OMI is designed and built by the Netherlands and Finland and is also a third party mission of ESA. The major step that was made in the OMI instrument compared to its predecessors is the use of 2-dimensional detector arrays (CCDs) in a highly innovative small optical design. These innovations enable the combination of a high spatial resolution and a good spectral resolution with daily global coverage. OMI measures a range of trace gases (O3, NO2, SO2, HCHO, BrO, OClO, H2O), clouds and aerosols. Albeit OMI is already 5 years over its design lifetime, the instrument is still fully operational. The successor of OMI is TROPOMI (TROPOspheric Monitoring Instrument) on the Copernicus Sentinel-5 precursor mission, planned for launch in 2015. OMI's unique capabilities rely in measuring tropospheric trace gases with a small footprint and daily global coverage. The unprecedented spatial resolution of the instrument revealed for the first time tropospheric pollution maps on a daily basis with urban scale resolution leading to improved air quality forecasts. The OMI measurements also improve our understanding of air quality and the interaction between air quality and climate change by combining measurements of air pollutants and aerosols. In recent years the data are also used for obtaining high-resolution global emission maps using inverse modelling or related techniques, challenging the bottom-up inventories based emission maps. In addition to scientific research, OMI also contributes to several operational services, including volcanic plume warning systems for aviation, UV forecasts and the air quality forecasts. In this invited talk an overview will be given of unique findings and new scientific results based on OMI data over the last 10 years and which unique OMI instrument features are recurring in the new generation of UV/VIS satellite instrumentation in Europe, USA and Asia.
The moderate resolution imaging spectrometer (MODIS) science and data system requirements
NASA Technical Reports Server (NTRS)
Ardanuy, Philip E.; Han, Daesoo; Salomonson, Vincent V.
1991-01-01
The Moderate Resolution Imaging Spectrometer (MODIS) has been designated as a facility instrument on the first NASA polar orbiting platform as part of the Earth Observing System (EOS) and is scheduled for launch in the late 1990s. The near-global daily coverage of MODIS, combined with its continuous operation, broad spectral coverage, and relatively high spatial resolution, makes it central to the objectives of EOS. The development, implementation, production, and validation of the core MODIS data products define a set of functional, performance, and operational requirements on the data system that operate between the sensor measurements and the data products supplied to the user community. The science requirements guiding the processing of MODIS data are reviewed, and the aspects of an operations concept for the production of data products from MODIS for use by the scientific community are discussed.
OMEGA: Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité
NASA Astrophysics Data System (ADS)
Bibring, J.-P.; Soufflot, A.; Berthé, M.; Langevin, Y.; Gondet, B.; Drossart, P.; Bouyé, M.; Combes, M.; Puget, P.; Semery, A.; Bellucci, G.; Formisano, V.; Moroz, V.; Kottsov, V.; Bonello, G.; Erard, S.; Forni, O.; Gendrin, A.; Manaud, N.; Poulet, F.; Poulleau, G.; Encrenaz, T.; Fouchet, T.; Melchiori, R.; Altieri, F.; Ignatiev, N.; Titov, D.; Zasova, L.; Coradini, A.; Capacionni, F.; Cerroni, P.; Fonti, S.; Mangold, N.; Pinet, P.; Schmitt, B.; Sotin, C.; Hauber, E.; Hoffmann, H.; Jaumann, R.; Keller, U.; Arvidson, R.; Mustard, J.; Forget, F.
2004-08-01
The OMEGA visible and near-IR mapping spectrometer will reveal the mineralogical and molecular composition of the surface and atmosphere of Mars through the spectral analysis of the diffused solar light and surface thermal emission. It will provide global coverage at medium resolution (2-5 km) for altitudes from 1500 km to 4000 km, and high-resolution (<350 m) spectral images of selected areas.
NASA Technical Reports Server (NTRS)
Joiner, J.; Gaunter, L.; Lindstrot, R.; Voigt, M.; Vasilkov, A. P.; Middleton, E. M.; Huemmrich, K. F.; Yoshida, Y.; Frankenberg, C.
2013-01-01
Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2). The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT). GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0.5 deg × 0.5 deg. We also show some significant differences between fluorescence and coincident normalized difference vegetation indices (NDVI) retrievals.
NASA Technical Reports Server (NTRS)
Joiner, J.; Guanter, L.; Lindstrot, R.; Voigt, M.; Vasilkov, A. P.; Middleton, E. M.; Huemmrich, K. F.; Yoshida, Y.; Frankenberg, C.
2013-01-01
Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2). The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT). GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0.5 0.5. We also show some significant differences between fluorescence and coincident normalized difference vegetation indices (NDVI) retrievals.
CERES Clouds and Radiative Swath (CRS) data in HDF. (CER_CRS_Terra-FM2-MODIS_Edition2B)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Clouds and Radiative Swath (CRS) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The CRS contains all of the CERES SSF product data. For each CERES footprint on the SSF the CRS also contains vertical flux profiles evaluated at four levels in the atmosphere: the surface, 500-, 70-, and 1-hPa. The CRS fluxes and cloud parameters are adjusted for consistency with a radiative transfer model and adjusted fluxes are evaluated at the four atmospheric levels for both clear-sky and total-sky. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2001-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
CERES Clouds and Radiative Swath (CRS) data in HDF (CER_CRS_TRMM-PFM-VIRS_Edition2C)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Clouds and Radiative Swath (CRS) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The CRS contains all of the CERES SSF product data. For each CERES footprint on the SSF the CRS also contains vertical flux profiles evaluated at four levels in the atmosphere: the surface, 500-, 70-, and 1-hPa. The CRS fluxes and cloud parameters are adjusted for consistency with a radiative transfer model and adjusted fluxes are evaluated at the four atmospheric levels for both clear-sky and total-sky. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
CERES Clouds and Radiative Swath (CRS) data in HDF. (CER_CRS_Terra-FM2-MODIS_Edition2A
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Clouds and Radiative Swath (CRS) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The CRS contains all of the CERES SSF product data. For each CERES footprint on the SSF the CRS also contains vertical flux profiles evaluated at four levels in the atmosphere: the surface, 500-, 70-, and 1-hPa. The CRS fluxes and cloud parameters are adjusted for consistency with a radiative transfer model and adjusted fluxes are evaluated at the four atmospheric levels for both clear-sky and total-sky. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2001-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
A search for life on earth at 100 meter resolution.
NASA Technical Reports Server (NTRS)
Sagan, C.; Wallace, D.
1971-01-01
Study of several thousand photos indicating that about 0.01 of Gemini and Apollo photographs of the earth at 100 m resolution reveal signs of life - rectangular arrays due to human agricultural and urban territoriality, roads, canals, jet contrails, and industrial pollution. Potential false positives - e.g., dunes, sand bars, jetstream clouds - abound. A curve is derived for the detectivity of contemporary life on earth, in a plot of ground resolution versus global coverage. A comparable biology on Mars would not have been detected by all observations of Mars through Mariner 7.
Palache, A; Abelin, A; Hollingsworth, R; Cracknell, W; Jacobs, C; Tsai, T; Barbosa, P
2017-08-24
There is no global monitoring system for influenza vaccination coverage, making it difficult to assess progress towards the 2003 World Health Assembly (WHA) vaccination coverage target. In 2008, the IFPMA Influenza Vaccine Supply International Task Force (IVS) developed a survey method to assess the global distribution of influenza vaccine doses as a proxy for vaccination coverage rates. The latest dose distribution data for 2014 and 2015 was used to update previous analyses. Data were confidentially collected and aggregated by the IFPMA Secretariat, and combined with previous IFPMA IVS survey data (2004-2013). Data were available from 201 countries over the 2004-2015 period. A "hurdle" rate was defined as the number of doses required to reach 15.9% of the population in 2008. Overall, the number of distributed doses progressively increased between 2004 and 2011, driven by a 150% increase in AMRO, then plateaued. One percent fewer doses were distributed in 2015 than in 2011. Twenty-three countries were above the hurdle rate in 2015, compared to 15 in 2004, but distribution was highly uneven in and across all WHO regions. Three WHO regions (AMRO, EURO and WPRO) accounted for about 95% of doses distributed. But in EURO and WPRO, distribution rates in 2015 were only marginally higher than in 2004, and in EURO there was an overall downward trend in dose distribution. The vast majority of countries cannot meet the 2003WHA coverage targets and are inadequately prepared for a global influenza pandemic. With only 5% of influenza vaccine doses being distributed to 50% of the world's population, there is urgency to redress the gross inequities in disease prevention and in pandemic preparedness. The 2003WHA resolution must be reviewed and revised and a call issued for the renewed commitment of Member States to influenza vaccination coverage targets. Copyright © 2017. Published by Elsevier Ltd.
High Spatial Resolution Europa Coverage by the Galileo Near Infrared Mapping Spectrometer (NIMS)
NASA Technical Reports Server (NTRS)
1997-01-01
The NIMS instrument on the Galileo spacecraft, which is being used to map the mineral and ice properties over the surfaces of the Jovian moons, produces global spectral images at modest spatial resolution and high resolution spectral images for small selected regions on the satellites. This map illustrates the high resolution coverage of Europa obtained by NIMS through the April 1997 G7 orbit.
The areas covered are displayed on a Voyager-derived map. A good sampling of the dark trailing-side material (180 to 360 degrees) has been obtained, with less coverage of Europa's leading side.The false-color composites use red, green and blue to represent the infrared brightnesses at 0.7, 1.51 and 1.82 microns respectively. Considerable variations are evident and are related to the composition and sizes of the surface grains.The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.In need of combined topography and bathymetry DEM
NASA Astrophysics Data System (ADS)
Kisimoto, K.; Hilde, T.
2003-04-01
In many geoscience applications, digital elevation models (DEMs) are now more commonly used at different scales and greater resolution due to the great advancement in computer technology. Increasing the accuracy/resolution of the model and the coverage of the terrain (global model) has been the goal of users as mapping technology has improved and computers get faster and cheaper. The ETOPO5 (5 arc minutes spatial resolution land and seafloor model), initially developed in 1988 by Margo Edwards, then at Washington University, St. Louis, MO, has been the only global terrain model for a long time, and it is now being replaced by three new topographic and bathymetric DEMs, i.e.; the ETOPO2 (2 arc minutes spatial resolution land and seafloor model), the GTOPO30 land model with a spatial resolution of 30 arc seconds (c.a. 1km at equator) and the 'GEBCO 1-MINUTE GLOBAL BATHYMETRIC GRID' ocean floor model with a spatial resolution of 1 arc minute (c.a. 2 km at equator). These DEMs are products of projects through which compilation and reprocessing of existing and/or new datasets were made to meet user's new requirements. These ongoing efforts are valuable and support should be continued to refine and update these DEMs. On the other hand, a different approach to create a global bathymetric (seafloor) database exists. A method to estimate the seafloor topography from satellite altimetry combined with existing ships' conventional sounding data was devised and a beautiful global seafloor database created and made public by W.H. Smith and D.T. Sandwell in 1997. The big advantage of this database is the uniformity of coverage, i.e. there is no large area where depths are missing. It has a spatial resolution of 2 arc minute. Another important effort is found in making regional, not global, seafloor databases with much finer resolutions in many countries. The Japan Hydrographic Department has compiled and released a 500m-grid topography database around Japan, J-EGG500, in 1999. Although the coverage of this database is only a small portion of the Earth, the database has been highly appreciated in the academic community, and accepted in surprise by the general public when the database was displayed in 3D imagery to show its quality. This database could be rather smoothly combined with the finer land DEM of 250m spatial resolution (Japan250m.grd, K. Kisimoto, 2000). One of the most important applications of this combined DEM of topography and bathymetry is tsunami modeling. Understanding of the coastal environment, management and development of the coastal region are other fields in need of these data. There is, however, an important issue to consider when we create a combined DEM of topography and bathymetry in finer resolutions. The problem arises from the discrepancy of the standard datum planes or reference levels used for topographic leveling and bathymetric sounding. Land topography (altitude) is defined by leveling from the single reference point determined by average mean sea level, in other words, land height is measured from the geoid. On the other hand, depth charts are made based on depth measured from locally determined reference sea surface level, and this value of sea surface level is taken from the long term average of the lowest tidal height. So, to create a combined DEM of topography and bathymetry in very fine scale, we need to avoid this inconsistency between height and depth across the coastal region. Height and depth should be physically continuous relative to a single reference datum across the coast within such new high resolution DEMs. (N.B. Coast line is not equal to 'altitude-zero line' nor 'depth-zero line'. It is defined locally as the long term average of the highest tide level.) All of this said, we still need a lot of work on the ocean side. Global coverage with detailed bathymetric mapping is still poor. Seafloor imaging and other geophysical measurements/experiments should be organized and conducted internationally and interdisciplinary ways more than ever. We always need greater technological advancement and application of this technology in marine sciences, and more enthusiastic minds of seagoing researchers as well. Recent seafloor mapping technology/quality both in bathymetry and imagery is very promising and even favorably compared with the terrain mapping. We discuss and present on recent achievement and needs on the seafloor mapping using several most up-to-date global- and regional- DEMs available for science community at the poster session.
NASA Astrophysics Data System (ADS)
Barbarossa, Valerio; Huijbregts, Mark A. J.; Beusen, Arthur H. W.; Beck, Hylke E.; King, Henry; Schipper, Aafke M.
2018-03-01
Streamflow data is highly relevant for a variety of socio-economic as well as ecological analyses or applications, but a high-resolution global streamflow dataset is yet lacking. We created FLO1K, a consistent streamflow dataset at a resolution of 30 arc seconds (~1 km) and global coverage. FLO1K comprises mean, maximum and minimum annual flow for each year in the period 1960-2015, provided as spatially continuous gridded layers. We mapped streamflow by means of artificial neural networks (ANNs) regression. An ensemble of ANNs were fitted on monthly streamflow observations from 6600 monitoring stations worldwide, i.e., minimum and maximum annual flows represent the lowest and highest mean monthly flows for a given year. As covariates we used the upstream-catchment physiography (area, surface slope, elevation) and year-specific climatic variables (precipitation, temperature, potential evapotranspiration, aridity index and seasonality indices). Confronting the maps with independent data indicated good agreement (R2 values up to 91%). FLO1K delivers essential data for freshwater ecology and water resources analyses at a global scale and yet high spatial resolution.
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly Gridded TOA/Surface Fluxes and Clouds (SFC) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SFC is also produced for combinations of scanner instruments. All instantaneous shortwave, longwave, and window fluxes at the Top-of-the-Atmosphere (TOA) and surface from the CERES SSF product for a month are sorted by 1-degree spatial regions and by the local hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the SFC along with other flux statistics and scene information. These average fluxes are given for both clear-sky and total-sky scenes. The regional cloud properties are column averaged and are included on the SFC. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=100] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
The High Resolution Stereo Camera (HRSC): 10 Years of Imaging Mars
NASA Astrophysics Data System (ADS)
Jaumann, R.; Neukum, G.; Tirsch, D.; Hoffmann, H.
2014-04-01
The HRSC Experiment: Imagery is the major source for our current understanding of the geologic evolution of Mars in qualitative and quantitative terms.Imaging is required to enhance our knowledge of Mars with respect to geological processes occurring on local, regional and global scales and is an essential prerequisite for detailed surface exploration. The High Resolution Stereo Camera (HRSC) of ESA's Mars Express Mission (MEx) is designed to simultaneously map the morphology, topography, structure and geologic context of the surface of Mars as well as atmospheric phenomena [1]. The HRSC directly addresses two of the main scientific goals of the Mars Express mission: (1) High-resolution three-dimensional photogeologic surface exploration and (2) the investigation of surface-atmosphere interactions over time; and significantly supports: (3) the study of atmospheric phenomena by multi-angle coverage and limb sounding as well as (4) multispectral mapping by providing high-resolution threedimensional color context information. In addition, the stereoscopic imagery will especially characterize landing sites and their geologic context [1]. The HRSC surface resolution and the digital terrain models bridge the gap in scales between highest ground resolution images (e.g., HiRISE) and global coverage observations (e.g., Viking). This is also the case with respect to DTMs (e.g., MOLA and local high-resolution DTMs). HRSC is also used as cartographic basis to correlate between panchromatic and multispectral stereo data. The unique multi-angle imaging technique of the HRSC supports its stereo capability by providing not only a stereo triplet but also a stereo quintuplet, making the photogrammetric processing very robust [1, 3]. The capabilities for three dimensional orbital reconnaissance of the Martian surface are ideally met by HRSC making this camera unique in the international Mars exploration effort.
Determination of Earth outgoing radiation using a constellation of satellites
NASA Astrophysics Data System (ADS)
Gristey, Jake; Chiu, Christine; Gurney, Robert; Han, Shin-Chan; Morcrette, Cyril
2017-04-01
The outgoing radiation fluxes at the top of the atmosphere, referred to as Earth outgoing radiation (EOR), constitute a vital component of the Earth's energy budget. This EOR exhibits strong diurnal signatures and is inherently connected to the rapidly evolving scene from which the radiation originates, so our ability to accurately monitor EOR with sufficient temporal resolution and spatial coverage is crucial for weather and climate studies. Despite vast improvements in satellite observations in recent decades, achieving these criteria remains challenging from current measurements. A technology revolution in small satellites and sensor miniaturisation has created a new and exciting opportunity for a novel, viable and sustainable observation strategy from a constellation of satellites, capable of providing both global coverage and high temporal resolution simultaneously. To explore the potential of a constellation approach for observing EOR we perform a series of theoretical simulation experiments. Using the results from these simulation experiments, we will demonstrate a baseline constellation configuration capable of accurately monitoring global EOR at unprecedented temporal resolution. We will also show whether it is possible to reveal synoptic scale, fast evolving phenomena by applying a deconvolution technique to the simulated measurements. The ability to observe and understand the relationship between these phenomena and changes in EOR is of fundamental importance in constraining future warming of our climate system.
2015-07-25
Four images from NASA's New Horizons' Long Range Reconnaissance Imager (LORRI) were combined with color data from the Ralph instrument to create this global view of Pluto. (The lower right edge of Pluto in this view currently lacks high-resolution color coverage.) The images, taken when the spacecraft was 280,000 miles (450,000 kilometers) away, show features as small as 1.4 miles (2.2 kilometers), twice the resolution of the single-image view taken on July 13. http://photojournal.jpl.nasa.gov/catalog/PIA19857
A framework for global river flood risk assessment
NASA Astrophysics Data System (ADS)
Winsemius, H. C.; Van Beek, L. P. H.; Bouwman, A.; Ward, P. J.; Jongman, B.
2012-04-01
There is an increasing need for strategic global assessments of flood risks. Such assessments may be required by: (a) International Financing Institutes and Disaster Management Agencies to evaluate where, when, and which investments in flood risk mitigation are most required; (b) (re-)insurers, who need to determine their required coverage capital; and (c) large companies to account for risks of regional investments. In this contribution, we propose a framework for global river flood risk assessment. The framework combines coarse scale resolution hazard probability distributions, derived from global hydrological model runs (typical scale about 0.5 degree resolution) with high resolution estimates of exposure indicators. The high resolution is required because floods typically occur at a much smaller scale than the typical resolution of global hydrological models, and exposure indicators such as population, land use and economic value generally are strongly variable in space and time. The framework therefore estimates hazard at a high resolution ( 1 km2) by using a) global forcing data sets of the current (or in scenario mode, future) climate; b) a global hydrological model; c) a global flood routing model, and d) importantly, a flood spatial downscaling routine. This results in probability distributions of annual flood extremes as an indicator of flood hazard, at the appropriate resolution. A second component of the framework combines the hazard probability distribution with classical flood impact models (e.g. damage, affected GDP, affected population) to establish indicators for flood risk. The framework can be applied with a large number of datasets and models and sensitivities of such choices can be evaluated by the user. The framework is applied using the global hydrological model PCR-GLOBWB, combined with a global flood routing model. Downscaling of the hazard probability distributions to 1 km2 resolution is performed with a new downscaling algorithm, applied on a number of target regions. We demonstrate the use of impact models in these regions based on global GDP, population, and land use maps. In this application, we show sensitivities of the estimated risks with regard to the use of different climate input datasets, decisions made in the downscaling algorithm, and different approaches to establish distributed estimates of GDP and asset exposure to flooding.
NASA Astrophysics Data System (ADS)
Guanter, L.
2017-12-01
Sun-induced chlorophyll fluorescence (SIF) is an electromagnetic signal emitted by the chlorophyll-a of assimilating plants in the 650-850 nm spectral range. The SIF emission has a mechanistic link to photosynthesis and responds instantaneously to perturbations in environmental conditions such as light and water stress, which makes it a powerful proxy for plants' photosynthetic activity. Global measurements of SIF from space have been available since late 2011 from four different atmospheric satellite missions (chronologically, GOSAT, SCIAMACHY, GOME-2 and OCO-2). The potential of the derived SIF data sets to represent the photosynthetic activity of different ecosystems, including large crop belts worldwide, the Amazon rainforest and boreal evergreen forests has been demonstrated in the relatively short life-time of global SIF data. Despite the demonstrated potential of SIF data as a proxy for global terrestrial gross primary production, current observations are partly hampered by a coarse spatial resolution or the lack of spatial coverage. For this reason, great expectations are put on the upcoming TROPOMI instrument onboard the Copernicus' Sentinel 5-Precursor mission to be launched by mid-end of 2017. TROPOMI will provide daily global coverage with a spatial resolution between 3 and 7 km and continuous spectral coverage of the visible and near-infrared part of the spectrum. The recent selection of FLEX as the ESA Earth Explorer 8 to be launched around 2022 and several upcoming geostationary missions (TEMPO, Sentinel-4 and GeoCARB, covering Europe and the Americas) with potential for SIF retrievals complete an exciting near-future scenario for the monitoring of SIF from space. In this contribution, we will provide an overview of recent developments in the global monitoring of SIF and will introduce the near-future observational scenario with especial emphasis on TROPOMI and the geostationary missions to be launched in the coming years.
Doppler lidar for measurement of atmospheric wind fields
NASA Technical Reports Server (NTRS)
Menzies, Robert T.
1991-01-01
Measurements of wind fields in the earth's troposphere with daily global coverage is widely considered as a significant advance for forecasting and transport studies. For optimal use by NWP (Numerical Weather Prediction) models the horizontal and vertical resolutions should be approximately 100 km and 1 km, respectively. For boundary layer studies vertical resolution of a few hundred meters seems essential. Earth-orbiting Doppler lidar has a unique capability to measure global winds in the troposphere with the high vertical resolution required. The lidar approach depends on transmission of pulses with high spectral purity and backscattering from the atmospheric aerosol particles or layered clouds to provide a return signal. Recent field measurement campaigns using NASA research aircraft have resulted in collection of aerosol and cloud data which can be used to optimize the Doppler lidar instrument design and measurement strategy.
Terrestrial remote sensing science and algorithms planned for EOS/MODIS
Running, S. W.; Justice, C.O.; Salomonson, V.V.; Hall, D.; Barker, J.; Kaufmann, Y. J.; Strahler, Alan H.; Huete, A.R.; Muller, Jan-Peter; Vanderbilt, V.; Wan, Z.; Teillet, P.; Carneggie, David M. Geological Survey (U.S.) Ohlen
1994-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) will be the primary daily global monitoring sensor on the NASA Earth Observing System (EOS) satellites, scheduled for launch on the EOS-AM platform in June 1998 and the EOS-PM platform in December 2000. MODIS is a 36 channel radiometer covering 0·415-14·235 μm wavelengths, with spatial resolution from 250 m to 1 km at nadir. MODIS will be the primary EOS sensor for providing data on terrestrial biospheric dynamics and process activity. This paper presents the suite of global land products currently planned for EOSDIS implementation, to be developed by the authors of this paper, the MODIS land team (MODLAND). These include spectral albedo, land cover, spectral vegetation indices, snow and ice cover, surface temperature and fire, and a number of biophysical variables that will allow computation of global carbon cycles, hydrologic balances and biogeochemistry of critical greenhouse gases. Additionally, the regular global coverage of these variables will allow accurate surface change detection, a fundamental determinant of global change.
Airborne Instrument Simulator for the Lidar Surface Topography (LIST) Mission
NASA Technical Reports Server (NTRS)
Yu, Anthony W.; Krainak, Michael A.; Harding, David J.; Abshire, James B.; Sun, Xiaoli; Cavanaugh, John; Valett, Susan; Ramos-Izquierdo, Luis
2010-01-01
In 2007, the National Research Council (NRC) completed its first decadal survey for Earth science at the request of NASA, NOAA, and USGS. The Lidar Surface Topography (LIST) mission is one of fifteen missions recommended by NRC, whose primary objectives are to map global topography and vegetation structure at 5 m spatial resolution, and to acquire global coverage with a few years. NASA Goddard conducted an initial mission concept study for the LIST mission 2007, and developed the initial measurement requirements for the mission.
Next generation of global land cover characterization, mapping, and monitoring
Giri, Chandra; Pengra, Bruce; Long, J.; Loveland, Thomas R.
2013-01-01
Land cover change is increasingly affecting the biophysics, biogeochemistry, and biogeography of the Earth's surface and the atmosphere, with far-reaching consequences to human well-being. However, our scientific understanding of the distribution and dynamics of land cover and land cover change (LCLCC) is limited. Previous global land cover assessments performed using coarse spatial resolution (300 m–1 km) satellite data did not provide enough thematic detail or change information for global change studies and for resource management. High resolution (∼30 m) land cover characterization and monitoring is needed that permits detection of land change at the scale of most human activity and offers the increased flexibility of environmental model parameterization needed for global change studies. However, there are a number of challenges to overcome before producing such data sets including unavailability of consistent global coverage of satellite data, sheer volume of data, unavailability of timely and accurate training and validation data, difficulties in preparing image mosaics, and high performance computing requirements. Integration of remote sensing and information technology is needed for process automation and high-performance computing needs. Recent developments in these areas have created an opportunity for operational high resolution land cover mapping, and monitoring of the world. Here, we report and discuss these advancements and opportunities in producing the next generations of global land cover characterization, mapping, and monitoring at 30-m spatial resolution primarily in the context of United States, Group on Earth Observations Global 30 m land cover initiative (UGLC).
ERIC Educational Resources Information Center
Stidder, Gary; Haasner, Adrian
2007-01-01
Conflict resolution between different social groups is an issue that has continued to gain high profile news coverage both nationally and in a global context. In this respect, it has been shown that carefully designed and managed physical activity programmes can make a small but nonetheless invaluable contribution to reconciliation and…
Space technology and the optical sciences.
Yates, H W
1982-01-15
The earth-orbiting satellites and the deep-space probes have provided for the optical sciences platforms from which to study the earth, the solar system, and the universe with truly revolutionary capability. For the terrestrial sciences the orbiting platforms for optical measurements in both low and geostationary orbits have given us a view of our planet and a global coverage never before possible. For the astronomical applications of optical instruments that "cataract of the telescopic eye," the atmosphere of the earth has been left behind and through proximity, including actual contact, we now have resolution and spectral coverage limited only by money and motive.
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly Gridded TOA/Surface Fluxes and Clouds (SFC) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SFC is also produced for combinations of scanner instruments. All instantaneous shortwave, longwave, and window fluxes at the Top-of-the-Atmosphere (TOA) and surface from the CERES SSF product for a month are sorted by 1-degree spatial regions and by the local hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the SFC along with other flux statistics and scene information. These average fluxes are given for both clear-sky and total-sky scenes. The regional cloud properties are column averaged and are included on the SFC. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2003-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=100] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly Gridded TOA/Surface Fluxes and Clouds (SFC) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SFC is also produced for combinations of scanner instruments. All instantaneous shortwave, longwave, and window fluxes at the Top-of-the-Atmosphere (TOA) and surface from the CERES SSF product for a month are sorted by 1-degree spatial regions and by the local hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the SFC along with other flux statistics and scene information. These average fluxes are given for both clear-sky and total-sky scenes. The regional cloud properties are column averaged and are included on the SFC. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=100] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly Gridded TOA/Surface Fluxes and Clouds (SFC) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SFC is also produced for combinations of scanner instruments. All instantaneous shortwave, longwave, and window fluxes at the Top-of-the-Atmosphere (TOA) and surface from the CERES SSF product for a month are sorted by 1-degree spatial regions and by the local hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the SFC along with other flux statistics and scene information. These average fluxes are given for both clear-sky and total-sky scenes. The regional cloud properties are column averaged and are included on the SFC. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2003-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=100] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Monthly Gridded TOA/Surface Fluxes and Clouds (SFC) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SFC is also produced for combinations of scanner instruments. All instantaneous shortwave, longwave, and window fluxes at the Top-of-the-Atmosphere (TOA) and surface from the CERES SSF product for a month are sorted by 1-degree spatial regions and by the local hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the SFC along with other flux statistics and scene information. These average fluxes are given for both clear-sky and total-sky scenes. The regional cloud properties are column averaged and are included on the SFC. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=100] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
Combined Landsat-8 and Sentinel-2 Burned Area Mapping
NASA Astrophysics Data System (ADS)
Huang, H.; Roy, D. P.; Zhang, H.; Boschetti, L.; Yan, L.; Li, Z.
2017-12-01
Fire products derived from coarse spatial resolution satellite data have become an important source of information for the multiple user communities involved in fire science and applications. The advent of the MODIS on NASA's Terra and Aqua satellites enabled systematic production of 500m global burned area maps. There is, however, an unequivocal demand for systematically generated higher spatial resolution burned area products, in particular to examine the role of small-fires for various applications. Moderate spatial resolution contemporaneous satellite data from Landsat-8 and the Sentinel-2A and -2B sensors provide the opportunity for detailed spatial mapping of burned areas. Combined, these polar-orbiting systems provide 10m to 30m multi-spectral global coverage more than once every three days. This NASA funded research presents results to prototype a combined Landsat-8 Sentinel-2 burned area product. The Landsat-8 and Sentinel-2 pre-processing, the time-series burned area mapping algorithm, and preliminary results and validation using high spatial resolution commercial satellite data over Africa are presented.
Global-scale surface spectral variations on Titan seen from Cassini/VIMS
Barnes, J.W.; Brown, R.H.; Soderblom, L.; Buratti, B.J.; Sotin, Christophe; Rodriguez, S.; Le, Mouelic S.; Baines, K.H.; Clark, R.; Nicholson, P.
2007-01-01
We present global-scale maps of Titan from the Visual and Infrared Mapping Spectrometer (VIMS) instrument on Cassini. We map at 64 near-infrared wavelengths simultaneously, covering the atmospheric windows at 0.94, 1.08, 1.28, 1.6, 2.0, 2.8, and 5 ??m with a typical resolution of 50 km/pixel or a typical total integration time of 1 s. Our maps have five to ten times the resolution of ground-based maps, better spectral resolution across most windows, coverage in multiple atmospheric windows, and represent the first spatially resolved maps of Titan at 5 ??m. The VIMS maps provide context and surface spectral information in support of other Cassini instruments. We note a strong latitudinal dependence in the spectral character of Titan's surface, and partition the surface into 9 spectral units that we describe in terms of spectral and spatial characteristics. ?? 2006 Elsevier Inc. All rights reserved.
Regional to Global Biogenic Isoprene Emission Responses to Changes in Vegetation From 2000 to 2015
NASA Astrophysics Data System (ADS)
Chen, W. H.; Guenther, A. B.; Wang, X. M.; Chen, Y. H.; Gu, D. S.; Chang, M.; Zhou, S. Z.; Wu, L. L.; Zhang, Y. Q.
2018-04-01
Isoprene, a dominant biogenic volatile organic compound that is mainly emitted by trees, has a significant impact on the atmospheric chemistry. Regional to global changes in biogenic isoprene emission associated with vegetation variations between 2000 and 2015 were estimated using the MEGAN model with satellite land cover data for inputs in this study. The satellite data estimates of land cover changes were compared to results from previous investigators that have either conducted regional studies or have used lower resolution land cover data. The analysis indicates that tree coverage increases of >5% occurred in 13% of locations including in central China and Europe. In contrast, a decrease of >5% was observed in about 5% of locations, especially in tropical regions. The trends in global tree coverage from 2000 to 2015 resulted in a global isoprene emission decrease of only 1.5%, but there were significant regional variations. Obvious decreases in tree coverage in some tropical areas (e.g., Amazon Basin, Western Africa, Southeast Asia) resulted in a 10% reduction of regional isoprene emission due to agricultural expansion. Distinct increments of isoprene emission (5-10%) were mainly found in Northeast China and India and were associated with afforestation efforts. Deforestation and afforestation associated with managed plantations does not only affect the total forest coverage but also impacts average isoprene emission capacity, which can result in accelerated isoprene emission variations. Consequently, isoprene variation assessments are needed that not only account for changes in vegetation fractions but also consider the changes in plant species compositions of forests and other landscapes.
NASA Technical Reports Server (NTRS)
1987-01-01
The high-resolution imaging spectrometer (HIRIS) is an Earth Observing System (EOS) sensor developed for high spatial and spectral resolution. It can acquire more information in the 0.4 to 2.5 micrometer spectral region than any other sensor yet envisioned. Its capability for critical sampling at high spatial resolution makes it an ideal complement to the MODIS (moderate-resolution imaging spectrometer) and HMMR (high-resolution multifrequency microwave radiometer), lower resolution sensors designed for repetitive coverage. With HIRIS it is possible to observe transient processes in a multistage remote sensing strategy for Earth observations on a global scale. The objectives, science requirements, and current sensor design of the HIRIS are discussed along with the synergism of the sensor with other EOS instruments and data handling and processing requirements.
NASA Technical Reports Server (NTRS)
Stajner, I.; Wargan, K.; Pawson, S.; Hayashi, H.; Chang, L.-P.; Rood, R.
2004-01-01
We study the quality of lower stratospheric ozone fields from a three- dimensional global ozone assimilation system. Ozone in this region is important for the forcing of climate, but its global distribution is not fully known because of its large temporal and vertical variability. Modeled fields often have biases due to the inaccurate representation of transport processes in this region with strong gradients. Accurate ozonesonde or satellite occultation measurements have very limited coverage. Nadir measurements, such as those from the Solar Backscatter Ultraviolet/2 (SBUV/2) instrument that provide wide latitudinal coverage, lack the vertical resolution needed to represent sharp vertical features. Limb measurements, such as those from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS), provide a finer vertical resolution. We show that assimilation of MIPAS data in addition to SBUV/2 data leads to better estimates of ozone in comparison with independent high quality satellite, aircraft, and ozone sonde measurements. Other modifications to the statistical analysis that have an impact on the lower stratospheric ozone will be mentioned: error covariance modeling and data selection. Direct and indirect impacts of transport and chemistry models will be discussed. Implications for multi-year analyses and short-tern prediction will be addressed.
Global yellow fever vaccination coverage from 1970 to 2016: an adjusted retrospective analysis.
Shearer, Freya M; Moyes, Catherine L; Pigott, David M; Brady, Oliver J; Marinho, Fatima; Deshpande, Aniruddha; Longbottom, Joshua; Browne, Annie J; Kraemer, Moritz U G; O'Reilly, Kathleen M; Hombach, Joachim; Yactayo, Sergio; de Araújo, Valdelaine E M; da Nóbrega, Aglaêr A; Mosser, Jonathan F; Stanaway, Jeffrey D; Lim, Stephen S; Hay, Simon I; Golding, Nick; Reiner, Robert C
2017-11-01
Substantial outbreaks of yellow fever in Angola and Brazil in the past 2 years, combined with global shortages in vaccine stockpiles, highlight a pressing need to assess present control strategies. The aims of this study were to estimate global yellow fever vaccination coverage from 1970 through to 2016 at high spatial resolution and to calculate the number of individuals still requiring vaccination to reach population coverage thresholds for outbreak prevention. For this adjusted retrospective analysis, we compiled data from a range of sources (eg, WHO reports and health-service-provider registeries) reporting on yellow fever vaccination activities between May 1, 1939, and Oct 29, 2016. To account for uncertainty in how vaccine campaigns were targeted, we calculated three population coverage values to encompass alternative scenarios. We combined these data with demographic information and tracked vaccination coverage through time to estimate the proportion of the population who had ever received a yellow fever vaccine for each second level administrative division across countries at risk of yellow fever virus transmission from 1970 to 2016. Overall, substantial increases in vaccine coverage have occurred since 1970, but notable gaps still exist in contemporary coverage within yellow fever risk zones. We estimate that between 393·7 million and 472·9 million people still require vaccination in areas at risk of yellow fever virus transmission to achieve the 80% population coverage threshold recommended by WHO; this represents between 43% and 52% of the population within yellow fever risk zones, compared with between 66% and 76% of the population who would have required vaccination in 1970. Our results highlight important gaps in yellow fever vaccination coverage, can contribute to improved quantification of outbreak risk, and help to guide planning of future vaccination efforts and emergency stockpiling. The Rhodes Trust, Bill & Melinda Gates Foundation, the Wellcome Trust, the National Library of Medicine of the National Institutes of Health, the European Union's Horizon 2020 research and innovation programme. Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.
The Updating of Geospatial Base Data
NASA Astrophysics Data System (ADS)
Alrajhi, Muhamad N.; Konecny, Gottfried
2018-04-01
Topopographic mapping issues concern the area coverage at different scales and their age. The age of the map is determined by the system of updating. The United Nations (UNGGIM) have attempted to track the global map coverage at various scale ranges, which has greatly improved in recent decades. However the poor state of updating of base maps is still a global problem. In Saudi Arabia large scale mapping is carried out for all urban, suburban and rural areas by aerial surveys. Updating is carried out by remapping every 5 to 10 years. Due to the rapid urban development this is not satisfactory, but faster update methods are forseen by use of high resolution satellite imagery and the improvement of object oriented geodatabase structures, which will permit to utilize various survey technologies to update the photogrammetry established geodatabases. The longterm goal is to create an geodata infrastructure, which exists in Great Britain or Germany.
Global ice and land climate studies using scatterometer image data
NASA Astrophysics Data System (ADS)
Long, David G.; Drinkwater, Mark R.; Holt, Benjamin; Saatchi, Sasan; Bertoia, Cheryl
Scatterometers have provided continuous synoptic microwave radar coverage of the Earth from space for nearly a decade. NASA launched three scatterometers: the current SeaWinds scatterometer onboard QuikSCAT (QSCAT, 13.4 GHz) launched in 1999; the NASA scatterometer (NSCAT, 14.0 GHz), which flew on the Japanese Space Agency's ADEOS-1 platform during 1996-1997 and the Seasat-A scatterometer system (SASS, 14.6 GHz), which flew in 1978. The European Space Agency's (ESA) 5.3-GHz scatterometer (ESCAT) has been carried onboard both the ERS-1 and ERS-2 satellites since 1991.properties, including the phase state, of a particular surface type. Varying response from the surface also results from different polarizations, viewing angles and orientations, and radar frequencies. The wide swath of scatterometers provides near daily global coverage at intrinsic sensor resolutions that are generally between 25-50 km.
Double-Difference Global Adjoint Tomography
NASA Astrophysics Data System (ADS)
Orsvuran, R.; Bozdag, E.; Lei, W.; Tromp, J.
2017-12-01
The adjoint method allows us to incorporate full waveform simulations in inverse problems. Misfit functions play an important role in extracting the relevant information from seismic waveforms. In this study, our goal is to apply the Double-Difference (DD) methodology proposed by Yuan et al. (2016) to global adjoint tomography. Dense seismic networks, such as USArray, lead to higher-resolution seismic images underneath continents. However, the imbalanced distribution of stations and sources poses challenges in global ray coverage. We adapt double-difference multitaper measurements to global adjoint tomography. We normalize each DD measurement by its number of pairs, and if a measurement has no pair, as may frequently happen for data recorded at oceanic stations, classical multitaper measurements are used. As a result, the differential measurements and pair-wise weighting strategy help balance uneven global kernel coverage. Our initial experiments with minor- and major-arc surface waves show promising results, revealing more pronounced structure near dense networks while reducing the prominence of paths towards cluster of stations. We have started using this new measurement in global adjoint inversions, addressing azimuthal anisotropy in upper mantle. Meanwhile, we are working on combining the double-difference approach with instantaneous phase measurements to emphasize contributions of scattered waves in global inversions and extending it to body waves. We will present our results and discuss challenges and future directions in the context of global tomographic inversions.
Merging Ocean Color Data from Multiple Missions. Chapter 12
NASA Technical Reports Server (NTRS)
Gregg, Watson W.
2001-01-01
Oceanic phytoplankton may play an important role in the cycling of carbon on the Earth, through the uptake of carbon dioxide in the process of photosynthesis. Although they are ubiquitous in the global oceans, their abundances and dynamics are difficult to estimate, primarily due to the vast spatial extent of the oceans and the short time scales over which their abundances can change. Consequently, the effects of oceanic phytoplankton on biogeochemical cycling, climate change, and fisheries are not well known. In response to the potential importance of phytoplankton in the global carbon cycle and the lack of comprehensive data, the National Aeronautics and Space Administration (NASA) and the international community have established high priority satellite missions designed to acquire and produce high quality ocean color data. Seven of the missions are routine global observational missions: the Ocean Color and Temperature Sensor (OCTS), the Polarization and Directionality of the Earth's Reflectances sensor (POLDER), Sea-viewing Wide Field-of-view Sensor (SeaWiFS), Moderate Resolution Imaging Spectrometer-AM (MODIS-AM), Medium Resolution Imaging Spectrometer (MERIS), Global Imager (GLI), and MODIS-PM. In addition, there are several other missions capable of providing ocean color data on smaller scales. Most of these missions contain the spectral band complement considered necessary to derive oceanic pigment concentrations (i.e., phytoplankton abundance) and other related parameters. Many contain additional bands that can provide important ancillary information about the optical and biological state of the oceans. Any individual ocean color mission is limited in ocean coverage due to sun glint and clouds. For example, one of the first proposed missions, the SeaWiFS, can provide about 45% coverage of the global ocean in four days and only about 15% in one day.
NASA Technical Reports Server (NTRS)
Cook, William
1999-01-01
Measuring and understanding the distribution of ozone through the lower levels of Earth's atmosphere are high priorities in global change and climate research. Of particular interest now is the global distribution of ozone in the upper troposphere and lower stratosphere. Global coverage of the stratospheric ozone is feasible only via remote sensing instruments on a space-based platform. And though extensive monitoring tropospheric ozone is possible using instruments flown aboard conventional aircraft, a space-based system would be significantly less costly and provide information over a much broader area and produce more uniform coverage. Here we describe the prototype of an instrument being developed to monitor, from an orbiting spacecraft, the ozone found in Earth's upper troposphere and lower stratosphere. Our new spectrometer is an infrared Fabry-Perot interferometer which uses two synchrounously tuned etalons: a high resolution narrow band device and a lower resolution broader band filtering etalon. The prototype is a scanning device making use of nearly collimated input radiation and a single element detector. As presently configured, it is capable of providing a resolution better than 0.07/cm with a spectral band width approximately 5/cm wide and centered at 1054.7/cm. For the future space-based emission device a modification of the the prototype was to be made to employ innovative circle-to-line detector optics, those developed or in development at UM/SPRL, and a focal plane array detector. These enhancements would enable a simultaneous recording of the entire spectral range of interest, but with simple detection electronics and a significant gain in signal-to-noise over that of the scanning version.
Utazi, C Edson; Thorley, Julia; Alegana, Victor A; Ferrari, Matthew J; Takahashi, Saki; Metcalf, C Jessica E; Lessler, Justin; Tatem, Andrew J
2018-03-14
The expansion of childhood vaccination programs in low and middle income countries has been a substantial public health success story. Indicators of the performance of intervention programmes such as coverage levels and numbers covered are typically measured through national statistics or at the scale of large regions due to survey design, administrative convenience or operational limitations. These mask heterogeneities and 'coldspots' of low coverage that may allow diseases to persist, even if overall coverage is high. Hence, to decrease inequities and accelerate progress towards disease elimination goals, fine-scale variation in coverage should be better characterized. Using measles as an example, cluster-level Demographic and Health Surveys (DHS) data were used to map vaccination coverage at 1 km spatial resolution in Cambodia, Mozambique and Nigeria for varying age-group categories of children under five years, using Bayesian geostatistical techniques built on a suite of publicly available geospatial covariates and implemented via Markov Chain Monte Carlo (MCMC) methods. Measles vaccination coverage was found to be strongly predicted by just 4-5 covariates in geostatistical models, with remoteness consistently selected as a key variable. The output 1 × 1 km maps revealed significant heterogeneities within the three countries that were not captured using province-level summaries. Integration with population data showed that at the time of the surveys, few districts attained the 80% coverage, that is one component of the WHO Global Vaccine Action Plan 2020 targets. The elimination of vaccine-preventable diseases requires a strong evidence base to guide strategies and inform efficient use of limited resources. The approaches outlined here provide a route to moving beyond large area summaries of vaccination coverage that mask epidemiologically-important heterogeneities to detailed maps that capture subnational vulnerabilities. The output datasets are built on open data and methods, and in flexible format that can be aggregated to more operationally-relevant administrative unit levels. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.
SAR (Synthetic Aperture Radar). Earth observing system. Volume 2F: Instrument panel report
NASA Technical Reports Server (NTRS)
1987-01-01
The scientific and engineering requirements for the Earth Observing System (EOS) imaging radar are provided. The radar is based on Shuttle Imaging Radar-C (SIR-C), and would include three frequencies: 1.25 GHz, 5.3 GHz, and 9.6 GHz; selectable polarizations for both transmit and receive channels; and selectable incidence angles from 15 to 55 deg. There would be three main viewing modes: a local high-resolution mode with typically 25 m resolution and 50 km swath width; a regional mapping mode with 100 m resolution and up to 200 km swath width; and a global mapping mode with typically 500 m resolution and up to 700 km swath width. The last mode allows global coverage in three days. The EOS SAR will be the first orbital imaging radar to provide multifrequency, multipolarization, multiple incidence angle observations of the entire Earth. Combined with Canadian and Japanese satellites, continuous radar observation capability will be possible. Major applications in the areas of glaciology, hydrology, vegetation science, oceanography, geology, and data and information systems are described.
Preliminary Correlations of Gravity and Topography from Mars Global Surveyor
NASA Technical Reports Server (NTRS)
Zuber, M. T.; Tyler, G. L.; Smith, D. E.; Balmino, G. S.; Johnson, G. L.; Lemoine, F. G.; Neumann, G. A.; Phillips, R. J.; Sjogren, W. L.; Solomon, S. C.
1999-01-01
The Mars Global Surveyor (MGS) spacecraft is currently in a 400-km altitude polar mapping orbit and scheduled to begin global mapping of Mars in March of 1999. Doppler tracking data collected in this Gravity Calibration Orbit prior to the nominal mapping mission combined with observations from the MGS Science Phasing Orbit in Spring - Summer 1999 and the Viking and mariner 9 orbiters has led to preliminary high resolution gravity fields. Spherical harmonic expansions have been performed to degree and order 70 and are characterized by the first high spatial resolution coverage of high latitudes. Topographic mapping by the Mars Orbiter Laser Altimeter on MGS is providing measurements of the height of the martian surface with sub-meter vertical resolution and 5-30 m absolute accuracy. Data obtained during the circular mapping phase are expected to provide the first high resolution measurements of surface heights in the southern hemisphere. The combination of gravity and topography measurements provides information on the structure of the planetary interior, i.e. the rigidity and distribution of internal density. The observations can also be used to address the mechanisms of support of surface topography. Preliminary results of correlations of gravity and topography at long planetary wavelengths will be presented and the implications for internal structure will be addressed.
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Overview
,
2008-01-01
The National Aeronautics and Space Administration (NASA) launched Terra, the Earth Observing System's (EOS) flagship satellite platform on December 18, 1999. The polar-orbiting Terra contains five remote sensing instruments, which enable the scientific study and analyses of global terrestrial processes and manifestations of global change. One of the five instruments is the multispectral Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), which is built in Japan by a consortium of government, industry, and research groups. It has three spectral bands in the visible near-infrared region (VNIR), six bands in the shortwave infrared region (SWIR), and five bands in the thermal infrared region (TIR), with 15-, 30-, and 90-meter ground resolutions, respectively. This combination of wide spectral coverage and high spatial resolution allows ASTER to discriminate among a wide variety of surface materials. The VNIR subsystem also has a backward-viewing telescope for high-resolution (15-meter) stereoscopic observation in the along-track direction, which facilitates the generation of digital elevation models (DEM).
NASA Technical Reports Server (NTRS)
Reale, Oreste; Lau, William K.; Kim, Kyu-Myong; Brin, Eugenia
2009-01-01
This article investigates the role of the Saharan Air Layer (SAL) in tropical cyclogenetic processes associated with a non-developing and a developing African easterly wave observed during the Special Observation Period (SOP-3) phase of the 2006 NASA African Monsoon Multidisciplinary Analyses (NAMMA). The two waves are chosen because both interact heavily with Saharan air. A global data assimilation and forecast system, the NASA GEOS-5, is being run to produce a set of high-quality global analyses, inclusive of all observations used operationally but with denser satellite information. In particular, following previous works by the same Authors, the quality-controlled data from the Atmospheric Infrared Sounder (AIRS) used to produce these analyses have a better coverage than the one adopted by operational centers. From these improved analyses, two sets of 31 5-day high resolution forecasts, at horizontal resolutions of both half and quarter degrees, are produced. Results show that very steep moisture gradients are associated with the SAL in forecasts and analyses even at great distance from the Sahara. In addition, a thermal dipole (warm above, cool below) is present in the non-developing case. Moderate Resolution Imaging Spectroradiometer (MODIS) show that aerosol optical thickness is higher in the non-developing case. Altogether, results suggest that radiative effect of dust may play some role in producing a thermal structure less favorable to cyclogenesis. Results also indicate that only global horizontal resolutions on the order of 20-30 kilometers can capture the large-scale transport and the fine thermal structure of the SAL, inclusive of the sharp moisture gradients, reproducing the effect of tropical cyclone suppression which has been hypothesized by previous authors from observational and regional modeling perspectives. These effects cannot be fully represented at lower resolutions. Global resolution of a quarter of a degree is a minimum critical threshold to investigate Atlantic tropical cyclogenesis from a global modeling perspective.
The Use of the Regional Navy Coastal Ocean Model (RNCOM) by the US Navy in Operational Oceanography
NASA Astrophysics Data System (ADS)
Rayburn, J. T.
2016-02-01
The operational RNCOM is a 1/30° resolution nested model run daily by the Naval Oceanographic Office (NAVOCEANO), Stennis Space Center, Mississippi. Operational RNCOM areas are used in combination with the Global HYbrid Coordinate Ocean Model (HYCOM) to provide full global model coverage with enhanced resolution for temperature, salinity, currents in key areas. This talk will discuss two aspects of RNCOM. First, it will focus on how the model is configured. As a nested model, issues to consider include the source of boundary condition, boundary placement, and observational inputs. Secondly, this talk will focus on the strengths and weaknesses RNCOM demonstrates in accurately characterizing ocean condition with respect to HYCOM and how this regional model's output is used by NAVOCEANO Ocean Forecasters to develop operational forecasts.
NASA Technical Reports Server (NTRS)
Li, Xuanli; Lang, Timothy J.; Mecikalski, John; Castillo, Tyler; Hoover, Kacie; Chronis, Themis
2017-01-01
Cyclone Global Navigation Satellite System (CYGNSS): a constellation of 8 micro-satellite observatories launched in November 2016, to measure near-surface oceanic wind speed. Main goal: To monitor surface wind fields of the Tropical Cyclones' inner core, including regions beneath the intense eye wall and rain bands that could not previously be measured from space; Cover 38 deg S -38 deg N with unprecedented temporal resolution and spatial coverage, under all precipitating conditions Low flying satellite: Pass over ocean surface more frequently than one large satellite. A median(mean) revisit time of 2.8(7.2) hrs.
Estimating stratospheric temperature trends using satellite microwave radiances
NASA Technical Reports Server (NTRS)
Hudson, Robert D.; Newman, Paul A.; Schoeberl, Mark R.
1990-01-01
The objective was to evaluate and intercompare stratospheric temperatures using Microwave Sounding Unit (MSU) data as a basis data set. The MSU, aboard the NOAA polar orbiter satellite series, provides twice daily global coverage over a layer (50-150 mb) at approximately a (170km)(exp 2) resolution. Conventional data sets will be compared to the satellite data in the lower stratosphere in order to assess their quality for trend computations.
Comparing Goldstone Solar System Radar Earth-based Observations of Mars with Orbital Datasets
NASA Technical Reports Server (NTRS)
Haldemann, A. F. C.; Larsen, K. W.; Jurgens, R. F.; Slade, M. A.
2005-01-01
The Goldstone Solar System Radar (GSSR) has collected a self-consistent set of delay-Doppler near-nadir radar echo data from Mars since 1988. Prior to the Mars Global Surveyor (MGS) Mars Orbiter Laser Altimeter (MOLA) global topography for Mars, these radar data provided local elevation information, along with radar scattering information with global coverage. Two kinds of GSSR Mars delay-Doppler data exist: low 5 km x 150 km resolution and, more recently, high (5 to 10 km) spatial resolution. Radar data, and non-imaging delay-Doppler data in particular, requires significant data processing to extract elevation, reflectivity and roughness of the reflecting surface. Interpretation of these parameters, while limited by the complexities of electromagnetic scattering, provide information directly relevant to geophysical and geomorphic analyses of Mars. In this presentation we want to demonstrate how to compare GSSR delay-Doppler data to other Mars datasets, including some idiosyncracies of the radar data. Additional information is included in the original extended abstract.
The Soil Moisture Active and Passive Mission (SMAP): Science and Applications
NASA Technical Reports Server (NTRS)
Entekhabi, Dara; O'Neill, Peggy; Njoku, Eni
2009-01-01
The Soil Moisture Active and Passive mission (SMAP) will provide global maps of soil moisture content and surface freeze/thaw state. Global measurements of these variables are critical for terrestrial water and carbon cycle applications. The SMAP observatory consists of two multipolarization L-band sensors, a radar and radiometer, that share a deployable-mesh reflector antenna. The combined observations from the two sensors will allow accurate estimation of soil moisture at hydrometeorological (10 km) and hydroclimatological (40 km) spatial scales. The rotating antenna configuration provides conical scans of the Earth surface at a constant look angle. The wide-swath (1000 km) measurements will allow global mapping of soil moisture and its freeze/thaw state with 2-3 days revisit. Freeze/thaw in boreal latitudes will be mapped using the radar at 3 km resolution with 1-2 days revisit. The synergy of active and passive observations enables measurements of soil moisture and freeze/thaw state with unprecedented resolution, sensitivity, area coverage and revisit.
Global cancer control: responding to the growing burden, rising costs and inequalities in access
Braga, Sofia; Bystricky, Branislav; Qvortrup, Camilla; Criscitiello, Carmen; Esin, Ece; Sonke, Gabe S; Martínez, Guillem Argilés; Frenel, Jean-Sebastian; Karamouzis, Michalis; Strijbos, Michiel; Yazici, Ozan; Bossi, Paolo; Banerjee, Susana; Troiani, Teresa; Eniu, Alexandru; Ciardiello, Fortunato; Tabernero, Josep; Zielinski, Christoph C; Casali, Paolo G; Cardoso, Fatima; Douillard, Jean-Yves; McGregor, Keith; Bricalli, Gracemarie; Vyas, Malvika; Ilbawi, André
2018-01-01
The cancer burden is rising globally, exerting significant strain on populations and health systems at all income levels. In May 2017, world governments made a commitment to further invest in cancer control as a public health priority, passing the World Health Assembly Resolution 70.12 on cancer prevention and control within an integrated approach. In this manuscript, the 2016 European Society for Medical Oncology Leadership Generation Programme participants propose a strategic framework that is in line with the 2017 WHO Cancer Resolution and consistent with the principle of universal health coverage, which ensures access to optimal cancer care for all people because health is a basic human right. The time for action is now to reduce barriers and provide the highest possible quality cancer care to everyone regardless of circumstance, precondition or geographic location. The national actions and the policy recommendations in this paper set forth the vision of its authors for the future of global cancer control at the national level, where the WHO Cancer Resolution must be implemented if we are to reduce the cancer burden, avoid unnecessary suffering and save as many lives as possible. PMID:29464109
A search for life on earth at 100 meter resolution
NASA Technical Reports Server (NTRS)
Sagan, C.; Wallace, D.
1970-01-01
A study of several thousand photos indicated approximately 1% of Gemini and Apollo photographs of the earth at 100 m resolution revealed signs of life; rectangular arrays due to human agricultural and urban territoriality, roads, canals, jet contrails, and industrial pollution. Potential false positives such as dunes, sand bars, and jet stream clouds abound. A curve was derived for the detectivity of contemporary life on earth, in a plot of ground resolution versus global coverage. A comparable biology on Mars would not have been detected by all observations of Mars through Mariner 7. Forthcoming Mars orbiter and lander imaging experiments hold significant promise of detecting life on Mars of contemporary terrestrial extent and advancement, should such life exist.
Wang, Tianxing; Shi, Jiancheng; Jing, Yingying; Zhao, Tianjie; Ji, Dabin; Xiong, Chuan
2014-01-01
Global warming induced by atmospheric CO2 has attracted increasing attention of researchers all over the world. Although space-based technology provides the ability to map atmospheric CO2 globally, the number of valid CO2 measurements is generally limited for certain instruments owing to the presence of clouds, which in turn constrain the studies of global CO2 sources and sinks. Thus, it is a potentially promising work to combine the currently available CO2 measurements. In this study, a strategy for fusing SCIAMACHY and GOSAT CO2 measurements is proposed by fully considering the CO2 global bias, averaging kernel, and spatiotemporal variations as well as the CO2 retrieval errors. Based on this method, a global CO2 map with certain UTC time can also be generated by employing the pattern of the CO2 daily cycle reflected by Carbon Tracker (CT) data. The results reveal that relative to GOSAT, the global spatial coverage of the combined CO2 map increased by 41.3% and 47.7% on a daily and monthly scale, respectively, and even higher when compared with that relative to SCIAMACHY. The findings in this paper prove the effectiveness of the combination method in supporting the generation of global full-coverage XCO2 maps with higher temporal and spatial sampling by jointly using these two space-based XCO2 datasets. PMID:25119468
GLOBATO: An enhanced global relief model at 30 arc-seconds resolution
NASA Astrophysics Data System (ADS)
O'Leary, V.; Amante, C.
2017-12-01
The National Centers for Environmental Information (NCEI), an office of the National Oceanic and Atmospheric Administration (NOAA), first developed a digital bathymetric and elevation model, ETOPO5, from publicly available data in 1993. For nearly 25 years, NCEI's ETOPO family of global relief models have supported research at a planetary scale, including tsunami forecasting, ocean circulation modeling, visualization of the seafloor, understanding geological phenomena, and aiding the development of other global and regional elevation models. GLOBATO (GLObal BAThymetry and TOpography) is now the most detailed version released by NCEI with a horizontal resolution of 30 arc-seconds and succeeds ETOPO1 with the inclusion of several new or updated data-sets for the seafloor as well as land areas. GLOBATO is a compilation of data derived from models of satellite measurements, ship depth soundings, and multibeam surveys, as well as regional models developed for Greenland and Antarctica. These data were converted from different formats, resolutions, spatial distributions, and projections into a single global model using GDAL v2.2 and MB-System v5.5. As with previous NCEI models, GLOBATO is available in two formats, "bedrock elevation" (measured as the base of major ice sheets) and "ice surface elevation" (measured as the surface of major ice sheets) which provides comprehensive topographic and bathymetric coverage between +- 90 degrees latitude and +- 180 degrees longitude. Adhering to best practices, GLOBATO, all related digital products, and any supporting documentation are available online through the NCEI data portal. These new, high resolution models will better support the variety of research ETOPO1 has made possible.
NASA Technical Reports Server (NTRS)
Knowlton, Kelly; Andrews, Jane C.; Ryan, Robert E.
2007-01-01
Atmospheric aerosols are a major contributor to diffuse irradiance. This Candidate Solution suggests using the OMI (Ozone Monitoring Instrument) aerosol product as input into a radiative transfer model, which would calculate the ratio of diffuse to global irradiance at the Earth s surface. This ratio can significantly influence the rate of photosynthesis in plants; increasing the ratio of diffuse to global irradiance can accelerate photosynthesis, resulting in greater plant productivity. Accurate values of this ratio could be useful in predicting crop productivity, thereby improving forecasts of regional food resources. However, disagreements exist between diffuse-to-global irradiance values measured by different satellites and ground sensors. OMI, with its unique combination of spectral bands, high resolution, and daily global coverage, may be able to provide more accurate aerosol measurements than other comparable sensors.
Shoberg, Thomas G.; Stoddard, Paul R.
2013-01-01
The ability to augment local gravity surveys with additional gravity stations from easily accessible national databases can greatly increase the areal coverage and spatial resolution of a survey. It is, however, necessary to integrate such data seamlessly with the local survey. One challenge to overcome in integrating data from national databases is that these data are typically of unknown quality. This study presents a procedure for the evaluation and seamless integration of gravity data of unknown quality from a national database with data from a local Global Positioning System (GPS)-based survey. The starting components include the latitude, longitude, elevation and observed gravity at each station location. Interpolated surfaces of the complete Bouguer anomaly are used as a means of quality control and comparison. The result is an integrated dataset of varying quality with many stations having GPS accuracy and other reliable stations of unknown origin, yielding a wider coverage and greater spatial resolution than either survey alone.
Mentoring Temporal and Spatial Variations in Rainfall across Wadi Ar-Rumah, Saudi Arabia
NASA Astrophysics Data System (ADS)
Alharbi, T.; Ahmed, M.
2015-12-01
Across the Kingdom of Saudi Arabia (KSA), the fresh water resources are limited only to those found in aquifer systems. Those aquifers were believed to be recharged during the previous wet climatic period but still receiving modest local recharge in interleaving dry periods such as those prevailing at present. Quantifying temporal and spatial variabilities in rainfall patterns, magnitudes, durations, and frequencies is of prime importance when it comes to sustainable management of such aquifer systems. In this study, an integrated approach, using remote sensing and field data, was used to assess the past, the current, and the projected spatial and temporal variations in rainfall over one of the major watersheds in KSA, Wadi Ar-Rumah. This watershed was selected given its larger areal extent and population intensity. Rainfall data were extracted from (1) the Climate Prediction Centers (CPC) Merged Analysis of Precipitation (CMAP; spatial coverage: global; spatial resolution: 2.5° × 2.5°; temporal coverage: January 1979 to April 2015; temporal resolution: monthly), and (2) the Tropical Rainfall Measuring Mission (TRMM; spatial coverage: 50°N to 50°S; spatial resolution: 0.25° × 0.25°; temporal coverage: January 1998 to March 2015; temporal resolution: 3 hours) and calibrated against rainfall measurements extracted from rain gauges. Trends in rainfall patterns were examined over four main investigation periods: period I (01/1979 to 12/1985), period II (01/1986 to 12/1992), period III (01/1993 to 12/2002), and period IV (01/2003 to 12/2014). Our findings indicate: (1) a significant increase (+14.19 mm/yr) in rainfall rates were observed during period I, (2) a significant decrease in rainfall rates were observed during periods II (-5.80 mm/yr), III (-9.38 mm/yr), and IV (-2.46 mm/yr), and (3) the observed variations in rainfall rates are largely related to the temporal variations in the northerlies (also called northwesterlies) and the monsoonal wind regimes.
CERES Monthly Gridded Single Satellite Fluxes and Clouds (FSW) in HDF (CER_FSW_TRMM-PFM-VIRS_Beta1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator); Barkstrom, Bruce R. (Principal Investigator)
The Monthly Gridded Radiative Fluxes and Clouds (FSW) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The FSW is also produced for combinations of scanner instruments. All instantaneous fluxes from the CERES CRS product for a month are sorted by 1-degree spatial regions and by the Universal Time (UT) hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the FSW along with other flux statistics and scene information. The mean adjusted fluxes at the four atmospheric levels defined by CRS are also included for both clear-sky and total-sky scenes. In addition, four cloud height categories are defined by dividing the atmosphere into four intervals with boundaries at the surface, 700-, 500-, 300-hPa, and the Top-of-the-Atmosphere (TOA). The cloud layers from CRS are put into one of the cloud height categories and averaged over the region. The cloud properties are also column averaged and included on the FSW. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator); Barkstrom, Bruce R. (Principal Investigator)
The Monthly Gridded Radiative Fluxes and Clouds (FSW) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The FSW is also produced for combinations of scanner instruments. All instantaneous fluxes from the CERES CRS product for a month are sorted by 1-degree spatial regions and by the Universal Time (UT) hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the FSW along with other flux statistics and scene information. The mean adjusted fluxes at the four atmospheric levels defined by CRS are also included for both clear-sky and total-sky scenes. In addition, four cloud height categories are defined by dividing the atmosphere into four intervals with boundaries at the surface, 700-, 500-, 300-hPa, and the Top-of-the-Atmosphere (TOA). The cloud layers from CRS are put into one of the cloud height categories and averaged over the region. The cloud properties are also column averaged and included on the FSW. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator); Barkstrom, Bruce R. (Principal Investigator)
The Monthly Gridded Radiative Fluxes and Clouds (FSW) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The FSW is also produced for combinations of scanner instruments. All instantaneous fluxes from the CERES CRS product for a month are sorted by 1-degree spatial regions and by the Universal Time (UT) hour of observation. The mean of the instantaneous fluxes for a given region-hour bin is determined and recorded on the FSW along with other flux statistics and scene information. The mean adjusted fluxes at the four atmospheric levels defined by CRS are also included for both clear-sky and total-sky scenes. In addition, four cloud height categories are defined by dividing the atmosphere into four intervals with boundaries at the surface, 700-, 500-, 300-hPa, and the Top-of-the-Atmosphere (TOA). The cloud layers from CRS are put into one of the cloud height categories and averaged over the region. The cloud properties are also column averaged and included on the FSW. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2001-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1 degree; Longitude_Resolution=1 degree; Horizontal_Resolution_Range=100 km - < 250 km or approximately 1 degree - < 2.5 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
Validation of "AW3D" Global Dsm Generated from Alos Prism
NASA Astrophysics Data System (ADS)
Takaku, Junichi; Tadono, Takeo; Tsutsui, Ken; Ichikawa, Mayumi
2016-06-01
Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM), one of onboard sensors carried by Advanced Land Observing Satellite (ALOS), was designed to generate worldwide topographic data with its optical stereoscopic observation. It has an exclusive ability to perform a triplet stereo observation which views forward, nadir, and backward along the satellite track in 2.5 m ground resolution, and collected its derived images all over the world during the mission life of the satellite from 2006 through 2011. A new project, which generates global elevation datasets with the image archives, was started in 2014. The data is processed in unprecedented 5 m grid spacing utilizing the original triplet stereo images in 2.5 m resolution. As the number of processed data is growing steadily so that the global land areas are almost covered, a trend of global data qualities became apparent. This paper reports on up-to-date results of the validations for the accuracy of data products as well as the status of data coverage in global areas. The accuracies and error characteristics of datasets are analyzed by the comparison with existing global datasets such as Ice, Cloud, and land Elevation Satellite (ICESat) data, as well as ground control points (GCPs) and the reference Digital Elevation Model (DEM) derived from the airborne Light Detection and Ranging (LiDAR).
NASA Technical Reports Server (NTRS)
Clancy, R. Todd; Rusch, David W.
1989-01-01
Atmospheric temperature profiles for the altitude range 58-90 km were calculated using data on global UV limb radiances from the SME satellite. The major elements of this climatology include a high vertical resolution (about 4 km) and the coverage of the 70-90 km altitude region. The analysis of this extensive data set provides a global definition of mesospheric-lower thermospheric temperature trends over the 1982-1986 period. The observations suggest a pattern of 1-2 K/year decreases in temperatures at 80-90-km altitudes accompanied by 0.5-1.5 K/year increases in temperatures at 65-80-km altitudes.
Mars Operational Environmental Satellite (MOES): A post-Mars Observer discovery mission
NASA Technical Reports Server (NTRS)
Limaye, Sanjay S.
1993-01-01
Mars Operational Environmental Satellite (MOES) is a Discovery concept mission that is designed to observe the global short-term weather phenomena on Mars in a systematic fashion. Even after the Mariner, Viking, and, soon, Mars Observer missions, crucial aspects of the martian atmosphere will remain unobserved systematically. Achieving a better understanding of the cycles of dust, water vapor, and ices on Mars requires detailed information about atmospheric transports of those quantities associated with the weather systems, particularly those arising in mid latitudes during fall and winter. It also requires a quantitive understanding of the processes responsible for the onset and evolution of dust storms on all scales. Whereas on Earth the system of geosynchronous and polar orbiting satellites provides continuous coverage of the weather systems, on Mars the time history of important events such as regional and global dust storms remains unobserved. To understand the transport of tracers in the martian atmosphere and particularly to identify their sources and sinks, it is necessary to have systematic global, synoptic observations that have yet to be attained. Clearly these requirements are not easy to achieve from a single spacecraft in orbit, but if we focus on specific regions of the planet, e.g., polar vs. low and mid latitudes, then it is possible to attain a nearly ideal coverage at a reasonable spatial and temporal resolution with a system of just two satellites. Mars Observer is about to yield good coverage of the polar latitudes, so we focus initially on the region not covered well in terms of diurnal coverage, and in terms of desired observations will provide the initial data for the numerical models of the martian weather and climate that can be verified only with better temporal and spatial data.
NASA Astrophysics Data System (ADS)
Hardin, Perry J.; Long, David G.
1993-08-01
There is considerable interest in utilizing microwave and visible spectrum imagery for the assessment of tropical rain forests. Because rain forest spans large sub-continental areas, medium resolution (1 - 16 km) imagery will play an important role in providing a global perspective of any forest removal or change. Since 1978, AVHRR imagery from NOAA polar orbiters has provided coverage of tropical regions at this desirable resolution, but much of the imagery is plagued with heavy cloud cover typical of equatorial regions. In contrast, no historical source of active microwave imagery at native 1 - 16 km resolution exists for all the global rain forest regions. In this paper, the authors compare the utility of Seasat scatterometer (SASS) ku-band microwave data to early-date AVHRR vegetation index products for discrimination of tropical vegetation formations. When considered separately, both the AVHRR imagery and the SASS imagery could be used to distinguish between broad categories of equatorial land cover, but the AVHRR imagery was slightly superior. When combined, the two data sets provided discrimination capability superior than could be obtained by using either set alone.
Evolution of Satellite Imagers and Sounders for Low Earth Orbit and Technology Directions at NASA
NASA Technical Reports Server (NTRS)
Pagano, Thomas S.; McClain, Charles R.
2010-01-01
Imagers and Sounders for Low Earth Orbit (LEO) provide fundamental global daily observations of the Earth System for scientists, researchers, and operational weather agencies. The imager provides the nominal 1-2 km spatial resolution images with global coverage in multiple spectral bands for a wide range of uses including ocean color, vegetation indices, aerosol, snow and cloud properties, and sea surface temperature. The sounder provides vertical profiles of atmospheric temperature, water vapor cloud properties, and trace gases including ozone, carbon monoxide, methane and carbon dioxide. Performance capabilities of these systems has evolved with the optical and sensing technologies of the decade. Individual detectors were incorporated on some of the first imagers and sounders that evolved to linear array technology in the '80's. Signal-to-noise constraints limited these systems to either broad spectral resolution as in the case of the imager, or low spatial resolution as in the case of the sounder. Today's area 2-dimensional large format array technology enables high spatial and high spectral resolution to be incorporated into a single instrument. This places new constraints on the design of these systems and enables new capabilities for scientists to examine the complex processes governing the Earth System.
BrO, OClO and HCHO Observations from the EOS-Aura Ozone Monitoring Instrument
NASA Astrophysics Data System (ADS)
Kurosu, T. P.; Chance, K.; Sioris, C. E.
2004-12-01
The Ozone Monitoring Instrument (OMI) was launched on 15 July 2004 on the EOS-Aura platform into a sun-synchronous, polar orbit with an equator crossing time of 13:45h (ascending node). OMI is a nadir-viewing near-UV/Visible spectrometer, covering the spectral region of 270 nm to 500 nm with a resolution between 0.45 nm and 1.0 nm and a nominal ground footprint of 13 km×24 km. Global coverage is achieved in one day. The very high spatial resolution of OMI measurements sets a new standard for trace gas and air quality monitoring from space. Combined with daily global coverage, this significantly advances our ability to answer outstanding questions on air pollution, including the determination of BrO sources in mid and low latitudes, BrO--O3 anti-correlations as a function of latitude, and the production of formaldehyde in cities of the developing world. We introduce the design of the OMI operational retrieval algorithm for BrO, OClO and HCHO. Based on a direct (non-DOAS) non-linear fitting approach, it includes wavelength calibration for radiances and irradiances, an undersampling correction, and the characterization of the instrument slit function. We will present results of BrO (global distribution, and tropospheric contributions from the break-up ice shelves and volcanic emissions), formaldehyde (over regions of isoprene emissions, forest fires, and heavy urban pollution), and, contingent upon the availability of suitable OMI observations, OClO (under ozone hole conditions). Where available, trace gas retrievals from OMI will be compared to results from the SCIAMACHY and GOME instruments.
Monitoring interannual variation in global crop yield using long-term AVHRR and MODIS observations
NASA Astrophysics Data System (ADS)
Zhang, Xiaoyang; Zhang, Qingyuan
2016-04-01
Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) data have been extensively applied for crop yield prediction because of their daily temporal resolution and a global coverage. This study investigated global crop yield using daily two band Enhanced Vegetation Index (EVI2) derived from AVHRR (1981-1999) and MODIS (2000-2013) observations at a spatial resolution of 0.05° (∼5 km). Specifically, EVI2 temporal trajectory of crop growth was simulated using a hybrid piecewise logistic model (HPLM) for individual pixels, which was used to detect crop phenological metrics. The derived crop phenology was then applied to calculate crop greenness defined as EVI2 amplitude and EVI2 integration during annual crop growing seasons, which was further aggregated for croplands in each country, respectively. The interannual variations in EVI2 amplitude and EVI2 integration were combined to correlate to the variation in cereal yield from 1982-2012 for individual countries using a stepwise regression model, respectively. The results show that the confidence level of the established regression models was higher than 90% (P value < 0.1) in most countries in the northern hemisphere although it was relatively poor in the southern hemisphere (mainly in Africa). The error in the yield predication was relatively smaller in America, Europe and East Asia than that in Africa. In the 10 countries with largest cereal production across the world, the prediction error was less than 9% during past three decades. This suggests that crop phenology-controlled greenness from coarse resolution satellite data has the capability of predicting national crop yield across the world, which could provide timely and reliable crop information for global agricultural trade and policymakers.
NASA Technical Reports Server (NTRS)
Hammerling, Dorit M.; Michalak, Anna M.; Kawa, S. Randolph
2012-01-01
Satellite observations of CO2 offer new opportunities to improve our understanding of the global carbon cycle. Using such observations to infer global maps of atmospheric CO2 and their associated uncertainties can provide key information about the distribution and dynamic behavior of CO2, through comparison to atmospheric CO2 distributions predicted from biospheric, oceanic, or fossil fuel flux emissions estimates coupled with atmospheric transport models. Ideally, these maps should be at temporal resolutions that are short enough to represent and capture the synoptic dynamics of atmospheric CO2. This study presents a geostatistical method that accomplishes this goal. The method can extract information about the spatial covariance structure of the CO2 field from the available CO2 retrievals, yields full coverage (Level 3) maps at high spatial resolutions, and provides estimates of the uncertainties associated with these maps. The method does not require information about CO2 fluxes or atmospheric transport, such that the Level 3 maps are informed entirely by available retrievals. The approach is assessed by investigating its performance using synthetic OCO-2 data generated from the PCTM/ GEOS-4/CASA-GFED model, for time periods ranging from 1 to 16 days and a target spatial resolution of 1deg latitude x 1.25deg longitude. Results show that global CO2 fields from OCO-2 observations can be predicted well at surprisingly high temporal resolutions. Even one-day Level 3 maps reproduce the large-scale features of the atmospheric CO2 distribution, and yield realistic uncertainty bounds. Temporal resolutions of two to four days result in the best performance for a wide range of investigated scenarios, providing maps at an order of magnitude higher temporal resolution relative to the monthly or seasonal Level 3 maps typically reported in the literature.
Azimuthally Anisotropic Global Adjoint Tomography
NASA Astrophysics Data System (ADS)
Bozdag, E.; Orsvuran, R.; Lefebvre, M. P.; Lei, W.; Peter, D. B.; Ruan, Y.; Smith, J. A.; Komatitsch, D.; Tromp, J.
2017-12-01
Earth's upper mantle shows significant evidence of anisotropy as a result of its composition and deformation. After the first-generation global adjoint tomography model, GLAD-M15 (Bozdag et al. 2016), which has transverse isotropy confined to upper mantle, we continue our iterations including surface-wave azimuthal anisotropy with an emphasis on the upper mantle. We are focusing on four elastic parameters that surface waves are known to be most sensitive to, namely, vertically and horizontally polarized shear waves and the density-normalised anisotropic parameters Gc' & Gs'. As part of the current anisotropic inversions, which will lead to our "second-generation" global adjoint tomography model, we have started exploring new misfits based on a double-difference approach (Yuan et al. 2016). We define our misfit function in terms of double-difference multitaper measurements, where each waveform is normalized by its number of pairs in the period ranges 45-100 s & 90-250 s. New measurements result in better balanced gradients while extracting more information underneath clusters of stations, such as USArray. Our initial results reveals multi-scale anisotorpic signals depending on ray (kernel) coverage close to continental-scale resolution in areas with dense coverage, consistent with previous studies.
Superposed epoch analysis of ion temperatures during CME- and CIR/HSS-driven storms
NASA Astrophysics Data System (ADS)
Keesee, A. M.; Scime, E. E.
2012-12-01
The NASA Two Wide-angle Imaging Neutral atom Spectrometers (TWINS) Mission provides a global view of the magnetosphere with near-continuous coverage. Utilizing a novel technique to calculate ion temperatures from the TWINS energetic neutral atom (ENA) measurements, we generate ion temperature maps of the magnetosphere. These maps can be used to study ion temperature evolution during geomagnetic storms. A superposed epoch analysis of the ion temperature evolution during 48 storms will be presented. Zaniewski et al. [2006] performed a superposed epoch analysis of ion temperatures by storm interval using data from the MENA instrument on the IMAGE mission, demonstrating significant dayside ion heating during the main phase. The TWINS measurements provide more continuous coverage and improved spatial and temporal resolution. Denton and Borovsky [2008] noted differences in ion temperature evolution at geosynchronous orbit between coronal mass ejection (CME)- and corotating interaction region (CIR)/high speed stream (HSS)- driven storms. Using our global ion temperature maps, we have found consistent results for select individual storms [Keesee et al., 2012]. We will present superposed epoch analyses for the subgroups of CME- and CIR/HSS-driven storms to compare global ion temperature evolution during the two types of storms.
Williams, David A.; Keszthelyi, Laszlo P.; Crown, David A.; Yff, Jessica A.; Jaeger, Windy L.; Schenk, Paul M.; Geissler, Paul E.; Becker, Tammy L.
2011-01-01
Io, discovered by Galileo Galilei on January 7–13, 1610, is the innermost of the four Galilean satellites of the planet Jupiter (Galilei, 1610). It is the most volcanically active object in the Solar System, as recognized by observations from six National Aeronautics and Space Administration (NASA) spacecraft: Voyager 1 (March 1979), Voyager 2 (July 1979), Hubble Space Telescope (1990–present), Galileo (1996–2001), Cassini (December 2000), and New Horizons (February 2007). The lack of impact craters on Io in any spacecraft images at any resolution attests to the high resurfacing rate (1 cm/yr) and the dominant role of active volcanism in shaping its surface. High-temperature hot spots detected by the Galileo Solid-State Imager (SSI), Near-Infrared Mapping Spectrometer (NIMS), and Photopolarimeter-Radiometer (PPR) usually correlate with darkest materials on the surface, suggesting active volcanism. The Voyager flybys obtained complete coverage of Io's subjovian hemisphere at 500 m/pixel to 2 km/pixel, and most of the rest of the satellite at 5–20 km/pixel. Repeated Galileo flybys obtained complementary coverage of Io's antijovian hemisphere at 5 m/pixel to 1.4 km/pixel. Thus, the Voyager and Galileo data sets were merged to enable the characterization of the whole surface of the satellite at a consistent resolution. The United States Geological Survey (USGS) produced a set of four global mosaics of Io in visible wavelengths at a spatial resolution of 1 km/pixel, released in February 2006, which we have used as base maps for this new global geologic map. Much has been learned about Io's volcanism, tectonics, degradation, and interior since the Voyager flybys, primarily during and following the Galileo Mission at Jupiter (December 1995–September 2003), and the results have been summarized in books published after the end of the Galileo Mission. Our mapping incorporates this new understanding to assist in map unit definition and to provide a global synthesis of Io's geology.
Monitoring Precipitation from Space: targeting Hydrology Community?
NASA Astrophysics Data System (ADS)
Hong, Y.; Turk, J.
2005-12-01
During the past decades, advances in space, sensor and computer technology have made it possible to estimate precipitation nearly globally from a variety of observations in a relatively direct manner. The success of Tropical Precipitation Measuring Mission (TRMM) has been a significant advance for modern precipitation estimation algorithms to move toward daily quarter degree measurements, while the need for precipitation data at temporal-spatial resolutions compatible with hydrologic modeling has been emphasized by the end user: hydrology community. Can the future deployment of Global Precipitation Measurement constellation of low-altitude orbiting satellites (covering 90% of the global with a sampling interval of less than 3-hours), in conjunction with the existing suite of geostationary satellites, results in significant improvements in scale and accuracy of precipitation estimates suitable for hydrology applications? This presentation will review the current state of satellite-derived precipitation estimation and demonstrate the early results and primary barriers to full global high-resolution precipitation coverage. An attempt to facilitate the communication between data producers and users will be discussed by developing an 'end-to-end' uncertainty propagation analysis framework to quantify both the precipitation estimation error structure and the error influence on hydrological modeling.
Comparison of C-band and Ku-band scatterometry for medium-resolution tropical forest inventory
NASA Astrophysics Data System (ADS)
Hardin, Perry J.; Long, David G.
1993-08-01
Since 1978, AVHRR imagery from NOAA polar orbiters has provided coverage of tropical regions at this desirable resolution, but much of the imagery is plagued with heavy cloud cover typical of equatorial regions. Clearly a medium resolution radar sensor would be a useful addition to AVHRR, but none are planned to fly in the future. In contrast, scatterometers are an important radar component of many future earth remote sensing systems, but the inherent resolution of these instruments is too low (approximately equals 50 km) for monitoring earth's land surfaces. However, a recently developed image reconstruction technique can increase the spatial resolution of scatterometer data to levels (approximately equals 4 to 14 km) approaching AVHRR global area coverage (approximately equals 4 km). When reconstructed, scatterometer data may prove to be an important asset in evaluating equatorial land cover. In this paper, the authors compare the utility of reconstructed Seasat scatterometer (SASS), Ku-band microwave data to reconstructed ERS-1 C-band scatterometer imagery for discrimination and monitoring of tropical vegetation formations. In comparative classification experiments conducted on reconstructed images of Brasil, the ERS-1 C-band imagery was slightly superior to its reconstructed SASS Ku-band counterpart for discriminating between several equatorial land cover classes. A classification accuracy approaching .90 was achieved when the two scatterometer images were combined with an AVHRR normalized difference vegetation index (NDVI) image. The success of these experiments indicates that further research into reconstructed image applications to tropical forest monitoring is warranted.
Global trends in neglected tropical disease control and elimination: impact on child health.
Barry, Meagan A; Simon, Gregory G; Mistry, Neeraj; Hotez, Peter J
2013-08-01
The neglected tropical diseases (NTDs) are a group of 17 lesser known chronic infections which predominantly affect poor and disenfranchised communities. There are a number of NTDs that cause significant global morbidity in children, including the three major soil transmitted helminth (STH) infections (ascariasis, trichuriasis and hookworm infection), schistosomiasis and trachoma. These NTDs, together with lymphatic filariasis and onchocerciasis, are currently being targeted for global control and elimination through mass drug administration (MDA) campaigns. They represent the most common NTDs and share significant geographical overlap. Additionally, many individuals are polyparasitised with more than a single NTD. Integrated NTD control and elimination MDA programmes offer safe and efficacious treatments for all seven NTDs. However, the current global level of MDA coverage for the leading childhood NTDs, that is, STH infections, schistosomiasis and trachoma, remains well under 50%. Limiting factors for global coverage include insufficient global financial support, drug donation capacity of pharmaceutical companies and targeting school age children to the exclusion of other age groups in need of treatment, such as preschool age children. There is also a need for development of novel prevention and treatment modalities, such as next-generation small molecule drugs and vaccines. Efforts are underway to harness the momentum of a 2012 London Declaration on NTDs and a 2013 World Health Assembly (WHA) resolution as a means to control or in some cases eliminate by 2020 these NTDs that affect children worldwide.
NASA Astrophysics Data System (ADS)
Iwahashi, J.; Yamazaki, D.; Matsuoka, M.; Thamarux, P.; Herrick, J.; Yong, A.; Mital, U.
2017-12-01
A seamless model of landform classifications with regional accuracy will be a powerful platform for geophysical studies that forecast geologic hazards. Spatial variability as a function of landform on a global scale was captured in the automated classifications of Iwahashi and Pike (2007) and additional developments are presented here that incorporate more accurate depictions using higher-resolution elevation data than the original 1-km scale Shuttle Radar Topography Mission digital elevation model (DEM). We create polygon-based terrain classifications globally by using the 280-m DEM interpolated from the Multi-Error-Removed Improved-Terrain DEM (MERIT; Yamazaki et al., 2017). The multi-scale pixel-image analysis method, known as Multi-resolution Segmentation (Baatz and Schäpe, 2000), is first used to classify the terrains based on geometric signatures (slope and local convexity) calculated from the 280-m DEM. Next, we apply the machine learning method of "k-means clustering" to prepare the polygon-based classification at the globe-scale using slope, local convexity and surface texture. We then group the divisions with similar properties by hierarchical clustering and other statistical analyses using geological and geomorphological data of the area where landslides and earthquakes are frequent (e.g. Japan and California). We find the 280-m DEM resolution is only partially sufficient for classifying plains. We nevertheless observe that the categories correspond to reported landslide and liquefaction features at the global scale, suggesting that our model is an appropriate platform to forecast ground failure. To predict seismic amplification, we estimate site conditions using the time-averaged shear-wave velocity in the upper 30-m (VS30) measurements compiled by Yong et al. (2016) and the terrain model developed by Yong (2016; Y16). We plan to test our method on finer resolution DEMs and report our findings to obtain a more globally consistent terrain model as there are known errors in DEM derivatives at higher-resolutions. We expect the improvement in DEM resolution (4 times greater detail) and the combination of regional and global coverage will yield a consistent dataset of polygons that have the potential to improve relations to the Y16 estimates significantly.
NASA Astrophysics Data System (ADS)
Shen, S. S.
2015-12-01
This presentation describes the detection of interdecadal climate signals in a newly reconstructed precipitation data from 1850-present. Examples are on precipitation signatures of East Asian Monsoon (EAM), Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillations (AMO). The new reconstruction dataset is an enhanced edition of a suite of global precipitation products reconstructed by Spectral Optimal Gridding of Precipitation Version 1.0 (SOGP 1.0). The maximum temporal coverage is 1850-present and the spatial coverage is quasi-global (75S, 75N). This enhanced version has three different temporal resolutions (5-day, monthly, and annual) and two different spatial resolutions (2.5 deg and 5.0 deg). It also has a friendly Graphical User Interface (GUI). SOGP uses a multivariate regression method using an empirical orthogonal function (EOF) expansion. The Global Precipitation Climatology Project (GPCP) precipitation data from 1981-20010 are used to calculate the EOFs. The Global Historical Climatology Network (GHCN) gridded data are used to calculate the regression coefficients for reconstructions. The sampling errors of the reconstruction are analyzed according to the number of EOF modes used in the reconstruction. Our reconstructed 1900-2011 time series of the global average annual precipitation shows a 0.024 (mm/day)/100a trend, which is very close to the trend derived from the mean of 25 models of the CMIP5 (Coupled Model Intercomparison Project Phase 5). Our reconstruction has been validated by GPCP data after 1979. Our reconstruction successfully displays the 1877 El Nino (see the attached figure), which is considered a validation before 1900. Our precipitation products are publically available online, including digital data, precipitation animations, computer codes, readme files, and the user manual. This work is a joint effort of San Diego State University (Sam Shen, Gregori Clarke, Christian Junjinger, Nancy Tafolla, Barbara Sperberg, and Melanie Thorn), UCLA (Yongkang Xue), and University of Maryland (Tom Smith and Phil Arkin) and supported in part by the U.S. National Science Foundation (Awards No. AGS-1419256 and AGS-1015957).
International river basins of the world
Wolf, Aaron T.; Natharius, Jeffrey A.; Danielson, Jeffrey J.; Ward, Brian S.; Pender, Jan K.
1999-01-01
It is becoming acknowledged that water is likely to be the most pressing environmental concern of the next century. Difficulties in river basin management are only exacerbated when the resource crosses international boundaries. One critical aid in the assessment of international waters has been the Register of International Rivers a compendium which listed 214 international waterways that cover 47% of the earth's continental land surface. The Register, though, was last updated in 1978 by the now defunct United Nations Department of Economic and Social Affairs. The purpose of this paper is to update the Register in order to reflect the quantum changes that have taken place over the last 22 years, both in global geopolitics and in map coverage and technology. By accessing digital elevation models at spatial resolutions of 30 arc seconds, corroborating at a unified global map coverage of at least 1:1 000 000, and superimposing the results over complete coverage of current political boundaries, we are able to provide a new register which lists 261 international rivers, covering 45.3% of the land surface of the earth (excluding Antarctica). This paper lists all international rivers with their watershed areas, the nations which share each watershed,their respective territorial percentages, and notes on changes in or disputes over international boundaries since 1978.
NASA Technical Reports Server (NTRS)
Patterson, G. Wesley; Head, James W.; Collins, Geoffrey C.; Pappalardo, Robert T.; Prockter, Louis M.; Lucchitta, Baerbel K.
2008-01-01
In the coming year a global geological map of Ganymede will be completed that represents the most recent understanding of the satellite on the basis of Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. Material units have been defined, structural landforms have been identified, and an approximate stratigraphy has been determined utilizing a global mosaic of the surface with a nominal resolution of 1 km/pixel assembled by the USGS. This mosaic incorporates the best available Voyager and Galileo regional coverage and high resolution imagery (100-200 m/pixel) of characteristic features and terrain types obtained by the Galileo spacecraft. This map has given us a more complete understanding of: 1) the major geological processes operating on Ganymede, 2) the characteristics of the geological units making up its surface, 3) the stratigraphic relationships of geological units and structures, and 4) the geological history inferred from these relationships. A summary of these efforts is provided here.
NASA Astrophysics Data System (ADS)
McDonald, K. C.; Jensen, K.; Schroeder, R.; Tessler, Z. D.
2016-12-01
Surface inundation extent and its predictability vary tremendously across the globe. This dynamic is being and has been captured by three general categories of satellite imagery: a) low-spatial-resolution microwave sensors with global coverage and a long record of observations (e.g., SSM/I), b) optical sensors with high spatial and temporal resolution and global coverage as well, but with cloud contamination (e.g. MODIS), and also c) less frequently in ``snapshot'' form by high-resolution synthetic aperture radar (SAR) sensors. We explore the ability to bridge techniques that can exploit the higher spatial resolution of more recent data products back in time with the help of the temporal evolution of lower resolution products. We present a study of long term (20+ yrs) inundation patterns in two river deltas: (1) the Mekong, and (2) the Ganges-Brahmaputra. This research utilizes baseline observations from the Surface Water Microwave Product Series (SWAMPS), an inundation area fraction product derived at 25km scale from active and passive microwave instruments (ERS, QuikSCAT, ASCAT, and SSM/I) that spans from Jan 1992 to the present. Every hydrological basin has unique characteristics - such as its topography, land cover / land use, and spatio-temporal variability - thus, a downscaling algorithm needs to take into account these idiosyncrasies. We merge SWAMPS with topographical information derived from 30m SRTM DEM, river networks from USGS HydroSHEDS, and train a downscaling algorithm to learn from two sets of classified SAR data: (1) L-band imaging radar from ALOS PALSAR, 2007-2010, and (2) more recent C-band imagery from the Sentinel-1 mission (2014 to present). We present an accuracy assessment of retrospective downscaled flood extent with Landsat imagery and address potential sources of biases. With a higher spatial resolution of past flooding extent, we can improve our understanding of how delta surface hydrology has responded to climate events and human activities. This is important both in the short-term for accurate flood prediction, as well as on longer-term planning horizons.
MESSENGER at Mercury: Early Orbital Operations
NASA Technical Reports Server (NTRS)
McNutt, Ralph L., Jr; Solomon, Sean C.; Bedini, Peter D.; Anderson, Brian J.; Blewett, David T.; Evans, Larry G.; Gold, Robert E.; Krimigis, Stamatios M.; Murchie, Scott L.; Nittler, Larry R.;
2013-01-01
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90% coverage and at least 250 m average resolution, a global color image mosaic at better than 90% coverage and at least 1 km average resolution, and global stereo imaging at better than 80% coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 20 deg. S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation.
MESSENGER at Mercury: Early Orbital Operations
NASA Technical Reports Server (NTRS)
McNutt, Ralph L., Jr.; Solomon, Sean C.; Bedini, Peter D.; Anderson, Brian J.; Blewett, David T.; Evans, Larry G.; Gold, Robert E.; Krimigis, Stamatios M.; Murchie, Scott L.; Nittler, Larry R.;
2012-01-01
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 under NASA's Discovery Program, was inserted into orbit about the planet Mercury in March 2011. MESSENGER's three flybys of Mercury in 2008-2009 marked the first spacecraft visits to the innermost planet since the Mariner 10 flybys in 1974-1975. The unprecedented orbital operations are yielding new insights into the nature and evolution of Mercury. The scientific questions that frame the MESSENGER mission led to the mission measurement objectives to be achieved by the seven payload instruments and the radio science experiment. Interweaving the full set of required orbital observations in a manner that maximizes the opportunity to satisfy all mission objectives and yet meet stringent spacecraft pointing and thermal constraints was a complex optimization problem that was solved with a software tool that simulates science observations and tracks progress toward meeting each objective. The final orbital observation plan, the outcome of that optimization process, meets all mission objectives. MESSENGER's Mercury Dual Imaging System is acquiring a global monochromatic image mosaic at better than 90%coverage and at least 250 m average resolution, a global color image mosaic at better than 90%coverage and at least 1 km average resolution, and global stereo imaging at better than 80%coverage and at least 250 m average resolution. Higher-resolution images are also being acquired of targeted areas. The elemental remote sensing instruments, including the Gamma-Ray and Neutron Spectrometer and the X-Ray Spectrometer, are being operated nearly continuously and will establish the average surface abundances of most major elements. The Visible and Infrared Spectrograph channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer is acquiring a global map of spectral reflectance from 300 to 1450 nm wavelength at a range of incidence and emission angles. Targeted areas have been selected for spectral coverage into the ultraviolet with the Ultraviolet and Visible Spectrometer (UVVS). MESSENGER's Mercury Laser Altimeter is acquiring topographic profiles when the slant range to Mercury's surface is less than 1800 km, encompassing latitudes from 201S to the north pole. Topography over the remainder of the southern hemisphere will be derived from stereo imaging, radio occultations, and limb profiles. MESSENGER's radio science experiment is determining Mercury's gravity field from Doppler signals acquired during frequent downlinks. MESSENGER's Magnetometer is measuring the vector magnetic field both within Mercury's magnetosphere and in Mercury's solar wind environment at an instrument sampling rate of up to 20 samples/s. The UVVS is determining the three-dimensional, time-dependent distribution of Mercury's exospheric neutral and ionic species via their emission lines. During each spacecraft orbit, the Energetic Particle Spectrometer measures energetic electrons and ions, and the Fast Imaging Plasma Spectrometer measures the energies and mass per charge of thermal plasma components, both within Mercury's magnetosphere and in Mercury's solar-wind environment. The primary mission observation sequence will continue for one Earth year, until March 2012. An extended mission, currently under discussion with NASA, would add a second year of orbital observations targeting a set of focused follow-on questions that build on observations to date and take advantage of the more active Sun expected during 2012-2013. MESSENGER's total primary mission cost, projected at $446 M in real-year dollars, is comparable to that of Mariner 10 after adjustment for inflation.
NASA Astrophysics Data System (ADS)
Ashouri, H.; Hsu, K.; Sorooshian, S.; Braithwaite, D.; Knapp, K. R.; Cecil, L. D.
2013-12-01
PERSIANN Climate Data Record (PERSIANN-CDR) is a new retrospective satellite-based precipitation data set that is constructed for long-term hydrological and climate studies. The PERSIANN-CDR is a near-global (60°S-60°N) long-term (1980-2012), multi-satellite, high-resolution precipitation product that provides rain rate estimates at 0.25° and daily spatiotemporal resolution. PERSIANN-CDR is aimed at addressing the need for a consistent, long-term, high resolution precipitation data set for studying the spatial and temporal variations and changes of precipitation patterns, particularly in a scale relevant to climate extremes at the global scale. PERSIANN-CDR is generated from the PERSIANN algorithm using GridSat-B1 infrared data from the International Satellite Cloud Climatology Project (ISCCP). PERSIANN-CDR is adjusted using the Global Precipitation Climatology Project (GPCP) monthly precipitation to maintain consistency of two data sets at 2.5° monthly scale throughout the entire reconstruction period. PERSIANN-CDR daily precipitation data demonstrates considerable consistency with both GPCP monthly and GPCP 1DD precipitation products. Verification studies over Hurricane Katrina show that PERSIANN-CDR has a good agreement with NCEP Stage IV radar data, noting that PERSIANN-CDR has better spatial coverage. In addition, the Probability Density Function (PDF) of PERSIANN-CDR over the contiguous United States was compared with the PDFs extracted from CPC gauge data and the TMPA precipitation product. The experiment also shows good agreement of the PDF of PERSIANN-CDR with the PDFs of TMPA and CPC gauge data. The application of PERSIANN-CDR in regional and global drought monitoring is investigated. Consisting of more than three decades of high-resolution precipitation data, PERSIANN-CDR makes us capable of long-term assessment of droughts at a higher resolution (0.25°) than previously possible. The results will be presented at the meeting.
Lunar geodesy and cartography: a new era
NASA Astrophysics Data System (ADS)
Duxbury, Thomas; Smith, David; Robinson, Mark; Zuber, Maria T.; Neumann, Gregory; Danton, Jacob; Oberst, Juergen; Archinal, Brent; Glaeser, Philipp
The Lunar Reconnaissance Orbiter (LRO) ushers in a new era in precision lunar geodesy and cartography. LRO was launched in June, 2009, completed its Commissioning Phase in Septem-ber 2009 and is now in its Primary Mission Phase on its way to collecting high precision, global topographic and imaging data. Aboard LRO are the Lunar Orbiter Laser Altimeter (LOLA -Smith, et al., 2009) and the Lunar Reconnaissance Orbiter Camera (LROC -Robinson, et al., ). LOLA is a derivative of the successful MOLA at Mars that produced the global reference surface being used for all precision cartographic products. LOLA produces 5 altimetry spots having footprints of 5 m at a frequency of 28 Hz, significantly bettering MOLA that produced 1 spot having a footprint of 150 m at a frequency of 10 Hz. LROC has twin narrow angle cameras having pixel resolutions of 0.5 meters from a 50 km orbit and a wide-angle camera having a pixel resolution of 75 m and in up to 7 color bands. One of the two NACs looks to the right of nadir and the other looks to the left with a few hundred pixel overlap in the nadir direction. LOLA is mounted on the LRO spacecraft to look nadir, in the overlap region of the NACs. The LRO spacecraft has the ability to look nadir and build up global coverage as well as looking off-nadir to provide stereo coverage and fill in data gaps. The LROC wide-angle camera builds up global stereo coverage naturally from its large field-of-view overlap from orbit to orbit during nadir viewing. To date, the LROC WAC has already produced global stereo coverage of the lunar surface. This report focuses on the registration of LOLA altimetry to the LROC NAC images. LOLA has a dynamic range of tens of km while producing elevation data at sub-meter precision. LOLA also has good return in off-nadir attitudes. Over the LRO mission, multiple LOLA tracks will be in each of the NAC images at the lunar equator and even more tracks in the NAC images nearer the poles. The registration of LOLA altimetry to NAC images is aided by the 5 spots showing regional and local slopes, along and cross-track, that are easily correlated visually to features within the images. Once can precisely register each of the 5 LOLA spots to specific pixels in LROC images of distinct features such as craters and boulders. This can be performed routinely for features at the 100 m level and larger. However, even features at the several m level can also be registered if a single LOLA spots probes the depth of a small crater while the other 4 spots are on the surrounding surface or one spot returns from the top of a small boulder seen by NAC. The automatic registration of LOLA tracks with NAC stereo digital terrain models should provide for even higher accuracy. Also the LOLA pulse spread of the returned signal, which is sensitive to slopes and roughness, is an additional source of information to help match the LOLA tracks to the images As the global coverage builds, LOLA will provide absolute coordinates in latitude, longitude and radius of surface features with accuracy at the meter level or better. The NAC images will then be reg-istered to the LOLA reference surface in the production of precision, controlled photomosaics, having spatial resolutions as good as 0.5 m/pixel. For hundreds of strategic sites viewed in stereo, even higher precision and more complete surface coverage is possible for the produc-tion of digital terrain models and mosaics. LRO, with LOLA and LROC, will improve the relative and absolute accuracy of geodesy and cartography by orders of magnitude, ushering in a new era for lunar geodesy and cartography. Robinson, M., et al., Space Sci. Rev., DOI 10.1007/s11214-010-9634-2, Date: 2010-02-23, in press. Smith, D., et al., Space Sci. Rev., DOI 10.1007/s11214-009-9512-y, published online 16 May 2009.
NASA Astrophysics Data System (ADS)
Ticehurst, C. J.; Bartsch, A.; Doubkova, M.; van Dijk, A. I. J. M.
2009-11-01
Continuous flood monitoring can support emergency response, water management and environmental monitoring. Optical sensors such as MODIS allow inundation mapping with high spatial and temporal resolution (250-1000 m, twice daily) but are affected by cloud cover. Passive microwave sensors also acquire observations at high temporal resolution, but coarser spatial resolution (e.g. ca. 5-70 km for AMSR-E) and smaller footprints are also affected by cloud and/or rain. ScanSAR systems allow all-weather monitoring but require spatial resolution to be traded off against coverage and/or temporal resolution; e.g. the ENVISAT ASAR Global Mode observes at ca. 1 km over large regions about twice a week. The complementary role of the AMSR-E and ASAR GM data to that of MODIS is here introduced for three flood events and locations across Australia. Additional improvements can be made by integrating digital elevation models and stream flow gauging data.
The GODAE High Resolution Sea Surface Temperature Pilot Project (GHRSST-PP)
NASA Astrophysics Data System (ADS)
Donlon, C.; Ghrsst-Pp Science Team
2003-04-01
This paper summarises Development and Implementation Plan of the GODAE High Resolution Sea Surface Temperature Pilot Project (GHRSST-PP). The aim of the GHRSST-PP is to coordinate a new generation of global, multi-sensor, high-resolution (better than 10 km and 12 hours) SST products for the benefit of the operational and scientific community and for those with a potential interest in the products of GODAE. The GHRSST-PP project will deliver a demonstration system that integrates data from existing international satellite and in situ data sources using state-of-the-art communications and analysis tools. Primary GHRSST-PP products will be generated by fusing infrared and microwave satellite data obtained from sensors in near polar, geostationary and low earth orbits, constrained by in situ observations. Surface skin SST, sub-surface SST and SST at depth will be produced as both merged and analysed data products. Merged data products have a common grid but all input data retaining their error statistics whereas analysed data products use all data to derive a best estimate data source having one set of error statistics. Merged SST fields will not be interpolated thereby preserving the integrity of the source data as much as possible. Products will be first produced and validated using in situ observations for regional areas by regional data assembly centres (RDAC) and sent to a global data analysis centre (GDAC) for integration with other data to provide global coverage. GDAC and RDAC will be connected together with other data using a virtual dynamic distributed database (DDD). The GDAC will merge and analyse RDAC data together with other data (from the GTS and space agencies) to provide global coverage every 12 hours in real time. In all cases data products will be accurate to better than 0.5 K validated using data collected at globally distributed diagnostic data set (DDS) sites. A user information service (UIS) will work together with user applications and services (AUS) to ensure that the GHRSST-PP is able to respond appropriately to user demands. In addition, the GDAC will provide product validation and dissemination services as well as the means for researchers to test and use the In situ and Satellite Data Integration Processing Model (ISDI-PM) operational demonstration code using a large supercomputer.
Effects of daily, high spatial resolution a priori profiles of satellite-derived NOx emissions
NASA Astrophysics Data System (ADS)
Laughner, J.; Zare, A.; Cohen, R. C.
2016-12-01
The current generation of space-borne NO2 column observations provides a powerful method of constraining NOx emissions due to the spatial resolution and global coverage afforded by the Ozone Monitoring Instrument (OMI). The greater resolution available in next generation instruments such as TROPOMI and the capabilities of geosynchronous platforms TEMPO, Sentinel-4, and GEMS will provide even greater capabilities in this regard, but we must apply lessons learned from the current generation of retrieval algorithms to make the best use of these instruments. Here, we focus on the effect of the resolution of the a priori NO2 profiles used in the retrieval algorithms. We show that for an OMI retrieval, using daily high-resolution a priori profiles results in changes in the retrieved VCDs up to 40% when compared to a retrieval using monthly average profiles at the same resolution. Further, comparing a retrieval with daily high spatial resolution a priori profiles to a more standard one, we show that emissions derived increase by 100% when using the optimized retrieval.
Harmonizing Landsat and Sentinel-2 Reflectances for Better Land Monitoring
NASA Technical Reports Server (NTRS)
Masek, Jeffrey; Vermote, Eric; Franch, Belen; Roger, Jean-Claude; Skakun, Sergii; Claverie, Martin; Dungan, Jennifer
2016-01-01
When combined, Landsat and ESA Sentinel-2 observations can provide 2-4 day coverage for the global land area. A collaboration among NASA GSFC (Goddard Space Flight Center), University of Maryland, and NASA Ames has developed a processing chain to create seamless, "harmonized" reflectance products using standardized atmospheric correction, BRDF (Bidirectional Reflectance Distribution Function) adjustment, spectral bandpass adjustment, and gridding algorithms. These products point the way to a "30-m MODIS (Moderate Resolution Imaging Spectroradiometer)" capability for agricultural and ecosystem monitoring by leveraging international sensors.
USGS Releases Landsat Orthorectified State Mosaics
,
2005-01-01
The U.S. Geological Survey (USGS) National Remote Sensing Data Archive, located at the USGS Center for Earth Resources Observation and Science (EROS) in Sioux Falls, South Dakota, maintains the Landsat orthorectified data archive. Within the archive are Landsat Enhanced Thematic Mapper Plus (ETM+) data that have been pansharpened and orthorectified by the Earth Satellite Corporation. This imagery has acquisition dates ranging from 1999 to 2001 and was created to provide users with access to quality-screened, high-resolution satellite images with global coverage over the Earth's landmasses.
Landsat 7 - A challenge to America
NASA Astrophysics Data System (ADS)
Colvocoresses, Alden P.
Factors in favor of Landsat 7 are discussed; they include: reasonable cost, a base on which to examine global change, and the need for comprehensive and continuous satellite coverage of the earth at moderate (5-30 m) resolution, in view of various occurrences on the earth's surface, ranging from the Chernobyl disaster to deforestation to the Persian Gulf conflict. Attention is given to proposed parameters for Landsat 7 and suggested actions that should be taken by Congress, the Administration, and the public to implement this space program.
2015-01-31
VANDENBERG AIR FORCE BASE, Calif. – The two-stage Delta II launch vehicle lifts off Space Launch Complex 2 at Vandenberg Air Force Base, carrying NASA's Soil Moisture Active Passive satellite, or SMAP, on a mission to study global coverage of soil moisture and freeze/thaw measurements. Launch was at 9:22 a.m. EST. SMAP is designed to produce the highest-resolution maps of soil moisture ever obtained from space. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett
NASA Astrophysics Data System (ADS)
Sun, Wei; Tobehn, Carsten; Ernst, Robert; Bovensmann, Heinrich; Buchwitz, Michael; Burrows, John P.; Notholt, John
1 Carbon dioxide (CO2) and methane (CH4) are the most important manmade greenhouse gases (GHGs) which are driving global climate change. Currently, the CO2 measurements from the ground observing network are still the main sources of information but due to the limited number of measurement stations the coverage is limited. In addition, CO2 monitoring and trading is often based mainly on bottom-up calculations and an independent top down verification is limited due to the lack of global measurement data with local resolution. The first CO2 and CH4 mapping from SCIAMACHY on ENVISAT shows that satellites add important missing global information. Current GHG measurement satellites (GOSAT)are limited either in spatial or temporal resolution and coverage. These systems have to collect data over a year or even longer to produce global regional fluxes products. Conse-quently global, timely, higher spatial resolution and high accuracy measurement are required for: 1. A good understanding of the CO2 and CH4 sources and sinks for reliable climate predic-tion; and 2. Independent and transparent verification of accountable sources and sinks in supporting Kyoto and upcoming protocols The CarbonSat constellation idea comes out the trade off of resolution and swath width during CarbonSat mission definition studies. In response to the urgent need to support the Kyoto and upcoming protocols, a feasibility study has been carried out. The proposed solution is a constellation of five CarbonSat satellites in 614km LTAN 13:00, which is able to provide global, daily CO2 and CH4 measurement everywhere on the Earth with high spatial resolution 2 × 2 km and low uncertainty lt;2ppm (CO2) and lt;8ppb (CH4). The unique global daily measurement capability significantly increases the number of cloud free measurements, which enables more reliable services associated with reduced uncertainty, e.g. to 0.15ppm (CO2) per month in 10km and even more timely products. The CarbonSat Constellation in combination with inverse modelling techniques will be able to provide information services, such as global quarterly 1. CO2 and CH4 regional flux updates 2. CO2 emission reporting from hot spots e.g. the power plant 3. CH4 emission reporting from hot spots e.g. the pipeline/oil and gas fields. The team led by the industry partner -OHB now promotes an internationally coordinated CarbonSat constellation to provide operational services contributing to the independent iden-tification and verification of man-made & natural CO2 and CH4 emissions and claimed carbon sinks. It is proposed that the CarbonSat Constellation will be implemented through an internation-ally coordinated constellation. Each country contributes one satellite in the constellation and establishes its own ground station to provide data for national applications. A central coordi-nation will be set up for the constellation operation, data calibration and international data distribution. The proposed approach provides independence for each partner and is financially more feasible. In addition, the CarbonSat Constellation consortium could be a bridge/forum between developed countries and developing countries in establishing common understandings of and actions on the global climate change. The world wide transparency provided by this international forum is also critical in supporting Kyoto protocol and upcoming international agreement in man-made Greenhouse emission reduction. The paper will present the CarbonSat Constellation design and the proposed products/ services to verify CO2 and CH4 sources and sinks from a constellation of five CarbonSat satellites through a multilateral collaboration.
Global Monitoring of Air Pollution Using Spaceborne Sensors
NASA Technical Reports Server (NTRS)
Chu, D. A.; Kaufman, Y. J.; Tanre, D.; Remer, L. A.; Einaudi, Franco (Technical Monitor)
2000-01-01
The MODIS sensor onboard EOS-Terra satellite provides not only daily global coverage but also high spectral (36 channels from 0.41 to 14 microns wavelength) and spatial (250m, 500m and 1km) resolution measurements. A similar MODIS instrument will be also configured into EOS-Aqua satellite to be launched soon. Using the complementary EOS-Terra and EOS-Aqua sun-synchronous orbits (10:30 AM and 1:30 PM equator-crossing time respectively), it enables us also to study the diurnal changes of the Earth system. It is unprecedented for the derivation of aerosol properties with such high spatial resolution and daily global converge. Aerosol optical depth and other aerosol properties, e.g., Angstrom coefficient over land and particle size over ocean, are derived as standard products at a spatial resolution of 10 x 10 sq km. The high resolution results are found surprisingly useful in detecting aerosols in both urban and rural regions as a result of urban/industrial pollution and biomass burning. For long-lived aerosols, the ability to monitoring the evolution of these aerosol events could help us to establish an system of air quality especially for highly populated areas. Aerosol scenarios with city pollution and biomass burning will be presented. Also presented are the method used in the derivation of aerosol optical properties and preliminary results will be presented, and issue as well as obstacles in validating aerosol optical depth with AERONET ground-based observations.
Trade-off studies of a hyperspectral infrared sounder on a geostationary satellite.
Wang, Fang; Li, Jun; Schmit, Timothy J; Ackerman, Steven A
2007-01-10
Trade-off studies on spectral coverage, signal-to-noise ratio (SNR), and spectral resolution for a hyperspectral infrared (IR) sounder on a geostationary satellite are summarized. The data density method is applied for the vertical resolution analysis, and the rms error between true and retrieved profiles is used to represent the retrieval accuracy. The effects of spectral coverage, SNR, and spectral resolution on vertical resolution and retrieval accuracy are investigated. The advantages of IR and microwave sounder synergy are also demonstrated. When focusing on instrument performance and data processing, the results from this study show that the preferred spectral coverage combines long-wave infrared (LWIR) with the shorter middle-wave IR (SMidW). Using the appropriate spectral coverage, a hyperspectral IR sounder with appropriate SNR can achieve the required science performance (1 km vertical resolution, 1 K temperature, and 10% relative humidity retrieval accuracy). The synergy of microwave and IR sounders can improve the vertical resolution and retrieval accuracy compared to either instrument alone.
NASA Astrophysics Data System (ADS)
Gasiewski, A. J.; Sanders, B. T.; Gallaher, D. W.; Periasamy, L.; Alvarenga, G.; Weaver, R.; Scambos, T. A.
2014-12-01
PolarCube is a 3U CubeSat based on the CU ALL-STAR bus hosting an eight-channel passive microwave scanning spectrometer operating at the 118.7503 GHz (1-) O2 resonance. The anticipated launch date is in late 2015. It is being designed to operate for 12 months on orbit to provide global 118-GHz spectral imagery of the Earth over a full seasonal cycle. The mission will focus on the study of Arctic vertical temperature structure and its relation to sea ice coverage, but include the secondary goals of assessing the potential for convective cloud mass detection and cloud top altitude measurement and hurricane warm core sounding. The principles used by PolarCube for sounding and cloud measurement have been well established in number of peer-reviewed papers, although measurements using the 118 GHz oxygen line over the dry polar regions (unaffected by water vapor) have never been demonstrated from space. The PolarCube channels are selected to probe clear-air emission over vertical levels from the surface to the lower stratosphere. Operational spaceborne microwave soundings have available for decades but using lower frequencies (50-57 GHz) and from higher altitudes. While the JPSS ATMS sensor provides global coverage at ~32 km resolution PolarCube will improve on this resolution by a factor of two (~16 km), thus facilitating a key science goal of mapping sea ice concentration and extent while obtaining temperature profile data. Additionally, we seek to correlate freeze-thaw line data from the NASA SMAP mission with atmospheric temperature structure to help understand the relationship between clouds, temperature, and surface energy fluxes during seasonal transitions. PolarCube will also provide the first demonstration of a very low cost passive microwave sounder that if operated in a fleet configuration would have the potential to fulfill the goals of the Precipitation Atmospheric Temperature and Humidity (PATH) mission, as defined in the NRC Decadal Survey.
Feasibility of blocking detection in observations from radio occultation
NASA Astrophysics Data System (ADS)
Brunner, Lukas; Steiner, Andrea Karin; Scherllin-Pirscher, Barbara; Jury, Martin
2015-04-01
Blocking describes an atmospheric situation in which the climatological westerly flow at mid latitudes is weakened or reversed. This is caused by a persistent high pressure system which can be stationary for several days to weeks. In the Northern Hemisphere blocking preferably occurs over the Atlantic/European and the Pacific regions. In recent years blocking has been under close scientific investigation due to its effect on weather extremes, triggering heat waves in summer and cold spells in winter. So far, scientific literature mainly focused on the investigation of blocking in reanalysis and global climate model data sets. However, blocking is underestimated in most climate models due to small-scale processes involved in its evolution. For a detection of blocking, most commonly applied methods are based on the computation of meridional geopotential height gradients at the 500 hPa level. Therefore measurements with adequate vertical, horizontal, and temporal resolution and coverage are required. We use an observational data set based on Global Positioning System (GPS) Radio Occultation (RO) measurements fulfilling these requirements. RO is a relatively new, satellite based remote sensing technique, delivering profiles of atmospheric parameters such as geopotential height, pressure, and temperature. It is characterized by favorable properties like long-term stability, global coverage, and high vertical resolution. Our data set is based on the most recent WEGC RO retrieval. Here we report on a feasibility study for blocking detection and analysis in RO data for two exemplary blocking events: the blocking over Russia in summer 2010 and the blocking over Greenland in late winter 2013. For these two events about 700 RO measurements per day are available in the Northern Hemisphere. We will show that the measurement density and quality of RO observations are favorable for blocking analysis and can therefore contribute to blocking research.
Mapping wood density globally using remote sensing and climatological data
NASA Astrophysics Data System (ADS)
Moreno, A.; Camps-Valls, G.; Carvalhais, N.; Kattge, J.; Robinson, N.; Reichstein, M.; Allred, B. W.; Running, S. W.
2017-12-01
Wood density (WD) is defined as the oven-dry mass divided by fresh volume, varies between individuals, and describes the carbon investment per unit volume of stem. WD has been proven to be a key functional trait in carbon cycle research and correlates with numerous morphological, mechanical, physiological, and ecological properties. In spite of the utility and importance of this trait, there is a lack of an operational framework to spatialize plant WD measurements at a global scale. In this work, we present a consistent modular processing chain to derive global maps (500 m) of WD using modern machine learning techniques along with optical remote sensing data (MODIS/Landsat) and climate data using the Google Earth Engine platform. The developed approach uses a hierarchical Bayesian approach to fill in gaps in the plant measured WD data set to maximize its global representativeness. WD plant species are then aggregated to Plant Functional Types (PFT). The spatial abundance of PFT at 500 m spatial resolution (MODIS) is calculated using a high resolution (30 m) PFT map developed using Landsat data. Based on these PFT abundances, representative WD values are estimated for each MODIS pixel with nearby measured data. Finally, random forests are used to globally estimate WD from these MODIS pixels using remote sensing and climate. The validation and assessment of the applied methods indicate that the model explains more than 72% of the spatial variance of the calculated community aggregated WD estimates with virtually unbiased estimates and low RMSE (<15%). The maps thus offer new opportunities to study and analyze the global patterns of variation of WD at an unprecedented spatial coverage and spatial resolution.
Global metabolic profiling procedures for urine using UPLC-MS.
Want, Elizabeth J; Wilson, Ian D; Gika, Helen; Theodoridis, Georgios; Plumb, Robert S; Shockcor, John; Holmes, Elaine; Nicholson, Jeremy K
2010-06-01
The production of 'global' metabolite profiles involves measuring low molecular-weight metabolites (<1 kDa) in complex biofluids/tissues to study perturbations in response to physiological challenges, toxic insults or disease processes. Information-rich analytical platforms, such as mass spectrometry (MS), are needed. Here we describe the application of ultra-performance liquid chromatography-MS (UPLC-MS) to urinary metabolite profiling, including sample preparation, stability/storage and the selection of chromatographic conditions that balance metabolome coverage, chromatographic resolution and throughput. We discuss quality control and metabolite identification, as well as provide details of multivariate data analysis approaches for analyzing such MS data. Using this protocol, the analysis of a sample set in 96-well plate format, would take ca. 30 h, including 1 h for system setup, 1-2 h for sample preparation, 24 h for UPLC-MS analysis and 1-2 h for initial data processing. The use of UPLC-MS for metabolic profiling in this way is not faster than the conventional HPLC-based methods but, because of improved chromatographic performance, provides superior metabolome coverage.
NASA Technical Reports Server (NTRS)
Obrien, S. O. (Principal Investigator)
1980-01-01
The program, LACVIN, calculates vegetative indexes numbers on limited area coverage/high resolution picture transmission data for selected IJ grid sections. The IJ grid sections were previously extracted from the full resolution data tapes and stored on disk files.
ERIC Educational Resources Information Center
David, Matthew
2016-01-01
UK media coverage of global university league tables shows systematic bias towards the Russell Group, although also highlighting tensions within its membership. Coverage positions UK "elite" institutions between US superiority and Asian ascent. Coverage claims that league table results warrant UK university funding reform. However,…
Enabling Characteristics Of Optical Autocovariance Lidar For Global Wind And Aerosol Profiling
NASA Astrophysics Data System (ADS)
Grund, C. J.; Stephens, M.; Lieber, M.; Weimer, C.
2008-12-01
Systematic global wind measurements with 70 km horizontal resolution and, depending on altitude from the PBL to stratosphere, 250m-2km vertical resolution and 0.5m/s - 2 m/s velocity precision are recognized as key to the understanding and monitoring of complex climate modulations, validation of models, and improved precision and range for weather forecasts. Optical Autocovariance Wind Lidar (OAWL) is a relatively new interferometric direct detection Doppler lidar approach that promises to meet the required wind profile resolution at substantial mass, cost, and power savings, and at reduced technical risk for a space-based system meeting the most demanding velocity precision and spatial and temporal resolution requirements. A proof of concept Optical Autocovariance Wind Lidar (OAWL) has been demonstrated, and a robust multi- wavelength, field-widened (more than 100 microR) lidar system suitable for high altitude (over 16km) aircraft demonstration is under construction. Other advantages of the OAWL technique include insensitivity to aerosol/molecular backscatter mixing ratio, freedom from complex receiver/transmitter optical frequency lock loops, prospects for practical continuous large-area coverage wind profiling from GEO, and the availability of simultaneous multiple wavelength High Spectral Resolution Lidar (OA-HSRL) for aerosol identification and optical property measurements. We will discuss theory, development and demonstration status, advantages, limitations, and space-based performance of OAWL and OA-HSRL, as well as the potential for combined mission synergies.
NASA Technical Reports Server (NTRS)
Reale, Oreste; Lau, William K.; Kim, Kyu-Myong; Brin, Eugenia
2009-01-01
This article investigates the role of the Saharan air layer (SAL) in tropical cyclogenetic processes associated with a nondeveloping and a developing African easterly wave observed during the Special Observation Period (SOP-3) phase of the 2006 NASA African. Monsoon Multidisciplinary Analyses (NAMMA). The two waves are chosen because they both interact heavily with Saharan air. A glottal data assimilation and forecast system, the NASA Goddard Earth Observing System. version 5 (GEOS-5), is being run to produce a set of high-9 uality global analyses, inclusive of all observations used operationally but with additional satellite information. In particular, following previous works by the same authors, the duality-controlled data from the Atmospheric Infrared Sounder (AIRS) used to produce these analyses have a better coverage than the one adopted by operational centers. From these improved analyses, two sets of 31 five-day high-resolution forecasts, at horizontal resolutions of both half and quarter degrees, are produced. Results indicate that very steep moisture gradients are associated with the SAL in forecasts and analyses, even at great distances from their source over the Sahara. In addition, a thermal dipole in the vertiieat (warm above, cool below) is present in the nondeveloping case. The Moderate Resolution Imaging Spoctroradiometer (MODIS) aboard NASA's Terra and Aqua satellites shows that aerosol optical thickness, indicative of more dust as opposed to other factors, is higher in the nondeveloping case. Altogether, results suggest that the radiative effect of dust may play some role in producing a thermal structure less favorable to cyclogenesis. Results also indicate that only global horizontal resolutions on the order of 20-30 km can capture the large-scale transport and the tine thermal structure of the SAL, inclusive of the sharp moisture gradients, reproducing the effect of tropical cyclone suppression that has been hypothesized by previous authors from observational and regional modeling perspectives. Thcse effects cannot be fully represented at lower resolutions, therefore global resolution of a quarter of a degree is a minimum critical threshold necessary to investigate Atlantic tropical cyclogenesis from a global modeling perspective
High-Resolution Thermal Inertia Mapping from the Mars Global Surveyor Thermal Emission Spectrometer
Mellon, M.T.; Jakosky, B.M.; Kieffer, H.H.; Christensen, P.R.
2000-01-01
High-resolution thermal inertia mapping results are presented, derived from Mars Global Surveyor (MGS) Thermal Emission Spectrometer (TES) observations of the surface temperature of Mars obtained during the early portion of the MGS mapping mission. Thermal inertia is the key property controlling the diurnal surface temperature variations, and is dependent on the physical character of the top few centimeters of the surface. It represents a complex combination of particle size, rock abundance, exposures of bedrock, and degree of induration. In this work we describe the derivation of thermal inertia from TES data, present global scale analysis, and place these results into context with earlier work. A global map of nighttime thermal-bolometer-based thermal inertia is presented at 14?? per pixel resolution, with approximately 63% coverage between 50??S and 70??N latitude. Global analysis shows a similar pattern of high and low thermal inertia as seen in previous Viking low-resolution mapping. Significantly more detail is present in the high-resolution TES thermal inertia. This detail represents horizontal small-scale variability in the nature of the surface. Correlation with albedo indicates the presence of a previously undiscovered surface unit of moderate-to-high thermal inertia and intermediate albedo. This new unit has a modal peak thermal inertia of 180-250 J m-2 K-1 s-12 and a narrow range of albedo near 0.24. The unit, covering a significant fraction of the surface, typically surrounds the low thermal inertia regions and may comprise a deposit of indurated fine material. Local 3-km-resolution maps are also presented as examples of eolian, fluvial, and volcanic geology. Some impact crater rims and intracrater dunes show higher thermal inertias than the surrounding terrain; thermal inertia of aeolian deposits such as intracrater dunes may be related to average particle size. Outflow channels and valleys consistently show higher thermal inertias than the surrounding terrain. Generally, correlations between spatial variations in thermal inertia and geologic features suggest a relationship between the hundred-meter-scale morphology and the centimeter-scale surface layer. ?? 2000 Academic Press.
NASA Technical Reports Server (NTRS)
Hlavka, Dennis L.; Palm, S. P.; Welton, E. J.; Hart, W. D.; Spinhirne, J. D.; McGill, M.; Mahesh, A.; Starr, David OC. (Technical Monitor)
2001-01-01
The Geoscience Laser Altimeter System (GLAS) is scheduled for launch on the ICESat satellite as part of the NASA EOS mission in 2002. GLAS will be used to perform high resolution surface altimetry and will also provide a continuously operating atmospheric lidar to profile clouds, aerosols, and the planetary boundary layer with horizontal and vertical resolution of 175 and 76.8 m, respectively. GLAS is the first active satellite atmospheric profiler to provide global coverage. Data products include direct measurements of the heights of aerosol and cloud layers, and the optical depth of transmissive layers. In this poster we provide an overview of the GLAS atmospheric data products, present a simulated GLAS data set, and show results from the simulated data set using the GLAS data processing algorithm. Optical results from the ER-2 Cloud Physics Lidar (CPL), which uses many of the same processing algorithms as GLAS, show algorithm performance with real atmospheric conditions during the Southern African Regional Science Initiative (SAFARI 2000).
Magellan radar to reveal secrets of enshrouded Venus
NASA Technical Reports Server (NTRS)
Saunders, R. Stephen
1990-01-01
Imaging Venus with a synthetic aperture radar (SAR) with 70 percent global coverage at 1-km optical line-pair resolution to provide a detailed global characterization of the volcanic land-forms on Venus by an integration of image data with altimetry is discussed. The Magellan radar system uses navigation predictions to preset the radar data collection parameters. The data are collected in such a way as to preserve the Doppler signature of surface elements and later they are transmitted to the earth for processing into high-resolution radar images. To maintain high accuracy, a complex on-board filter algorithm allows the altitude control logic to respond only to a narrow range of expected photon intensity levels and only to signals that occur within a small predicted interval of time. Each mapping pass images a swath of the planet that varies in width from 20 to 25 km. Since the orbital plane of the spacecraft remains fixed in the inertial space, the slow rotation of Venus continually brings new areas into view of the spacecraft.
SweepSAR Sensor Technology for Dense Spatial and Temporal Coverage of Earth Change
NASA Astrophysics Data System (ADS)
Rosen, P. A.
2016-12-01
Since the 2007 National Academy of Science "Decadal Survey" report, NASA has been studying concepts for a Synthetic Aperture Radar (SAR) mission to determine Earth change in three disciplines - ecosystems, solid earth, and cryospheric sciences. NASA has joined forces with the Indian Space Research Organisation (ISRO) to fulfill these objectives. The NASA-ISRO SAR (NISAR) mission is now in development for a launch in 2021. The mission's primary science objectives are codified in a set of science requirements to study Earth land and ice deformation, and ecosystems, globally with 12-day sampling over all land and ice-covered surfaces throughout the mission life. The US and Indian science teams share global science objectives; in addition, India has developed a set of local objectives in agricultural biomass estimation, Himalayan glacier characterization, and coastal ocean measurements in and around India. Both the US and India have identified agricultural and infrastructure monitoring, and disaster response as high priority applications for the mission. With this range of science and applications objectives, NISAR has demanding coverage, sampling, and accuracy requirements. The system requires a swath of over 240 km at 3-10 m SAR imaging resolution, using full polarimetry where needed. Given the broad range of phenomena and wide range of sensitivities needed, NISAR carries two radars, one operating at L-band (24 cm wavelength) and the other at S-band (10 cm wavelength). The system uses a new "scan-on-receive" ("SweepSAR") technology at both L-band and S-band, that enables full swath coverage without loss of resolution or polarimetric diversity. Both radars can operate simultaneously. The L-band system is being designed to operate up to 50 minutes per orbit, and the S-band system up to 10 minutes per orbit. The orbit will be controlled to within 300 m for repeat-pass interferometry measurements. This unprecedented coverage in space, time, polarimetry, and frequency, will add a new and rich data set to the international constellation of sensors studying Earth surface change. In this talk, we will describe the mission's expected contributions to geodetic imaging in support of time-series analysis of dynamic changes of Earth's surface.
MISR 17.6 KM Gridded Cloud Motion Vectors: Overview and Assessment
NASA Technical Reports Server (NTRS)
Mueller, Kevin; Garay, Michael; Moroney, Catherine; Jovanovic, Veljko
2012-01-01
The MISR (Multi-angle Imaging SpectroRadiometer) instrument on the Terra satellite has been retrieving cloud motion vectors (CMVs) globally and almost continuously since early in 2000. In February 2012 the new MISR Level 2 Cloud product was publicly released, providing cloud motion vectors at 17.6 km resolution with improved accuracy and roughly threefold increased coverage relative to the 70.4 km resolution vectors of the current MISR Level 2 Stereo product (which remains available). MISR retrieves both horizontal cloud motion and height from the apparent displacement due to parallax and movement of cloud features across three visible channel (670nm) camera views over a span of 200 seconds. The retrieval has comparable accuracy to operational atmospheric motion vectors from other current sensors, but holds the additional advantage of global coverage and finer precision height retrieval that is insensitive to radiometric calibration. The MISR mission is expected to continue operation for many more years, possibly until 2019, and Level 2 Cloud has the possibility of being produced with a sensing-to-availability lag of 5 hours. This report compares MISR CMV with collocated motion vectors from arctic rawinsonde sites, and from the GOES and MODISTerra instruments. CMV at heights below 3 km exhibit the smallest differences, as small as 3.3 m/s for MISR and GOES. Clouds above 3 km exhibit larger differences, as large as 8.9 m/s for MISR and MODIS. Typical differences are on the order of 6 m/s.
Constellation Coverage Analysis
NASA Technical Reports Server (NTRS)
Lo, Martin W. (Compiler)
1997-01-01
The design of satellite constellations requires an understanding of the dynamic global coverage provided by the constellations. Even for a small constellation with a simple circular orbit propagator, the combinatorial nature of the analysis frequently renders the problem intractable. Particularly for the initial design phase where the orbital parameters are still fluid and undetermined, the coverage information is crucial to evaluate the performance of the constellation design. We have developed a fast and simple algorithm for determining the global constellation coverage dynamically using image processing techniques. This approach provides a fast, powerful and simple method for the analysis of global constellation coverage.
Enhancing Spatial Resolution of Remotely Sensed Imagery Using Deep Learning
NASA Astrophysics Data System (ADS)
Beck, J. M.; Bridges, S.; Collins, C.; Rushing, J.; Graves, S. J.
2017-12-01
Researchers at the Information Technology and Systems Center at the University of Alabama in Huntsville are using Deep Learning with Convolutional Neural Networks (CNNs) to develop a method for enhancing the spatial resolutions of moderate resolution (10-60m) multispectral satellite imagery. This enhancement will effectively match the resolutions of imagery from multiple sensors to provide increased global temporal-spatial coverage for a variety of Earth science products. Our research is centered on using Deep Learning for automatically generating transformations for increasing the spatial resolution of remotely sensed images with different spatial, spectral, and temporal resolutions. One of the most important steps in using images from multiple sensors is to transform the different image layers into the same spatial resolution, preferably the highest spatial resolution, without compromising the spectral information. Recent advances in Deep Learning have shown that CNNs can be used to effectively and efficiently upscale or enhance the spatial resolution of multispectral images with the use of an auxiliary data source such as a high spatial resolution panchromatic image. In contrast, we are using both the spatial and spectral details inherent in low spatial resolution multispectral images for image enhancement without the use of a panchromatic image. This presentation will discuss how this technology will benefit many Earth Science applications that use remotely sensed images with moderate spatial resolutions.
Mapping Impervious Surfaces Globally at 30m Resolution Using Global Land Survey Data
NASA Technical Reports Server (NTRS)
DeColstoun, Eric Brown; Huang, Chengquan; Tan, Bin; Smith, Sarah Elizabeth; Phillips, Jacqueline; Wang, Panshi; Ling, Pui-Yu; Zhan, James; Li, Sike; Taylor, Michael P.;
2013-01-01
Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (approx. 2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified archive of the National Geospatial Intelligence Agency (NGA). For each continental area several million training pixels are derived by analysts using image segmentation algorithms and tools and then aggregated to the 30m resolution of Landsat. Here we will discuss the production/testing of this massive data set for Europe, North and South America and Africa, including assessments of the 2010 surface reflectance data. This type of analysis is only possible because of the availability of long term 30m data sets from GLS and shows much promise for integration of Landsat 8 data in the future.
Mapping Impervious Surfaces Globally at 30m Resolution Using Landsat Global Land Survey Data
NASA Astrophysics Data System (ADS)
Brown de Colstoun, E.; Huang, C.; Wolfe, R. E.; Tan, B.; Tilton, J.; Smith, S.; Phillips, J.; Wang, P.; Ling, P.; Zhan, J.; Xu, X.; Taylor, M. P.
2013-12-01
Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (~2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified archive of the National Geospatial Intelligence Agency (NGA). For each continental area several million training pixels are derived by analysts using image segmentation algorithms and tools and then aggregated to the 30m resolution of Landsat. Here we will discuss the production/testing of this massive data set for Europe, North and South America and Africa, including assessments of the 2010 surface reflectance data. This type of analysis is only possible because of the availability of long term 30m data sets from GLS and shows much promise for integration of Landsat 8 data in the future.
High-Resolution Satellite Data Open for Government Research
NASA Technical Reports Server (NTRS)
Neigh, Christopher S. R.; Masek, Jeffrey G.; Nickeson, Jaime E.
2013-01-01
U.S. satellite commercial imagery (CI) with resolution less than 1 meter is a common geospatial reference used by the public through Web applications, mobile devices, and the news media. However, CI use in the scientific community has not kept pace, even though those who are performing U.S. government research have access to these data at no cost.Previously, studies using multiple CI acquisitions from IKONOS-2, Quickbird-2, GeoEye-1, WorldView-1, and WorldView-2 would have been cost prohibitive. Now, with near-global submeter coverage and online distribution, opportunities abound for future scientific studies. This archive is already quite extensive (examples are shown in Figure 1) and is being used in many novel applications.
Global Earth Outgoing Radiation From A Constellation Of Satellites: Proof-Of-Concept Study
NASA Astrophysics Data System (ADS)
Gristey, J. J.; Chiu, J. Y. C.; Gurney, R. J.; Han, S. C.; Morcrette, C. J.
2017-12-01
The flux of radiation exiting at the top of the atmosphere, referred to as Earth Outgoing Radiation (EOR), constitutes a vital component of the Earth's energy budget. Since EOR is inherently connected to the rapidly evolving scene from which the radiation originates and exhibits large regional variations, it is of paramount importance that we can monitor EOR at a sufficient frequency and spatial scale for weather and climate studies. Achieving these criteria remains challenging using traditional measurement techniques. However, explosive development in small satellite technology and sensor miniaturisation has paved a viable route for measurements to be made from a constellation of satellites in different orbits. This offers an exciting new opportunity to make observations of EOR with both global coverage and high temporal resolution for the first time. To assess the potential of the constellation approach for observing EOR we perform a series of observing system simulation experiments. We will outline a baseline constellation configuration capable of sampling the Earth with unprecedented temporal resolution. Using this configuration and a sophisticated deconvolution technique, we demonstrate how to recover synoptic-scale global EOR to the accuracy required to understand Earth's global energy budget. Finally, we will reveal the impact of various modifications to the constellation configuration and provide recommendations for the community.
Validation of the Version 1 NOAA/NASA Pathfinder Sea Surface Temperature Data Set
NASA Technical Reports Server (NTRS)
Smith, Elizabeth A.
1998-01-01
A high-resolution, global satellite-derived sea surface temperature (SST) data set called Pathfinder, from the Advanced Very High Resolution Radiometer (AVHRR) aboard the NOAA Polar Orbiters, is available from the Jet Propulsion Laboratory Physical Oceanography Distributed Active Archive Center (JPL PO.DAAC). Suitable for research as well as education, the Pathfinder SST data set is a result of a collaboration between the National Oceanographic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA) and investigators at several universities. NOAA and NASA are the sponsors of the Pathfinder Program, which takes advantage of currently archived Earth science data from satellites. Where necessary, satellite sensors have been intercalibrated, algorithms improved and processing procedures revised, in order to produce long time-series, global measurements of ocean, land and atmospheric properties necessary for climate research. Many Pathfinder data sets are available to researchers now, nearly a decade before the first launch of NASA's Earth Observing System (EOS). The lessons learned from the Pathfinder programs will facilitate the processing and management of terabytes of data from EOS. The Oceans component of Pathfinder has undertaken to reprocess all Global Area Coverage (GAC) data acquired by the 5-channel AVHRRs since 1981. The resultant data products are consistent and stably calibrated [Rao, 1993a, Rao, 1993b, Brown et al., 1993], Earth-gridded SST fields at a variety of spatial and temporal resolutions.
Global safe anaesthesia and surgery initiatives: implications for anaesthesia in the Pacific region.
Cooper, M G; Wake, P B; Morriss, W W; Cargill, P D; McDougall, R J
2016-05-01
In 2015 three major events occurred for global anaesthesia and surgery. In January, the World Bank published Disease Control Priorities 3rd edition (DCP 3rd edition). This volume, Essential Surgery, highlighted the cost effective role of anaesthesia and surgery in global health. In April, the Lancet Commission on Global Surgery released its report "Global Surgery 2030: Evidence and solutions for achieving health, welfare, and economic development". The report focuses on five key areas to promote change including: access to timely surgery, surgical workforce and procedural capability, surgical volume, data collection such as perioperative mortality rate, and financial protection. In May, the 68th World Health Assembly (WHA) voted in favour of Resolution A68/31: Strengthening emergency and essential surgical and anaesthesia care as a component of universal health coverage. The resolution was passed unanimously and it is the first time that surgery and anaesthesia have received such prominence at WHA level. These three events all have profound implications for the provision and access of safe anaesthesia and surgery in the Pacific region in the next 15 years. This article considers some of the regional factors that affect these five key areas, especially with regard to anaesthetic specialist workforce density in different parts of the region. There are many challenges to improve anaesthesia access, safety, and workforce density in the Pacific region. Future efforts, initiatives and support will help address these problems.
Sensor Webs: Autonomous Rapid Response to Monitor Transient Science Events
NASA Technical Reports Server (NTRS)
Mandl, Dan; Grosvenor, Sandra; Frye, Stu; Sherwood, Robert; Chien, Steve; Davies, Ashley; Cichy, Ben; Ingram, Mary Ann; Langley, John; Miranda, Felix
2005-01-01
To better understand how physical phenomena, such as volcanic eruptions, evolve over time, multiple sensor observations over the duration of the event are required. Using sensor web approaches that integrate original detections by in-situ sensors and global-coverage, lower-resolution, on-orbit assets with automated rapid response observations from high resolution sensors, more observations of significant events can be made with increased temporal, spatial, and spectral resolution. This paper describes experiments using Earth Observing 1 (EO-1) along with other space and ground assets to implement progressive mission autonomy to identify, locate and image with high resolution instruments phenomena such as wildfires, volcanoes, floods and ice breakup. The software that plans, schedules and controls the various satellite assets are used to form ad hoc constellations which enable collaborative autonomous image collections triggered by transient phenomena. This software is both flight and ground based and works in concert to run all of the required assets cohesively and includes software that is model-based, artificial intelligence software.
A GLOBAL GEOLOGIC MAP OF GANYMEDE
NASA Astrophysics Data System (ADS)
Patterson, G.; Collins, G. C.; Head, J. W.; Pappalardo, R. T.; Prockter, L. M.; Lucchitta, B. K.
2009-12-01
Ganymede is a planet-sized world, the solar system’s largest satellite with a radius of 2631 km. Its physiography, geology, geophysics, surface composition, and evolution are correspondingly planet-like in intricacy. We have completed a global geological map of Ganymede that represents the most recent understanding of the satellite on the basis of Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. Material units have been defined, structural landforms have been identified, and an approximate stratigraphy has been determined utilizing a global mosaic of the surface with a nominal resolution of 1 km/pixel assembled by the USGS. This mosaic incorporates the best available Voyager and Galileo regional coverage and high resolution imagery (100-200 m/pixel) of characteristic features and terrain types obtained by the Galileo spacecraft. This effort has provided a more complete understanding of: 1) the major geological processes operating on Ganymede, 2) the characteristics of the geological units making up its surface, 3) the stratigraphic relationships of geological units and structures, and 4) the geological history inferred from these relationships.
Small Spacecraft Constellation Concept for Mars Atmospheric Radio Occultations
NASA Astrophysics Data System (ADS)
Asmar, S. W.; Mannucci, A. J.; Ao, C. O.; Kobayashi, M. M.; Lazio, J.; Marinan, A.; Massone, G.; McCandless, S. E.; Preston, R. A.; Seubert, J.; Williamson, W.
2017-12-01
First demonstrated in 1965 when Mariner IV flew by Mars and determined the salient features of its atmosphere, radio occultation experiments have been carried out on numerous planetary missions with great discoveries. These experiments utilize the now classic configuration of a signal from a single planetary spacecraft to Earth receiving stations, where the science data are acquired. The Earth science community advanced the technique to utilizing a constellation of spacecraft with the radio occultation links between the spacecraft, enabled by the infrastructure of the Global Positioning System. With the advent of small and less costly spacecraft, such as planetary CubeSats and other variations, such as the anticipated innovative Mars Cube One mission, crosslinks among small spacecraft can be used to study other planets in the near future. Advantages of this type of experiment include significantly greater geographical coverage, which could reach global coverage over a few weeks with a small number of spacecraft. Repeatability of the global coverage can lead to examining temperature-pressure profiles and ionospheric electron density profiles, on daily, seasonal, annual, or other time scales of interest. The higher signal-to-noise ratio for inter-satellite links, compared to a link to Earth, decreases the design demands on the instrumentation (smaller antennas and transmitters, etc.). After an actual Mars crosslink demonstration, this concept has been in development using Mars as a possible target. Scientific objectives, delivery methods, operational scenarios and end-to-end configuration have been documented. Science objectives include determining the state and variability of the lower Martian atmosphere, which has been an identified as a high priority objective by the Mars Exploration Program Analysis Group, particularly as it relates to entry, descent, and landing and ascent for future crewed and robotic missions. This paper will present the latest research on the proposed mission concept including the possible spatial and temporal coverage, resolution of observables, mission design and expected results.
Application of Spaceborne Scatterometer to Study Typhoon, Tropical Hydrologic Balance and El Nino
NASA Technical Reports Server (NTRS)
Liu, W. Timothy
1995-01-01
The high spatial resolution and global coverage of a spaceborne microwave scatterometer make it a power instrument to study phenomena ranging from typhoon to El Nino Southern Oscillation which have regional and short term economic and ecological impacts as well as effects on long term and global climate changes. In this report, the application of scatterometer data, by itself, to study the intensity and the evolution of typhoon is demonstrated. The potential of combining wind vector and precipitable water derived from two spaceborne sensors to study the hydrologic balance in the tropics is discussed. The role of westerly wind bursts as a precursor of anomalous warming in the equatorial Pacific is investigated with coincident data from microwave scatterometer, altimeter and radiometer.
Report of the panel on the land surface: Process of change, section 5
NASA Technical Reports Server (NTRS)
Adams, John B.; Barron, Eric E.; Bloom, Arthur A.; Breed, Carol; Dohrenwend, J.; Evans, Diane L.; Farr, Thomas T.; Gillespie, Allan R.; Isaks, B. L.; Williams, Richard S.
1991-01-01
The panel defined three main areas of study that are central to the Solid Earth Science (SES) program: climate interactions with the Earth's surface, tectonism as it affects the Earth's surface and climate, and human activities that modify the Earth's surface. Four foci of research are envisioned: process studies with an emphasis on modern processes in transitional areas; integrated studies with an emphasis on long term continental climate change; climate-tectonic interactions; and studies of human activities that modify the Earth's surface, with an emphasis on soil degradation. The panel concluded that there is a clear requirement for global coverage by high resolution stereoscopic images and a pressing need for global topographic data in support of studies of the land surface.
Impact of geostationary satellite water vapor channel data on weather analysis and forecasting
NASA Technical Reports Server (NTRS)
Velden, Christopher S.
1995-01-01
Preliminary results from NWP impact studies are indicating that upper-tropospheric wind information provided by tracking motions in sequences of geostationary satellite water vapor imagery can positively influence forecasts on regional scales, and possibly on global scales as well. The data are complimentary to cloud-tracked winds by providing data in cloud-free regions, as well as comparable in quality. First results from GOES-8 winds are encouraging, and further efforts and model impacts will be directed towards optimizing these data in numerical weather prediction (NWP). Assuming successful launches of GOES-J and GMS-5 satellites in 1995, high quality and resolution water vapor imagers will be available to provide nearly complete global upper-tropospheric wind coverage.
2015-01-31
VANDENBERG AIR FORCE BASE, Calif. – An exhaust cloud builds around the United Launch Alliance Delta II rocket as it lifts off Space Launch Complex 2 at Vandenberg Air Force Base, carrying NASA's Soil Moisture Active Passive satellite, or SMAP, on a mission to study global coverage of soil moisture and freeze/thaw measurements. Launch was at 9:22 a.m. EST. SMAP is designed to produce the highest-resolution maps of soil moisture ever obtained from space. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett
Initial Validation of NDVI time seriesfrom AVHRR, VEGETATION, and MODIS
NASA Technical Reports Server (NTRS)
Morisette, Jeffrey T.; Pinzon, Jorge E.; Brown, Molly E.; Tucker, Jim; Justice, Christopher O.
2004-01-01
The paper will address Theme 7: Multi-sensor opportunities for VEGETATION. We present analysis of a long-term vegetation record derived from three moderate resolution sensors: AVHRR, VEGETATION, and MODIS. While empirically based manipulation can ensure agreement between the three data sets, there is a need to validate the series. This paper uses atmospherically corrected ETM+ data available over the EOS Land Validation Core Sites as an independent data set with which to compare the time series. We use ETM+ data from 15 globally distributed sites, 7 of which contain repeat coverage in time. These high-resolution data are compared to the values of each sensor by spatially aggregating the ETM+ to each specific sensors' spatial coverage. The aggregated ETM+ value provides a point estimate for a specific site on a specific date. The standard deviation of that point estimate is used to construct a confidence interval for that point estimate. The values from each moderate resolution sensor are then evaluated with respect to that confident interval. Result show that AVHRR, VEGETATION, and MODIS data can be combined to assess temporal uncertainties and address data continuity issues and that the atmospherically corrected ETM+ data provide an independent source with which to compare that record. The final product is a consistent time series climate record that links historical observations to current and future measurements.
NASA Astrophysics Data System (ADS)
A, Duo; Zhao, Wenji; Qu, Xinyuan; Jing, Ran; Xiong, Kai
2016-12-01
Global climate change has led to significant vegetation changes in the past half century. North China Plain, the most important grain production base of china, is undergoing a process of prominent warming and drying. The vegetation coverage, which is used to monitor vegetation change, can respond to climate change (temperature and precipitation). In this study, GIMMS (Global Inventory Modelling and Mapping Studies)-NDVI (Normalized Difference Vegetation Index) data, MODIS (Moderate-resolution Imaging Spectroradiometer) - NDVI data and climate data, during 1981-2013, were used to investigate the spatial distribution and changes of vegetation. The relationship between climate and vegetation on different spatial (agriculture, forest and grassland) and temporal (yearly, decadal and monthly) scales were also analyzed in North China Plain. (1) It was found that temperature exhibiting a slight increase trend (0.20 °C/10a, P < 0.01). This may be due to the disappearance of 0 °C isotherm, the rise of spring temperature. At the same time, precipitation showed a significant reduction trend (-1.75 mm/10a, P > 0.05). The climate mutation period was during 1991-1994. (2) Vegetation coverage slight increase was observed in the 55% of total study area, with a change rate of 0.00039/10a. Human activities may not only accelerate the changes of the vegetation coverage, but also c effect to the rate of these changes. (3) Overall, the correlation between the vegetation coverage and climatic factor is higher in monthly scale than yearly scale. The correlation analysis between vegetation coverage and climate changes showed that annual vegetation coverage was better correlatend with precipitation in grassland biome; but it showed a better correlated with temperature i the agriculture biome and forest biome. In addition, the vegetation coverage had sensitive time-effect respond to precipitation. (4) The vegetation coverage showed the same increasing trend before and after the climatic variations, but the rate of increase slowed down. From the vegetation coverage point of view, the grassland ecological zone had an obvious response to the climatic variations, but the agricultural ecological zones showed a significant response from the vegetation coverage change rate point of view. The effect of human activity in degradation region was higher than that in improvement area. But after the climate abruptly changing, the effect of human activity in improvement area was higher than that in degradation region, and the influence of human activity will continue in the future.
Evaluation of registration accuracy between Sentinel-2 and Landsat 8
NASA Astrophysics Data System (ADS)
Barazzetti, Luigi; Cuca, Branka; Previtali, Mattia
2016-08-01
Starting from June 2015, Sentinel-2A is delivering high resolution optical images (ground resolution up to 10 meters) to provide a global coverage of the Earth's land surface every 10 days. The planned launch of Sentinel-2B along with the integration of Landsat images will provide time series with an unprecedented revisit time indispensable for numerous monitoring applications, in which high resolution multi-temporal information is required. They include agriculture, water bodies, natural hazards to name a few. However, the combined use of multi-temporal images requires an accurate geometric registration, i.e. pixel-to-pixel correspondence for terrain-corrected products. This paper presents an analysis of spatial co-registration accuracy for several datasets of Sentinel-2 and Landsat 8 images distributed all around the world. Images were compared with digital correlation techniques for image matching, obtaining an evaluation of registration accuracy with an affine transformation as geometrical model. Results demonstrate that sub-pixel accuracy was achieved between 10 m resolution Sentinel-2 bands (band 3) and 15 m resolution panchromatic Landsat images (band 8).
NASA Technical Reports Server (NTRS)
Steffen, K.; Abdalati, W.; Stroeve, J.
1993-01-01
The feasibility of using satellite data for climate research over the Greenland ice sheet is discussed. In particular, we demonstrate the usefulness of Advanced Very High Resolution Radiometer (AVHRR) Local Area Coverage (LAC) and Global Area Coverage (GAC) data for narrow-band albedo retrieval. Our study supports the use of lower resolution AVHRR (GAC) data for process studies over most of the Greenland ice sheet. Based on LAC data time series analysis, we can resolve relative albedo changes on the order of 2-5%. In addition, we examine Scanning Multichannel Microwave Radiometer (SMMR) and Special Sensor Microwave Imager (SSM/I) passive microwave data for snow typing and other signals of climatological significance. Based on relationships between in situ measurements and horizontally polarized 19 and 37 GHz observations, wet snow regions are identified. The wet snow regions increase in aerial percentage from 9% of the total ice surface in June to a maximum of 26% in August 1990. Furthermore, the relationship between brightness temperatures and accumulation rates in the northeastern part of Greenland is described. We found a consistent increase in accumulation rate for the northeastern part of the ice sheet from 1981 to 1986.
NASA Astrophysics Data System (ADS)
Hengl, Tomislav; Heuvelink, Gerard; Sanderman, Jonathan; MacMillan, Robert
2017-04-01
There is an increasing interest in fitting and applying spatiotemporal models that can be used to assess and monitor soil organic carbon stocks (SOCS), for example, in support of the '4 pourmille' initiative aiming at soil carbon sequestration towards climate change adaptation and mitigation and UN's Land Degradation Neutrality indicators and similar degradation assessment projects at regional and global scales. The land cover mapping community has already produced several spatiotemporal data sets with global coverage and at relatively fine resolution e.g. USGS MODIS land cover annual maps for period 2000-2014; European Space Agency land cover maps at 300 m resolution for the year 2000, 2005 and 2010; Chinese GlobeLand30 dataset available for years 2000 and 2010; Columbia University's WRI GlobalForestWatch with deforestation maps at 30 m resolution for the period 2000-2016 (Hansen et al. 2013). These data sets can be used for land degradation assessment and scenario testing at global and regional scales (Wei et al 2014). Currently, however, no compatible global spatiotemporal data sets exist on status of soil quality and/or soil health (Powlson et al. 2013). This paper describes an initial effort to devise and evaluate a procedure for mapping spatio-temporal changes in SOC stocks using a complete stack of soil forming factors (climate, relief, land cover, land use, lithology and living organisms) represented mainly through remote sensing based time series of Earth images. For model building we used some 75,000 geo-referenced soil profiles and a stacks space-time covariates (land cover, land use, biomass, climate) at two standard resolutions: (1) 10 km resolution with data available for period 1920-2014 and (2) 1000 m resolution with data available for period 2000-2014. The initial results show that, although it is technically feasible to produce space time estimates of SOCS that demonstrate the procedure, the estimates are relatively uncertain (<45% of variation explained) and lead to obvious artifacts, especially in areas that have not be represented in time-dimension (temporal extrapolation). For some regions that possess somewhat adequate amounts of point data in space and time (e.g. USA) relatively credible space time estimates can be produced. By adding more training data (both legacy and newly collected points) these models can be gradually improved until they can become operational for decision making and scenario testing.
NASA Astrophysics Data System (ADS)
Antoine, David; André, Jean-Michel; Morel, André
A fast method has been proposed [Antoine and Morel, this issue] to compute the oceanic primary production from the upper ocean chlorophyll-like pigment concentration, as it can be routinely detected by a spaceborne ocean color sensor. This method is applied here to the monthly global maps of the photosynthetic pigments that were derived from the coastal zone color scanner (CZCS) data archive [Feldman et al., 1989]. The photosynthetically active radiation (PAR) field is computed from the astronomical constant and by using an atmospheric model, thereafter combined with averaged cloud information, derived from the International Satellite Cloud Climatology Project (ISCCP). The aim is to assess the seasonal evolution, as well as the spatial distribution of the photosynthetic carbon fixation within the world ocean and for a ``climatological year,'' to the extent that both the chlorophyll information and the cloud coverage statistics actually are averages obtained over several years. The computed global annual production actually ranges between 36.5 and 45.6 Gt C yr-1 according to the assumption which is made (0.8 or 1) about the ratio of active-to-total pigments (recall that chlorophyll and pheopigments are not radiometrically resolved by CZCS). The relative contributions to the global productivity of the various oceans and zonal belts are examined. By considering the hypotheses needed in such computations, the nature of the data used as inputs, and the results of the sensitivity studies, the global numbers have to be cautiously considered. Improving the reliability of the primary production estimates implies (1) new global data sets allowing a higher temporal resolution and a better coverage, (2) progress in the knowledge of physiological responses of phytoplankton and therefore refinements of the time and space dependent parameterizations of these responses.
Mars Digital Image Model 2.1 Control Network
NASA Technical Reports Server (NTRS)
Archinal, B. A.; Kirk, R. L.; Duxbury, T. C.; Lee, E. M.; Sucharski, R.; Cook, D.
2003-01-01
USGS is currently preparing a new version of its global Mars digital image mosaic, which will be known as MDIM 2.1. As part of this process we are completing a new photogrammetric solution of the global Mars control network. This is an improved version of the network established earlier by RAND and USGS personnel, as partially described previously. MDIM 2.1 will have many improvements over earlier Viking Orbiter (VO) global mosaics. Geometrically, it will be an orthoimage product, draped on Mars Orbiter Laser Altimeter (MOLA) derived topography, thus accounting properly for the commonly oblique VO imagery. Through the network being described here it will be tied to the newly defined IAU/IAG 2000 Mars coordinate system via ties to MOLA data. Thus, MDIM 2.1 will provide complete global orthorectified imagery coverage of Mars at the resolution of 1/256 deg of MDIM 2.0, and be compatible with MOLA and other products produced in the current coordinate system.
NASA Astrophysics Data System (ADS)
Malanotte-Rizzoli, Paola; Young, Roberta E.
1995-12-01
The primary objective of this paper is to assess the relative effectiveness of data sets with different space coverage and time resolution when they are assimilated into an ocean circulation model. We focus on obtaining realistic numerical simulations of the Gulf Stream system typically of the order of 3-month duration by constructing a "synthetic" ocean simultaneously consistent with the model dynamics and the observations. The model used is the Semispectral Primitive Equation Model. The data sets are the "global" Optimal Thermal Interpolation Scheme (OTIS) 3 of the Fleet Numerical Oceanography Center providing temperature and salinity fields with global coverage and with bi-weekly frequency, and the localized measurements, mostly of current velocities, from the central and eastern array moorings of the Synoptic Ocean Prediction (SYNOP) program, with daily frequency but with a very small spatial coverage. We use a suboptimal assimilation technique ("nudging"). Even though this technique has already been used in idealized data assimilation studies, to our knowledge this is the first study in which the effectiveness of nudging is tested by assimilating real observations of the interior temperature and salinity fields. This is also the first work in which a systematic assimilation is carried out of the localized, high-quality SYNOP data sets in numerical experiments longer than 1-2 weeks, that is, not aimed to forecasting. We assimilate (1) the global OTIS 3 alone, (2) the local SYNOP observations alone, and (3) both OTIS 3 and SYNOP observations. We assess the success of the assimilations with quantitative measures of performance, both on the global and local scale. The results can be summarized as follows. The intermittent assimilation of the global OTIS 3 is necessary to keep the model "on track" over 3-month simulations on the global scale. As OTIS 3 is assimilated at every model grid point, a "gentle" weight must be prescribed to it so as not to overconstrain the model. However, in these assimilations the predicted velocity fields over the SYNOP arrays are greatly in error. The continuous assimilation of the localized SYNOP data sets with a strong weight is necessary to obtain local realistic evolutions. Then assimilation of velocity measurements alone recovers the density structure over the array area. However, the spatial coverage of the SYNOP measurements is too small to constrain the model on the global scale. Thus the blending of both types of datasets is necessary in the assimilation as they constrain different time and space scales. Our choice of "gentle" nudging weight for the global OTIS 3 and "strong" weight for the local SYNOP data provides for realistic simulations of the Gulf Stream system, both globally and locally, on the 3- to 4-month-long timescale, the one governed by the Gulf Stream jet internal dynamics.
Downscaling global precipitation for local applications - a case for the Rhine basin
NASA Astrophysics Data System (ADS)
Sperna Weiland, Frederiek; van Verseveld, Willem; Schellekens, Jaap
2017-04-01
Within the EU FP7 project eartH2Observe a global Water Resources Re-analysis (WRR) is being developed. This re-analysis consists of meteorological and hydrological water balance variables with global coverage, spanning the period 1979-2014 at 0.25 degrees resolution (Schellekens et al., 2016). The dataset can be of special interest in regions with limited in-situ data availability, yet for local scale analysis particularly in mountainous regions, a resolution of 0.25 degrees may be too coarse and downscaling the data to a higher resolution may be required. A downscaling toolbox has been made that includes spatial downscaling of precipitation based on the global WorldClim dataset that is available at 1 km resolution as a monthly climatology (Hijmans et al., 2005). The input of the down-scaling tool are either the global eartH2Observe WRR1 and WRR2 datasets based on the WFDEI correction methodology (Weedon et al., 2014) or the global Multi-Source Weighted-Ensemble Precipitation (MSWEP) dataset (Beck et al., 2016). Here we present a validation of the datasets over the Rhine catchment by means of a distributed hydrological model (wflow, Schellekens et al., 2014) using a number of precipitation scenarios. (1) We start by running the model using the local reference dataset derived by spatial interpolation of gauge observations. Furthermore we use (2) the MSWEP dataset at the native 0.25-degree resolution followed by (3) MSWEP downscaled with the WorldClim dataset and final (4) MSWEP downscaled with the local reference dataset. The validation will be based on comparison of the modeled river discharges as well as rainfall statistics. We expect that down-scaling the MSWEP dataset with the WorldClim data to higher resolution will increase its performance. To test the performance of the down-scaling routine we have added a run with MSWEP data down-scaled with the local dataset and compare this with the run based on the local dataset itself. - Beck, H. E. et al., 2016. MSWEP: 3-hourly 0.25° global gridded precipitation (1979-2015) by merging gauge, satellite, and reanalysis data, Hydrol. Earth Syst. Sci. Discuss., doi:10.5194/hess-2016-236, accepted for final publication. - Hijmans, R.J. et al., 2005. Very high resolution interpolated climate surfaces for global land areas. International Journal of Climatology 25: 1965-1978. - Schellekens, J. et al., 2016. A global water resources ensemble of hydrological models: the eartH2Observe Tier-1 dataset, Earth Syst. Sci. Data Discuss., doi:10.5194/essd-2016-55, under review. - Schellekens, J. et al., 2014. Rapid setup of hydrological and hydraulic models using OpenStreetMap and the SRTM derived digital elevation model. Environmental Modelling&Software - Weedon, G.P. et al., 2014. The WFDEI meteorological forcing data set: WATCH Forcing Data methodology applied to ERA-Interim reanalysis data. Water Resources Research, 50, doi:10.1002/2014WR015638.
Clark, Jocalyn
2014-01-01
Universal health coverage (UHC) has emerged as the leading and recommended overarching health goal on the post-2015 development agenda, and is promoted with fervour. UHC has the backing of major medical and health institutions, and is designed to provide patients with universal access to needed health services without financial hardship, but is also projected to have 'a transformative effect on poverty, hunger, and disease'. Multiple reports and resolutions support UHC and few offer critical analyses; but among these are concerns with imprecise definitions and the ability to implement UHC at the country level. A medicalization lens enriches these early critiques and identifies concerns that the UHC campaign contributes to the medicalization of global health. UHC conflates health with health care, thus assigning undue importance to (biomedical) health services and downgrading the social and structural determinants of health. There is poor evidence that UHC or health care alone improves population health outcomes, and in fact health care may worsen inequities. UHC is reductionistic because it focuses on preventative and curative actions delivered at the individual level, and ignores the social and political determinants of health and right to health that have been supported by decades of international work and commitments. UHC risks commodifying health care, which threatens the underlying principles of UHC of equity in access and of health care as a collective good.
Barrier Coverage for 3D Camera Sensor Networks
Wu, Chengdong; Zhang, Yunzhou; Jia, Zixi; Ji, Peng; Chu, Hao
2017-01-01
Barrier coverage, an important research area with respect to camera sensor networks, consists of a number of camera sensors to detect intruders that pass through the barrier area. Existing works on barrier coverage such as local face-view barrier coverage and full-view barrier coverage typically assume that each intruder is considered as a point. However, the crucial feature (e.g., size) of the intruder should be taken into account in the real-world applications. In this paper, we propose a realistic resolution criterion based on a three-dimensional (3D) sensing model of a camera sensor for capturing the intruder’s face. Based on the new resolution criterion, we study the barrier coverage of a feasible deployment strategy in camera sensor networks. Performance results demonstrate that our barrier coverage with more practical considerations is capable of providing a desirable surveillance level. Moreover, compared with local face-view barrier coverage and full-view barrier coverage, our barrier coverage is more reasonable and closer to reality. To the best of our knowledge, our work is the first to propose barrier coverage for 3D camera sensor networks. PMID:28771167
Barrier Coverage for 3D Camera Sensor Networks.
Si, Pengju; Wu, Chengdong; Zhang, Yunzhou; Jia, Zixi; Ji, Peng; Chu, Hao
2017-08-03
Barrier coverage, an important research area with respect to camera sensor networks, consists of a number of camera sensors to detect intruders that pass through the barrier area. Existing works on barrier coverage such as local face-view barrier coverage and full-view barrier coverage typically assume that each intruder is considered as a point. However, the crucial feature (e.g., size) of the intruder should be taken into account in the real-world applications. In this paper, we propose a realistic resolution criterion based on a three-dimensional (3D) sensing model of a camera sensor for capturing the intruder's face. Based on the new resolution criterion, we study the barrier coverage of a feasible deployment strategy in camera sensor networks. Performance results demonstrate that our barrier coverage with more practical considerations is capable of providing a desirable surveillance level. Moreover, compared with local face-view barrier coverage and full-view barrier coverage, our barrier coverage is more reasonable and closer to reality. To the best of our knowledge, our work is the first to propose barrier coverage for 3D camera sensor networks.
Verdin, Kristine L.; Godt, Jonathan W.; Funk, Christopher C.; Pedreros, Diego; Worstell, Bruce; Verdin, James
2007-01-01
Landslides resulting from earthquakes can cause widespread loss of life and damage to critical infrastructure. The U.S. Geological Survey (USGS) has developed an alarm system, PAGER (Prompt Assessment of Global Earthquakes for Response), that aims to provide timely information to emergency relief organizations on the impact of earthquakes. Landslides are responsible for many of the damaging effects following large earthquakes in mountainous regions, and thus data defining the topographic relief and slope are critical to the PAGER system. A new global topographic dataset was developed to aid in rapidly estimating landslide potential following large earthquakes. We used the remotely-sensed elevation data collected as part of the Shuttle Radar Topography Mission (SRTM) to generate a slope dataset with nearly global coverage. Slopes from the SRTM data, computed at 3-arc-second resolution, were summarized at 30-arc-second resolution, along with statistics developed to describe the distribution of slope within each 30-arc-second pixel. Because there are many small areas lacking SRTM data and the northern limit of the SRTM mission was lat 60?N., statistical methods referencing other elevation data were used to fill the voids within the dataset and to extrapolate the data north of 60?. The dataset will be used in the PAGER system to rapidly assess the susceptibility of areas to landsliding following large earthquakes.
Mapping of the Moon by Clementine
McEwen, A.S.; Robinson, M.S.
1997-01-01
The "faster, cheaper, better" Clementine spacecraft mission mapped the Moon from February 19 to May 3, 1994. Global coverage was acquired in 11 spectral bandpasses from 415 to 2792 nm and at resolutions of 80-330 m/pixel; a thermal-infrared camera sampled ???20% of the surface; a high-resolution camera sampled selected areas (especially the polar regions); and a lidar altimeter mapped the large-scale topography up to latitudes of ??75??. The spacecraft was in a polar, elliptical orbit, 400-450 km periselene altitude. Periselene latitude was -28.5?? for the first month of mapping, then moved to +28.5??. NASA is supporting the archiving, systematic processing, and analysis of the ???1.8 million lunar images and other datasets. A new global positional network has been constructed from 43,000 images and ???0.5 million match points; new digital maps will facilitate future lunar exploration. In-flight calibrations now enable photometry to a high level of precision for the uv-visible CCD camera. Early science results include: (1) global models of topography, gravity, and crustal thicknesses; (2) new information on the topography and structure of multiring impact basins; (3) evidence suggestive of water ice in large permanent shadows near the south pole; (4) global mapping of iron abundances; and (5) new constraints on the Phanerozoic cratering rate of the Earth. Many additional results are expected following completion of calibration and systematic processing efforts. ?? 1997 COSPAR. Published by Elsevier Science Ltd.
Evaluation of satellite-retrieved extreme precipitation using gauge observations
NASA Astrophysics Data System (ADS)
Lockhoff, M.; Zolina, O.; Simmer, C.; Schulz, J.
2012-04-01
Precipitation extremes have already been intensively studied employing rain gauge datasets. Their main advantage is that they represent a direct measurement with a relatively high temporal coverage. Their main limitation however is their poor spatial coverage and thus a low representativeness in many parts of the world. In contrast, satellites can provide global coverage and there are meanwhile data sets available that are on one hand long enough to be used for extreme value analysis and that have on the other hand the necessary spatial and temporal resolution to capture extremes. However, satellite observations provide only an indirect mean to determine precipitation and there are many potential observational and methodological weaknesses in particular over land surfaces that may constitute doubts concerning their usability for the analysis of precipitation extremes. By comparing basic climatological metrics of precipitation (totals, intensities, number of wet days) as well as respective characteristics of PDFs, absolute and relative extremes of satellite and observational data this paper aims at assessing to which extent satellite products are suitable for analysing extreme precipitation events. In a first step the assessment focuses on Europe taking into consideration various satellite products available, e.g. data sets provided by the Global Precipitation Climatology Project (GPCP). First results indicate that satellite-based estimates do not only represent the monthly averaged precipitation very similar to rain gauge estimates but they also capture the day-to-day occurrence fairly well. Larger differences can be found though when looking at the corresponding intensities.
TES/Aura L3 Atmospheric Temperatures Daily V5 (TL3ATD)
Atmospheric Science Data Center
2018-05-08
... Platform: TES Aura L1B Nadir/Limb Spatial Coverage: (-180, 180)(-90, 90) Spatial Resolution: 0.5 x 5 km nadir 2.3 x 23 km limb Temporal Coverage: 07/15/2004 - Present Temporal Resolution: ...
A New High Resolution Tidal Model in the Arctic Ocean
NASA Astrophysics Data System (ADS)
Cancet, M.; Andersen, O.; Lyard, F.; Schulz, A.; Cotton, D.; Benveniste, J.
2016-08-01
The Arctic Ocean is a challenging region for tidal modelling. The accuracy of the global tidal models decreases by several centimeters in the Polar Regions, which has a large impact on the quality of the satellite altimeter sea surface heights and the altimetry-derived products.NOVELTIS and DTU Space have developed a regional, high-resolution tidal atlas in the Arctic Ocean, in the framework of an extension of the CryoSat Plus for Ocean (CP4O) ESA STSE (Support to Science Element) project. In particular, this atlas benefits from the assimilation of the most complete satellite altimetry dataset ever used in this region, including Envisat data up to 82°N and CryoSat-2 data between 82°N and 88°N. The combination of these satellite altimetry missions gives the best possible coverage of altimetry-derived tidal constituents. The available tide gauge data were also used for data assimilation and validation.This paper presents the implementation methodology and the performance of this new regional tidal model in the Arctic Ocean, compared to the existing global tidal models.
Retrieval with Infrared Atmospheric Sounding Interferometer and Validation during JAIVEx
NASA Technical Reports Server (NTRS)
Zhou, Daniel K.; Liu, Xu; Larar, Allen M.; Smith, William L.; Taylor, Jonathan P.; Schluessel, Peter; Strow, L. Larrabee; Mango, Stephen A.
2008-01-01
A state-of-the-art IR-only retrieval algorithm has been developed with an all-season-global EOF Physical Regression and followed by 1-D Var. Physical Iterative Retrieval for IASI, AIRS, and NAST-I. The benefits of this retrieval are to produce atmospheric structure with a single FOV horizontal resolution (approx. 15 km for IASI and AIRS), accurate profiles above the cloud (at least) or down to the surface, surface parameters, and/or cloud microphysical parameters. Initial case study and validation indicates that surface, cloud, and atmospheric structure (include TBL) are well captured by IASI and AIRS measurements. Coincident dropsondes during the IASI and AIRS overpasses are used to validate atmospheric conditions, and accurate retrievals are obtained with an expected vertical resolution. JAIVEx has provided the data needed to validate the retrieval algorithm and its products which allows us to assess the instrument ability and/or performance. Retrievals with global coverage are under investigation for detailed retrieval assessment. It is greatly desired that these products be used for testing the impact on Atmospheric Data Assimilation and/or Numerical Weather Prediction.
NASA Technical Reports Server (NTRS)
King, Michael D.; Platnick, S.; Gray, M. A.; Hubanks, P. A.
2004-01-01
The Moderate Resolution Imaging Spectroradiometer (MODE) was developed by NASA and launched onboard the Terra spacecraft on December 18,1999 and the Aqua spacecraft on April 26,2002. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from each polar-orbiting, sun-synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 pm with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). In this paper, we describe the radiative properties of clouds as currently determined from satellites (cloud fraction, optical thickness, cloud top pressure, and cloud effective radius), and highlight the global and regional cloud microphysical properties currently available for assessing climate variability and forcing. These include the latitudinal distribution of cloud optical and radiative properties of both liquid water and ice clouds, as well as joint histograms of cloud optical thickness and effective radius for selected geographical locations around the globe.
Magnetic Fields of Lunar Impact Basins and Their Use in Constraining the Impact Process
NASA Astrophysics Data System (ADS)
Halekas, J. S.; Lin, R. P.
2003-01-01
Measurements by the Magnetometer/Electron Reflectometer instrument on the Lunar Prospector spacecraft, which completed its mapping mission in 1999, have been used to construct the first completely global maps of lunar crustal magnetic fields. Now, for the first time, we have a data set with global coverage and a sensitivity and resolution which allow us to investigate the magnetic fields of lunar impact basins and craters. As on the Earth, impact sites have a variety of magnetic signatures associated with them, ranging from nearly complete demagnetization to strong central magnetic anomalies. Observations of the magnetic fields of terrestrial basins have been used to make inferences about the impact process, and we wish to show that lunar observations can also provide valuable constraints.
Mapping the impacts of thermoelectric power generation: a global, spatially explicit database
NASA Astrophysics Data System (ADS)
Raptis, Catherine; Pfister, Stephan
2017-04-01
Thermoelectric power generation is associated with environmental pressures resulting from emissions to air and water, as well as water consumption. The need to achieve global coverage in related studies has become pressing in view of climate change. At the same time, the ability to quantify impacts from power production on a high resolution remains pertinent, given their highly regionalized nature, particularly when it comes to water-related impacts. Efforts towards global coverage have increased in recent years, but most work on the impacts of global electricity production presents a coarse geographical differentiation. Over the past few years we have begun a concerted effort to create and make available a global georeferenced inventory of thermoelectric power plant operational characteristics and emissions, by modelling the relevant processes on the highest possible level: that of a generating unit. Our work extends and enhances a commercially available global power plant database, and so far includes: - Georeferencing the generating units and populating the gaps in their steam properties. - Identifying the cooling system for 92% of the global installed thermoelectric power capacity. - Using the completed steam property data, along with local environmental temperature data, to systematically solve the Rankine cycle for each generating unit, involving: i) distinguishing between simple, reheat, and cogenerative cycles, and accounting for particularities in nuclear power cycles; ii) accounting for the effect of different cooling systems (once-through, recirculating (wet tower), dry cooling) on the thermodynamic cycle. One of the direct outcomes of solving the Rankine cycle is the cycle efficiency, an indispensable parameter in any study related to power production, including the quantification of air emissions and water consumption. Another direct output, for those units employing once-through cooling, is the rate of heat rejection to water, which can lead to thermal pollution. The opportunities afforded by the creation of this comprehensive database are numerous, including its use in integrated studies of electricity production and environmental burden, on local or global scales. The quantification, on the highest possible geographical and technological resolution, of all the different current impacts caused by thermoelectric power generation is crucial in order to conduct a proper assessment of the trade-offs in impacts in future scenario studies including technological changes, and to avoid burden-shifting. Here, we present the progress made in the building of the database so far, as well as the results of its application in a worldwide study of the thermal stress of rivers from the heat rejected by power plants using once-through cooling systems.
NASA Astrophysics Data System (ADS)
Vargas, Marco; Miura, Tomoaki; Csiszar, Ivan; Zheng, Weizhong; Wu, Yihua; Ek, Michael
2017-04-01
The first Joint Polar Satellite System (JPSS) mission, the Suomi National Polar-orbiting Partnership (S-NPP) satellite, was successfully launched in October, 2011, and it will be followed by JPSS-1, slated for launch in 2017. JPSS provides operational continuity of satellite-based observations and products for NOAA's Polar Operational Environmental Satellites (POES). Vegetation products derived from satellite measurements are used for weather forecasting, land modeling, climate research, and monitoring the environment including drought, the health of ecosystems, crop monitoring and forest fires. The operationally produced S-NPP VIIRS Vegetation Index (VI) Environmental Data Record (EDR) includes two vegetation indices: the Top of the Atmosphere (TOA) Normalized Difference Vegetation Index (NDVI), and the Top of the Canopy (TOC) Enhanced Vegetation Index (EVI). For JPSS-1, the S-NPP Vegetation Index EDR algorithm has been updated to include the TOC NDV. The current JPSS operational VI products are generated in granule style at 375 meter resolution at nadir, but these products in granule format cannot be ingested into NOAA operational monitoring and decision making systems. For that reason, the NOAA JPSS Land Team is developing a new global gridded Vegetation Index (VI) product suite for operational use by the NOAA National Centers for Environmental Prediction (NCEP). The new global gridded VIs will be used in the Multi-Physics (MP) version of the Noah land surface model (Noah-MP) in NCEP NOAA Environmental Modeling System (NEMS) for plant growth and data assimilation and to describe vegetation coverage and density in order to model the correct surface energy partition. The new VI 4km resolution global gridded products (TOA NDVI, TOC NDVI and TOC EVI) are being designed to meet the needs of directly ingesting vegetation index variables without the need to develop local gridding and compositing procedures. These VI products will be consistent with the already operational SNPP VIIRS Green Vegetation Fraction (GVF) global gridded 4km resolution. The ultimate goal is a global consistent set of global gridded land products at 1-km resolution to enable consistent use of the products in the full suite of global and regional NCEP land models. The new JPSS vegetation products system is scheduled to transition to operations in the fall of 2017.
Breaking new ground in mapping human settlements from space - The Global Urban Footprint
NASA Astrophysics Data System (ADS)
Esch, Thomas; Heldens, Wieke; Hirner, Andreas; Keil, Manfred; Marconcini, Mattia; Roth, Achim; Zeidler, Julian; Dech, Stefan; Strano, Emanuele
2017-12-01
Today, approximately 7.2 billion people inhabit the Earth and by 2050 this number will have risen to around nine billion, of which about 70% will be living in cities. The population growth and the related global urbanization pose one of the major challenges to a sustainable future. Hence, it is essential to understand drivers, dynamics, and impacts of the human settlements development. A key component in this context is the availability of an up-to-date and spatially consistent map of the location and distribution of human settlements. It is here that the Global Urban Footprint (GUF) raster map can make a valuable contribution. The new global GUF binary settlement mask shows a so far unprecedented spatial resolution of 0.4″ (∼ 12m) that provides - for the first time - a complete picture of the entirety of urban and rural settlements. The GUF has been derived by means of a fully automated processing framework - the Urban Footprint Processor (UFP) - that was used to analyze a global coverage of more than 180,000 TanDEM-X and TerraSAR-X radar images with 3 m ground resolution collected in 2011-2012. The UFP consists of five main technical modules for data management, feature extraction, unsupervised classification, mosaicking and post-editing. Various quality assessment studies to determine the absolute GUF accuracy based on ground truth data on the one hand and the relative accuracies compared to established settlements maps on the other hand, clearly indicate the added value of the new global GUF layer, in particular with respect to the representation of rural settlement patterns. The Kappa coefficient of agreement compared to absolute ground truth data, for instance, shows GUF accuracies which are frequently twice as high as those of established low resolution maps. Generally, the GUF layer achieves an overall absolute accuracy of about 85%, with observed minima around 65% and maxima around 98%. The GUF will be provided open and free for any scientific use in the full resolution and for any non-profit (but also non-scientific) use in a generalized version of 2.8″ (∼ 84m). Therewith, the new GUF layer can be expected to break new ground with respect to the analysis of global urbanization and peri-urbanization patterns, population estimation, vulnerability assessment, or the modeling of diseases and phenomena of global change in general.
The 1 km AVHRR global land data set: first stages in implementation
Eidenshink, J.C.; Faundeen, J.L.
1994-01-01
The global land 1 km data set project represents an international effort to acquire, archive, process, and distribute 1 km AVHRR data of the entire global land surface in order to meet the needs of the international science community. A network of 26 high resolution picture transmission (HRPT) stations, along with data recorded by the National Oceanic and Atmospheric Administration (NOAA), has been acquiring daily global land coverage since 1 April 1992. A data set of over 30000 AVHRR images has been archived and made available for distribution by the United States Geological Survey, EROS Data Center and the European Space Agency. Under the guidance of the International Geosphere Biosphere programme, processing standards for the AVHRR data have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NDVI) composites. The major uses of the composites are related to the study of surface vegetation cover. A prototype 10-day composite was produced for the period of 21–30 June 1992. Production of an 18-month time series of 10-day composites is underway.
A global flash flood forecasting system
NASA Astrophysics Data System (ADS)
Baugh, Calum; Pappenberger, Florian; Wetterhall, Fredrik; Hewson, Tim; Zsoter, Ervin
2016-04-01
The sudden and devastating nature of flash flood events means it is imperative to provide early warnings such as those derived from Numerical Weather Prediction (NWP) forecasts. Currently such systems exist on basin, national and continental scales in Europe, North America and Australia but rely on high resolution NWP forecasts or rainfall-radar nowcasting, neither of which have global coverage. To produce global flash flood forecasts this work investigates the possibility of using forecasts from a global NWP system. In particular we: (i) discuss how global NWP can be used for flash flood forecasting and discuss strengths and weaknesses; (ii) demonstrate how a robust evaluation can be performed given the rarity of the event; (iii) highlight the challenges and opportunities in communicating flash flood uncertainty to decision makers; and (iv) explore future developments which would significantly improve global flash flood forecasting. The proposed forecast system uses ensemble surface runoff forecasts from the ECMWF H-TESSEL land surface scheme. A flash flood index is generated using the ERIC (Enhanced Runoff Index based on Climatology) methodology [Raynaud et al., 2014]. This global methodology is applied to a series of flash floods across southern Europe. Results from the system are compared against warnings produced using the higher resolution COSMO-LEPS limited area model. The global system is evaluated by comparing forecasted warning locations against a flash flood database of media reports created in partnership with floodlist.com. To deal with the lack of objectivity in media reports we carefully assess the suitability of different skill scores and apply spatial uncertainty thresholds to the observations. To communicate the uncertainties of the flash flood system output we experiment with a dynamic region-growing algorithm. This automatically clusters regions of similar return period exceedence probabilities, thus presenting the at-risk areas at a spatial resolution appropriate to the NWP system. We then demonstrate how these warning areas could eventually complement existing global systems such as the Global Flood Awareness System (GloFAS), to give warnings of flash floods. This work demonstrates the possibility of creating a global flash flood forecasting system based on forecasts from existing global NWP systems. Future developments, in post-processing for example, will need to address an under-prediction bias, for extreme point rainfall, that is innate to current-generation global models.
100 New Impact Crater Sites Found on Mars
NASA Astrophysics Data System (ADS)
Kennedy, M. R.; Malin, M. C.
2009-12-01
Recent observations constrain the formation of 100 new impact sites on Mars over the past decade; 19 of these were found using the Mars Global Surveyor Mars Orbiter Camera (MOC), and the other 81 have been identified since 2006 using the Mars Reconnaissance Orbiter Context Camera (CTX). Every 6 meter/pixel CTX image is examined upon receipt and, where they overlap images of 0.3-240 m/pixel scale acquired by the same or other Mars-orbiting spacecraft, we look for features that may have changed. New impact sites are initially identified by the presence of a new dark spot or cluster of dark spots in a CTX image. Such spots may be new impact craters, or result from the effect of impact blasts on the dusty surface. In some (generally rare) cases, the crater is sufficiently large to be resolved in the CTX image. In most cases, however, the crater(s) cannot be seen. These are tentatively designated as “candidate” new impact sites, and the CTX team then creates an opportunity for the MRO spacecraft to point its cameras off-nadir and requests that the High Resolution Imaging Science Experiment (HiRISE) team obtain an image of ~0.3 m/pixel to confirm whether a crater or crater cluster is present. It is clear even from cursory examination that the CTX observations are areographically biased to dusty, higher albedo areas on Mars. All but 3 of the 100 new impact sites occur on surfaces with Lambert albedo values in excess of 23.5%. Our initial study of MOC images greatly benefited from the initial global observations made in one month in 1999, creating a baseline date from which we could start counting new craters. The global coverage by MRO Mars Color Imager is more than a factor of 4 poorer in resolution than the MOC Wide Angle camera and does not offer the opportunity for global analysis. Instead, we must rely on partial global coverage and global coverage that has taken years to accumulate; thus we can only treat impact rates statistically. We subdivide the total data set of 100 sites into 3 sets of observations: the original 19 MOC observations found in a survey of 15% of the planet, craters found only in CTX repeat coverage of 7% of Mars, and the remaining 69 craters found in a data set covering 40% of the planet. Using the mean interval between the latest observation preceding the impact and the first observation showing the impact for these groups of craters, we determine that the cratering rate is roughly 8 ± 6 x 10-7 craters/km2/yr for craters greater than ~1 m diameter. The cratering rate on Mars is sufficiently high to warrant consideration both for scientific studies and as a hazard to future exploration. Impacts are sufficiently frequent to act as seismic sources for studies of shallow crustal structure, if a seismic network is sufficiently dispersed and long-lived. Impacts large enough to provide information about deep interior structure are rare but probably occur on a decadal timescale. As recently noted in Science, new craters can be used to probe the distribution of subsurface ice and to provide samples from shallow depths that otherwise require meter-scale drilling systems. There is a finite probability that visitors to Mars for more than a month or two will hear or feel the effects of a nearby impact.
NASA Astrophysics Data System (ADS)
Lourens, L. J.; Beddow, H.; Liebrand, D.; Schrader, C.; Hilgen, F. J.
2016-12-01
Across the early to middle Miocene, high-resolution records from the Pacific Ocean indicate a dynamic climate system, encompassing a 2 Myr global warming event from 17 Ma to 14.7 Ma, followed by a major Cenozoic cooling step at 14.2 Ma -13.8 Ma. Currently, no high-resolution benthic record from the Atlantic Ocean exists covering both events, limiting global coverage of this intriguing period in Cenozoic climate evolution. Here, we present the first early to middle Miocene high-resolution from the Atlantic basin. These records, from Site 1264 on the Walvis Ridge, span a 5.5 Myr long interval (13.24-18.90 ma) in high temporal resolution ( 4 kyr) and are tuned to eccentricity. The d18O record shows a sudden (high-latitude) warming/deglaciation on Antarctica at 17.1 Ma, a rapid cooling/glaciation of Antarctica at 13.8 Ma, and high-amplitude ( 1‰) variability on astronomical time-scales throughout this interval. Together with other records from this time interval located in the Pacific, which show similar features, the data strongly suggests a highly dynamic global climate system. We find cooling steps in d18O at 14.7, 14.2 and 13.8 Ma, suggesting concurrent cooling in the Pacific and Atlantic deep waters during the MMCT. The benthic foraminiferal stable isotope records reveal that the dominant astronomical frequencies present at ODP Site 1264 during the early to middle Miocene interval are the 405 kyr and 110 kyr eccentricity periodicities. This is a contrast to other early to middle Miocene records from drill-sites in the Pacific and South China Sea, which show a strong expression of obliquity in particular between 14.2 and 14.7 Ma.
Global geological mapping of Ganymede
NASA Astrophysics Data System (ADS)
Patterson, G. Wesley; Collins, Geoffrey C.; Head, James W.; Pappalardo, Robert T.; Prockter, Louise M.; Lucchitta, Baerbel K.; Kay, Jonathan P.
2010-06-01
We have compiled a global geological map of Ganymede that represents the most recent understanding of the satellite based on Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. We discuss the material properties of geological units defined utilizing a global mosaic of the surface with a nominal resolution of 1 km/pixel assembled by the USGS with the best available Voyager and Galileo regional coverage and high resolution imagery (100-200 m/pixel) of characteristic features and terrain types obtained by the Galileo spacecraft. We also use crater density measurements obtained from our mapping efforts to examine age relationships amongst the various defined units. These efforts have resulted in a more complete understanding of the major geological processes operating on Ganymede, especially the roles of cryovolcanic and tectonic processes in the formation of might materials. They have also clarified the characteristics of the geological units that comprise the satellite's surface, the stratigraphic relationships of those geological units and structures, and the geological history inferred from those relationships. For instance, the characteristics and stratigraphic relationships of dark lineated material and reticulate material suggest they represent an intermediate stage between dark cratered material and light material units.
GNSS, Satellite Altimetry and Formosat-3/COSMIC for Determination of Ionosphere Parameters
NASA Astrophysics Data System (ADS)
Mahdi Alizadeh Elizei, M.; Schuh, Harald; Schmidt, Michael; Todorova, Sonya
The dispersion of ionosphere with respect to the microwave signals allows gaining information about the parameters of this medium in terms of the electron density (Ne), or the Total Elec-tron Content (TEC). In the last decade space geodetic techniques, such as Global Navigation Satellite System (GNSS), satellite altimetry missions, and Low Earth Orbiting (LEO) satel-lites have turned into a promising tool for remote sensing the ionosphere. The dual-frequency GNSS observations provide the main input data for development of Global Ionosphere Maps (GIM). However, the GNSS stations are heterogeneously distributed, with large gaps particu-larly over the sea surface, which lowers the precision of the GIM over these areas. Conversely, dual-frequency satellite altimetry missions provide information about the ionosphere precisely above the sea surface. In addition, LEO satellites such as Formosat-3/COSMIC (F-3/C) pro-vide well-distributed information of ionosphere around the world. In this study we developed GIMs of VTEC from combination of GNSS, satellite altimetry and F-3/C data with temporal resolution of 2 hours and spatial resolution of 5 degree in longitude and 2.5 degree in latitude. The combined GIMs provide a more homogeneous global coverage and higher precision and reliability than results of each individual technique.
In-Flight Performance of the TES Loop Heat Pipe Rejection System: Seven Years in Space
NASA Technical Reports Server (NTRS)
Rodriquez, Jose I.; Na-Nakornpanom, Arthur
2012-01-01
The Tropospheric Emission Spectrometer (TES) is an infrared, high spectral resolution Fourier transform spectrometer with a 3.3 to 15.4 micron wavelength coverage. TES is a scanning instrument intended for determining the chemical state of the Earth's lower atmosphere (troposphere) from the surface to 30+ km. TES produces vertical profiles of important pollutant and greenhouse gases such as carbon monoxide, ozone, methane, and water vapor on a global scale every other day. TES was launched into orbit onboard NASA's earth Observing System Aura spacecraft on July 15, 2004 from Vandenberg Air Force Base, California.
A merged surface reflectance product from the Landsat and Sentinel-2 Missions
NASA Astrophysics Data System (ADS)
Vermote, E.; Claverie, M.; Masek, J. G.; Becker-Reshef, I.; Justice, C. O.
2013-12-01
This project is aimed at producing a merged surface product from the Landsat and Sentinel-2 missions to ultimately achieve high temporal coverage (~2 days repeat cycle) at high spatial resolution (20-60m). The goal is to achieve a seamless/consistent stream of surface reflectance data from the different sensors. The first part of this presentation discusses the basic requirements of such a product and the necessary processing steps: mainly calibration, atmospheric corrections, BRDF effect corrections, spectral band pass adjustments and gridding. We demonstrate the performance of those different corrections by using MODIS and VIIRS (Climate Modeling Grid at 0.05deg) data globally as well as Formosat-2 (8m spatial resolution) data (one crop site in South of France where 105 scenes were acquired during 2006-2010). The consistency of the surface reflectance product from MODIS and Formosat-2 ranges from 6 to 8% relative depending on the spectral bands (Green to NIR) with a bias between 2% (NIR) to 5% (green), which is acceptable given the cumulated limitation in cross-calibration, atmospheric correction and BRDF correction. The second part is devoted to the simulation of the merged Landsat and Sentinel-2 mission by using Landsat-7, LDCM (early) and SPOT-4 Take 5 dataset. SPOT-4 Take 5 dataset is a collection of 42 sites distributed globally and systematically acquired by SPOT-4 HRV every 5 days during the decommissioning phase of the SPOT4 mission (February-May 2013). Finally, the benefits of such a merged surface reflectance at high spatial and temporal resolution are discussed within the context of the agricultural monitoring, in particular in the perspective of the GEOGLAM (Global Earth Observation for Global Land Agriculture Monitoring) project.
NASA Astrophysics Data System (ADS)
Matthews, L. D.; Crew, G. B.; Doeleman, S. S.; Lacasse, R.; Saez, A. F.; Alef, W.; Akiyama, K.; Amestica, R.; Anderson, J. M.; Barkats, D. A.; Baudry, A.; Broguière, D.; Escoffier, R.; Fish, V. L.; Greenberg, J.; Hecht, M. H.; Hiriart, R.; Hirota, A.; Honma, M.; Ho, P. T. P.; Impellizzeri, C. M. V.; Inoue, M.; Kohno, Y.; Lopez, B.; Martí-Vidal, I.; Messias, H.; Meyer-Zhao, Z.; Mora-Klein, M.; Nagar, N. M.; Nishioka, H.; Oyama, T.; Pankratius, V.; Perez, J.; Phillips, N.; Pradel, N.; Rottmann, H.; Roy, A. L.; Ruszczyk, C. A.; Shillue, B.; Suzuki, S.; Treacy, R.
2018-01-01
The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long Baseline Interferometry (VLBI) Data Exchange Format. These beamforming capabilities allow the ALMA array to collectively function as the equivalent of a single large aperture and participate in global VLBI arrays. The inclusion of phased ALMA in current VLBI networks operating at (sub)millimeter wavelengths provides an order of magnitude improvement in sensitivity, as well as enhancements in u–v coverage and north–south angular resolution. The availability of a phased ALMA enables a wide range of new ultra-high angular resolution science applications, including the resolution of supermassive black holes on event horizon scales and studies of the launch and collimation of astrophysical jets. It also provides a high-sensitivity aperture that may be used for investigations such as pulsar searches at high frequencies. This paper provides an overview of the ALMA Phasing System design, implementation, and performance characteristics.
[Estimation of desert vegetation coverage based on multi-source remote sensing data].
Wan, Hong-Mei; Li, Xia; Dong, Dao-Rui
2012-12-01
Taking the lower reaches of Tarim River in Xinjiang of Northwest China as study areaAbstract: Taking the lower reaches of Tarim River in Xinjiang of Northwest China as study area and based on the ground investigation and the multi-source remote sensing data of different resolutions, the estimation models for desert vegetation coverage were built, with the precisions of different estimation methods and models compared. The results showed that with the increasing spatial resolution of remote sensing data, the precisions of the estimation models increased. The estimation precision of the models based on the high, middle-high, and middle-low resolution remote sensing data was 89.5%, 87.0%, and 84.56%, respectively, and the precisions of the remote sensing models were higher than that of vegetation index method. This study revealed the change patterns of the estimation precision of desert vegetation coverage based on different spatial resolution remote sensing data, and realized the quantitative conversion of the parameters and scales among the high, middle, and low spatial resolution remote sensing data of desert vegetation coverage, which would provide direct evidence for establishing and implementing comprehensive remote sensing monitoring scheme for the ecological restoration in the study area.
High-Resolution Enceladus Atlas and Compositional Maps derived from Cassini ISS and VIMS
NASA Astrophysics Data System (ADS)
Roatsch, Thomas; Kersten, Elke; Wählisch, Marita; Hoffmeister, Angelika; Stephan, Katrin; Jaumann, Ralf
2010-05-01
The first version of the high-resolution Enceladus atlas was released in 2006 [1]. The Cassini Imaging Science Sub-system (ISS) acquired more high-resolution images (< 1 km/pixel) during five close flybys of Enceladus in 2008 and 2009. We combined these images with lower-resolution coverage taken between 2007 and 2009 to improve the high-resolution global mosaic of Enceladus. The whole mosaic was shifted by 3.5° to the West to be consistent with the IAU definition of the prime meridian location. This new global mosaic is the baseline for the second release of the high-resolution Enceladus atlas that consists again of 15 tiles mapped at a scale of 1:500,000. We proposed 29 additional names for features which will be used as nomenclature in the atlas. We are awaiting validation of the new nomenclature by the IAU. The new release of the atlas will be made available to the public through CICLOPS (http://ciclops.org) and PDS (http://pds.jpl.nasa.gov). The Cassini Visual and Infrared Imaging Spectrometer (VIMS) observed Enceladus during a couple of flybys between 2005 and 2009. This gave us the possibility to combine these data into a global VIMS mosaic. Based on this mosaic maps of Enceladus' spectral properties could be derived. Thus, global maps illustrating the spatial variations of the absorption band depth of water ice were calculated, which are indicative of varying sizes of the water ice particles [2]. The authors gratefully acknowledge the planning and operation work of their colleagues from the Cassini-ISS team lead by Carolyn Porco and from the Cassini-VIMS team lead by Robert Brown. [1] Roatsch, Th. et al., High-resolution Enceladus atlas derived from Cassini-ISS images. Planetary Space Sciences 56, 109-116, 2008. [2] Jaumann, R., Stephan, K., Hansen, G.B., Clark, R.N., Buratti, B.J., Brown, R.H., Baines, K.H., Newman, S.F., Bellucci, G., Filacchione, G., Coradini, A., Cruikshank, D.P., Griffith, C.A., Hibbitts, C.A., McCord, T.B., Nelson, R.M., Nicholson, P.D., Sotin, C., and Wagner, R., 2008: Distribution of icy particles across Enceladus' surface as derived from Cassini-VIMS measurements. Icarus 193.
O'Mahony, Patrick; Schäfer, Mike Steffen
2005-02-01
The essay compares German and Irish media coverage of human genome research in the year 2000, using qualitative and quantitative frame analysis of a print media corpus. Drawing from a media-theoretical account of science communication, the study examines four analytic dimensions: (1) the influence of global and national sources of discourse; (2) the nature of elaboration on important themes; (3) the extent of societal participation in discourse production; (4) the cultural conditions in which the discourse resonates. The analysis shows that a global discursive package, emphasizing claims of scientific achievement and medical progress, dominates media coverage in both countries. However, German coverage is more extensive and elaborate, and includes a wider range of participants. Irish coverage more often incorporates the global package without further elaboration. These finding indicate that the global package is 'localized' differently due to national patterns of interests, German participation in human genome research, traditions of media coverage, and the domestic resonance of the issue.
Mars global digital dune database: MC-30
Hayward, R.K.; Fenton, L.K.; Titus, T.N.; Colaprete, A.; Christensen, P.R.
2012-01-01
The Mars Global Digital Dune Database (MGD3) provides data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey Open-File Reports. The first report (Hayward and others, 2007) included dune fields from lat 65° N. to 65° S. (http://pubs.usgs.gov/of/2007/1158/). The second report (Hayward and others, 2010) included dune fields from lat 60° N. to 90° N. (http://pubs.usgs.gov/of/2010/1170/). This report encompasses ~75,000 km2 of mapped dune fields from lat 60° to 90° S. The dune fields included in this global database were initially located using Mars Odyssey Thermal Emission Imaging System (THEMIS) Infrared (IR) images. In the previous two reports, some dune fields may have been unintentionally excluded for two reasons: (1) incomplete THEMIS IR (daytime) coverage may have caused us to exclude some moderate- to large-size dune fields or (2) resolution of THEMIS IR coverage (100 m/pixel) certainly caused us to exclude smaller dune fields. In this report, mapping is more complete. The Arizona State University THEMIS daytime IR mosaic provided complete IR coverage, and it is unlikely that we missed any large dune fields in the South Pole (SP) region. In addition, the increased availability of higher resolution images resulted in the inclusion of more small (~1 km2) sand dune fields and sand patches. To maintain consistency with the previous releases, we have identified the sand features that would not have been included in earlier releases. While the moderate to large dune fields in MGD3 are likely to constitute the largest compilation of sediment on the planet, we acknowledge that our database excludes numerous small dune fields and some moderate to large dune fields as well. Please note that the absence of mapped dune fields does not mean that dune fields do not exist and is not intended to imply a lack of saltating sand in other areas. Where availability and quality of THEMIS visible (VIS), Mars Orbiter Camera (MOC) narrow angle, Mars Express High Resolution Stereo Camera, or Mars Reconnaissance Orbiter Context Camera and High Resolution Imaging Science Experiment images allowed, we classified dunes and included some dune slipface measurements, which were derived from gross dune morphology and represent the approximate prevailing wind direction at the last time of significant dune modification. It was beyond the scope of this report to look at the detail needed to discern subtle dune modification. It was also beyond the scope of this report to measure all slipfaces. We attempted to include enough slipface measurements to represent the general circulation (as implied by gross dune morphology) and to give a sense of the complex nature of aeolian activity on Mars. The absence of slipface measurements in a given direction should not be taken as evidence that winds in that direction did not occur. When a dune field was located within a crater, the azimuth from crater centroid to dune field centroid was calculated, as another possible indicator of wind direction. Output from a general circulation model is also included. In addition to polygons locating dune fields, the database includes ~700 of the THEMIS VIS and MOC images that were used to build the database.
NASA Technical Reports Server (NTRS)
King, Michael D.; Menzel, W. Paul; Kaufman, Yoram J.; Tanre, Didier; Gao, Bo-Cai; Platnick, Steven; Ackerman, Steven A.; Remer, Lorraine A.; Pincus, Robert; Hubanks, Paul A.
2003-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) is an earth-viewing sensor that flies on the Earth Observing System (EOS) Terra and Aqua satellites, launched in 1999 and 2002, respectively. MODIS scans a swath width of 2330 km that is sufficiently wide to provide nearly complete global coverage every two days from a polar-orbiting, sun-synchronous, platform at an altitude of 705 km. MODIS provides images in 36 spectral bands between 0.415 and 14.235 pm with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). These bands have been carefully selected to en- able advanced studies of land, ocean, and atmospheric properties. Twenty-six bands are used to derive atmospheric properties such as cloud mask, atmospheric profiles, aerosol properties, total precipitable water, and cloud properties. In this paper we describe each of these atmospheric data products, including characteristics of each of these products such as file size, spatial resolution used in producing the product, and data availability.
Gaia, an all-sky survey for standard photometry
NASA Astrophysics Data System (ADS)
Carrasco, J. M.; Weiler, M.; Jordi, C.; Fabricius, C.
2017-03-01
Gaia ESA's space mission (launched in 2013) includes two low resolution spectroscopic instruments (one in the blue, BP, and another in the red, RP, wavelength domains) to classify and derive the astrophysical parameters of the observed sources. As it is well known, Gaia is a full-sky unbiased survey down to about 20th magnitude. The scanning law yields a rather uniform coverage of the sky over the full extent (a minimum of 5 years) of the mission. Gaia data reduction is a global one over the full mission. Both sky coverage and data reduction strategy ensure an unprecedented all-sky homogeneous spectrophotometric survey. Certainly, that survey is of interest for current and future on-ground and space projects, like LSST, PLATO, EUCLID and J-PAS/J-PLUS among others. These projects will benefit from the large amount (more than one billion) and wide variety of objects observed by Gaia with good quality spectrophotometry. Synthetic photometry derived from Gaia spectrophotometry for any passband can be used to expand the set of standard sources for these new instruments to come. In the current Gaia data release scenario, BP/RP spectrophotometric data will be available in the third release (in 2018, TBC). Current preliminary results allow us to estimate the precision of synthetic photometry derived from the Gaia data. This already allows the preparation of the on-going and future surveys and space missions. We discuss here the exploitation of the Gaia spectrophotometry as standard reference due to its full-sky coverage and its expected photometric uncertainties derived from the low resolution Gaia spectra.
A Nested Phosphorus and Proton Coil Array for Brain Magnetic Resonance Imaging and Spectroscopy
Brown, Ryan; Lakshmanan, Karthik; Madelin, Guillaume; Parasoglou, Prodromos
2015-01-01
A dual-nuclei radiofrequency coil array was constructed for phosphorus and proton magnetic resonance imaging and spectroscopy of the human brain at 7 Tesla. An eight-channel transceive degenerate birdcage phosphorus module was implemented to provide whole-brain coverage and significant sensitivity improvement over a standard dual-tuned loop coil. A nested eight-channel proton module provided adequate sensitivity for anatomical localization without substantially sacrificing performance on the phosphorus module. The developed array enabled phosphorus spectroscopy, a saturation transfer technique to calculate the global creatine kinase forward reaction rate, and single-metabolite whole-brain imaging with 1.4 cm nominal isotropic resolution in 15 min (2.3 cm actual resolution), while additionally enabling 1 mm isotropic proton imaging. This study demonstrates that a multi-channel array can be utilized for phosphorus and proton applications with improved coverage and/or sensitivity over traditional single-channel coils. The efficient multi-channel coil array, time-efficient pulse sequences, and the enhanced signal strength available at ultra-high fields can be combined to allow volumetric assessment of the brain and could provide new insights into the underlying energy metabolism impairment in several neurodegenerative conditions, such as Alzheimer’s and Parkinson’s diseases, as well as mental disorders such as schizophrenia. PMID:26375209
A nested phosphorus and proton coil array for brain magnetic resonance imaging and spectroscopy.
Brown, Ryan; Lakshmanan, Karthik; Madelin, Guillaume; Parasoglou, Prodromos
2016-01-01
A dual-nuclei radiofrequency coil array was constructed for phosphorus and proton magnetic resonance imaging and spectroscopy of the human brain at 7T. An eight-channel transceive degenerate birdcage phosphorus module was implemented to provide whole-brain coverage and significant sensitivity improvement over a standard dual-tuned loop coil. A nested eight-channel proton module provided adequate sensitivity for anatomical localization without substantially sacrificing performance on the phosphorus module. The developed array enabled phosphorus spectroscopy, a saturation transfer technique to calculate the global creatine kinase forward reaction rate, and single-metabolite whole-brain imaging with 1.4cm nominal isotropic resolution in 15min (2.3cm actual resolution), while additionally enabling 1mm isotropic proton imaging. This study demonstrates that a multi-channel array can be utilized for phosphorus and proton applications with improved coverage and/or sensitivity over traditional single-channel coils. The efficient multi-channel coil array, time-efficient pulse sequences, and the enhanced signal strength available at ultra-high fields can be combined to allow volumetric assessment of the brain and could provide new insights into the underlying energy metabolism impairment in several neurodegenerative conditions, such as Alzheimer's and Parkinson's diseases, as well as mental disorders such as schizophrenia. Copyright © 2015 Elsevier Inc. All rights reserved.
Surface radiant flux densities inferred from LAC and GAC AVHRR data
NASA Astrophysics Data System (ADS)
Berger, F.; Klaes, D.
To infer surface radiant flux densities from current (NOAA-AVHRR, ERS-1/2 ATSR) and future meteorological (Envisat AATSR, MSG, METOP) satellite data, the complex, modular analysis scheme SESAT (Strahlungs- und Energieflüsse aus Satellitendaten) could be developed (Berger, 2001). This scheme allows the determination of cloud types, optical and microphysical cloud properties as well as surface and TOA radiant flux densities. After testing of SESAT in Central Europe and the Baltic Sea catchment (more than 400scenes U including a detailed validation with various surface measurements) it could be applied to a large number of NOAA-16 AVHRR overpasses covering the globe.For the analysis, two different spatial resolutions U local area coverage (LAC) andwere considered. Therefore, all inferred results, like global area coverage (GAC) U cloud cover, cloud properties and radiant properties, could be intercompared. Specific emphasis could be made to the surface radiant flux densities (all radiative balance compoments), where results for different regions, like Southern America, Southern Africa, Northern America, Europe, and Indonesia, will be presented. Applying SESAT, energy flux densities, like latent and sensible heat flux densities could also be determined additionally. A statistical analysis of all results including a detailed discussion for the two spatial resolutions will close this study.
NASA Technical Reports Server (NTRS)
Entekhabi, D.; Njoku, E. G.; Spencer, M.; Kim, Y.; Smith, J.; McDonald, K. C.; vanZyl, J.; Houser, P.; Dorion, T.; Koster, R.;
2004-01-01
The Hydrosphere State Mission (Hydros) is a pathfinder mission in the National Aeronautics and Space Administration (NASA) Earth System Science Pathfinder Program (ESSP). The objective of the mission is to provide exploratory global measurements of the earth's soil moisture at 10-km resolution with two- to three-days revisit and land-surface freeze/thaw conditions at 3-km resolution with one- to two-days revisit. The mission builds on the heritage of ground-based and airborne passive and active low-frequency microwave measurements that have demonstrated and validated the effectiveness of the measurements and associated algorithms for estimating the amount and phase (frozen or thawed) of surface soil moisture. The mission data will enable advances in weather and climate prediction and in mapping processes that link the water, energy, and carbon cycles. The Hydros instrument is a combined radar and radiometer system operating at 1.26 GHz (with VV, HH, and HV polarizations) and 1.41 GHz (with H, V, and U polarizations), respectively. The radar and the radiometer share the aperture of a 6-m antenna with a look-angle of 39 with respect to nadir. The lightweight deployable mesh antenna is rotated at 14.6 rpm to provide a constant look-angle scan across a swath width of 1000 km. The wide swath provides global coverage that meet the revisit requirements. The radiometer measurements allow retrieval of soil moisture in diverse (nonforested) landscapes with a resolution of 40 km. The radar measurements allow the retrieval of soil moisture at relatively high resolution (3 km). The mission includes combined radar/radiometer data products that will use the synergy of the two sensors to deliver enhanced-quality 10-km resolution soil moisture estimates. In this paper, the science requirements and their traceability to the instrument design are outlined. A review of the underlying measurement physics and key instrument performance parameters are also presented.
NASA Technical Reports Server (NTRS)
Scarino, Benjamin R.; Minnis, Patrick; Chee, Thad; Bedka, Kristopher M.; Yost, Christopher R.; Palikonda, Rabindra
2017-01-01
Surface skin temperature (T(sub s)) is an important parameter for characterizing the energy exchange at the ground/water-atmosphere interface. The Satellite ClOud and Radiation Property retrieval System (SatCORPS) employs a single-channel thermal-infrared (TIR) method to retrieve T(sub s) over clear-sky land and ocean surfaces from data taken by geostationary Earth orbit (GEO) and low Earth orbit (LEO) satellite imagers. GEO satellites can provide somewhat continuous estimates of T(sub s) over the diurnal cycle in non-polar regions, while polar T(sub s) retrievals from LEO imagers, such as the Advanced Very High Resolution Radiometer (AVHRR), can complement the GEO measurements. The combined global coverage of remotely sensed T(sub s), along with accompanying cloud and surface radiation parameters, produced in near-realtime and from historical satellite data, should be beneficial for both weather and climate applications. For example, near-realtime hourly T(sub s) observations can be assimilated in high-temporal-resolution numerical weather prediction models and historical observations can be used for validation or assimilation of climate models. Key drawbacks to the utility of TIR-derived T(sub s) data include the limitation to clear-sky conditions, the reliance on a particular set of analyses/reanalyses necessary for atmospheric corrections, and the dependence on viewing and illumination angles. Therefore, T(sub s) validation with established references is essential, as is proper evaluation of T(sub s) sensitivity to atmospheric correction source. This article presents improvements on the NASA Langley GEO satellite and AVHRR TIR-based T(sub s) product that is derived using a single-channel technique. The resulting clear-sky skin temperature values are validated with surface references and independent satellite products. Furthermore, an empirically adjusted theoretical model of satellite land surface temperature (LST) angular anisotropy is tested to improve satellite LST retrievals. Application of the anisotropic correction yields reduced mean bias and improved precision of GOES-13 LST relative to independent Moderate-resolution Imaging Spectroradiometer (MYD11_L2) LST and Atmospheric Radiation Measurement Program ground station measurements. It also significantly reduces inter-satellite differences between LSTs retrieved simultaneously from two different imagers. The implementation of these universal corrections into the SatCORPS product can yield significant improvement in near-global-scale, near-realtime, satellite-based LST measurements. The immediate availability and broad coverage of these skin temperature observations should prove valuable to modelers and climate researchers looking for improved forecasts and better understanding of the global climate model.
NASA Astrophysics Data System (ADS)
Hu, Rongming; Wang, Shu; Guo, Jiao; Guo, Liankun
2018-04-01
Impervious surface area and vegetation coverage are important biophysical indicators of urban surface features which can be derived from medium-resolution images. However, remote sensing data obtained by a single sensor are easily affected by many factors such as weather conditions, and the spatial and temporal resolution can not meet the needs for soil erosion estimation. Therefore, the integrated multi-source remote sensing data are needed to carry out high spatio-temporal resolution vegetation coverage estimation. Two spatial and temporal vegetation coverage data and impervious data were obtained from MODIS and Landsat 8 remote sensing images. Based on the Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model (ESTARFM), the vegetation coverage data of two scales were fused and the data of vegetation coverage fusion (ESTARFM FVC) and impervious layer with high spatiotemporal resolution (30 m, 8 day) were obtained. On this basis, the spatial variability of the seepage-free surface and the vegetation cover landscape in the study area was measured by means of statistics and spatial autocorrelation analysis. The results showed that: 1) ESTARFM FVC and impermeable surface have higher accuracy and can characterize the characteristics of the biophysical components covered by the earth's surface; 2) The average impervious surface proportion and the spatial configuration of each area are different, which are affected by natural conditions and urbanization. In the urban area of Xi'an, which has typical characteristics of spontaneous urbanization, landscapes are fragmented and have less spatial dependence.
Monitoring Ocean CO2 Fluxes from Space: GOSAT and OCO-2
NASA Technical Reports Server (NTRS)
Crisp, David
2012-01-01
The ocean is a major component of the global carbon cycle, emitting over 330 billion tons of carbon dioxide (CO2) into the atmosphere each year, or about 10 times that emitted fossil fuel combustion and all other human activities [1, 2]. The ocean reabsorbs a comparable amount of CO2 each year, along with 25% of the CO2 emitted by these human activities. The nature and geographic distribution of the processes controlling these ocean CO2 fluxes are still poorly constrained by observations. A better understanding of these processes is essential to predict how this important CO2 sink may evolve as the climate changes.While in situ measurements of ocean CO2 fluxes can be very precise, the sampling density is far too sparse to quantify ocean CO2 sources and sinks over much of the globe. One way to improve the spatial resolution, coverage, and sampling frequency is to make observations of the column averaged CO2 dry air mole fraction, XCO2, from space [4, 5, 6]. Such measurements could provide global coverage at high resolution (< 100 km) on monthly time scales. High precision (< 1 part per million, ppm) is essential to resolve the small, near-surface CO2 variations associated with ocean fluxes and to better constrain the CO2 transport over the ocean. The Japanese Greenhouse gases Observing Satellite (GOSAT) and the NASA Orbiting Carbon Observatory (OCO) were first two space based sensors designed specifically for this task. GOSAT was successfully launched on January 23, 2009, and has been returning measurements of XCO2 since April 2009. The OCO mission was lost in February 2009, when its launch vehicle malfunctioned and failed to reach orbit. In early 2010, NASA authorized a re-flight of OCO, called OCO-2, which is currently under development.
Spatial Metadata for Global Change Investigations Using Remote Sensing
NASA Technical Reports Server (NTRS)
Emerson, Charles W.; Quattrochi, Dale A.; Lam, Nina Siu-Ngan; Arnold, James E. (Technical Monitor)
2002-01-01
Satellite and aircraft-borne remote sensors have gathered petabytes of data over the past 30+ years. These images are an important resource for establishing cause and effect relationships between human-induced land cover changes and alterations in climate and other biophysical patterns at local to global scales. However, the spatial, temporal, and spectral characteristics of these datasets vary, thus complicating long-term studies involving several types of imagery. As the geographical and temporal coverage, the spectral and spatial resolution, and the number of individual sensors increase, the sheer volume and complexity of available data sets will complicate management and use of the rapidly growing archive of earth imagery. Mining this vast data resource for images that provide the necessary information for climate change studies becomes more difficult as more sensors are launched and more imagery is obtained.
Satellite Remote Sensing: Passive-Microwave Measurements of Sea Ice
NASA Technical Reports Server (NTRS)
Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)
2001-01-01
Satellite passive-microwave measurements of sea ice have provided global or near-global sea ice data for most of the period since the launch of the Nimbus 5 satellite in December 1972, and have done so with horizontal resolutions on the order of 25-50 km and a frequency of every few days. These data have been used to calculate sea ice concentrations (percent areal coverages), sea ice extents, the length of the sea ice season, sea ice temperatures, and sea ice velocities, and to determine the timing of the seasonal onset of melt as well as aspects of the ice-type composition of the sea ice cover. In each case, the calculations are based on the microwave emission characteristics of sea ice and the important contrasts between the microwave emissions of sea ice and those of the surrounding liquid-water medium.
MISR Level 2 TOA/Cloud Classifier parameters (MIL2TCCL_V3)
NASA Technical Reports Server (NTRS)
Diner, David J. (Principal Investigator)
The TOA/Cloud Classifiers contain the Angular Signature Cloud Mask (ASCM), a scene classifier calculated using support vector machine technology (SVM) both of which are on a 1.1 km grid, and cloud fractions at 17.6 km resolution that are available in different height bins (low, middle, high) and are also calculated on an angle-by-angle basis. [Temporal_Coverage: Start_Date=2000-02-24; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=1.1 km; Longitude_Resolution=1.1 km; Temporal_Resolution=about 15 orbits/day].
1987-10-15
apparent shift of this band to higher energy with increasing coverage, observed at lower resolution (but higher sensitivity) in electron energy loss...apparent shift of this band to higher energy with increasing coverage, observed at lower resolution (but higher sen- sitivity) in electron energy ...11 using high-resolution electron energy -loss spectroscopy (EELS), is especially intriguing. 02 dissociates on this surface to populate two types of
A Constellation of CubeSat InSAR Sensors for Rapid-Revisit Surface Deformation Studies
NASA Astrophysics Data System (ADS)
Wye, L.; Lee, S.; Yun, S. H.; Zebker, H. A.; Stock, J. D.; Wicks, C. W., Jr.; Doe, R.
2016-12-01
The 2007 NRC Decadal Survey for Earth Sciences highlights three major Earth surface deformation themes: 1) solid-earth hazards and dynamics; 2) human health and security; and 3) land-use change, ecosystem dynamics and biodiversity. Space-based interferometric synthetic aperture radar (InSAR) is a key change detection tool for addressing these themes. Here, we describe the mission and radar payload design for a constellation of S-band InSAR sensors specifically designed to provide the global, high temporal resolution, sub-cm level deformation accuracy needed to address some of the major Earth system goals. InSAR observations with high temporal resolution are needed to properly monitor certain nonlinearly time-varying features (e.g., unstable volcanoes, active fault lines, and heavily-used groundwater or hydrocarbon reservoirs). Good temporal coverage is also needed to reduce atmospheric artifacts by allowing multiple acquisitions to be averaged together, since each individual SAR measurement is corrupted by up to several cm of atmospheric noise. A single InSAR platform is limited in how often it can observe a given scene without sacrificing global spatial coverage. Multiple InSAR platforms provide the spatial-temporal flexibility required to maximize the science return. However, building and launching multiple InSAR platforms is cost-prohibitive for traditional satellites. SRI International (SRI) and our collaborators are working to exploit developments in nanosatellite technology, in particular the emergence of the CubeSat standard, to provide high-cadence InSAR capabilities in an affordable package. The CubeSat Imaging Radar for Earth Science (CIRES) subsystem, a prototype SAR electronics package developed by SRI with support from a 2014 NASA ESTO ACT award, is specifically scaled to be a drop-in radar solution for resource-limited delivery systems like CubeSats and small airborne vehicles. Here, we present our mission concept and flow-down requirements for a constellation of 6U InSAR sensors that individually approach the performance capabilities of existing instruments, but collectively surpass the temporal coverage capabilities of single-platform sensors. We discuss the key applications addressed by this constellation and the capabilities that the constellation enables.
The ATOVS and AVHRR product processing facility for EPS
NASA Astrophysics Data System (ADS)
Klaes, D.; Ackermann, J.; Schraidt, R.; Patterson, T.; Schlüssel, P.; Phillips, P.; Arriaga, A.; Grandell, J.
The ATOVS/AVHRR Product Processing Facility (PPF) of the EPS (EUMETSAT Polar System) Core Ground Segment comprises the Level 1 processing of the data from the ATOVS sounding instruments AMSU-A, MHS and HIRS/4, and the imager AVHRR/3 into calibrated and navigated radiances. A second component includes the level 2 processing, which uses as input the level 1 products of the aforementioned instruments. The specification of the PPF is based on two well-known and well-established software packages, which have been used by the international community for some years: The AAPP (ATOVS and AVHRR Pre-processing Package) and ICI (Inversion Coupled with Imager). The PPF is able to process data from instruments flown on the Metop and NOAA satellites. For the level 1 processing of the sounding instruments' data (HIRS, AMSU-A and MHS), the basic functionality of AAPP has been kept; however, the individual chains for each instrument have been separated and additional functionality has been integrated. For HIRS a global calibration, as performed by NOAA/NESDIS today, has been included. For AMSU-A and MHS the moon contamination of the calibration space view can be corrected for. Additional functionality has also been included in the AVHRR processing. In particular, an enhanced navigation by landmark processing has been implemented to ensure accurate geo-location. Additionally, the PPF can digest and process the global AVHRR data either at full pixel resolution (1 km at nadir), which is the nominal mode for the Metop processing, or at the reduced resolution of the NOAA/GAC (Global Area Coverage) data (about 4 km resolution at nadir). For the level 2 processing the ICI had to be modified to include the most recent improvement in fast radiative transfer modelling as included in the RTTOV-7. As a first step towards the realisation of the PPF a prototype has been generated for the purpose to help specifying the details of the PPF, and for verification of the latter by generation of reference and test data. The prototype is able to process HRPT data, GAC data from the NOAA satellite active archive (SAA), and also Local Area Coverage (LAC) data. GAC data processing means that the processing of whole orbits is possible. Current work is aimed to assess the quality of the Level 2 retrievals and to generate reference test data for the operational PPF.
A global digital elevation model - GTOP030
1999-01-01
GTOP030, the U.S. Geological Survey's (USGS) digital elevation model (DEM) of the Earth, provides the flrst global coverage of moderate resolution elevation data. The original GTOP30 data set, which was developed over a 3-year period through a collaborative effort led by the USGS, was completed in 1996 at the USGS EROS Data Center in Sioux Falls, South Dakota. The collaboration involved contributions of staffing, funding, or source data from cooperators including the National Aeronautics and Space Administration (NASA), the United Nations Environment Programme Global Resource Information Database (UNEP/GRID), the U.S. Agency for International Development (USAID), the Instituto Nacional de Estadistica Geografia e Informatica (INEGI) of Mexico, the Geographical Survey Institute (GSI) of Japan, Manaaki Whenua Landcare Research of New Zealand, and the Scientific Committee on Antarctic Research (SCAR). In 1999, work was begun on an update to the GTOP030 data set. Additional data sources are being incorporated into GTOP030 with an enhanced and improved data set planned for release in 2000.
NASA Technical Reports Server (NTRS)
Mccleese, D. J.; Haskins, R. D.; Schofield, J. T.; Zurek, R. W.; Leovy, C. B.; Paige, D. A.; Taylor, F. W.
1992-01-01
Studies of the climate and atmosphere of Mars are limited at present by a lack of meteorological data having systematic global coverage with good horizontal and vertical resolution. The Mars Observer spacecraft in a low, nearly circular, polar orbit will provide an excellent platform for acquiring the data needed to advance significantly our understanding of the Martian atmosphere and its remarkable variability. The Mars Observer pressure modulator infrared radiometer (PMIRR) is a nine-channel limb and nadir scanning atmospheric sounder which will observe the atmosphere of Mars globally from 0 to 80 km for a full Martian year. PMIRR employs narrow-band radiometric channels and two pressure modulation cells to measure atmospheric and surface emission in the thermal infrared. PMIRR infrared and visible measurements will be combined to determine the radiative balance of the polar regions, where a sizeable fraction of the global atmospheric mass annually condenses onto and sublimes from the surface. Derived meteorological fields, including diabatic heating and cooling and the vertical variation of horizontal winds, are computed from the globally mapped fields retrieved from PMIRR data.
Book Review: Regional Hydrological Response to Climate Change
NASA Technical Reports Server (NTRS)
Koster, Randal
1998-01-01
The book being reviewed, Regional Hydrological Response to Climate Change, addresses the effects of global climate change, particularly global warming induced by greenhouse gas emissions, on hydrological budgets at the regional scale. As noted in its preface, the book consists of peer-reviewed papers delivered at scientific meetings held by the International Geographical Union Working Group on Regional Hydrological Response to Climate Change and Global Warming, supplemented with some additional chapters that round out coverage of the topic. The editors hope that this book will serve as "not only a record of current achievements, but also a stimulus to further hydrological research as the detail and spatial resolution of Global Climate Models improves". The reviewer found the background material on regional climatology to be valuable and the methodologies presented to be of interest. The value of the book is significantly diminished, however by the dated nature of some of the material and by large uncertainties in the predictions of regional precipitation change. The book would have been improved by a much more extensive documentation of the uncertainty associated with each step of the prediction process.
Internal Consistency of the NVAP Water Vapor Dataset
NASA Technical Reports Server (NTRS)
Suggs, Ronnie J.; Jedlovec, Gary J.; Arnold, James E. (Technical Monitor)
2001-01-01
The NVAP (NASA Water Vapor Project) dataset is a global dataset at 1 x 1 degree spatial resolution consisting of daily, pentad, and monthly atmospheric precipitable water (PW) products. The analysis blends measurements from the Television and Infrared Operational Satellite (TIROS) Operational Vertical Sounder (TOVS), the Special Sensor Microwave/Imager (SSM/I), and radiosonde observations into a daily collage of PW. The original dataset consisted of five years of data from 1988 to 1992. Recent updates have added three additional years (1993-1995) and incorporated procedural and algorithm changes from the original methodology. Since each of the PW sources (TOVS, SSM/I, and radiosonde) do not provide global coverage, each of these sources compliment one another by providing spatial coverage over regions and during times where the other is not available. For this type of spatial and temporal blending to be successful, each of the source components should have similar or compatible accuracies. If this is not the case, regional and time varying biases may be manifested in the NVAP dataset. This study examines the consistency of the NVAP source data by comparing daily collocated TOVS and SSM/I PW retrievals with collocated radiosonde PW observations. The daily PW intercomparisons are performed over the time period of the dataset and for various regions.
Estimating Global Impervious Surface based on Social-economic Data and Satellite Observations
NASA Astrophysics Data System (ADS)
Zeng, Z.; Zhang, K.; Xue, X.; Hong, Y.
2016-12-01
Impervious surface areas around the globe are expanding and significantly altering the surface energy balance, hydrology cycle and ecosystem services. Many studies have underlined the importance of impervious surface, r from hydrological modeling to contaminant transport monitoring and urban development estimation. Therefore accurate estimation of the global impervious surface is important for both physical and social sciences. Given the limited coverage of high spatial resolution imagery and ground survey, using satellite remote sensing and geospatial data to estimate global impervious areas is a practical approach. Based on the previous work of area-weighted imperviousness for north branch of the Chicago River provided by HDR, this study developed a method to determine the percentage of impervious surface using latest global land cover categories from multi-source satellite observations, population density and gross domestic product (GDP) data. Percent impervious surface at 30-meter resolution were mapped. We found that 1.33% of the CONUS (105,814 km2) and 0.475% of the land surface (640,370km2) are impervious surfaces. To test the utility and practicality of the proposed method, National Land Cover Database (NLCD) 2011 percent developed imperviousness for the conterminous United States was used to evaluate our results. The average difference between the derived imperviousness from our method and the NLCD data across CONUS is 1.14%, while difference between our results and the NLCD data are within ±1% over 81.63% of the CONUS. The distribution of global impervious surface map indicates that impervious surfaces are primarily concentrated in China, India, Japan, USA and Europe where are highly populated and/or developed. This study proposes a straightforward way of mapping global imperviousness, which can provide useful information for hydrologic modeling and other applications.
Interactively Browsing NASA's EOS Imagery in Full Resolution
NASA Astrophysics Data System (ADS)
Boller, R. A.; Joshi, T.; Schmaltz, J. E.; Ilavajhala, S.; Davies, D.; Murphy, K. J.
2012-12-01
Worldview is a new tool designed to interactively browse full-resolution imagery from NASA's fleet of Earth Observing System (EOS) satellites. It is web-based and developed using open standards (JavaScript, CSS, HTML) for cross-platform compatibility. It addresses growing user demands for access to full-resolution imagery by providing a responsive, interactive interface with global coverage, no artificial boundaries, and views in geographic and polar projections. Currently tailored to the near real-time community, Worldview enables the rapid evaluation and comparison of imagery related to such application areas as fires, floods, and air quality. It is supported by the Global Imagery Browse Services (GIBS), a system that continuously ingests, mosaics, and serves approximately 21GB of imagery daily. This imagery spans over 50 data products that are available within three hours of observation from instruments aboard Terra, Aqua, and Aura. The GIBS image archive began in May 2012 and will have published approximately 4.4TB of imagery as of December 2012. Worldview facilitates rapid access to this archive and is supplemented by socioeconomic data layers from the Socioeconomic Data and Applications Center (SEDAC), including products such as population density and economic risk from cyclones. Future plans include the accessibility of additional products that cover the entire Terra/MODIS and Aqua/MODIS missions (>150TB) and the ability to download the underlying science data of the onscreen imagery.
Global Soil Information Facilities - Component Worldgrids.org
NASA Astrophysics Data System (ADS)
Reuter, H. I.; Hengl, T.
2012-04-01
GSIF (Global Soil Information Facilities) is ISRIC's framework for production of open soil data. It has been inspired by global environmental data initiatives (e.g. oneGeology, GBIF). The main practical motivation for GSIF is to build cyber-infrastructure to collate legacy (i.e., historic) soil data currently under threat of being lost forever and to generate new soil information. The objective of the component worldgrids is a (de)-central repository for collecting, storing, accessing and interacting with gridded data sets of global soil covariate data for production mapping, while being part of a larger GSIF. It is the physical implementation of the expectation that ISRIC would lead and coordinate a project to assemble a core data set of global environmental covariates to (partly) support local efforts to produce global soil property maps. Currently over 100 layers with a 5 and 1 km resolution with a global coverage can be accessed via www.worldgrids.org. Three different functionalities are implemented to extract data in an OGC complained matter: i) single point overlay ii) mass point overlay; iii) zone grid overlay with reporting of different statistical parameters. The presentation will focus on datasets, functionalities, access via the R-project and ArcGIS globalsoilmap.net Toolbox as well on future enhancements to the worldgrids platform.
The use of PROBA-V data for Global Agricultural Monitoring
NASA Astrophysics Data System (ADS)
Bydekerke, Lieven; Gilliams, Sven; Kempeneers, Pieter; Piccard, Isabelle; Deronde, Bart; Eerens, Herman; Gobin, Anne
2015-04-01
Land conversion, forest cutting, urban growth, agricultural expansion, take place at an unprecedented rate and scale such that they have a strong economic and environmental impact. Understanding and measuring dynamics becomes a prerequisite for companies, governments, agencies, NGO's, research institutes and society in general. In many cases the temporal frequency of the information is a requirement to detect phenomena that can occur within a few days and at a certain geographic scale. For example frequent updates on crop condition and projected production are needed to stabilise agricultural markets. Large initiatives such as the GEOGLAM AMIS (Group on Earth Observations Global Agricultural Monitoring - Agricultural Market Information System) respond to this increased need. Observations over large areas are available through satellites, however, the following challenges remain: • obtaining frequent and consistent observations at sufficient level of detail to identify spatial phenomena. At present, no single mission is capable of providing near daily information of any place in the world at scales appropriate to detect land cover/use changes in a consistent manner. • the need for a historical reference. For agricultural monitoring and early warning purposes the comparison of the actual data with a historical reference is of the utmost importance. The PROBA-V mission is an important attempt to overcome these challenges. From its design and within the GIO-Global Land component a lot of work has been done to ensure the consistency between the PROBA-V data and the 15 years historical archive of SPOT-VEGETATION. In this respect PROBA-V observations are comparable with the SPOT-VEGETATION historical baseline and will therefore ensure the continuation of the standard agricultural monitoring products. Next to this integration with the historical archive, PROBA -V also provides an increase in spatial resolution from 1km to 300m and even 100m. The latter ensures a global coverage every 5 days, while daily global coverage is provided at 1 km and 300 m. Within the framework of the FP7 SIGMA project (Stimulating Innovation for Global Monitoring of Agriculture), currently Europe's largest contribution to the abovementioned GEOGLAM initiative, the use of the 100m data set for agricultural monitoring is investigated. To overcome the problem of the reduced revisit time of the 100 m data, the SIGMA projects foresees in a data assimilation of the 100 m and 300 m products. The data assimilation is based on a Kalman filter approach developed by Sedano et al. (2014). As an output, a cloud free composite is produced every ten days at a spatial resolution of 100 m. References Sedano, Fernando, Pieter Kempeneers, and George Hurtt. "A Kalman Filter-Based Method to Generate Continuous Time Series of Medium-Resolution NDVI Images." Remote Sensing 6.12 (2014): 12381-12408. http://proba-v.vgt.vito.be/ http://www.geoglam-sigma.info/
NASA Technical Reports Server (NTRS)
Flower, D. A.; Peckham, G. E.
1978-01-01
An instrument to measure atmospheric pressure at the earth's surface from an orbiting satellite would be a valuable addition to the expanding inventory of remote sensors. The subject of this report is such an instrument - the Microwave Pressure Sounder (MPS). It is shown that global-ocean coverage is attainable with sufficient accuracy, resolution and observational frequency for meteorological, oceanographic and climate research applications. Surface pressure can be deduced from a measurement of the absorption by an atmospheric column at a frequency in the wing of the oxygen band centered on 60 GHz. An active multifrequency instrument is needed to make this measurement with sufficient accuracy. The selection of optimum operating frequencies is based upon accepted models of surface reflection, oxygen, water vapor and cloud absorption. Numerical simulation using a range of real atmospheres defined by radiosonde observations were used to validate the frequency selection procedure. Analyses are presented of alternative system configurations that define the balance between accuracy and achievable resolution.
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2003-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-09-16] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=1998-08-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product contains one hour of instantaneous Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The SSF combines instantaneous CERES data with scene information from a higher-resolution imager such as Visible/Infrared Scanner (VIRS) on TRMM or Moderate-Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua. Scene identification and cloud properties are defined at the higher imager resolution and these data are averaged over the larger CERES footprint. For each CERES footprint, the SSF contains the number of cloud layers and for each layer the cloud amount, height, temperature, pressure, optical depth, emissivity, ice and liquid water path, and water particle size. The SSF also contains the CERES filtered radiances for the total, shortwave (SW), and window (WN) channels and the unfiltered SW, longwave (LW), and WN radiances. The SW, LW, and WN radiances at spacecraft altitude are converted to Top-of-the-Atmosphere (TOA) fluxes based on the imager defined scene. These TOA fluxes are used to estimate surface fluxes. Only footprints with adequate imager coverage are included on CER_SSF_TRMM-PFM-VIRS_Subset_Edition1the SSF which is much less than the full set of footprints on the CERES ES-8 product. The following CERES SSF data sets are currently available: CER_SSF_TRMM-PFM-VIRS_Edition1 CER_SSF_TRMM-PFM-VIRS_Subset_Edition1 CER_SSF_TRMM-PFM-VIRS_Edition2A CER_SSF_TRMM-SIM-VIRS_Edition2_VIRSonly CER_SSF_TRMM-PFM-VIRS_Edition2A-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B-TransOps CER_SSF_TRMM-PFM-VIRS_Edition2B CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition1A CER_SSF_Terra-FM1-MODIS_Edition2A CER_SSF_Terra-FM2-MODIS_Edition2A CER_SSF_Terra-FM1-MODIS_Edition2B CER_SSF_Terra-FM2-MODIS_Edition2B CER_SSF_Aqua-FM4-MODIS_Beta1 CER_SSF_Aqua-FM3-MODIS_Beta2 CER_SSF_Aqua-FM4-MODIS_Beta2. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2003-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 hour; Temporal_Resolution_Range=Hourly - < Daily].
Retrieval of aerosol optical properties using MERIS observations: Algorithm and some first results.
Mei, Linlu; Rozanov, Vladimir; Vountas, Marco; Burrows, John P; Levy, Robert C; Lotz, Wolfhardt
2017-08-01
The MEdium Resolution Imaging Spectrometer (MERIS) instrument on board ESA Envisat made measurements from 2002 to 2012. Although MERIS was limited in spectral coverage, accurate Aerosol Optical Thickness (AOT) from MERIS data are retrieved by using appropriate additional information. We introduce a new AOT retrieval algorithm for MERIS over land surfaces, referred to as eXtensible Bremen AErosol Retrieval (XBAER). XBAER is similar to the "dark-target" (DT) retrieval algorithm used for Moderate-resolution Imaging Spectroradiometer (MODIS), in that it uses a lookup table (LUT) to match to satellite-observed reflectance and derive the AOT. Instead of a global parameterization of surface spectral reflectance, XBAER uses a set of spectral coefficients to prescribe surface properties. In this manner, XBAER is not limited to dark surfaces (vegetation) and retrieves AOT over bright surface (desert, semiarid, and urban areas). Preliminary validation of the MERIS-derived AOT and the ground-based Aerosol Robotic Network (AERONET) measurements yield good agreement, the resulting regression equation is y = (0.92 × ± 0.07) + (0.05 ± 0.01) and Pearson correlation coefficient of R = 0.78. Global monthly means of AOT have been compared from XBAER, MODIS and other satellite-derived datasets.
The Ozone Monitoring Instrument: overview of 14 years in space
NASA Astrophysics Data System (ADS)
Levelt, Pieternel F.; Joiner, Joanna; Tamminen, Johanna; Pepijn Veefkind, J.; Bhartia, Pawan K.; Stein Zweers, Deborah C.; Duncan, Bryan N.; Streets, David G.; Eskes, Henk; van der A, Ronald; McLinden, Chris; Fioletov, Vitali; Carn, Simon; de Laat, Jos; DeLand, Matthew; Marchenko, Sergey; McPeters, Richard; Ziemke, Jerald; Fu, Dejian; Liu, Xiong; Pickering, Kenneth; Apituley, Arnoud; González Abad, Gonzalo; Arola, Antti; Boersma, Folkert; Miller, Christopher Chan; Chance, Kelly; de Graaf, Martin; Hakkarainen, Janne; Hassinen, Seppo; Ialongo, Iolanda; Kleipool, Quintus; Krotkov, Nickolay; Li, Can; Lamsal, Lok; Newman, Paul; Nowlan, Caroline; Suleiman, Raid; Gijsbert Tilstra, Lieuwe; Torres, Omar; Wang, Huiqun; Wargan, Krzysztof
2018-04-01
This overview paper highlights the successes of the Ozone Monitoring Instrument (OMI) on board the Aura satellite spanning a period of nearly 14 years. Data from OMI has been used in a wide range of applications and research resulting in many new findings. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. With the operational very fast delivery (VFD; direct readout) and near real-time (NRT) availability of the data, OMI also plays an important role in the development of operational services in the atmospheric chemistry domain.
Remote Sensing Studies Of The Current Martian Climate
NASA Astrophysics Data System (ADS)
Taylor, F. W.; McCleese, D. J.; Schofield, J. T.; Calcutt, S. B.; Moroz, V. I.
A systematic and detailed experimental study of the Martian atmosphere remains to be carried out, despite many decades of intense interest in the nature of the Martian climate system, its interactions, variability and long-term stability. Such a study is planned by the 2005 Mars Reconnaissance Orbiter, using limb-scanning infrared radiometric techniques similar to those used to study trace species in the terrestrial stratosphere. For Mars, the objectives are temperature, humidity, dust and condensate abundances with high vertical resolution and global coverage in the 0 to 80 km height range. The paper will discuss the experiment and its methodology and expectations for the results.
The Ozone Monitoring Instrument: overview of 14 years in space
NASA Technical Reports Server (NTRS)
Tamminen, Johanna; Veefkind, J. Pepijn; van der A, Ronald; Miller, Christopher Chan; Ialongo, Iolanda; Kleipool, Quintus; Lamsal, Lok N.; Wang, Huiqun; Bhartia, Pawan K.; Zweers, Deborah C. Stein;
2018-01-01
This overview paper highlights the successes of the Ozone Monitoring Instrument (OMI) on board the Aura satellite spanning a period of nearly 14 years. Data from OMI has been used in a wide range of applications and research resulting in many new findings. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. With the operational very fast delivery (VFD; direct readout) and near real-time (NRT) availability of the data, OMI also plays an important role in the development of operational services in the atmospheric chemistry domain.
NASA Astrophysics Data System (ADS)
Becker, K. J.; Robinson, M. S.; Becker, T. L.; Weller, L. A.; Turner, S.; Nguyen, L.; Selby, C.; Denevi, B. W.; Murchie, S. L.; McNutt, R. L.; Solomon, S. C.
2009-12-01
In 2008 the MESSENGER spacecraft made two close flybys (M1 and M2) of Mercury and imaged about 74% of the planet at a resolution of 1 km per pixel, and at higher resolution for smaller portions of the planet. The Mariner 10 spacecraft imaged about 42% of Mercury’s surface more than 30 years ago. Combining image data collected by the two missions yields coverage of about 83% of Mercury’s surface. MESSENGER will perform its third and final flyby of Mercury (M3) on 29 September 2009. This will yield approximately 86% coverage of Mercury, leaving only the north and south polar regions yet to be imaged by MESSENGER after orbit insertion in March 2011. A new global mosaic of Mercury was constructed using 325 images containing 3566 control points (8110 measures) from M1 and 225 images containing 1465 control points (3506 measures) from M2. The M3 flyby is shifted in subsolar longitude only by 4° from M2, so the added coverage is very small. However, this small slice of Mercury fills a gore in the mosaic between the M1 and M2 data and allows a complete cartographic tie around the equator. We will run a new bundle block adjustment with the additional images acquired from M3. This new edition of the MESSENGER Mercury Dual Imaging System (MDIS) Narrow Angle Camera (NAC) global mosaic of Mercury includes many improvements since the M2 flyby in October 2008. A new distortion model for the NAC camera greatly improves the image-to-image registration. Optical distortion correction is independent of pointing error correction, and both are required for a mosaic of high quality. The new distortion model alone reduced residual pointing errors for both flybys significantly; residual pixel error improved from 0.71 average (3.7 max) to 0.13 average (1.7 max) for M1 and from 0.72 average (4.8 max.) to 0.17 average (3.5 max) for M2. Analysis quantifying pivot motor position has led to development of a new model that improves accuracy of the pivot platform attitude. This model improves the accuracy of pointing knowledge and reduces overall registration errors between adjacent images. The net effect of these improvements is an overall offset of up to 10 km in some locations across the mosaic. In addition, the radiometric calibration process for the NAC has been improved to yield a better dynamic range across the mosaic by 20%. The new global mosaic of Mercury will be used in scientific analysis and aid in planning observation sequences leading up to and including orbit insertion of the MESSENGER spacecraft in 2011.
Navigation of autonomous vehicles for oil spill cleaning in dynamic and uncertain environments
NASA Astrophysics Data System (ADS)
Jin, Xin; Ray, Asok
2014-04-01
In the context of oil spill cleaning by autonomous vehicles in dynamic and uncertain environments, this paper presents a multi-resolution algorithm that seamlessly integrates the concepts of local navigation and global navigation based on the sensory information; the objective here is to enable adaptive decision making and online replanning of vehicle paths. The proposed algorithm provides a complete coverage of the search area for clean-up of the oil spills and does not suffer from the problem of having local minima, which is commonly encountered in potential-field-based methods. The efficacy of the algorithm is tested on a high-fidelity player/stage simulator for oil spill cleaning in a harbour, where the underlying oil weathering process is modelled as 2D random-walk particle tracking. A preliminary version of this paper was presented by X. Jin and A. Ray as 'Coverage Control of Autonomous Vehicles for Oil Spill Cleaning in Dynamic and Uncertain Environments', Proceedings of the American Control Conference, Washington, DC, June 2013, pp. 2600-2605.
Jovian aurora from Juno perijove passes: comparison of ultraviolet and infrared images
NASA Astrophysics Data System (ADS)
Gérard, J.-C.; Bonfond, B.; Adriani, A.; Gladstone, G. R.; Mura, A.; Grodent, D.; Versteeg, M. H.; Greathouse, T. K.; Hue, V.; Altieri, F.; Dinelli, B. M.; Moriconi, M. L.; Migliorini, A.; Radioti, A.; Bolton, S. J.; Connerney, J. E. P.; Levin, S. M.; Fabiano, F.
2017-09-01
The electromagnetic radiation emitted by the Jovian aurora extends from the X-Rays presumably caused by heavy ion precipitation and electron bremsstrahlung to thermal infrared radiation resulting from enhanced heating by high-energy charged particles. Many observations have been made since the 1990s with the Hubble Space Telescope, which was able to image the H2 Lyman and Werner bands that are directly excited by collisions of auroral electrons with H2. Ground-based telescopes obtained spectra and images of the thermal H3+ emission produced by charge transfer between H2+ and H+ ions and neutral H2 molecules in the lower thermosphere. However, so far the geometry of the observations limited the coverage from Earth orbit and only one case of simultaneous UV and infrared emissions has been described in the literature. The Juno mission provides the unique advantage to observe both Jovian hemispheres simultaneously in the two wavelength regions simultaneously and offers a more global coverage with unprecedented spatial resolution. This was the case.
A closer look at temperature changes with remote sensing
NASA Astrophysics Data System (ADS)
Metz, Markus; Rocchini, Duccio; Neteler, Markus
2014-05-01
Temperature is a main driver for important ecological processes. Time series temperature data provide key environmental indicators for various applications and research fields. High spatial and temporal resolution is crucial in order to perform detailed analyses in various fields of research. While meteorological station data are commonly used, they often lack completeness or are not distributed in a representative way. Remotely sensed thermal images from polar orbiting satellites are considered to be a good alternative to the scarce meteorological data as they offer almost continuous coverage of the Earth with very high temporal resolution. A drawback of temperature data obtained by satellites is the occurrence of gaps (due to clouds, aerosols) that must be filled. We have reconstructed a seamless and gap-free time series for land surface temperature (LST) at continental scale for Europe from MODIS LST products (Moderate Resolution Imaging Sensor instruments onboard the Terra and Aqua satellites), keeping the temporal resolution of four records per day and enhancing the spatial resolution from 1 km to 250 m. Here we present a new procedure to reconstruct MODIS LST time series with unprecedented detail in space and time, at the same time providing continental coverage. Our method constitutes a unique new combination of weighted temporal averaging with statistical modeling and spatial interpolation. We selected as auxiliary variables datasets which are globally available in order to propose a worldwide reproducible method. Compared to existing similar datasets, the substantial quantitative difference translates to a qualitative difference in applications and results. We consider both our dataset and the new procedure for its creation to be of utmost interest to a broad interdisciplinary audience. Moreover, we provide examples for its implications and applications, such as disease risk assessment, epidemiology, environmental monitoring, and temperature anomalies. In the near future, aggregated derivatives of our dataset (following the BIOCLIM variable scheme) will be freely made online available for direct usage in GIS based applications.
Enhanced global seismic resolution using proposed undersea cables
NASA Astrophysics Data System (ADS)
Ranasinghe, N. R.; Rowe, C. A.; Larmat, C. S.; Syracuse, E. M.; Begnaud, M. L.
2016-12-01
With the exception of a few isolated, near-shore deployments of Ocean-bottom seismometers (OBS's), most seismic instrumentation on the Earth is located on land, although two thirds of the Earth's surface is covered with oceans. Most large earthquakes are unevenly distributed along the Earth's subduction zones; hence, large areas of the Earth are unevenly sampled in terms of seismic rays. The goal of this work is to produce a comparison of seismic ray coverage of the Earth with today's seismic stations to that which might be possible in the future if densely-instrumented transoceanic cables are deployed.Our work is motivated by the planning of a Joint Task Force under the UN that is proposing to integrate seismic sensors at intervals as small as 75 km along the next generation of oceanic telecommunication cables. These sensors offer the potential to improve global geophysical models as well as reduce event detection thresholds and location uncertainties in poorly characterized regions. Data coverage is first estimated via an infinite-frequency ray-tracing utility (Pcalc) that is used to predict seismic propagation in support of the United States effort towards nuclear explosion monitoring. We have predicted P-wave raypaths from 1668 earthquakes to 4421 seismic stations to produce global raypath density images in the crust and mantle. We present the improvement in ray coverage achieved at crustal and mantle depths by the addition of 1382 sensors along the telecommunication cables and we discuss the areas in which our models and earthquake characterization benefits from these proposed instruments. Because the Earth's complex 3D structure can have frequency-dependent effects on seismic propagation, we also employ a spectral element method (SPECFEM3D) to compute finite-frequency kernels that include the first order of scattering produced by 3D anomalies, and we present progress on this effort to compare with our infinite-frequency predictions.
Partisan differences in the relationship between newspaper coverage and concern over global warming.
Zhao, Xiaoquan; Rolfe-Redding, Justin; Kotcher, John E
2016-07-01
The effects of news media on public opinion about global warming have been a topic of much interest in both academic and popular discourse. Empirical evidence in this regard, however, is still limited and somewhat mixed. This study used data from the 2006 General Social Survey in combination with a content analysis of newspaper coverage of the same time period to examine the relationship between general news climate and public concern about global warming. Results showed a pattern of political polarization, with increased coverage associated with growing divergence between Democrats and Republicans. Further analysis also showed evidence of reactivity in partisan response to coverage from different news outlets. These findings point to a particular form of politically motivated, biased processing of news information. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Bovensmann, Heinrich; Buchwitz, M.; Burrows, J. P.; Notholt, J.; Bovensmann, H.; Reuter, M.; Trautmann, T.; Ehret, G.; Heimann, M.; Monks, P.; B&Ü, H.; Sch; Harding, R.; Quegan, S.; Rayner, P.; Breon, F. M.; Bergam-O Aschi, P.; Dittus, H. J.; Erzinger, J.; Crisp, D.
Surprisingly and in spite of their exceptional driving role in climate change, our knowledge about the variable sources and sinks of the greenhouse gases CO2 and CH4 is currently inadequate. For example, the ability of the Earth-atmosphere system to buffer increasing anthropogenic emissions into the atmosphere has large uncertainties and emissions from many sources (geo-logic, anthropogenic, biogenic) are to a large degree uncertain. An adequate knowledge of the sources and sinks of CO2 and CH4 and their response to a changing climate is a pre-requisite for the accurate prediction of the regional variation of the climate of our planet. CarbonSat is a new mission concept to quantify and monitor CO2 and CH4 sources and sinks at the regional to local scale. The data will allow a better understanding of the processes that control the Carbon Cycle dynamics and an independent estimate of local greenhouse gas emissions (fossil fuel, geological CO2 and CH4, etc.). This will be achieved by a unique combination of high spatial resolution passive and active compact remote sensing with inverse modeling techniques. CarbonSat will accurately measure column-averaged mixing ratios of CO2 and CH4, i.e., XCO2 and XCH4, at a spatial resolution of 2 x 2 km2 (500 km continuous swath) with 0.5 percent goal (1 percent threshold) single measurement precision and global coverage within 3-6 days. Beside the quantification of sources and sinks on the regional scale, one key and innovative aim of the CarbonSat mission is to go a step forward towards quantifying local emission hot spots (fossil fuel emissions by power plants, gas/oil production, geological sources etc.). The core sensor will be a compact Imaging NIR/SWIR spectrometer (SCIAMACHY, OCO her-itage) whose measurements yield global data sets of XCO2 and XCH4 with at least one order of magnitude higher number of cloud free measurements than GOSAT and OCO and one order of magnitude better spatial coverage than OCO, due to CarbonSat's 500 km swath continuous across track coverage with 2 x 2 km2 spatial resolution. Ideally, the imaging spectrometer will be accompanied by a compact CH4 Lidar, to derive complementary accurate XCH4 -especially in high northern latitudes -as well as information on clouds and vegetation height. The overall mission concept will be presented.
NASA Astrophysics Data System (ADS)
Bovensmann, Heinrich; Buchwitz, Michael
2010-05-01
Surprisingly and in spite of their exceptional driving role in climate change, our knowledge about the variable sources and sinks of the greenhouse gases CO2 and CH4 is currently inadequate. For example, the ability of the Earth-atmosphere system to buffer increasing anthropogenic emissions into the atmosphere has large uncertainties and emissions from many sources (geologic, anthropogenic, biogenic) are to a large degree uncertain. An adequate knowledge of the sources and sinks of CO2 and CH4 and their response to a changing climate is a pre-requisite for the accurate prediction of the regional variation of the climate of our planet. CarbonSat is a new mission concept to quantify and monitor CO2 and CH4 sources and sinks at the regional to local scale. The data will allow a better understanding of the processes that control the Carbon Cycle dynamics and an independent estimate of local greenhouse gas emissions (fossil fuel, geological CO2 and CH4, etc.). This will be achieved by a unique combination of high spatial resolution passive and active compact remote sensing with inverse modeling techniques. CarbonSat will accurately measure column-averaged mixing ratios of CO2 and CH4, i.e., XCO2 and XCH4, at a spatial resolution of 2 x 2 km2 (500 km continuous swath) with 0.5% goal (1%, threshold) single measurement precision and global coverage within 3-6 days. Beside the quantification of sources and sinks on the regional scale, one key and innovative aim of the CarbonSat mission is to go a step forward towards quantifying local emission hot spots (fossil fuel emissions by power plants, gas/oil production, geological sources etc.). The core sensor will be a compact Imaging NIR/SWIR spectrometer (SCIAMACHY, OCO heritage) whose measurements yield global data sets of XCO2 and XCH4 with at least one order of magnitude higher number of cloud free measurements than GOSAT and OCO and one order of magnitude better spatial coverage than OCO, due to CarbonSat's 500 km swath continuous across track coverage with 2 x 2 km2 spatial resolution. Ideally, the imaging spectrometer will be accompanied by a compact CH4 Lidar, to derive complementary accurate XCH4 - especially in high northern latitudes - as well as information on clouds and vegetation height. The overall mission concept, the expected data quality and selected application areas will be presented.
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM1_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM4_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-04-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM1_Edition1-CV)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM2_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM3_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_TRMM-PFM_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2000-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM4_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM3_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
Competition between plant functional types in the Canadian Terrestrial Ecosystem Model (CTEM) v. 2.0
NASA Astrophysics Data System (ADS)
Melton, J. R.; Arora, V. K.
2015-06-01
The Canadian Terrestrial Ecosystem Model (CTEM) is the interactive vegetation component in the Earth system model of the Canadian Centre for Climate Modelling and Analysis. CTEM models land-atmosphere exchange of CO2 through the response of carbon in living vegetation, and dead litter and soil pools, to changes in weather and climate at timescales of days to centuries. Version 1.0 of CTEM uses prescribed fractional coverage of plant functional types (PFTs) although, in reality, vegetation cover continually adapts to changes in climate, atmospheric composition, and anthropogenic forcing. Changes in the spatial distribution of vegetation occur on timescales of years to centuries as vegetation distributions inherently have inertia. Here, we present version 2.0 of CTEM which includes a representation of competition between PFTs based on a modified version of the Lotka-Volterra (L-V) predator-prey equations. Our approach is used to dynamically simulate the fractional coverage of CTEM's seven natural, non-crop PFTs which are then compared with available observation-based estimates. Results from CTEM v. 2.0 show the model is able to represent the broad spatial distributions of its seven PFTs at the global scale. However, differences remain between modelled and observation-based fractional coverages of PFTs since representing the multitude of plant species globally, with just seven non-crop PFTs, only captures the large scale climatic controls on PFT distributions. As expected, PFTs that exist in climate niches are difficult to represent either due to the coarse spatial resolution of the model, and the corresponding driving climate, or the limited number of PFTs used. We also simulate the fractional coverages of PFTs using unmodified L-V equations to illustrate its limitations. The geographic and zonal distributions of primary terrestrial carbon pools and fluxes from the versions of CTEM that use prescribed and dynamically simulated fractional coverage of PFTs compare reasonably well with each other and observation-based estimates. The parametrization of competition between PFTs in CTEM v. 2.0 based on the modified L-V equations behaves in a reasonably realistic manner and yields a tool with which to investigate the changes in spatial distribution of vegetation in response to future changes in climate.
Competition between plant functional types in the Canadian Terrestrial Ecosystem Model (CTEM) v. 2.0
NASA Astrophysics Data System (ADS)
Melton, J. R.; Arora, V. K.
2016-01-01
The Canadian Terrestrial Ecosystem Model (CTEM) is the interactive vegetation component in the Earth system model of the Canadian Centre for Climate Modelling and Analysis. CTEM models land-atmosphere exchange of CO2 through the response of carbon in living vegetation, and dead litter and soil pools, to changes in weather and climate at timescales of days to centuries. Version 1.0 of CTEM uses prescribed fractional coverage of plant functional types (PFTs) although, in reality, vegetation cover continually adapts to changes in climate, atmospheric composition and anthropogenic forcing. Changes in the spatial distribution of vegetation occur on timescales of years to centuries as vegetation distributions inherently have inertia. Here, we present version 2.0 of CTEM, which includes a representation of competition between PFTs based on a modified version of the Lotka-Volterra (L-V) predator-prey equations. Our approach is used to dynamically simulate the fractional coverage of CTEM's seven natural, non-crop PFTs, which are then compared with available observation-based estimates. Results from CTEM v. 2.0 show the model is able to represent the broad spatial distributions of its seven PFTs at the global scale. However, differences remain between modelled and observation-based fractional coverage of PFTs since representing the multitude of plant species globally, with just seven non-crop PFTs, only captures the large-scale climatic controls on PFT distributions. As expected, PFTs that exist in climate niches are difficult to represent either due to the coarse spatial resolution of the model, and the corresponding driving climate, or the limited number of PFTs used. We also simulate the fractional coverage of PFTs using unmodified L-V equations to illustrate its limitations. The geographic and zonal distributions of primary terrestrial carbon pools and fluxes from the versions of CTEM that use prescribed and dynamically simulated fractional coverage of PFTs compare reasonably well with each other and observation-based estimates. The parametrization of competition between PFTs in CTEM v. 2.0 based on the modified L-V equations behaves in a reasonably realistic manner and yields a tool with which to investigate the changes in spatial distribution of vegetation in response to future changes in climate.
Guo, Yi; Lebel, R Marc; Zhu, Yinghua; Lingala, Sajan Goud; Shiroishi, Mark S; Law, Meng; Nayak, Krishna
2016-05-01
To clinically evaluate a highly accelerated T1-weighted dynamic contrast-enhanced (DCE) MRI technique that provides high spatial resolution and whole-brain coverage via undersampling and constrained reconstruction with multiple sparsity constraints. Conventional (rate-2 SENSE) and experimental DCE-MRI (rate-30) scans were performed 20 minutes apart in 15 brain tumor patients. The conventional clinical DCE-MRI had voxel dimensions 0.9 × 1.3 × 7.0 mm(3), FOV 22 × 22 × 4.2 cm(3), and the experimental DCE-MRI had voxel dimensions 0.9 × 0.9 × 1.9 mm(3), and broader coverage 22 × 22 × 19 cm(3). Temporal resolution was 5 s for both protocols. Time-resolved images and blood-brain barrier permeability maps were qualitatively evaluated by two radiologists. The experimental DCE-MRI scans showed no loss of qualitative information in any of the cases, while achieving substantially higher spatial resolution and whole-brain spatial coverage. Average qualitative scores (from 0 to 3) were 2.1 for the experimental scans and 1.1 for the conventional clinical scans. The proposed DCE-MRI approach provides clinically superior image quality with higher spatial resolution and coverage than currently available approaches. These advantages may allow comprehensive permeability mapping in the brain, which is especially valuable in the setting of large lesions or multiple lesions spread throughout the brain.
Future U.S. ocean color missions-OCI, MODIS and HIRIS
NASA Astrophysics Data System (ADS)
Davis, C. O.
The Coastal Zone Color Scanner (CZCS) launched by the National Aeronautics and Space Administration (NASA) on the Nimbus-7 Satellite in 1978 has provided exceptionally valuable data for studies of the productivity of the ocean, fisheries, the detection of oceanic fronts and currents, and the optical properties of the ocean. NASA has been working with the scientific community, the National Oceanographic and Atmospheric Administration (NOAA), France's Centre National d'Etudes Spatiales (CNES), and industry to develop an Ocean Color Imager (OCI), a follow-on instrument which would provide the near real-time and global data necessary to fill these needs in the 1990's. The Earth Observing Satellite Company (EOSAT) is considering flying an ocean and land wide-field color instrument which would meet these needs on Landsat 6 or 7 planned for launch in 1989 and 1991, respectively. It would provide eight ocean color channels for improved atmospheric correction and in-water algorithms, global coverage and near real-time data for operational uses. In the mid 1990's NASA is planning to fly a Moderate Resolution Imaging Spectrometer (MODIS) and a High Resolution Imaging Spectrometer (HIRIS) as part of the Earth Observing System (Eos) on the Polar Platform of the Space Station. These instruments are array spectrometers which would provide full spectral resolution in the visible and infrared. This opens the possibility of separating different groups of phytoplankton, suspended sediments and other substances in the water. Also, HIRIS would have across track pointing ability which will allow high resolution rapid sampling of dynamic coastal areas and estuaries.
NASA Astrophysics Data System (ADS)
Parker, H. A.; Hedelius, J.; Viatte, C.; Wunch, D.; Wennberg, P. O.; Chen, J.; Wofsy, S.; Jones, T.; Franklin, J.; Dubey, M. K.; Roehl, C. M.; Podolske, J. R.; Hillyard, P. W.; Iraci, L. T.
2015-12-01
Measurement, reporting and verification (MRV) of anthropogenic emissions and natural sources and sinks of carbon dioxide (CO2) and methane (CH4) are crucial to predict climate change and develop transparent accounting policies to contain climate forcing. Remote sensing technologies are monitoring column averaged dry air mole fractions of CO2 and CH4 (XCO2 & XCH4) from ground and space (OCO-2 and GOSAT) with solar spectroscopy enabling direct MRV. However, current ground based coverage is sparse due to the need for large and expensive high-resolution spectrometers that are part of the Total Column Carbon Observing Network (TCCON, Bruker 125HR). This limits our MRV and satellite validation abilities, both regionally and globally. There are striking monitoring gaps in Asia, South America and Africa where the CO2 emissions are growing and there is a large uncertainty in fluxes from land use change, biomass burning and rainforest vulnerability. To fill this gap we evaluate the precision, accuracy and stability of compact, affordable and easy to use low-resolution spectrometers (Bruker EM27/SUN) by comparing with XCO2 and XCH4 retrieved from much larger high-resolution TCCON instruments. As these instruments will be used in a variety of locations, we evaluate their performance by comparing with 2 previous and 4 current United States TCCON sites in different regions up to 2700 km apart. These sites range from polluted to unpolluted, latitudes of 32 to 46°N, and altitudes of 230 to 2241 masl. Comparisons with some of these sites cover multiple years allowing assessment of the EM27/SUN performance not only in various regions, but also over an extended period of time and with different seasonal influences. Results show that our 2 EM27/SUN instruments capture the diurnal variability of the aforementioned constituents very well, but with offsets from TCCON and long-term variability which may be due in part to the extensive movement these spectrometers were subjected to. These off-the-shelf spectrometers should dramatically expand the coverage of regional XCO2 and XCH4 observations, particularly in gap regions. Increased temporal and spacial resolution on global carbon data will lead to more reliable information when considering climate change policy and funding.
2015-10-09
This global digital map of Saturn's moon Titan was created using images taken by NASA's Cassini spacecraft's imaging science subsystem (ISS). The map was produced in June 2015 using data collected through Cassini's flyby on April 7, 2014, known as "T100." The images were taken using a filter centered at 938 nanometers, allowing researchers to examine variations in albedo (or inherent brightness) across the surface of Titan. Because of the scattering of light by Titan's dense atmosphere, no topographic shading is visible in these images. The map is an equidistant projection and has a scale of 2.5 miles (4 kilometers) per pixel. Actual resolution varies greatly across the map, with the best coverage (close to the map scale) along the equator near the center of the map at 180 degrees west longitude. The lowest resolution coverage can be seen in the northern mid-latitudes on the sub-Saturn hemisphere. Mapping coverage in the northern polar region has greatly improved since the previous version of this map in 2011 (see PIA14908). Large dark areas, now known to be liquid-hydrocarbon-filled lakes and seas, have since been documented at high latitudes. Titan's north pole was not well illuminated early in Cassini's mission, because it was winter in the northern hemisphere when the spacecraft arrived at Saturn. Cassini has been better able to observe northern latitudes in more recent years due to seasonal changes in solar illumination. This map is an update to the previous versions released in April 2011 and February 2009 (see PIA11149). Data from the past four years (the most recent data in the map is from April 2014) has completely filled in missing data in the north polar region and replaces the earlier imagery of the Xanadu region with higher quality data. A data gap of about 3 to 5 percent of Titan's surface still remains, located in the northern mid-latitudes on the sub-Saturn hemisphere of Titan. The uniform gray area in the northern hemisphere indicates a gap in the imaging coverage of Titan's surface, to date. The missing data will be imaged by Cassini during flybys on December 15, 2016 and March 5, 2017. The mean radius of Titan used for projection of this map is 1,600 miles (2,575 kilometers). Titan is assumed to be spherical until a control network -- a model of the moon's shape based on multiple images tied together at defined points on the surface -- is created at some point in the future. http://photojournal.jpl.nasa.gov/catalog/PIA19658
Effects of finite coverage on global polarization observables in heavy ion collisions
NASA Astrophysics Data System (ADS)
Lan, Shaowei; Lin, Zi-Wei; Shi, Shusu; Sun, Xu
2018-05-01
In non-central relativistic heavy ion collisions, the created matter possesses a large initial orbital angular momentum. Particles produced in the collisions could be polarized globally in the direction of the orbital angular momentum due to spin-orbit coupling. Recently, the STAR experiment has presented polarization signals for Λ hyperons and possible spin alignment signals for ϕ mesons. Here we discuss the effects of finite coverage on these observables. The results from a multi-phase transport and a toy model both indicate that a pseudorapidity coverage narrower than | η | < ∼ 1 will generate a larger value for the extracted ϕ-meson ρ00 parameter; thus a finite coverage can lead to an artificial deviation of ρ00 from 1/3. We also show that a finite η and pT coverage affect the extracted pH parameter for Λ hyperons when the real pH value is non-zero. Therefore proper corrections are necessary to reliably quantify the global polarization with experimental observables.
Global lunar-surface mapping experiment using the Lunar Imager/Spectrometer on SELENE
NASA Astrophysics Data System (ADS)
Haruyama, Junichi; Matsunaga, Tsuneo; Ohtake, Makiko; Morota, Tomokatsu; Honda, Chikatoshi; Yokota, Yasuhiro; Torii, Masaya; Ogawa, Yoshiko
2008-04-01
The Moon is the nearest celestial body to the Earth. Understanding the Moon is the most important issue confronting geosciences and planetary sciences. Japan will launch the lunar polar orbiter SELENE (Kaguya) (Kato et al., 2007) in 2007 as the first mission of the Japanese long-term lunar exploration program and acquire data for scientific knowledge and possible utilization of the Moon. An optical sensing instrument called the Lunar Imager/Spectrometer (LISM) is loaded on SELENE. The LISM requirements for the SELENE project are intended to provide high-resolution digital imagery and spectroscopic data for the entire lunar surface, acquiring these data for scientific knowledge and possible utilization of the Moon. Actually, LISM was designed to include three specialized sub-instruments: a terrain camera (TC), a multi-band imager (MI), and a spectral profiler (SP). The TC is a high-resolution stereo camera with 10-m spatial resolution from a SELENE nominal altitude of 100 km and a stereo angle of 30° to provide stereo pairs from which digital terrain models (DTMs) with a height resolution of 20 m or better will be produced. The MI is a multi-spectral imager with four and five color bands with 20 m and 60 m spatial resolution in visible and near-infrared ranges, which will provide data to be used to distinguish the geological units in detail. The SP is a line spectral profiler with a 400-m-wide footprint and 300 spectral bands with 6-8 nm spectral resolution in the visible to near-infrared ranges. The SP data will be sufficiently powerful to identify the lunar surface's mineral composition. Moreover, LISM will provide data with a spatial resolution, signal-to-noise ratio, and covered spectral range superior to that of past Earth-based and spacecraft-based observations. In addition to the hardware instrumentation, we have studied operation plans for global data acquisition within the limited total data volume allotment per day. Results show that the TC and MI can achieve global observations within the restrictions by sharing the TC and MI observation periods, adopting appropriate data compression, and executing necessary SELENE orbital plane change operations to ensure global coverage by MI. Pre-launch operation planning has resulted in possible global TC high-contrast imagery, TC stereoscopic imagery, and MI 9-band imagery in one nominal mission period. The SP will also acquire spectral line profiling data for nearly the entire lunar surface. The east-west interval of the SP strip data will be 3-4 km at the equator by the end of the mission and shorter at higher latitudes. We have proposed execution of SELENE roll cant operations three times during the nominal mission period to execute calibration site observations, and have reached agreement on this matter with the SELENE project. We present LISM global surface mapping experiments for instrumentation and operation plans. The ground processing systems and the data release plan for LISM data are discussed briefly.
Imaging During MESSENGER's Second Flyby of Mercury
NASA Astrophysics Data System (ADS)
Chabot, N. L.; Prockter, L. M.; Murchie, S. L.; Robinson, M. S.; Laslo, N. R.; Kang, H. K.; Hawkins, S. E.; Vaughan, R. M.; Head, J. W.; Solomon, S. C.; MESSENGER Team
2008-12-01
During MESSENGER's second flyby of Mercury on October 6, 2008, the Mercury Dual Imaging System (MDIS) will acquire 1287 images. The images will include coverage of about 30% of Mercury's surface not previously seen by spacecraft. A portion of the newly imaged terrain will be viewed during the inbound portion of the flyby. On the outbound leg, MDIS will image additional previously unseen terrain as well as regions imaged under different illumination geometry by Mariner 10. These new images, when combined with images from Mariner 10 and from MESSENGER's first Mercury flyby, will enable the first regional- resolution global view of Mercury constituting a combined total coverage of about 96% of the planet's surface. MDIS consists of both a Wide Angle Camera (WAC) and a Narrow Angle Camera (NAC). During MESSENGER's second Mercury flyby, the following imaging activities are planned: about 86 minutes before the spacecraft's closest pass by the planet, the WAC will acquire images through 11 different narrow-band color filters of the approaching crescent planet at a resolution of about 5 km/pixel. At slightly less than 1 hour to closest approach, the NAC will acquire a 4-column x 11-row mosaic with an approximate resolution of 450 m/pixel. At 8 minutes after closest approach, the WAC will obtain the highest-resolution multispectral images to date of Mercury's surface, imaging a portion of the surface through 11 color filters at resolutions of about 250-600 m/pixel. A strip of high-resolution NAC images, with a resolution of approximately 100 m/pixel, will follow these WAC observations. The NAC will next acquire a 15-column x 13- row high-resolution mosaic of the northern hemisphere of the departing planet, beginning approximately 21 minutes after closest approach, with resolutions of 140-300 m/pixel; this mosaic will fill a large gore in the Mariner 10 data. At about 42 minutes following closest approach, the WAC will acquire a 3x3, 11-filter, full- planet mosaic with an average resolution of 2.5 km/pixel. Two NAC mosaics of the entire departing planet will be acquired beginning about 66 minutes after closest approach, with resolutions of 500-700 m/pixel. About 89 minutes following closest approach, the WAC will acquire a multispectral image set with a resolution of about 5 km/pixel. Following this WAC image set, MDIS will continue to acquire occasional images with both the WAC and NAC until 20 hours after closest approach, at which time the flyby data will begin being transmitted to Earth.
NASA Astrophysics Data System (ADS)
Lee, C. M.; Omar, A. H.; Hook, S. J.; Tzortziou, M.; Luvall, J. C.; Turner, W. W.
2016-02-01
Observations from the Pre-Aerosol Cloud and ocean Ecosystem (PACE) and Hyperspectral InfraRed Imager (HyspIRI) satellite missions are highly complementary and have the potential to significantly advance understanding of various science and applications challenges in the ocean sciences and water quality communities. Scheduled for launch in the 2022 timeframe, PACE is designed to make climate-quality global measurements essential for understanding ocean biology, biogeochemistry and ecology, and determining the role of the ocean in global biogeochemical cycling and ocean ecology, and how it affects and is affected by climate change. PACE will provide high signal-to-noise, hyperspectral observations over an extended spectral range (UV to SWIR) and will have global coverage every 1-2 days, at approximately 1 km spatial resolution; furthermore, PACE is currently designed to include a polarimeter, which will vastly improve atmospheric correction algorithms over water bodies. The PACE mission will enable advances in applications across a range of areas, including oceans, climate, water resources, ecological forecasting, disasters, human health and air quality. HyspIRI, with contiguous measurements in VSWIR, and multispectral measurements in TIR, will be able to provide detailed spectral observations and higher spatial resolution (30 to 60-m) over aquatic systems, but at a temporal resolution that is approximately 5-16 days. HyspIRI would enable improved, detailed studies of aquatic ecosystems, including benthic communities, algal blooms, coral reefs, and wetland species distribution as well as studies of water quality indicators or pollutants such as oil spills, suspended sediment, and colored dissolved organic matter. Together, PACE and HyspIRI will be able to address numerous applications and science priorities, including improving and extending climate data records, and studies of inland, coastal and ocean environments.
Lu, Chunling; Michaud, Catherine M; Gakidou, Emmanuela; Khan, Kashif; Murray, Christopher J L
2006-09-23
The Global Alliance for Vaccines and Immunisation (GAVI) was created in 1999 to enable even the poorest countries to provide vaccines to all children. We aimed to assess the effect of GAVI on combined diphtheria, tetanus, and pertussis vaccine (DTP3) coverage. We examined the relation between DTP3 coverage for GAVI recipient countries from 1995 to 2004 and immunisation services support (ISS) and non-ISS expenditure per surviving child, controlling for income per head and local political governance variables. We analysed DTP3 coverage reported by governments and estimated by WHO/UNICEF. We also investigated the effect of GAVI on country reporting behaviour. In countries with DTP3 coverage of 65% or less at baseline, ISS spending per surviving child had a significant positive effect on DTP3 coverage (p=0.0005). This effect was not present in countries with DTP3 coverage of 65-80% or 80% or more at baseline. If ISS expenditure only is assessed, the estimated cost per additional child immunised in countries with baseline coverage of 65% or less is US$14 and if ISS and non-ISS expenditures are included the cost per child is almost $20. The success of ISS funding in countries with baseline DTP3 coverage of 65% or less provides evidence that a public-private partnership can work to reverse a negative trend in global health and that performance-related disbursement can work in some settings. Because ISS funding seems to have no effect in countries with baseline coverage greater than 65%, GAVI should consider redistributing its resources to countries with the lowest coverage.
Diffusion impact on atmospheric moisture transport
NASA Astrophysics Data System (ADS)
Moseley, C.; Haerter, J.; Göttel, H.; Hagemann, S.; Jacob, D.
2009-04-01
To ensure numerical stability, many global and regional climate models employ numerical diffusion to dampen short wavelength modes. Terrain following sigma diffusion is known to cause unphysical effects near the surface in orographically structured regions. They can be reduced by applying z-diffusion on geopotential height levels. We investigate the effect of the diffusion scheme on atmospheric moisture transport and precipitation formation at different resolutions in the European region. With respect to a better understanding of diffusion in current and future grid-space global models, current day regional models may serve as the appropriate tool for studies of the impact of diffusion schemes: Results can easily be constrained to a small test region and checked against reliable observations, which often are unavailable on a global scale. Special attention is drawn to the Alps - a region of strong topographic gradients and good observational coverage. Our study is further motivated by the appearance of the "summer drying problem" in South Eastern Europe. This too warm and too dry simulation of climate is common to many regional climate models and also to some global climate models, and remains a permanent unsolved problem in the community. We perform a systematic comparison of the two diffusion-schemes with respect to the hydrological cycle. In particular, we investigate how local meteorological quantities - such as the atmospheric moisture in the region east of the Alps - depend on the spatial model resolution. Higher model resolution would lead to a more accurate representation of the topography and entail larger gradients in the Alps. This could lead to consecutively stronger transport of moisture along the slopes in the case of sigma-diffusion with subsequent orographic precipitation, whereas the effect could be qualitatively different in the case of z-diffusion. For our study, we analyse a sequence of simulations of the regional climate model REMO employing the different diffusion methods over Europe. For these simulations, REMO was forced at the lateral boundaries with ERA40 reanalysis data for a five year period. For our higher resolution simulations we employ the double nesting technique.
The Tectonics of Mercury: The View from Orbit
NASA Astrophysics Data System (ADS)
Watters, T. R.; Byrne, P. K.; Klimczak, C.; Enns, A. C.; Banks, M. E.; Walsh, L. S.; Ernst, C. M.; Robinson, M. S.; Gillis-Davis, J. J.; Solomon, S. C.; Strom, R. G.; Gwinner, K.
2011-12-01
Flybys of Mercury by the Mariner 10 and MESSENGER spacecraft revealed a broad distribution of contractional tectonic landforms, including lobate scarps, high-relief ridges, and wrinkle ridges. Among these, lobate scarps were seen as the dominant features and have been interpreted as having formed as a result of global contraction in response to interior cooling. Extensional troughs and graben, where identified, were generally confined to intermediate- to large-scale impact basins. However, the true global spatial distribution of tectonic landforms remained poorly defined because the flyby observations were limited in coverage and spatial resolution, and many flyby images were obtained under lighting geometries far from ideal for the detection and identification of morphologic features. With the successful insertion of MESSENGER into orbit in March 2011, we are exploiting the opportunity to characterize the tectonics of Mercury in unprecedented detail using images at high resolution and optimum lighting, together with topographic data obtained from Mercury Laser Altimeter (MLA) profiles and stereo imaging. We are digitizing all of Mercury's major tectonic landforms in a standard geographic information system format from controlled global monochrome mosaics (mean resolution 250 m/px), complemented by high-resolution targeted images (up to ~10 m/px), obtained by the Mercury Dual Imaging System (MDIS) cameras. On the basis of an explicit set of diagnostic criteria, we are mapping wrinkle ridges, high-relief ridges, lobate scarps, and extensional troughs and graben in separate shapefiles and cataloguing the segment endpoint positions, length, and orientation for each landform. The versatility of digital mapping facilitates the merging of this tectonic information with other MESSENGER-derived map products, e.g., volcanic units, surface color, geochemical variations, topography, and gravity. Results of this mapping work to date include the identification of extensional features in the northern plains and elsewhere on Mercury in the form of troughs, which commonly form polygonal patterns, in some two dozen volcanically flooded impact craters and basins.
NASA Astrophysics Data System (ADS)
Zhang, Tianran; Wooster, Martin
2016-04-01
Until recently, crop residues have been the second largest industrial waste product produced in China and field-based burning of crop residues is considered to remain extremely widespread, with impacts on air quality and potential negative effects on health, public transportation. However, due to the small size and perhaps short-lived nature of the individual burns, the extent of the activity and its spatial variability remains somewhat unclear. Satellite EO data has been used to gauge the timing and magnitude of Chinese crop burning, but current approaches very likely miss significant amounts of the activity because the individual burned areas are either too small to detect with frequently acquired moderate spatial resolution data such as MODIS. The Visible Infrared Imaging Radiometer Suite (VIIRS) on-board Suomi-NPP (National Polar-orbiting Partnership) satellite launched on October, 2011 has one set of multi-spectral channels providing full global coverage at 375 m nadir spatial resolutions. It is expected that the 375 m spatial resolution "I-band" imagery provided by VIIRS will allow active fires to be detected that are ~ 10× smaller than those that can be detected by MODIS. In this study the new small fire detection algorithm is built based on VIIRS-I band global fire detection algorithm and hot spot detection algorithm for the BIRD satellite mission. VIIRS-I band imagery data will be used to identify agricultural fire activity across Eastern China. A 30 m spatial resolution global land cover data map is used for false alarm masking. The ground-based validation is performed using images taken from UAV. The fire detection result is been compared with active fire product from the long-standing MODIS sensor onboard the TERRA and AQUA satellites, which shows small fires missed from traditional MODIS fire product may count for over 1/3 of total fire energy in Eastern China.
NASA Astrophysics Data System (ADS)
Haley, Craig Stuart
2009-12-01
Key to understanding and predicting the effects of global environmental problems such as ozone depletion and global warming is a detailed understanding of the atmospheric processes, both dynamical and chemical. Essential to this understanding are accurate global data sets of atmospheric constituents with adequate temporal and spatial (vertical and horizontal) resolutions. For this purpose the Canadian satellite instrument OSIRIS (Optical Spectrograph and Infrared Imager System) was launched on the Odin satellite in 2001. OSIRIS is primarily designed to measure minor stratospheric constituents, including ozone (O3) and nitrogen dioxide (NO2), employing the novel limb-scattered sunlight technique, which can provide both good vertical resolution and near global coverage. This dissertation presents a method to retrieve stratospheric O 3 and NO2 from the OSIRIS limb-scatter observations. The retrieval method incorporates an a posteriori optimal estimator combined with an intermediate spectral analysis, specifically differential optical absorption spectroscopy (DOAS). A detailed description of the retrieval method is presented along with the results of a thorough error analysis and a geophysical validation exercise. It is shown that OSIRIS limb-scatter observations successfully produce accurate stratospheric O3 and NO2 number density profiles throughout the stratosphere, clearly demonstrating the strength of the limb-scatter technique. The OSIRIS observations provide an extremely useful data set that is of particular importance for studies of the chemistry of the middle atmosphere. The long OSIRIS record of stratospheric ozone and nitrogen dioxide may also prove useful for investigating variability and trends.
Wallace, Aaron S.; Ryman, Tove K.; Dietz, Vance
2015-01-01
Background Review of the historical growth in annual vaccination coverage across countries and regions can better inform decision makers’ development of future goals and strategies to improve routine vaccination services. Methods Using the World Health Organization (WHO) and the United Nations Children's Fund estimates of annual national third dose of diphtheria-tetanus-pertussis–containing vaccine (DTP3) and third dose of polio vaccine (POL3) coverage for 1980–2009, we calculated the mean absolute annual rate of change in national DTP3 coverage among all countries (globally) and among countries within each WHO region, as well as the number of years taken by each region to reach specific regional coverage levels. Last, we assessed differences in mean absolute annual rate of change in DTP3 coverage, stratified by baseline level of DTP3 coverage. Results During the 1980s, global DTP3 coverage increased a mean of 5.3 percentage points/year. Annual rate of change decreased to 0.5 percentage points/year in the 1990s and then increased to 0.9 percentage points/year during the 2000s. Mean annual rate of change in coverage across all countries was highest (9.2 percentage points) when national coverage levels were 26%–30% and lowest (−0.9 percentage points) when national coverage levels were 96%–100%. Regional differences existed as both WHO South-East Asia Region and WHO African Region countries experienced mean negative DTP3 coverage growth at lower coverage levels (81%–85%) than other regions. The regions that have achieved 95% DTP3 coverage (Americas, Western Pacific, and European) took 25–29 years to reach that level from a level of 50% DTP3 coverage. POL3 coverage change trends were similar to described DTP3 coverage change trends. Conclusions Mean national coverage growth patterns across all regions are nonlinear as coverage levels increase. Saturation points of mean 0 percentage-point growth in annual coverage varies by region and require further investigation. The achievement of >90% routine coverage is observed to take decades, which has implications for disease eradication and elimination initiatives. PMID:25316875
On requirements for a satellite mission to measure tropical rainfall
NASA Technical Reports Server (NTRS)
Thiele, Otto W. (Editor)
1987-01-01
Tropical rainfall data are crucial in determining the role of tropical latent heating in driving the circulation of the global atmosphere. Also, the data are particularly important for testing the realism of climate models, and their ability to simulate and predict climate accurately on the seasonal time scale. Other scientific issues such as the effects of El Nino on climate could be addressed with a reliable, extended time series of tropical rainfall observations. A passive microwave sensor is planned to provide information on the integrated column precipitation content, its areal distribution, and its intensity. An active microwave sensor (radar) will define the layer depth of the precipitation and provide information about the intensity of rain reaching the surface, the key to determining the latent heat input to the atmosphere. A visible/infrared sensor will provide very high resolution information on cloud coverage, type, and top temperatures and also serve as the link between these data and the long and virtually continuous coverage by the geosynchronous meteorological satellites. The unique combination of sensor wavelengths, coverages, and resolving capabilities together with the low-altitude, non-Sun synchronous orbit provide a sampling capability that should yield monthly precipitation amounts to a reasonable accuracy over a 500- by 500-km grid.
Swath sonar mapping of Earth's submarine plate boundaries
NASA Astrophysics Data System (ADS)
Carbotte, S. M.; Ferrini, V. L.; Celnick, M.; Nitsche, F. O.; Ryan, W. B. F.
2014-12-01
The recent loss of Malaysia Airlines flight MH370 in an area of the Indian Ocean where less than 5% of the seafloor is mapped with depth sounding data (Smith and Marks, EOS 2014) highlights the striking lack of detailed knowledge of the topography of the seabed for much of the worlds' oceans. Advances in swath sonar mapping technology over the past 30 years have led to dramatic improvements in our capability to map the seabed. However, the oceans are vast and only an estimated 10% of the seafloor has been mapped with these systems. Furthermore, the available coverage is highly heterogeneous and focused within areas of national strategic priority and community scientific interest. The major plate boundaries that encircle the globe, most of which are located in the submarine environment, have been a significant focus of marine geoscience research since the advent of swath sonar mapping. While the location of these plate boundaries are well defined from satellite-derived bathymetry, significant regions remain unmapped at the high-resolutions provided by swath sonars and that are needed to study active volcanic and tectonic plate boundary processes. Within the plate interiors, some fossil plate boundary zones, major hotspot volcanoes, and other volcanic provinces have been the focus of dedicated research programs. Away from these major tectonic structures, swath mapping coverage is limited to sparse ocean transit lines which often reveal previously unknown deep-sea channels and other little studied sedimentary structures not resolvable in existing low-resolution global compilations, highlighting the value of these data even in the tectonically quiet plate interiors. Here, we give an overview of multibeam swath sonar mapping of the major plate boundaries of the globe as extracted from public archives. Significant quantities of swath sonar data acquired from deep-sea regions are in restricted-access international archives. Open access to more of these data sets would enable global comparisons of plate boundary structures and processes and could facilitate a more coordinated approach to optimizing the future acquisition of these high-value data by the global research community.
Snow Coverage Analysis Using ASTER over the Sierra Nevada Mountain Range
NASA Astrophysics Data System (ADS)
Ross, B.
2017-12-01
Snow has strong impacts on human behavior, state and local activities, and the economy. The Sierra Nevada snowpack is California's most important natural reservoir of water. Such snow is melting sooner and faster. A recent California drought study showed that there was a deficit of 1.5 million acre-feet of water in 2014 due to the fast melting rates. Scientists have been using the Moderate Resolution Imaging Spectrometer (MODIS) which is available at the spatial resolution of 500-meter, to analyze the changes in snow coverage. While such analysis provides us with the valuable information, it would be more beneficial to employ the imageries at a higher spatial resolution for snow studies. Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER), which acquires the high-resolution imageries ranging from 15-meter to 90-meter, has recently become freely available to the public. Our study utilized two scenes obtained from ASTER to investigate the changes in snow extent over the Sierra Nevada's mountain area for an 8-year period. These two scenes were collected on April 11, 2007 and April 16, 2015 covering the same geographic region. Normalized Difference Snow Index (NDSI) was adopted to delineate the snow coverage in each scene. Our study shows a substantial decrease of snow coverage in the studied geographic region by pixel count.
NASA Astrophysics Data System (ADS)
Berg, W. K.
2016-12-01
The Global Precipitation Mission (GPM) Core Observatory, which was launched in February of 2014, provides a number of advances for satellite monitoring of precipitation including a dual-frequency radar, high frequency channels on the GPM Microwave Imager (GMI), and coverage over middle and high latitudes. The GPM concept, however, is about producing unified precipitation retrievals from a constellation of microwave radiometers to provide approximately 3-hourly global sampling. This involves intercalibration of the input brightness temperatures from the constellation radiometers, development of an apriori precipitation database using observations from the state-of-the-art GPM radiometer and radars, and accounting for sensor differences in the retrieval algorithm in a physically-consistent way. Efforts by the GPM inter-satellite calibration working group, or XCAL team, and the radiometer algorithm team to create unified precipitation retrievals from the GPM radiometer constellation were fully implemented into the current version 4 GPM precipitation products. These include precipitation estimates from a total of seven conical-scanning and six cross-track scanning radiometers as well as high spatial and temporal resolution global level 3 gridded products. Work is now underway to extend this unified constellation-based approach to the combined TRMM/GPM data record starting in late 1997. The goal is to create a long-term global precipitation dataset employing these state-of-the-art calibration and retrieval algorithm approaches. This new long-term global precipitation dataset will incorporate the physics provided by the combined GPM GMI and DPR sensors into the apriori database, extend prior TRMM constellation observations to high latitudes, and expand the available TRMM precipitation data to the full constellation of available conical and cross-track scanning radiometers. This combined TRMM/GPM precipitation data record will thus provide a high-quality high-temporal resolution global dataset for use in a wide variety of weather and climate research applications.
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES4_TRMM-PFM_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=1998-08-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_PFM+FM1_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_FM1+FM4_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Terra-FM2_Edition1-CV)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2006-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Aqua-FM3_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Aqua-FM3_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Aqua-FM4_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_FM1+FM2_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2003-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Terra-FM1_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Aqua-FM4_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Aqua-FM4_Edition1-CV)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Terra-FM2_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_Terra-FM1_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-10-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_PFM+FM2_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_FM1+FM2_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2002-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
CERES ERBE-like Monthly Geographical Averages (ES-4) in HDF (CER_ES4_FM1+FM3_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ERBE-like Monthly Geographical Averages (ES-4) product contains a month of space and time averaged Clouds and the Earth's Radiant Energy System (CERES) data for a single scanner instrument. The ES-4 is also produced for combinations of scanner instruments. For each observed 2.5-degree spatial region, the daily average, the hourly average over the month, and the overall monthly average of shortwave and longwave fluxes at the Top-of-the-Atmosphere (TOA) from the CERES ES-9 product are spatially nested up from 2.5-degree regions to 5- and 10-degree regions, to 2.5-, 5-, and 10-degree zonal averages, and to global monthly averages. For each nested area, the albedo and net flux are given. For each region, the daily average flux is estimated from an algorithm that uses the available hourly data, scene identification data, and diurnal models. This algorithm is 'like' the algorithm used for the Earth Radiation Budget Experiment (ERBE). The following CERES ES4 data sets are currently available: CER_ES4_FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition1 CER_ES4_PFM+FM1+FM2_Edition2 CER_ES4_PFM+FM1_Edition1 CER_ES4_PFM+FM2_Edition1 CER_ES4_TRMM-PFM_Edition1 CER_ES4_TRMM-PFM_Edition2 CER_ES4_Terra-FM1_Edition1 CER_ES4_Terra-FM2_Edition1 CER_ES4_FM1+FM2_Edition2 CER_ES4_Terra-FM1_Edition2 CER_ES4_Terra-FM2_Edition2 CER_ES4_Aqua-FM3_Edition1 CER_ES4_Aqua-FM4_Edition1 CER_ES4_FM1+FM2+FM3+FM4_Edition1 CER_ES4_Aqua-FM3_Edition2 CER_ES4_Aqua-FM4_Edition2 CER_ES4_FM1+FM3_Edition2 CER_ES4_FM1+FM4_Edition2 CER_ES4_PFM+FM1_Edition2 CER_ES4_PFM+FM2_Edition2 CER_ES4_Aqua-FM3_Edition1-CV CER_ES4_Aqua-FM4_Edition1-CV CER_ES4_Terra-FM1_Edition1-CV CER_ES4_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1998-01-01; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=2.5 degree; Longitude_Resolution=2.5 degree; Horizontal_Resolution_Range=250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees; Temporal_Resolution=1 month; Temporal_Resolution_Range=Monthly - < Annual].
Troc: a proposed tropospheric sounder for chemistry and climate
NASA Astrophysics Data System (ADS)
Camy-Peyret, C.
TROC has been submitted to ESA in the last call for proposals of the Earth Explorer Opportunity Missions and its focus is on tropospheric composition and chemistry-climate interactions. The mission objectives of TROC cover four research subjects. Global tropospheric chemistry: perform global measurements from space of tropospheric composition in order to improve our understanding and to constrain models of tropospheric chemistry with emphasis on tropospheric ozone. Pollution: establish the impact of mega cities of industrialised or developing countries by monitoring their pollution plumes. Biomass burning: monitor the chemical species and aerosols injected in the free troposphere during major burning episodes in the intertropical region as well as by major forest fires at other latitudes. Chemistry-climate interactions: quantify on a global scale the distributions and the sources of greenhouse gases like CO2, CH4, O3, N2O and the CFCs. Contribute to demonstration studies for monitoring from space how Montreal and Kyoto protocols are enforced as far as human impacts on atmospheric chemistry and climate are concerned. To fulfil these objectives, passive remote sensing of the troposphere has been selected as the best compromise between technical maturity and multi-species coverage. The main elements of TROC are a Fourier transform infrared (FTIR) instrument and an ultraviolet-visible (UV-vis) spectrometer, both operating in the downward-looking geometry with a 10 km diameter footprint at nadir. An ``intelligent'' pointing mirror coupled to an infrared imager is used to optimise day/night sounding down to the surface. The FTIR instrument covers at 0.1 cm-1 apodised spectral resolution 3 bands from 14 to 3.3 μ m in thermal emission and one band in solar reflected light around 2.3 μ m. The UV-vis instrument covers the regions 290-490 nm (1 nm resolution) and 520-1030 nm (2.5 nm resolution) with 43 array detectors (2 bands × 2 polarizations) in reflected/backscattered sunlight. The diurnal/nocturnal cycle is sampled with a non-sun synchronous circular orbit of 728 km altitude and 65 inclination. Global coverage between 68N and 68S is ensured by a swath of 800 km (11 pixels) and at least one clear pixel in every 100 km × 100 km area is revisited every 3 days. TROC will provide tropospheric profiles for O3, CO and CH4 (3 independent pieces of information in the troposphere) as well as total and tropospheric columns for NO2, H2CO, SO2, BrO and C2H6 together with height resolved information on tropospheric aerosols. Information on other species (H2O, CO2, N2O, CFCs, OCS, ldots) of importance for climate studies will also be obtained. The scientific/technical aspects and status of this project will be presented.
NASA Astrophysics Data System (ADS)
Barrera-Verdejo, María; Crewell, Susanne; Löhnert, Ulrich; Orlandi, Emiliano; Di Girolamo, Paolo
2016-08-01
Continuous monitoring of atmospheric humidity profiles is important for many applications, e.g., assessment of atmospheric stability and cloud formation. Nowadays there are a wide variety of ground-based sensors for atmospheric humidity profiling. Unfortunately there is no single instrument able to provide a measurement with complete vertical coverage, high vertical and temporal resolution and good performance under all weather conditions, simultaneously. For example, Raman lidar (RL) measurements can provide water vapor with a high vertical resolution, albeit with limited vertical coverage, due to sunlight contamination and the presence of clouds. Microwave radiometers (MWRs) receive water vapor information throughout the troposphere, though their vertical resolution is poor. In this work, we present an MWR and RL system synergy, which aims to overcome the specific sensor limitations. The retrieval algorithm combining these two instruments is an optimal estimation method (OEM), which allows for an uncertainty analysis of the retrieved profiles. The OEM combines measurements and a priori information, taking the uncertainty of both into account. The measurement vector consists of a set of MWR brightness temperatures and RL water vapor profiles. The method is applied to a 2-month field campaign around Jülich (Germany), focusing on clear sky periods. Different experiments are performed to analyze the improvements achieved via the synergy compared to the individual retrievals. When applying the combined retrieval, on average the theoretically determined absolute humidity uncertainty is reduced above the last usable lidar range by a factor of ˜ 2 with respect to the case where only RL measurements are used. The analysis in terms of degrees of freedom per signal reveal that most information is gained above the usable lidar range, especially important during daytime when the lidar vertical coverage is limited. The retrieved profiles are further evaluated using radiosounding and Global Position Satellite (GPS) water vapor measurements. In general, the benefit of the sensor combination is especially strong in regions where Raman lidar data are not available (i.e., blind regions, regions characterized by low signal-to-noise ratio), whereas if both instruments are available, RL dominates the retrieval. In the future, the method will be extended to cloudy conditions, when the impact of the MWR becomes stronger.
Stable Satellite Orbits for Global Coverage of the Moon
NASA Technical Reports Server (NTRS)
Ely, Todd; Lieb, Erica
2006-01-01
A document proposes a constellation of spacecraft to be placed in orbit around the Moon to provide navigation and communication services with global coverage required for exploration of the Moon. There would be six spacecraft in inclined elliptical orbits: three in each of two orthogonal orbital planes, suggestive of a linked-chain configuration. The orbits have been chosen to (1) provide 99.999-percent global coverage for ten years and (2) to be stable under perturbation by Earth gravitation and solar-radiation pressure, so that no deterministic firing of thrusters would be needed to maintain the orbits. However, a minor amount of orbit control might be needed to correct for such unmodeled effects as outgassing of the spacecraft.
Dynamics of the Antarctic Circumpolar Current as seen by GRACE (Invited)
NASA Astrophysics Data System (ADS)
Thomas, M.; Dobslaw, H.; Bergmann, I.
2010-12-01
The Antarctic Circumpolar Current, being the strongest and longest ocean current on Earth, connects the three great ocean basins and contributes substantially to the global re-distribution of water masses, with a significant impact on global climate. Observational coverage from in-situ measurements is sparse due to the harsh environmental conditions, and satellite altimetry does not capture the full extent of the current due to seasonal sea-ice coverage. Ocean bottom pressure variations as sensed with the satellite gravity mission GRACE provide a promising way to broaden our observational basis. Besides monthly mean gravity fields that provide ocean bottom pressure variations averaged over 30 days, several alternative GRACE products with higher temporal resolution have been developed during the most recent years. These include 10-day solutions from GRGS Toulouse, weekly solutions from the GFZ Potsdam as well as constrained daily solutions from the University of Bonn which have been obtained by means of a Kalman filtering approach. In this presentation, ocean bottom pressure derived from these alternative GRACE releases will be contrasted against both in-situ observations and output from a numerical ocean model, highlighting the additional information contained in these GRACE solutions with respect to the standard monthly fields. By means of statistical analyses of ocean bottom pressure variations and barotropic transports it will be demonstrated how these new GRACE releases are contributing to our understanding of this highly dynamic great ocean conveyor.
NASA Astrophysics Data System (ADS)
Shen, S. S.
2014-12-01
This presentation describes a suite of global precipitation products reconstructed by a multivariate regression method using an empirical orthogonal function (EOF) expansion. The sampling errors of the reconstruction are estimated for each product datum entry. The maximum temporal coverage is 1850-present and the spatial coverage is quasi-global (75S, 75N). The temporal resolution ranges from 5-day, monthly, to seasonal and annual. The Global Precipitation Climatology Project (GPCP) precipitation data from 1979-2008 are used to calculate the EOFs. The Global Historical Climatology Network (GHCN) gridded data are used to calculate the regression coefficients for reconstructions. The sampling errors of the reconstruction are analyzed in detail for different EOF modes. Our reconstructed 1900-2011 time series of the global average annual precipitation shows a 0.024 (mm/day)/100a trend, which is very close to the trend derived from the mean of 25 models of the CMIP5 (Coupled Model Intercomparison Project Phase 5). Our reconstruction examples of 1983 El Niño precipitation and 1917 La Niña precipitation (Figure 1) demonstrate that the El Niño and La Niña precipitation patterns are well reflected in the first two EOFs. The validation of our reconstruction results with GPCP makes it possible to use the reconstruction as the benchmark data for climate models. This will help the climate modeling community to improve model precipitation mechanisms and reduce the systematic difference between observed global precipitation, which hovers at around 2.7 mm/day for reconstructions and GPCP, and model precipitations, which have a range of 2.6-3.3 mm/day for CMIP5. Our precipitation products are publically available online, including digital data, precipitation animations, computer codes, readme files, and the user manual. This work is a joint effort between San Diego State University (Sam Shen, Nancy Tafolla, Barbara Sperberg, and Melanie Thorn) and University of Maryland (Phil Arkin, Tom Smith, Li Ren, and Li Dai) and supported in part by the U.S. National Science Foundation (Awards No. AGS-1015926 and AGS-1015957).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Yi, E-mail: yiguo@usc.edu; Zhu, Yinghua; Lingala, Sajan Goud
Purpose: To clinically evaluate a highly accelerated T1-weighted dynamic contrast-enhanced (DCE) MRI technique that provides high spatial resolution and whole-brain coverage via undersampling and constrained reconstruction with multiple sparsity constraints. Methods: Conventional (rate-2 SENSE) and experimental DCE-MRI (rate-30) scans were performed 20 minutes apart in 15 brain tumor patients. The conventional clinical DCE-MRI had voxel dimensions 0.9 × 1.3 × 7.0 mm{sup 3}, FOV 22 × 22 × 4.2 cm{sup 3}, and the experimental DCE-MRI had voxel dimensions 0.9 × 0.9 × 1.9 mm{sup 3}, and broader coverage 22 × 22 × 19 cm{sup 3}. Temporal resolution was 5 smore » for both protocols. Time-resolved images and blood–brain barrier permeability maps were qualitatively evaluated by two radiologists. Results: The experimental DCE-MRI scans showed no loss of qualitative information in any of the cases, while achieving substantially higher spatial resolution and whole-brain spatial coverage. Average qualitative scores (from 0 to 3) were 2.1 for the experimental scans and 1.1 for the conventional clinical scans. Conclusions: The proposed DCE-MRI approach provides clinically superior image quality with higher spatial resolution and coverage than currently available approaches. These advantages may allow comprehensive permeability mapping in the brain, which is especially valuable in the setting of large lesions or multiple lesions spread throughout the brain.« less
LDCM Ground System. Network Lesson Learned
NASA Technical Reports Server (NTRS)
Gal-Edd, Jonathan
2010-01-01
This slide presentation reviews the Landsat Data Continuity Mission (LDCM) and the lessons learned in implementing the network that was assembled to allow for the acquisition, archiving and distribution of the data from the Landsat mission. The objective of the LDCM is to continue the acquisition, archiving, and distribution of moderate-resolution multispectral imagery affording global, synoptic, and repetitive coverage of the earth's land surface at a scale where natural and human-induced changes can be detected, differentiated, characterized, and monitored over time. It includes a review of the ground network, including a block diagram of the ground network elements (GNE) and a review of the RF design and testing. Also included is a listing of the lessons learned.
Riometer based Neural Network Prediction of Kp
NASA Astrophysics Data System (ADS)
Arnason, K. M.; Spanswick, E.; Chaddock, D.; Tabrizi, A. F.; Behjat, L.
2017-12-01
The Canadian Geospace Observatory Riometer Array is a network of 11 wide-beam riometers deployed across Central and Northern Canada. The geographic coverage of the network affords a near continent scale view of high energy (>30keV) electron precipitation at a very course spatial resolution. In this paper we present the first results from a neural network based analysis of riometer data. Trained on decades of riometer data, the neural network is tuned to predict a simple index of global geomagnetic activity (Kp) based solely on the information provided by the high energy electron precipitation over Canada. We present results from various configurations of training and discuss the applicability of this technique for short term prediction of geomagnetic activity.
Haider, Adil; Scott, John W; Gause, Colin D; Meheš, Mira; Hsiung, Grace; Prelvukaj, Albulena; Yanocha, Dana; Baumann, Lauren M; Ahmed, Faheem; Ahmed, Na'eem; Anderson, Sara; Angate, Herve; Arfaa, Lisa; Asbun, Horacio; Ashengo, Tigistu; Asuman, Kisembo; Ayala, Ruben; Bickler, Stephen; Billingsley, Saul; Bird, Peter; Botman, Matthijs; Butler, Marilyn; Buyske, Jo; Capozzi, Angelo; Casey, Kathleen; Clayton, Charles; Cobey, James; Cotton, Michael; Deckelbaum, Dan; Derbew, Miliard; deVries, Catherine; Dillner, Jeanne; Downham, Max; Draisin, Natalie; Echinard, David; Elneil, Sohier; ElSayed, Ahmed; Estelle, Abigail; Finley, Allen; Frenkel, Erica; Frykman, Philip K; Gheorghe, Florin; Gore-Booth, Julian; Henker, Richard; Henry, Jaymie; Henry, Orion; Hoemeke, Laura; Hoffman, David; Ibanga, Iko; Jackson, Eric V; Jani, Pankaj; Johnson, Walter; Jones, Andrew; Kassem, Zeina; Kisembo, Asuman; Kocan, Abbey; Krishnaswami, Sanjay; Lane, Robert; Latif, Asad; Levy, Barbara; Linos, Dimitrios; Linz, Peter; Listwa, Louis A; Magee, Declan; Makasa, Emmanuel; Marin, Michael L; Martin, Claude; McQueen, Kelly; Morgan, Jamie; Moser, Richard; Neighbor, Robert; Novick, William M; Ogendo, Stephen; Omigbodun, Akinyinka; Onajin-Obembe, Bisola; Parsan, Neil; Philip, Beverly K; Price, Raymond; Rasheed, Shahnawaz; Ratel, Marjorie; Reynolds, Cheri; Roser, Steven M; Rowles, Jackie; Samad, Lubna; Sampson, John; Sanghvi, Harshadkumar; Sellers, Marchelle L; Sigalet, David; Steffes, Bruce C; Stieber, Erin; Swaroop, Mamta; Tarpley, John; Varghese, Asha; Varughese, Julie; Wagner, Richard; Warf, Benjamin; Wetzig, Neil; Williamson, Susan; Wood, Joshua; Zeidan, Anne; Zirkle, Lewis; Allen, Brendan; Abdullah, Fizan
2017-10-01
After decades on the margins of primary health care, surgical and anaesthesia care is gaining increasing priority within the global development arena. The 2015 publications of the Disease Control Priorities third edition on Essential Surgery and the Lancet Commission on Global Surgery created a compelling evidenced-based argument for the fundamental role of surgery and anaesthesia within cost-effective health systems strengthening global strategy. The launch of the Global Alliance for Surgical, Obstetric, Trauma, and Anaesthesia Care in 2015 has further coordinated efforts to build priority for surgical care and anaesthesia. These combined efforts culminated in the approval of a World Health Assembly resolution recognizing the role of surgical care and anaesthesia as part of universal health coverage. Momentum gained from these milestones highlights the need to identify consensus goals, targets and indicators to guide policy implementation and track progress at the national level. Through an open consultative process that incorporated input from stakeholders from around the globe, a global target calling for safe surgical and anaesthesia care for 80% of the world by 2030 was proposed. In order to achieve this target, we also propose 15 consensus indicators that build on existing surgical systems metrics and expand the ability to prioritize surgical systems strengthening around the world.
NASA Astrophysics Data System (ADS)
Mouffe, Melodie; Getirana, Augusto; Ricci, Sophie; Lion, Christine; Biancamaria, Sylvian; Boone, Aaron; Mognard, Nelly; Rogel, Philippe
2013-09-01
The Surface Water and Ocean Topography (SWOT) wide swath altimetry mission will provide measurements of water surface elevations (WSE) at a global scale. The aim of this study is to investigate the potential of these satellite data for the calibration of the hydrological model HyMAP, over the Amazon river basin. Since SWOT has not yet been launched, synthetical observations are used to calibrate the river bed depth and width, the Manning coefficient and the baseflow concentration time. The calibration process stands in the minimization of a cost function using an evolutionnary, global and multi-objective algorithm that describes the difference between the simulated and the observed WSE. We found that the calibration procedure is able to retrieve an optimal set of parameters such that it brings the simulated WSE closer to the observation. Still with a global calibration procedure where a uniform correction is applied, the improvement is limited to a mean correction over the catchment and the simulation period. We conclude that in order to benefit from the high resolution and complete coverage of the SWOT mission, the calibration process should be achieved sequentially in time over sub-domains as observations become available.
High-resolution global irradiance monitoring from photovoltaic systems
NASA Astrophysics Data System (ADS)
Buchmann, Tina; Pfeilsticker, Klaus; Siegmund, Alexander; Meilinger, Stefanie; Mayer, Bernhard; Pinitz, Sven; Steinbrecht, Wolfgang
2016-04-01
Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition. To achieve this goal our studies introduce a novel method which makes use of photovoltaic power generation in order to infer global irradiance. The method allows to determine high-resolution temporal global irradiance data (one data point every 15 minutes at each location) from power data of operated photovoltaic systems. Due to the multitude of installed photovoltaic systems (in Germany) the detailed spatial coverage is much better than for example only using global irradiance data from conventional pyranometer networks (e.g. from the German Weather Service). Our designated method is composed of two components: a forward component, i.e. to conclude from predicted global irradiance to photovoltaic (PV) power, and a backward component, i.e. from PV power with suitable calibration to global irradiance. The forward process is modelled by using the radiation transport model libRadtran (B. Mayer and A. Kylling (1)) for clear skies to obtain the characteristics (orientation, size, temperature dependence, …) of individual PV systems. For PV systems in the vicinity of a meteorological station, these data are validated against calibrated pyranometer readings. The forward-modelled global irradiance is used to determine the power efficiency for each photovoltaic system using non-linear optimisation techniques. The backward component uses the power efficiency and meteorological parameters (e.g. from the model COSMO-DE) to calculate global irradiance by means of the generated power of individual photovoltaic systems. For the year 2012, our method is tested for PV systems in the Allgäu region (south Germany), the distribution area of the system operator "AllgäuNetz GmbH & Co". The test region includes 215 online-monitored photovoltaic systems and one pyranometer station located at the DWD (Deutscher WetterDienst) weather station Hohenpeißenberg (operated by the German Weather Service). The present talk provides an introduction to the newly developed method along with first results for clear sky scenarios. (1) B. Mayer and A. Kylling (2005): Technical note: The libRadtran software package for radiative transfer calculations - description and examples of use. In: Chemistry and Physics Chemistry and Physics. Page: 1855 - 1877
NASA Astrophysics Data System (ADS)
Kraft, S.; Del Bello, U.; Drusch, M.; Gabriele, A.; Harnisch, B.; Moreno, J.
2013-09-01
Vegetation fluorescence when measured from space contributes only a tiny fraction of the signal coming on top of the reflected radiance by the Earth surface and the atmosphere. As a consequence, imaging spectrometers have to provide sufficient throughput and radiometric accuracy to enable accurate global monitoring of the daily to seasonal variations of the Earth's vegetation breath, which is particularly challenging if ground resolutions of a few hundred meters are targeted. Since fluorescence retrieval algorithms have to make corrections for atmospheric effects, it is necessary to provide sufficient spectral resolution, so that signal alterations due to the main parameters such as surface pressure, atmospheric temperature profile, vertical distribution of aerosols concentration, and water vapour content can be accurately modelled. ESA's Earth Explorer 8 candidate mission FLEX carries a Fluorescence Imaging Spectrometer (FLORIS), which has been designed and optimised to enable such measurement. The spectrometer will measure in a spectral range between 500 and 780 nm and provide high spectral resolution of 0.3 nm in particular at the Oxygen-A and -B bands. It will also cover the photochemical reflection features between 500 and 600 nm, the Chlorophyll absorption region between 600 and 677 nm, and the red-edge in the region of 697 to 755 nm. FLEX will fly in formation with Sentinel-3 in order to further enhance the spectral coverage from measurements made by the Sentinel-3 instruments OLCI and SLSTR, particularly for cloud screening and proper characterization of the atmospheric status.
NASA Astrophysics Data System (ADS)
Hu, H.; Wu, B.
2017-07-01
The Narrow-Angle Camera (NAC) on board the Lunar Reconnaissance Orbiter (LRO) comprises of a pair of closely attached high-resolution push-broom sensors, in order to improve the swath coverage. However, the two image sensors do not share the same lenses and cannot be modelled geometrically using a single physical model. Thus, previous works on dense matching of stereo pairs of NAC images would generally create two to four stereo models, each with an irregular and overlapping region of varying size. Semi-Global Matching (SGM) is a well-known dense matching method and has been widely used for image-based 3D surface reconstruction. SGM is a global matching algorithm relying on global inference in a larger context rather than individual pixels to establish stable correspondences. The stereo configuration of LRO NAC images causes severe problem for image matching methods such as SGM, which emphasizes global matching strategy. Aiming at using SGM for image matching of LRO NAC stereo pairs for precision 3D surface reconstruction, this paper presents a coupled epipolar rectification methods for LRO NAC stereo images, which merges the image pair in the disparity space and in this way, only one stereo model will be estimated. For a stereo pair (four) of NAC images, the method starts with the boresight calibration by finding correspondence in the small overlapping stripe between each pair of NAC images and bundle adjustment of the stereo pair, in order to clean the vertical disparities. Then, the dominate direction of the images are estimated by project the center of the coverage area to the reference image and back-projected to the bounding box plane determined by the image orientation parameters iteratively. The dominate direction will determine an affine model, by which the pair of NAC images are warped onto the object space with a given ground resolution and in the meantime, a mask is produced indicating the owner of each pixel. SGM is then used to generate a disparity map for the stereo pair and each correspondence is transformed back to the owner and 3D points are derived through photogrammetric space intersection. Experimental results reveal that the proposed method is able to reduce gaps and inconsistencies caused by the inaccurate boresight offsets between the two NAC cameras and the irregular overlapping regions, and finally generate precise and consistent 3D surface models from the NAC stereo images automatically.
Cloud properties inferred from 8-12 micron data
NASA Technical Reports Server (NTRS)
Strabala, Kathleen I.; Ackerman, Steven A.; Menzel, W. Paul
1994-01-01
A trispectral combination of observations at 8-, 11-, and 12-micron bands is suggested for detecting cloud and cloud properties in the infrared. Atmospheric ice and water vapor absorption peak in opposite halves of the window region so that positive 8-minus-11-micron brightness temperature differences indicate cloud, while near-zero or negative differences indicate clear regions. The absorption coefficient for water increases more between 11 and 12 microns than between 8 and 11 microns, while for ice, the reverse is true. Cloud phases is determined by a scatter diagram of 8-minus-11-micron versus 11-minus-12-micron brightness temperature differences; ice cloud shows a slope greater than 1 and water cloud less than 1. The trispectral brightness temperature method was tested upon high-resolution interferometer data resulting in clear-cloud and cloud-phase delineation. Simulations using differing 8-micron bandwidths revealed no significant degradation of cloud property detection. Thus, the 8-micron bandwidth for future satellites can be selected based on the requirements of other applications, such as surface characterization studies. Application of the technique to current polar-orbiting High-Resolution Infrared Sounder (HIRS)-Advanced Very High Resolution Radiometer (AVHRR) datasets is constrained by the nonuniformity of the cloud scenes sensed within the large HIRS field of view. Analysis of MAS (MODIS Airborne Simulator) high-spatial resolution (500 m) data with all three 8-, 11-, and 12-micron bands revealed sharp delineation of differing cloud and background scenes, from which a simple automated threshold technique was developed. Cloud phase, clear-sky, and qualitative differences in cloud emissivity and cloud height were identified on a case study segment from 24 November 1991, consistent with the scene. More rigorous techniques would allow further cloud parameter clarification. The opportunities for global cloud delineation with the Moderate-Resolution Imaging Spectrometer (MODIS) appear excellent. The spectral selection, the spatial resolution, and the global coverage are all well suited for significant advances.
Impact of CYGNSS Data on Tropical Cyclone Analyses and Forecasts in a Regional OSSE Framework
NASA Astrophysics Data System (ADS)
Annane, B.; McNoldy, B. D.; Leidner, S. M.; Atlas, R. M.; Hoffman, R.; Majumdar, S.
2016-12-01
The Cyclone Global Navigation Satellite System, or CYGNSS, is a planned constellation of micro-satellites that will utilize reflected Global Positioning System (GPS) satellite signals to retrieve ocean surface wind speed along the satellites' ground tracks. The orbits are designed so that there is excellent coverage of the tropics and subtropics, resulting in more thorough spatial sampling and improved sampling intervals over tropical cyclones than is possible with current spaceborne scatterometer and passive microwave sensor platforms. Furthermore, CYGNSS will be able to retrieve winds under all precipitating conditions, and over a large range of wind speeds.A regional Observing System Simulation Experiment (OSSE) framework was developed at NOAA/AOML and University of Miami that features a high-resolution regional nature run (27-km regional domain with 9/3/1 km storm-following nests; Nolan et al., 2013) embedded within a lower-resolution global nature run . Simulated observations are generated by sampling from the nature run and are provided to a data assimilation scheme, which produces analyses for a high-resolution regional forecast model, the 2014 operational Hurricane-WRF model. For data assimilation, NOAA's GSI and EnKF systems are used. Analyses are performed on the parent domain at 9-km resolution. The forecast model uses a single storm-following 3-km resolution nest. Synthetic CYGNSS wind speed data have also been created, and the impacts of the assimilation of these data on the forecasts of tropical cyclone track and intensity will be discussed.In addition to the choice of assimilation scheme, we have also examined a number of other factors/parameters that effect the impact of simulated CYGNSS observations, including frequency of data assimilation cycling (e.g., hourly, 3-hourly and 6-hourly) and the assimilation of scalar versus vector synthetic CYGNSS winds.We have found sensitivity to all of the factors tested and will summarize the methods used for testing as well as results. Generally, we have found that more frequent cycling is better than less; and flow-dependent background error covariances (e.g., EnKF) are better than static or climatological assumptions about the background error covariance.
NASA Astrophysics Data System (ADS)
1994-07-01
Satellites have shrunk the world to the size of the proverbial global village. They track weather and the traffic patterns of ships and aircraft, and monitor our environment. Defense satellites provide high-resolution images of objects on the ground to protect our troops and allies. Telecommunication satellites have interwoven business sectors, corporations, and markets into global networks. Nevertheless, orbiting satellites may not be the best choice for all applications requiring a high vantage point. satellites and their payloads are expensive, and launching them by rocket is expensive and risky. They must operate in the extreme conditions of space, bombarded by radiation and with no airflow to cool their electronics. Only valuable, long-term missions would seem to justify the expense and risk of a satellite. Even then, satellites are not always the best choice. They typically cannot hop to a new orbit, and some uses, such as local and global communications, require a large number of satellites to ensure adequate coverage. There is clearly a large potential role for high-altitude, atmospheric vehicles that can stay aloft for very long periods (weeks or months) and can roam virtually anywhere.
Progress and challenges in global mantle attenuation tomography (Invited)
NASA Astrophysics Data System (ADS)
Romanowicz, B. A.
2009-12-01
Global anelastic tomography has lagged behind elastic tomography, because of the difficulty to separate elastic and anelastic effects accumulated in the amplitudes of seismic waves as they propagate long distances through the heterogeneous mantle. Specifically, amplitudes are very sensitive to scattering and lateral gradients in elastic structure. Until now, these gradients - or the short wavelength features of elastic models - have not been tightly enough constrained due to a combination of (1) use of approximate wave propagation theories; (2) necessary damping due to incomplete coverage and bandwidth. Different schemes have been designed to circumvent these shortcomings in attenuation tomography, which limit resolution to long wavelengths and introduce large uncertainties in the estimation of the strength of lateral variations in attenuation. We review the robust information on anelastic structure available so far from first and second generation global upper mantle models. We discuss improvements that can be expected with, in particular, the availability of accurate numerical schemes for wave propagation in a 3D elastic earth, as well as the associated challenges, and prospects for unraveling the 3D attenuation structure of the lower mantle.
NASA Astrophysics Data System (ADS)
Boyer, T.; Locarnini, R. A.; Mishonov, A. V.; Reagan, J. R.; Seidov, D.; Zweng, M.; Levitus, S.
2017-12-01
Ocean heat uptake is the major factor in sequestering the Earth's Energy Imbalance (EEI). Since 2000, the National Centers for Environmental Information (NCEI) have been estimating historical ocean heat content (OHC) changes back to the 1950s, as well as monitoring recent OHC. Over these years, through worldwide community efforts, methods of calculating OHC have substantially improved. Similarly, estimation of the uncertainty of ocean heat content calculations provide new insight into how well EEI estimates can be constrained using in situ measurements and models. The changing ocean observing system, especially with the near-global year-round coverage afforded by Argo, has also allowed more confidence in regional and global OHC estimates and provided a benchmark for better understanding of historical OHC changes. NCEI is incorporating knowledge gained through these global efforts into the basic methods, instrument bias corrections, uncertainty measurements, and temporal and spatial resolution capabilities of historic OHC change estimation and recent monitoring. The nature of these improvements and their consequences for estimation of OHC in relation to the EEI will be discussed.
NASA Technical Reports Server (NTRS)
Head, J. W.; Belton, M.; Greeley, R.; Pieters, C.; Mcewen, A.; Neukum, G.; Mccord, T.
1993-01-01
The Lunar Scout Missions (payload: x-ray fluorescence spectrometer, high-resolution stereocamera, neutron spectrometer, gamma-ray spectrometer, imaging spectrometer, gravity experiment) will provide a global data set for the chemistry, mineralogy, geology, topography, and gravity of the Moon. These data will in turn provide an important baseline for the further scientific exploration of the Moon by all-purpose landers and micro-rovers, and sample return missions from sites shown to be of primary interest from the global orbital data. These data would clearly provide the basis for intelligent selection of sites for the establishment of lunar base sites for long-term scientific and resource exploration and engineering studies. The two recent Galileo encounters with the Moon (December, 1990 and December, 1992) illustrate how modern technology can be applied to significant lunar problems. We emphasize the regional results of the Galileo SSI to show the promise of geologic unit definition and characterization as an example of what can be done with the global coverage to be obtained by the Lunar Scout Missions.
Solar Data | Geospatial Data Science | NREL
System Name: WGS_1984 Coverage File Last Updated Metadata KMZ File Lower 48 and Hawaii DNI 10-km Resolution 1998-2009 Zip 9.6 MB 09/12/2012 Direct Normal.xml Direct Normal.kmz Lower 48 and Hawaii GHI 10-km : GCS_North_American_1983 Coverage File Last Updated Metadata KMZ File Lower 48 DNI 10-km Resolution 1998-2005 Zip 9.1 MB 12
AirMSPI ORACLES Terrain Data V006
Atmospheric Science Data Center
2018-05-05
... ER-2 Instrument: AirMSPI Spatial Coverage: United States, California, Georgia, Africa, Southern Africa, ... 10/25 meters per pixel Temporal Coverage: 07/28/2016 - 10/06/2016 Temporal Resolution: ...
Sentinel-3 coverage-driven mission design: Coupling of orbit selection and instrument design
NASA Astrophysics Data System (ADS)
Cornara, S.; Pirondini, F.; Palmade, J. L.
2017-11-01
The first satellite of the Sentinel-3 series was launched in February 2016. Sentinel-3 payload suite encompasses the Ocean and Land Colour Instrument (OLCI) with a swath of 1270 km, the Sea and Land Surface Temperature Radiometer (SLSTR) yielding a dual-view scan with swaths of 1420 km (nadir) and 750 km (oblique view), the Synthetic Aperture Radar Altimeter (SRAL) working in Ku-band and C-band, and the dual-frequency Microwave Radiometer (MWR). In the early stages of mission and system design, the main driver for the Sentinel-3 reference orbit selection was the requirement to achieve a revisit time of two days or less globally over ocean areas with two satellites (i.e. 4-day global coverage with one satellite). The orbit selection was seamlessly coupled with the OLCI instrument design in terms of field of view (FoV) definition driven by the observation zenith angle (OZA) and sunglint constraints applied to ocean observations. The criticality of the global coverage requirement for ocean monitoring derives from the sunglint phenomenon, i.e. the impact on visible channels of the solar ray reflection on the water surface. This constraint was finally overcome thanks to the concurrent optimisation of the orbit parameters, notably the Local Time at Descending Node (LTDN), and the OLCI instrument FoV definition. The orbit selection process started with the identification of orbits with short repeat cycle (2-4 days), firstly to minimise the time required to achieve global coverage with existing constraints, and then to minimise the swath required to obtain global coverage and the maximum required OZA. This step yielded the selection of a 4-day repeat cycle orbit, thus allowing 2-day coverage with two adequately spaced satellites. Then suitable candidate orbits with higher repeat cycles were identified in the proximity of the selected altitudes and the reference orbit was ultimately chosen. Rationale was to keep the swath for global coverage as close as possible to the previous optimum value, but to tailor the repeat cycle length (i.e. the ground-track grid) to optimise the topography mission performances. The final choice converged on the sun-synchronous orbit 14 + 7/27, reference altitude ∼800 km, LTDN = 10h00. Extensive coverage analyses were carried out to characterise the mission performance and the fulfilment of the requirements, encompassing revisit time, number of acquisitions, observation viewing geometry and swath properties. This paper presents a comprehensive overview of the Sentinel-3 orbit selection, starting from coverage requirements and highlighting the close interaction with the instrument design activity.
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Terra-FM1_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Terra-FM1_Edition1-CV)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-09-30] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Aqua-FM4_Edition1-CV)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Terra-FM2_Edition1)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_TRMM-PFM_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2000-03-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Aqua-FM3_Edition2)
NASA Technical Reports Server (NTRS)
Wielicki, Bruce A. (Principal Investigator)
The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-12-31] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].
NASA Technical Reports Server (NTRS)
Moody, E. G.; King, M. D.; Platnick, S.; Schaaf, C. B.; Gao, F.
2004-01-01
Spectral land surface albedo is an important parameter for describing the radiative properties of the Earth. Accordingly it reflects the consequences of natural and human interactions, such as anthropogenic, meteorological, and phenological effects, on global and local climatological trends. Consequently, albedos are integral parts in a variety of research areas, such as general circulation models (GCMs), energy balance studies, modeling of land use and land use change, and biophysical, oceanographic, and meteorological studies. The availability of global albedo data over a large range of spectral channels and at high spatial resolution has dramatically improved with the launch of the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA s Earth Observing System (EOS) Terra spacecraft in December 1999. However, lack of spatial and temporal coverage due to cloud and snow effects can preclude utilization of official products in production and research studies. We report on a technique used to fill incomplete MOD43 albedo data sets with the intention of providing complete value-added maps. The technique is influenced by the phenological concept that within a certain area, a pixel s ecosystem class should exhibit similar growth cycle events over the same time period. The shape of an area s phenological temporal curve can be imposed upon existing pixel-level data to fill missing temporal points. The methodology will be reviewed by showcasing 2001 global and regional results of complete albedo and NDVl data sets.
Sentinel-1A - Launching the first satellite and launching the operational Copernicus programme
NASA Astrophysics Data System (ADS)
Aschbacher, Josef; Milagro Perez, Maria Pilar
2014-05-01
The first Copernicus satellite, Sentinel-1A, is prepared for launch in April 2014. It will provide continuous, systematic and highly reliable radar images of the Earth. Sentinel-1B will follow around 18 months later to increase observation frequency and establish an operational system. Sentinel-1 is designed to work in a pre-programmed conflict-free operation mode ensuring the reliability required by operational services and creating a consistent long-term data archive for applications based on long time series. This mission will ensure the continuation and improvement of SAR operational services and applications addressing primarily medium- to high-resolution applications through a main mode of operation that features both a wide swath (250 km) and high geometric (5 × 20 m) and radiometric resolution, allowing imaging of global landmasses, coastal zones, sea ice, polar areas, and shipping routes at high resolution. The Sentinel-1 main operational mode (Interferometric Wide Swath) will allow to have a complete coverage of the Earth in 6 days in the operational configuration when the two Sentinel-1 spacecraft will be in orbit simultaneously. High priority areas like Europe, Canada and some shipping routes will be covered almost daily. This high global observation frequency is unprecedented and cannot be reached with any other current radar mission. Envisat, for example, which was the 'workhorse' in this domain up to April 2012, reached global coverage every 35 days. Sentinel-1 data products will be made available systematically and free of charge to all users including institutional users, the general public, scientific and commercial users. The transition of the Copernicus programme from the development to operational phase will take place at about the same time when the first Sentinel-1 satellite will be launched. During the operational phase, funding of the programme will come from the European Union Multiannual Financial Framework (MFF) for the years 2014-2020. The EU Copernicus Regulation, laying down the legal basis for the EU operational Copernicus programme, is currently in its final phase of approval by the European Parliament and Council. Based on this, the future EU-ESA Copernicus Agreement will define the modalities for the cooperation between ESA and the EU for the period 2014-2020 and will regulate the budget implementation tasks entrusted to ESA by the EU for the accomplishment of the space segment and the programme operations phase. The agreement, once signed, will pave the way for important procurements over the next seven years in the Earth observation domain.
DUACS: Toward High Resolution Sea Level Products
NASA Astrophysics Data System (ADS)
Faugere, Y.; Gerald, D.; Ubelmann, C.; Claire, D.; Pujol, M. I.; Antoine, D.; Desjonqueres, J. D.; Picot, N.
2016-12-01
The DUACS system produces, as part of the CNES/SALP project, and the Copernicus Marine Environment and Monitoring Service, high quality multimission altimetry Sea Level products for oceanographic applications, climate forecasting centers, geophysic and biology communities... These products consist in directly usable and easy to manipulate Level 3 (along-track cross-calibrated SLA) and Level 4 products (multiple sensors merged as maps or time series) and are available in global and regional version (Mediterranean Sea, Arctic, European Shelves …).The quality of the products is today limited by the altimeter technology "Low Resolution Mode" (LRM), and the lack of available observations. The launch of 2 new satellites in 2016, Jason-3 and Sentinel-3A, opens new perspectives. Using the global Synthetic Aperture Radar mode (SARM) coverage of S3A and optimizing the LRM altimeter processing (retracking, editing, ...) will allow us to fully exploit the fine-scale content of the altimetric missions. Thanks to this increase of real time altimetry observations we will also be able to improve Level-4 products by combining these new Level-3 products and new mapping methodology, such as dynamic interpolation. Finally these improvements will benefit to downstream products : geostrophic currents, Lagrangian products, eddy atlas… Overcoming all these challenges will provide major upgrades of Sea Level products to better fulfill user needs.
Mapping the zebrafish brain methylome using reduced representation bisulfite sequencing
Chatterjee, Aniruddha; Ozaki, Yuichi; Stockwell, Peter A; Horsfield, Julia A; Morison, Ian M; Nakagawa, Shinichi
2013-01-01
Reduced representation bisulfite sequencing (RRBS) has been used to profile DNA methylation patterns in mammalian genomes such as human, mouse and rat. The methylome of the zebrafish, an important animal model, has not yet been characterized at base-pair resolution using RRBS. Therefore, we evaluated the technique of RRBS in this model organism by generating four single-nucleotide resolution DNA methylomes of adult zebrafish brain. We performed several simulations to show the distribution of fragments and enrichment of CpGs in different in silico reduced representation genomes of zebrafish. Four RRBS brain libraries generated 98 million sequenced reads and had higher frequencies of multiple mapping than equivalent human RRBS libraries. The zebrafish methylome indicates there is higher global DNA methylation in the zebrafish genome compared with its equivalent human methylome. This observation was confirmed by RRBS of zebrafish liver. High coverage CpG dinucleotides are enriched in CpG island shores more than in the CpG island core. We found that 45% of the mapped CpGs reside in gene bodies, and 7% in gene promoters. This analysis provides a roadmap for generating reproducible base-pair level methylomes for zebrafish using RRBS and our results provide the first evidence that RRBS is a suitable technique for global methylation analysis in zebrafish. PMID:23975027
Advanced Mass Spectrometric Methods for the Rapid and Quantitative Characterization of Proteomes
Smith, Richard D.
2002-01-01
Progress is reviewedmore » towards the development of a global strategy that aims to extend the sensitivity, dynamic range, comprehensiveness and throughput of proteomic measurements based upon the use of high performance separations and mass spectrometry. The approach uses high accuracy mass measurements from Fourier transform ion cyclotron resonance mass spectrometry (FTICR) to validate peptide ‘accurate mass tags’ (AMTs) produced by global protein enzymatic digestions for a specific organism, tissue or cell type from ‘potential mass tags’ tentatively identified using conventional tandem mass spectrometry (MS/MS). This provides the basis for subsequent measurements without the need for MS/ MS. High resolution capillary liquid chromatography separations combined with high sensitivity, and high resolution accurate FTICR measurements are shown to be capable of characterizing peptide mixtures of more than 10 5 components. The strategy has been initially demonstrated using the microorganisms Saccharomyces cerevisiae and Deinococcus radiodurans. Advantages of the approach include the high confidence of protein identification, its broad proteome coverage, high sensitivity, and the capability for stableisotope labeling methods for precise relative protein abundance measurements. Abbreviations : LC, liquid chromatography; FTICR, Fourier transform ion cyclotron resonance; AMT, accurate mass tag; PMT, potential mass tag; MMA, mass measurement accuracy; MS, mass spectrometry; MS/MS, tandem mass spectrometry; ppm, parts per million.« less
New Multispectral Cloud Retrievals from MODIS
NASA Technical Reports Server (NTRS)
Platnick, Steven; Tsay, Si-Chee; Ackerman, Steven A.; Gray, Mark A.; Moody, Eric G.; Li, Jason Y.; Arnold, G. T.; King, Michael D. (Technical Monitor)
2000-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999. It achieved its final orbit and began Earth observations on February 24, 2000. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, sun-synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 micrometers with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean, and atmospheric processes. In this paper I will describe the various methods being used for the remote sensing of cloud properties using MODIS data, focusing primarily on the MODIS cloud mask used to distinguish clouds, clear sky, heavy aerosol, and shadows on the ground, and on the remote sensing of cloud optical properties, especially cloud optical thickness and effective radius of cloud drops and ice crystals. Results will be presented of MODIS cloud properties both over the land and over the ocean, showing the consistency in cloud retrievals over various ecosystems used in the retrievals. The implications of this new observing system on global analysis of the Earth's environment will be discussed.
Multispectral Cloud Retrievals from MODIS on Terra and Aqua
NASA Technical Reports Server (NTRS)
King, Michael D.; Platnick, Steven; Ackerman, Steven A.; Menzel, W. Paul; Gray, Mark A.; Moody, Eric G.
2002-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999 and the Aqua spacecraft on April 26, 2002. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from each polar-orbiting, sun-synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 microns with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). In this paper we will describe the various methods being used for the remote sensing of cloud properties using MODIS data, focusing primarily on the MODIS cloud mask used to distinguish clouds, clear sky, heavy aerosol, and shadows on the ground, and on the remote sensing of cloud optical properties, especially cloud optical thickness and effective radius of water drops and ice crystals. Additional properties of clouds derived from multispectral thermal infrared measurements, especially cloud top pressure and emissivity, will also be described. Results will be presented of MODIS cloud properties both over the land and over the ocean, showing the consistency in cloud retrievals over various ecosystems used in the retrievals. The implications of this new observing system on global analysis of the Earth's environment will be discussed.
New Multispectral Cloud Retrievals from MODIS
NASA Technical Reports Server (NTRS)
King, Michael D.; Platnick, Steven; Tsay, Si-Chee; Ackerman, Steven A.; Menzel, W. Paul; Gray, Mark A.; Moody, Eric G.; Li, Jason Y.; Arnold, G. Thomas
2001-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) was developed by NASA and launched onboard the Terra spacecraft on December 18, 1999. It achieved its final orbit and began Earth observations on February 24, 2000. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, sun- synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 microns with spatial resolutions of 250 m (two bands), 500 m (five bands) and 1000 m (29 bands). In this paper we will describe the various methods being used for the remote sensing of cloud properties using MODIS data, focusing primarily on the MODIS cloud mask used to distinguish clouds, clear sky, heavy aerosol, and shadows on the ground, and on the remote sensing of cloud optical properties, especially cloud optical thickness and effective radius of water drops and ice crystals. Additional properties of clouds derived from multispectral thermal infrared measurements, especially cloud top pressure and emissivity, will also be described. Results will be presented of MODIS cloud properties both over the land and over the ocean, showing the consistency in cloud retrievals over various ecosystems used in the retrievals. The implications of this new observing system on global analysis of the Earth's environment will be discussed.
Global Adjoint Tomography: Combining Big Data with HPC Simulations
NASA Astrophysics Data System (ADS)
Bozdag, E.; Lefebvre, M. P.; Lei, W.; Peter, D. B.; Smith, J. A.; Komatitsch, D.; Tromp, J.
2014-12-01
The steady increase in data quality and the number of global seismographic stations have substantially grown the amount of data available for construction of Earth models. Meanwhile, developments in the theory of wave propagation, numerical methods and HPC systems have enabled unprecedented simulations of seismic wave propagation in realistic 3D Earth models which lead the extraction of more information from data, ultimately culminating in the use of entire three-component seismograms.Our aim is to take adjoint tomography further to image the entire planet which is one of the extreme cases in seismology due to its intense computational requirements and vast amount of high-quality seismic data that can potentially be assimilated in inversions. We have started low resolution (T > 27 s, soon will be > 17 s) global inversions with 253 earthquakes for a transversely isotropic crust and mantle model on Oak Ridge National Laboratory's Cray XK7 "Titan" system. Recent improvements in our 3D solvers, such as the GPU version of the SPECFEM3D_GLOBE package, will allow us perform higher-resolution (T > 9 s) and longer-duration (~180 m) simulations to take the advantage of high-frequency body waves and major-arc surface waves to improve imbalanced ray coverage as a result of uneven distribution of sources and receivers on the globe. Our initial results after 10 iterations already indicate several prominent features reported in high-resolution continental studies, such as major slabs (Hellenic, Japan, Bismarck, Sandwich, etc.) and enhancement in plume structures (the Pacific superplume, the Hawaii hot spot, etc.). Our ultimate goal is to assimilate seismic data from more than 6,000 earthquakes within the magnitude range 5.5 ≤ Mw ≤ 7.0. To take full advantage of this data set on ORNL's computational resources, we need a solid framework for managing big data sets during pre-processing (e.g., data requests and quality checks), gradient calculations, and post-processing (e.g., pre-conditioning and smoothing gradients) where we address the bottlenecks in our global seismic workflow based on ORNL's ADIOS libraries. We will present our "first generation" model, discuss challenges and future directions in global seismology.
Establishment and analysis of High-Resolution Assimilation Dataset of water-energy cycle over China
NASA Astrophysics Data System (ADS)
Wen, Xiaohang; Liao, Xiaohan; Dong, Wenjie; Yuan, Wenping
2015-04-01
For better prediction and understanding of water-energy exchange process and land-atmospheric interaction, the in-situ observed meteorological data which were acquired from China Meteorological Administration (CMA) were assimilated in the Weather Research and Forecasting (WRF) model and the monthly Green Vegetation Coverage (GVF) data, which was calculated by the Normalized Difference Vegetation Index (NDVI) of Earth Observing System Moderate-Resolution Imaging Spectroradiometer (EOS-MODIS), Digital Elevation Model (DEM) data of the Shuttle Radar Topography Mission (SRTM) system were also integrated in the WRF model over China. Further, the High-Resolution Assimilation Dataset of water-energy cycle over China (HRADC) was produced by WRF model. This dataset include 25 km horizontal resolution near surface meteorological data such as air temperature, humidity, ground temperature, and pressure at 19 levels, soil temperature and soil moisture at 4 levels, green vegetation coverage, latent heat flux, sensible heat flux, and ground heat flux for 3 hours. In this study, we 1) briefly introduce the cycling 3D-Var assimilation method; 2) Compare results of meteorological elements such as 2 m temperature, precipitation and ground temperature generated by the HRADC with the gridded observation data from CMA, and Global Land Data Assimilation System (GLDAS) output data from National Aeronautics and Space Administration (NASA). It is found that the results of 2 m temperature were improved compared with the control simulation and has effectively reproduced the observed patterns, and the simulated results of ground temperature, 0-10 cm soil temperature and specific humidity were as much closer to GLDAS outputs. Root mean square errors are reduced in assimilation run than control run, and the assimilation run of ground temperature, 0-10 cm soil temperature, radiation and surface fluxes were agreed well with the GLDAS outputs over China. The HRADC could be used in further research on the long period climatic effects and characteristics of water-energy cycle over China.
NASA Astrophysics Data System (ADS)
Weiss, J. R.; Walters, R. J.; Wright, T. J.; Hussain, E.; González, P. J.; Hooper, A. J.
2017-12-01
Accurate and high-resolution measurements of interseismic crustal velocity and the strain-rate fields derived from these measurements are an important input for the assessment of earthquake hazard. However, most strain-rate estimation methods and associated seismicity forecasts rely heavily on Global Navigation Satellite System (GNSS) networks with sparse and heterogeneous spatial coverage, limiting both accuracy and resolution. Interferometric Synthetic Aperture Radar (InSAR) provides remotely-sensed observations of surface motion, with accuracy comparable to GNSS data, and with a spatial resolution of a few tens of meters. The recently launched Sentinel-1 (S1) radar satellites can measure deformation at the tectonic-plate scale and across slowly straining regions where earthquake hazard is poorly characterised. We are producing large-scale crustal velocity and strain-rate fields for the Alpine-Himalayan belt (AHB) by augmenting global GNSS data compilations with InSAR-derived surface velocities. We are also systematically processing S1 interferograms for the AHB and these products are freely available to the geoscience community. We focus on the Anatolian microplate, where we have used both Envisat and S1 data to measure crustal velocity. We address some of the challenges associated with merging the complementary geodetic datasets including reference-frame issues, treatment of uncertainties, and comparison of different velocity/strain-rate inversion methods. We use synthetic displacement fields to illustrate how inclusion of InSAR can aid in identifying features such as unmapped active faults and fault segments that are creeping. From our preliminary results for Anatolia, we investigate the spatial distribution of strain and variation of strain rates during the seismic cycle.
NASA Astrophysics Data System (ADS)
Prigent, Catherine; Aires, Filipe; Heygster, Georg
2017-04-01
Ocean surface characterization from satellites is required to understand, monitor and predict the general circulation of the ocean and atmosphere. With more than 70% global cloud coverage at any time, visible and infrared satellite observations only provide limited information. The polar regions are particularly vulnerable to the climate changes and are home to complex mesoscale mechanisms that are still poorly understood. They are also under very persis- tent cloudiness. Passive microwave observations can provide surface information such as Sea Surface Temperature (SST) and Sea Ice Concentration (SIC) regardless of the cloud cover, but up to now they were limited in spatial resolution. Here, we propose a passive microwave conically scanning imager, MICROWAT, in a polar orbit, for the retrieval of the SST and SIC, with a spatial resolution of 15km. It observes at 6 and 10GHz, with low-noise dual polarization receivers, and a foldable mesh antenna of 5m-diameter. Furthermore, MICROWAT will fly in tandem with MetOp-SG B to benefit from the synergy with scatterometers (SCA) and microwave imagers (MWI). MICROWAT will provide global SST estimates, twice daily, regardless of cloud cover, with an accuracy of 0.3K and a spatial resolution of 15km. The SIC will be derived with an accuracy of 3%. With its unprecedented "all weather" accurate SST and SIC at 15km, MICROWAT will provide the atmospheric and oceanic forecasting sys- tems with products compatible with their increasing spatial resolution and complexity, with impact for societal applications. It will also answer fundamental science questions related to the ocean, the atmosphere and their interactions. * Prigent, Aires, Bernardo, Orlhac, Goutoule, Roquet, & Donlon, Analysis of the potential and limitations of microwave radiometry for the retrieval of sea surface temperature: Definition
NASA Astrophysics Data System (ADS)
Levelt, P.; Joiner, J.; Tamminen, J.; Veefkind, P.; Bhartia, P. K.; Court, A. J.; Vlemmix, T.
2017-12-01
Keywords: emission monitoring, air quality, climate, atmospheric composition The Ozone Monitoring Instrument (OMI), launched on board of NASA's EOS-Aura spacecraft on July 15, 2004, provides unique contributions to the monitoring of the ozone layer, air quality and climate from space. With a data record of 13 years, OMI provides the longest NO2 and SO2 record from space, which is essential to understand the changes to emissions globally. The combination of urban scale resolution (13 x 24 km2 in nadir) and daily global coverage proved to be key features for the air quality community. Due to the operational Very Fast Delivery (VFD / direct readout) and Near Real Time (NRT) availability of the data, OMI also plays an important role in the early developments of operational services in the atmospheric chemistry domain. For example, OMI data is currently used operationally for improving air quality forecasts, for inverting high-resolution emission maps, the UV forecast and for volcanic plume warning systems for aviation. An overview of air quality applications, emission inventory inversions and trend analyses based on the OMI data record will be presented. An outlook will be given on the potentials of augmenting this record with the high resolution air quality measurements of TROPOMI (3,5 x 7 km2) and new satellite instrumentation entering the imaging domain, such as the TROPOLITE instrument ( 1 x 1 km2). Potential of imaging type of NO2 measurements in the the climate and air quality domain will be given, most notably on the use of high resolution NO2 measurements for pin-pointing anthropogenic CO2 emissions.
CCTV Coverage Index Based on Surveillance Resolution and Its Evaluation Using 3D Spatial Analysis
Choi, Kyoungah; Lee, Impyeong
2015-01-01
We propose a novel approach to evaluating how effectively a closed circuit television (CCTV) system can monitor a targeted area. With 3D models of the target area and the camera parameters of the CCTV system, the approach produces surveillance coverage index, which is newly defined in this study as a quantitative measure for surveillance performance. This index indicates the proportion of the space being monitored with a sufficient resolution to the entire space of the target area. It is determined by computing surveillance resolution at every position and orientation, which indicates how closely a specific object can be monitored with a CCTV system. We present full mathematical derivation for the resolution, which depends on the location and orientation of the object as well as the geometric model of a camera. With the proposed approach, we quantitatively evaluated the surveillance coverage of a CCTV system in an underground parking area. Our evaluation process provided various quantitative-analysis results, compelling us to examine the design of the CCTV system prior to its installation and understand the surveillance capability of an existing CCTV system. PMID:26389909
Globalization and multi-spatial trends in the coverage of protected-area conservation (1980-2000).
Zimmerer, Karl S; Galt, Ryan E; Buck, Margaret V
2004-12-01
This study is focused on the global expansion of protected-area coverage that occurred during the 1980--2000 period. We examine the multi-scale patterning of four of the basic facets of this expansion: i) estimated increases at the world-regional and country-level scales of total protected-area coverage; ii) transboundary protected areas; iii) conservation corridor projects; and iv) type of conservation management. Geospatial patterning of protected-area designations is a reflection of the priorities of global conservation organizations and the globalization of post-Cold War political and economic arrangements. Local and national-level factors (political leadership and infrastructure) as well as international relations such as multilateral and bilateral aid combine with these globalization processes to impact the extent, type, and location of protected-area designations. We conclude that the interaction of these factors led to the creation and reinforcement of marked spatial differences (rather than tendencies toward worldwide evenness or homogenization) in the course of protected-area expansion during the 1980--2000 period.
Historical record of Landsat global coverage
Goward, Samuel; Arvidson, Terry; Williams, Darrel; Faundeen, John; Irons, James; Franks, Shannon
2006-01-01
The long-term, 34+ year record of global Landsat remote sensing data is a critical resource to study the Earth system and human impacts on this system. The National Satellite Land Remote Sensing Data Archive (NSLRSDA) is charged by public law to: “maintain a permanent, comprehensive Government archive of global Landsat and other land remote sensing data for long-term monitoring and study of the changing global environment” (U.S. Congress, 1992). The advisory committee for NSLRSDA requested a detailed analysis of observation coverage within the U.S. Landsat holdings, as well as that acquired and held by International Cooperator (IC) stations. Our analyses, to date, have found gaps of varying magnitude in U.S. holdings of Landsat global coverage data, which appear to reflect technical or administrative variations in mission operations. In many cases it may be possible to partially fill these gaps in U.S. holdings through observations that were acquired and are now being held at International Cooperator stations.
ERIC Educational Resources Information Center
Boateng, C. A.
2015-01-01
Global problems such as climate change, which have deeper implications for survival of mankind on this planet, needs to be given wider attention in the quest for knowledge. It is expected that, improved knowledge derived from curriculum coverage may promote greater public awareness of such important global issue. This research aims at examining…
Global Moon Coverage via Hyperbolic Flybys
NASA Technical Reports Server (NTRS)
Buffington, Brent; Strange, Nathan; Campagnola, Stefano
2012-01-01
The scientific desire for global coverage of moons such as Jupiter's Galilean moons or Saturn's Titan has invariably led to the design of orbiter missions. These orbiter missions require a large amount of propellant needed to insert into orbit around such small bodies, and for a given launch vehicle, the additional propellant mass takes away from mass that could otherwise be used for scientific instrumentation on a multiple flyby-only mission. This paper will present methods--expanding upon techniques developed for the design of the Cassini prime and extended missions--to obtain near global moon coverage through multiple flybys. Furthermore we will show with proper instrument suite selection, a flyby-only mission can provide science return similar (and in some cases greater) to that of an orbiter mission.
NASA Astrophysics Data System (ADS)
Lazreg, Nissen; Ben Bahri, Omar; Besbes, Kamel
2018-02-01
Costal monitoring is focused on fast response to illegal immigration and illegal ship traffic. Especially, the illegal ship traffic has been present in media since April 2015, as the number of reported deaths of immigrants crossing the Mediterranean significantly increased. Satellite images provide a possibility to at least partially control both types of events. This paper defines the principal criteria to select the best satellite constellation architecture for maritime and coastal monitoring, filling the gaps of imagery techniques in term of real-time control. The primary purpose of a constellation is to obtain global measurement improving the temporal resolution. The small size and low-cost are the main factors, which make CubeSats ideal for use in constellations. We propose a constellation of 9 Cubesats distributed evenly in 3 different planes. This reduces the revisit time enhancing the coverage duration. In addition, it also allows observing fire, damage on building and similar disasters. In this analysis, the performance criteria were reported such as the revisit time, the vision duration and the area coverage.
A SmallSat constellation mission architecture for a GRACE-type mission design
NASA Astrophysics Data System (ADS)
Deccia, C. M. A.; Nerem, R. S.; Yunck, T.
2017-12-01
The Gravity Recovery and Climate Experiment (GRACE) launched in 2002 and has been providing invaluable information of Earth's time-varying gravity field and GRACE-FO will continue this time series. For this work, we focus on architectures of future post-GRACE-FO like missions. Single pairs of satellites like GRACE and GRACE-FO are inherently limited in their spatio-temporal coverage. Full global coverage for a single pair can take up to 30 days for spatial resolutions of a few hundred kilometers, thus a single satellite pair is unable to observe sub-monthly signals in the Earth's time varying gravity field (e.g. hydrologic signals, etc.). Small satellite systems are becoming increasingly affordable and will soon allow a constellation of GRACE-type satellites to be deployed, with the capability to range between multiple satellites. Here, using simulation studies, we investigate the performance of such a constellation for different numbers of satellites (N) and different orbital configurations, in order to understand the improved performance that might be gained from such future mission architectures.
Optimal A-Train Data Utilization: A Use Case of Aura OMI L2G and MERRA-2 Aerosol Products
NASA Technical Reports Server (NTRS)
Zeng, Jian; Shen, Suhung; Wei, Jennifer; Meyer, David J.
2017-01-01
Ozone Monitoring Instrument (OMI) aboard NASA's Aura mission measures ozone column and profile, aerosols, clouds, surface UV irradiance, and the trace gases including NO2, SO2, HCHO, BrO, and OClO using UltraViolet electromagnetic spectrum (280 - 400 nm) with a daily global coverage and a pixel spatial resolution of 13 km × 24 km at nadir, and it's been one of the key instruments to study the Earth's atmospheric composition and chemistry. The second Modern-Era Retrospective analysis for Research and Applications (MERRA-2) is NASA's atmospheric reanalysis using an upgraded version of Goddard Earth Observing System Model, version 5 (GEOS-5) data assimilation system. Compared to its predecessor MERRA, MERRA-2 is enhanced with more aspects of the Earth system among which is aerosol assimilation. When comparing between satellite pixel measurements and modeled grid data, how to properly handle counterpart pairing is critical considering their spatial and temporal variations. The comparison between satellite and model data by simply using Level 3 (L3) products may result biases due to lack of detailed temporal information. It has been preferred to inter-compare or implement satellite derived physical quantity (i.e., Level 2 (L2) Swath type) directly with/to model measurements with higher temporal and spatial resolution as possible. However, this has posed a challenge in the community to handle. Rather than directly handling the L2 or L3 data, there is a Level 2G (L2G) product conserving L2 pixel scientific data quality but in Grid type with the global coverage. In this presentation, we would like to demonstrate the optimal utilization of OMI L2G daily aerosol products by comparing with MERRA-2 hourly aerosol simulations matched well in both space and time.
NASA Astrophysics Data System (ADS)
Ombadi, Mohammed; Nguyen, Phu; Sorooshian, Soroosh
2017-12-01
Intensity Duration Frequency (IDF) curves are essential for the resilient design of infrastructures. Since their earlier development, IDF relationships have been derived using precipitation records from rainfall gauge stations. However, with the recent advancement in satellite observation of precipitation which provides near global coverage and high spatiotemporal resolution, it is worthy of attention to investigate the validity of utilizing the relatively short record length of satellite rainfall to generate robust IDF relationships. These satellite-based IDF can address the paucity of such information in the developing countries. Few studies have used satellite precipitation data in IDF development but mainly focused on merging satellite and gauge precipitation. In this study, however, IDF have been derived solely from satellite observations using PERSIANN-CDR (Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks-Climate Data Record). The unique PERSIANN-CDR attributes of high spatial resolution (0.25°×0.25°), daily temporal resolution and a record dating back to 1983 allow for the investigation at fine resolution. The results are compared over most of the contiguous United States against NOAA Atlas 14. The impact of using different methods of sampling, distribution estimators and regionalization in the resulting relationships is investigated. Main challenges to estimate robust and accurate IDF from satellite observations are also highlighted.
An Overview of Production and Validation of the SMAP Passive Soil Moisture Product
NASA Technical Reports Server (NTRS)
Chan, S.; O'Neill, P.; Njoku, E.; Jackson, T.; Bindlish, R.
2015-01-01
The Soil Moisture Active Passive (SMAP) mission is an L-band mission scheduled for launch in Jan. 2015. The SMAP instruments consist of a radar and a radiometer to obtain complementary information from space for soil moisture and freeze/thaw state research and applications. By utilizing novel designs in antenna construction, retrieval algorithms, and acquisition hardware, SMAP provides a capability for global mapping of soil moisture and freeze/thaw state with unprecedented accuracy, resolution, and coverage. This improvement in hydrosphere state measurement is expected to advance our understanding of the processes that link the terrestrial water, energy and carbon cycles, improve our capability in flood prediction and drought monitoring, and enhance our skills in weather and climate forecast. For swath-based soil moisture measurement, SMAP generates three operational geophysical data products: (1) the radiometer-only soil moisture product (L2_SM_P) posted at 36-kilometer resolution, (2) the radar-only soil moisture product (L2_SM_A) posted at 3-kilometers resolution, and (3) the radar-radiometer combined soil moisture product (L2_SM_AP) posted at 9-kilometers resolution. Each product draws on the strengths of the underlying sensor(s) and plays a unique role in hydroclimatological and hydrometeorological applications. A full suite of SMAP data products is given in Table 1.
NASA Astrophysics Data System (ADS)
Larson, Timothy P.; Schou, Jesper
2018-02-01
Building upon our previous work, in which we analyzed smoothed and subsampled velocity data from the Michelson Doppler Imager (MDI), we extend our analysis to unsmoothed, full-resolution MDI data. We also present results from the Helioseismic and Magnetic Imager (HMI), in both full resolution and processed to be a proxy for the low-resolution MDI data. We find that the systematic errors that we saw previously, namely peaks in both the high-latitude rotation rate and the normalized residuals of odd a-coefficients, are almost entirely absent in the two full-resolution analyses. Furthermore, we find that both systematic errors seem to depend almost entirely on how the input images are apodized, rather than on resolution or smoothing. Using the full-resolution HMI data, we confirm our previous findings regarding the effect of using asymmetric profiles on mode parameters, and also find that they occasionally result in more stable fits. We also confirm our previous findings regarding discrepancies between 360-day and 72-day analyses. We further investigate a six-month period previously seen in f-mode frequency shifts using the low-resolution datasets, this time accounting for solar-cycle dependence using magnetic-field data. Both HMI and MDI saw prominent six-month signals in the frequency shifts, but we were surprised to discover that the strongest signal at that frequency occurred in the mode coverage for the low-resolution proxy. Finally, a comparison of mode parameters from HMI and MDI shows that the frequencies and a-coefficients agree closely, encouraging the concatenation of the two datasets.
Data Processing for the Space-Based Desis Hyperspectral Sensor
NASA Astrophysics Data System (ADS)
Carmona, E.; Avbelj, J.; Alonso, K.; Bachmann, M.; Cerra, D.; Eckardt, A.; Gerasch, B.; Graham, L.; Günther, B.; Heiden, U.; Kerr, G.; Knodt, U.; Krutz, D.; Krawcyk, H.; Makarau, A.; Miller, R.; Müller, R.; Perkins, R.; Walter, I.
2017-05-01
The German Aerospace Center (DLR) and Teledyne Brown Engineering (TBE) have established a collaboration to develop and operate a new space-based hyperspectral sensor, the DLR Earth Sensing Imaging Spectrometer (DESIS). DESIS will provide spacebased hyperspectral data in the VNIR with high spectral resolution and near-global coverage. While TBE provides the platform and infrastructure for operation of the DESIS instrument on the International Space Station, DLR is responsible for providing the instrument and the processing software. The DESIS instrument is equipped with novel characteristics for an imaging spectrometer such high spectral resolution (2.55 nm), a mirror pointing unit or a CMOS sensor operated in rolling shutter mode. We present here an overview of the DESIS instrument and its processing chain, emphasizing the effect of the novel characteristics of DESIS in the data processing and final data products. Furthermore, we analyse in more detail the effect of the rolling shutter on the DESIS data and possible mitigation/correction strategies.
NASA Technical Reports Server (NTRS)
Foldes, P.
1986-01-01
The instrumentation problems associated with the measurement of soil moisture with a meaningful spatial and temperature resolution at a global scale are addressed. For this goal only medium term available affordable technology will be considered. The study while limited in scope, will utilize a large scale antenna structure, which is being developed presently as an experimental model. The interface constraints presented by a singel Space Transportation System (STS) flight will be assumed. Methodology consists of the following steps: review of science requirements; analyze effects of these requirements; present basic system engineering considerations and trade-offs related to orbit parameters, number of spacecraft and their lifetime, observation angles, beamwidth, crossover and swath, coverage percentage, beam quality and resolution, instrument quantities, and integration time; bracket the key system characteristics and develop an electromagnetic design of the antenna-passive radiometer system. Several aperture division combinations and feed array concepts are investigated to achieve maximum feasible performacne within the stated STS constraints.
NASA Astrophysics Data System (ADS)
De Smedt, Isabelle; Theys, Nicolas; Yu, Huan; Danckaert, Thomas; Lerot, Christophe; Compernolle, Steven; Van Roozendael, Michel; Richter, Andreas; Hilboll, Andreas; Peters, Enno; Pedergnana, Mattia; Loyola, Diego; Beirle, Steffen; Wagner, Thomas; Eskes, Henk; van Geffen, Jos; Folkert Boersma, Klaas; Veefkind, Pepijn
2018-04-01
On board the Copernicus Sentinel-5 Precursor (S5P) platform, the TROPOspheric Monitoring Instrument (TROPOMI) is a double-channel, nadir-viewing grating spectrometer measuring solar back-scattered earthshine radiances in the ultraviolet, visible, near-infrared, and shortwave infrared with global daily coverage. In the ultraviolet range, its spectral resolution and radiometric performance are equivalent to those of its predecessor OMI, but its horizontal resolution at true nadir is improved by an order of magnitude. This paper introduces the formaldehyde (HCHO) tropospheric vertical column retrieval algorithm implemented in the S5P operational processor and comprehensively describes its various retrieval steps. Furthermore, algorithmic improvements developed in the framework of the EU FP7-project QA4ECV are described for future updates of the processor. Detailed error estimates are discussed in the light of Copernicus user requirements and needs for validation are highlighted. Finally, verification results based on the application of the algorithm to OMI measurements are presented, demonstrating the performances expected for TROPOMI.
Global stability of a two-mediums rumor spreading model with media coverage
NASA Astrophysics Data System (ADS)
Huo, Liang'an; Wang, Li; Song, Guoxiang
2017-09-01
Rumor spreading is a typical form of social communication and plays a significant role in social life, and media coverage has a great influence on the spread of rumor. In this paper, we present a new model with two media coverage to investigate the impact of the different mediums on rumor spreading. Then, we calculate the equilibria of the model and construct the reproduction number ℜ0. And we prove the global asymptotic stability of equilibria by using Lyapunov functions. Finally, we can conclude that the transition rate of the ignorants between two mediums has a direct effect on the scale of spreaders, and different media coverage has significant effects on the dynamics behaviors of rumor spreading.
Lunar Topography: Results from the Lunar Orbiter Laser Altimeter
NASA Technical Reports Server (NTRS)
Neumann, Gregory; Smith, David E.; Zuber, Maria T.; Mazarico, Erwan
2012-01-01
The Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter (LRO) has been operating nearly continuously since July 2009, accumulating over 6 billion measurements from more than 2 billion in-orbit laser shots. LRO's near-polar orbit results in very high data density in the immediate vicinity of the lunar poles, with full coverage at the equator from more than 12000 orbital tracks averaging less than 1 km in spacing at the equator. LRO has obtained a global geodetic model of the lunar topography with 50-meter horizontal and 1-m radial accuracy in a lunar center-of-mass coordinate system, with profiles of topography at 20-m horizontal resolution, and 0.1-m vertical precision. LOLA also provides measurements of reflectivity and surface roughness down to its 5-m laser spot size. With these data LOLA has measured the shape of all lunar craters 20 km and larger. In the proposed extended mission commencing late in 2012, LOLA will concentrate observations in the Southern Hemisphere, improving the density of the polar coverage to nearly 10-m pixel resolution and accuracy to better than 20 m total position error. Uses for these data include mission planning and targeting, illumination studies, geodetic control of images, as well as lunar geology and geophysics. Further improvements in geodetic accuracy are anticipated from the use of re ned gravity fields after the successful completion of the Gravity Recovery and Interior Laboratory (GRAIL) mission in 2012.
Dzyubachyk, Oleh; Khmelinskii, Artem; Plenge, Esben; Kok, Peter; Snoeks, Thomas J A; Poot, Dirk H J; Löwik, Clemens W G M; Botha, Charl P; Niessen, Wiro J; van der Weerd, Louise; Meijering, Erik; Lelieveldt, Boudewijn P F
2014-01-01
In small animal imaging studies, when the locations of the micro-structures of interest are unknown a priori, there is a simultaneous need for full-body coverage and high resolution. In MRI, additional requirements to image contrast and acquisition time will often make it impossible to acquire such images directly. Recently, a resolution enhancing post-processing technique called super-resolution reconstruction (SRR) has been demonstrated to improve visualization and localization of micro-structures in small animal MRI by combining multiple low-resolution acquisitions. However, when the field-of-view is large relative to the desired voxel size, solving the SRR problem becomes very expensive, in terms of both memory requirements and computation time. In this paper we introduce a novel local approach to SRR that aims to overcome the computational problems and allow researchers to efficiently explore both global and local characteristics in whole-body small animal MRI. The method integrates state-of-the-art image processing techniques from the areas of articulated atlas-based segmentation, planar reformation, and SRR. A proof-of-concept is provided with two case studies involving CT, BLI, and MRI data of bone and kidney tumors in a mouse model. We show that local SRR-MRI is a computationally efficient complementary imaging modality for the precise characterization of tumor metastases, and that the method provides a feasible high-resolution alternative to conventional MRI.
NASA Technical Reports Server (NTRS)
Van Donkelaar, A.; Martin, R. V.; Brauer, M.; Kahn, R.; Levy, R.; Verduzco, C.; Villeneuve, P.
2010-01-01
Exposure to airborne particles can cause acute or chronic respiratory disease and can exacerbate heart disease, some cancers, and other conditions in susceptible populations. Ground stations that monitor fine particulate matter in the air (smaller than 2.5 microns, called PM2.5) are positioned primarily to observe severe pollution events in areas of high population density; coverage is very limited, even in developed countries, and is not well designed to capture long-term, lower-level exposure that is increasingly linked to chronic health effects. In many parts of the developing world, air quality observation is absent entirely. Instruments aboard NASA Earth Observing System satellites, such as the MODerate resolution Imaging Spectroradiometer (MODIS) and the Multi-angle Imaging SpectroRadiometer (MISR), monitor aerosols from space, providing once daily and about once-weekly coverage, respectively. However, these data are only rarely used for health applications, in part because the can retrieve the amount of aerosols only summed over the entire atmospheric column, rather than focusing just on the near-surface component, in the airspace humans actually breathe. In addition, air quality monitoring often includes detailed analysis of particle chemical composition, impossible from space. In this paper, near-surface aerosol concentrations are derived globally from the total-column aerosol amounts retrieved by MODIS and MISR. Here a computer aerosol simulation is used to determine how much of the satellite-retrieved total column aerosol amount is near the surface. The five-year average (2001-2006) global near-surface aerosol concentration shows that World Health Organization Air Quality standards are exceeded over parts of central and eastern Asia for nearly half the year.
Evaluation and Validation of Updated MODIS C6 and VIIRS LAI/FPAR
NASA Astrophysics Data System (ADS)
Yan, K.; Park, T.; Chen, C.; Yang, B.; Yan, G.; Knyazikhin, Y.; Myneni, R. B.; CHOI, S.
2015-12-01
Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation (0.4-0.7 μm) absorbed by vegetation (FPAR) play a key role in characterizing vegetation canopy functioning and energy absorption capacity. With radiative transfer realization, MODIS onboard NASA EOS Terra and Aqua satellites has provided globally continuous LAI/FPAR since 2000 and continuously updated the products with better quality. And NPP VIIRS shows the measurement capability to extend high-quality LAI/FPAR time series data records as a successor of MODIS. The primary objectives of this study are 1) to evaluate and validate newly updated MODIS Collection 6 (C6) LAI/FPAR product which has finer resolution (500m) and improved biome type input, and 2) to examine and adjust VIIRS LAI/FPAR algorithm for continuity with MODIS'. For MODIS C6 investigation, we basically measure the spatial coverage (i.e., main radiative transfer algorithm execution), continuity and consistency with Collection 5 (C5), and accuracy with field measured LAI/FPAR. And we also validate C6 LAI/FPAR via comparing other possible global LAI/FPAR products (e.g., GLASS and CYCLOPES) and capturing co-varying seasonal signatures with climatic variables (e.g., temperature and precipitation). For VIIRS evaluation and adjustment, we first quantify possible difference between C5 and MODIS heritage based VIIRS LAI/FPAR. Then based on the radiative transfer theory of canopy spectral invariants, we find VIIRS- and biome-specific configurable parameters (single scattering albedo and uncertainty). These two practices for MODIS C6 and VIIRS LAI/FPAR products clearly suggest that (a) MODIS C6 has better coverage and accuracy than C5, (b) C6 shows consistent spatiotemporal pattern with C5, (c) VIIRS has the potential for producing MODIS-like global LAI/FPAR Earth System Data Records.
Design of Multishell Sampling Schemes with Uniform Coverage in Diffusion MRI
Caruyer, Emmanuel; Lenglet, Christophe; Sapiro, Guillermo; Deriche, Rachid
2017-01-01
Purpose In diffusion MRI, a technique known as diffusion spectrum imaging reconstructs the propagator with a discrete Fourier transform, from a Cartesian sampling of the diffusion signal. Alternatively, it is possible to directly reconstruct the orientation distribution function in q-ball imaging, providing so-called high angular resolution diffusion imaging. In between these two techniques, acquisitions on several spheres in q-space offer an interesting trade-off between the angular resolution and the radial information gathered in diffusion MRI. A careful design is central in the success of multishell acquisition and reconstruction techniques. Methods The design of acquisition in multishell is still an open and active field of research, however. In this work, we provide a general method to design multishell acquisition with uniform angular coverage. This method is based on a generalization of electrostatic repulsion to multishell. Results We evaluate the impact of our method using simulations, on the angular resolution in one and two bundles of fiber configurations. Compared to more commonly used radial sampling, we show that our method improves the angular resolution, as well as fiber crossing discrimination. Discussion We propose a novel method to design sampling schemes with optimal angular coverage and show the positive impact on angular resolution in diffusion MRI. PMID:23625329
NASA Astrophysics Data System (ADS)
Nastan, A.; Garay, M. J.; Witek, M. L.; Seidel, F.; Bull, M. A.; Kahn, R. A.; Diner, D. J.
2017-12-01
The NASA Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite has provided an 18-year-and-growing aerosol data record. MISR's V22 aerosol product has been used extensively in studies of regional and global climate and the health effects of particulate air pollution. The MISR team recently released a new version of this product (V23), which increases the spatial resolution from 17.6 km to 4.4 km, improves performance versus AERONET, and provides better spatial coverage, more accurate cloud screening, and improved radiometric conditioning relative to V22. The product formatting was also completely revamped to improve clarity and usability. Established and prospective users of the MISR aerosol product are invited to learn about the features and performance of the new product and to participate in one-on-one demonstrations of how to obtain, visualize, and analyze the new product. Because the aerosol product is used in generating atmospherically-corrected surface bidirectional reflectance factors, improvements in MISR's 1.1 km resolution land surface product are a by-product of the updated aerosol retrievals. Illustrative comparisons of the V22 and V23 aerosol and surface products will be shown.
The Gulf Stream in Ocean Reanalyses: 1993-2010
NASA Astrophysics Data System (ADS)
Chi, L.; Wolfe, C.; Hameed, S.
2017-12-01
In recent years, significant progress has been made in the development of high-resolution ocean reanalysis products. However, errors are likely to remain because of inadequate coverage of observations, model resolutions, physical parameterizations, etc. We compare the representation of the Gulf Stream (GS) in several widely used global reanalysis products with resolutions ranging from 1° to 1/12°. This intercomparison focuses on the Florida Current transport, the separation of GS near Cape Hatteras, GS properties along the Oleander Line (from New Jersey to Bermuda), GS path and the GS north wall positions between 73°W and 55°W. A large spread exists across the reanalysis products. HYCOM and GLORYS2v4 stand out for their top performance in most metrics. Some common biases are found in all discussed products; for example, the velocity structure of the GS near the Oleander Line is too symmetric and the maximum velocity is weaker than in observations. In addition, the annual mean values of GS separation latitude near Cape Hatteras, the GS transport, and net transport across Oleander Line (which runs from New Jersey to Bermuda), less than half of the reanalysis products are correlated to the observations at 95% confidence level.
Satellite Imagery Analysis for Automated Global Food Security Forecasting
NASA Astrophysics Data System (ADS)
Moody, D.; Brumby, S. P.; Chartrand, R.; Keisler, R.; Mathis, M.; Beneke, C. M.; Nicholaeff, D.; Skillman, S.; Warren, M. S.; Poehnelt, J.
2017-12-01
The recent computing performance revolution has driven improvements in sensor, communication, and storage technology. Multi-decadal remote sensing datasets at the petabyte scale are now available in commercial clouds, with new satellite constellations generating petabytes/year of daily high-resolution global coverage imagery. Cloud computing and storage, combined with recent advances in machine learning, are enabling understanding of the world at a scale and at a level of detail never before feasible. We present results from an ongoing effort to develop satellite imagery analysis tools that aggregate temporal, spatial, and spectral information and that can scale with the high-rate and dimensionality of imagery being collected. We focus on the problem of monitoring food crop productivity across the Middle East and North Africa, and show how an analysis-ready, multi-sensor data platform enables quick prototyping of satellite imagery analysis algorithms, from land use/land cover classification and natural resource mapping, to yearly and monthly vegetative health change trends at the structural field level.
NASA Technical Reports Server (NTRS)
Kahn, W. D.; Klosko, S. M.; Wells, W. T.
1982-01-01
Advances in satellite tracking data accuracy and coverage over the past 15 years have led to major improvements in global geopotential models. But the spacial resolution of the gravity field obtained solely from satellite dynamics sensed by tracking data is still of the order of 1000 km. Attention is given to an approach which will provide information regarding the fine structure of the gravity field on the basis of an application of local corrections to the global field. According to this approach, a basic satellite to satellite tracked (SST) range-rate measurement is constructed from the link between a ground station, a geosynchronous satellite (ATS 6), and a near-earth satellite (Apollo or GEOS 3). Attention is given to a mathematical model, the simulation of SST gravity anomaly estimation accuracies, a gravity anomaly estimation from GEOS 3/ATS 6 and Apollo/ATS 6 SST observations, and an evaluation of the mean gravity anomalies determined from SST.
Can we detect oceanic biodiversity hotspots from space?
De Monte, Silvia; Soccodato, Alice; Alvain, Séverine; d'Ovidio, Francesco
2013-10-01
Understanding the variability of marine biodiversity is a central issue in microbiology. Current observational programs are based on in situ studies, but their implementation at the global scale is particularly challenging, owing to the ocean extent, its temporal variability and the heterogeneity of the data sources on which compilations are built. Here, we explore the possibility of identifying phytoplanktonic biodiversity hotspots from satellite. We define a Shannon entropy index based on patchiness in ocean color bio-optical anomalies. This index provides a high resolution (1 degree) global coverage. It shows a relation to temperature and mid-latitude maxima in accordance with those previously evidenced in microbiological biodiversity model and observational studies. Regional maxima are in remarkable agreement with several known biodiversity hotspots for plankton organisms and even for higher levels of the marine trophic chain, as well as with some in situ planktonic biodiversity estimates (from Atlantic Meridional Transect cruise). These results encourage to explore marine biodiversity with a coordinated effort of the molecular, ecological and remote sensing communities.
NASA Astrophysics Data System (ADS)
Smith, T.; McLaughlin, D.
2017-12-01
Growing more crops to provide a secure food supply to an increasing global population will further stress land and water resources that have already been significantly altered by agriculture. The connection between production and resource use depends on crop yields and unit evapotranspiration (UET) rates that vary greatly, over both time and space. For regional and global analyses of food security it is appropriate to treat yield and UET as uncertain variables conditioned on climatic and soil properties. This study describes how probability distributions of these variables can be estimated by combining remotely sensed land use and evapotranspiration data with in situ agronomic and soils data, all available at different resolutions and coverages. The results reveal the influence of water and temperature stress on crop yield at large spatial scales. They also provide a basis for stochastic modeling and optimization procedures that explicitly account for uncertainty in the environmental factors that affect food production.
Evaluation of Current Planetary Boundary Layer Retrieval Capabilities from Space
NASA Technical Reports Server (NTRS)
Santanello, Joseph A., Jr.; Schaefer, Alexander J.; Blaisdell, John; Yorks, John
2016-01-01
The PBL over land remains a significant gap in our water and energy cycle understanding from space. This work combines unique NASA satellite and model products to demonstrate the ability of current sensors (advanced IR sounding and lidar) to retrieve PBL properties and in turn their potential to be used globally to evaluate and improve weather and climate prediction models. While incremental progress has been made in recent AIRS retrieval versions, insufficient vertical resolution remains in terms of detecting PBL properties. Lidar shows promise in terms of detecting vertical gradients (and PBLh) in the lower troposphere, but daytime conditions over land remain a challenge due to noise, and their coverage is limited to approximately 2 weeks or longer return times.
2012-12-19
VANDENBERG AFB, Calif.-- The truck transporting NASA's Landsat Data Continuity Mission, or LDCM, satellite backs into the processing facility at Vandenberg Air Force Base, Calif. for prelaunch checkout. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2013-01-12
VANDENBERG AFB, Calif. – The Landsat Data Continuity Mission, or LDCM, spacecraft stands in the Astrotech processing facility at Vandenberg Air Force Base in Calif., during fueling operations. The Landsat Data Continuity Mission is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: VAFB
2012-12-21
VANDENBERG AFB, Calif. -- Technicians unload and rotate NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians use a crane to move NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- NASA's Landsat Data Continuity Mission, or LDCM, satellite arrives by transport truck at Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians use a crane to move NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- NASA's Landsat Data Continuity Mission, or LDCM, satellite arrives by transport truck at Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- The truck transporting NASA's Landsat Data Continuity Mission, or LDCM, satellite backs into the processing facility at Vandenberg Air Force Base, Calif. for prelaunch checkout. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians begin checkout of NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- Technicians unload NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- Technicians inspect NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians unload NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians use a crane to move NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- Technicians position the transport container with NASA's Landsat Data Continuity Mission, or LDCM, satellite at the prelaunch processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- NASA's Landsat Data Continuity Mission, or LDCM, satellite arrives by transport truck at the Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- NASA's Landsat Data Continuity Mission, or LDCM, satellite during post-arrival inspections at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- The truck transporting NASA's Landsat Data Continuity Mission, or LDCM, satellite backs into the processing facility at Vandenberg Air Force Base, Calif. for prelaunch checkout. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif.-- Technicians begin checkout of NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- Technicians unload NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- Technicians position the transport container with NASA's Landsat Data Continuity Mission, or LDCM, satellite at the prelaunch processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- NASA's Landsat Data Continuity Mission, or LDCM, satellite during post-arrival inspections at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-21
VANDENBERG AFB, Calif. -- Technicians inspect NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
The impact of high-resolution topography on landslide characterization using DInSAR
NASA Astrophysics Data System (ADS)
Tiampo, K. F.; Barba, M.; Jacquemart, M. F.; Willis, M. J.; González, P. J.; McKee, C.; Samsonov, S. V.; Feng, W.
2017-12-01
Differential interferometric synthetic aperture radar (DInSAR) can measure surface deformation at the centimeter level and, as a result, has been used to investigate a wide variety of natural hazards since the 1990s. In general, short spatial and temporal baselines are selected to reduce decorrelation and the effect of incorrect removal of the topographic component in differential interferograms. The nearly global coverage of the Shuttle Radar Topography Mission (SRTM) digital elevation models (DEMs) significantly simplified and improved the modelling and removal of topography for differential interferometric applications. However, DEMs are produced today at much finer resolutions, although with varying availability and cost. SRTM DEMs are freely available at 30 m resolution world-wide and 10 m resolution in the US. The TanDEM-X mission has produced a worldwide DEM at 12 m, although it is not generally free of cost. Light Detection and Ranging (LiDAR) DEMs can provide better than 1m resolution, but are expensive to produce over limited extents. Finally, DEMs from optical data can be produced from Digital Globe satellite images over larger regions at resolutions of less than 1 m, subject to various restrictions. It can be shown that the coherence quality of a DInSAR image is directly related to the DEM resolution, improving recovery of the differential phase by significantly reducing the geometric decorrelation, and that the number of recovered pixels significantly increases with higher resolutions, particularly in steep topography. In this work we quantify that improvement for varying resolutions, from 1 to 30 m, and slopes and investigate its effect on the characterization of landslides in different regions and with a variety of surface conditions, including Greenland, Alaska, California, and the Canary Islands.
NASA Astrophysics Data System (ADS)
Barre, J.; Edwards, D. P.; Gaubert, B.; Worden, H. M.; Arellano, A. F.; Anderson, J. L.
2015-12-01
Current satellite observations of tropospheric composition made from low Earth orbit provide at best one or two measurements each day at any given location. Comparisons of Terra/MOPITT carbon monoxide (CO) and IASI/Metop CO observation assimilations will be presented. We use the DART Ensemble Adjustment Kalman Filter to assimilate observations in the CAM-Chem global chemistry-climate model. Data assimilation impacts due to both different instrument capabilities (i.e. vertical sensitivity and global coverage) will be discussed. Coverage is global but sparse, often with large uncertainties in individual measurements that limit examination of local and regional atmospheric composition over short time periods. This has hindered the operational uptake of these data for monitoring air quality and population exposure, and for initializing and evaluating chemical weather forecasts. By the end of the current decade there are planned geostationary Earth orbit (GEO) satellite missions for atmospheric composition over North America, East Asia and Europe with additional missions proposed. Together, these present the possibility of a constellation of geostationary platforms to achieve continuous time-resolved high-density observations of continental domains for mapping pollutant sources and variability on diurnal and local scales. We describe Observing System Simulation Experiments (OSSEs) to evaluate the contributions of these GEO missions to improve knowledge of near-surface air pollution due to intercontinental long-range transport and quantify chemical precursor emissions. Our approach uses an efficient computational method to sample a high-resolution global GEOS-5 chemistry Nature Run over each geographical region of the GEO constellation. The demonstration carbon monoxide (CO) observation simulator, which will be expanded to other chemical pollutants, currently produces multispectral retrievals (MOPITT-like) and captures realistic scene-dependent variation in measurement vertical sensitivity and cloud cover. The impact of observing over each region is evaluated independently. Winter and summer cases studies are investigated i.e. where emissions, cloud cover and CO lifetime significantly change.
NASA Technical Reports Server (NTRS)
Kurtz, Nathan T.; Markus, Thorsten; Cavalieri, Donald J.; Sparling, Lynn C.; Krabill, William B.; Gasiewski, Albin J.; Sonntag, John G.
2009-01-01
Combinations of sea ice freeboard and snow depth measurements from satellite data have the potential to provide a means to derive global sea ice thickness values. However, large differences in spatial coverage and resolution between the measurements lead to uncertainties when combining the data. High resolution airborne laser altimeter retrievals of snow-ice freeboard and passive microwave retrievals of snow depth taken in March 2006 provide insight into the spatial variability of these quantities as well as optimal methods for combining high resolution satellite altimeter measurements with low resolution snow depth data. The aircraft measurements show a relationship between freeboard and snow depth for thin ice allowing the development of a method for estimating sea ice thickness from satellite laser altimetry data at their full spatial resolution. This method is used to estimate snow and ice thicknesses for the Arctic basin through the combination of freeboard data from ICESat, snow depth data over first-year ice from AMSR-E, and snow depth over multiyear ice from climatological data. Due to the non-linear dependence of heat flux on ice thickness, the impact on heat flux calculations when maintaining the full resolution of the ICESat data for ice thickness estimates is explored for typical winter conditions. Calculations of the basin-wide mean heat flux and ice growth rate using snow and ice thickness values at the 70 m spatial resolution of ICESat are found to be approximately one-third higher than those calculated from 25 km mean ice thickness values.
High resolution wetland mapping in West Siberian taiga zone for methane emission inventory
NASA Astrophysics Data System (ADS)
Terentieva, I. E.; Glagolev, M. V.; Lapshina, E. D.; Sabrekov, A. F.; Maksyutov, S. S.
2015-12-01
High latitude wetlands are important for understanding climate change risks because these environments sink carbon and emit methane. Fine scale heterogeneity of wetland landscapes pose challenges for producing the greenhouse gas flux inventories based on point observations. To reduce uncertainties at the regional scale, we mapped wetlands and water bodies in the taiga zone of West Siberia on a scene-by-scene basis using a supervised classification of Landsat imagery. The training dataset was based on high-resolution images and field data that were collected at 28 test areas. Classification scheme was aimed at methane inventory applications and included 7 wetland ecosystem types composing 9 wetland complexes in different proportions. Accuracy assessment based on 1082 validation polygons of 10 × 10 pixels indicated an overall map accuracy of 79 %. The total area of the wetlands and water bodies was estimated to be 52.4 Mha or 4-12 % of the global wetland area. Ridge-hollow complexes prevail in WS's taiga, occupying 33 % of the domain, followed by forested bogs or "ryams" (23 %), ridge-hollow-lake complexes (16 %), open fens (8 %), palsa complexes (7 %), open bogs (5 %), patterned fens (4 %), and swamps (4 %). Various oligotrophic environments are dominant among the wetland ecosystems, while fens cover only 14 % of the area. Because of the significant update in the wetland ecosystem coverage, a considerable revaluation of the total CH4 emissions from the entire region is expected. A new Landsat-based map of WS's taiga wetlands provides a benchmark for validation of coarse-resolution global land cover products and wetland datasets in high latitudes.
Global CO2 Distributions over Land from the Greenhouse Gases Observing Satellite (GOSAT)
NASA Technical Reports Server (NTRS)
Hammerling, Dorit M.; Michalak, Anna M.; O'Dell, Christopher; Kawa, Randolph S.
2012-01-01
January 2009 saw the successful launch of the first space-based mission specifically designed for measuring greenhouse gases, the Japanese Greenhouse gases Observing SATellite (GOSAT). We present global land maps (Level 3 data) of column-averaged CO2 concentrations (X(sub CO2)) derived using observations from the GOSAT ACOS retrieval algorithm, for July through December 2009. The applied geostatistical mapping approach makes it possible to generate maps at high spatial and temporal resolutions that include uncertainty measures and that are derived directly from the Level 2 observations, without invoking an atmospheric transport model or estimates of CO2 uptake and emissions. As such, they are particularly well suited for comparison studies. Results show that the Level 3 maps for July to December 2009 on a lO x 1.250 grid, at six-day resolution capture much of the synoptic scale and regional variability of X(sub CO2), in addition to its overall seasonality. The uncertainty estimates, which reflect local data coverage, X(sub CO2) variability, and retrieval errors, indicate that the Southern latitudes are relatively well-constrained, while the Sahara Desert and the high Northern latitudes are weakly-constrained. A probabilistic comparison to the PCTM/GEOS-5/CASA-GFED model reveals that the most statistically significant discrepancies occur in South America in July and August, and central Asia in September to December. While still preliminary, these results illustrate the usefulness of a high spatiotemporal resolution, data-driven Level 3 data product for direct interpretation and comparison of satellite observations of highly dynamic parameters such as atmospheric CO2.
NASA Astrophysics Data System (ADS)
Gregg, T. K.; Bulmer, M. H.
1999-06-01
Exploration of the Martian surface with a rover is similar to investigation of Earth's oceans using remotely operated vehicles (ROVs) or deep submergence vehicles (DSVs). In the case of Mars, the techniques required to perform a robust scientific survey are similar to those that have been developed by the deep ocean research community. In both instances, scientists are challenged by having to choose and characterize a target site, identify favorable sites for detailed analysis and possible sample collection, only being able to maneuver within a few meters of the landing site and integrating data sets with a range of spatial resolutions that span 1-2 orders of magnitude (rover data versus satellite data, or submersible data versus bathymetric data). In the search for biologic communities at Earth's mid-ocean ridges, it is important to note that the vast majority of the terrain is completely barren of life: no microbes live in the thousands to hundreds of thousands of meters that separate the life-sustaining hydrothermal vent fields. In attempts to better understanding the origin and emplacement of geologic and biologic features on the seafloor, techniques have been developed to select sites of special interest (target sites), by combining the low-resolution, high spatial-coverage data with medium-resolution, higher spatial-coverage data. Once individual sites are selected, then a DSV or ROV is used to obtain high-resolution, low-spatial-coverage data. By integrating the different resolution data sets, the individual target sites can be placed into the larger context of the regional and global geologic system. Methods of exploration of the oceans are pertinent to the Mars Lander Missions because they highlight the importance and value of the acquisition of 'context' images. Over 60% of Earth's mid-ocean ridge crests have been surveyed using multibeam bathymetry. The typical resolution of such data is 100 m in the vertical and 20 m in the horizontal. This data set is comparable to the Viking Orbiter images of Mars. Only 7% of Earth's seafloor has been imaged using side-scan sonar systems which are towed behind a surface ship at an altitude of approx. 20 m to 200 m above the seafloor. This data set provides textural information on the target surface. The resolution of these instruments varies from 50 m for GLORIA to 1 m across and 2-4 m in the vertical for the DSL-120. Higher resolution is provided by camera sleds such as ARGO II, which is towed at altitudes of about 3 - 15 m above the seafloor. Videos on these instrument platforms can provide continuous real-time video imagery via a fiber-optic tether. Still and video photographic and digital images are typically collected every approx. 10 - 15 seconds. The typical field of view of images from these cameras is 5 m. Added flexibility is provided when DSVs such as Alvin are used since they are capable of more autonomous exploration and can collect and return samples.
Soil Moisture Active Passive (SMAP) Data and Services at the NASA DAACs
NASA Astrophysics Data System (ADS)
Leon, A.; Allen, A. R.; Leslie, S. R.
2014-12-01
The NASA Soil Moisture Active Passive (SMAP) mission will provide a capability for global mapping of soil moisture and freeze/thaw state with unprecedented accuracy, resolution, and coverage. The SMAP instrument includes both a radiometer and a synthetic aperture radar (SAR) operating at the L-band (1.20-1.41 GHz) and will provide global coverage at the equator every 3 days. The SMAP mission will play a critical role in understanding the Earth's water and energy cycles, improving weather and climate forecasting, and developing disaster prediction and monitoring services. The NASA Distributed Active Archive Centers (DAACs) at the Alaska Satellite Facility (ASF) and the National Snow and Ice Data Center (NSIDC) will jointly distribute and support SMAP data products. The DAACs will draw upon their unique expertise - ASF with SAR data and NSIDC with cryospheric and remotely-sensed soil moisture data- as well as their shared technologies to provide synergistic data access and support for SMAP products. In an effort to educate and broaden the SMAP user community, we will present an overview of the SMAP data products as well as when they will be available at the DAACs. NASA DAACs play an integral role in enabling data discovery and usage through the value-adding services they provide. Through this presentation, we will also discuss the tools and services at the ASF and NSIDC DAACs and gain further insight into how the DAACs can enable the user community to seamlessly and effectively utilize SMAP data in their research and applications.
NASA Technical Reports Server (NTRS)
Geogdzhayev, Igor V.; Cairns, Brian; Mishchenko, Michael I.; Tsigaridis, Kostas; van Noije, Twan
2014-01-01
To evaluate the effect of sampling frequency on the global monthly mean aerosol optical thickness (AOT), we use 6 years of geographical coordinates of Moderate Resolution Imaging Spectroradiometer (MODIS) L2 aerosol data, daily global aerosol fields generated by the Goddard Institute for Space Studies General Circulation Model and the chemical transport models Global Ozone Chemistry Aerosol Radiation and Transport, Spectral Radiationtransport Model for Aerosol Species and Transport Model 5, at a spatial resolution between 1.125 deg × 1.125 deg and 2 deg × 3?: the analysis is restricted to 60 deg S-60 deg N geographical latitude. We found that, in general, the MODIS coverage causes an underestimate of the global mean AOT over the ocean. The long-term mean absolute monthly difference between all and dark target (DT) pixels was 0.01-0.02 over the ocean and 0.03-0.09 over the land, depending on the model dataset. Negative DT biases peak during boreal summers, reaching 0.07-0.12 (30-45% of the global long-term mean AOT). Addition of the Deep Blue pixels tempers the seasonal dependence of the DT biases and reduces the mean AOT difference over land by 0.01-0.02. These results provide a quantitative measure of the effect the pixel exclusion due to cloud contamination, ocean sun-glint and land type has on the MODIS estimates of the global monthly mean AOT. We also simulate global monthly mean AOT estimates from measurements provided by pixel-wide along-track instruments such as the Aerosol Polarimetry Sensor and the Cloud-Aerosol LiDAR with Orthogonal Polarization. We estimate the probable range of the global AOT standard error for an along-track sensor to be 0.0005-0.0015 (ocean) and 0.0029-0.01 (land) or 0.5-1.2% and 1.1-4% of the corresponding global means. These estimates represent errors due to sampling only and do not include potential retrieval errors. They are smaller than or comparable to the published estimate of 0.01 as being a climatologically significant change in the global mean AOT, suggesting that sampling density is unlikely to limit the use of such instruments for climate applications at least on a global, monthly scale.
Mid-Infrared OPO for High Resolution Measurements of Trace Gases in the Mars Atmosphere
NASA Technical Reports Server (NTRS)
Yu, Anthony W.; Numata,Kenji; Riris, haris; Abshire, James B.; Allan, Graham; Sun, Xiaoli; Krainak, Michael A.
2008-01-01
The Martian atmosphere is composed primarily (>95%) of CO2 and N2 gas, with CO, O2, CH4, and inert gases such as argon comprising most of the remainder. It is surprisingly dynamic with various processes driving changes in the distribution of CO2, dust, haze, clouds and water vapor on global scales in the meteorology of Mars atmosphere [I]. The trace gases and isotopic ratios in the atmosphere offer important but subtle clues as to the origins of the planet's atmosphere, hydrology, geology, and potential for biology. In the search for life on Mars, an important process is the ability of bacteria to metabolize inorganic substrates (H2, CO2 and rock) to derive energy and produce methane as a by-product of anaerobic metabolism. Trace gases have been measured in the Mars atmosphere from Earth, Mars orbit, and from the Mars surface. The concentration of water vapor and various carbon-based trace gases are observed in variable concentrations. Within the past decade multiple groups have reported detection of CH4, with concentrations in the 10's of ppb, using spectroscopic observations from Earth [2]. Passive spectrometers in the mid-infrared (MIR) are restricted to the sunlit side of the planet, generally in the mid latitudes, and have limited spectral and spatial resolution. To accurately map the global distribution and to locate areas of possibly higher concentrations of these gases such as plumes or vents requires an instrument with high sensitivity and fine spatial resolution that also has global coverage and can measure during both day and night. Our development goal is a new MIR lidar capable of measuring, on global scales, with sensitivity, resolution and precision needed to characterize the trace gases and isotopic ratios of the Martian atmosphere. An optical parametric oscillator operating in the MIR is well suited for this instrument. The sufficient wavelength tuning range of the OPO can extend the measurements to other organic molecules, CO2, atmospheric water vapor, clouds, temperature, dust, and aerosols, as well as possibly polar-cap properties. Our OPO-approach may allow a new capability for active remote sensing of the outer planets and moons, where the weaker sunlight further limit passive instruments. Here we report on the OPO development effort for this lidar instrument.
Till, Brian M; Peters, Alexander W; Afshar, Salim; Meara, John
2017-01-01
Blockchain technology and cryptocurrencies could remake global health financing and usher in an era global health equity and universal health coverage. We outline and provide examples for at least four important ways in which this potential disruption of traditional global health funding mechanisms could occur: universal access to financing through direct transactions without third parties; novel new multilateral financing mechanisms; increased security and reduced fraud and corruption; and the opportunity for open markets for healthcare data that drive discovery and innovation. We see these issues as a paramount to the delivery of healthcare worldwide and relevant for payers and providers of healthcare at state, national and global levels; for government and non-governmental organisations; and for global aid organisations, including the WHO, International Monetary Fund and World Bank Group.
NASA Astrophysics Data System (ADS)
Meng, Xia; Garay, Michael J.; Diner, David J.; Kalashnikova, Olga V.; Xu, Jin; Liu, Yang
2018-05-01
Research efforts to better characterize the differential toxicity of PM2.5 (particles with aerodynamic diameters less than or equal to 2.5 μm) speciation are often hindered by the sparse or non-existent coverage of ground monitors. The Multi-angle Imaging SpectroRadiometer (MISR) aboard NASA's Terra satellite is one of few satellite aerosol sensors providing information of aerosol shape, size and extinction globally for a long and continuous period that can be used to estimate PM2.5 speciation concentrations since year 2000. Currently, MISR only provides a 17.6 km product for its entire mission with global coverage every 9 days, a bit too coarse for air pollution health effects research and to capture local spatial variability of PM2.5 speciation. In this study, generalized additive models (GAMs) were developed using MISR prototype 4.4 km-resolution aerosol data with meteorological variables and geographical indicators, to predict ground-level concentrations of PM2.5 sulfate, nitrate, organic carbon (OC) and elemental carbon (EC) in Southern California between 2001 and 2015 at the daily level. The GAMs are able to explain 66%, 62%, 55% and 58% of the daily variability in PM2.5 sulfate, nitrate, OC and EC concentrations during the whole study period, respectively. Predicted concentrations capture large regional patterns as well as fine gradients of the four PM2.5 species in urban areas of Los Angeles and other counties, as well as in the Central Valley. This study is the first attempt to use MISR prototype 4.4 km-resolution AOD (aerosol optical depth) components data to predict PM2.5 sulfate, nitrate, OC and EC concentrations at the sub-regional scale. In spite of its low temporal sampling frequency, our analysis suggests that the MISR 4.4 km fractional AODs provide a promising way to capture the spatial hotspots and long-term temporal trends of PM2.5 speciation, understand the effectiveness of air quality controls, and allow our estimated PM2.5 speciation data to be linked with common spatial units such as census tract or zip code in epidemiological studies. This modeling strategy needs to be validated in other regions when more MISR 4.4 km data becoming available in the future.
Rosinski, Alexander Anthony; Narine, Steven; Yamey, Gavin
2013-01-01
Background In 2010, diarrhea caused 0.75 million child deaths, accounting for nearly 12% of all under-five mortality worldwide. Many evidence-based interventions can reduce diarrhea mortality, including oral rehydration solution (ORS), zinc, and improved sanitation. Yet global coverage levels of such interventions remain low. A new scorecard of diarrhea control, showing how different countries are performing in their control efforts, could draw greater attention to the low coverage levels of proven interventions. Methods We conducted in-depth qualitative interviews with 21 experts, purposively sampled for their relevant academic or implementation expertise, to explore their views on (a) the value of a scorecard of global diarrhea control and (b) which indicators should be included in such a scorecard. We then conducted a ranking exercise in which we compiled a list of all 49 indicators suggested by the experts, sent the list to the 21 experts, and asked them to choose 10 indicators that they would include and 10 that they would exclude from such a scorecard. Finally, we created a “prototype” scorecard based on the 9 highest-ranked indicators. Results Key themes that emerged from coding the interview transcripts were: a scorecard could facilitate country comparisons; it could help to identify best practices, set priorities, and spur donor action; and it could help with goal-setting and accountability in diarrhea control. The nine highest ranking indicators, in descending order, were ORS coverage, rotavirus vaccine coverage, zinc coverage, diarrhea-specific mortality rate, diarrhea prevalence, proportion of population with access to improved sanitation, proportion with access to improved drinking water, exclusive breastfeeding coverage, and measles vaccine coverage. Conclusion A new scorecard of global diarrhea control could help track progress, focus prevention and treatment efforts on the most effective interventions, establish transparency and accountability, and alert donors and ministries of health to inadequacies in diarrhea control efforts. PMID:23874412
Conveying Global Circulation Patterns in HDTV
NASA Astrophysics Data System (ADS)
Gardiner, N.; Janowiak, J.; Kinzler, R.; Trakinski, V.
2006-12-01
The American Museum of Natural History has partnered with the National Centers for Environmental Prediction (NCEP) to educate general audiences about weather and climate using high definition video broadcasts built from half-hourly global mosaics of infrared (IR) data from five geostationary satellites. The dataset being featured was developed by NCEP to improve precipitation estimates from microwave data that have finer spatial resolution but poorer temporal coverage. The IR data span +/-60 degrees latitude and show circulation patterns at sufficient resolution to teach informal science center visitors about both weather and climate events and concepts. Design and editorial principles for this media program have been guided by lessons learned from production and annual updates of visualizations that cover eight themes in both biological and Earth system sciences. Two formative evaluations on two dates, including interviews and written surveys of 480 museum visitors ranging in age from 13 to over 60, helped refine the design and implementation of the weather and climate program and demonstrated that viewers understood the program's initial literacy objectives, including: (1) conveying the passage of time and currency of visualized data; (2) geographic relationships inherent to atmospheric circulation patterns; and (3) the authenticity of visualized data, i.e., their origin from earth-orbiting satellites. Surveys also indicated an interest and willingness to learn more about weather and climate principles and events. Expanded literacy goals guide ongoing, biweekly production and distribution of global cloud visualization pieces that reach combined audiences of approximately 10 million. Two more rounds of evaluation are planned over the next two years to assess the effectiveness of the media program in addressing these expanded literacy goals.
NASA Technical Reports Server (NTRS)
Franz, B. A.; Behrenfeld, M. J.; Siegel, D. A.; Werdell, P. J.
2014-01-01
Marine phytoplankton are responsible for roughly half the net primary production (NPP) on Earth, fixing atmospheric CO2 into food that fuels global ocean ecosystems and drives the ocean's biogeochemical cycles. Phytoplankton growth is highly sensitive to variations in ocean physical properties, such as upper ocean stratification and light availability within this mixed layer. Satellite ocean color sensors, such as the Sea-viewing Wide Field-of-view Sensor (SeaWiFS; McClain 2009) and Moderate Resolution Imaging Spectroradiometer (MODIS; Esaias 1998), provide observations of sufficient frequency and geographic coverage to globally monitor physically-driven changes in phytoplankton distributions. In practice, ocean color sensors retrieve the spectral distribution of visible solar radiation reflected upward from beneath the ocean surface, which can then be related to changes in the photosynthetic phytoplankton pigment, chlorophyll- a (Chla; measured in mg m-3). Here, global Chla data for 2013 are evaluated within the context of the 16-year continuous record provided through the combined observations of SeaWiFS (1997-2010) and MODIS on Aqua (MODISA; 2002-present). Ocean color measurements from the recently launched Visible and Infrared Imaging Radiometer Suite (VIIRS; 2011-present) are also considered, but results suggest that the temporal calibration of the VIIRS sensor is not yet sufficiently stable for quantitative global change studies. All MODISA (version 2013.1), SeaWiFS (version 2010.0), and VIIRS (version 2013.1) data presented here were produced by NASA using consistent Chla algorithms.
NASA Astrophysics Data System (ADS)
Turtle, E. P.; McEwen, A. S.; Collins, G. C.; Fletcher, L. N.; Hansen, C. J.; Hayes, A.; Hurford, T., Jr.; Kirk, R. L.; Barr, A.; Nimmo, F.; Patterson, G.; Quick, L. C.; Soderblom, J. M.; Thomas, N.
2015-12-01
The Europa Imaging System will transform our understanding of Europa through global decameter-scale coverage, three-dimensional maps, and unprecedented meter-scale imaging. EIS combines narrow-angle and wide-angle cameras (NAC and WAC) designed to address high-priority Europa science and reconnaissance goals. It will: (A) Characterize the ice shell by constraining its thickness and correlating surface features with subsurface structures detected by ice penetrating radar; (B) Constrain formation processes of surface features and the potential for current activity by characterizing endogenic structures, surface units, global cross-cutting relationships, and relationships to Europa's subsurface structure, and by searching for evidence of recent activity, including potential plumes; and (C) Characterize scientifically compelling landing sites and hazards by determining the nature of the surface at scales relevant to a potential lander. The NAC provides very high-resolution, stereo reconnaissance, generating 2-km-wide swaths at 0.5-m pixel scale from 50-km altitude, and uses a gimbal to enable independent targeting. NAC observations also include: near-global (>95%) mapping of Europa at ≤50-m pixel scale (to date, only ~14% of Europa has been imaged at ≤500 m/pixel, with best pixel scale 6 m); regional and high-resolution stereo imaging at <1-m/pixel; and high-phase-angle observations for plume searches. The WAC is designed to acquire pushbroom stereo swaths along flyby ground-tracks, generating digital topographic models with 32-m spatial scale and 4-m vertical precision from 50-km altitude. These data support characterization of cross-track clutter for radar sounding. The WAC also performs pushbroom color imaging with 6 broadband filters (350-1050 nm) to map surface units and correlations with geologic features and topography. EIS will provide comprehensive data sets essential to fulfilling the goal of exploring Europa to investigate its habitability and perform collaborative science with other investigations, including cartographic and geologic maps, regional and high-resolution digital topography, GIS products, color and photometric data products, a geodetic control network tied to radar altimetry, and a database of plume-search observations.
NASA Technical Reports Server (NTRS)
Boardman, J. W.; Pieters, C. M.; Green, R. O.; Clark, R. N.; Sunshine, J.; Combe, J.-P.; Isaacson, P.; Lundeen, S. R.; Malaret, E.; McCord, T.;
2010-01-01
The Moon Mineralogy Mapper (M3), a NASA Discovery Mission of Opportunity, was launched October 22, 2008 from Shriharikota in India on board the Indian ISRO Chandrayaan- 1 spacecraft for a nominal two-year mission in a 100-km polar lunar orbit. M3 is a high-fidelity imaging spectrometer with 260 spectral bands in Target Mode and 85 spectral bands in a reduced-resolution Global Mode. Target Mode pixel sizes are nominally 70 meters and Global pixels (binned 2 by 2) are 140 meters, from the planned 100-km orbit. The mission was cut short, just before halfway, in August, 2009 when the spacecraft ceased operations. Despite the abbreviated mission and numerous technical and scientific challenges during the flight, M3 was able to cover more than 95% of the Moon in Global Mode. These data, presented and analyzed here as a global whole, are revolutionizing our understanding of the Moon. Already, numerous discoveries relating to volatiles and unexpected mineralogy have been published [1], [2], [3]. The rich spectral and spatial information content of the M3 data indicates that many more discoveries and an improved understanding of the mineralogy, geology, photometry, thermal regime and volatile status of our nearest neighbor are forthcoming from these data. Sadly, only minimal high-resolution Target Mode images were acquired, as these were to be the focus of the second half of the mission. This abstract gives the reader a global overview of all the M3 data that were collected and an introduction to their rich spectral character and complexity. We employ a Principal Components statistical method to assess the underlying dimensionality of the Moon as a whole, as seen by M3, and to identify numerous areas that are low-probability targets and thus of potential interest to selenologists.
NASA Technical Reports Server (NTRS)
Bell, Thomas L.; Lau, William K. M. (Technical Monitor)
2002-01-01
The proposed Global Precipitation Mission (GPM) builds on the success of the Tropical Rainfall Measuring Mission (TRMM), offering a constellation of microwave-sensor-equipped smaller satellites in addition to a larger, multiply-instrumented "mother" satellite that will include an improved precipitation radar system to which the precipitation estimates of the smaller satellites can be tuned. Coverage by the satellites will be nearly global rather than being confined as TRMM was to lower latitudes. It is hoped that the satellite constellation can provide observations at most places on the earth at least once every three hours, though practical considerations may force some compromises. The GPM system offers the possibility of providing precipitation maps with much better time resolution than the monthly averages around which TRMM was planned, and therefore opens up new possibilities for hydrology and data assimilation into models. In this talk, methods that were developed for estimating sampling error in the rainfall averages that TRMM is providing will be used to estimate sampling error levels for GPM-era configurations. Possible impacts on GPM products of compromises in the sampling frequency will be discussed.
GPS meteorology - Remote sensing of atmospheric water vapor using the Global Positioning System
NASA Technical Reports Server (NTRS)
Bevis, Michael; Businger, Steven; Herring, Thomas A.; Rocken, Christian; Anthes, Richard A.; Ware, Randolph H.
1992-01-01
We present a new approach to remote sensing of water vapor based on the Global Positioning System (GPS). Geodesists and geophysicists have devised methods for estimating the extent to which signals propagating from GPS satellites to ground-based GPS receivers are delayed by atmospheric water vapor. This delay is parameterized in terms of a time-varying zenith wet delay (ZWD) which is retrieved by stochastic filtering of the GPS data. Given surface temperature and pressure readings at the GPS receiver, the retrieved ZWD can be transformed with very little additional uncertainty into an estimate of the integrated water vapor (IWV) overlying that receiver. Networks of continuously operating GPS receivers are being constructed by geodesists, geophysicists, and government and military agencies, in order to implement a wide range of positioning capabilities. These emerging GPS networks offer the possibility of observing the horizontal distribution of IWV or, equivalently, precipitate water with unprecedented coverage and a temporal resolution of the order of 10 min. These measurements could be utilized in operational weather forecasting and in fundamental research into atmospheric storm systems, the hydrologic cycle, atmospheric chemistry, and global climate change.
An Overview of SIMBIOS Program Activities and Accomplishments. Chapter 1
NASA Technical Reports Server (NTRS)
Fargion, Giulietta S.; McClain, Charles R.
2003-01-01
The SIMBIOS Program was conceived in 1994 as a result of a NASA management review of the agency's strategy for monitoring the bio-optical properties of the global ocean through space-based ocean color remote sensing. At that time, the NASA ocean color flight manifest included two data buy missions, the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and Earth Observing System (EOS) Color, and three sensors, two Moderate Resolution Imaging Spectroradiometers (MODIS) and the Multi-angle Imaging Spectro-Radiometer (MISR), scheduled for flight on the EOS-Terra and EOS-Aqua satellites. The review led to a decision that the international assemblage of ocean color satellite systems provided ample redundancy to assure continuous global coverage, with no need for the EOS Color mission. At the same time, it was noted that non-trivial technical difficulties attended the challenge (and opportunity) of combining ocean color data from this array of independent satellite systems to form consistent and accurate global bio-optical time series products. Thus, it was announced at the October 1994 EOS Interdisciplinary Working Group meeting that some of the resources budgeted for EOS Color should be redirected into an intercalibration and validation program (McClain et al., 2002).
NASA Astrophysics Data System (ADS)
Long, Ying; Wood, Troy D.
2015-01-01
Most enzymatic microreactors for protein digestion are based on trypsin, but proteins with hydrophobic segments may be difficult to digest because of the paucity of Arg and Lys residues. Microreactors based on pepsin, which is less specific than trypsin, can overcome this challenge. Here, an integrated immobilized pepsin microreactor (IPMR)/nanoelectrospray emitter is examined for its potential for peptide mapping. For myoglobin, equivalent sequence coverage is obtained in a thousandth the time of solution digestion with better sequence coverage. While sequence coverage of cytochrome c is lesser than solution in this short duration, more highly-charged peptic peptides are produced and a number of peaks are unidentified at low-resolution, suggesting that high-resolution mass spectrometry is needed to take full advantage of integrated IPMR/nanoelectrospray devices.
Seismic imaging: From classical to adjoint tomography
NASA Astrophysics Data System (ADS)
Liu, Q.; Gu, Y. J.
2012-09-01
Seismic tomography has been a vital tool in probing the Earth's internal structure and enhancing our knowledge of dynamical processes in the Earth's crust and mantle. While various tomographic techniques differ in data types utilized (e.g., body vs. surface waves), data sensitivity (ray vs. finite-frequency approximations), and choices of model parameterization and regularization, most global mantle tomographic models agree well at long wavelengths, owing to the presence and typical dimensions of cold subducted oceanic lithospheres and hot, ascending mantle plumes (e.g., in central Pacific and Africa). Structures at relatively small length scales remain controversial, though, as will be discussed in this paper, they are becoming increasingly resolvable with the fast expanding global and regional seismic networks and improved forward modeling and inversion techniques. This review paper aims to provide an overview of classical tomography methods, key debates pertaining to the resolution of mantle tomographic models, as well as to highlight recent theoretical and computational advances in forward-modeling methods that spearheaded the developments in accurate computation of sensitivity kernels and adjoint tomography. The first part of the paper is devoted to traditional traveltime and waveform tomography. While these approaches established a firm foundation for global and regional seismic tomography, data coverage and the use of approximate sensitivity kernels remained as key limiting factors in the resolution of the targeted structures. In comparison to classical tomography, adjoint tomography takes advantage of full 3D numerical simulations in forward modeling and, in many ways, revolutionizes the seismic imaging of heterogeneous structures with strong velocity contrasts. For this reason, this review provides details of the implementation, resolution and potential challenges of adjoint tomography. Further discussions of techniques that are presently popular in seismic array analysis, such as noise correlation functions, receiver functions, inverse scattering imaging, and the adaptation of adjoint tomography to these different datasets highlight the promising future of seismic tomography.
Wei, Yaxing; Liu, Shishi; Huntzinger, Deborah N.; ...
2014-12-05
Ecosystems are important and dynamic components of the global carbon cycle, and terrestrial biospheric models (TBMs) are crucial tools in further understanding of how terrestrial carbon is stored and exchanged with the atmosphere across a variety of spatial and temporal scales. Improving TBM skills, and quantifying and reducing their estimation uncertainties, pose significant challenges. The Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal multi-scale and multi-model intercomparison effort set up to tackle these challenges. The MsTMIP protocol prescribes standardized environmental driver data that are shared among model teams to facilitate model model and model observation comparisons. Inmore » this article, we describe the global and North American environmental driver data sets prepared for the MsTMIP activity to both support their use in MsTMIP and make these data, along with the processes used in selecting/processing these data, accessible to a broader audience. Based on project needs and lessons learned from past model intercomparison activities, we compiled climate, atmospheric CO 2 concentrations, nitrogen deposition, land use and land cover change (LULCC), C3 / C4 grasses fractions, major crops, phenology and soil data into a standard format for global (0.5⁰ x 0.5⁰ resolution) and regional (North American: 0.25⁰ x 0.25⁰ resolution) simulations. In order to meet the needs of MsTMIP, improvements were made to several of the original environmental data sets, by improving the quality, and/or changing their spatial and temporal coverage, and resolution. The resulting standardized model driver data sets are being used by over 20 different models participating in MsTMIP. Lastly, the data are archived at the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC, http://daac.ornl.gov) to provide long-term data management and distribution.« less
Big Data and High-Performance Computing in Global Seismology
NASA Astrophysics Data System (ADS)
Bozdag, Ebru; Lefebvre, Matthieu; Lei, Wenjie; Peter, Daniel; Smith, James; Komatitsch, Dimitri; Tromp, Jeroen
2014-05-01
Much of our knowledge of Earth's interior is based on seismic observations and measurements. Adjoint methods provide an efficient way of incorporating 3D full wave propagation in iterative seismic inversions to enhance tomographic images and thus our understanding of processes taking place inside the Earth. Our aim is to take adjoint tomography, which has been successfully applied to regional and continental scale problems, further to image the entire planet. This is one of the extreme imaging challenges in seismology, mainly due to the intense computational requirements and vast amount of high-quality seismic data that can potentially be assimilated. We have started low-resolution inversions (T > 30 s and T > 60 s for body and surface waves, respectively) with a limited data set (253 carefully selected earthquakes and seismic data from permanent and temporary networks) on Oak Ridge National Laboratory's Cray XK7 "Titan" system. Recent improvements in our 3D global wave propagation solvers, such as a GPU version of the SPECFEM3D_GLOBE package, will enable us perform higher-resolution (T > 9 s) and longer duration (~180 m) simulations to take the advantage of high-frequency body waves and major-arc surface waves, thereby improving imbalanced ray coverage as a result of the uneven global distribution of sources and receivers. Our ultimate goal is to use all earthquakes in the global CMT catalogue within the magnitude range of our interest and data from all available seismic networks. To take the full advantage of computational resources, we need a solid framework to manage big data sets during numerical simulations, pre-processing (i.e., data requests and quality checks, processing data, window selection, etc.) and post-processing (i.e., pre-conditioning and smoothing kernels, etc.). We address the bottlenecks in our global seismic workflow, which are mainly coming from heavy I/O traffic during simulations and the pre- and post-processing stages, by defining new data formats for seismograms and outputs of our 3D solvers (i.e., meshes, kernels, seismic models, etc.) based on ORNL's ADIOS libraries. We will discuss our global adjoint tomography workflow on HPC systems as well as the current status of our global inversions.
The Earth Observing System Terra Mission
NASA Technical Reports Server (NTRS)
Kaufman, Yoram J.; Einaudi, Franco (Technical Monitor)
2000-01-01
Langley's remarkable solar and lunar spectra collected from Mt. Whitney inspired Arrhenius to develop the first quantitative climate model in 1896. After the launch in Dec. 16 1999, NASA's Earth Observing AM Satellite (EOS-Terra) will repeat Langley's experiment, but for the entire planet, thus pioneering a wide array of calibrated spectral observations from space of the Earth System. Conceived in response to real environmental problems, EOS-Terra, in conjunction with other international satellite efforts, will fill a major gap in current efforts by providing quantitative global data sets with a resolution better than 1 km on the physical, chemical and biological elements of the earth system. Thus, like Langley's data, EOS-Terra can revolutionize climate research by inspiring a new generation of climate system models and enable us to assess the human impact on the environment. In the talk I shall review the historical perspective of the Terra mission and the key new elements of the mission. We expect to have first images that demonstrate the most innovative capability from EOS Terra 5 instruments: MODIS - 1.37 micron cirrus cloud channel; 250m daily coverage for clouds and vegetation change; 7 solar channels for land and aerosol studies; new fire channels; Chlorophyll fluorescence; MISR - first 9 multi angle views of clouds and vegetation; MOPITT - first global CO maps and C114 maps; ASTER - Thermal channels for geological studies with 15-90 m resolution.
Registration and Fusion of Multiple Source Remotely Sensed Image Data
NASA Technical Reports Server (NTRS)
LeMoigne, Jacqueline
2004-01-01
Earth and Space Science often involve the comparison, fusion, and integration of multiple types of remotely sensed data at various temporal, radiometric, and spatial resolutions. Results of this integration may be utilized for global change analysis, global coverage of an area at multiple resolutions, map updating or validation of new instruments, as well as integration of data provided by multiple instruments carried on multiple platforms, e.g. in spacecraft constellations or fleets of planetary rovers. Our focus is on developing methods to perform fast, accurate and automatic image registration and fusion. General methods for automatic image registration are being reviewed and evaluated. Various choices for feature extraction, feature matching and similarity measurements are being compared, including wavelet-based algorithms, mutual information and statistically robust techniques. Our work also involves studies related to image fusion and investigates dimension reduction and co-kriging for application-dependent fusion. All methods are being tested using several multi-sensor datasets, acquired at EOS Core Sites, and including multiple sensors such as IKONOS, Landsat-7/ETM+, EO1/ALI and Hyperion, MODIS, and SeaWIFS instruments. Issues related to the coregistration of data from the same platform (i.e., AIRS and MODIS from Aqua) or from several platforms of the A-train (i.e., MLS, HIRDLS, OMI from Aura with AIRS and MODIS from Terra and Aqua) will also be considered.
NASA Technical Reports Server (NTRS)
Markus, Thorsten; Henrichs, John
2006-01-01
The Marginal sea Ice Zone (MIZ) and the sea ice edge are the most dynamic areas of the sea ice cover. Knowledge of the sea ice edge location is vital for routing shipping in the polar regions. The ice edge is the location of recurrent plankton blooms, and is the habitat for a number of animals, including several which are under severe ecological threat. Polar lows are known to preferentially form along the sea ice edge because of induced atmospheric baroclinicity, and the ice edge is also the location of both vertical and horizontal ocean currents driven by thermal and salinity gradients. Finally, sea ice is both a driver and indicator of climate change and monitoring the position of the ice edge accurately over long time periods enables assessment of the impact of global and regional warming near the poles. Several sensors are currently in orbit that can monitor the sea ice edge. These sensors, though, have different spatial resolutions, different limitations, and different repeat frequencies. Satellite passive microwave sensors can monitor the ice edge on a daily or even twice-daily basis, albeit with low spatial resolution - 25 km for the Special Sensor Microwave Imager (SSM/I) or 12.5 km for the Advanced Microwave Scanning Radiometer (AMSR-E). Although special methods exist that allow the detection of the sea ice edge at a quarter of that nominal resolution (PSSM). Visible and infrared data from the Advanced Very High Resolution Radiometer (AVHRR) and from the Moderate Resolution Imaging Spectroradiometer (MODIS) provide daily coverage at 1 km and 250 m, respectively, but the surface observations me limited to cloud-free periods. The Landsat 7 Enhanced Thematic Mapper (ETM+) has a resolution of 15 to 30 m but is limited to cloud-free periods as well, and does not provide daily coverage. Imagery from Synthetic Aperture Radar (SAR) instruments has resolutions of tens of meters to 100 m, and can be used to distinguish open water and sea ice on the basis of surface and volume scattering characteristics. The Canadian RADARSAT C-band SAR provides data that cover the Arctic Ocean and the MIZ every 3 days. A change-point detection approach was utilized to obtain an ice edge estimate from the RADARSAT data The Quickscat scatterometer provides ice edge information with a resolution of a few kilometers on a near-daily basis. During portions of March and April of 2003 a series of aircraft flights were conducted over the ice edge in the Bering Sea carrying the Polarimetric Scanning Radiometer (PSR), which provides spectral coverage identical with the AMSR-E instrument at a resolution of 500 meters. In this study we investigated these different data sets and analyzed differences in their definition of the sea ice edge and the marginal ice zone and how these differences as well as their individual limitations affect the monitoring of the ice edge dynamics. We also examined how the nature of the sea ice edge, including its location, compactness and shape, changes over the seasons. Our approach was based on calculation of distances between ice edges derived from the satellite and aircraft data sets listed above as well as spectral coherence methods and shape parameters such as tortuosity, curvature, and fractional dimension.
NASA Astrophysics Data System (ADS)
Nghiem, S. V.; Brakenridge, G. R.; Nguyen, D. T.
2017-12-01
Hurricane Harvey inflicted historical catastrophic flooding across extensive regions around Houston and southeast Texas after making landfall on 25 August 2017. The Federal Emergency Management Agency (FEMA) requested urgent supports for flood mapping and monitoring in an emergency response to the extreme flood situation. An innovative satellite remote sensing method, called the Depolarization Reduction Algorithm for Global Observations of inundatioN (DRAGON), has been developed and implemented for use with Sentinel synthetic aperture radar (SAR) satellite data at a resolution of 10 meters to identify, map, and monitor inundation including pre-existing water bodies and newly flooded areas. Results from this new method are hydrologically consistent and have been verified with known surface waters (e.g., coastal ocean, rivers, lakes, reservoirs, etc.), with clear-sky high-resolution WorldView images (where waves can be seen on surface water in inundated areas within a small spatial coverage), and with other flood maps from the consortium of Global Flood Partnership derived from multiple satellite datasets (including clear-sky Landsat and MODIS at lower resolutions). Figure 1 is a high-resolution (4K UHD) image of a composite inundation map for the region around Rosharon (in Brazoria County, south of Houston, Texas). This composite inundation map reveals extensive flooding on 29 August 2017 (four days after Hurricane Harvey made landfall), and the inundation was still persistent in most of the west and south of Rosharon one week later (5 September 2017) while flooding was reduced in the east of Rosharon. Hurricane Irma brought flooding to a number of areas in Florida. As of 10 September 2017, Sentinel SAR flood maps reveal inundation in the Florida Panhandle and over lowland surfaces on several islands in the Florida Keys. However, Sentinel SAR results indicate that flooding along the Florida coast was not extreme despite Irma was a Category-5 hurricane that might have inflicted a potentially strong storm surge. DRAGON flood mapping products over various regions in Texas and in Florida were provided to FEMA. Figure 1. Composite inundation map derived from Sentinel SAR data for the region around Rosharon on 9/5/2017 (orange), inundation on 8/29/2017 (yellow), and pre-existing surface waters on 8/5/2017 (blue).
Determining Titan surface topography from Cassini SAR data
Stiles, Bryan W.; Hensley, Scott; Gim, Yonggyu; Bates, David M.; Kirk, Randolph L.; Hayes, Alex; Radebaugh, Jani; Lorenz, Ralph D.; Mitchell, Karl L.; Callahan, Philip S.; Zebker, Howard; Johnson, William T.K.; Wall, Stephen D.; Lunine, Jonathan I.; Wood, Charles A.; Janssen, Michael; Pelletier, Frederic; West, Richard D.; Veeramacheneni, Chandini
2009-01-01
A technique, referred to as SARTopo, has been developed for obtaining surface height estimates with 10 km horizontal resolution and 75 m vertical resolution of the surface of Titan along each Cassini Synthetic Aperture Radar (SAR) swath. We describe the technique and present maps of the co-located data sets. A global map and regional maps of Xanadu and the northern hemisphere hydrocarbon lakes district are included in the results. A strength of the technique is that it provides topographic information co-located with SAR imagery. Having a topographic context vastly improves the interpretability of the SAR imagery and is essential for understanding Titan. SARTopo is capable of estimating surface heights for most of the SAR-imaged surface of Titan. Currently nearly 30% of the surface is within 100 km of a SARTopo height profile. Other competing techniques provide orders of magnitude less coverage. We validate the SARTopo technique through comparison with known geomorphological features such as mountain ranges and craters, and by comparison with co-located nadir altimetry, including a 3000 km strip that had been observed by SAR a month earlier. In this area, the SARTopo and nadir altimetry data sets are co-located tightly (within 5-10 km for one 500 km section), have similar resolution, and as expected agree closely in surface height. Furthermore the region contains prominent high spatial resolution topography, so it provides an excellent test of the resolution and precision of both techniques.
NASA Astrophysics Data System (ADS)
Saulskiy, V. K.
2005-01-01
Multisatellite systems with linear structure (SLS) are defined, and their application for a continuous global or zonal coverage of the Earth’s surface is justified. It is demonstrated that in some cases these systems turned out to be better than usually recommended kinematically regular systems by G.V. Mozhaev, delta systems of J.G. Walker, and polar systems suggested by F.W. Gobets, L. Rider, and W.S. Adams. When a comparison is made using the criterion of a minimum radius of one-satellite coverage circle, the SLS beat the other systems for the majority of satellite numbers from the range 20 63, if the global continuous single coverage of the Earth is required. In the case of a zonal continuous single coverage of the latitude belt ±65°, the SLS are preferable at almost all numbers of satellites from 38 to 100, and further at any values up to 200 excluding 144.
Ooms, G; Marten, R; Waris, A; Hammonds, R; Mulumba, M; Friedman, E A
2014-02-01
Establishing a reform agenda for the World Health Organization (WHO) requires understanding its role within the wider global health system and the purposes of that wider global health system. In this paper, the focus is on one particular purpose: achieving universal health coverage (UHC). The intention is to describe why achieving UHC requires something like a Framework Convention on Global Health (FCGH) that have been proposed elsewhere,(1) why WHO is in a unique position to usher in an FCGH, and what specific reforms would help enable WHO to assume this role. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Operational satellites and the global monitoring of snow and ice
NASA Technical Reports Server (NTRS)
Walsh, John E.
1991-01-01
The altitudinal dependence of the global warming projected by global climate models is at least partially attributable to the albedo-temperature feedback involving snow and ice, which must be regarded as key variables in the monitoring for global change. Statistical analyses of data from IR and microwave sensors monitoring the areal coverage and extent of sea ice have led to mixed conclusions about recent trends of hemisphere sea ice coverage. Seasonal snow cover has been mapped for over 20 years by NOAA/NESDIS on the basis of imagery from a variety of satellite sensors. Multichannel passive microwave data show some promise for the routine monitoring of snow depth over unforested land areas.
Atmospheric Science Data Center
2018-04-12
SSE Global Data Text files of monthly averaged data for the entire ... Version: V6 Location: Global Spatial Coverage: (90N, 90S)(180W,180E) ... File Format: ASCII Order Data: SSE Global Data: Order Data SCAR-B Block: ...
Till, Brian M; Peters, Alexander W; Afshar, Salim; Meara, John G
2017-01-01
Blockchain technology and cryptocurrencies could remake global health financing and usher in an era global health equity and universal health coverage. We outline and provide examples for at least four important ways in which this potential disruption of traditional global health funding mechanisms could occur: universal access to financing through direct transactions without third parties; novel new multilateral financing mechanisms; increased security and reduced fraud and corruption; and the opportunity for open markets for healthcare data that drive discovery and innovation. We see these issues as a paramount to the delivery of healthcare worldwide and relevant for payers and providers of healthcare at state, national and global levels; for government and non-governmental organisations; and for global aid organisations, including the WHO, International Monetary Fund and World Bank Group. PMID:29177101
Overview of Global Monitoring of Terrestrial Chlorophyll Fluorescence from Space
NASA Technical Reports Server (NTRS)
Guanter, Luis; Zhang, Yongguang; Kohler, Philipp; Walther, Sophia; Frankenberg, Christian; Joiner, Joanna
2016-01-01
Despite the critical importance of photosynthesis for the Earth system, understanding how it is influenced by factors such as climate variability, disturbance history, and water or nutrient availability remains a challenge because of the complex interactions and the lack of GPP measurements at various temporal and spatial scales. Space observations of the sun-induced chlorophyll fluorescence (SIF) electromagnetic signal emitted by plants in the 650-850nm spectral range hold the promise of providing a new view of vegetation photosynthesis on a global basis. Global retrievals of SIF from space have recently been achieved from a number of spaceborne spectrometers originally intended for atmospheric research. Despite not having been designed for land applications, such instruments have turned out to provide the necessary spectral and radiometric sensitivity for SIF retrieval from space. The first global measurements of SIF were achieved in 2011 from spectra acquired by the Japanese GOSAT mission launched in 2009. The retrieval takes advantage of the high spectral resolution provided by GOSATs Fourier Transform Spectrometer (FTS) which allows the evaluation of the in-filling of solar Fraunhofer lines by SIF. Unfortunately, GOSAT only provides a sparse spatial sampling with individual soundings separated by several hundred kilometers. Complementary, the Global Ozone Monitoring Experiment-2 (GOME-2) instruments onboard MetOp-A and MetOp-B enable SIF retrievals since 2007 with a continuous and global spatial coverage. GOME-2 measures in the red and near-infrared (NIR) spectral regions with a spectral resolution of 0.5 nm and a pixel size of up to 40x40 km2. Most recently, another global and spatially continuous data set of SIF retrievals at 740 nm spanning the 2003-2012 time frame has been produced from ENVISATSCIAMACHY. This observational scenario has been completed by the first fluorescence data from the NASA-JPL OCO-2 mission (launched in July 2014) and the upcoming Copernicus' Sentinel 5-Precursor to be launched in early 2016. OCO-2 and TROPOMI offer the possibility of monitoring SIF globally with a 100-fold improvement in spatial and temporal resolution with respect to the current measurements from the GOSAT, GOME-2 and SCIAMACHY missions. In this contribution, we will provide an overview of existing global SIF data sets derived from space-based atmospheric spectrometers and will demonstrate the potential of such data to improve our knowledge of vegetation photosynthesis and gross primary production at the synoptic scale. We will show examples of ongoing research exploiting SIF data for an improved monitoring of photosynthetic activity in different ecosystems, including large crop belts worldwide, the Amazon rainforest and boreal evergreen forests.
State of equity: childhood immunization in the World Health Organization African Region.
Casey, Rebecca Mary; Hampton, Lee McCalla; Anya, Blanche-Philomene Melanga; Gacic-Dobo, Marta; Diallo, Mamadou Saliou; Wallace, Aaron Stuart
2017-01-01
In 2010, the Global Vaccine Action Plan called on all countries to reach and sustain 90% national coverage and 80% coverage in all districts for the third dose of diphtheria-tetanus-pertussis vaccine (DTP3) by 2015 and for all vaccines in national immunization schedules by 2020. The aims of this study are to analyze recent trends in national vaccination coverage in the World Health Organization African Region andto assess how these trends differ by country income category. We compared national vaccination coverage estimates for DTP3 and the first dose of measles-containing vaccine (MCV) obtained from the World Health Organization (WHO)/United Nations Children's Fund (UNICEF) joint estimates of national immunization coverage for all African Region countries. Using United Nations (UN) population estimates of surviving infants and country income category for the corresponding year, we calculated population-weighted average vaccination coverage by country income category (i.e., low, lower middle, and upper middle-income) for the years 2000, 2005, 2010 and 2015. DTP3 coverage in the African Region increased from 52% in 2000 to 76% in 2015,and MCV1 coverage increased from 53% to 74% during the same period, but with considerable differences among countries. Thirty-six African Region countries were low income in 2000 with an average DTP3 coverage of 50% while 26 were low income in 2015 with an average coverage of 80%. Five countries were lower middle-income in 2000 with an average DTP3 coverage of 84% while 12 were lower middle-income in 2015 with an average coverage of 69%. Five countries were upper middle-income in 2000 with an average DTP3 coverage of 73% and eight were upper middle-income in 2015 with an average coverage of 76%. Disparities in vaccination coverage by country persist in the African Region, with countries that were lower middle-income having the lowest coverage on average in 2015. Monitoring and addressing these disparities is essential for meeting global immunization targets.
A Commercial Architecture for Satellite Imagery
2006-09-01
incorporates image detection from the visible and near - infrared wavelengths, 3) 16 Ball Aerospace...present limited total area coverage since the field of regard is smallest. The opposite is true for resolution and total area coverage near apogee. The...27 B. SENSOR FIELD OF REGARD ...................................................................27 1. Spherical Analysis
Dual-comb spectroscopy of laser-induced plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bergevin, Jenna; Wu, Tsung-Han; Yeak, Jeremy
Dual-comb spectroscopy has become a powerful spectroscopic technique in applications that rely on its broad spectral coverage combined with high frequency resolution capabilities. Experiments to date have primarily focused on detection and analysis of multiple gas species under semi-static conditions, with applications ranging from environmental monitoring of greenhouse gases to high resolution molecular spectroscopy. Here, we utilize dual-comb spectroscopy to demonstrate broadband, high-resolution, and time-resolved measurements in a laser induced plasma for the first time. As a first demonstration, we simultaneously detect trace amounts of Rb and K in solid samples with a single laser ablation shot, with transitions separatedmore » by over 6 THz (13 nm) and spectral resolution sufficient to resolve isotopic and ground state hyperfine splittings of the Rb D2 line. This new spectroscopic approach offers the broad spectral coverage found in the powerful techniques of laser-induced breakdown spectroscopy (LIBS) while providing the high-resolution and accuracy of cw laser-based spectroscopies.« less
Online Visualization and Analysis of Merged Global Geostationary Satellite Infrared Dataset
NASA Technical Reports Server (NTRS)
Liu, Zhong; Ostrenga, D.; Leptoukh, G.; Mehta, A.
2008-01-01
The NASA Goddard Earth Sciences Data Information Services Center (GES DISC) is home of Tropical Rainfall Measuring Mission (TRMM) data archive. The global merged IR product also known as the NCEP/CPC 4-km Global (60 degrees N - 60 degrees S) IR Dataset, is one of TRMM ancillary datasets. They are globally merged (60 degrees N - 60 degrees S) pixel-resolution (4 km) IR brightness temperature data (equivalent blackbody temperatures), merged from all available geostationary satellites (GOES-8/10, METEOSAT-7/5 and GMS). The availability of data from METEOSAT-5, which is located at 63E at the present time, yields a unique opportunity for total global (60 degrees N- 60 degrees S) coverage. The GES DISC has collected over 8 years of the data beginning from February of 2000. This high temporal resolution dataset can not only provide additional background information to TRMM and other satellite missions, but also allow observing a wide range of meteorological phenomena from space, such as, mesoscale convection systems, tropical cyclones, hurricanes, etc. The dataset can also be used to verify model simulations. Despite that the data can be downloaded via ftp, however, its large volume poses a challenge for many users. A single file occupies about 70 MB disk space and there is a total of approximately 73,000 files (approximately 4.5 TB) for the past 8 years. In order to facilitate data access, we have developed a web prototype to allow users to conduct online visualization and analysis of this dataset. With a web browser and few mouse clicks, users can have a full access to over 8 year and over 4.5 TB data and generate black and white IR imagery and animation without downloading any software and data. In short, you can make your own images! Basic functions include selection of area of interest, single imagery or animation, a time skip capability for different temporal resolution and image size. Users can save an animation as a file (animated gif) and import it in other presentation software, such as, Microsoft PowerPoint. The prototype will be integrated into GIOVANNI and existing GIOVANNI capabilities, such as, data download, Google Earth KMZ, etc will be available. Users will also be able to access other data products in the GIOVANNI family.
CryoSat-2 altimetry derived Arctic bathymetry map: first results and validation
NASA Astrophysics Data System (ADS)
Andersen, O. B.; Abulaitijiang, A.; Cancet, M.; Knudsen, P.
2017-12-01
The Technical University of Denmark (DTU), DTU Space has been developing high quality high resolution gravity fields including the new highly accurate CryoSat-2 radar altimetry satellite data which extends the global coverage of altimetry data up to latitude 88°. With its exceptional Synthetic Aperture Radar (SAR) mode being operating throughout the Arctic Ocean, leads, i.e., the ocean surface heights, is used to retrieve the sea surface height with centimeter-level range precision. Combined with the long repeat cycle ( 369 days), i.e., dense cross-track coverage, the high-resolution Arctic marine gravity can be modelled using the CryoSat-2 altimetry. Further, the polar gap can be filled by the available ArcGP product, thus yielding the complete map of the Arctic bathymetry map. In this presentation, we will make use of the most recent DTU17 marine gravity, to derive the arctic bathymetry map using inversion based on best available hydrographic maps. Through the support of ESA a recent evaluation of existing hydrographic models of the Arctic Ocean Bathymetry models (RTOPO, GEBCO, IBCAO etc) and various inconsistencies have been identified and means to rectify these inconsistencies have been taken prior to perform the inversion using altimetry. Simultaneously DTU Space has been placing great effort on the Arctic data screening, filtering, and de-noising using various altimetry retracking solutions and classifications. All the pre-processing contributed to the fine modelling of Actic gravity map. Thereafter, the arctic marine gravity grids will eventually be translated (downward continuation operation) to a new altimetry enhanced Arctic bathymetry map using appropriate band-pass filtering.
Crop classification using temporal stacks of multispectral satellite imagery
NASA Astrophysics Data System (ADS)
Moody, Daniela I.; Brumby, Steven P.; Chartrand, Rick; Keisler, Ryan; Longbotham, Nathan; Mertes, Carly; Skillman, Samuel W.; Warren, Michael S.
2017-05-01
The increase in performance, availability, and coverage of multispectral satellite sensor constellations has led to a drastic increase in data volume and data rate. Multi-decadal remote sensing datasets at the petabyte scale are now available in commercial clouds, with new satellite constellations generating petabytes/year of daily high-resolution global coverage imagery. The data analysis capability, however, has lagged behind storage and compute developments, and has traditionally focused on individual scene processing. We present results from an ongoing effort to develop satellite imagery analysis tools that aggregate temporal, spatial, and spectral information and can scale with the high-rate and dimensionality of imagery being collected. We investigate and compare the performance of pixel-level crop identification using tree-based classifiers and its dependence on both temporal and spectral features. Classification performance is assessed using as ground-truth Cropland Data Layer (CDL) crop masks generated by the US Department of Agriculture (USDA). The CDL maps contain 30m spatial resolution, pixel-level labels for around 200 categories of land cover, but are however only available post-growing season. The analysis focuses on McCook county in South Dakota and shows crop classification using a temporal stack of Landsat 8 (L8) imagery over the growing season, from April through October. Specifically, we consider the temporal L8 stack depth, as well as different normalized band difference indices, and evaluate their contribution to crop identification. We also show an extension of our algorithm to map corn and soy crops in the state of Mato Grosso, Brazil.
An Alternative Approach of Coastal Sea-Level Observation from Remote Sensing Imageries
NASA Astrophysics Data System (ADS)
Peng, H. Y.; Tseng, K. H.; Chung-Yen, K.; Lin, T. H.; Liao, W. H.; Chen, C. F.
2017-12-01
Coastal sea level can be observed as waterline changes along a coastal digital elevation model (DEM). However, most global DEMs, such as the Shuttle Radar Topography Mission (SRTM) DEM with 30 m resolution, provide limited coverage over coastal area due to the impermeability of radar signal over water and the lack of low-tide coincidence. Therefore, we aim to extend to coverage of SRTM DEM for the determination of intertidal zone and to monitor sea-level changes along the entire coastline of Taiwan (>1200km). We firstly collect historical cloud-free images since the 1980s, including Landsat series, SPOT series and Sentinel-2, and then calculate the Modified Normalized Difference Water Index (MNDWI) to identify water pixels. After computing water appearance probability of each pixel, it is converted into actual elevation by introducing the DTU10 tide model for high tide and low tide boundaries. A coastal DEM of intertidal zone is reconstructed and the accuracy is at 50 cm level as compared with in situ DEM built by an unmanned aerial vehicle (UAV). Finally, we use this product to define the up-to-date intertidal zone and estimate sea-level changes by using remote sensing snapshots.
Enabling Technologies for High-accuracy Multiangle Spectropolarimetric Imaging from Space
NASA Technical Reports Server (NTRS)
Diner, David J.; Macenka, Steven A.; Seshndri, Suresh; Bruce, Carl E; Jau, Bruno; Chipman, Russell A.; Cairns, Brian; Christoph, Keller; Foo, Leslie D.
2004-01-01
Satellite remote sensing plays a major role in measuring the optical and radiative properties, environmental impact, and spatial and temporal distribution of tropospheric aerosols. In this paper, we envision a new generation of spaceborne imager that integrates the unique strengths of multispectral, multiangle, and polarimetric approaches, thereby achieving better accuracies in aerosol optical depth and particle properties than can be achieved using any one method by itself. Design goals include spectral coverage from the near-UV to the shortwave infrared; global coverage within a few days; intensity and polarimetric imaging simultaneously at multiple view angles; kilometer to sub-kilometer spatial resolution; and measurement of the degree of linear polarization for a subset of the spectral complement with an uncertainty of 0.5% or less. The latter requirement is technically the most challenging. In particular, an approach for dealing with inter-detector gain variations is essential to avoid false polarization signals. We propose using rapid modulation of the input polarization state to overcome this problem, using a high-speed variable retarder in the camera design. Technologies for rapid retardance modulation include mechanically rotating retarders, liquid crystals, and photoelastic modulators (PEMs). We conclude that the latter are the most suitable.
BOREAS RSS-10 TOMS Circumpolar One-Degree PAR Images
NASA Technical Reports Server (NTRS)
Dye, Dennis G.; Holben, Brent; Nickeson, Jaime (Editor); Hall, Forrest G. (Editor); Smith, David E. (Technical Monitor)
2000-01-01
The Boreal Ecosystem-Atmosphere Study (BOREAS) Remote Sensing Science (RSS)-10 team investigated the magnitude of daily, seasonal, and yearly variations of Photosynthetically Active Radiation (PAR) from ground and satellite observations. This data set contains satellite estimates of surface-incident PAR (400-700 nm, MJ/sq m) at one-degree spatial resolution. The spatial coverage is circumpolar from latitudes of 41 to 66 degrees north. The temporal coverage is from May through September for years 1979 through 1989. Eleven-year statistics are also provided: (1) mean, (2) standard deviation, and (3) coefficient of variation for 1979-89. The PAR estimates were derived from the global gridded ultraviolet reflectivity data product (average of 360, 380 nm) from the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS). Image mask data are provided for identifying the boreal forest zone, and ocean/land and snow/ice-covered areas. The data are available as binary image format data files. The PAR data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-13
VANDENBERG AFB, Calif. – The boattail element is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuation Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2013-01-12
VANDENBERG AFB, Calif. – A technician inspects the Landsat Data Continuity Mission, or LDCM, spacecraft in the Astrotech processing facility at Vandenberg Air Force Base in Calif., following fueling operations. The Landsat Data Continuity Mission is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: VAFB
2012-12-19
VANDENBERG AFB, Calif.-- Technicians check out the transport truck used to deliver NASA's Landsat Data Continuity Mission, or LDCM, satellite to Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-09
VANDENBERG AFB, Calif. – The first stage booster of a United Launch Alliance Atlas V is raised onto the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-12-19
VANDENBERG AFB, Calif.-- The Astrotech payload processing facility at Vandenberg Air Force Base, Calif. where NASA's Landsat Data Continuity Mission, or LDCM, satellite will be processed prior to launch. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-09
VANDENBERG AFB, Calif. – The first stage booster of a United Launch Alliance Atlas V is raised onto the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-12-19
VANDENBERG AFB, Calif.-- Technicians check out the transport truck used to deliver NASA's Landsat Data Continuity Mission, or LDCM, satellite to Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-09
VANDENBERG AFB, Calif. – Cranes raise the first stage booster of a United Launch Alliance Atlas V onto the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuation Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-12-19
VANDENBERG AFB, Calif.-- Technicians check out the transport truck used to deliver NASA's Landsat Data Continuity Mission, or LDCM, satellite to Vandenberg Air Force Base, Calif. for prelaunch processing. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-18
VANDENBERG AFB, Calif.-- Mechanical ground support equipment to be used in support of NASA's Landsat Data Continuity Mission, or LDCM, satellite arrives by transport truck at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-10
VANDENBERG AFB, Calif. – The interstage booster segment is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuation Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-09
VANDENBERG AFB, Calif. – The first stage booster of a United Launch Alliance Atlas V is raised onto the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuation Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-12-21
VANDENBERG AFB, Calif. -- Technicians unload and rotate NASA's Landsat Data Continuity Mission, or LDCM, satellite at the Astrotech processing facility at Vandenberg Air Force Base, Calif. The payload faring is seen on the left. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-12-19
VANDENBERG AFB, Calif.-- Technicians monitor activity as the transport container delivering NASA's Landsat Data Continuity Mission, or LDCM, satellite is lowered to the floor at the prelaunch processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2013-01-12
VANDENBERG AFB, Calif. – A technician inspects the Landsat Data Continuity Mission, or LDCM, spacecraft in the Astrotech processing facility at Vandenberg Air Force Base in Calif., following fueling operations. The Landsat Data Continuity Mission is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: VAFB
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-12
VANDENBERG AFB, Calif. – A Centaur upper stage is lifted onto the first stage booster of a United Launch Alliance Atlas V at the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-12-19
VANDENBERG AFB, Calif.-- The transport container with NASA's Landsat Data Continuity Mission, or LDCM, satellite has been delivered to the prelaunch processing facility at Vandenberg Air Force Base, Calif. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 11, 2013. For more information, visit: http://www.nasa.gov/mission_pages/landsat/main/index.html Photo credit: NASA
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-09
VANDENBERG AFB, Calif. – Technicians prepare to raise the first stage booster of a United Launch Alliance Atlas V onto the launch pad at Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission LDCM is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
2012-10-08
VANDENBERG AFB, Calif. – A truck moves the first stage booster of a United Launch Alliance Atlas V to Space Launch Complex-3E at Vandenberg Air Force Base, Calif. in preparation for the launch of the Landsat Data Continuity Mission. The Landsat Data Continuity Mission, or LDCM, is the future of Landsat satellites. It will continue to obtain valuable data and imagery to be used in agriculture, education, business, science, and government. The Landsat Program provides repetitive acquisition of high resolution multispectral data of the Earth's surface on a global basis. The data from the Landsat spacecraft constitute the longest record of the Earth's continental surfaces as seen from space. It is a record unmatched in quality, detail, coverage, and value. Launch is planned for Feb. 2013. Photo credit: NASA/Roy Allison
Reconstruction of Arctic surface temperature in past 100 years using DINEOF
NASA Astrophysics Data System (ADS)
Zhang, Qiyi; Huang, Jianbin; Luo, Yong
2015-04-01
Global annual mean surface temperature has not risen apparently since 1998, which is described as global warming hiatus in recent years. However, measuring of temperature variability in Arctic is difficult because of large gaps in coverage of Arctic region in most observed gridded datasets. Since Arctic has experienced a rapid temperature change in recent years that called polar amplification, and temperature risen in Arctic is faster than global mean, the unobserved temperature in central Arctic will result in cold bias in both global and Arctic temperature measurement compared with model simulations and reanalysis datasets. Moreover, some datasets that have complete coverage in Arctic but short temporal scale cannot show Arctic temperature variability for long time. Data Interpolating Empirical Orthogonal Function (DINEOF) were applied to fill the coverage gap of NASA's Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP 250km smooth) product in Arctic with IABP dataset which covers entire Arctic region between 1979 and 1998, and to reconstruct Arctic temperature in 1900-2012. This method provided temperature reconstruction in central Arctic and precise estimation of both global and Arctic temperature variability with a long temporal scale. Results have been verified by extra independent station records in Arctic by statistical analysis, such as variance and standard deviation. The result of reconstruction shows significant warming trend in Arctic in recent 30 years, as the temperature trend in Arctic since 1997 is 0.76°C per decade, compared with 0.48°C and 0.67°C per decade from 250km smooth and 1200km smooth of GISTEMP. And global temperature trend is two times greater after using DINEOF. The discrepancies above stress the importance of fully consideration of temperature variance in Arctic because gaps of coverage in Arctic cause apparent cold bias in temperature estimation. The result of global surface temperature also proves that global warming in recent years is not as slow as thought.
Accuracy and coverage of the modernized Polish Maritime differential GPS system
NASA Astrophysics Data System (ADS)
Specht, Cezary
2011-01-01
The DGPS navigation service augments The NAVSTAR Global Positioning System by providing localized pseudorange correction factors and ancillary information which are broadcast over selected marine reference stations. The DGPS service position and integrity information satisfy requirements in coastal navigation and hydrographic surveys. Polish Maritime DGPS system has been established in 1994 and modernized (in 2009) to meet the requirements set out in IMO resolution for a future GNSS, but also to preserve backward signal compatibility of user equipment. Having finalized installation of the new technology L1, L2 reference equipment performance tests were performed.The paper presents results of the coverage modeling and accuracy measuring campaign based on long-term signal analyses of the DGPS reference station Rozewie, which was performed for 26 days in July 2009. Final results allowed to verify the coverage area of the differential signal from reference station and calculated repeatable and absolute accuracy of the system, after the technical modernization. Obtained field strength level area and position statistics (215,000 fixes) were compared to past measurements performed in 2002 (coverage) and 2005 (accuracy), when previous system infrastructure was in operation.So far, no campaigns were performed on differential Galileo. However, as signals, signal processing and receiver techniques are comparable to those know from DGPS. Because all satellite differential GNSS systems use the same transmission standard (RTCM), maritime DGPS Radiobeacons are standardized in all radio communication aspects (frequency, binary rate, modulation), then the accuracy results of differential Galileo can be expected as a similar to DGPS.Coverage of the reference station was calculated based on unique software, which calculate the signal strength level based on transmitter parameters or field signal strength measurement campaign, done in the representative points. The software works based on Baltic sea vector map, ground electric parameters and models atmospheric noise level in the transmission band.
Estimating Carbon Storage and Sequestration by Urban Trees at Multiple Spatial Resolutions
NASA Astrophysics Data System (ADS)
Wu, J.; Tran, A.; Liao, A.
2010-12-01
Urban forests are an important component of urban-suburban environments. Urban trees provide not only a full range of social and psychological benefits to city dwellers, but also valuable ecosystem services to communities, such as removing atmospheric carbon dioxide, improving air quality, and reducing storm water runoff. There is an urgent need for developing strategic conservation plans for environmentally sustainable urban-suburban development based on the scientific understanding of the extent and function of urban forests. However, several challenges remain to accurately quantify various environmental benefits provided by urban trees, among which is to deal with the effect of changing spatial resolution and/or scale. In this study, we intended to examine the uncertainties of carbon storage and sequestration associated with the tree canopy coverage of different spatial resolutions. Multi-source satellite imagery data were acquired for the City of Fullerton, located in Orange County of California. The tree canopy coverage of the study area was classified at three spatial resolutions, ranging from 30 m (Landsat-5 Thematic Mapper), 15 m (Advanced Spaceborne Thermal Emission and Reflection Radiometer), to 2.5 m (QuickBird). We calculated the amount of carbon stored in the trees represented on the individual tree coverage maps and the annual carbon taken up by the trees with a model (i.e., CITYgreen) developed by the U.S. Forest Service. The results indicate that urban trees account for significant proportions of land cover in the study area even with the low spatial resolution data. The estimated carbon fixation benefits vary greatly depending on the details of land use and land cover classification. The extrapolation of estimation from the fine-resolution stand-level to the low-resolution landscape-scale will likely not preserve reasonable accuracy.
MULTI-RESOLUTION LAND CHARACTERISTICS FOR THE MID-ATLANTIC INTEGRATED ASSESMENT (MAIA) STUDY AREA
This data set is a Geographic Information System (GIS) coverage of the land use and land cover for the United States Environmental Protection Agency (USEPA) Mid-Atlantic Integrated Assessment (MAIA) Project region. The coverage was produced using 1988, 1989, 1991,1992, and 1993...
TES/Aura L3 Atmospheric Temperatures Daily V4 (TL3ATD)
Atmospheric Science Data Center
2018-05-09
... Platform: TES Aura L1B Nadir/Limb Spatial Coverage: 5.3 x 8.5 km nadir 37 x 23 km limb Spatial ... 0.5 x 5 km nadir 2.3 x 23 km limb Temporal Coverage: 08/22/2004 - present Temporal Resolution: ...
Summer Arctic ice concentrations and characteristics from SAR and SSM/I data
NASA Technical Reports Server (NTRS)
Comiso, Joey C.; Kwok, Ron
1993-01-01
The extent and concentration of the Summer minima provide indirect information about the long term ability of the perennial portion of the ice pack to survive the Arctic atmosphere and ocean system. Both active and passive microwave data were used with some success for monitoring the ice cover during the Summer, but they both suffer from similar problems caused by the presence of meltponding, surface wetness, flooding, and freeze/thaw cycles associated with periodic changes in surface air temperatures. A comparative analysis of ice conditions in the Arctic region using coregistered ERS-1 SAR (Synthetic Aperture Radar) and SSM/I (Special Sensor Microwave/Imager) data was made. The analysis benefits from complementary information from the two systems, the good spatial resolution of SAR data, and the good time resolution of and global coverage by SSM/I data. The results show that in many areas ice concentrations derived from SAR data are significantly different (usually higher) than those derived from passive microwave data. Additional insights about surface conditions can be inferred depending on the nature of the discrepancies.
Sentinel-5 instrument: status of design, performance, and development
NASA Astrophysics Data System (ADS)
Gühne, T.; Keim, C.; Bartsch, P.; Weiß, S.; Melf, M.; Seefelder, W.
2017-09-01
The Sentinel-5 instrument is currently under development by a consortium led by Airbus Defence and Space in the frame of the European Union Copernicus program. It is a customer furnished item to the MetOp Second Generation satellite platform, which will provide operational meteorological data for the coming decades. Mission objective of the Sentinel-5 is to monitor the composition of the Earth atmosphere for Copernicus Atmosphere Services by taking measurements of trace gases and aerosols impacting air quality and climate with high resolution and daily global coverage. Therefore the Sentinel-5 provides five dispersive spectrometers covering the UV-VIS (270…500 nm), NIR (685 …773 nm) and SWIR (1590…1675 and 2305…2385 nm) spectral bands with resolutions <=1nm. Spatially the Sentinel-5 provides a 108° field of view with a ground sampling of 7.5 x 7 km2 at Nadir. The development program is post PDR and the build-up of the industrial team is finalised. We report on the instrument architecture and design derived from the driving requirements, the predicted instrument performance, and the general status of the program.
Earth Radiation Imbalance from a Constellation of 66 Iridium Satellites: Technological Aspects
NASA Technical Reports Server (NTRS)
Wiscombe, W.; Chiu, C. J-Y.
2012-01-01
Iridium Communications Inc. is launching a new generation of polar orbiting communication satellites in 2015-2017. Iridium will provide a hosted payload bay on each of the 66 satellites (plus 6 in-space spares). This offers the potential for a paradigm shift in the way we measure Earth radiation imbalance from space, as well as massive cost savings. Because the constellation provides 24/7 global coverage, there is no need to account for diurnal cycle via extrapolations from uncalibrated narrowband geostationary imagers. And the spares can be rolled over to view the Sun and deep space, then transfer their calibration to the other members of the constellation during the frequent cross-overs. In part using simulations of the constellation viewing realistic Earth scenes, this presentation will address the technological aspects of such a constellation: (1) the calibration strategy; (2) the highly-accurate and stable radiometers for measuring outgoing flux; and (3) the GRACE-inspired algorithms for representing the outgoing flux field in spherical harmonics and thus achieving rv500-km spatial resolution and two-hour temporal resolution.
An assessment of long term ecosystem research activities across European socio-ecological gradients.
Metzger, M J; Bunce, R G H; van Eupen, M; Mirtl, M
2010-06-01
Integration of European long term ecosystem research (LTER) would provide important support for the management of the pan-European environment and ecosystems, as well as international policy commitments. This does require appropriate coverage of Europe and standardised frameworks and research methods between countries. Emerging interest in socio-ecological systems prompted the present assessment of the distribution of LTER activities across European socio-ecological gradients. This paper presents a European stratification with a 1 km(2) resolution, delineating 48 broad socio-ecological regions. The dataset is based on an existing biogeophysical stratification constructed using multivariate clustering of mainly climatic variables and a newly developed socio-economic stratification based on an economic density indicator. The coverage of European LTER facilities across the socio-ecological gradients is tested using this dataset. The analysis shows two strong biases in the present LTER effort. Firstly, urban and disturbed regions are consistently under-represented, illustrating a bias for traditional ecological research away from human activity. Secondly, the Mediterranean, for which some of the most extreme global change impacts are projected, is receiving comparatively little attention. Both findings can help guide future investment in the European LTER network - and especially in a Long Term Socio-Ecological Research (LTSER) component- to provide a more balanced coverage. This will provide better scientific understanding of pan-European environmental concerns and support the management of natural resources and international policy commitments in the European Union. (c) 2010 Elsevier Ltd. All rights reserved.
ArcticDEM Validation and Accuracy Assessment
NASA Astrophysics Data System (ADS)
Candela, S. G.; Howat, I.; Noh, M. J.; Porter, C. C.; Morin, P. J.
2017-12-01
ArcticDEM comprises a growing inventory Digital Elevation Models (DEMs) covering all land above 60°N. As of August, 2017, ArcticDEM had openly released 2-m resolution, individual DEM covering over 51 million km2, which includes areas of repeat coverage for change detection, as well as over 15 million km2 of 5-m resolution seamless mosaics. By the end of the project, over 80 million km2 of 2-m DEMs will be produced, averaging four repeats of the 20 million km2 Arctic landmass. ArcticDEM is produced from sub-meter resolution, stereoscopic imagery using open source software (SETSM) on the NCSA Blue Waters supercomputer. These DEMs have known biases of several meters due to errors in the sensor models generated from satellite positioning. These systematic errors are removed through three-dimensional registration to high-precision Lidar or other control datasets. ArcticDEM is registered to seasonally-subsetted ICESat elevations due its global coverage and high report accuracy ( 10 cm). The vertical accuracy of ArcticDEM is then obtained from the statistics of the fit to the ICESat point cloud, which averages -0.01 m ± 0.07 m. ICESat, however, has a relatively coarse measurement footprint ( 70 m) which may impact the precision of the registration. Further, the ICESat data predates the ArcticDEM imagery by a decade, so that temporal changes in the surface may also impact the registration. Finally, biases may exist between different the different sensors in the ArcticDEM constellation. Here we assess the accuracy of ArcticDEM and the ICESat registration through comparison to multiple high-resolution airborne lidar datasets that were acquired within one year of the imagery used in ArcticDEM. We find the ICESat dataset is performing as anticipated, introducing no systematic bias during the coregistration process, and reducing vertical errors to within the uncertainty of the airborne Lidars. Preliminary sensor comparisons show no significant difference post coregistration, suggesting that there is no sensor bias between platforms, and all data is suitable for analysis without further correction. Here we will present accuracy assessments, observations and comparisons over diverse terrain in parts of Alaska and Greenland.
Fox, Ashley M; Reich, Michael R
2015-10-01
Universal health coverage has recently become a top item on the global health agenda pressed by multilateral and donor organizations, as disenchantment grows with vertical, disease-specific health programs. This increasing focus on universal health coverage has brought renewed attention to the role of domestic politics and the interaction between domestic and international relations in the health reform process. This article proposes a theory-based framework for analyzing the politics of health reform for universal health coverage, according to four stages in the policy cycle (agenda setting, design, adoption, and implementation) and four variables that affect reform (interests, institutions, ideas, and ideology). This framework can assist global health policy researchers, multilateral organization officials, and national policy makers in navigating the complex political waters of health reforms aimed at achieving universal health coverage. To derive the framework, we critically review the theoretical and applied literature on health policy reform in developing countries and illustrate the framework with examples of health reforms moving toward universal coverage in low- and middle-income countries. We offer a series of lessons stemming from these experiences to date. Copyright © 2015 by Duke University Press.
NASA Astrophysics Data System (ADS)
Blount, W. K.; Hogue, T. S.; Franz, K.; Knipper, K. R.
2017-12-01
Accurate estimation of evapotranspiration (ET) is critical for the management of water resources, especially in water-stressed regions. ET accounts for approximately 60% of terrestrial precipitation globally and approaches 100% of annual rainfall in arid ecosystems, where transpiration becomes the dominant term. ET is difficult to measure due to its spatiotemporal variation, which requires adequate data coverage. While new remote sensing-based ET products are available at a 1 km spatial resolution, including the Operational Simplified Surface Energy Balance model (SSEBop) and the MODIS Global Evapotranspiration Project (MOD16), these products are available at monthly and 8-day temporal resolutions, respectively. To better understand the changing dynamics of hydrologic fluxes and the partitioning of water after land cover disturbances and to identify statically significant trends, more frequent observations are necessary. Utilizing the recently developed MODIS Soil Moisture-Evapotranspiration (MOD-SMET) model, daily temporal resolution is achieved. This presentation outlines the methodology of the MOD-SMET model and compares SSEBop, MOD16, and MOD-SMET ET estimates over the High Park Fire burn scar in Colorado, USA. MOD-SMET estimates are used to identify changes in fluxes and partitioning of the water cycle after a wildfire and during recovery in the High Park Fire near Fort Collins, Colorado. Initial results indicate greenness and ET from all three models decrease post-fire, with higher statistical confidence in high burn areas and spatial patterns that closely align with burn severity. MOD-SMET improves the ability to resolve statistically significant changes in ET following wildfires and better understand changes in the post-fire water budget. Utilizing this knowledge, water resource managers can better plan for, and mitigate, the short- and long-term impacts of wildfire on regional water supplies.
Calibrations and Comparisons of Aerosol Spectrometers linking Ground and Airborne Measurements
NASA Astrophysics Data System (ADS)
Williamson, C.; Brock, C. A.; Erdesz, F.
2015-12-01
The nucleation-mode aerosol size spectrometer (NMASS), a fast-time response instrument measuring aerosol size distributions between 5 and 60nm, is to sample in the boundary layer and free troposphere on NASA's Atmospheric Tomography mission (ATom), providing contiguous data with global coverage in all four seasons. In preparation for this the NMASS is calibrated for the expected flight conditions and compatibility studies are made with ground-based instrumentation. The NMASS is comprised of 5 parallel condensation particle counters (CPCs) using perfluoro-tributylamine as a working fluid. Understanding the variation of CPC counting efficiencies with respect to the chemical composition of the sample is important for accurate data analysis and can be used to give indirect information about sample chemical composition. This variation is strongly dependent on the working fluid. The absolute responses and associated variations of the NMASS to ammonium sulfate and limonene ozonolysis products, compounds pertinent to the composition of particles nucleated in the free troposphere and boundary later, are compared to those of butanol, diethylene-glycol and water based CPCs, which are more commonly used in ground-based measurements. While fast time-response is key to measuring aerosol size distributions on flights, high size-resolution is often prioritized for ground-based measurements, and so a scanning mobility particle sizer (SMPS) is commonly used. Inter-comparison between NMASS and SMPS data is non-trivial because of the different working principles and resolutions of the instruments and yet it is vital, for example, for understanding the sources of particles observed during flights and the global relevance of phenomena observed from field stations and in chambers. We report compatibility studies on inversions of data from the SMPS and NMASS, evaluating temporal and spatial resolution and sources of uncertainty.
NASA Astrophysics Data System (ADS)
Otis, D. B.; Muller-Karger, F. E.; Hestir, E.; Turpie, K. R.; Roberts, D. A.; Frouin, R.; Goodman, J.; Schaeffer, B. A.; Franz, B. A.; Humm, D. C.
2016-12-01
Coastal and inland waters and associated aquatic habitats, including wetlands, mangroves, submerged grasses, and coral reefs, are some of the most productive and diverse ecosystems on the planet. They provide services critical to human health, safety, and prosperity. Yet, they are highly vulnerable to changes in climate and other anthropogenic pressures. With a global population of over seven billion people and climbing, and a warming atmosphere driven by carbon dioxide now in excess of 400 ppb, these services are at risk of rapidly diminishing globally. We know little about how these ecosystems function. We need to characterize short-term changes in the functional biodiversity and biogeochemical cycles of these coastal and wetland ecosystems, from canopy to benthos, and trace these changes to their underlying environmental influences. This requires an observation-based approach that covers coastal and inland aquatic ecosystems in a repeated, synoptic manner. Space-borne sensing systems can provide this capability, supported by coordinated in situ calibration and product validation activities. The design requires high temporal resolution (weekly or better), medium spatial resolution (30 m pixels at nadir to complement Landsat-class sensors), and highly sensitive, ocean-color radiometric quality, high resolution spectroscopy with Visible and Short-Wave IR bands (order of 10 nm or better) to assess both atmospheric correction parameters and land vegetation composition. The strategy needs to include sunglint avoidance schemes, and methods to maximize signal to noise ratios and temporal coverage of aquatic areas. We describe such a system, and urge the U.S. to implement such an observing strategy in the short-term and sustain it for the benefit of humankind.
Impacts of environment on human diseases: a web service for the human exposome
NASA Astrophysics Data System (ADS)
Karssenberg, Derek; Vaartjes, Ilonca; Kamphuis, Carlijn; Strak, Maciek; Schmitz, Oliver; Soenario, Ivan; de Jong, Kor
2017-04-01
The exposome is the totality of human environmental exposures from conception onwards. Identifying the contribution of the exposome to human diseases and health is a key issue in health research. Examples include the effect of air pollution exposure on cardiovascular diseases, the impact of disease vectors (mosquitos) and surface hydrology exposure on malaria, and the effect of fast food restaurant exposure on obesity. Essential to health research is to disentangle the effects of the exposome and genome on health. Ultimately this requires quantifying the totality of all human exposures, for each individual in the studied human population. This poses a massive challenge to geoscientists, as environmental data are required at a high spatial and temporal resolution, with a large spatial and temporal coverage representing the area inhabited by the population studied and the time span representing several decades. Then, these data need to be combined with space-time paths of individuals to calculate personal exposures for each individual in the population. The Global and Geo Health Data Centre is taking this challenge by providing a web service capable of enriching population data with exposome information. Our web service can generate environmental information either from archived national (up to 5 m spatial and 1 h temporal resolution) and global environmental information or generated on the fly using environmental models running as microservices. On top of these environmental data services runs an individual exposure service enabling health researchers to select different spatial and temporal aggregation methods and to upload space-time paths of individuals. These are then enriched with personal exposures and eventually returned to the user. We illustrate the service in an example of individual exposures to air pollutants calculated from hyper resolution air pollution data and various approaches to estimate space-time paths of individuals.
NASA Astrophysics Data System (ADS)
Fernandez, Valerie; Martimort, Philippe; Spoto, Francois; Sy, Omar; Laberinti, Paolo
2013-10-01
GMES is a joint initiative of the European Commission (EC) and the European Space Agency (ESA), designed to establish a European capacity for the provision and use of operational monitoring information for environment and security applications. ESA's role in GMES is to provide the definition and the development of the space- and ground-related system elements. GMES Sentinel-2 mission provides continuity to services relying on multi-spectral highresolution optical observations over global terrestrial surfaces. The key mission objectives for Sentinel-2 are: (1) to provide systematic global acquisitions of high-resolution multi-spectral imagery with a high revisit frequency, (2) to provide enhanced continuity of multi-spectral imagery provided by the SPOT series of satellites, and (3) to provide observations for the next generation of operational products such as landcover maps, land change detection maps, and geophysical variables. Consequently, Sentinel-2 will directly contribute to the Land Monitoring, Emergency Response, and Security services. The corresponding user requirements have driven the design towards a dependable multi-spectral Earthobservation system featuring the MSI with 13 spectral bands spanning from the visible and the near infrared to the short wave infrared. The spatial resolution varies from 10 m to 60 m depending on the spectral band with a 290 km field of view. This unique combination of high spatial resolution, wide field of view and large spectral coverage will represent a major step forward compared to current multi-spectral missions. The mission foresees a series of satellites, each having a 7.25-year lifetime (extendable to 12 years) over a 20-year period starting with the launch of Sentinel-2A foreseen by mid-2014. During full operations two identical satellites will be maintained in the same sun synchronous orbit with a phase delay of 180° providing a revisit time of five days at the equator.
NASA Astrophysics Data System (ADS)
Rieckh, Therese; Anthes, Richard; Randel, William; Ho, Shu-Peng; Foelsche, Ulrich
2017-03-01
We use GPS radio occultation (RO) data to investigate the structure and temporal behavior of extremely dry, high-ozone tropospheric air in the tropical western Pacific during the 6-week period of the CONTRAST (CONvective TRansport of Active Species in the Tropics) experiment (January and February 2014). Our analyses are aimed at testing whether the RO method is capable of detecting these extremely dry layers and evaluating comparisons with in situ measurements, satellite observations, and model analyses. We use multiple data sources as comparisons, including CONTRAST research aircraft profiles, radiosonde profiles, AIRS (Atmospheric Infrared Sounder) satellite retrievals, and profiles extracted from the ERA (ERA-Interim reanalysis) and the GFS (US National Weather Service Global Forecast System) analyses, as well as MTSAT-2 satellite images. The independent and complementary radiosonde, aircraft, and RO data provide high vertical resolution observations of the dry layers. However, they all have limitations. The coverage of the radiosonde data is limited by having only a single station in this oceanic region; the aircraft data are limited in their temporal and spatial coverage; and the RO data are limited in their number and horizontal resolution over this period. However, nearby observations from the three types of data are highly consistent with each other and with the lower-vertical-resolution AIRS profiles. They are also consistent with the ERA and GFS data. We show that the RO data, used here for the first time to study this phenomenon, contribute significant information on the water vapor content and are capable of detecting layers in the tropics and subtropics with extremely low humidity (less than 10 %), independent of the retrieval used to extract moisture information. Our results also verify the quality of the ERA and GFS data sets, giving confidence to the reanalyses and their use in diagnosing the full four-dimensional structure of the dry layers.
NASA Technical Reports Server (NTRS)
2001-01-01
This ASTER image was acquired on July 23, 2001 and covers an area of 64 x 72 km. The data were processed to create a simulated natural color image. From its start as a sleepy Spanish pueblo in 1781, LA and its metropolitan area has grown to become an ethnically diverse, semitropical megalopolis, laying claim as the principal center of the western US and the nation's second largest urban area. The city's economy is based on international trade, aerospace, agriculture, tourism, and filmmaking. LA provides a glimpse of the typically cosmopolitan and global city of the future.The image is located at 34.1 degrees north latitude and 118.2 degrees west longitude. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance.NASA Technical Reports Server (NTRS)
2000-01-01
This ASTER images was acquired on May 2, 2000 over the North Patagonia Ice Sheet, Chile near latitude 47 degrees south, longitude 73 degrees west. The image covers 36 x 30 km. The false color composite displays vegetation in red. The image dramatically shows a single large glacier, covered with crevasses. A semi-circular terminal moraine indicates that the glacier was once more extensive than at present. ASTER data are being acquired over hundreds of glaciers worldwide to measure their changes over time. Since glaciers are sensitive indicators of warming or cooling, this program can provide global data set critical to understand climate change.This image is located at 46.5 degrees south latitude and 73.9 degrees west longitude. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface heat balance.A Robust Multi-Scale Modeling System for the Study of Cloud and Precipitation Processes
NASA Technical Reports Server (NTRS)
Tao, Wei-Kuo
2012-01-01
During the past decade, numerical weather and global non-hydrostatic models have started using more complex microphysical schemes originally developed for high resolution cloud resolving models (CRMs) with 1-2 km or less horizontal resolutions. These microphysical schemes affect the dynamic through the release of latent heat (buoyancy loading and pressure gradient) the radiation through the cloud coverage (vertical distribution of cloud species), and surface processes through rainfall (both amount and intensity). Recently, several major improvements of ice microphysical processes (or schemes) have been developed for cloud-resolving model (Goddard Cumulus Ensemble, GCE, model) and regional scale (Weather Research and Forecast, WRF) model. These improvements include an improved 3-ICE (cloud ice, snow and graupel) scheme (Lang et al. 2010); a 4-ICE (cloud ice, snow, graupel and hail) scheme and a spectral bin microphysics scheme and two different two-moment microphysics schemes. The performance of these schemes has been evaluated by using observational data from TRMM and other major field campaigns. In this talk, we will present the high-resolution (1 km) GeE and WRF model simulations and compared the simulated model results with observation from recent field campaigns [i.e., midlatitude continental spring season (MC3E; 2010), high latitude cold-season (C3VP, 2007; GCPEx, 2012), and tropical oceanic (TWP-ICE, 2006)].
An integrated hyperspectral and SAR satellite constellation for environment monitoring
NASA Astrophysics Data System (ADS)
Wang, Jinnian; Ren, Fuhu; Xie, Chou; An, Jun; Tong, Zhanbo
2017-09-01
A fully-integrated, Hyperspectral optical and SAR (Synthetic Aperture Radar) constellation of small earth observation satellites will be deployed over multiple launches from last December to next five years. The Constellation is expected to comprise a minimum of 16 satellites (8 SAR and 8 optical ) flying in two orbital planes, with each plane consisting of four satellite pairs, equally-spaced around the orbit plane. Each pair of satellites will consist of a hyperspectral/mutispectral optical satellite and a high-resolution SAR satellite (X-band) flying in tandem. The constellation is expected to offer a number of innovative capabilities for environment monitoring. As a pre-launch experiment, two hyperspectral earth observation minisatellites, Spark 01 and 02 were launched as secondary payloads together with Tansat in December 2016 on a CZ-2D rocket. The satellites feature a wide-range hyperspectral imager. The ground resolution is 50 m, covering spectral range from visible to near infrared (420 nm - 1000 nm) and a swath width of 100km. The imager has an average spectral resolution of 5 nm with 148 channels, and a single satellite could obtain hyperspectral imagery with 2.5 million km2 per day, for global coverage every 16 days. This paper describes the potential applications of constellation image in environment monitoring.
NASA Astrophysics Data System (ADS)
Döll, Petra; Fritsche, Mathias; Eicker, Annette; Müller Schmied, Hannes
2014-11-01
Better quantification of continental water storage variations is expected to improve our understanding of water flows, including evapotranspiration, runoff and river discharge as well as human water abstractions. For the first time, total water storage (TWS) on the land area of the globe as computed by the global water model WaterGAP (Water Global Assessment and Prognosis) was compared to both gravity recovery and climate experiment (GRACE) and global positioning system (GPS) observations. The GRACE satellites sense the effect of TWS on the dynamic gravity field of the Earth. GPS reference points are displaced due to crustal deformation caused by time-varying TWS. Unfortunately, the worldwide coverage of the GPS tracking network is irregular, while GRACE provides global coverage albeit with low spatial resolution. Detrended TWS time series were analyzed by determining scaling factors for mean annual amplitude ( f GRACE) and time series of monthly TWS ( f GPS). Both GRACE and GPS indicate that WaterGAP underestimates seasonal variations of TWS on most of the land area of the globe. In addition, seasonal maximum TWS occurs 1 month earlier according to WaterGAP than according to GRACE on most land areas. While WaterGAP TWS is sensitive to the applied climate input data, none of the two data sets result in a clearly better fit to the observations. Due to the low number of GPS sites, GPS observations are less useful for validating global hydrological models than GRACE observations, but they serve to support the validity of GRACE TWS as observational target for hydrological modeling. For unknown reasons, WaterGAP appears to fit better to GPS than to GRACE. Both GPS and GRACE data, however, are rather uncertain due to a number of reasons, in particular in dry regions. It is not possible to benefit from either GPS or GRACE observations to monitor and quantify human water abstractions if only detrended (seasonal) TWS variations are considered. Regarding GRACE, this is mainly caused by the attenuation of the TWS differences between water abstraction variants due to the filtering required for GRACE TWS. Regarding GPS, station density is too low. Only if water abstractions lead to long-term changes in TWS by depletion or restoration of water storage in groundwater or large surface water bodies, GRACE may be used to support the quantification of human water abstractions.
NASA Astrophysics Data System (ADS)
Ma, X.; Mahecha, M. D.; Migliavacca, M.; Luo, Y.; Urban, M.; Bohn, F. J.; Huth, A.; Reichstein, M.
2017-12-01
A key challenge for monitoring biodiversity change is the lack of consistent measures of biodiversity across space and time. This challenge may be addressed by exploring the potentials provided by novel remote sensing observations. By continuously observing broad-scale patterns of vegetation and land surface parameters, remote sensing can complement the restricted coverage afforded by field measurements. Here we develop methods to infer spatial patterns of biodiversity at ecosystem level from ESA's next-generation Sentinel sensors (Sentinel-1: C-band radar & Sentinel-2: multispectral). Both satellites offer very high spatial (10 m) and temporal resolutions (5 days) measurements with global coverage. We propose and test several ecosystem biodiversity proxies, including landscape spectral diversity, phenological diversity, and canopy structural diversity. These diversity proxies are highly related to some key aspects of essential biodiversity variables (EBVs) as defined by GEO-BON, such as habitat structure, community composition, ecosystem function and structure. We verify spaceborne retrievals of these biodiversity proxies with in situ measurements from drone (spectral diversity), phenocam (phenological diversity), and airborne LiDAR (canopy structural diversity) over multiple flux tower sites within the Mediterranean region. We further compare our remote sensing retrievals of biodiversity proxies against several biodiversity indices as derived from field measurements (incl. ⍺-/β- diversity and Shannon-index) to explore the limitations and potentials of extending the RS proxies to a greater spatial extent. We expect the new concept as to maximize the potential of remote sensing information might help to monitor key aspects of EBVs on a global scale.
WindCam and MSPI: two cloud and aerosol instrument concepts derived from Terra/MISR heritage
NASA Astrophysics Data System (ADS)
Diner, David J.; Mischna, Michael; Chipman, Russell A.; Davis, Ab; Cairns, Brian; Davies, Roger; Kahn, Ralph A.; Muller, Jan-Peter; Torres, Omar
2008-08-01
The Multi-angle Imaging SpectroRadiometer (MISR) has been acquiring global cloud and aerosol data from polar orbit since February 2000. MISR acquires moderately high-resolution imagery at nine view angles from nadir to 70.5°, in four visible/near-infrared spectral bands. Stereoscopic parallax, time lapse among the nine views, and the variation of radiance with angle and wavelength enable retrieval of geometric cloud and aerosol plume heights, height-resolved cloud-tracked winds, and aerosol optical depth and particle property information. Two instrument concepts based upon MISR heritage are in development. The Cloud Motion Vector Camera, or WindCam, is a simplified version comprised of a lightweight, compact, wide-angle camera to acquire multiangle stereo imagery at a single visible wavelength. A constellation of three WindCam instruments in polar Earth orbit would obtain height-resolved cloud-motion winds with daily global coverage, making it a low-cost complement to a spaceborne lidar wind measurement system. The Multiangle SpectroPolarimetric Imager (MSPI) is aimed at aerosol and cloud microphysical properties, and is a candidate for the National Research Council Decadal Survey's Aerosol-Cloud-Ecosystem (ACE) mission. MSPI combines the capabilities of MISR with those of other aerosol sensors, extending the spectral coverage to the ultraviolet and shortwave infrared and incorporating high-accuracy polarimetric imaging. Based on requirements for the nonimaging Aerosol Polarimeter Sensor on NASA's Glory mission, a degree of linear polarization uncertainty of 0.5% is specified within a subset of the MSPI bands. We are developing a polarization imaging approach using photoelastic modulators (PEMs) to accomplish this objective.
NASA Astrophysics Data System (ADS)
Evgenievna Terentieva, Irina; Vladimirovich Glagolev, Mikhail; Dmitrievna Lapshina, Elena; Faritovich Sabrekov, Alexandr; Maksyutov, Shamil
2016-08-01
High-latitude wetlands are important for understanding climate change risks because these environments sink carbon dioxide and emit methane. However, fine-scale heterogeneity of wetland landscapes poses a serious challenge when generating regional-scale estimates of greenhouse gas fluxes from point observations. In order to reduce uncertainties at the regional scale, we mapped wetlands and water bodies in the taiga zone of The West Siberia Lowland (WSL) on a scene-by-scene basis using a supervised classification of Landsat imagery. Training data consist of high-resolution images and extensive field data collected at 28 test areas. The classification scheme aims at supporting methane inventory applications and includes seven wetland ecosystem types comprising nine wetland complexes distinguishable at the Landsat resolution. To merge typologies, mean relative areas of wetland ecosystems within each wetland complex type were estimated using high-resolution images. Accuracy assessment based on 1082 validation polygons of 10 × 10 pixel size indicated an overall map accuracy of 79 %. The total area of the WSL wetlands and water bodies was estimated to be 52.4 Mha or 4-12 % of the global wetland area. Ridge-hollow complexes prevail in WSL's taiga zone accounting for 33 % of the total wetland area, followed by pine bogs or "ryams" (23 %), ridge-hollow-lake complexes (16 %), open fens (8 %), palsa complexes (7 %), open bogs (5 %), patterned fens (4 %), and swamps (4 %). Various oligotrophic environments are dominant among wetland ecosystems, while poor fens cover only 14 % of the area. Because of the significant change in the wetland ecosystem coverage in comparison to previous studies, a considerable reevaluation of the total CH4 emissions from the entire region is expected. A new Landsat-based map of WSL's taiga wetlands provides a benchmark for validation of coarse-resolution global land cover products and wetland data sets in high latitudes.
PolarCube: A High Resolution Passive Microwave Satellite for Sounding and Imaging at 118 GHz
NASA Astrophysics Data System (ADS)
Weaver, R. L.; Gallaher, D. W.; Gasiewski, A. J.; Sanders, B.; Periasamy, L.; Hwang, K.; Alvarenga, G.; Hickey, A. M.
2013-12-01
PolarCube is a 3U CubeSat hosting an eight-channel passive microwave spectrometer operating at the 118.7503 GHz oxygen resonance that is currently in development. The project has an anticipated launch date in early 2015. It is currently being designed to operate for approximately12 months on orbit to provide the first global 118-GHz spectral imagery of the Earth over full seasonal cycle and to sound Arctic vertical temperature structure. The principles used by PolarCube for temperature sounding are well established in number of peer-reviewed papers going back more than two decades, although the potential for sounding from a CubeSat has never before been demonstrated in space. The PolarCube channels are selected to probe atmospheric emission over a range of vertical levels from the surface to lower stratosphere. This capability has been available operationally for over three decades, but at lower frequencies and higher altitudes that do not provide the spatial resolution that will be achieved by PolarCube. While the NASA JPSS ATMS satellite sensor provides global coverage at ~32 km resolution, the PolarCube will improve on this resolution by a factor of two, thus facilitating the primary science goal of determining sea ice concentration and extent while at the same time collecting profile data on atmospheric temperature. Additionally, we seek to correlate freeze-thaw line data from SMAP with our near simultaneously collected atmospheric temperature data. In addition to polar science, PolarCube will provide a first demonstration of a very low cost passive microwave sounder that if operated in a fleet configuration would have the potential to fulfill the goals of the Precipitation Atmospheric Temperature and Humidity (PATH) mission, as defined in the NRC Decadal Survey. PolarCube 118-GHz passive microwave spectrometer in deployed configuration
NASA Astrophysics Data System (ADS)
Hardman, M.; Brodzik, M. J.; Long, D. G.; Paget, A. C.; Armstrong, R. L.
2015-12-01
Beginning in 1978, the satellite passive microwave data record has been a mainstay of remote sensing of the cryosphere, providing twice-daily, near-global spatial coverage for monitoring changes in hydrologic and cryospheric parameters that include precipitation, soil moisture, surface water, vegetation, snow water equivalent, sea ice concentration and sea ice motion. Currently available global gridded passive microwave data sets serve a diverse community of hundreds of data users, but do not meet many requirements of modern Earth System Data Records (ESDRs) or Climate Data Records (CDRs), most notably in the areas of intersensor calibration, quality-control, provenance and consistent processing methods. The original gridding techniques were relatively primitive and were produced on 25 km grids using the original EASE-Grid definition that is not easily accommodated in modern software packages. Further, since the first Level 3 data sets were produced, the Level 2 passive microwave data on which they were based have been reprocessed as Fundamental CDRs (FCDRs) with improved calibration and documentation. We are funded by NASA MEaSUREs to reprocess the historical gridded data sets as EASE-Grid 2.0 ESDRs, using the most mature available Level 2 satellite passive microwave (SMMR, SSM/I-SSMIS, AMSR-E) records from 1978 to the present. We have produced prototype data from SSM/I and AMSR-E for the year 2003, for review and feedback from our Early Adopter user community. The prototype data set includes conventional, low-resolution ("drop-in-the-bucket" 25 km) grids and enhanced-resolution grids derived from the two candidate image reconstruction techniques we are evaluating: 1) Backus-Gilbert (BG) interpolation and 2) a radiometer version of Scatterometer Image Reconstruction (SIR). We summarize our temporal subsetting technique, algorithm tuning parameters and computational costs, and include sample SSM/I images at enhanced resolutions of up to 3 km. We are actively working with our Early Adopters to finalize content and format of this new, consistently-processed high-quality satellite passive microwave ESDR.
An Interdisciplinary Approach at Studying the Earth-Sun System with GPS/GNSS and GPS-like Signals
NASA Technical Reports Server (NTRS)
Zuffada, Cinzia; Hajj, George; Mannucci, Anthony J.; Chao, Yi; Ao, Chi; Zumberge, James
2005-01-01
The value of Global Positioning Satellites (GPS) measurements to atmospheric science, space physics, and ocean science, is now emerging or showing a potential to play a major role in the evolving programs of NASA, NSF and NOAA. The objective of this communication is to identify and articulate the key scientific questions that are optimally, or perhaps uniquely, addressed by GPS or GPS-like observations, and discuss their relevance to existing or planned national Earth-science research programs. The GPS-based ocean reflection experiments performed to date have demonstrated the precision and spatial resolution suitable to altimetric applications that require higher spatial resolution and more frequent repeat than the current radar altimeter satellites. GPS radio occultation is promising as a climate monitoring tool because of its benchmark properties: its raw observable is based on extremely accurate timing measurements. GPS-derived temperature profiles can provide meaningful climate trend information over decadal time scales without the need for overlapping missions or mission-to-mission calibrations. By acquiring data as GPS satellites occult behind the Earth's limb, GPS also provides high vertical resolution information on the vertical structure of electron density with global coverage. New experimental techniques will create more comprehensive TEC maps by using signals reflected from the oceans and received in orbit. This communication will discuss a potential future GNSS Earth Observing System project which would deploy a constellation of satellites using GPS and GPS-like measurements, to obtain a) topography measurements based on GPS reflections with an accuracy and horizontal resolution suitable for eddy monitoring, and h) climate-records quality atmospheric temperature profiles. The constellation would also provide for measurements of ionospheric elec tron density. This is a good example of an interdisciplinary mission concept, with broad science objectives of high societal relevance, al l resting on common cost-effective technology.
Reliability of Navigation Service Provided by the Global Positioning System
DOT National Transportation Integrated Search
1985-09-01
The planned NAVSTAR/GPS satellite constellation of 18 satellites plus 3 active will provide excellent coverage over the continental United States (CONUS) if all are operating properly. This report examines the coverage under conditions of one satelli...
Making sense of global warming: Norwegians appropriating knowledge of anthropogenic climate change.
Ryghaug, Marianne; Sørensen, Knut Holtan; Naess, Robert
2011-11-01
This paper studies how people reason about and make sense of human-made global warming, based on ten focus group interviews with Norwegian citizens. It shows that the domestication of climate science knowledge was shaped through five sense-making devices: news media coverage of changes in nature, particularly the weather, the coverage of presumed experts' disagreement about global warming, critical attitudes towards media, observations of political inaction, and considerations with respect to everyday life. These sense-making devices allowed for ambiguous outcomes, and the paper argues four main outcomes with respect to the domestication processes: the acceptors, the tempered acceptors, the uncertain and the sceptics.
NASA Astrophysics Data System (ADS)
Peiro, Hélène; Emili, Emanuele; Cariolle, Daniel; Barret, Brice; Le Flochmoën, Eric
2018-05-01
The Infrared Atmospheric Sounder Instrument (IASI) allows global coverage with very high spatial resolution and its measurements are promising for long-term ozone monitoring. In this study, Microwave Limb Sounder (MLS) O3 profiles and IASI O3 partial columns (1013.25-345 hPa) are assimilated in a chemistry transport model to produce 6-hourly analyses of tropospheric ozone for 6 years (2008-2013). We have compared and evaluated the IASI-MLS analysis and the MLS analysis to assess the added value of IASI measurements. The global chemical transport model MOCAGE (MOdèle de Chimie Atmosphérique à Grande Echelle) has been used with a linear ozone chemistry scheme and meteorological forcing fields from ERA-Interim (ECMWF global reanalysis) with a horizontal resolution of 2° × 2° and 60 vertical levels. The MLS and IASI O3 retrievals have been assimilated with a 4-D variational algorithm to constrain stratospheric and tropospheric ozone respectively. The ozone analyses are validated against ozone soundings and tropospheric column ozone (TCO) from the OMI-MLS residual method. In addition, an Ozone ENSO Index (OEI) is computed from the analysis to validate the TCO variability during the ENSO events. We show that the assimilation of IASI reproduces the variability of tropospheric ozone well during the period under study. The variability deduced from the IASI-MLS analysis and the OMI-MLS measurements are similar for the period of study. The IASI-MLS analysis can reproduce the extreme oscillation of tropospheric ozone caused by ENSO events over the tropical Pacific Ocean, although a correction is required to reduce a constant bias present in the IASI-MLS analysis.
NASA Technical Reports Server (NTRS)
King, Michael D.; Platnick, Steven; Chu, D. Allen; Moody, Eric G.
2001-01-01
MODIS is an earth-viewing cross-track scanning spectroradiometer launched on the Terra satellite in December 1999. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, sun-synchronous platform at an altitude of 705 km, and provides images in 36 spectral bands between 0.415 and 14.235 microns with spatial resolutions of 250 m (two bands), 500 m (five bands) and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean, and atmospheric processes. In this presentation we review the comprehensive set of remote sensing algorithms that have been developed for the remote sensing of atmospheric properties using MODIS data, placing primary emphasis on the principal atmospheric applications of (i) developing a cloud mask for distinguishing clear sky from clouds, (ii) retrieving global cloud radiative and microphysical properties, including cloud top pressure and temperature, effective emissivity, cloud optical thickness, thermodynamic phase, and effective radius, (iii) monitoring tropospheric aerosol optical thickness over the land and ocean and aerosol size distribution over the ocean, (iv) determining atmospheric profiles of moisture and temperature, and (v) estimating column water amount. The physical principles behind the determination of each of these atmospheric products will be described, together with an example of their application using MODIS observations to the east Asian region in Spring 2001. All products are archived into two categories: pixel-level retrievals (referred to as Level-2 products) and global gridded products at a latitude and longitude resolution of 1 degree (Level-3 products). An overview of the MODIS atmosphere algorithms and products, status, validation activities, and early level-2 and -3 results will be presented.
Remote Sensing of Cloud, Aerosol, and Water Vapor Properties from MODIS
NASA Technical Reports Server (NTRS)
King, Michael D.; Platnick, Steven; Menzel, W. Paul; Kaufman, Yoram J.; Ackerman, Steven A.; Tanre, Didier; Gao, Bo-Cai
2001-01-01
MODIS is an earth-viewing cross-track scanning spectroradiometer launched on the Terra satellite in December 1999. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from a polar orbiting, sun-synchronous, platform at an altitude of 705 kilometers, and provides images in 36 spectral bands between 0.415 and 14.235 micrometers with spatial resolutions of 250 meters (2 bands), 500 meters (5 bands) and 1000 meters (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean, and atmospheric processes. In this presentation we review the comprehensive set of remote sensing algorithms that have been developed for the remote sensing of atmospheric properties using MODIS data, placing primary emphasis on the principal atmospheric applications of (i) developing a cloud mask for distinguishing clear sky from clouds, (ii) retrieving global cloud radiative and microphysical properties, including cloud top pressure and temperature, effective emissivity, cloud optical thickness, thermodynamic phase, and effective radius, (iii) monitoring tropospheric aerosol optical thickness over the land and ocean and aerosol size distribution over the ocean, (iv) determining atmospheric profiles of moisture and temperature, and (v) estimating column water amount. The physical principles behind the determination of each of these atmospheric products will be described, together with an example of their application using MODIS observations. All products are archived into two categories: pixel-level retrievals (referred to as Level-2 products) and global gridded products at a latitude and longitude resolution of 1 degree (Level-3 products). An overview of the MODIS atmosphere algorithms and products, status, validation activities, and early level-2 and -3 results will be presented.
Terahertz and far-infrared synchrotron spectroscopy and global modeling of methyl mercaptan, CH332SH
NASA Astrophysics Data System (ADS)
Xu, Li-Hong; Lees, R. M.; Crabbe, G. T.; Myshrall, J. A.; Müller, H. S. P.; Endres, C. P.; Baum, O.; Lewen, F.; Schlemmer, S.; Menten, K. M.; Billinghurst, B. E.
2012-09-01
In this work, terahertz and Fourier transform far-infrared (FTFIR) synchrotron spectra of methyl mercaptan, CH3SH, have been investigated in order to provide new laboratory information for enhanced observations of this species in interstellar molecular clouds and star-forming regions. Like its methanol cousin, methyl mercaptan has particularly rich spectra associated with its large-amplitude internal rotation that extend throughout the THz and FIR regions. We have recorded new spectra for CH3SH from 1.1-1.5 and 1.790-1.808 THz at the University of Cologne as well as high-resolution FTFIR synchrotron spectra from 50-550 cm-1 at 0.001 cm-1 resolution on the far-IR beam-line at the Canadian Light Source. Assignments are reported for rotational quantum numbers up to J ≈ 40 and K ≈ 15, and torsional states up to vt = 2 for the THz measurements and vt = 3 for the FTFIR observations. The THz and FTFIR measurements together with literature results have been combined in a global analysis of a dataset comprising a total of 1725 microwave and THz frequencies together with ˜18000 FTFIR transitions, ranging up to vt = 2 and Jmax = 30 for MW/THz and 40 for FTFIR. The global fit employs 78 torsion-rotation parameters and has achieved a weighted standard deviation of ˜1.1. A prediction list (vt ≤ 2, J ≤ 45 and K ≤ 20) has been generated from the model giving essentially complete coverage of observable CH332SH transitions within the bandwidths of major new astronomical facilities such as HIFI (Heterodyne Instrument for the Far Infrared) on the Herschel Space Observatory, ALMA (Atacama Large Millimeter Array), SOFIA (Stratospheric Observatory For Infrared Astronomy) and APEX (Atacama Pathfinder Experiment) to close to spectroscopic accuracy.
Global Dynamic Exposure and the OpenBuildingMap
NASA Astrophysics Data System (ADS)
Schorlemmer, D.; Beutin, T.; Hirata, N.; Hao, K. X.; Wyss, M.; Cotton, F.; Prehn, K.
2015-12-01
Detailed understanding of local risk factors regarding natural catastrophes requires in-depth characterization of the local exposure. Current exposure capture techniques have to find the balance between resolution and coverage. We aim at bridging this gap by employing a crowd-sourced approach to exposure capturing focusing on risk related to earthquake hazard. OpenStreetMap (OSM), the rich and constantly growing geographical database, is an ideal foundation for us. More than 2.5 billion geographical nodes, more than 150 million building footprints (growing by ~100'000 per day), and a plethora of information about school, hospital, and other critical facility locations allow us to exploit this dataset for risk-related computations. We will harvest this dataset by collecting exposure and vulnerability indicators from explicitly provided data (e.g. hospital locations), implicitly provided data (e.g. building shapes and positions), and semantically derived data, i.e. interpretation applying expert knowledge. With this approach, we can increase the resolution of existing exposure models from fragility classes distribution via block-by-block specifications to building-by-building vulnerability. To increase coverage, we will provide a framework for collecting building data by any person or community. We will implement a double crowd-sourced approach to bring together the interest and enthusiasm of communities with the knowledge of earthquake and engineering experts. The first crowd-sourced approach aims at collecting building properties in a community by local people and activists. This will be supported by tailored building capture tools for mobile devices for simple and fast building property capturing. The second crowd-sourced approach involves local experts in estimating building vulnerability that will provide building classification rules that translate building properties into vulnerability and exposure indicators as defined in the Building Taxonomy 2.0 developed by the Global Earthquake Model (GEM). These indicators will then be combined with a hazard model using the GEM OpenQuake engine to compute a risk model. The free/open framework we will provide can be used on commodity hardware for local to regional exposure capturing and for communities to understand their earthquake risk.
NASA Astrophysics Data System (ADS)
Burrage, D. M.; Wesson, J. C.; Hwang, P. A.; Wang, D. W.; Wijesekera, H. W.
2016-02-01
Airborne mapping of Sea Surface Salinity (SSS) with L-band radiometers has been practiced for 20 yrs., while global satellite observations began with the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) Satellite launch in 2009. Airborne data with high ( 1km) resolution, but limited coverage, complement the lower resolution ( 35 km at nadir) but global coverage and 3-5 day revisit of SMOS. The record June, 2011 Mississippi R. peak flood, with flows exceeding 42,500 m^3/s, required diversions into Lake Pontchartrain and the Atchafalaya R. to avoid flooding New Orleans and Baton Rouge. The resulting merged outflows formed a single freshwater plume that spanned the Mississippi, Louisiana and Texas `Gulf Coast', and reached up to 300 km across the shelf. SSS was mapped by the NRL airborne Salinity Temperature and Roughness Remote Scanner (STARRS) and SMOS radiometers during a two week (2-13 June 2011) campaign immediately following the flood crest. STARRS obtained oblique across-shelf transects spanning the Northern Gulf of Mexico, under-flying SMOS, and shorter zig-zag coastal transects. SSS samples from a ship near the shelf edge agreed well with STARRS and SMOS after applying standard geophysical correction models and roughness corrections from an SSA/SPM E-M model and an advanced wave spectrum. The minimum SMOS footprint size (35 km at nadir), produced a coastal data gap filled by STARRS transects that reached the coast. The 200 km overlap between the two sensors along coincident ground tracks agreed closely near the frontal boundary, with salinity contrasts of 7-15 psu over a 10 km span at the plume edge evident in both data sets. Successive SMOS Level 2 (L2) SSS data swaths obtained at 2-5 day intervals showed the evolution of the plume in three well-separated seaward extensions located near the Mississippi Delta, and well east and west of the Delta. The dispersal of the plume was also detected by SMOS following the airborne campaign.
Improved Thin Cirrus and Terminator Cloud Detection in CERES Cloud Mask
NASA Technical Reports Server (NTRS)
Trepte, Qing; Minnis, Patrick; Palikonda, Rabindra; Spangenberg, Doug; Haeffelin, Martial
2006-01-01
Thin cirrus clouds account for about 20-30% of the total cloud coverage and affect the global radiation budget by increasing the Earth's albedo and reducing infrared emissions. Thin cirrus, however, are often underestimated by traditional satellite cloud detection algorithms. This difficulty is caused by the lack of spectral contrast between optically thin cirrus and the surface in techniques that use visible (0.65 micron ) and infrared (11 micron ) channels. In the Clouds and the Earth s Radiant Energy System (CERES) Aqua Edition 1 (AEd1) and Terra Edition 3 (TEd3) Cloud Masks, thin cirrus detection is significantly improved over both land and ocean using a technique that combines MODIS high-resolution measurements from the 1.38 and 11 micron channels and brightness temperature differences (BTDs) of 11-12, 8.5-11, and 3.7-11 micron channels. To account for humidity and view angle dependencies, empirical relationships were derived with observations from the 1.38 micron reflectance and the 11-12 and 8.5-11 micron BTDs using 70 granules of MODIS data in 2002 and 2003. Another challenge in global cloud detection algorithms occurs near the day/night terminator where information from the visible 0.65 micron channel and the estimated solar component of 3.7 micron channel becomes less reliable. As a result, clouds are often underestimated or misidentified near the terminator over land and ocean. Comparisons between the CLAVR-x (Clouds from Advanced Very High Resolution Radiometer [AVHRR]) cloud coverage and Geoscience Laser Altimeter System (GLAS) measurements north of 60 N indicate significant amounts of missing clouds from CLAVR-x because this part of the world was near the day/night terminator viewed by AVHRR. Comparisons between MODIS cloud products (MOD06) and GLAS in the same region also show similar difficulties with MODIS cloud retrievals. The consistent detection of clouds through out the day is needed to provide reliable cloud and radiation products for CERES and other research efforts involving the modeling of clouds and their interaction with the radiation budget.
NASA Astrophysics Data System (ADS)
Kilian, L.; Stahl, U.; Kossev, I.; Sokolowski, M.; Fink, R.; Umbach, E.
2008-07-01
The structural order of 1,4,9,10-naphthalene-tetracarboxylicacid-dianhydride (NTCDA) monolayers on Ag(1 1 1) has been investigated by spot profile analysis low energy electron diffraction (SPA-LEED). For increasing coverage, we find a sequence of three highly ordered structures: a commensurate structure (α), a uniaxially incommensurate structure (α 2), and an incommensurate structure (β) with coverages of 0.9 ML, 0.95 ML, and 1 (saturated) monolayer (ML), respectively. In the high coverage regime, the structures coexist and a coverage increase causes a change of their relative fractions. The α and β structures were known before [U. Stahl, D. Gador, A. Soukopp, R. Fink, E. Umbach, Surf. Sci. 414 (1998) 423], but the β structure was proposed as commensurate, since its very small misfit with respect to a commensurate structure could not be resolved. This misfit leads to a periodic modulation, causing additional Moiré satellites in the diffraction pattern. This finding demonstrates the importance of high resolution methods for the geometry determination of large organic adsorbates.
NASA Astrophysics Data System (ADS)
Bolten, J.; Crow, W.; Zhan, X.; Reynolds, C.
2008-08-01
Timely and accurate monitoring of global weather anomalies and drought conditions is essential for assessing global crop conditions. Soil moisture observations are particularly important for crop yield fluctuations provided by the US Department of Agriculture (USDA) Production Estimation and Crop Assessment Division (PECAD). The current system utilized by PECAD estimates soil moisture from a 2-layer water balance model based on precipitation and temperature data from World Meteorological Organization (WMO) and US Air Force Weather Agency (AFWA). The accuracy of this system is highly dependent on the data sources used; particularly the accuracy, consistency, and spatial and temporal coverage of the land and climatic data input into the models. However, many regions of the globe lack observations at the temporal and spatial resolutions required by PECAD. This study incorporates NASA's soil moisture remote sensing product provided by the EOS Advanced Microwave Scanning Radiometer (AMSR-E) into the U.S. Department of Agriculture Crop Assessment and Data Retrieval (CADRE) decision support system. A quasi-global-scale operational data assimilation system has been designed and implemented to provide CADRE a daily product of integrated AMSR-E soil moisture observations with the PECAD two-layer soil moisture model forecasts. A methodology of the system design and a brief evaluation of the system performance over the Conterminous United States (CONUS) is presented.
Li, Tie-Mei; Zhang, Ju-en; Lin, Rui; Chen, She; Luo, Minmin; Dong, Meng-Qiu
2016-01-01
Sleep is a ubiquitous, tightly regulated, and evolutionarily conserved behavior observed in almost all animals. Prolonged sleep deprivation can be fatal, indicating that sleep is a physiological necessity. However, little is known about its core function. To gain insight into this mystery, we used advanced quantitative proteomics technology to survey the global changes in brain protein abundance. Aiming to gain a comprehensive profile, our proteomics workflow included filter-aided sample preparation (FASP), which increased the coverage of membrane proteins; tandem mass tag (TMT) labeling, for relative quantitation; and high resolution, high mass accuracy, high throughput mass spectrometry (MS). In total, we obtained the relative abundance ratios of 9888 proteins encoded by 6070 genes. Interestingly, we observed significant enrichment for mitochondrial proteins among the differentially expressed proteins. This finding suggests that sleep deprivation strongly affects signaling pathways that govern either energy metabolism or responses to mitochondrial stress. Additionally, the differentially-expressed proteins are enriched in pathways implicated in age-dependent neurodegenerative diseases, including Parkinson’s, Huntington’s, and Alzheimer’s, hinting at possible connections between sleep loss, mitochondrial stress, and neurodegeneration. PMID:27684481
Feasibility Study For A Spaceborne Ozone/Aerosol Lidar System
NASA Technical Reports Server (NTRS)
Campbell, Richard E.; Browell, Edward V.; Ismail, Syed; Dudelzak, Alexander E.; Carswell, Allan I.; Ulitsky, Arkady
1997-01-01
Because ozone provides a shield against harmful ultraviolet radiation, determines the temperature profile in the stratosphere, plays important roles in tropospheric chemistry and climate, and is a health risk near the surface, changes in natural ozone layers at different altitudes and their global impact are being intensively researched. Global ozone coverage is currently provided by passive optical and microwave satellite sensors that cannot deliver high spatial resolution measurements and have particular limitations in the troposphere. Vertical profiling DIfferential Absorption Lidars (DIAL) have shown excellent range-resolved capabilities, but these systems have been large, inefficient, and have required continuous technical attention for long term operations. Recently, successful, autonomous DIAL measurements have been performed from a high-altitude aircraft (LASE - Lidar Atmospheric Sensing Experiment), and a space-qualified aerosol lidar system (LITE - Laser In-space Technology Experiment) has performed well on Shuttle. Based on the above successes, NASA and the Canadian Space Agency are jointly studying the feasibility of developing ORACLE (Ozone Research with Advanced Cooperative Lidar Experiments), an autonomously operated, compact DIAL instrument to be placed in orbit using a Pegasus class launch vehicle.
NASA Technical Reports Server (NTRS)
Meister, Gerhard; Franz, Bryan A.
2011-01-01
The Moderate-Resolution Imaging Spectroradiometer (MODIS) on NASA s Earth Observing System (EOS) satellite Terra provides global coverage of top-of-atmosphere (TOA) radiances that have been successfully used for terrestrial and atmospheric research. The MODIS Terra ocean color products, however, have been compromised by an inadequate radiometric calibration at the short wavelengths. The Ocean Biology Processing Group (OBPG) at NASA has derived radiometric corrections using ocean color products from the SeaWiFS sensor as truth fields. In the R2010.0 reprocessing, these corrections have been applied to the whole mission life span of 10 years. This paper presents the corrections to the radiometric gains and to the instrument polarization sensitivity, demonstrates the improvement to the Terra ocean color products, and discusses issues that need further investigation. Although the global averages of MODIS Terra ocean color products are now in excellent agreement with those of SeaWiFS and MODIS Aqua, and image quality has been significantly improved, the large corrections applied to the radiometric calibration and polarization sensitivity require additional caution when using the data.
Mapping the global land surface using 1 km AVHRR data
Lauer, D.T.; Eidenshink, J.C.
1998-01-01
The scientific requirements for mapping the global land surface using 1 km advanced very high resolution radiometer (AVHRR) data have been set forth by the U.S. Global Change Research Program; the International Geosphere Biosphere Programme (IGBP); The United Nations; the National Oceanic and Atmospheric Administration (NOAA); the Committee on Earth Observations Satellites; and the National Aeronautics and Space Administration (NASA) mission to planet Earth (MTPE) program. Mapping the global land surface using 1 km AVHRR data is an international effort to acquire, archive, process, and distribute 1 km AVHRR data to meet the needs of the international science community. A network of AVHRR receiving stations, along with data recorded by NOAA, has been acquiring daily global land coverage since April 1, 1992. A data set of over 70,000 AVHRR images is archived and distributed by the United States Geological Survey (USGS) EROS Data Center, and the European Space Agency. Under the guidance of the IGBP, processing standards have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NDVI) composites. The major uses of the composites are for the study of surface vegetation condition, mapping land cover, and deriving biophysical characteristics of terrestrial ecosystems. A time-series of 54 10-day global vegetation index composites for the period of April 1, 1992 through September 1993 has been produced. The production of a time-series of 33 10-day global vegetation index composites using NOAA-14 data for the period of February 1, 1995 through December 31, 1995 is underway. The data products are available from the USGS, in cooperation with NASA's MTPE program and other international organizations.
High-Resolution Spatial Distribution and Estimation of Access to Improved Sanitation in Kenya.
Jia, Peng; Anderson, John D; Leitner, Michael; Rheingans, Richard
2016-01-01
Access to sanitation facilities is imperative in reducing the risk of multiple adverse health outcomes. A distinct disparity in sanitation exists among different wealth levels in many low-income countries, which may hinder the progress across each of the Millennium Development Goals. The surveyed households in 397 clusters from 2008-2009 Kenya Demographic and Health Surveys were divided into five wealth quintiles based on their national asset scores. A series of spatial analysis methods including excess risk, local spatial autocorrelation, and spatial interpolation were applied to observe disparities in coverage of improved sanitation among different wealth categories. The total number of the population with improved sanitation was estimated by interpolating, time-adjusting, and multiplying the surveyed coverage rates by high-resolution population grids. A comparison was then made with the annual estimates from United Nations Population Division and World Health Organization /United Nations Children's Fund Joint Monitoring Program for Water Supply and Sanitation. The Empirical Bayesian Kriging interpolation produced minimal root mean squared error for all clusters and five quintiles while predicting the raw and spatial coverage rates of improved sanitation. The coverage in southern regions was generally higher than in the north and east, and the coverage in the south decreased from Nairobi in all directions, while Nyanza and North Eastern Province had relatively poor coverage. The general clustering trend of high and low sanitation improvement among surveyed clusters was confirmed after spatial smoothing. There exists an apparent disparity in sanitation among different wealth categories across Kenya and spatially smoothed coverage rates resulted in a closer estimation of the available statistics than raw coverage rates. Future intervention activities need to be tailored for both different wealth categories and nationally where there are areas of greater needs when resources are limited.
State of equity: childhood immunization in the World Health Organization African Region
Casey, Rebecca Mary; Hampton, Lee McCalla; Anya, Blanche-philomene Melanga; Gacic-Dobo, Marta; Diallo, Mamadou Saliou; Wallace, Aaron Stuart
2017-01-01
Introduction In 2010, the Global Vaccine Action Plan called on all countries to reach and sustain 90% national coverage and 80% coverage in all districts for the third dose of diphtheria-tetanus-pertussis vaccine (DTP3) by 2015 and for all vaccines in national immunization schedules by 2020. The aims of this study are to analyze recent trends in national vaccination coverage in the World Health Organization African Region andto assess how these trends differ by country income category. Methods We compared national vaccination coverage estimates for DTP3 and the first dose of measles-containing vaccine (MCV) obtained from the World Health Organization (WHO)/United Nations Children’s Fund (UNICEF) joint estimates of national immunization coverage for all African Region countries. Using United Nations (UN) population estimates of surviving infants and country income category for the corresponding year, we calculated population-weighted average vaccination coverage by country income category (i.e., low, lower middle, and upper middle-income) for the years 2000, 2005, 2010 and 2015. Results DTP3 coverage in the African Region increased from 52% in 2000 to 76% in 2015,and MCV1 coverage increased from 53% to 74% during the same period, but with considerable differences among countries. Thirty-six African Region countries were low income in 2000 with an average DTP3 coverage of 50% while 26 were low income in 2015 with an average coverage of 80%. Five countries were lower middle-income in 2000 with an average DTP3 coverage of 84% while 12 were lower middle-income in 2015 with an average coverage of 69%. Five countries were upper middle-income in 2000 with an average DTP3 coverage of 73% and eight were upper middle-income in 2015 with an average coverage of 76%. Conclusion Disparities in vaccination coverage by country persist in the African Region, with countries that were lower middle-income having the lowest coverage on average in 2015. Monitoring and addressing these disparities is essential for meeting global immunization targets. PMID:29296140
NASA Astrophysics Data System (ADS)
Gutman, G.; Csiszar, I.
2012-04-01
The global, long-term effects of fires are not well understood and we are learning more every year about its global impacts and potential feedbacks to climate change. The frequency, intensity, severity, and emissions of fires may be changing as a result of climate warming as has been manifested by the observations in northern Eurasia. The climate-fire interaction may produce important societal and environmental impacts in the long run. NASA and NOAA have been developing long-term fire datasets and improving systems to monitor active fires, study fire severity, fire growth, emissions into the atmosphere, and fire effects on carbon stocks. Almost every year there are regions in the world that experience particularly severe fires. For example, less than two years ago the European part of Russia was the focus of attention due to the anomalous heat and dry wave with record high temperatures that caused wildfires rage for weeks and that led to thousands of deaths. The fires also have spread to agricultural land and damaged crops, causing sharp increases of global wheat commodity prices. Remote sensing observations are widely used to monitor fire occurrence, fire spread; smoke dispersion, and atmospheric pollutant levels. In the context of climate warming and acute interest to large-scale emissions from various land-cover disturbances studying spatial-temporal dynamics of forest fire activity is critical. NASA supports several activities related to fires and the Earth system. These include GOFC-GOLD Fire Project Office at University of Maryland and the Rapid Response System for global fire monitoring. NASA has funded many research projects on biomass burning, which cover various geographic regions of the world and analyze impacts of fires on atmospheric carbon in support of REDD initiative, as well as on atmospheric pollution with smoke. Monitoring active fires, studying their severity and burned areas, and estimating fire-induced atmospheric emissions has been the subject of several research projects in the NASA LCLUC program over the globe, and, in particular, in Northern Eurasia. As an operational agency, NOAA puts global fire monitoring as a priority and supports related GCOS, CEOS and GOFC-GOLD objectives. NOAA developed an operational quasi-global fire monitoring system using geostationary satellites that provides coverage over parts of Northern Eurasia. Fire products from the VIIRS (Visible Infrared Imager Radiometer Suite) sensor on the NPP (NPOESS Preparatory Project) satellite, launched in October 2011, and on subsequent JPSS satellites will ensure high quality global fire monitoring and will extent the AVHRR- and MODIS-based fire data record over Northern Eurasia. This overview presents an update of NASA's and NOAA's fire monitoring capability and scientific achievements on fire-climate interactions. We will illustrate how combination of coarse spatial resolution polar orbiting satellite observations are combined with moderate spatial resolution observations to better monitor the location of fires and burned areas. While coarse resolution data have been more or less easily available, the utility of moderate resolution Landsat data has increased tremendously during the past couple of years once the data became freely available. Data fusion from polar orbiting and geostationary satellites will be discussed.
NASA Astrophysics Data System (ADS)
Yao, Wei; van Aardt, Jan; Messinger, David
2017-05-01
The Hyperspectral Infrared Imager (HyspIRI) mission aims to provide global imaging spectroscopy data to the benefit of especially ecosystem studies. The onboard spectrometer will collect radiance spectra from the visible to short wave infrared (VSWIR) regions (400-2500 nm). The mission calls for fine spectral resolution (10 nm band width) and as such will enable scientists to perform material characterization, species classification, and even sub-pixel mapping. However, the global coverage requirement results in a relatively low spatial resolution (GSD 30m), which restricts applications to objects of similar scales. We therefore have focused on the assessment of sub-pixel vegetation structure from spectroscopy data in past studies. In this study, we investigate the development or reconstruction of higher spatial resolution imaging spectroscopy data via fusion of multi-temporal data sets to address the drawbacks implicit in low spatial resolution imagery. The projected temporal resolution of the HyspIRI VSWIR instrument is 15 days, which implies that we have access to as many as six data sets for an area over the course of a growth season. Previous studies have shown that select vegetation structural parameters, e.g., leaf area index (LAI) and gross ecosystem production (GEP), are relatively constant in summer and winter for temperate forests; we therefore consider the data sets collected in summer to be from a similar, stable forest structure. The first step, prior to fusion, involves registration of the multi-temporal data. A data fusion algorithm then can be applied to the pre-processed data sets. The approach hinges on an algorithm that has been widely applied to fuse RGB images. Ideally, if we have four images of a scene which all meet the following requirements - i) they are captured with the same camera configurations; ii) the pixel size of each image is x; and iii) at least r2 images are aligned on a grid of x/r - then a high-resolution image, with a pixel size of x/r, can be reconstructed from the multi-temporal set. The algorithm was applied to data from NASA's classic Airborne Visible and Infrared Imaging Spectrometer (AVIRIS-C; GSD 18m), collected between 2013-2015 (summer and fall) over our study area (NEON's Southwest Pacific Domain; Fresno, CA) to generate higher spatial resolution imagery (GSD 9m). The reconstructed data set was validated via comparison to NEON's imaging spectrometer (NIS) data (GSD 1m). The results showed that algorithm worked well with the AVIRIS-C data and could be applied to the HyspIRI data.
Miles, Melody; Ryman, Tove K; Dietz, Vance; Zell, Elizabeth; Luman, Elizabeth T
2013-03-15
Immunization programs frequently rely on household vaccination cards, parental recall, or both to calculate vaccination coverage. This information is used at both the global and national level for planning and allocating performance-based funds. However, the validity of household-derived coverage sources has not yet been widely assessed or discussed. To advance knowledge on the validity of different sources of immunization coverage, we undertook a global review of literature. We assessed concordance, sensitivity, specificity, positive and negative predictive value, and coverage percentage point difference when subtracting household vaccination source from a medical provider source. Median coverage difference per paper ranged from -61 to +1 percentage points between card versus provider sources and -58 to +45 percentage points between recall versus provider source. When card and recall sources were combined, median coverage difference ranged from -40 to +56 percentage points. Overall, concordance, sensitivity, specificity, positive and negative predictive value showed poor agreement, providing evidence that household vaccination information may not be reliable, and should be interpreted with care. While only 5 papers (11%) included in this review were from low-middle income countries, low-middle income countries often rely more heavily on household vaccination information for decision making. Recommended actions include strengthening quality of child-level data and increasing investments to improve vaccination card availability and card marking. There is also an urgent need for additional validation studies of vaccine coverage in low and middle income countries. Copyright © 2013. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Lecompte, M. A.; Heaps, J. F.; Williams, F. H.
Imaging the earth from Geostationary Earth Orbit (GEO) allows frequent updates of environmental conditions within an observable hemisphere at time and spatial scales appropriate to the most transient observable terrestrial phenomena. Coverage provided by current GEO Meteorological Satellites (METSATS) fails to fully exploit this advantage due primarily to obsolescent technology and also institutional inertia. With the full benefit of GEO based imaging unrealized, rapidly evolving phenomena, occurring at the smallest spatial and temporal scales that frequently have significant environmental impact remain unobserved. These phenomena may be precursors for the most destructive natural processes that adversely effect society. Timely distribution of information derived from "real-time" observations thus may provide opportunities to mitigate much of the damage to life and property that would otherwise occur. AstroVision International's AVStar Earth monitoring system is designed to overcome the current limitations if GEO Earth coverage and to provide real time monitoring of changes to the Earth's complete atmospheric, land and marine surface environments including fires, volcanic events, lightning and meteoritic events on a "live," true color, and multispectral basis. The understanding of severe storm dynamics and its coupling to the earth's electro-sphere will be greatly enhanced by observations at unprecedented sampling frequencies and spatial resolution. Better understanding of these natural phenomena and AVStar operational real-time coverage may also benefit society through improvements in severe weather prediction and warning. AstroVision's AVStar system, designed to provide this capability with the first of a constellation of GEO- based commercial environmental monitoring satellites to be launched in late 2003 will be discussed, including spatial and temporal resolution, spectral coverage with applications and an inventory of the potential benefits to society, science, commerce and education.
An improved rainfall disaggregation technique for GCMs
NASA Astrophysics Data System (ADS)
Onof, C.; Mackay, N. G.; Oh, L.; Wheater, H. S.
1998-08-01
Meteorological models represent rainfall as a mean value for a grid square so that when the latter is large, a disaggregation scheme is required to represent the spatial variability of rainfall. In general circulation models (GCMs) this is based on an assumption of exponentiality of rainfall intensities and a fixed value of areal rainfall coverage, dependent on rainfall type. This paper examines these two assumptions on the basis of U.K. and U.S. radar data. Firstly, the coverage of an area is strongly dependent on its size, and this dependence exhibits a scaling law over a range of sizes. Secondly, the coverage is, of course, dependent on the resolution at which it is measured, although this dependence is weak at high resolutions. Thirdly, the time series of rainfall coverages has a long-tailed autocorrelation function which is comparable to that of the mean areal rainfalls. It is therefore possible to reproduce much of the temporal dependence of coverages by using a regression of the log of the mean rainfall on the log of the coverage. The exponential assumption is satisfactory in many cases but not able to reproduce some of the long-tailed dependence of some intensity distributions. Gamma and lognormal distributions provide a better fit in these cases, but they have their shortcomings and require a second parameter. An improved disaggregation scheme for GCMs is proposed which incorporates the previous findings to allow the coverage to be obtained for any area and any mean rainfall intensity. The parameters required are given and some of their seasonal behavior is analyzed.
Systematical estimation of GPM-based global satellite mapping of precipitation products over China
NASA Astrophysics Data System (ADS)
Zhao, Haigen; Yang, Bogang; Yang, Shengtian; Huang, Yingchun; Dong, Guotao; Bai, Juan; Wang, Zhiwei
2018-03-01
As the Global Precipitation Measurement (GPM) Core Observatory satellite continues its mission, new version 6 products for Global Satellite Mapping of Precipitation (GSMaP) have been released. However, few studies have systematically evaluated the GSMaP products over mainland China. This study quantitatively evaluated three GPM-based GSMaP version 6 precipitation products for China and eight subregions referring to the Chinese daily Precipitation Analysis Product (CPAP). The GSMaP products included near-real-time (GSMaP_NRT), microwave-infrared reanalyzed (GSMaP_MVK), and gauge-adjusted (GSMaP_Gau) data. Additionally, the gauge-adjusted Integrated Multi-Satellite Retrievals for Global Precipitation Measurement Mission (IMERG_Gau) was also assessed and compared with GSMaP_Gau. The analyses of the selected daily products were carried out at spatiotemporal resolutions of 1/4° for the period of March 2014 to December 2015 in consideration of the resolution of CPAP and the consistency of the coverage periods of the satellite products. The results indicated that GSMaP_MVK and GSMaP_NRT performed comparably and underdetected light rainfall events (< 5 mm/day) in the northwest and northeast of China. All the statistical metrics of GSMaP_MVK were slightly improved compared with GSMaP_NRT in spring, autumn, and winter, whereas GSMaP_NRT demonstrated superior Pearson linear correlation coefficient (CC), fractional standard error (FSE), and root-mean-square error (RMSE) metrics during the summer. Compared with GSMaP_NRT and GSMaP_MVK, GSMaP_Gau possessed significantly improved metrics over mainland China and the eight subregions and performed better in terms of CC, RMSE, and FSE but underestimated precipitation to a greater degree than IMERG_Gau. As a quantitative assessment of the GPM-era GSMaP products, these validation results will supply helpful references for both end users and algorithm developers. However, the study findings need to be confirmed over a longer future study period when the longer-period IMERG retrospectively-processed data are available.
Remote Sensing of Cloud, Aerosol, and Water Vapor Properties from MODIS
NASA Technical Reports Server (NTRS)
King, Michael D.
2001-01-01
MODIS is an earth-viewing cross-track scanning spectroradiometer launched on the Terra satellite in December 1999. MODIS scans a swath width sufficient to provide nearly complete global coverage every two days from a polar-orbiting, sun-synchronous, platform at an altitude of 705 km, and provides images in 36 spectral bands from 0.415 to 14.235 microns with spatial resolutions of 250 m (2 bands), 500 m (5 bands) and 1000 m (29 bands). These bands have been carefully selected to enable advanced studies of land, ocean, and atmospheric processes. In this presentation I will review the comprehensive set of remote sensing algorithms that have been developed for the remote sensing of atmospheric properties using MODIS data, placing primary emphasis on the principal atmospheric applications of: (1) developing a cloud mask for distinguishing clear sky from clouds, (2) retrieving global cloud radiative and microphysical properties, including cloud top pressure and temperature, effective emissivity, cloud optical thickness, thermodynamic phase, and effective radius, (3) monitoring tropospheric aerosol optical thickness over the land and ocean and aerosol size distribution over the ocean, (4) determining atmospheric profiles of moisture and temperature, and (5) estimating column water amount. The physical principles behind the determination of each of these atmospheric products will be described, together with an example of their application using MODIS observations. All products are archived into two categories: pixel-level retrievals (referred to as Level-2 products) and global gridded products at a latitude and longitude resolution of 1 deg (Level-3 products). An overview of the MODIS atmosphere algorithms and products, status, validation activities, and early level-2 and -3 results will be presented. Finally, I will present some highlights from the land and ocean algorithms developed for processing global MODIS observations, including: (1) surface reflectance, (2) vegetation indices, leaf area index, and FPAR, (3) albedo and nadir BRDF-adjusted reflectance, (4) normalized water-leaving radiance, (5) chlorophyll-a concentration, and (6) sea surface temperature.
[Winter wheat area estimation with MODIS-NDVI time series based on parcel].
Li, Le; Zhang, Jin-shui; Zhu, Wen-quan; Hu, Tan-gao; Hou, Dong
2011-05-01
Several attributes of MODIS (moderate resolution imaging spectrometer) data, especially the short temporal intervals and the global coverage, provide an extremely efficient way to map cropland and monitor its seasonal change. However, the reliability of their measurement results is challenged because of the limited spatial resolution. The parcel data has clear geo-location and obvious boundary information of cropland. Also, the spectral differences and the complexity of mixed pixels are weak in parcels. All of these make that area estimation based on parcels presents more advantage than on pixels. In the present study, winter wheat area estimation based on MODIS-NDVI time series has been performed with the support of cultivated land parcel in Tongzhou, Beijing. In order to extract the regional winter wheat acreage, multiple regression methods were used to simulate the stable regression relationship between MODIS-NDVI time series data and TM samples in parcels. Through this way, the consistency of the extraction results from MODIS and TM can stably reach up to 96% when the amount of samples accounts for 15% of the whole area. The results shows that the use of parcel data can effectively improve the error in recognition results in MODIS-NDVI based multi-series data caused by the low spatial resolution. Therefore, with combination of moderate and low resolution data, the winter wheat area estimation became available in large-scale region which lacks completed medium resolution images or has images covered with clouds. Meanwhile, it carried out the preliminary experiments for other crop area estimation.
Gutierrez, Hialy; Shewade, Ashwini; Dai, Minghan; Mendoza-Arana, Pedro; Gómez-Dantés, Octavio; Jain, Nishant; Khonelidze, Irma; Nabyonga-Orem, Juliet; Saleh, Karima; Teerawattananon, Yot; Nishtar, Sania; Hornberger, John
2015-08-01
Lessons learned by countries that have successfully implemented coverage schemes for health services may be valuable for other countries, especially low- and middle-income countries (LMICs), which likewise are seeking to provide/expand coverage. The research team surveyed experts in population health management from LMICs for information on characteristics of health care coverage schemes and factors that influenced decision-making processes. The level of coverage provided by the different schemes varied. Nearly all the health care coverage schemes involved various representatives and stakeholders in their decision-making processes. Maternal and child health, cardiovascular diseases, cancer, and HIV were among the highest priorities guiding coverage development decisions. Evidence used to inform coverage decisions included medical literature, regional and global epidemiology, and coverage policies of other coverage schemes. Funding was the most commonly reported reason for restricting coverage. This exploratory study provides an overview of health care coverage schemes from participating LMICs and contributes to the scarce evidence base on coverage decision making. Sharing knowledge and experiences among LMICs can support efforts to establish systems for accessible, affordable, and equitable health care.
Sun, Shaojie; Hu, Chuanmin; Feng, Lian; Swayze, Gregg A.; Holmes, Jamie; Graettinger, George; MacDonald, Ian R.; Garcia, Oscar; Leifer, Ira
2016-01-01
Using fine spatial resolution (~ 7.6 m) hyperspectral AVIRIS data collected over the Deepwater Horizon oil spill in the Gulf of Mexico, we statistically estimated slick lengths, widths and length/width ratios to characterize oil slick morphology for different thickness classes. For all AVIRIS-detected oil slicks (N = 52,100 continuous features) binned into four thickness classes (≤ 50 μm but thicker than sheen, 50–200 μm, 200–1000 μm, and > 1000 μm), the median lengths, widths, and length/width ratios of these classes ranged between 22 and 38 m, 7–11 m, and 2.5–3.3, respectively. The AVIRIS data were further aggregated to 30-m (Landsat resolution) and 300-m (MERIS resolution) spatial bins to determine the fractional oil coverage in each bin. Overall, if 50% fractional pixel coverage were to be required to detect oil with thickness greater than sheen for most oil containing pixels, a 30-m resolution sensor would be needed.
Strengthening routine immunization systems to improve global vaccination coverage.
Sodha, S V; Dietz, V
2015-03-01
Global coverage with the third dose of diphtheria-tetanus-pertussis vaccine among children under 1 year of age stagnated at ∼ 83-84% during 2008-13. Annual World Health Organization and UNICEF-derived national vaccination coverage estimates. Incomplete vaccination is associated with poor socioeconomic status, lower education, non-use of maternal-child health services, living in conflict-affected areas, missed immunization opportunities and cancelled vaccination sessions. Vaccination platforms must expand to include older ages including the second year of life. Immunization programmes, including eradication and elimination initiatives such as those for polio and measles, must integrate within the broader health system. The Global Vaccine Action Plan (GVAP) 2011-20 is a framework for strengthening immunization systems, emphasizing country ownership, shared responsibility, equity, integration, sustainability and innovation. Immunization programmes should identify, monitor and evaluate gaps and interventions within the GVAP framework. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
NASA Astrophysics Data System (ADS)
Kim, S.; Kim, H.; Choi, M.; Kim, K.
2016-12-01
Estimating spatiotemporal variation of soil moisture is crucial to hydrological applications such as flood, drought, and near real-time climate forecasting. Recent advances in space-based passive microwave measurements allow the frequent monitoring of the surface soil moisture at a global scale and downscaling approaches have been applied to improve the spatial resolution of passive microwave products available at local scale applications. However, most downscaling methods using optical and thermal dataset, are valid only in cloud-free conditions; thus renewed downscaling method under all sky condition is necessary for the establishment of spatiotemporal continuity of datasets at fine resolution. In present study Support Vector Machine (SVM) technique was utilized to downscale a satellite-based soil moisture retrievals. The 0.1 and 0.25-degree resolution of daily Land Parameter Retrieval Model (LPRM) L3 soil moisture datasets from Advanced Microwave Scanning Radiometer 2 (AMSR2) were disaggregated over Northeast Asia in 2015. Optically derived estimates of surface temperature (LST), normalized difference vegetation index (NDVI), and its cloud products were obtained from MODerate Resolution Imaging Spectroradiometer (MODIS) for the purpose of downscaling soil moisture in finer resolution under all sky condition. Furthermore, a comparison analysis between in situ and downscaled soil moisture products was also conducted for quantitatively assessing its accuracy. Results showed that downscaled soil moisture under all sky condition not only preserves the quality of AMSR2 LPRM soil moisture at 1km resolution, but also attains higher spatial data coverage. From this research we expect that time continuous monitoring of soil moisture at fine scale regardless of weather conditions would be available.
2017 Updates: Earth Gravitational Model 2020
NASA Astrophysics Data System (ADS)
Barnes, D. E.; Holmes, S. A.; Ingalls, S.; Beale, J.; Presicci, M. R.; Minter, C.
2017-12-01
The National Geospatial-Intelligence Agency [NGA], in conjunction with its U.S. and international partners, has begun preliminary work on its next Earth Gravitational Model, to replace EGM2008. The new `Earth Gravitational Model 2020' [EGM2020] has an expected public release date of 2020, and will retain the same harmonic basis and resolution as EGM2008. As such, EGM2020 will be essentially an ellipsoidal harmonic model up to degree (n) and order (m) 2159, but will be released as a spherical harmonic model to degree 2190 and order 2159. EGM2020 will benefit from new data sources and procedures. Updated satellite gravity information from the GOCE and GRACE mission, will better support the lower harmonics, globally. Multiple new acquisitions (terrestrial, airborne and shipborne) of gravimetric data over specific geographical areas (Antarctica, Greenland …), will provide improved global coverage and resolution over the land, as well as for coastal and some ocean areas. Ongoing accumulation of satellite altimetry data as well as improvements in the treatment of this data, will better define the marine gravity field, most notably in polar and near-coastal regions. NGA and partners are evaluating different approaches for optimally combining the new GOCE/GRACE satellite gravity models with the terrestrial data. These include the latest methods employing a full covariance adjustment. NGA is also working to assess systematically the quality of its entire gravimetry database, towards correcting biases and other egregious errors. Public release number 15-564