An Inversion Analysis of Recent Variability in CO2 Fluxes Using GOSAT and In Situ Observations

NASA Astrophysics Data System (ADS)

Wang, J. S.; Kawa, S. R.; Baker, D. F.; Collatz, G. J.

2016-12-01

About one-half of the global CO2 emissions from fossil fuel combustion and deforestation accumulates in the atmosphere, where it contributes to global warming. The rest is taken up by vegetation and the ocean. The precise contribution of the two sinks and their location and year-to-year variability are not well understood. We use two different approaches, batch Bayesian synthesis inversion and variational data assimilation, to deduce the global spatiotemporal distributions of CO2 fluxes during 2009-2010. One of our objectives is to assess different sources of uncertainties in inferred fluxes, including uncertainties in prior flux estimates and observations, and differences in inversion techniques. For prior constraints, we utilize fluxes and uncertainties from the CASA-GFED model of the terrestrial biosphere and biomass burning driven by satellite observations. We also use measurement-based ocean flux estimates and fixed fossil CO2 emissions. Our inversions incorporate column CO2 measurements from the GOSAT satellite (ACOS retrieval, bias-corrected) and in situ observations (individual flask and afternoon-average continuous observations) to estimate fluxes in 108 regions over 8-day intervals for the batch inversion and at 3° x 3.75° weekly for the variational system. Relationships between fluxes and atmospheric concentrations are derived consistently for the two inversion systems using the PCTM transport model with MERRA meteorology. We compare the posterior fluxes and uncertainties derived using different data sets and the two inversion approaches, and evaluate the posterior atmospheric concentrations against independent data including aircraft measurements. The optimized fluxes generally resemble each other and those from other studies. For example, a GOSAT-only inversion suggests a shift in the global sink from the tropics/south to the north relative to the prior and to an in-situ-only inversion. The posterior fluxes of the GOSAT inversion are better

Recent scientific achievements by GOSAT and the status of GOSAT-2 preparation

NASA Astrophysics Data System (ADS)

Imasu, R.; Matsunaga, T.; Nakajima, M.; Inoue, G.

2017-12-01

GOSAT has been normally operated since 2009 to provide worldwide scientists with long-term CO2 and CH4 data in uniform quality. Recently, we extended targeting observation over Tokyo-city to be evenly spaced to cover the whole city, and started targeting at Ulaanbaatar, Mongolia for monitoring CO2 emissions from the city. Based on the accumulated observational data, research targets and areas have been widened and analysis approaches have become divers. By combining Eulerian and Lagrangian models, the footprints of short-term variations in XCO2 were determined (Belikov et al., 2017). To evaluate anthropogenic methane emission inventory in various special scales, emission signatures from GOSAT XCH4 were extracted based on high-resolution transport simulations (Janardanan et al, submitted). Saitoh et al. (in rev.) has validated CO2 and CH4 profiles retrieved from thermal infrared (TIR) spectra using aircraft profiles as well as level flight data intending to make them applicable to inverse analyses. Other minor constituents such as N2O (Kangah et al., 2016) and NH3 (Someya et al., in prep.) have been also retrieved from TIR spectra. Hardware development of the successor, GOSAT-2 has been almost completed. The satellite is scheduled to be launched in FY2018 expecting at least one year overlap with GOSAT. One of innovative techniques for GOSAT-2 is so called "intelligent pointing system" by which clear sky scenes can be dynamically selected based on onboard camera images. Demonstration of the system has been performed using airplane, and doubling of clear sky provability is expected. Another notable improvement is adding CO channel, which enable the detection of urban plumes and evaluation of combustion efficiency of biomass burning by simultaneous analyses with CO2. Improving S/N of detectors enables to expand the observational area toward higher latitudes, and widening of scan-angle limit increases the Sunglint probability. More precise detection of Solar Induced

Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data

NASA Astrophysics Data System (ADS)

Turner, A. J.; Jacob, D. J.; Wecht, K. J.; Maasakkers, J. D.; Lundgren, E.; Andrews, A. E.; Biraud, S. C.; Boesch, H.; Bowman, K. W.; Deutscher, N. M.; Dubey, M. K.; Griffith, D. W. T.; Hase, F.; Kuze, A.; Notholt, J.; Ohyama, H.; Parker, R.; Payne, V. H.; Sussmann, R.; Sweeney, C.; Velazco, V. A.; Warneke, T.; Wennberg, P. O.; Wunch, D.

2015-06-01

We use 2009-2011 space-borne methane observations from the Greenhouse Gases Observing SATellite (GOSAT) to estimate global and North American methane emissions with 4° × 5° and up to 50 km × 50 km spatial resolution, respectively. GEOS-Chem and GOSAT data are first evaluated with atmospheric methane observations from surface and tower networks (NOAA/ESRL, TCCON) and aircraft (NOAA/ESRL, HIPPO), using the GEOS-Chem chemical transport model as a platform to facilitate comparison of GOSAT with in situ data. This identifies a high-latitude bias between the GOSAT data and GEOS-Chem that we correct via quadratic regression. Our global adjoint-based inversion yields a total methane source of 539 Tg a-1 with some important regional corrections to the EDGARv4.2 inventory used as a prior. Results serve as dynamic boundary conditions for an analytical inversion of North American methane emissions using radial basis functions to achieve high resolution of large sources and provide error characterization. We infer a US anthropogenic methane source of 40.2-42.7 Tg a-1, as compared to 24.9-27.0 Tg a-1 in the EDGAR and EPA bottom-up inventories, and 30.0-44.5 Tg a-1 in recent inverse studies. Our estimate is supported by independent surface and aircraft data and by previous inverse studies for California. We find that the emissions are highest in the southern-central US, the Central Valley of California, and Florida wetlands; large isolated point sources such as the US Four Corners also contribute. Using prior information on source locations, we attribute 29-44 % of US anthropogenic methane emissions to livestock, 22-31 % to oil/gas, 20 % to landfills/wastewater, and 11-15 % to coal. Wetlands contribute an additional 9.0-10.1 Tg a-1.

Design and qualification of the interferometer for the GOSAT-2 spectrometer

NASA Astrophysics Data System (ADS)

Montembault, Yan; Moreau, Louis; Roux, Michel; Buijs, Henry; Soucy, Marc-André

2016-10-01

GOSAT-2 is the successor of the Greenhouse gases Observing SATellite (GOSAT, "IBUKI") launched in 2009 by Japan Aerospace Exploration Agency (JAXA). GOSAT-2 will continue and enhance space borne measurements of greenhouse gases started by GOSAT and monitor the impacts of climate change and human activities on the carbon cycle. It will also contribute to climate science and climate change related policies. The GOSAT-2 spacecraft will carry two earth observation instruments: FTS-2, the second generation of the TANSO-FTS and CAI-2, a Cloud and Aerosol Imager. Mitsubishi Electric Corporation is the prime contractor of GOSAT-2. Harris is the subcontractor of the spectrometer. ABB, who successfully designed, manufactured, and delivered the interferometer for the TANSO-FTS instrument for GOSAT, is currently delivering the modulator for the FTS-2 instrument to Mitsubishi Electric Corporation. Built on the TANSO-FTS heritage, FTS-2 is a thermal and near infrared sensor for carbon observation based on a Fourier transform spectrometer featuring larger optical throughput than TANSO-FTS. This paper presents an overview of the design of the FTS-2 interferometer as well as key qualification and performance verification activities conducted on the interferometer flight model.

Validation of XCO2 derived from SWIR of GOSAT TANSO-FTS with aircraft measurement data

NASA Astrophysics Data System (ADS)

Inoue, M.; Morino, I.; Uchino, O.; Miyamoto, Y.; Yoshida, Y.; Yokota, T.; Machida, T.; Sawa, Y.; Matsueda, H.; Sweeney, C.; Tans, P. P.; Andrews, A. E.; Patra, P. K.

2011-12-01

Column-averaged mixing ratios of carbon dioxide (XCO2) are retrieved from the Short-Wavelength InfraRed (SWIR) spectrum of Thermal And Near-infrared Sensor for carbon Observation - Fourier Transform Spectrometer (TANSO-FTS) onboard the Greenhouse gases Observing SATellite (GOSAT). They are compared with the aircraft data measured by the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, National Oceanic and Atmospheric Administration (NOAA), and National Institute for Environmental Studies (NIES). Because limited aircraft measurement was conducted within a few hours of the GOSAT overpass time, we prepared temporally interpolated aircraft-based XCO2 data by fitting with the function that contains yearly trend and annual/semiannual sinusoidal variations to compare with GOSAT XCO2. As for the GOSAT XCO2 data, those retrieved within ±2 degrees or ±5 degrees latitude/longitude box centered at each observation site were used. In order to compare the aircraft data with the satellite data, the GOSAT column averaging kernels (CAK) should be taken into account to calculate the aircraft-based XCO2. However, it is hard to apply GOSAT CAK with temporally interpolated aircraft data. Therefore, we evaluated the GOSAT CAK impact on the aircraft-based XCO2 calculation by using CONTRAIL data over Narita (35.8N, 140.4E) where the maximum temporally match-upped data are available. The difference in the aircraft-based XCO2 with and without GOSAT CAK is lower by approximately 0.3 ppm. Here, we made a comparison between GOSAT XCO2 and aircraft-based XCO2 without GOSAT CAK. Although GOSAT data are underestimated by approximately 7-9 ppm for comparison in every site, there is a good correlation between both datasets in some sites, such as high-latitude regions of North America, Europe, Siberia, and ocean regions. A direct comparison between GOSAT and aircraft XCO2 at all observation sites shows that GOSAT SWIR XCO2 is biased low by about 8 ppm.

Web-based data acquisition and management system for GOSAT validation Lidar data analysis

NASA Astrophysics Data System (ADS)

Okumura, Hiroshi; Takubo, Shoichiro; Kawasaki, Takeru; Abdullah, Indra N.; Uchino, Osamu; Morino, Isamu; Yokota, Tatsuya; Nagai, Tomohiro; Sakai, Tetsu; Maki, Takashi; Arai, Kohei

2012-11-01

An web-base data acquisition and management system for GOSAT (Greenhouse gases Observation SATellite) validation lidar data analysis is developed. The system consists of data acquisition sub-system (DAS) and data management sub-system (DMS). DAS written in Perl language acquires AMeDAS ground-level meteorological data, Rawinsonde upper-air meteorological data, ground-level oxidant data, skyradiometer data, skyview camera images, meteorological satellite IR image data and GOSAT validation lidar data. DMS written in PHP language demonstrates satellite-pass date and all acquired data.

Sensitivity Analysis for CO2 Retrieval using GOSAT-2 FTS-2 Simulator

NASA Astrophysics Data System (ADS)

Kamei, Akihide; Yoshida, Yukio; Dupuy, Eric; Yokota, Yasuhiro; Hiraki, Kaduo; Matsunaga, Tsuneo

2015-04-01

The Greenhouse Gases Observing Satellite (GOSAT), launched in 2009, is the world's first satellite dedicated to global greenhouse gases observation. GOSAT-2, the successor mission to GOSAT, is scheduled for launch in early 2018. The Fourier Transform Spectrometer-2 (FTS-2) is the primary sensor onboard GOSAT-2. It observes infrared light reflected and emitted from the Earth's surface and atmosphere. The FTS-2 obtains high resolution spectra using three bands in the near to short-wavelength infrared (SWIR) region and two bands in the thermal infrared (TIR) region. Column amounts and vertical profiles of carbon dioxide (CO2) and methane (CH4) are retrieved from the radiance spectra obtained with the SWIR and TIR bands, respectively. Further, compared to the FTS onboard the GOSAT, the FTS-2 has several improvements: 1) added spectral coverage in the SWIR region for carbon monoxide (CO) retrieval, 2) increased signal-to-noise ratio (SNR) for all bands, 3) extended range of along-track pointing angles for sunglint observations, 4) intelligent pointing to avoid cloud contamination. Since 2012, we have been developing a simulator software to simulate the spectral radiance data that will be acquired by the GOSAT-2 FTS-2. The purpose of the GOSAT-2 FTS-2 simulator is to analyze/optimize data with respect to the sensor specification, the parameters for Level 1 processing, and the improvement of the Level 2 algorithms. The GOSAT-2 FTS-2 simulator includes the six components: 1) overall control, 2) sensor carrying platform, 3) spectral radiance calculation, 4) Fourier Transform module, 5) Level 1B (L1B) processing, and 6) L1B data output. It has been installed on the GOSAT Research Computation Facility (GOSAT RCF), which is a high-performance and energy-efficient supercomputer. More realistic and faster simulations have been made possible by the improvement of the details of sensor characteristics, the sophistication of the data processing and algorithms, the addition of the

GOSAT Observations of Anthropogenic Emission of Carbon Dioxide and Methane

NASA Astrophysics Data System (ADS)

Janardanan Achari, R.; Maksyutov, S. S.; Oda, T.; Saito, M.; W Kaiser, J.; Ganshin, A.; Matsunaga, T.; Yoshida, Y.; Yokota, T.

2016-12-01

Carbon dioxide (CO2) and methane (CH4) are the most important greenhouse gases in terms of radiative forcing. Anthropogenic activities such as combustion of fossil fuel (for CO2) and gas leakage, animal agriculture, rice cultivation and landfill emissions (CH4), are considered to be major sources of those emissions. Still, emission data usually depend on national emission reports, which are seldom evaluated independently. Here we present a method for delineating anthropogenic contribution to global atmospheric CO2 (2009-2014) and CH4 (2009-2012) fields using GOSAT observations of column-average dry air mole fractions (XCO2 and XCH4) and atmospheric transport model simulations using high-resolution emission inventories. The CO2 and CH4 concentration enhancement due to anthropogenic activities, are estimated with the transport model at all GOSAT observation locations using high-resolution emission inventories (ODIAC for CO2 and EDGAR for CH4). Based on this estimate, using a threshold value, the observations are classified into two categories: data influenced by the anthropogenic sources and those not including them. To extract concentration enhancements due to the anthropogenic emissions, we define a clean background (the averaged values for the data free from contamination) in 10°×10° regions over the globe and are subtracted from the individual observational data including the anthropogenic contamination. Thus the anomalies contain contributions from anthropogenic sources. These anomalies are binned and analyzed for continental scale regions and countries. For CO2, we have found global and regional linear relationships between model and observed anomalies especially for Eurasia and North America. The analysis for East Asian region showed a systematic bias that is comparable in magnitude to the reported uncertainties in emission inventories in that region. In the case of CH4, we also found a good match between inventory-based estimates and GOSAT observations for

Estimating Amazonian methane emissions through 4D-Var inverse modelling with satellite observations from GOSAT and IASI

NASA Astrophysics Data System (ADS)

Wilson, C. J.; Chipperfield, M.; Gloor, M.; McNorton, J.; Miller, J. B.; Gatti, L. V.; Siddans, R.; Bloom, A. A.; Basso, L. S.; Boesch, H.; Parker, R.; Monks, S. A.

2015-12-01

observations prior to data assimilation, some high-methane events indicated by the observations are not captured by the model. We assimilate observations from the NOAA surface measurement network, from the AMAZONICA aircraft and from the GOSAT and IASI satellites, and find that tropical South American CH4 emissions approach 50 Tg(CH4)/yr.

Three-dimensional Distribution of Greenhouse Gas Concentrations over Megacities Observed by GOSAT

NASA Astrophysics Data System (ADS)

Kikuchi, N.; Kuze, A.; Kataoka, F.; Shiomi, K.; Hashimoto, M.; Suto, H.; Knuteson, R. O.; Iraci, L. T.; Yates, E. L.; Gore, W.; Tanaka, T.

2017-12-01

Since the launch in January 2009, TANSO-FTS onboard GOSAT continues to observe the global distribution of carbon dioxide (CO2) and methane (CH4) concentrations. The regular grid observation is the standard observation mode, because a reduction of the uncertainty in the surface fluxes of CO2 and CH4in a subcontinental scale is one of the prime objectives of GOSAT. To meet an increasing demand for monitoring the anthropogenic emission of the greenhouses gases from large cities, GOSAT has carried out extensive target mode observations over several megacities since 2016. Although the footprint of TANSO-FTS is relatively large, the flexible pointing mechanism enables us to cover a city and the surrounding area at the same time. Another advantage of GOSAT TANSO-FTS is that it measures both SWIR and TIR spectra at the same footprint. By adding TIR windows to the existing SWIR retrieval algorithm, we can get the degrees of freedom larger than 2 for CO2 concentrations. This means that we can retrieve not only the column averaged concentration of CO2 (XCO2), but also the two-layer structure of CO2 concentrations, independent of the a priori constraint. In this study, we present three-dimensional distributions of CO2 and CH4 retrieved from GOSAT observations over several megacities including New York City. Fig. 1 shows the seasonal variation of XCO2 over New York City in 2016 covered by 16 footprints of GOSAT observations. A three-dimensional representation of CO2 concentrations is shown in Fig. 2 observed on September 15, 2016. In this example, CO2 concentrations were lower in the lower atmosphere in most of GOSAT footprints, indicating that CO2 was depleted in the lower atmosphere as expected for the summer season. In the winter season, the CO2 concentrations were enhanced in the lower atmosphere as shown in Fig. 3. This example indicates that GOSAT can detect variations in both the column and the vertical structure of CO2 over megacities. Similar analyses are underway for

The current status of the mission instruments of GOSAT-2

NASA Astrophysics Data System (ADS)

Nakajima, Masakatsu; Yajima, Yukie; Hashimoto, Makiko; Shiomi, Kei; Suto, Hiroshi; Imai, Hiroko

2017-04-01

The GOSAT-2 is the successor satellite to the GOSAT which is the satellite dedicated to the measurements of the greenhouse gases such as carbon dioxide and methane. GOSAT was launched in January of 2009 and has been operated for about seven years. The development of the GOSAT-2 has been continued for three years, and currently the proto-flight model is under manufacturing. The mission instruments of the GOSAT-2 are TANSO-FTS-2 and TANSO-CAI-2. TANSO-FTS-2 is the Fourier Transform Spectrometer observing greenhouse gases such as Carbon Dioxide and Methane and TANSO-CAI-2 is the imager observing the aerosols and clouds to compensate the TANSO-FTS-2 data and to grasp the movements of the aerosols such as PM2.5. The mission instruments will adopt the same kinds of instruments as GOSAT. But some improvements will be carried. Based on the results of the critical design, the manufacturing of the proto-flight model was started and through the manufacturing, the gap has emerged between the design and manufacturing. Especially, the results of the polarization sensitivity of the TANSO-CAI-2 was lower than 3% which is the requirements and the results of the test manufacturing has shown that it has been over than 40%. The root cause of this anomaly was that the thickness of the anti-reflecting coating had varied from place to place. Therefore the design of the thickness of the anti-reflecting coating has been changed with consideration for the difference of the thickness of the coat between the center and edge of the lens. And we could meet the polarization sensitivity requirement. In this presentation, the root cause and the investigation process of the polarization sensitivity anomaly will be presented as well as the current status of the manufacturing of the mission instruments of GOSAT-2.

Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data

NASA Astrophysics Data System (ADS)

Turner, A. J.; Jacob, D. J.; Wecht, K. J.; Maasakkers, J. D.; Biraud, S. C.; Boesch, H.; Bowman, K. W.; Deutscher, N. M.; Dubey, M. K.; Griffith, D. W. T.; Hase, F.; Kuze, A.; Notholt, J.; Ohyama, H.; Parker, R.; Payne, V. H.; Sussmann, R.; Velazco, V. A.; Warneke, T.; Wennberg, P. O.; Wunch, D.

2015-02-01

We use 2009-2011 space-borne methane observations from the Greenhouse Gases Observing SATellite (GOSAT) to constrain global and North American inversions of methane emissions with 4° × 5° and up to 50 km × 50 km spatial resolution, respectively. The GOSAT data are first evaluated with atmospheric methane observations from surface networks (NOAA, TCCON) and aircraft (NOAA/DOE, HIPPO), using the GEOS-Chem chemical transport model as a platform to facilitate comparison of GOSAT with in situ data. This identifies a high-latitude bias between the GOSAT data and GEOS-Chem that we correct via quadratic regression. The surface and aircraft data are subsequently used for independent evaluation of the methane source inversions. Our global adjoint-based inversion yields a total methane source of 539 Tg a-1 and points to a large East Asian overestimate in the EDGARv4.2 inventory used as a prior. Results serve as dynamic boundary conditions for an analytical inversion of North American methane emissions using radial basis functions to achieve high resolution of large sources and provide full error characterization. We infer a US anthropogenic methane source of 40.2-42.7 Tg a-1, as compared to 24.9-27.0 Tg a-1 in the EDGAR and EPA bottom-up inventories, and 30.0-44.5 Tg a-1 in recent inverse studies. Our estimate is supported by independent surface and aircraft data and by previous inverse studies for California. We find that the emissions are highest in the South-Central US, the Central Valley of California, and Florida wetlands, large isolated point sources such as the US Four Corners also contribute. We attribute 29-44% of US anthropogenic methane emissions to livestock, 22-31% to oil/gas, 20% to landfills/waste water, and 11-15% to coal with an additional 9.0-10.1 Tg a-1 source from wetlands.

Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data

DOE PAGES

Turner, A. J.; Jacob, D. J.; Wecht, K. J.; ...

2015-06-30

We use 2009–2011 space-borne methane observations from the Greenhouse Gases Observing SATellite (GOSAT) to estimate global and North American methane emissions with 4° × 5° and up to 50 km × 50 km spatial resolution, respectively. GEOS-Chem and GOSAT data are first evaluated with atmospheric methane observations from surface and tower networks (NOAA/ESRL, TCCON) and aircraft (NOAA/ESRL, HIPPO), using the GEOS-Chem chemical transport model as a platform to facilitate comparison of GOSAT with in situ data. This identifies a high-latitude bias between the GOSAT data and GEOS-Chem that we correct via quadratic regression. Our global adjoint-based inversion yields a totalmore » methane source of 539 Tg a −1 with some important regional corrections to the EDGARv4.2 inventory used as a prior. Results serve as dynamic boundary conditions for an analytical inversion of North American methane emissions using radial basis functions to achieve high resolution of large sources and provide error characterization. We infer a US anthropogenic methane source of 40.2–42.7 Tg a -1, as compared to 24.9–27.0 Tg a -1 in the EDGAR and EPA bottom-up inventories, and 30.0–44.5 Tg a -1 in recent inverse studies. Our estimate is supported by independent surface and aircraft data and by previous inverse studies for California. We find that the emissions are highest in the southern–central US, the Central Valley of California, and Florida wetlands; large isolated point sources such as the US Four Corners also contribute. Using prior information on source locations, we attribute 29–44 % of US anthropogenic methane emissions to livestock, 22–31 % to oil/gas, 20 % to landfills/wastewater, and 11–15 % to coal. Wetlands contribute an additional 9.0–10.1 Tg a -1.« less

Estimating global and North American methane emissions with high spatial resolution using GOSAT satellite data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, A. J.; Jacob, D. J.; Wecht, K. J.

2015-02-18

We use 2009–2011 space-borne methane observations from the Greenhouse Gases Observing SATellite (GOSAT) to constrain global and North American inversions of methane emissions with 4° × 5° and up to 50 km × 50 km spatial resolution, respectively. The GOSAT data are first evaluated with atmospheric methane observations from surface networks (NOAA, TCCON) and aircraft (NOAA/DOE, HIPPO), using the GEOS-Chem chemical transport model as a platform to facilitate comparison of GOSAT with in situ data. This identifies a high-latitude bias between the GOSAT data and GEOS-Chem that we correct via quadratic regression. The surface and aircraft data are subsequently usedmore » for independent evaluation of the methane source inversions. Our global adjoint-based inversion yields a total methane source of 539 Tg a −1 and points to a large East Asian overestimate in the EDGARv4.2 inventory used as a prior. Results serve as dynamic boundary conditions for an analytical inversion of North American methane emissions using radial basis functions to achieve high resolution of large sources and provide full error characterization. We infer a US anthropogenic methane source of 40.2–42.7 Tg a −1, as compared to 24.9–27.0 Tg a −1 in the EDGAR and EPA bottom-up inventories, and 30.0–44.5 Tg a −1 in recent inverse studies. Our estimate is supported by independent surface and aircraft data and by previous inverse studies for California. We find that the emissions are highest in the South-Central US, the Central Valley of California, and Florida wetlands, large isolated point sources such as the US Four Corners also contribute. We attribute 29–44% of US anthropogenic methane emissions to livestock, 22–31% to oil/gas, 20% to landfills/waste water, and 11–15% to coal with an additional 9.0–10.1 Tg a −1 source from wetlands.« less

The long term trend of carbon dioxide and solar-induced chlorophyll fluorescence over selected sites using GOSAT target observation data

NASA Astrophysics Data System (ADS)

Kataoka, F.; Higuchi, R.; Kuze, A.; Shiomi, K.

2017-12-01

The Greenhouse gases Observing SATellite (GOSAT) is designed to measure the concentration of major greenhouse gases from space. GOSAT carry the Fourier-Transform Spectrometer, which have three shortwave infrared (SWIR) bands and one thermal infrared (TIR) band. The SWIR bands correspond to the O2A band (0.76 mm), weak-CO2 (1.6 mm) and strong-CO2 (2.0 mm). The SWIR bands observe the backscattered sunlight from surface and retrieve the column-averaged dry air mole fraction of carbon dioxide and methane. The 0.76 mm band can also detect the solar-induced chlorophyll fluorescence (SIF) using high spectral-resolution spectra in O2A band and solar absorption feature (Fraunhofer lines). GOSAT have operated more than 8 years and targeted various kinds of land-cover area (forest, grass, desert, etc.). The long term CO2 and SIF data set potential to address the rate of CO2 uptake through plant photosynthesis. In this work, we evaluated a trend and seasonal fluctuation components of CO2 and SIF using the liner and trigonometric functions fitting. We analyzed the amplitude and phase of the CO2 and SIF seasonal variation and anomalies over selected sites. Spatial distribution from target observation dataset which consist of 16 point per site using an agile pointing system over megacity is presented together with wind data. The data is available from the GOSAT trend viewer at http://www.eorc.jaxa.jp/GOSAT/CO2_monitor/.

Algorithm development for the TIR bands of GOSAT-2/TANSO-FTS-2: lessons from GOSAT/TANSO-FTS TIR CO2 and CH4 measurement

NASA Astrophysics Data System (ADS)

Saitoh, N.; Yamada, A.; Itatsu, T.; Imasu, R.; Shiomi, K.; Niwa, Y.

2017-12-01

Greenhouse Gases Observing Satellite-2 (GOSAT-2), the successor of GOSAT, is planned to be launched in a year or so later. Thermal and Near Infrared Sensor for Carbon Observation (TANSO)-Fourier Transform Spectrometer-2 (FTS-2) on board the GOSAT-2 has two bands in the thermal infrared (TIR) region from 5.6 to 14.3 μm. We have developed an algorithm to retrieve CO2 and CH4 vertical profiles from the GOSAT/TANSO-FTS TIR band [Saitoh et al., 2009; 2016] and performed validation analysis for the TANSO-FTS TIR CO2 and CH4 products. Saitoh et al. [2016, 2017] showed that TANSO-FTS TIR V1 CO2 data had a seasonal- and regional-dependent negative bias in the upper troposphere and lower stratosphere and a consistent negative bias in the lower and middle troposphere. Holl et al. [2016], Zou et al. [2016], and Olsen et al. [2017] evaluated the data quality of the TANSO-FTS TIR V1 CH4 product through intercomparisons between TANSO-FTS and other satellite-borne and ground-based instruments; their results were generally consistent with comparison results of the V1 CH4 product with aircraft CH4 data [Saitoh et al., in preparation]. GOSAT/TANSO-FTS TIR N2O data, a by-product of the TIR V1 CH4 data, captured enhancement of N2O concentrations over the Mediterranean Sea associated with Asian monsoon circulation in spite of low signal-to-noise ratio (SNR) of TANSO-FTS 7-μm CH4 band [Kangah et al., 2017]. The SNR of the TIR bands of GOSAT-2/TANSO-FTS-2 are expected to be larger than that of TANSO-FTS especially at the 7-μm CH4 band. Based on the TANSO-FTS TIR V1 algorithm, we are now developing a retrieval algorithm for CO2, CH4, and other trace gases from the two TIR bands of GOSAT-2/TANSO-FTS-2. We have performed retrieval simulations using outputs from the Nonhydrostatic Icosahedral Atmospheric Model (NICAM)-based Transport Model (TM) [Niwa et al., 2011; 2017], which will be used as a priori data for the retrieval processing of GOSAT-2/TANSO-FTS-2.

Analysis of uncertainties in GOSAT-inferred regional CO2 fluxes

NASA Astrophysics Data System (ADS)

Ishizawa, M.; Shirai, T.; Maksyutov, S. S.; Yoshida, Y.; Morino, I.; Inoue, M.; Nakatsuru, T.; Uchino, O.; Mabuchi, K.

2016-12-01

Satellite-based CO2 measurements have potential for improving our understanding global carbon cycle because of more spatiotemporal coverage than those from ground-based observations. Since the Greenhouse gases Observing Satellite (GOSAT) was launched in January 2009, it has been measuring the column-average dry air-mole function of CO2 (XCO2) from the space. To utilize the GOSAT XCO2 for better CO2 flux estimates, several challenges should be overcome. Systematic errors (biases) in XCO2 retrievals are a major factor which leads to large differences among inverted CO2 fluxes. Temporally variable data coverage and density are also taken into account when interpreting the estimated surface fluxes. In this study, we employ an atmospheric inverse model to investigate the impacts of retrievals biases and temporally varying global distribution of GOSAT XCO2 on surface CO2 flux estimates. Inversions are performed for 2009-2013, with several subsets of the 5-year record of GOSAT XCO2 (v2.21) and its bias-corrected XCO2. GOSAT XCO2 data consist of three types: H-gain for vegetated lands, M-gain for bright surfaces (desert areas), and sun-glint for ocean surface. The results show that the global spatial distributions of estimated CO2 fluxes depend on the subset of XCO2 used. M-gain XCO2 results in unrealistically high CO2 emissions in and around the Middle East, including the neighboring ocean regions. On the other hand, M-gain XCO2 causes compensating unrealistic uptakes far beyond M-gain regions in low latitudes, also partially contributing on the summer uptake in Europe. The joint inversions with both surface measurements and GOSAT XCO2 data obtain larger flux gradient between the northern extra-tropics and the tropics than the inversion with surface measurements only for the first 2 years. Recently, these North-South gradients seem to be gradually reducing as the tropics become a weaker source or turn into a sink, while the net emission strength in East Asia is increasing

Simultaneous assimilation of AIRS and GOSAT CO2 observations with Ensemble Kalman filter

NASA Astrophysics Data System (ADS)

Liu, J.; Kalnay, E.; Fung, I.; Kang, J.

2012-12-01

Lack of CO2 vertical information could lead to bias in the surface CO2 flux estimation (Stephens et al., 2007). Liu et al. (2012) showed that assimilating AIRS CO2 observations, which are sensitive to middle to upper troposphere CO2, improves CO2 concentration, especially in the middle to upper troposphere. GOSAT is sensitive to CO2 over the whole column, but the spatial coverage is sparser than AIRS. In this study, we assimilate AIRS and GOSAT CO2 observations simultaneously along with surface flask CO2 observations and meteorology observations with Ensemble Kalman filter (EnKF) to constrain CO2 vertical profiles simulated by NCAR carbon-climate model. We will show the impact of assimilating AIRS and GOSAT CO2 on the CO2 vertical gradient, seasonal cycle and spatial gradient by assimilating only GOSAT or AIRS and comparing to the control experiment. The quality of CO2 analysis will be examined by validating against independent CO2 aircraft observations, and analyzing the relationship between CO2 analysis fields and major circulation, such as Madden Julian Oscillation. We will also discuss the deficiencies of the observation network in understanding the carbon cycle.

The results of the critical design of the mission instruments of GOSAT-2

NASA Astrophysics Data System (ADS)

Yajima, Yukie; Suto, Hiroshi; Yotsumoto, Kazuhiko; Miyakawa, Takehiro; Hashimoto, Makiko; Shiomi, Kei; Nakajima, Masakatsu; Hirabayashi, Takeshi

2016-04-01

The GOSAT-2 is the successor satellite to the GOSAT which is the satellite dedicated to the measurements of the greenhouse gases such as carbon dioxide and methane. GOSAT was launched in January of 2009 and has been operated for about seven years. The development of the GOSAT-2 has been continued for two years, and through the preliminary and critical design phase the detail of the design of the mission instruments were fixed as well as the bus system design. The mission instruments of the GOSAT-2 are TANSO-FTS-2 and TANSO-CAI-2. TANSO-FTS-2 is the Fourier Transform Spectrometer observing greenhouse gases such as Carbon Dioxide and Methane and TANSO-CAI-2 is the imager observing the aerosols and clouds to compensate the TANSO-FTS-2 data and to grasp the movements of the aerosols such as PM2.5. The mission instruments will adopt the same kinds of instruments as GOSAT. But some improvements will be carried. Based on the results of the preliminary design, the design had been refined in the critical design phase and the results of the design meets all of the requirements on the mission instruments derived from the mission requirements to understand CO2 and CH4 sources and sinks and carbon cycle precisely. To improve the measurement accuracy, the signal to noise ratio will be increased by the extension of the aperture size from 64mm to 73mm and cooling the after optics as well as the thermal detectors. And to increase the number of the useful data, GOSAT-2 will equip the function to avoid the clouds during the observation using the images obtained by the monitor camera in FTS. To observe the carbon monoxide, the 2.3μm observation channel will be added. This function will be realized by the extension of the 2.0μm observation band to 2.3μm. The pointing angle in the along track direction will be extend from 20 degrees of GOSAT to 40 degrees to expand the observation area over the ocean where the sun glint is observed. This will make it possible to increase the number

Preliminary analysis toward GOSAT-2 new products, proxy-based XCH4 and SIF, using GOSAT data

NASA Astrophysics Data System (ADS)

Oshio, H.; Yoshida, Y.; Matsunaga, T.

2017-12-01

The Greenhouse gases Observing SATellite (GOSAT) has been operating for more than eight years. As a successor mission to the GOSAT, GOSAT-2 is planned to be launched in FY2018. In addition to the full-physics based dry air mole fractions of carbon dioxide, methane, water vapor, and carbon monoxide (XCO2, XCH4, XH2O, and XCO) products, we are planning to provide the proxy-based XCH4 and solar induced chlorophyll fluorescence (SIF) as a new product. XCH4 and XCO2 are retrieved from GOSAT CH4 1.67 μm band and CO2 1.6 μm band, respectively, under the clear-sky assumption, and their ratio is compared with TCCON data. As expected, most of the cloud and aerosol related errors are counteracted. During this retrieval, XH2O is simultaneously retrieved with XCO2. XCO2 and XH2O are also retrieved from CO2 2.08 μm band under the clear-sky assumption. Difference between Xgas retrieved from different wavelength domains is expected to be useful as cloud and aerosol information because the difference reflects the degree of optical path variation caused by clouds and aerosols. XCO2 ratio and XH2O ratio are compared to the cloud and aerosol information derived by Cloud and Aerosol Imager (CAI) onboarded GOSAT. SIF is retrieved using Fraunhofer lines near O2 A-band by the same method as Frankenberg et al. (2011). For GOSAT, correction of artifact signal (zero-level offset caused by non-linearity of the analog circuit in the spectrometer) is required to obtain SIF (retrieved signal = SIF + zero-level offset). The zero-level offset can be evaluated from the retrieved signal over the areas where the value of SIF is expected to be zero. Although it is currently unknown that such correction is required for GOSAT-2 SIF retrieval, SIF was retrieved from GOSAT data and zero-level offset correction was tested. We investigated the zero-level offset for clouds and bare soils and confirmed its applicability to the offset correction. Zero-level offset correction was then conducted while

Validation of XCH4 derived from SWIR spectra of GOSAT TANSO-FTS with aircraft measurement data

NASA Astrophysics Data System (ADS)

Inoue, M.; Morino, I.; Uchino, O.; Miyamoto, Y.; Saeki, T.; Yoshida, Y.; Yokota, T.; Sweeney, C.; Tans, P. P.; Biraud, S. C.; Machida, T.; Pittman, J. V.; Kort, E. A.; Tanaka, T.; Kawakami, S.; Sawa, Y.; Tsuboi, K.; Matsueda, H.

2014-09-01

Column-averaged dry-air mole fractions of methane (XCH4), retrieved from Greenhouse gases Observing SATellite (GOSAT) short-wavelength infrared (SWIR) spectra, were validated by using aircraft measurement data from the National Oceanic and Atmospheric Administration (NOAA), the US Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the HIAPER Pole-to-Pole Observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. In the calculation of XCH4 from aircraft measurements (aircraft-based XCH4), other satellite data were used for the CH4 profiles above the tropopause. We proposed a data-screening scheme for aircraft-based XCH4 for reliable validation of GOSAT XCH4. Further, we examined the impact of GOSAT SWIR column averaging kernels (CAK) on the aircraft-based XCH4 calculation and found that the difference between aircraft-based XCH4 with and without the application of the GOSAT CAK was less than ±9 ppb at maximum, with an average difference of -0.5 ppb. We compared GOSAT XCH4 Ver. 02.00 data retrieved within ±2° or ±5° latitude-longitude boxes centered at each aircraft measurement site with aircraft-based XCH4 measured on a GOSAT overpass day. In general, GOSAT XCH4 was in good agreement with aircraft-based XCH4. However, over land, the GOSAT data showed a positive bias of 1.5 ppb (2.0 ppb) with a standard deviation of 14.9 ppb (16.0 ppb) within the ±2° (±5°) boxes, and over ocean, the average bias was 4.1 ppb (6.5 ppb) with a standard deviation of 9.4 ppb (8.8 ppb) within the ±2° (±5°) boxes. In addition, we obtained similar results when we used an aircraft-based XCH4 time series obtained by curve fitting with temporal interpolation for comparison with GOSAT data.

Measuring Atmospheric Carbon Dioxide from Space: The GOSAT and OCO-2 Missions

NASA Technical Reports Server (NTRS)

Crisp, David

2011-01-01

The Japanese Greenhouse gases Observing Satellite (GOSAT) is providing new insight into atmospheric carbon dioxide trends. The NASA Orbiting Carbon Observatory-2 (OCO-2)Mission will build on this record with increased sensitivity resolution, and coverage.

Extraction and Analysis of Regional Emission and Absorption Events of Greenhouse Gases with GOSAT and OCO-2

NASA Astrophysics Data System (ADS)

Kasai, K.; Shiomi, K.; Konno, A.; Tadono, T.; Hori, M.

2016-12-01

Global observation of greenhouse gases such as carbon dioxide (CO2) and methane (CH4) with high spatio-temporal resolution and accurate estimation of sources and sinks are important to understand greenhouse gases dynamics. Greenhouse Gases Observing Satellite (GOSAT) has observed column-averaged dry-air mole fractions of CO2 (XCO2) and CH4 (XCH4) over 7 years since January 2009 with wide swath but sparse pointing. Orbiting Carbon Observatory-2 (OCO-2) has observed XCO2 jointly on orbit since July 2014 with narrow swath but high resolution. We use two retrieved datasets as GOSAT observation data. One is ACOS GOSAT/TANSO-FTS Level 2 Full Product by NASA/JPL, and the other is NIES TANSO-FTS L2 column amount (SWIR). By using these GOSAT datasets and OCO-2 L2 Full Product, the biases among datasets, local sources and sinks, and temporal variability of greenhouse gases are clarified. In addition, CarbonTracker, which is a global model of atmospheric CO2 and CH4 developed by NOAA/ESRL, are also analyzed for comparing between satellite observation data and atmospheric model data. Before analyzing these datasets, outliers are screened by using quality flag, outcome flag, and warn level in land or sea parts. Time series data of XCO2 and XCH4 are obtained globally from satellite observation and atmospheric model datasets, and functions which express typical inter-annual and seasonal variation are fitted to each spatial grid. Consequently, anomalous events of XCO2 and XCH4 are extracted by the difference between each time series dataset and the fitted function. Regional emission and absorption events are analyzed by time series variation of satellite observation data and by comparing with atmospheric model data.

A comparison of OCO-2 XCO2 Observations to GOSAT and Models

NASA Astrophysics Data System (ADS)

O'Dell, C.; Eldering, A.; Crisp, D.; Gunson, M. R.; Fisher, B.; Mandrake, L.; McDuffie, J. L.; Baker, D. F.; Wennberg, P. O.

2016-12-01

With their high spatial resolution and dense sampling density, observations of atmospheric carbon dioxide (CO2) from space-based sensors such as the Orbiting Carbon Observatory-2 (OCO-2) have the potential to revolutionize our understanding of carbon sources and sinks. To achieve this goal, however, requires the observations to have sub-ppm systematic errors; the large data density of OCO-2 generally reduces the importance of random errors in the retrieval of of regional scale fluxes. In this work, the Atmospheric Carbon Observations from Space (ACOS) algorithm has been applied to both OCO-2 and GOSAT observations, which overlap for the period spanning Sept 2014 to present (2+ years). Previous activities utilizing TCCON and aircraft data have shown the ACOS/GOSAT B3.5 product to be quite accurate (1-2 ppm) over both land and ocean. In this work, we apply nearly identical versions of the ACOS retrieval algorithm to both OCO-2 and GOSAT to enable comparisons during the period of overlap, and to minimize algorithm-induced differences. GOSAT/OCO-2 comparisons are used to explore potential biases in the OCO-2 data, and to better understand the nature of the bias correction required for each product. Finally, each product is compared to an ensemble of models in order to evaluate their relative consistency, a critical activity before both can be used simultaneously in carbon flux inversions with confidence.

High-resolution CO2 and CH4 flux inverse modeling combining GOSAT, OCO-2 and ground-based observations

NASA Astrophysics Data System (ADS)

Maksyutov, S. S.; Oda, T.; Saito, M.; Ito, A.; Janardanan Achari, R.; Sasakawa, M.; Machida, T.; Kaiser, J. W.; Belikov, D.; Valsala, V.; O'Dell, C.; Yoshida, Y.; Matsunaga, T.

2017-12-01

We develop a high-resolution CO2 and CH4 flux inversion system that is based on the Lagrangian-Eulerian coupled tracer transport model, and is designed to estimate surface fluxes from atmospheric CO2 and CH4 data observed by the GOSAT and OCO-2 satellites and by global in-situ networks, including observation in Siberia. We use the Lagrangian particle dispersion model (LPDM) FLEXPART to estimate the surface flux footprints for each observation at 0.1-degree spatial resolution for three days of transport. The LPDM is coupled to a global atmospheric tracer transport model (NIES-TM). The adjoint of the coupled transport model is used in an iterative optimization procedure based on either quasi-Newtonian algorithm or singular value decomposition. Combining surface and satellite data for use in inversion requires correcting for biases present in satellite observation data, that is done in a two-step procedure. As a first step, bi-weekly corrections to prior flux fields are estimated for the period of 2009 to 2015 from in-situ CO2 and CH4 data from global observation network, included in Obspack-GVP (for CO2), WDCGG (CH4) and JR-STATION datasets. High-resolution prior fluxes were prepared for anthropogenic emissions (ODIAC and EDGAR), biomass burning (GFAS), and the terrestrial biosphere. The terrestrial biosphere flux was constructed using a vegetation mosaic map and separate simulations of CO2 fluxes by the VISIT model for each vegetation type present in a grid. The prior flux uncertainty for land is scaled proportionally to monthly mean GPP by the MODIS product for CO2 and EDGAR emissions for CH4. Use of the high-resolution transport leads to improved representation of the anthropogenic plumes, often observed at continental continuous observation sites. OCO-2 observations are aggregated to 1 second averages, to match the 0.1 degree resolution of the transport model. Before including satellite observations in the inversion, the monthly varying latitude-dependent bias is

Development of the GOSAT-2 FTS-2 Simulator and Preliminary Sensitivity Analysis for CO2 Retrieval

NASA Astrophysics Data System (ADS)

Kamei, A.; Yoshida, Y.; Dupuy, E.; Hiraki, K.; Yokota, Y.; Oishi, Y.; Murakami, K.; Morino, I.; Matsunaga, T.

2013-12-01

The Greenhouse Gases Observing Satellite-2 (GOSAT-2), which is a successor mission to the GOSAT, is planned to be launched in FY 2017. The Fourier Transform Spectrometer-2 (FTS-2) onboard the GOSAT-2 is a primary sensor to observe infrared light reflected and emitted from the Earth's surface and atmosphere. The FTS-2 obtains high-spectral resolution spectra with four bands from near to short-wavelength infrared (SWIR) region and one band in the thermal infrared (TIR) region. The column amounts of carbon dioxide (CO2) and methane (CH4) are retrieved from the obtained radiance spectra with SWIR bands. Compared to the FTS onboard the GOSAT, the FTS-2 includes an additional SWIR band to allow for carbon monoxide (CO) measurement. We have been developing a tool, named GOSAT-2 FTS-2 simulator, which is capable of simulating the spectral radiance data observed by the FTS-2 using the Pstar2 radiative transfer code. The purpose of the GOSAT-2 FTS-2 simulator is to obtain data which is exploited in the sensor specification, the optimization of parameters for Level 1 processing, and the improvement of Level 2 algorithms. The GOSAT-2 FTS-2 simulator, composed of the six components: 1) Overall control, 2) Onboarding platform, 3) Spectral radiance calculation, 4) Fourier transform, 5) L1B processing, and 6) L1B data output, has been installed on the GOSAT Research Computation Facility (GOSAT RCF), which is a large-scale, high-performance, and energy-efficient computer. We present the progress in the development of the GOSAT-2 FTS-2 simulator and the preliminary sensitivity analysis, relating to the engineering parameters, the aerosols and clouds, and so on, on the Level 1 processing for CO2 retrieval from the obtained data by simulating the FTS-2 SWIR observation using the GOSAT-2 FTS-2 simulator.

Potential Applications of Gosat Based Carbon Budget Products to Refine Terrestrial Ecosystem Model

NASA Astrophysics Data System (ADS)

Kondo, M.; Ichii, K.

2011-12-01

Estimation of carbon exchange in terrestrial ecosystem associates with difficulties due to complex entanglement of physical and biological processes: thus, the net ecosystem productivity (NEP) estimated from simulation often differs among process-based terrestrial ecosystem models. In addition to complexity of the system, validation can only be conducted in a point scale since reliable observation is only available from ground observations. With a lack of large spatial data, extension of model simulation to a global scale results in significant uncertainty in the future carbon balance and climate change. Greenhouse gases Observing SATellite (GOSAT), launched by the Japanese space agency (JAXA) in January, 2009, is the 1st operational satellite promised to deliver the net land-atmosphere carbon budget to the terrestrial biosphere research community. Using that information, the model reproducibility of carbon budget is expected to improve: hence, gives a better estimation of the future climate change. This initial analysis is to seek and evaluate the potential applications of GOSAT observation toward the sophistication of terrestrial ecosystem model. The present study was conducted in two processes: site-based analysis using eddy covariance observation data to assess the potential use of terrestrial carbon fluxes (GPP, RE, and NEP) to refine the model, and extension of the point scale analysis to spatial using Carbon Tracker product as a prototype of GOSAT product. In the first phase of the experiment, it was verified that an optimization routine adapted to a terrestrial model, Biome-BGC, yielded the improved result with respect to eddy covariance observation data from AsiaFlux Network. Spatial data sets used in the second phase were consists of GPP from empirical algorithm (e.g. support vector machine), NEP from Carbon Tracker, and RE from the combination of these. These spatial carbon flux estimations was used to refine the model applying the exactly same

Consistent Evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC Through Comparisons to TCCON

NASA Technical Reports Server (NTRS)

Kulawik, Susan; Wunch, Debra; O’Dell, Christopher; Frankenberg, Christian; Reuter, Maximilian; Chevallier, Frederic; Oda, Tomohiro; Sherlock, Vanessa; Buchwitz, Michael; Osterman, Greg;

One-year operation of TANSO-FTS on GOSAT and follow-on mission feasibility

NASA Astrophysics Data System (ADS)

Shiomi, Kei; Nakajima, Masakatsu; Kuze, Akihiko; Takeshima, Toshiaki; Kawakami, Shuji; Suto, Hiroshi

2017-11-01

The Greenhouse gases Observing SATellite (GOSAT) was developed to contribute to monitoring of carbon dioxide and methane from space [1]. The mission objectives are global greenhouse gas measurements from space with precision of 1 % for CO2 and 2 % for CH4 in seasonal mean. The GOSAT carries Thermal And Near infrared Sensor for carbon Observation (TANSO) for precise measurement of greenhouse gases. Main instrument is Fourier Transfer Spectrometer (TANSO-FTS) to observe atmospheric absorption spectra of CO2 and CH4 with high spectral resolution of 0.2 cm-1, broad wavelength coverage of 0.76 - 14.3 microns, wide swath of 790 km and frequent revisit of 3 days. Cloud and Aerosol Imager (TANSO-CAI) is simultaneously on board for cloud detection and correction of optical thin cirrus and aerosol interference within the FTS instantaneous field of view. The GOSAT satellite was launched by H2A-15 rocket on January 23, 2009. The Level 1B products of calibrated spectra were released from September 2009 in public. The Level 2 products of CO2 and CH4 column densities were released from February 2010 [2]. The normal observation data is acquired over one year regularly from April 2009. The mission lifetime is 5 years.

A spatio-temporal analysis for regional enhancements of greenhouse gas concentration with GOSAT and OCO-2

NASA Astrophysics Data System (ADS)

Kasai, K.; Shiomi, K.; Konno, A.; Tadono, T.; Hori, M.

2017-12-01

Global observation of greenhouse gases such as carbon dioxide (CO2) and methane (CH4) with high spatio-temporal resolution and accurate estimation of sources and sinks are important to understand greenhouse gases dynamics. Greenhouse Gases Observing Satellite (GOSAT) has observed column-averaged dry-air mole fractions of CO2 (XCO2) and CH4 (XCH4) over 8 years since January 2009 with 3-day repeat cycle. Orbiting Carbon Observatory-2 (OCO-2) has observed XCO2 on orbit since July 2014 with 16-day repeat cycle. The objective of this study investigates regional enhancements of greenhouse gases concentrations using GOSAT and OCO-2 data. We use two retrieved datasets as GOSAT observation data. One is ACOS GOSAT/TANSO-FTS Level 2 Standard Product B7.3 by NASA/JPL, and the other is NIES TANSO-FTS SWIR L2 Product V02. As OCO-2 observation data, OCO-2 Operational L2 Data Version 7 is used. ODIAC dataset is also used for classification of regional enhancements into anthropogenic and biogenic sources. Before analyzing these datasets, outliers are screened by using "quality flag", "outcome flag" and "warn level" in land or water parts, and the "M-gain" data observed by GOSAT are removed. Then, the monthly mean XCO2 and XCH4 of all greenhouse gases datasets is calculated from the daily mean XCO2 and XCH4 to correct the weight by the difference in the number of observation points. Biases among datasets are assessed by comparing the monthly mean XCO2 and XCH4. Also, anomalies of XCO2 and XCH4 are computed by subtracting the monthly mean from individual observations. The positive and negative anomalies are candidates for regional enhancements and uptake, respectively. To detect the regional enhancements from the satellite observation datasets, the results of spatio-temporal analysis of the anomalies are also reported.

Reduced carbon uptake during the 2010 Northern Hemisphere summer from GOSAT

NASA Astrophysics Data System (ADS)

Guerlet, S.; Basu, S.; Butz, A.; Krol, M.; Hahne, P.; Houweling, S.; Hasekamp, O. P.; Aben, I.

2013-05-01

Column-averaged dry air mole fractions of carbon dioxide (XCO2) measured by the Greenhouse Gases Observing Satellite (GOSAT) reveal significant interannual variation (IAV) of CO2uptake during the Northern Hemisphere summer between 2009 and 2010. The XCO2drawdown in 2010 is shallower than in 2009 by 2.4 ppm and 3.0 ppm over North America and Eurasia, respectively. Reduced carbon uptake in the summer of 2010 is most likely due to the heat wave in Eurasia driving biospheric fluxes and fire emissions. A joint inversion of GOSAT and surface data estimates an integrated biospheric and fire emission anomaly in April-September of 0.89 ±0.20 PgC over Eurasia. In contrast, inversions of surface measurements alone fail to replicate the observed XCO2IAV and underestimate emission IAV over Eurasia. This shows the value of GOSAT XCO2in constraining the response of land-atmosphere exchange of CO2 to climate events.

Consistent evaluation of GOSAT, SCIAMACHY, carbontracker, and MACC through comparisons to TCCON

DOE PAGES

Kulawik, S. S.; Wunch, D.; O'Dell, C.; ...

2015-06-22

Consistent validation of satellite CO 2 estimates is a prerequisite for using multiple satellite CO 2 measurements for joint flux inversion, and for establishing an accurate long-term atmospheric CO 2 data record. We focus on validating model and satellite observation attributes that impact flux estimates and CO 2 assimilation, including accurate error estimates, correlated and random errors, overall biases, biases by season and latitude, the impact of coincidence criteria, validation of seasonal cycle phase and amplitude, yearly growth, and daily variability. We evaluate dry air mole fraction (X CO 2) for GOSAT (ACOS b3.5) and SCIAMACHY (BESD v2.00.08) as wellmore » as the CarbonTracker (CT2013b) simulated CO 2 mole fraction fields and the MACC CO 2 inversion system (v13.1) and compare these to TCCON observations (GGG2014). We find standard deviations of 0.9 ppm, 0.9, 1.7, and 2.1 ppm versus TCCON for CT2013b, MACC, GOSAT, and SCIAMACHY, respectively, with the single target errors 1.9 and 0.9 times the predicted errors for GOSAT and SCIAMACHY, respectively. When satellite data are averaged and interpreted according to error 2 = a 2+ b 2 / n (where n are the number of observations averaged, a are the systematic (correlated) errors, and b are the random (uncorrelated) errors), we find that the correlated error term a = 0.6 ppm and the uncorrelated error term b = 1.7 ppm for GOSAT and a = 1.0 ppm, b = 1.4 ppm for SCIAMACHY regional averages. Biases at individual stations have year-to-year variability of ~ 0.3 ppm, with biases larger than the TCCON predicted bias uncertainty of 0.4 ppm at many stations. Using fitting software, we find that GOSAT underpredicts the seasonal cycle amplitude in the Northern Hemisphere (NH) between 46–53° N. In the Southern Hemisphere (SH), CT2013b underestimates the seasonal cycle amplitude. Biases are calculated for 3-month intervals and indicate the months that contribute to the observed amplitude differences. The seasonal cycle

Dependence on Solar Phase Angle and Grain Size of the Spectral Reflectance of the Railroad Valley Playa for GOSAT/GOSAT-2 Vicarious Calibration

NASA Astrophysics Data System (ADS)

Arai, T.; Matsunaga, T.

2017-12-01

GOSAT and the next generation GOSAT-2 satellites estimate the concentration of greenhouse gasses, and distribution of aerosol and cloud to observe solar light reflection and radiation from surface and atmosphere of the Earth. Precise information of the surface and the bidirectional reflectance distribution function (BRDF) are required for the estimation because the surface reflectance of solar light varies with the observation geometry and the surface condition. The purpose of this study is to search an appropriate BRDF model of the GOSAT calibration site (Railroad Valley playa). In 2017, JAXA, NIES, and NASA/OCO-2 teams collaboratively performed 9th vicarious experiments by the simultaneous observation with GOSAT, OCO-2, and ground-based equipment (Kuze et al., 2014) at the Railroad Valley from June 25 to 30. We performed the BRDF measurement to observe solar light reflection by varying with observed angles using a spectroradiometer (FieldSpec4, ASD Inc.) mounted on a one-axis goniometer. The surface sand was shifted to several sizes of grain (75, 125, 250, 500, and 1000 μm), which was measured for the limited area of 5mm diameter with a collimating lens (74-UV, OceanOptics). The BRDF parameters for the observed reflectance were determined by the least squares fitting with the free parameters of a single scattering albedo and an asymmetric factor (Hapke, 2012) for the ultraviolet to near infrared wavelength bands of GOSAT. The resulting value of the single scattering albedo increased with decreasing the grain size of the sands. The observed reflectance of the fine grain sands (below 250 μm) is not varied with observed phase angles (solar incident light - surface sand - detector) as a Lambertian reflectance, but the spectra of coarse grain sands (above 500 μm) are varied with the observation angles. Therefore, a priori information of the target surface such as grain size is required for the determination of the precise reflectance of the target.

GOSAT validation out standing in the field: A case study of satellite validation using the SSEC Portable Atmospheric Research Center (SPARC)

NASA Astrophysics Data System (ADS)

Wagner, T. J.; Borg, L. A.; Feltz, M.; Gero, P. J.; Knuteson, R. O.; Olson, E.

2016-12-01

The Space Science and Engineering Center (SSEC) at the University of Wisconsin-Madison has developed the SSEC Portable Atmospheric Research Center (SPARC), a mobile 11 m trailer that houses numerous in situ and ground-based remote sensing instruments. Available instrumentation includes the Atmospheric Emitted Radiance Interferometer (AERI), a hyperspectral infrared radiometer from which trace gas concentrations and profiles of temperature and water vapor can be retrieved; the High Spectral Resolution Lidar (HSRL), a multichannel lidar capable of directly retrieving profiles of optical depth and backscatter depolarization; and a Doppler lidar wind profiler. The remote instrumentation suite is complemented by surface meteorology observations and a radiosonde ground station. Collectively, these instruments enable SPARC to participate in a wide variety of field studies, including meteorological field experiments and ground-based satellite calibration and validation studies. In August 2016, SPARC traveled to the Chequamegon National Forest in northern Wisconsin for a two week long deployment alongside the WLEF-TV tower. This 447 m tower houses long-term observations of thermodynamic and atmospheric composition at multiple heights, enabling studies of phenomena like atmospheric/land surface interactions and carbon uptake. During this deployment, SPARC launched radiosondes coincident with clear-sky overpasses of the Greenhouse gases Observing SATellite (GOSAT). Thermodynamic profiles from the radiosondes and AERI combined with the trace gas observations from the tower were used to validate the GOSAT observations of carbon dioxide and methane. The on-site presence of SPARC allowed for better characterization of the environment and greater observational certainty than was possible with the tower alone. Examples from this particular validation study as well as a discussion of how SPARC can contribute to other satellite calibration and validation investigations will be

Bias corrections of GOSAT SWIR XCO2 and XCH4 with TCCON data and their evaluation using aircraft measurement data

NASA Astrophysics Data System (ADS)

Inoue, Makoto; Morino, Isamu; Uchino, Osamu; Nakatsuru, Takahiro; Yoshida, Yukio; Yokota, Tatsuya; Wunch, Debra; Wennberg, Paul O.; Roehl, Coleen M.; Griffith, David W. T.; Velazco, Voltaire A.; Deutscher, Nicholas M.; Warneke, Thorsten; Notholt, Justus; Robinson, John; Sherlock, Vanessa; Hase, Frank; Blumenstock, Thomas; Rettinger, Markus; Sussmann, Ralf; Kyrö, Esko; Kivi, Rigel; Shiomi, Kei; Kawakami, Shuji; De Mazière, Martine; Arnold, Sabrina G.; Feist, Dietrich G.; Barrow, Erica A.; Barney, James; Dubey, Manvendra; Schneider, Matthias; Iraci, Laura T.; Podolske, James R.; Hillyard, Patrick W.; Machida, Toshinobu; Sawa, Yousuke; Tsuboi, Kazuhiro; Matsueda, Hidekazu; Sweeney, Colm; Tans, Pieter P.; Andrews, Arlyn E.; Biraud, Sebastien C.; Fukuyama, Yukio; Pittman, Jasna V.; Kort, Eric A.; Tanaka, Tomoaki

2016-08-01

We describe a method for removing systematic biases of column-averaged dry air mole fractions of CO2 (XCO2) and CH4 (XCH4) derived from short-wavelength infrared (SWIR) spectra of the Greenhouse gases Observing SATellite (GOSAT). We conduct correlation analyses between the GOSAT biases and simultaneously retrieved auxiliary parameters. We use these correlations to bias correct the GOSAT data, removing these spurious correlations. Data from the Total Carbon Column Observing Network (TCCON) were used as reference values for this regression analysis. To evaluate the effectiveness of this correction method, the uncorrected/corrected GOSAT data were compared to independent XCO2 and XCH4 data derived from aircraft measurements taken for the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, the National Oceanic and Atmospheric Administration (NOAA), the US Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the Japan Meteorological Agency (JMA), the HIAPER Pole-to-Pole observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. These comparisons demonstrate that the empirically derived bias correction improves the agreement between GOSAT XCO2/XCH4 and the aircraft data. Finally, we present spatial distributions and temporal variations of the derived GOSAT biases.

Bias corrections of GOSAT SWIR XCO 2 and XCH 4 with TCCON data and their evaluation using aircraft measurement data

DOE PAGES

Inoue, Makoto; Morino, Isamu; Uchino, Osamu; ...

2016-08-01

We describe a method for removing systematic biases of column-averaged dry air mole fractions of CO 2 (XCO 2) and CH 4 (XCH 4) derived from short-wavelength infrared (SWIR) spectra of the Greenhouse gases Observing SATellite (GOSAT). We conduct correlation analyses between the GOSAT biases and simultaneously retrieved auxiliary parameters. We use these correlations to bias correct the GOSAT data, removing these spurious correlations. Data from the Total Carbon Column Observing Network (TCCON) were used as reference values for this regression analysis. To evaluate the effectiveness of this correction method, the uncorrected/corrected GOSAT data were compared to independent XCO 2more » and XCH 4 data derived from aircraft measurements taken for the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, the National Oceanic and Atmospheric Administration (NOAA), the US Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the Japan Meteorological Agency (JMA), the HIAPER Pole-to-Pole observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. These comparisons demonstrate that the empirically derived bias correction improves the agreement between GOSAT XCO 2/XCH 4 and the aircraft data. Finally, we present spatial distributions and temporal variations of the derived GOSAT biases.« less

Bias corrections of GOSAT SWIR XCO 2 and XCH 4 with TCCON data and their evaluation using aircraft measurement data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inoue, Makoto; Morino, Isamu; Uchino, Osamu

We describe a method for removing systematic biases of column-averaged dry air mole fractions of CO 2 (XCO 2) and CH 4 (XCH 4) derived from short-wavelength infrared (SWIR) spectra of the Greenhouse gases Observing SATellite (GOSAT). We conduct correlation analyses between the GOSAT biases and simultaneously retrieved auxiliary parameters. We use these correlations to bias correct the GOSAT data, removing these spurious correlations. Data from the Total Carbon Column Observing Network (TCCON) were used as reference values for this regression analysis. To evaluate the effectiveness of this correction method, the uncorrected/corrected GOSAT data were compared to independent XCO 2more » and XCH 4 data derived from aircraft measurements taken for the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, the National Oceanic and Atmospheric Administration (NOAA), the US Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the Japan Meteorological Agency (JMA), the HIAPER Pole-to-Pole observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. These comparisons demonstrate that the empirically derived bias correction improves the agreement between GOSAT XCO 2/XCH 4 and the aircraft data. Finally, we present spatial distributions and temporal variations of the derived GOSAT biases.« less

Validation of XCO2 derived from SWIR spectra of GOSAT TANSO-FTS with aircraft measurement data

NASA Astrophysics Data System (ADS)

Inoue, M.; Morino, I.; Uchino, O.; Miyamoto, Y.; Yoshida, Y.; Yokota, T.; Machida, T.; Sawa, Y.; Matsueda, H.; Sweeney, C.; Tans, P. P.; Andrews, A. E.; Biraud, S. C.; Tanaka, T.; Kawakami, S.; Patra, P. K.

2013-10-01

Column-averaged dry air mole fractions of carbon dioxide (XCO2) retrieved from Greenhouse gases Observing SATellite (GOSAT) Short-Wavelength InfraRed (SWIR) observations were validated with aircraft measurements by the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, the National Oceanic and Atmospheric Administration (NOAA), the US Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the HIAPER Pole-to-Pole Observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. To calculate XCO2 based on aircraft measurements (aircraft-based XCO2), tower measurements and model outputs were used for additional information near the surface and above the tropopause, respectively. Before validation, we investigated the impacts of GOSAT SWIR column averaging kernels (CAKs) and the shape of a priori profiles on the aircraft-based XCO2 calculation. The differences between aircraft-based XCO2 with and without the application of GOSAT CAK were evaluated to be less than ±0.4 ppm at most, and less than ±0.1 ppm on average. Therefore, we concluded that the GOSAT CAK produces only a minor effect on the aircraft-based XCO2 calculation in terms of the overall uncertainty of GOSAT XCO2. We compared GOSAT data retrieved within ±2 or ±5° latitude/longitude boxes centered at each aircraft measurement site to aircraft-based data measured on a GOSAT overpass day. The results indicated that GOSAT XCO2 over land regions agreed with aircraft-based XCO2, except that the former is biased by -0.68 ppm (-0.99 ppm) with a standard deviation of 2.56 ppm (2.51 ppm), whereas the averages of the differences between the GOSAT XCO2 over ocean and the aircraft-based XCO2 were -1.82 ppm (-2.27 ppm) with a standard deviation of 1.04 ppm (1.79 ppm) for ±2° (±5°) boxes.

The study of the mission instruments of GOSAT-2

NASA Astrophysics Data System (ADS)

Suto, H.; Nakajima, M.; Kuze, A.; Shiomi, K.; Shimoda, H.

2012-12-01

Greenhouse Gases Observing Satellite "GOSAT" was launched in January of 2009 and have observed the carbon dioxide and the methane almost four years. Additionally, the Level 1B algorithm has been improved based on the on board calibration and ground test using Engineering model and the accuracy of the level 1B data, that is the spectrum, has been improved. This has led to the more accurate calculation of the concentration of carbon dioxide and methane with small bias. At the same time, some issues have become clearer little by little through the on orbit operation. Especially a lot of data have been affected by the cloud, so few data have been used until now. However, the satellite has come to be recognized as an effective means of the detection of the global distribution of the greenhouse gases concentration. And in addition to the effort to resolve the issues which have become clear until now, the improvement of the observation performance have been required by a lot of users. Therefore, we researched the concrete requirements of users and set the mission requirements for GOSAT-2. Based on this mission requirement, we have studied the possibilities of these requirements. This study was implemented as premises for the usage of the Fourier Transform Spectrometer to detect the greenhouse gases as well as GOSAT. We considered the methods to increase the number of the useful data. For example, the reduction of the footprints size, increase of the number of the IFOV, the intelligent pointing and so on. It's necessary to maintain the Signal to Noise ration of the GOSAT. In addition to the method to increase the number of the useful data, we have researched the size of the aperture of the optics to maintain the signal to noise ratio corresponding to the reduction of the footprint seize. But the possibility of the corner cube used in the Fourier transform spectrometer limits the aperture size. We decided the aperture size (and corner cube size) based on the trade-off among

Estimation of regional surface CO2 fluxes with GOSAT observations using two inverse modeling approaches

NASA Astrophysics Data System (ADS)

Maksyutov, Shamil; Takagi, Hiroshi; Belikov, Dmitry A.; Saeki, Tazu; Zhuravlev, Ruslan; Ganshin, Alexander; Lukyanov, Alexander; Yoshida, Yukio; Oshchepkov, Sergey; Bril, Andrey; Saito, Makoto; Oda, Tomohiro; Valsala, Vinu K.; Saito, Ryu; Andres, Robert J.; Conway, Thomas; Tans, Pieter; Yokota, Tatsuya

2012-11-01

Inverse estimation of surface C02 fluxes is performed with atmospheric transport model using ground-based and GOSAT observations. The NIES-retrieved C02 column mixing (Xc02) and column averaging kernel are provided by GOSAT Level 2 product v. 2.0 and PPDF-DOAS method. Monthly mean C02 fluxes for 64 regions are estimated together with a global mean offset between GOSAT data and ground-based data. We used the fixed-lag Kalman filter to infer monthly fluxes for 42 sub-continental terrestrial regions and 22 oceanic basins. We estimate fluxes and compare results obtained by two inverse modeling approaches. In basic approach adopted in GOSAT Level4 product v. 2.01, we use aggregation of the GOSAT observations into monthly mean over 5x5 degree grids, fluxes are estimated independently for each region, and NIES atmospheric transport model is used for forward simulation. In the alternative method, the model-observation misfit is estimated for each observation separately and fluxes are spatially correlated using EOF analysis of the simulated flux variability similar to geostatistical approach, while transport simulation is enhanced by coupling with a Lagrangian transport model Flexpart. Both methods use using the same set of prior fluxes and region maps. Daily net ecosystem exchange (NEE) is predicted by the Vegetation Integrative Simulator for Trace gases (VISIT) optimized to match seasonal cycle of the atmospheric C02 . Monthly ocean-atmosphere C02 fluxes are produced with an ocean pC02 data assimilation system. Biomass burning fluxes were provided by the Global Fire Emissions Database (GFED); and monthly fossil fuel C02 emissions are estimated with ODIAC inventory. The results of analyzing one year of the GOSAT data suggest that when both GOSAT and ground-based data are used together, fluxes in tropical and other remote regions with lower associated uncertainties are obtained than in the analysis using only ground-based data. With version 2.0 of L2 Xc02 the fluxes appear

Comparison of atmospheric CH4 concentration observed by GOSAT and in-situ measurements in Thailand and India

NASA Astrophysics Data System (ADS)

Hayashida, S.; Ono, A.; Ishikawa, S.; Terao, Y.; Takeuchi, W.

2012-12-01

The concentration of atmospheric methane (CH4) has more than doubled since pre-industrial levels and the observed long-term changes in the CH4 concentration have been attributed to anthropogenic activity. However, despite the importance of atmospheric CH4 in global warming, the strength of individual sources of CH4 remains highly uncertain [e.g.,Dlugokencky et al., 2011]. To characterize and quantify the emissions of CH4 especially in Monsoon Asia and Siberia, which are the most important regions as CH4 source, we started a new project, "Characterization and Quantification of global methane emissions by utilizing GOSAT and in-situ measurements " by support of the Environment Research and Technology Development Fund (ERTDF) from June 2012 under the umbrella of Ministry of Environment Japan. The projects includes (1) satellite data applications, (2) in-situ measurements in Siberia, over Western Pacific and in Monsoon Asia, (3) development of the inverse model to derive CH4 emissions by top-down approach, and (4) flux measurements in Siberia and Asia to improve the bottom-up inventories. As an initiatory approach in the project, we started air sampling in Thailand and India where there are only a few CH4 data of direct sampling with high precision. We took eight air samples at Kohn Kaen and Pimai in Thailand on June 9 and 10, 2012. The high CH4 concentration near rice paddy field contrasted to the lower CH4 concentration near Cassava field. We are planning to take more samples in India in mid-August. The satellite CH4 data including GOSAT and SCIAMACHY are also compared with the Land Surface Water Coverage (LSWC) and the Normalized Difference Vegetation Index (NDVI). The analysis revealed the seasonal variation in of xCH4 is closely related to the variation of the LSWC, coupled with NDVI. However, the satellite measurements are all column-averaged mixing ratio (xCH4), and therefore do not necessarily reflect high CH4 concentration near the surface over the emission

Investigation variation of carbon dioxide based on GOSAT data in peninsular Malaysia

NASA Astrophysics Data System (ADS)

Sim, C. K.; Lim, H. S.; MatJafri, M. Z.

2015-10-01

Carbon dioxide (CO2) is an inodorous and transparent gas, and naturally originates in our atmosphere. Due to its optical characteristics, CO2 is the most important greenhouse gas and play a key role in climate change due to an effective thermal infrared (IR) radiation absorber. Satellite observations of atmospheric carbon dioxide (CO2) can significantly improve our knowledge about the sources and sinks of CO2. The remote sensing satellite, namely Greenhouse Gases Observing Satellite (GOSAT) was employed to investigate the spatial and variations of CO2 column-averaged dry airmole fractions, denoted XCO2 over Peninsular Malaysia from January 2013 to December 2013. The analysis of CO2 in the study area shows the significant differences between northeast monsoon (NEM) and the southwest monsoon (SWM). During NEM season, cold air outbreaks from Siberia spreads to equatorial region in the form of north-easterly cold surge winds and associated with a low-level anticyclone over Southeast Asia. Inversely, air masses from the southwest contribute to long-range air pollution due to transportation of atmospheric CO2 by wind is associated with biomass burning in Sumatra, Indonesia. The GOSAT data and the Satellite measurements are able to measure the increase of the atmosphere CO2 values over different regions.

High Resolution CO2 Simulation for Detecting Emission Hotspots Signal in GOSAT XCO2 Data

NASA Astrophysics Data System (ADS)

Janardanan Achari, R.; Kaiser, J. W.; Maksyutov, S. S.; Ito, A.; Ganshin, A.; Zhuravlev, R.; Yoshida, Y.

2014-12-01

Emissions due to combustion of fossil fuel and biomass are two major sources of atmospheric carbon dioxide. The trace gases emitted by biomass burning have a significant influence on the atmosphere which currently accounts for ~25% of the annual anthropogenic emission of CO2into the atmosphere. Also some of the world's most carbon-dense ecosystems like South America and Africa are increasingly susceptible to fire. Though observing atmospheric greenhouse gas dry air mole fractions from space is an approach in practice, the problem of delineating the contribution from the flux arising from different sources has always been a matter of interest. Here we demonstrate the capability of a space-borne CO2 observational platform (Greenhouse gas Observing SATellite, GOSAT) to detect emissions of CO2 due to biomass burning. We made an attempt to detect fire emission signal of CO2 in GOSAT observed total column dry air mole fractions of CO2 (XCO2) for a period June 2009 through December 2012. We performed Lagrangian time inverted simulation (trajectory between 2-3 days) of CO2 transport using FLEXPART for GOSAT observation locations using high resolution (0.1 degree) biomass burning (GFAS V1.1) fluxes. The resulting total column mixing ratios of CO2 (ΔXCO2,model) were grouped into 0.2 ppm bins over spatial regions of 10x10 degree. The result was compared to anomalies of GOSAT XCO2, calculated as ΔXCO2,obs=XCO2,obs-local background (omitting influence from other regimes of emission), collectively for the analysis period and for large continental regions where these detected signals predominate. GOSAT data showed good agreement with modeled ΔXCO2 till about 0.9 ppm (for example regression slope of 0.989 for African continent up to 0.7 ppm) , beyond this, the number of observations with higher ΔXCO2drops and hence poor correspondence to model values. Our analysis points towards the potential of dedicated greenhouse gas observing satellites providing larger number observations

Filling-in of Near-infrared Solar Lines by Terrestrial Fluorescence and Other Geophysical Effects: Simulations and Space-based Observations from SCIAMACHY and GOSAT

NASA Technical Reports Server (NTRS)

Joiner, Joanna (Editor); Yoshida, Yasuko; Vasilkov, A. P.; Middleton, E. M. (Editor); Campbell, P. K. E.; Yoshida, Y.; Huze, A.; Corp, L. A.

2012-01-01

Global mapping of terrestrial vegetation fluorescence from space has recently been accomplished with high spectral resolution (nu/nu greater than 35 000) measurements from the Japanese Greenhouse gases Observing SAellite (GOSAT). These data are of interest because they can potentially provide global information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling. Quantifying the impact of fluorescence on the O2-A band is important as this band is used for photon pathlength characterization in cloud- and aerosol-contaminated pixels for trace-gas retrievals including CO2. Here, we examine whether fluorescence information can be derived from space using potentially lower-cost hyperspectral instrumentation, i.e., more than an order of magnitude less spectral resolution (nu/nu approximately 1600) than GOSAT, with a relatively simple algorithm. We discuss laboratory measurements of fluorescence near one of the few wide and deep solar Fraunhofer lines in the long-wave tail of the fluorescence emission region, the calcium (Ca) II line at 866 nm that is observable with a spectral resolution of approximately 0.5 nm. The filling-in of the Ca II line due to additive signals from various atmospheric and terrestrial effects, including fluorescence, is simulated. We then examine filling-in of this line using the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) satellite instrument. In order to interpret the satellite measurements, we developed a general approach to correct for various instrumental artifacts that produce false filling-in of solar lines in satellite measurements. The approach is applied to SCIAMACHY at the 866 nm Ca II line and to GOSAT at 758 and 770 nm on the shoulders of the O2-A feature where there are several strong solar Fraunhofer lines that are filled in primarily by vegetation fluorescence. Finally, we compare temporal and

Improvement of web-based data acquisition and management system for GOSAT validation lidar data analysis

NASA Astrophysics Data System (ADS)

Okumura, Hiroshi; Takubo, Shoichiro; Kawasaki, Takeru; Abdullah, Indra Nugraha; Uchino, Osamu; Morino, Isamu; Yokota, Tatsuya; Nagai, Tomohiro; Sakai, Tetsu; Maki, Takashi; Arai, Kohei

2013-01-01

A web-base data acquisition and management system for GOSAT (Greenhouse gases Observation SATellite) validation lidar data-analysis has been developed. The system consists of data acquisition sub-system (DAS) and data management sub-system (DMS). DAS written in Perl language acquires AMeDAS (Automated Meteorological Data Acquisition System) ground-level local meteorological data, GPS Radiosonde upper-air meteorological data, ground-level oxidant data, skyradiometer data, skyview camera images, meteorological satellite IR image data and GOSAT validation lidar data. DMS written in PHP language demonstrates satellite-pass date and all acquired data. In this article, we briefly describe some improvement for higher performance and higher data usability. GPS Radiosonde upper-air meteorological data and U.S. standard atmospheric model in DAS automatically calculate molecule number density profiles. Predicted ozone density prole images above Saga city are also calculated by using Meteorological Research Institute (MRI) chemistry-climate model version 2 for comparison to actual ozone DIAL data.

Philippines TCCON Project: Installation, Operation, and Comparisons with GOSAT and OCO-2 Data

NASA Astrophysics Data System (ADS)

Morino, I.; Velazco, V. A.; Hori, A.; Uchino, O.; Sakai, T.; Izumi, T.; Nagai, T.; Bagtasa, G.; Yoshida, Y.; Kiel, M.; Bukosa, B.; Deutscher, N. M.; Fisher, J. A.; Griffith, D. W. T.

2017-12-01

TCCON is dedicated to the precise measurements of greenhouse gases (GHGs) such as CO2 and CH4. TCCON measurements have been and are currently used extensively and globally for satellite validation, for comparison with atmospheric chemistry models and to study atmosphere-biosphere exchanges of carbon. With the global effort to cap GHG emissions, TCCON has taken on a vital role in validating satellite-based GHG data from past, current and future missions like Japanese GOSAT and GOSAT-2, NASA's OCO-2 and OCO-3, Chinese TanSat, TROPOMI, and others. The lack of reliable validation data for the satellite-based GHG observing missions in the tropical regions is a common limitation in global carbon-cycle modeling studies that have a tropical component. The international CO2 modeling community has specified a requirement for "expansion of the CO2 observation network within the tropics" to reduce uncertainties in regional estimates of CO2sources and sinks using atmospheric transport models. To address this challenge, we installed a newly-constructed TCCON FTS at a wind farm operated by the Energy Development Corporation in Burgos, Ilocos Norte, Philippines (18.5326° N, 120.6496° E), which followed rigorous site assessments and discussions at several TCCON and GOSAT-2 science team meetings. After developing the TCCON instrument and characterizing its performance at the NIES in Japan, we deployed the TCCON FTS at the Burgos site in Dec. 2016. Installation and set up of the instruments were concluded in Mar. 2017, followed by first measurements of solar absorption spectra and continued operations in the Philippines using TCCON protocols. Here, we will show obvious CO2, CH4and CO enhancements were observed in Mar. 2017, accompanied by clear depolarization signals from a LIDAR instrument. These enhancements are probably caused by outflow of pollution from major cities in China but the emissions are underestimated in the GEOS-Chem model. Comparisons with GOSAT and OCO-2 soundings

Performance Verification of GOSAT-2 FTS-2 Simulator and Sensitivity Analysis for Greenhouse Gases Retrieval

NASA Astrophysics Data System (ADS)

Kamei, A.; Yoshida, Y.; Dupuy, E.; Hiraki, K.; Matsunaga, T.

2015-12-01

The GOSAT-2, which is scheduled for launch in early 2018, is the successor mission to the Greenhouse gases Observing Satellite (GOSAT). The FTS-2 onboard the GOSAT-2 is a Fourier transform spectrometer, which has three bands in the near to short-wavelength infrared (SWIR) region and two bands in the thermal infrared (TIR) region to observe infrared light reflected and emitted from the Earth's surface and atmosphere with high-resolution spectra. Column amounts and vertical profiles of major greenhouse gases such as carbon dioxide (CO2) and methane (CH4) are retrieved from acquired radiance spectra. In addition, the FTS-2 has several improvements from the FTS onboard the GOSAT: 1) added spectral coverage in the SWIR region for carbon monoxide (CO) retrieval, 2) increased signal-to-noise ratio (SNR) for all bands, 3) extended range of along-track pointing angles for sunglint observations, 4) intelligent pointing to avoid cloud contamination. Since 2012, we have been developing a software tool, which is called the GOSAT-2 FTS-2 simulator, to simulate spectral radiance data that will be acquired by the GOSAT-2 FTS-2. The objective of it is to analyze/optimize data with respect to the sensor specification, the parameters for Level 1 processing, and the improvement of Level 2 retrieval algorithms. It consists of six components: 1) overall control, 2) sensor carrying platform, 3) spectral radiance calculation, 4) Fourier transform module, 5) Level 1B (L1B) processing, and 6) L1B data output. More realistic and faster simulations have been made possible by the improvement of details about sensor characteristics, the sophistication of data processing and algorithms, the addition of various observation modes, the use of surface and atmospheric ancillary data, and the speed-up and parallelization of radiative transfer code. This simulator is confirmed to be working properly from the reproduction of GOSAT FTS L1B data depends on the ancillary data. We will summarize the

CO2 emissions from the 2010 Russian wildfires using GOSAT data.

PubMed

Guo, Meng; Li, Jing; Xu, Jiawei; Wang, Xiufeng; He, Hongshi; Wu, Li

2017-07-01

In the summer of 2010, more than 6 hundred wildfires broke out in western Russia because of an unprecedented intense heat wave that resulted from strong atmospheric blocking. The present study evaluated the CO 2 emissions using GOSAT (Greenhouse gases Observing SATellite) data from July 23 to August 18, 2010 for western Russia. The results demonstrated that the GOSAT CAI (Cloud and Aerosol Imager) was well-suited for the identification of smoke plumes and that the GOSAT FTS (Fourier-Transform Spectrometer) TIR (Thermal InfraRed) could be used to calculate the height of the plumes at approximately 800 hPa (1.58 km). Using GOSAT data, we estimated that the 2010 fires in western Russia emitted 255.76 Tg CO 2 . We also calculated the CO 2 emissions by employing the Biomass Burning Model (BBM) for the same study site and obtained a similar result of 261.82-302.48 Tg CO 2 . The present study proposes a new method for the evaluation of CO 2 emissions from a wildfire using remote sensing data, which could be used to improve the knowledge of the burning of biomass at a regional or a continental scale, to reduce the uncertainties in modeling greenhouse gases emissions, and to further understand how wildfires impact the atmospheric carbon cycle and global warming. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methane over South Asian region from GOSAT observations and ACTM simulations

NASA Astrophysics Data System (ADS)

Chandra, N.; Hayashida, S.; Patra, P. K.; Saeki, T.

2017-12-01

Methane (CH4) is one of the most important short-lived climate forcers. About 8% of global CH4 emissions are estimated from South Asia, covering less than 1% of global land. However, large uncertainty prevails in the sectorial CH4 emissions because of the lack of measurements. With the availability of total column methane (XCH4) observations by satellites, variability in XCH4 have been captured for most parts of the global land with major emissions, which were otherwise not covered by the surface observation network. However, direct use of satellite data for estimating emissions by inversion analysis is highly ambiguous, unlike the in-situ measurements near the source region, XCH4 values are controlled by surface emission and CH4 abundances at all altitudes. Therefore, understanding the role of transport along with the emissions on XCH4 is necessary before using the XCH4 data for the inversion analysis. We analyzed XCH4 observed by the GHGs Observation SATellite (GOSAT) and simulations over the South Asia region using the JAMSTEC's atmospheric chemistry-transport model (ACTM). The analysis suggests that distinct XCH4 seasonal cycle over northern and southern regions of India is governed by the both heterogeneous distributions of surface emissions and variability in partial CH4 column in the upper troposphere. Using ACTM simulations, we find that over most part of the northern Indian regions up to 40% of the seasonal peak during the southwest (SW) monsoon is attributed to the lower troposphere ( 1000-600 hPa), while 40% to uplifted high-CH4 air masses in the upper troposphere ( 600-200 hPa). In contrast, XCH4 seasonal enhancement over the semi-arid region, with extremely low CH4 emissions, is attributed mainly ( 70%) to partial XCH4 variability in the upper troposphere. The lower tropospheric region contributes up to 60% in the XCH4 seasonal enhancement over the southern peninsula and oceanic region. These differences arise from the complex atmospheric transport

An Inversion Analysis of Recent Variability in Natural CO2 Fluxes Using GOSAT and In Situ Observations

NASA Astrophysics Data System (ADS)

Wang, J. S.; Kawa, S. R.; Baker, D. F.; Collatz, G. J.; Ott, L. E.

2015-12-01

About one-half of the global CO2 emissions from fossil fuel combustion and deforestation accumulates in the atmosphere, where it contributes to global warming. The rest is taken up by vegetation and the ocean. The precise contribution of the two sinks, and their location and year-to-year variability are, however, not well understood. We use two different approaches, batch Bayesian synthesis inversion and variational data assimilation, to deduce the global spatiotemporal distributions of CO2 fluxes during 2009-2010. One of our objectives is to assess different sources of uncertainties in inferred fluxes, including uncertainties in prior flux estimates and observations, and differences in inversion techniques. For prior constraints, we utilize fluxes and uncertainties from the CASA-GFED model of the terrestrial biosphere and biomass burning driven by satellite observations and interannually varying meteorology. We also use measurement-based ocean flux estimates and two sets of fixed fossil CO2 emissions. Here, our inversions incorporate column CO2 measurements from the GOSAT satellite (ACOS retrieval, filtered and bias-corrected) and in situ observations (individual flask and afternoon-average continuous observations) to estimate fluxes in 108 regions over 8-day intervals for the batch inversion and at 3° x 3.75° weekly for the variational system. Relationships between fluxes and atmospheric concentrations are derived consistently for the two inversion systems using the PCTM atmospheric transport model driven by meteorology from the MERRA reanalysis. We compare the posterior fluxes and uncertainties derived using different data sets and the two inversion approaches, and evaluate the posterior atmospheric concentrations against independent data including aircraft measurements. The optimized fluxes generally resemble those from other studies. For example, the results indicate that the terrestrial biosphere is a net CO2 sink, and a GOSAT-only inversion suggests a

An Inversion Analysis of Recent Variability in Natural CO2 Fluxes Using GOSAT and In Situ Observations

NASA Technical Reports Server (NTRS)

Wang, James S.; Kawa, S. Randolph; Collatz, G. James; Baker, David F.; Ott, Lesley

2015-01-01

About one-half of the global CO2 emissions from fossil fuel combustion and deforestation accumulates in the atmosphere, where it contributes to global warming. The rest is taken up by vegetation and the ocean. The precise contribution of the two sinks, and their location and year-to-year variability are, however, not well understood. We use two different approaches, batch Bayesian synthesis inversion and variational data assimilation, to deduce the global spatiotemporal distributions of CO2 fluxes during 2009-2010. One of our objectives is to assess different sources of uncertainties in inferred fluxes, including uncertainties in prior flux estimates and observations, and differences in inversion techniques. For prior constraints, we utilize fluxes and uncertainties from the CASA-GFED model of the terrestrial biosphere and biomass burning driven by satellite observations and interannually varying meteorology. We also use measurement-based ocean flux estimates and two sets of fixed fossil CO2 emissions. Here, our inversions incorporate column CO2 measurements from the GOSAT satellite (ACOS retrieval, filtered and bias-corrected) and in situ observations (individual flask and afternoon-average continuous observations) to estimate fluxes in 108 regions over 8-day intervals for the batch inversion and at 3 x 3.75 weekly for the variational system. Relationships between fluxes and atmospheric concentrations are derived consistently for the two inversion systems using the PCTM atmospheric transport model driven by meteorology from the MERRA reanalysis. We compare the posterior fluxes and uncertainties derived using different data sets and the two inversion approaches, and evaluate the posterior atmospheric concentrations against independent data including aircraft measurements. The optimized fluxes generally resemble those from other studies. For example, the results indicate that the terrestrial biosphere is a net CO2 sink, and a GOSAT-only inversion suggests a shift in

Viewing the effects of anthropogenic emission control from the change of CO2 concentration observed by GOSAT in China during the 2014 APEC summit

NASA Astrophysics Data System (ADS)

Lei, L.; Zhong, H.; Liu, L.; Yang, S., Sr.

2016-12-01

The growth of the global anthropogenic carbon emission stalled in 2014, according to data from International Energy Agency (IEA). This paper presents a practical application of satellite observation for detecting the regional enhancement of CO2 induced by underlying anthropogenic CO2 emissions especially during the 2014 Asia-Pacific Economic Cooperation (APEC) summit. We collected the column averaged dry air mole fraction (XCO2) data from Greenhouse Observation SATellite (GOSAT) from Jan. 2010 to Dec. 2015, which are provided by Japan GOSAT project team. The spatial change of the 5-year averaged XCO2 derived by gap filling [Zeng et al., TGRS, 2014], as shown in Fig.1, demonstrated that high XCO2prefer to correspond to the most intensive power plants. We calculated the regional contrasts between source and almost without emission (Fig.2), which are defined based on emission and potential temperature. The source, which is defined around Beijing, has many big power plants (Fig.1). The regional contrast showed 1-3 ppm with large seasonal variations while it is the lowest in summer due to influence of biospheric fluxes and especially show abnormal fluctuation in autumn 2014 (Fig.3). XCO2 fell from 398.9 ppm in 15-30 Oct. before APEC to 395.7 ppm during 1-11 Nov. 2014 APEC in source area around Beijing, and the contrast decreased from 4.5 ppm to 1.0 ppm (Table 1). This abnormal decline of XCO2 likely indicate the effects of controlling action for strong local source emissions such as closed many small inefficient coal-fired power plants from the beginning of 2014, banned on burning straw, especially in addition to temporally shut down the big coal-power plants and limiting the number of vehicles running during the APEC summit within the large zone covering the six provinces around Beijing. The large reduction was reported in aerosol of 50% above during the APEC summit (Sun et al., Sci. report, 2016). Our results agree to the potential of satellite observations to

Disturbances and their corrections in space observation with GOSAT Fourier transform spectrometer

NASA Astrophysics Data System (ADS)

Aoki, Tadao; Yokota, Tatsuya; Inoue, Gen; Nobuta, Koji; Kotani, Akira

2007-10-01

GOSAT (Greenhouse Gases Observing Satellite) is a satellite to measure greenhouse gases from space with the Fourier Transform Spectrometer (FTS). It measures spectra of Earth-reflected solar radiations with high spectral resolution of about 0.2 cm -1, covering four spectral bands, including 0.76, 1.6, 2.0 and 14 micron wavelength regions. In first three bands, we have two detectors for measuring two components of polarization. For the acquisition of one interferogram, it takes 4 seconds or less, depending on the definition of measurement mode. Since the satellite moves in high speed, an image motion compensation mirror (IMC) works to continuously stare the same position on the Earth surface during this period of acquisition. For staring same position, the mirror is controlled by two-axis motors. Staring position could slightly fluctuate around the right position, making the position of the instantaneous filed of view (IFOV) vibrate with an amplitude of a few hundreds meters. Since the optical characteristics (such as the albedo) of the IFOV changes place-by-place, the intensity of IFOV could also change due to this fluctuation. The intensity of IFOV could also change due to the change of reflection angle, wind on the water surface, or other causes. During this period of the acquisition, the optical path length and Doppler shift caused by the satellite moving could also change. In this paper, we examine the effects of some of these kinds of disturbances to the signals of interferograms on resultant spectra and retrieval accuracies of CO II, and discuss about the correction method to the interferogram and spectra.

Overview of Japanese Earth observation programs

NASA Astrophysics Data System (ADS)

Shimoda, Haruhisa; Honda, Yoshiaki

2017-09-01

Five programs, i.e. ASTER, GOSAT, GCOM-W1, GPM and ALOS-2 are going on in Japanese Earth Observation programs. ASTER has lost its short wave infrared channels. AMSR-E stopped its operation, but it started its operation from Sep. 2012 with slow rotation speed. It finally stopped on December 2015. GCOM-W1 was launched on 18, May, 2012 and is operating well as well as GOSAT. ALOS (Advanced Land Observing Satellite) was successfully launched on 24th Jan. 2006. ALOS carries three instruments, i.e., PRISM (Panchromatic Remote Sensing Instrument for Stereo Mapping), AVNIR-2 (Advanced Visible and Near Infrared Radiometer), and PALSAR (Phased Array L band Synthetic Aperture Radar). Unfortunately, ALOS has stopped its operation on 22nd, April, 2011 by power loss. GOSAT (Greenhouse Gas Observation Satellite) was successfully launched on 29, January, 2009. GOSAT carries 2 instruments, i.e. a green house gas sensor (TANSO-FTS) and a cloud/aerosol imager (TANSO-CAI). The main sensor is a Fourier transform spectrometer (FTS) and covers 0.76 to 15 μm region with 0.2 to 0.5 cm-1 resolution. SMILES (Superconducting Millimeter wave Emission Spectrometer) was launched on September 2009 to ISS and started the observation, but stopped its operation on April 2010. GPM (Global Precipitation Mission) core satellite was launched on Feb. 2014. GPM is a joint project with NASA and carries two instruments. JAXA has developed DPR (Dual frequency Precipitation Radar) which is a follow on of PR on TRMM. ALOS F/O satellites are divided into two satellites, i.e. SAR and optical satellites. The first one of ALOS F/O is called ALOS 2 and carries L-band SAR. It was launched on May 2014. JAXA is planning to launch follow on of optical sensors. It is now called Advanced Optical Satellite and the planned launch date is fiscal 2019. Other future satellites are GCOM-C1 (ADEOS-2 follow on), GOSAT-2 and EarthCare. GCOM-C1 will be launched on 2017 and GOSAT-2 will be launched on fiscal 2018. Another project

Simultaneous retrieval of atmospheric CO2 and light path modification from space-based spectroscopic observations of greenhouse gases: methodology and application to GOSAT measurements over TCCON sites.

PubMed

Oshchepkov, Sergey; Bril, Andrey; Yokota, Tatsuya; Yoshida, Yukio; Blumenstock, Thomas; Deutscher, Nicholas M; Dohe, Susanne; Macatangay, Ronald; Morino, Isamu; Notholt, Justus; Rettinger, Markus; Petri, Christof; Schneider, Matthias; Sussman, Ralf; Uchino, Osamu; Velazco, Voltaire; Wunch, Debra; Belikov, Dmitry

2013-02-20

This paper presents an improved photon path length probability density function method that permits simultaneous retrievals of column-average greenhouse gas mole fractions and light path modifications through the atmosphere when processing high-resolution radiance spectra acquired from space. We primarily describe the methodology and retrieval setup and then apply them to the processing of spectra measured by the Greenhouse gases Observing SATellite (GOSAT). We have demonstrated substantial improvements of the data processing with simultaneous carbon dioxide and light path retrievals and reasonable agreement of the satellite-based retrievals against ground-based Fourier transform spectrometer measurements provided by the Total Carbon Column Observing Network (TCCON).

Assessing systematic errors in GOSAT CO2 retrievals by comparing assimilated fields to independent CO2 data

NASA Astrophysics Data System (ADS)

Baker, D. F.; Oda, T.; O'Dell, C.; Wunch, D.; Jacobson, A. R.; Yoshida, Y.; Partners, T.

2012-12-01

Measurements of column CO2 concentration from space are now being taken at a spatial and temporal density that permits regional CO2 sources and sinks to be estimated. Systematic errors in the satellite retrievals must be minimized for these estimates to be useful, however. CO2 retrievals from the TANSO instrument aboard the GOSAT satellite are compared to similar column retrievals from the Total Carbon Column Observing Network (TCCON) as the primary method of validation; while this is a powerful approach, it can only be done for overflights of 10-20 locations and has not, for example, permitted validation of GOSAT data over the oceans or deserts. Here we present a complementary approach that uses a global atmospheric transport model and flux inversion method to compare different types of CO2 measurements (GOSAT, TCCON, surface in situ, and aircraft) at different locations, at the cost of added transport error. The measurements from any single type of data are used in a variational carbon data assimilation method to optimize surface CO2 fluxes (with a CarbonTracker prior), then the corresponding optimized CO2 concentration fields are compared to those data types not inverted, using the appropriate vertical weighting. With this approach, we find that GOSAT column CO2 retrievals from the ACOS project (version 2.9 and 2.10) contain systematic errors that make the modeled fit to the independent data worse. However, we find that the differences between the GOSAT data and our prior model are correlated with certain physical variables (aerosol amount, surface albedo, correction to total column mass) that are likely driving errors in the retrievals, independent of CO2 concentration. If we correct the GOSAT data using a fit to these variables, then we find the GOSAT data to improve the fit to independent CO2 data, which suggests that the useful information in the measurements outweighs the negative impact of the remaining systematic errors. With this assurance, we compare

Validation of OCO-2 and ACOS-GOSAT using HIPPO and TCCON

NASA Technical Reports Server (NTRS)

Kulawik, Susan S.; Wunch, Debra; O'Dell, Christopher; Miller, Charles; Osterman, Greg; Wennberg, Paul; Griffith, David; Sherlock, Vanessa; Deutscher, Nicholas M.; Notholt, Justus;

Methane Flux Estimation from Point Sources using GOSAT Target Observation: Detection Limit and Improvements with Next Generation Instruments

NASA Astrophysics Data System (ADS)

Kuze, A.; Suto, H.; Kataoka, F.; Shiomi, K.; Kondo, Y.; Crisp, D.; Butz, A.

2017-12-01

Atmospheric methane (CH4) has an important role in global radiative forcing of climate but its emission estimates have larger uncertainties than carbon dioxide (CO2). The area of anthropogenic emission sources is usually much smaller than 100 km2. The Thermal And Near infrared Sensor for carbon Observation Fourier-Transform Spectrometer (TANSO-FTS) onboard the Greenhouse gases Observing SATellite (GOSAT) has measured CO2 and CH4 column density using sun light reflected from the earth's surface. It has an agile pointing system and its footprint can cover 87-km2 with a single detector. By specifying pointing angles and observation time for every orbit, TANSO-FTS can target various CH4 point sources together with reference points every 3 day over years. We selected a reference point that represents CH4 background density before or after targeting a point source. By combining satellite-measured enhancement of the CH4 column density and surface measured wind data or estimates from the Weather Research and Forecasting (WRF) model, we estimated CH4emission amounts. Here, we picked up two sites in the US West Coast, where clear sky frequency is high and a series of data are available. The natural gas leak at Aliso Canyon showed a large enhancement and its decrease with time since the initial blowout. We present time series of flux estimation assuming the source is single point without influx. The observation of the cattle feedlot in Chino, California has weather station within the TANSO-FTS footprint. The wind speed is monitored continuously and the wind direction is stable at the time of GOSAT overpass. The large TANSO-FTS footprint and strong wind decreases enhancement below noise level. Weak wind shows enhancements in CH4, but the velocity data have large uncertainties. We show the detection limit of single samples and how to reduce uncertainty using time series of satellite data. We will propose that the next generation instruments for accurate anthropogenic CO2 and CH

GOSAT TIR spectral validation with High/Low temperature target using Aircraft base-FTS S-HIS

NASA Astrophysics Data System (ADS)

Kataoka, F.; Knuteson, R.; Taylor, J. K.; Kuze, A.; Shiomi, K.; Suto, H.; Yoshida, J.

2017-12-01

The Greenhouse gases Observing SATellite (GOSAT) was launched on January 2009. The GOSAT is equipped with TANSO-FTS (Fourier-Transform Spectrometer), which observe reflected solar radiation from the Earth's surface with shortwave infrared (SWIR) band and thermal emission from the Earth's surface and atmosphere with thermal infrared (TIR) band. The TIR band cover wide spectral range (650 - 1800 [cm-1]) with a high spectral resolution (0.2 [cm-1]). The TIR spectral information provide vertical distribution of CO2 and CH4. GOSAT has been operation more than eight years. In this long operation, GOSAT had experienced two big accidents; Rotation of one of the solar paddles stopped and sudden TANSO-FTS operation stop in May 2014 and cryocooler shutdown and restart in August - September 2015. These events affected the operation condition of the TIR photo-conductive (PC)-MCT detector. FTS technology using multiplex wide spectra needs wide dynamic range. PC detector has nonlinearity. Its correction needs accurate estimation of time-dependent offset. In current TIR Level 1B product version (V201), the non-photon level offset (Vdc_offset) estimated from on-orbit deep space calibration data and pre-launch background radiation model. But the background radiation and detector temperature have changed after cryocooler shutdown events. These changes are too small to detect from onboard temperature sensors. The next TIR Level 1B product uses cross calibration data together with deep space calibration data and instrument radiation model has been updated. This work describes the evaluation of new TIR Level 1B spectral quality with aircraft-based FTS; Scanning High-resolution Interferometer Sounder (S-HIS). The S-HIS mounted on the high-altitude ER-2 aircraft and flew at about 20km altitude. Because the observation geometry of GOSAT and S-HIS are quite different, we used the double difference method using atmospheric transfer model. GOSAT TIR band cover wide dynamic range, so we check

Adaptation of an aerosol retrieval algorithm using multi-wavelength and multi-pixel information of satellites (MWPM) to GOSAT/TANSO-CAI

NASA Astrophysics Data System (ADS)

Hashimoto, M.; Takenaka, H.; Higurashi, A.; Nakajima, T.

2017-12-01

Aerosol in the atmosphere is an important constituent for determining the earth's radiation budget, so the accurate aerosol retrievals from satellite is useful. We have developed a satellite remote sensing algorithm to retrieve the aerosol optical properties using multi-wavelength and multi-pixel information of satellite imagers (MWPM). The method simultaneously derives aerosol optical properties, such as aerosol optical thickness (AOT), single scattering albedo (SSA) and aerosol size information, by using spatial difference of wavelegths (multi-wavelength) and surface reflectances (multi-pixel). The method is useful for aerosol retrieval over spatially heterogeneous surface like an urban region. In this algorithm, the inversion method is a combination of an optimal method and smoothing constraint for the state vector. Furthermore, this method has been combined with the direct radiation transfer calculation (RTM) numerically solved by each iteration step of the non-linear inverse problem, without using look up table (LUT) with several constraints. However, it takes too much computation time. To accelerate the calculation time, we replaced the RTM with an accelerated RTM solver learned by neural network-based method, EXAM (Takenaka et al., 2011), using Rster code. And then, the calculation time was shorternd to about one thouthandth. We applyed MWPM combined with EXAM to GOSAT/TANSO-CAI (Cloud and Aerosol Imager). CAI is a supplement sensor of TANSO-FTS, dedicated to measure cloud and aerosol properties. CAI has four bands, 380, 674, 870 and 1600 nm, and observes in 500 meters resolution for band1, band2 and band3, and 1.5 km for band4. Retrieved parameters are aerosol optical properties, such as aerosol optical thickness (AOT) of fine and coarse mode particles at a wavelenth of 500nm, a volume soot fraction in fine mode particles, and ground surface albedo of each observed wavelength by combining a minimum reflectance method and Fukuda et al. (2013). We will show

Discussion of vicarious calibration of GOSAT/TANSO-CAI UV-band (380nm) and aerosol retrieval in wildfire region in the OCO-2 and GOSAT observation campaign at Railroad Valley in 2016

NASA Astrophysics Data System (ADS)

Hashimoto, M.; Kuze, A.; Bruegge, C. J.; Shiomi, K.; Kataoka, F.; Kikuchi, N.; Arai, T.; Kasai, K.; Nakajima, T.

2016-12-01

The GOSAT (Greenhouse Gases Observing Satellite) / TANSO-CAI (Cloud and Aerosol Imager, CAI) is an imaging sensor to measure cloud and aerosol properties and observes reflected sunlight from the atmosphere and surface of the ground. The sensor has four bands from near ultraviolet (near-UV) to shortwave infrared, 380, 674, 870 and 1600nm. The field of view size is 0.5 km for band-1 through band-3, and 1.5km for band-4. Band-1 (380nm) is one of unique function of the CAI. The near-UV observation offers several advantages for the remote sensing of aerosols over land: Low reflectance of most surfaces; Sensitivity to absorbing aerosols; Absorption of trace gases is weak (Höller et al., 2004). CAI UV-band is useful to distinguish absorbing aerosol (smoke) from cloud. GOSAT-2/TANSO-CAI-2 that will be launched in the future also has UV-bands, 340 and 380nm. We carried out an experiment to calibrate CAI UV-band radiance using data taken in a field campaign of OCO-2 and GOSAT at Railroad Valley in 2016. The campaign period is June 27 to July 3 in 2016. We measured surface reflectance by using USB4000 Spectrometer with 74-UV collimating lens (Ocean Optics) and Spectralon (Labsphere). USB4000 is a UV spectrometer, and its measurement range from 300 to 520nm. We simulated CAI UV-band radiance using a vector type of radiation transfer code, i.e. including polarization calculation, pstar3 (Ota et al., 2010) using measured surface reflectance and atmospheric data, pressure and relative humidity by radiosonde in the same campaign, and aerosol optical depth by AERONET, etc. Then, we evaluated measured UV radiances with the simulated data. We show the result of vicarious calibration of CAI UV-band in the campaign, and discuss about this method for future sensor, CAI-2. Around the campaign period, there was wildfire around Los Angeles, and aerosol optical thickness (AOT) observed by AERONET at Rail Road valley and Caltech sites is also high. We tried to detect and retrieve aerosol

Seasonal Variations of Atmospheric CO2 over Fire Affected Regions Based on GOSAT Observations

NASA Astrophysics Data System (ADS)

Shi, Y.; Matsunaga, T.

2016-12-01

Abstract: The carbon dioxide (CO2) emissions released from biomass burning significantly affect the temporal variations of atmospheric CO2 concentrations. Based on a long-term (July 2009-June 2015) retrieved datasets by the Greenhouse Gases Observing Satellite (GOSAT), the seasonal cycle and interannual variations of column-averaged volume mixing ratios of atmospheric carbon dioxide (XCO2) in four fire affected continental regions were investigated. The results showed Northern Africa had the largest seasonal variations after removing its regional long-term trend of XCO2 with peak-to-peak amplitude of 6.2 ppm within the year, higher than central South America (2.4 ppm), Southern Africa (3.8 ppm) and Australia (1.7 ppm). The detrended regional XCO2 was found to be positively correlated with the fire CO2 emissions during fire activity period and negatively correlated with vegetation photosynthesis activity with different seasonal variabilities. Northern Africa recorded the largest change of seasonal variations of detrended XCO2 with a total of 12.8 ppm during fire seasons, higher than central South America, Southern Africa and Australia with 5.4 ppm, 6.7 ppm and 2.2 ppm, respectively. During fire episode, the positive detrended XCO2 was noticed during June-November in central South America, December-June in Northern Africa, May-November in Southern Africa. The Pearson correlation coefficients between the variations of detrended XCO2 and fire CO2 emissions from GFED4 (Global Fire Emissions Database v4) achieved best correlations in Southern Africa (R=0.77, p<0.05). Meanwhile, Southern Africa also experienced a significant negative relationship between the variations of detrended XCO2 and vegetation activity (R=-0.84, p<0.05). This study revealed that fire CO2 emissions and vegetation activity contributed greatly to the seasonal variations of GOSAT XCO2 dataset.

Examination about the Impact of Thin Clouds in IFOV of GOSAT TANSO-FTS on Estimates of XCO2 in the Amazon

NASA Astrophysics Data System (ADS)

Oishi, Y.; Kamei, A.; Murakami, K.; Dupuy, E.; Yokota, Y.; Hiraki, K.; Ninomiya, K.; Saito, M.; Yoshida, Y.; Morino, I.; Nakajima, T. Y.; Yokota, T.; Matsunaga, T.

2013-12-01

Greenhouse gases Observing SATellite (GOSAT) was launched in 2009 to measure the global atmospheric CO2 and CH4 concentrations. GOSAT is equipped with two sensors: the Thermal And Near-infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) and the Cloud and Aerosol Imager (TANSO-CAI). The presence of clouds in the instantaneous field-of-view (IFOV) of the FTS leads to incorrect estimates of the CO2 or CH4 concentration. To deal with this problem, the FTS data which are suspected to be cloud-contaminated must be identified and rejected. As a result, there are very few remaining FTS data in the region of tropical rainforest such as the Amazon. In the meanwhile the feasibility studies of GOSAT-2 started for more precise monitoring of atmospheric greenhouse gases than GOSAT in 2011. To improve the accuracy of estimates of the column-averaged dry air mole fraction of atmospheric CO2 (XCO2), we need to understand the present situation about cloud screening in the rain forest regions and to examine the cloud-contaminated data whose processing might be possible with improvement of instruments or algorithms. In this study we evaluated the impact of thin clouds on estimates of the XCO2 using an atmospheric radiative transfer code, which can simulate the spectrum at the top of the atmosphere under thin cloud conditions. First, we decided the input parameters, among which relative position of the sun and satellite to observation point, surface reflectance using cloud-free GOSAT data products in the Amazon, FTS L1B data products (radiance spectral data), FTS L2 data products (CO2 column abundance data), and CAI L3 data products (clear-sky reflectance data). The evaluation was performed by comparing depths of the CO2 absorption lines in output radiation spectra with varying CO2 concentrations and cloud conditions, cloud type, cloud optical depth, and cloud top altitude. We will present our latest results.

Monitoring carbon dioxide from space: Retrieval algorithm and flux inversion based on GOSAT data and using CarbonTracker-China

NASA Astrophysics Data System (ADS)

Yang, Dongxu; Zhang, Huifang; Liu, Yi; Chen, Baozhang; Cai, Zhaonan; Lü, Daren

2017-08-01

Monitoring atmospheric carbon dioxide (CO2) from space-borne state-of-the-art hyperspectral instruments can provide a high precision global dataset to improve carbon flux estimation and reduce the uncertainty of climate projection. Here, we introduce a carbon flux inversion system for estimating carbon flux with satellite measurements under the support of "The Strategic Priority Research Program of the Chinese Academy of Sciences—Climate Change: Carbon Budget and Relevant Issues". The carbon flux inversion system is composed of two separate parts: the Institute of Atmospheric Physics Carbon Dioxide Retrieval Algorithm for Satellite Remote Sensing (IAPCAS), and CarbonTracker-China (CT-China), developed at the Chinese Academy of Sciences. The Greenhouse gases Observing SATellite (GOSAT) measurements are used in the carbon flux inversion experiment. To improve the quality of the IAPCAS-GOSAT retrieval, we have developed a post-screening and bias correction method, resulting in 25%-30% of the data remaining after quality control. Based on these data, the seasonal variation of XCO2 (column-averaged CO2 dry-air mole fraction) is studied, and a strong relation with vegetation cover and population is identified. Then, the IAPCAS-GOSAT XCO2 product is used in carbon flux estimation by CT-China. The net ecosystem CO2 exchange is -0.34 Pg C yr-1 (±0.08 Pg C yr-1), with a large error reduction of 84%, which is a significant improvement on the error reduction when compared with in situ-only inversion.

Carbon Monitoring System Flux Estimation and Attribution: Impact of ACOS-GOSAT X(CO2) Sampling on the Inference of Terrestrial Biospheric Sources and Sinks

NASA Technical Reports Server (NTRS)

Liu, Junjie; Bowman, Kevin W.; Lee, Memong; Henze, David K.; Bousserez, Nicolas; Brix, Holger; Collatz, G. James; Menemenlis, Dimitris; Ott, Lesley; Pawson, Steven;

Filling-in of Far-Red and Near-Infrared Solar Lines by Terrestrial and Atmospheric Effects: Simulations and Space-Based Observations from SCIAMACHY and GOSAT

NASA Technical Reports Server (NTRS)

Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Middleton, E. M.; Campbell, P. K. E.; Yoshida, Y.; Kuse, A.; Corp, L. A.

2012-01-01

Mapping of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global information on the functional status of vegetation including light use efficiency and global primary productivity that can be used for global carbon cycle modeling. Space-based measurement of solar-induced chlorophyll fluorescence is challenging, because its signal is small as compared with the much larger reflectance signal. Ground- and aircraft-based approaches have made use of the dark and spectrally-wide O2-A ( approx 760 nm) and O2-B (approx 690 nm) atmospheric features to detect the weak fluorescence signal. More recently, Joiner et al. and Frankenberg et al. focused on longer-wavelength solar Fraunhofer lines that can be observed with space-based instruments such as the currently operational GOSAT. They showed that fluorescence can be detected using Fraunhofer lines away from the far-red chlorophyll-a fluorescence peak even when the surface is relatively bright. Here, we build on that work by developing methodology to correct for instrumental artifacts that produce false filling-in signals that can bias fluorescence retrievals. We also examine other potential sources of filling-in at far-red and NIR wavelengths. Another objective is to explore the possibility of making fluorescence measurements from space with lower spectral resolution instrumentation than the GOSAT interferometer. We focus on the 866nm Ca II solar Fraunhofer line. Very few laboratory and ground-based measurements of vegetation fluorescence have been reported at wavelengths longer than 800 nm. Some results of fluorescence measurements of corn leaves acquired in the laboratory using polychromatic excitation at wavelengths shorter than 665nm show that at 866 nm, the measured signal is of the order of 0.1-0.2 mW/sq m/nm/sr. In this work, we use the following satellite observations: We use SCIAMACHY channel 5 in nadir mode that covers wavelengths between 773 and 1063nm at a spectral

Filling-in of Far-Red and Near-Infrared Solar Lines by Terrestrial and Atmospheric Effects: Simulations and Space-Based Observations from SCHIAMACHY and GOSAT

NASA Technical Reports Server (NTRS)

Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Middleton, E. M.; Campbell, P. K. E.; Kuze, A.; Corp, L. A.

2012-01-01

Mapping of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global information on the functional status of vegetation including light use efficiency and global primary productivity that can be used for global carbon cycle modeling. Space-based measurement of solar-induced chlorophyll fluorescence is challenging, because its signal is small as compared with the much larger reflectance signal. Ground- and aircraft-based approaches have made use of the dark and spectrally-wide 02-A (approx 760 nm) and O2-B (approx 690 nm) atmospheric features to detect the weak fluorescence signal. More recently, Joiner et a1. and Frankenberg et a1. focused on longer-wavelength solar Fraunhofer lines that can be observed with space-based instruments such as the currently operational GOSAT. They showed that fluorescence can be detected using Fraunhofer lines away from the far-red chlorophyll-a fluorescence peak even when the surface is relatively bright. Here, we build on that work by developing methodology to correct for instrumental artifacts that produce false filling-in signals that can bias fluorescence retrievals. We also examine other potential sources of filling-in at far-red and NIR wavelengths. Another objective is to explore the possibility of making fluorescence measurements from space with lower spectral resolution instrumentation than the GOSAT interferometer. We focus on the 866 nm Ca II solar Fraunhofer line. Very few laboratory and ground-based measurements of vegetation fluorescence have been reported at wavelengths longer than 800 mn. Some results of fluorescence measurements of corn leaves acquired in the laboratory using polychromatic excitation at wavelengths shorter than 665 nm show that at 866 nm, the measured signal is of the order of 0.1-0.2 mw/sq m/nm/sr. In this work we use the following satellite observations: We use SCIAMACHY channel 5 in nadir mode that covers wavelengths between 773 and 1063 nm at a

Toward Global Mapping of Methane With TROPOMI: First Results and Intersatellite Comparison to GOSAT

NASA Astrophysics Data System (ADS)

Hu, Haili; Landgraf, Jochen; Detmers, Rob; Borsdorff, Tobias; Aan de Brugh, Joost; Aben, Ilse; Butz, André; Hasekamp, Otto

2018-04-01

The TROPOspheric Monitoring Instrument (TROPOMI), launched on 13 October 2017, aboard the Sentinel-5 Precursor satellite, measures reflected sunlight in the ultraviolet, visible, near-infrared, and shortwave infrared spectral range. It enables daily global mapping of key atmospheric species for monitoring air quality and climate. We present the first methane observations from November and December 2017, using TROPOMI radiance measurements in the shortwave infrared band around 2.3 μm. We compare our results with the methane product obtained from the Greenhouse gases Observing SATellite (GOSAT). Although different spectral ranges and retrieval methods are used, we find excellent agreement between the methane products acquired from the two satellites with a mean difference of 13.6 ppb, standard deviation of 19.6 ppb, and Pearson's correlation coefficient of 0.95. Our preliminary results capture the latitudinal gradient and show expected regional enhancements, for example, in the African Sudd wetlands, with much more detail than has been observed before.

What controls the seasonal cycle of columnar methane observed by GOSAT over different regions in India?

NASA Astrophysics Data System (ADS)

Chandra, Naveen; Hayashida, Sachiko; Saeki, Tazu; Patra, Prabir K.

2017-10-01

Methane (CH4) is one of the most important short-lived climate forcers for its critical roles in greenhouse warming and air pollution chemistry in the troposphere, and the water vapor budget in the stratosphere. It is estimated that up to about 8 % of global CH4 emissions occur from South Asia, covering less than 1 % of the global land. With the availability of satellite observations from space, variability in CH4 has been captured for most parts of the global land with major emissions, which were otherwise not covered by the surface observation network. The satellite observation of the columnar dry-air mole fractions of methane (XCH4) is an integrated measure of CH4 densities at all altitudes from the surface to the top of the atmosphere. Here, we present an analysis of XCH4 variability over different parts of India and the surrounding cleaner oceanic regions as measured by the Greenhouse gases Observation SATellite (GOSAT) and simulated by an atmospheric chemistry-transport model (ACTM). Distinct seasonal variations of XCH4 have been observed over the northern (north of 15° N) and southern (south of 15° N) parts of India, corresponding to the peak during the southwestern monsoon (July-September) and early autumn (October-December) seasons, respectively. Analysis of the transport, emission, and chemistry contributions to XCH4 using ACTM suggests that a distinct XCH4 seasonal cycle over northern and southern regions of India is governed by both the heterogeneous distributions of surface emissions and a contribution of the partial CH4 column in the upper troposphere. Over most of the northern Indian Gangetic Plain regions, up to 40 % of the peak-to-trough amplitude during the southwestern (SW) monsoon season is attributed to the lower troposphere ( ˜ 1000-600 hPa), and ˜ 40 % to uplifted high-CH4 air masses in the upper troposphere ( ˜ 600-200 hPa). In contrast, the XCH4 seasonal enhancement over semi-arid western India is attributed mainly ( ˜ 70 %) to the

An 8-Year, High-Resolution Reanalysis of Atmospheric CO2 Mixing Ratios Based on OCO-2 and GOSAT-ACOS Retrievals

NASA Technical Reports Server (NTRS)

Weir, B.; Chatterjee, A.; Ott, L. E.; Pawson, S.

2017-01-01

The NASA GMAO (Global Modeling and Assimilation Office) reanalysis blends OCO-2 (Orbiting Carbon Observatory 2) and GOSAT-ACOS (Greenhouse Gases Observing Satellite-Atmospheric Carbon Observations from Space) retrievals (top) with GEOS (Goddard Earth Observing System) model predictions (bottom) to estimate the full 3D (three-dimensional) state of CO2 every 3 hours (middle). This poster describes monthly atmospheric growth rates derived from the reanalysis and an application to aircraft data with the potential to aid bias correction.

Clustering XCO2 temporal change to assess CO2 exchanging strength of biosphere-atmosphere with GOSAT observations

NASA Astrophysics Data System (ADS)

He, Zhonghua; Lei, Liping; Bie, Nian; Yang, Shaoyuan; Wu, Changjiang; Zeng, Zhao-Cheng

2017-04-01

The temporal change of atmospheric carbon dioxide (CO2) concentration, greatly related to the local activities of CO2 uptake and emission, including biospheric exchange and anthropogenic emission, is one of important information for regions identification of carbon source and sink. Satellite observations of CO2 has been used for detecting the change of CO2 concentration for a long time. In this study, we used the grid data of column-averaged CO2 dry air mole fraction (XCO2) with the spatial resolution of 1 degree and the temporal resolution of 3 days from 1 June 2009 to 31 May 2014 over the land area of 30° - 60° N to implement a clustering of temporal changing characteristics for the Greenhouse Gases Observing Satellite (GOSAT) XCO2 retrievals. Grid data is derived using the gap filling method of spatio-temporal geostatistics. The clustering method is one adjusted K-mean for the gap existed time-series data. As a result, types and number of clusters are specified based on the temporal characteristic of XCO2 by using the optimal clustering parameters. The biospheric absorption and surface emission of atmospheric CO2 is discussed through the analysis of the different yearly increase and seasonal amplitude of XCO2 each cluster combined with correlation analysis with vegetation index from the Moderate-resolution Imaging Spectroradiometer (MODIS) and fossil fuel CO2 emission data from Open-source Data Inventory for Anthropogenic CO2 (Odiac). Regions of strong or weak biosphere-atmosphere exchange, or significant disturbance from anthropogenic activities can be identified. In conclusion, gap filled XCO2 from satellite observations can help us to take an analysis of atmospheric CO2, results of the coupled biosphere-atmosphere, by their spatio-temporal characteristics as well as the relationship with the other remote sensing parameters e.g. MODIS related with biospheric photosynthetic or respiration activities.

Estimating regional methane surface fluxes: the relative importance of surface and GOSAT mole fraction measurements

NASA Astrophysics Data System (ADS)

Fraser, A.; Palmer, P. I.; Feng, L.; Boesch, H.; Cogan, A.; Parker, R.; Dlugokencky, E. J.; Fraser, P. J.; Krummel, P. B.; Langenfelds, R. L.; O'Doherty, S.; Prinn, R. G.; Steele, L. P.; van der Schoot, M.; Weiss, R. F.

2013-06-01

We use an ensemble Kalman filter (EnKF), together with the GEOS-Chem chemistry transport model, to estimate regional monthly methane (CH4) fluxes for the period June 2009-December 2010 using proxy dry-air column-averaged mole fractions of methane (XCH4) from GOSAT (Greenhouse gases Observing SATellite) and/or NOAA ESRL (Earth System Research Laboratory) and CSIRO GASLAB (Global Atmospheric Sampling Laboratory) CH4 surface mole fraction measurements. Global posterior estimates using GOSAT and/or surface measurements are between 510-516 Tg yr-1, which is less than, though within the uncertainty of, the prior global flux of 529 ± 25 Tg yr-1. We find larger differences between regional prior and posterior fluxes, with the largest changes in monthly emissions (75 Tg yr-1) occurring in Temperate Eurasia. In non-boreal regions the error reductions for inversions using the GOSAT data are at least three times larger (up to 45%) than if only surface data are assimilated, a reflection of the greater spatial coverage of GOSAT, with the two exceptions of latitudes >60° associated with a data filter and over Europe where the surface network adequately describes fluxes on our model spatial and temporal grid. We use CarbonTracker and GEOS-Chem XCO2 model output to investigate model error on quantifying proxy GOSAT XCH4 (involving model XCO2) and inferring methane flux estimates from surface mole fraction data and show similar resulting fluxes, with differences reflecting initial differences in the proxy value. Using a series of observing system simulation experiments (OSSEs) we characterize the posterior flux error introduced by non-uniform atmospheric sampling by GOSAT. We show that clear-sky measurements can theoretically reproduce fluxes within 10% of true values, with the exception of tropical regions where, due to a large seasonal cycle in the number of measurements because of clouds and aerosols, fluxes are within 15% of true fluxes. We evaluate our posterior methane

Estimating regional methane surface fluxes: the relative importance of surface and GOSAT mole fraction measurements

NASA Astrophysics Data System (ADS)

Fraser, A.; Palmer, P. I.; Feng, L.; Boesch, H.; Cogan, A.; Parker, R.; Dlugokencky, E. J.; Fraser, P. J.; Krummel, P. B.; Langenfelds, R. L.; O'Doherty, S.; Prinn, R. G.; Steele, L. P.; van der Schoot, M.; Weiss, R. F.

2012-12-01

We use an ensemble Kalman filter (EnKF), together with the GEOS-Chem chemistry transport model, to estimate regional monthly methane (CH4) fluxes for the period June 2009-December 2010 using proxy dry-air column-averaged mole fractions of methane (XCH4) from GOSAT (Greenhouse gases Observing SATellite) and/or NOAA ESRL (Earth System Research Laboratory) and CSIRO GASLAB (Global Atmospheric Sampling Laboratory) CH4 surface mole fraction measurements. Global posterior estimates using GOSAT and/or surface measurements are between 510-516 Tg yr-1, which is less than, though within the uncertainty of, the prior global flux of 529 ± 25 Tg yr-1. We find larger differences between regional prior and posterior fluxes, with the largest changes (75 Tg yr-1) occurring in Temperate Eurasia. In non-boreal regions the error reductions for inversions using the GOSAT data are at least three times larger (up to 45%) than if only surface data are assimilated, a reflection of the greater spatial coverage of GOSAT, with the two exceptions of latitudes > 60° associated with a data filter and over Europe where the surface network adequately describes fluxes on our model spatial and temporal grid. We use CarbonTracker and GEOS-Chem XCO2 model output to investigate model error on quantifying proxy GOSAT XCH4 (involving model XCO2) and inferring methane flux estimates from surface mole fraction data and show similar resulting fluxes, with differences reflecting initial differences in the proxy value. Using a series of observing system simulation experiments (OSSEs) we characterize the posterior flux error introduced by non-uniform atmospheric sampling by GOSAT. We show that clear-sky measurements can theoretically reproduce fluxes within 5% of true values, with the exception of South Africa and Tropical South America where, due to a large seasonal cycle in the number of measurements because of clouds and aerosols, fluxes are within 17% and 19% of true fluxes, respectively. We evaluate our

GOSAT/TANSO-FTS Measurement of Volcanic and Geothermal CO2 Emissions

NASA Astrophysics Data System (ADS)

Schwandner, Florian M.; Carn, Simon A.; Newhall, Christopher G.

2010-05-01

Approximately one tenth of the Earth's human population lives in direct reach of volcanic hazards. Being able to provide sufficiently early and scientifically sound warning is a key to volcanic hazard mitigation. Quantitative time-series monitoring of volcanic CO2 emissions will likely play a key role in such early warning activities in the future. Impending volcanic eruptions or any potentially disastrous activity that involves movement of magma in the subsurface, is often preceded by an early increase of CO2 emissions. Conventionally, volcanic CO2 monitoring is done either in campaigns of soil emission measurements (grid of one-time measuring points) that are labor intensive and slow, or by ground-based remote FTIR measurements in emission plumes. These methods are not easily available at all sites of potential activity and prohibitively costly to employ on a large number of volcanoes. In addition, both of these ground-based approaches pose a significant risk to the workers conducting these measurements. Some aircraft-based measurements have been conducted as well in the past, however these are limited by the usually meager funding situation of individual observatories, the hazard such flights pose to equipment and crew, and by the inaccessibility of parts of the plume due to ash hazards. The core motivation for this study is therefore to develop a method for volcanic CO2 monitoring from space that will provide sufficient coverage, resolution, and data quality for an application to quantitative time series monitoring and correlation with other available datasets, from a safe distance and with potentially global reach. In summary, the purpose of the proposed research is to quantify volcanic CO2 emissions using satellite-borne observations. Quantitative estimates will be useful for warning of impending volcanic eruptions, and assessing the contribution of volcanic CO2 to global GHG. Our approach encompasses method development and testing for the detection of

Can satellite-based monitoring techniques be used to quantify volcanic CO2 emissions?

NASA Astrophysics Data System (ADS)

Schwandner, Florian M.; Carn, Simon A.; Kuze, Akihiko; Kataoka, Fumie; Shiomi, Kei; Goto, Naoki; Popp, Christoph; Ajiro, Masataka; Suto, Hiroshi; Takeda, Toru; Kanekon, Sayaka; Sealing, Christine; Flower, Verity

2014-05-01

Since 2010, we investigate and improve possible methods to regularly target volcanic centers from space in order to detect volcanic carbon dioxide (CO2) point source anomalies, using the Japanese Greenhouse gas Observing SATellite (GOSAT). Our long-term goals are: (a) better spatial and temporal coverage of volcano monitoring techniques; (b) improvement of the currently highly uncertain global CO2 emission inventory for volcanoes, and (c) use of volcanic CO2 emissions for high altitude, strong point source emission and dispersion studies in atmospheric science. The difficulties posed by strong relief, orogenic clouds, and aerosols are minimized by a small field of view, enhanced spectral resolving power, by employing repeat target mode observation strategies, and by comparison to continuous ground based sensor network validation data. GOSAT is a single-instrument Earth observing greenhouse gas mission aboard JAXA's IBUKI satellite in sun-synchronous polar orbit. GOSAT's Fourier-Transform Spectrometer (TANSO-FTS) has been producing total column XCO2 data since January 2009, at a repeat cycle of 3 days, offering great opportunities for temporal monitoring of point sources. GOSAT's 10 km field of view can spatially integrate entire volcanic edifices within one 'shot' in precise target mode. While it doesn't have any spatial scanning or mapping capability, it does have strong spectral resolving power and agile pointing capability to focus on several targets of interest per orbit. Sufficient uncertainty reduction is achieved through comprehensive in-flight vicarious calibration, in close collaboration between NASA and JAXA. Challenges with the on-board pointing mirror system have been compensated for employing custom observation planning strategies, including repeat sacrificial upstream reference points to control pointing mirror motion, empirical individualized target offset compensation, observation pattern simulations to minimize view angle azimuth. Since summer 2010

Observations of tropospheric trace gases from GOSAT thermal infrared spectra

NASA Astrophysics Data System (ADS)

Ohyama, Hirofumi; Shiomi, Kei; Kawakami, Shuji; Nakajima, Masakatsu; Maki, Takashi; Deushi, Makoto

2013-04-01

Thermal And Near infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS), which is one of the sensors onboard the Greenhouse gases Observing SATellite (GOSAT), measures the sunlight backscattered by the Earth's surface and atmosphere as well as the thermal radiance emitted from the Earth. Atmospheric trace gases such as ozone (O3), water vapor (H2O and HDO), methanol (CH3OH) and ammonia (NH3) are derived from the thermal infrared spectral radiance recorded with the TANSO-FTS by an optimal estimation retrieval approach. TANSO-FTS total ozone columns are compared with Dobson spectrophotometer and Ozone Monitoring Instrument (OMI) data. The TANSO-FTS total ozone retrievals exhibit a positive bias of 3-4% with a root-mean-square difference of 2-6% compared to the Dobson and OMI measurements. We compare TANSO-FTS tropospheric ozone columns to those from ozonesonde data as well as from a three-dimensional chemical-climate model (MRI-CCM2). The TANSO-FTS data have high correlations with the ozonesonde data. The seasonal trends of the retrieved tropospheric ozone are consistent with those of the ozonesonde data. The spatial distribution of the tropospheric ozone from the TANSO-FTS and MRI-CCM2 shows good agreement, especially in the high-level tropospheric ozone regions. We also retrieve tropospheric H2O and HDO profiles simultaneously, accounting for the cross correlations between the water isotopes. The joint retrieval results in precise estimation of the isotope ratio by partial cancellation of systematic errors common to both H2O and HDO. The retrieved profiles and columns are compared with radiosonde, GPS, and ground-based high-resolution FTS data. The temporal and spatial variations of the precipitable water and the isotope ratio are consistent with those of the validation data. Finally, air pollutants such as CH3OH and NH3 are retrieved using the retrieved ozone and water vapor. We present the latitudinal and seasonal variations of CH3OH

Impact of line parameter database and continuum absorption on GOSAT TIR methane retrieval

NASA Astrophysics Data System (ADS)

Yamada, A.; Saitoh, N.; Nonogaki, R.; Imasu, R.; Shiomi, K.; Kuze, A.

2017-12-01

The current methane retrieval algorithm (V1) at wavenumber range from 1210 cm-1 to 1360 cm-1 including CH4 ν 4 band from the thermal infrared (TIR) band of Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) onboard Greenhouse Gases Observing Satellite (GOSAT) uses LBLRTM V12.1 with AER V3.1 line database and MT CKD 2.5.2 continuum absorption model to calculate optical depth. Since line parameter databases have been updated and the continuum absorption may have large uncertainty, the purpose of this study is to assess the impact on {CH}4 retrieval from the choice of line parameter databases and the uncertainty of continuum absorption. We retrieved {CH}4 profiles with replacement of line parameter database from AER V3.1 to AER v1.0, HITRAN 2004, HITRAN 2008, AER V3.2, or HITRAN 2012 (Rothman et al. 2005, 2009, and 2013. Clough et al., 2005), we assumed 10% larger continuum absorption coefficients and 50% larger temperature dependent coefficient of continuum absorption based on the report by Paynter and Ramaswamy (2014). We compared the retrieved CH4 with the HIPPO CH4 observation (Wofsy et al., 2012). The difference from HIPPO observation of AER V3.2 was the smallest and 24.1 ± 45.9 ppbv. The differences of AER V1.0, HITRAN 2004, HITRAN 2008, and HITRAN 2012 were 35.6 ± 46.5 ppbv, 37.6 ± 46.3 ppbv, 32.1 ± 46.1 ppbv, and 35.2 ± 46.0 ppbv, respectively. Maximum {CH}4 retrieval differences were -0.4 ppbv at the layer of 314 hPa when we used 10% larger absorption coefficients of {H}2O foreign continuum. Comparing AER V3.2 case to HITRAN 2008 case, the line coupling effect reduced difference by 8.0 ppbv. Line coupling effects were important for GOSAT TIR {CH}4 retrieval. Effects from the uncertainty of continuum absorption were negligible small for GOSAT TIR CH4 retrieval.

Optimization of CO2 Surface Flux using GOSAT Total Column CO2: First Results for 2009-2010

NASA Astrophysics Data System (ADS)

Basu, S.; Houweling, S.

2011-12-01

Constraining surface flux estimates of CO2 using satellite measurements has been one of the long-standing goals of the atmospheric inverse modeling community. We present the first results of inverting GOSAT total column CO2 measurements for obtaining global monthly CO2 flux maps over one year (June 2009 to May 2010). We use the SRON RemoTeC retrieval of CO2 for our inversions. The SRON retrieval has been shown to have no bias when compared to TCCON total column measurements, and latitudinal gradients of the retrieved CO2 are consistent with gradients deduced from the surface flask network [Butz et al, 2011]. This makes this retrieval an ideal candidate for atmospheric inversions, which are highly sensitive to spurious gradients. Our inversion system is analogous to the CarbonTracker (CT) data assimilation system; it is initialized with the prior CO2 fluxes of CT, and uses the same atmospheric transport model, i.e., TM5. The two major differences are (a) we add GOSAT CO2 data to the inversion in addition to flask data, and (b) we use a 4DVAR optimization system instead of a Kalman filter. We compare inversions using (a) only GOSAT total column CO2 measurements, (b) only surface flask CO2 measurements, and (c) the joint data set of GOSAT and surface flask measurements. We validate GOSAT-only inversions against the NOAA surface flask network and joint inversions against CONTRAIL and other aircraft campaigns. We see that inverted fluxes from a GOSAT-only inversion are consistent with fluxes from a stations-only inversion, reaffirming the low biases in SRON retrievals. From the joint inversion, we estimate the amount of added constraints upon adding GOSAT total column measurements to existing surface layer measurements.

The performance of Yonsei CArbon Retrieval (YCAR) algorithm with improved aerosol information using GOSAT measurements over East Asia

NASA Astrophysics Data System (ADS)

Jung, Y.; Kim, J.; Kim, W.; Boesch, H.; Yoshida, Y.; Cho, C.; Lee, H.; Goo, T. Y.

2016-12-01

The Greenhouse Gases Observing SATellite (GOSAT) is the first satellite dedicated to measure atmospheric CO2 concentrations from space that can able to improve our knowledge about carbon cycle. Several studies have performed to develop the CO2 retrieval algorithms using GOSAT measurements, but limitations in spatial coverage and uncertainties due to aerosols and thin cirrus clouds are still remained as a problem for monitoring CO2 concentration globally. In this study, we develop the Yonsei CArbon Retrieval (YCAR) algorithm based on optimal estimation method to retrieve the column-averaged dry-air mole fraction of carbon dioxide (XCO2) with optimized a priori CO2 profiles and aerosol models over East Asia. In previous studies, the aerosol optical properties (AOP) and the aerosol top height used to cause significant errors in retrieved XCO2 up to 2.5 ppm. Since this bias comes from a rough assumption of aerosol information in the forward model used in CO2 retrieval process, the YCAR algorithm improves the process to take into account AOPs as well as aerosol vertical distribution; total AOD and the fine mode fraction (FMF) are obtained from the ground-based measurements closely located, and other parameters are obtained from a priori information. Comparing to ground-based XCO2 measurements, the YCAR XCO2 product has a bias of 0.59±0.48 ppm and 2.16±0.87 ppm at Saga and Tsukuba sites, respectively, showing lower biases and higher correlations rather than the GOSAT standard products. These results reveal that considering better aerosol information can improve the accuracy of CO2 retrieval algorithm and provide more useful XCO2 information with reduced uncertainties.

The validation of the Yonsei CArbon Retrieval algorithm with improved aerosol information using GOSAT measurements

NASA Astrophysics Data System (ADS)

Jung, Yeonjin; Kim, Jhoon; Kim, Woogyung; Boesch, Hartmut; Goo, Tae-Young; Cho, Chunho

2017-04-01

Although several CO2 retrieval algorithms have been developed to improve our understanding about carbon cycle, limitations in spatial coverage and uncertainties due to aerosols and thin cirrus clouds are still remained as a problem for monitoring CO2 concentration globally. Based on an optimal estimation method, the Yonsei CArbon Retrieval (YCAR) algorithm was developed to retrieve the column-averaged dry-air mole fraction of carbon dioxide (XCO2) using the Greenhouse Gases Observing SATellite (GOSAT) measurements with optimized a priori CO2 profiles and aerosol models over East Asia. In previous studies, the aerosol optical properties (AOP) are the most important factors in CO2 retrievals since AOPs are assumed as fixed parameters during retrieval process, resulting in significant XCO2 retrieval error up to 2.5 ppm. In this study, to reduce these errors caused by inaccurate aerosol optical information, the YCAR algorithm improved with taking into account aerosol optical properties as well as aerosol vertical distribution simultaneously. The CO2 retrievals with two difference aerosol approaches have been analyzed using the GOSAT spectra and have been evaluated throughout the comparison with collocated ground-based observations at several Total Carbon Column Observing Network (TCCON) sites. The improved YCAR algorithm has biases of 0.59±0.48 ppm and 2.16±0.87 ppm at Saga and Tsukuba sites, respectively, with smaller biases and higher correlation coefficients compared to the GOSAT operational algorithm. In addition, the XCO2 retrievals will be validated at other TCCON sites and error analysis will be evaluated. These results reveal that considering better aerosol information can improve the accuracy of CO2 retrieval algorithm and provide more useful XCO2 information with reduced uncertainties. This study would be expected to provide useful information in estimating carbon sources and sinks.

CO2 Annual and Semiannual Cycles from Satellite Retrievals and Models

NASA Astrophysics Data System (ADS)

Jiang, X.; Crisp, D.; Olsen, E. T.; Kulawik, S. S.; Miller, C. E.; Pagano, T. S.; Yung, Y. L.

2014-12-01

We have compared satellite CO2 retrievals from the Greenhouse gases Observing SATellite (GOSAT), Atmospheric Infrared Sounder (AIRS), and Tropospheric Emission Spectrometer (TES) with in-situ measurements from the Earth System Research Laboratory (NOAA-ESRL) Surface CO2 and Total Carbon Column Observing Network (TCCON), and utilized zonal means to characterize variability and distribution of CO2. In general, zonally averaged CO2 from the three satellite data sets are consistent with the surface and TCCON XCO2 data. Retrievals of CO2 from the three satellites show more (less) CO2 in the northern hemisphere than that in the southern hemisphere in the northern hemispheric winter (summer) season. The difference between the three satellite CO2 retrievals might be related to the different averaging kernels in the satellites CO2 retrievals. A multiple regression method was used to calculate the CO2 annual cycle and semiannual cycle amplitudes from different satellite CO2 retrievals. The CO2 annual cycle and semiannual cycle amplitudes are largest at the surface, as seen in the NOAA-ESRL CO2 data sets. The CO2 annual cycle and semiannual cycle amplitudes in the GOSAT XCO2, AIRS mid-tropospheric CO2, and TES mid-tropospheric CO2 are smaller compared with those from the surface CO2. Similar regression analysis was applied to the Model for OZone And Related chemical Tracers-2 (MOZART-2) and CarbonTracker model CO2. The convolved model CO2 annual cycle and semiannual cycle amplitudes are similar to those from the satellite CO2 retrievals, although the model tends to under-estimate the CO2 seasonal cycle amplitudes in the northern hemisphere mid-latitudes from the comparison with GOSAT and TES CO2 and underestimate the CO2 semi-annual cycle amplitudes in the high latitudes from the comparison with AIRS CO2. The difference between model and satellite CO2 can be used to identify possible deficiency in the model and improve the model in the future.

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.

Characterization of TANSO-FTS on GOSAT

NASA Astrophysics Data System (ADS)

Suto, H.; Kuze, A.; Kaneko, Y.; Hamazaki, T.

2006-12-01

In order to measure the global column concentration of carbon dioxide (CO2) and methane (CH4), the Green house gases Observing SATellite (GOSAT) will be planning to launch at August in 2008. To estimate and demonstrate the performance of TANSO-FTS (Thermal And Near infrared Sensor for carbon Observation Fourier-Transform Spectrometer) through the filed and laboratory experiments, the Bread Board Model (BBM) for TANSO-FTS has been developed. The BBM has three narrow bands detectable regions; 0.76, 1.6 and 2micrion (band1,2 and 3) with +/-2.5cm maximum optical path difference. The Signal to Noise ratio (SNR), response and the instrumental line shape (ILS) have been determined in the laboratory by introducing the light emitted from the black body, Ar lamp, and the tunable diode laser. The measured values of full width at half maximum (FWHM) are 0.35, 0.25, 0.24 cm-1 for band1, 2 and 3, respectively. Also, the measured ILS has good correlation with the calculated one, and the parameterization of off-axis effect has been investigated. The developed method will be applied to determine the characterization of Engineering Model (EM) and Proto Flight Model (PFM) of TANSO. In this presentation, the characterization of TANSO-BBM and the preliminary results of performance test as well as TANSO-EM will be reported.

Several thoughts for using new satellite remote sensing and global modeling for aerosol and cloud climate studies

NASA Astrophysics Data System (ADS)

Nakajima, Teruyuki; Hashimoto, Makiko; Takenaka, Hideaki; Goto, Daisuke; Oikawa, Eiji; Suzuki, Kentaroh; Uchida, Junya; Dai, Tie; Shi, Chong

2017-04-01

The rapid growth of satellite remote sensing technologies in the last two decades widened the utility of satellite data for understanding climate impacts of aerosols and clouds. The climate modeling community also has received the benefit of the earth observation and nowadays closed-collaboration of the two communities make us possible to challenge various applications for societal problems, such as for global warming and global-scale air pollution and others. I like to give several thoughts of new algorithm developments, model use of satellite data for climate impact studies and societal applications related with aerosols and clouds. Important issues are 1) Better aerosol detection and solar energy application using expanded observation ability of the third generation geostationary satellites, i.e. Himawari-8, GOES-R and future MTG, 2) Various observation functions by directional, polarimetric, and high resolution near-UV band by MISR, POLDER&PARASOL, GOSAT/CAI and future GOSAT2/CAI2, 3) Various applications of general purpose-imagers, MODIS, VIIRS and future GCOM-C/SGLI, and 4) Climate studies of aerosol and cloud stratification and convection with active and passive sensors, especially climate impact of BC aerosols using CLOUDSAT&CALIPSO and future Earth Explorer/EarthCARE.

New approaches to removing cloud shadows and evaluating the 380 nm surface reflectance for improved aerosol optical thickness retrievals from the GOSAT/TANSO-Cloud and Aerosol Imager

NASA Astrophysics Data System (ADS)

Fukuda, Satoru; Nakajima, Teruyuki; Takenaka, Hideaki; Higurashi, Akiko; Kikuchi, Nobuyuki; Nakajima, Takashi Y.; Ishida, Haruma

2013-12-01

satellite aerosol retrieval algorithm was developed to utilize a near-ultraviolet band of the Greenhouse gases Observing SATellite/Thermal And Near infrared Sensor for carbon Observation (GOSAT/TANSO)-Cloud and Aerosol Imager (CAI). At near-ultraviolet wavelengths, the surface reflectance over land is smaller than that at visible wavelengths. Therefore, it is thought possible to reduce retrieval error by using the near-ultraviolet spectral region. In the present study, we first developed a cloud shadow detection algorithm that uses first and second minimum reflectances of 380 nm and 680 nm based on the difference in Rayleigh scattering contribution for these two bands. Then, we developed a new surface reflectance correction algorithm, the modified Kaufman method, which uses minimum reflectance data at 680 nm and the NDVI to estimate the surface reflectance at 380 nm. This algorithm was found to be particularly effective at reducing the aerosol effect remaining in the 380 nm minimum reflectance; this effect has previously proven difficult to remove owing to the infrequent sampling rate associated with the three-day recursion period of GOSAT and the narrow CAI swath of 1000 km. Finally, we applied these two algorithms to retrieve aerosol optical thicknesses over a land area. Our results exhibited better agreement with sun-sky radiometer observations than results obtained using a simple surface reflectance correction technique using minimum radiances.

Assessment of Global Carbon Dioxide Concentration Using MODIS and GOSAT Data

PubMed Central

Guo, Meng; Wang, Xiufeng; Li, Jing; Yi, Kunpeng; Zhong, Guosheng; Tani, Hiroshi

2012-01-01

Carbon dioxide (CO2) is the most important greenhouse gas (GHG) in the atmosphere and is the greatest contributor to global warming. CO2 concentration data are usually obtained from ground observation stations or from a small number of satellites. Because of the limited number of observations and the short time series of satellite data, it is difficult to monitor CO2 concentrations on regional or global scales for a long time. The use of the remote sensing data such as the Advanced Very High Resolution Radiometer (AVHRR) or Moderate Resolution Imaging Spectroradiometer (MODIS) data can overcome these problems, particularly in areas with low densities of CO2 concentration watch stations. A model based on temperature (MOD11C3), vegetation cover (MOD13C2 and MOD15A2) and productivity (MOD17A2) of MODIS (which we have named the TVP model) was developed in the current study to assess CO2 concentrations on a global scale. We assumed that CO2 concentration from the Thermal And Near infrared Sensor for carbon Observation (TANSO) aboard the Greenhouse gases Observing SATellite (GOSAT) are the true values and we used these values to check the TVP model accuracy. The results indicate that the accuracy of the TVP model is different in different continents: the greatest Pearson’s correlation coefficient (R2) was 0.75 in Eurasia (RMSE = 1.16) and South America (RMSE = 1.17); the lowest R2 was 0.57 in Australia (RMSE = 0.73). Compared with the TANSO-observed CO2 concentration (XCO2), we found that the accuracy throughout the World is between −2.56∼3.14 ppm. Potential sources of TVP model uncertainties were also analyzed and identified. PMID:23443383

Assessment of global carbon dioxide concentration using MODIS and GOSAT data.

PubMed

Guo, Meng; Wang, Xiufeng; Li, Jing; Yi, Kunpeng; Zhong, Guosheng; Tani, Hiroshi

2012-11-26

Carbon dioxide (CO(2)) is the most important greenhouse gas (GHG) in the atmosphere and is the greatest contributor to global warming. CO(2) concentration data are usually obtained from ground observation stations or from a small number of satellites. Because of the limited number of observations and the short time series of satellite data, it is difficult to monitor CO(2) concentrations on regional or global scales for a long time. The use of the remote sensing data such as the Advanced Very High Resolution Radiometer (AVHRR) or Moderate Resolution Imaging Spectroradiometer (MODIS) data can overcome these problems, particularly in areas with low densities of CO(2) concentration watch stations. A model based on temperature (MOD11C3), vegetation cover (MOD13C2 and MOD15A2) and productivity (MOD17A2) of MODIS (which we have named the TVP model) was developed in the current study to assess CO(2) concentrations on a global scale. We assumed that CO(2) concentration from the Thermal And Near infrared Sensor for carbon Observation (TANSO) aboard the Greenhouse gases Observing SATellite (GOSAT) are the true values and we used these values to check the TVP model accuracy. The results indicate that the accuracy of the TVP model is different in different continents: the greatest Pearson's correlation coefficient (R2) was 0.75 in Eurasia (RMSE = 1.16) and South America (RMSE = 1.17); the lowest R2 was 0.57 in Australia (RMSE = 0.73). Compared with the TANSO-observed CO(2) concentration (XCO(2)), we found that the accuracy throughout the World is between -2.56~3.14 ppm. Potential sources of TVP model uncertainties were also analyzed and identified.

Atmospheric CH4 and CO2 enhancements and biomass burning emission ratios derived from satellite observations of the 2015 Indonesian fire plumes

NASA Astrophysics Data System (ADS)

Parker, Robert J.; Boesch, Hartmut; Wooster, Martin J.; Moore, David P.; Webb, Alex J.; Gaveau, David; Murdiyarso, Daniel

2016-08-01

The 2015-2016 strong El Niño event has had a dramatic impact on the amount of Indonesian biomass burning, with the El Niño-driven drought further desiccating the already-drier-than-normal landscapes that are the result of decades of peatland draining, widespread deforestation, anthropogenically driven forest degradation and previous large fire events. It is expected that the 2015-2016 Indonesian fires will have emitted globally significant quantities of greenhouse gases (GHGs) to the atmosphere, as did previous El Niño-driven fires in the region. The form which the carbon released from the combustion of the vegetation and peat soils takes has a strong bearing on its atmospheric chemistry and climatological impacts. Typically, burning in tropical forests and especially in peatlands is expected to involve a much higher proportion of smouldering combustion than the more flaming-characterised fires that occur in fine-fuel-dominated environments such as grasslands, consequently producing significantly more CH4 (and CO) per unit of fuel burned. However, currently there have been no aircraft campaigns sampling Indonesian fire plumes, and very few ground-based field campaigns (none during El Niño), so our understanding of the large-scale chemical composition of these extremely significant fire plumes is surprisingly poor compared to, for example, those of southern Africa or the Amazon.Here, for the first time, we use satellite observations of CH4 and CO2 from the Greenhouse gases Observing SATellite (GOSAT) made in large-scale plumes from the 2015 El Niño-driven Indonesian fires to probe aspects of their chemical composition. We demonstrate significant modifications in the concentration of these species in the regional atmosphere around Indonesia, due to the fire emissions.Using CO and fire radiative power (FRP) data from the Copernicus Atmosphere Service, we identify fire-affected GOSAT soundings and show that peaks in fire activity are followed by subsequent large

Progress of Validation of GOSAT Standard Products

NASA Astrophysics Data System (ADS)

Uchino, Osamu

2010-05-01

Isamu Morino, Tomoaki Tanaka, Yuki Miyamoto, Yukio Yoshida, Tatsuya Yokota, Toshinobu Machida National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan Debra Wunch, Paul Wennberg Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, USA Geoffrey Toon Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA Thorsten Warneke, Justus Notholt Institute of Environmental Physics, University of Bremen, Bremen, Germany David Griffith, Nicholas Deutscher Department of Chemistry, University of Wollongong, Wollongong New South Wales, Australia Vanessa Sherlock National Institute of Water and Atmospheric Research, Lauder, Central Otago, New Zealand Hidekazu Matsueda, Yousuke Sawa Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki 305-0052, Japan Colm Sweeney, Pieter Tans Earth System Research Laboratory, NOAA, Boulder, USA The Greenhouse gases Observing SATellite (GOSAT), launched on 23 January 2009, is the world's first satellite dedicated to measuring the concentrations of the two major greenhouse gases, carbon dioxide (CO2) and methane (CH4), from space. The data measured with the Thermal And Near-infrared Sensor for carbon Observation Fourier Transform Spectrometer (TANSO-FTS) and the Cloud and Aerosol Imager (TANSO-CAI) are processed into several types of data products. Column abundances of CO2 and CH4 (TANSO-FTS SWIR L2 data product) are retrieved from the FTS L1B spectral data. Validation of the FTS Level 2 data product is critical since the data is used for generating the FTS Level 3 (global distributions of column-averaged mixing ratio data of XCO2 and XCH4) and the FTS Level 4 (regional CO2 fluxes and three dimensional distribution of CO2 calculated from the estimated fluxes) products. The reference data to be used for validating abundances are required to have uncertainties of less than 1.0 % (0.3 % or 1 ppm is desirable) for CO2 and 2.0 % for CH4. Ground

Information content analysis: the potential for methane isotopologue retrieval from GOSAT-2

NASA Astrophysics Data System (ADS)

Malina, Edward; Yoshida, Yukio; Matsunaga, Tsuneo; Muller, Jan-Peter

2018-02-01

Atmospheric methane is comprised of multiple isotopic molecules, with the most abundant being 12CH4 and 13CH4, making up 98 and 1.1 % of atmospheric methane respectively. It has been shown that is it possible to distinguish between sources of methane (biogenic methane, e.g. marshland, or abiogenic methane, e.g. fracking) via a ratio of these main methane isotopologues, otherwise known as the δ13C value. δ13C values typically range between -10 and -80 ‰, with abiogenic sources closer to zero and biogenic sources showing more negative values. Initially, we suggest that a δ13C difference of 10 ‰ is sufficient, in order to differentiate between methane source types, based on this we derive that a precision of 0.2 ppbv on 13CH4 retrievals may achieve the target δ13C variance. Using an application of the well-established information content analysis (ICA) technique for assumed clear-sky conditions, this paper shows that using a combination of the shortwave infrared (SWIR) bands on the planned Greenhouse gases Observing SATellite (GOSAT-2) mission, 13CH4 can be measured with sufficient information content to a precision of between 0.7 and 1.2 ppbv from a single sounding (assuming a total column average value of 19.14 ppbv), which can then be reduced to the target precision through spatial and temporal averaging techniques. We therefore suggest that GOSAT-2 can be used to differentiate between methane source types. We find that large unconstrained covariance matrices are required in order to achieve sufficient information content, while the solar zenith angle has limited impact on the information content.

Space-based observations of megacity carbon dioxide

NASA Astrophysics Data System (ADS)

Kort, Eric A.; Frankenberg, Christian; Miller, Charles E.; Oda, Tom

2012-09-01

Urban areas now house more than half the world's population, and are estimated to contribute over 70% of global energy-related CO2 emissions. Many cities have emission reduction policies in place, but lack objective, observation-based methods for verifying their outcomes. Here we demonstrate the potential of satellite-borne instruments to provide accurate global monitoring of megacity CO2 emissions using GOSAT observations of column averaged CO2 dry air mole fraction (XCO2) collected over Los Angeles and Mumbai. By differencing observations over the megacity with those in nearby background, we observe robust, statistically significant XCO2 enhancements of 3.2 ± 1.5 ppm for Los Angeles and 2.4 ± 1.2 ppm for Mumbai, and find these enhancements can be exploited to track anthropogenic emission trends over time. We estimate that XCO2 changes as small as 0.7 ppm in Los Angeles, corresponding to a 22% change in emissions, could be detected with GOSAT at the 95% confidence level.

The Potential for Methane Isotopologue Channels in GOSAT-2

NASA Astrophysics Data System (ADS)

Malina, Edward; Yoshida, Yukio; Matsunaga, Tsuneo; Muller, Jan-Peter

2017-04-01

Of the major Greenhouse Gases (GHGs) currently considered as having a major impact on atmospheric chemistry, Methane is amongst the most important (IPCC, 2014). Methane concentration in the atmosphere has been documented to be rising steadily over the past century, aside from an unexplained short period in the middle of the last decade (Heimann., 2011), leading to renewed efforts to understand global atmospheric Methane. Atmospheric Methane is primarily composed of two key isotopologues, 12CH4 and 13CH4, which have a natural abundance of about 98% and 1.1% respectively. It is a well-established fact that different sources of Methane (i.e. biogenic sources such as methanogens, or non-biogenic such as industrial hydrocarbon burning) vary in the abundance of these isotopologues (Etiope, 2009). The global identification of the ratios of these isotopologues could vastly increase knowledge of global Methane sources, and shed some light on global Methane growth. GOSAT-2 due to be launched in 2018 is a follow on from the original GOSAT mission launched in 2009. GOSAT-2 aims to continue the legacy of GOSAT by providing global measurements of Methane and Carbon Dioxide on a global basis in order to monitor GHG emissions. GOSAT-2 in the context of this study has a significant advantage over GOSAT, which is the extension of the sensitivity of band 3 to 2330nm from 2080nm where significant numbers of Methane spectral lines are located. In this study we apply the well-established Information Content (IC) analysis techniques originally proposed by Rodgers (2000) to determine the potential benefit of retrieving total column Methane isotopologue concentrations assuming bands 2 and 3 of the GOSAT-2/TANSO-FTS-2 instrument. The value of such studies has been proven on multiple occasions and can provide guidance on appropriate potential retrieval setups. Due to the fact that there has been limited research in this area, no 'a priori' state vectors or Variance Covariance Matrices (VCMs

Global distribution of methane emissions, emission trends, and OH trends inferred from an inversion of GOSAT data for 2010-2015

NASA Astrophysics Data System (ADS)

Maasakkers, J. D.; Jacob, D.; Payer Sulprizio, M.; Hersher, M.; Scarpelli, T.; Turner, A. J.; Sheng, J.; Bloom, A. A.; Bowman, K. W.; Parker, R.

2017-12-01

We present a global inversion of methane sources and sinks using GOSAT satellite data from 2010 up to 2015. The inversion optimizes emissions and their trends at 4° × 5° resolution as well as the interannual variability of global OH concentrations. It uses an analytical approach that quantifies the information content from the GOSAT observations and provides full error characterization. We show how the analytical approach can be applied in log-space, ensuring the positivity of the posterior. The inversion starts from state-of-science a priori emission inventories including the Gridded EPA inventory for US anthropogenic emissions, detailed oil and gas emissions for Canada and Mexico, EDGAR v4.3.2 for anthropogenic emissions in other countries, the WetCHARTs product for wetlands, and our own estimates for geological seeps. Inversion results show lower emissions over Western Europe and China than predicted by EDGAR v4.3.2 but higher emissions over Japan. In contrast to previous inversions that used incorrect patterns in a priori emissions, we find that the EPA inventory does not underestimate US anthropogenic emissions. Results for trends show increasing emissions in the tropics combined with decreasing emissions in Europe, and a decline in OH concentrations contributing to the global methane trend.

Satellite-derived SIF and CO2 Observations Show Coherent Responses to Interannual Climate Variations

NASA Astrophysics Data System (ADS)

Butterfield, Z.; Hogikyan, A.; Kulawik, S. S.; Keppel-Aleks, G.

2017-12-01

Gross primary production (GPP) is the single largest carbon flux in the Earth system, but its sensitivity to changes in climate is subject to significant uncertainty. Satellite measurements of solar-induced chlorophyll fluorescence (SIF) offer insight into spatial and temporal patterns in GPP at a global scale and, combined with other satellite-derived datasets, provide unprecedented opportunity to explore interactions between atmospheric CO2, GPP, and climate variability. To explore potential drivers of GPP in the Northern Hemisphere (NH), we compare monthly-averaged SIF data from the Global Ozone Monitoring Experiment 2 (GOME-2) with observed anomalies in temperature (T; CRU-TS), liquid water equivalent (LWE) from the Gravity Recovery and Climate Experiment (GRACE), and photosynthetically active radiation (PAR; CERES SYN1deg). Using observations from 2007 through 2015 for several NH regions, we calculate month-specific sensitivities of SIF to variability in T, LWE, and PAR. These sensitivities provide insight into the seasonal progression of how productivity is affected by climate variability and can be used to effectively model the observed SIF signal. In general, we find that high temperatures are beneficial to productivity in the spring, but detrimental in the summer. The influences of PAR and LWE are more heterogeneous between regions; for example, higher LWE in North American temperate forest leads to decreased springtime productivity, while exhibiting a contrasting effect in water-limited regions. Lastly, we assess the influence of variations in terrestrial productivity on atmospheric carbon using a new lower tropospheric CO2 product derived from the Greenhouse Gases Observing Satellite (GOSAT). Together, these data shed light on the drivers of interannual variability in the annual cycle of NH atmospheric CO2, and may provide improved constraints on projections of long-term carbon cycle responses to climate change.

Preliminary verification for application of a support vector machine-based cloud detection method to GOSAT-2 CAI-2

NASA Astrophysics Data System (ADS)

Oishi, Yu; Ishida, Haruma; Nakajima, Takashi Y.; Nakamura, Ryosuke; Matsunaga, Tsuneo

2018-05-01

The Greenhouse Gases Observing Satellite (GOSAT) was launched in 2009 to measure global atmospheric CO2 and CH4 concentrations. GOSAT is equipped with two sensors: the Thermal And Near infrared Sensor for carbon Observations (TANSO)-Fourier transform spectrometer (FTS) and TANSO-Cloud and Aerosol Imager (CAI). The presence of clouds in the instantaneous field of view of the FTS leads to incorrect estimates of the concentrations. Thus, the FTS data suspected to have cloud contamination must be identified by a CAI cloud discrimination algorithm and rejected. Conversely, overestimating clouds reduces the amount of FTS data that can be used to estimate greenhouse gas concentrations. This is a serious problem in tropical rainforest regions, such as the Amazon, where the amount of useable FTS data is small because of cloud cover. Preparations are continuing for the launch of the GOSAT-2 in fiscal year 2018. To improve the accuracy of the estimates of greenhouse gases concentrations, we need to refine the existing CAI cloud discrimination algorithm: Cloud and Aerosol Unbiased Decision Intellectual Algorithm (CLAUDIA1). A new cloud discrimination algorithm using a support vector machine (CLAUDIA3) was developed and presented in another paper. Although the use of visual inspection of clouds as a standard for judging is not practical for screening a full satellite data set, it has the advantage of allowing for locally optimized thresholds, while CLAUDIA1 and -3 use common global thresholds. Thus, the accuracy of visual inspection is better than that of these algorithms in most regions, with the exception of snow- and ice-covered surfaces, where there is not enough spectral contrast to identify cloud. In other words, visual inspection results can be used as truth data for accuracy evaluation of CLAUDIA1 and -3. For this reason visual inspection can be used for the truth metric for the cloud discrimination verification exercise. In this study, we compared CLAUDIA1-CAI and

Using airborne HIAPER Pole-to-Pole Observations (HIPPO) to evaluate model and remote sensing estimates of atmospheric carbon dioxide

NASA Astrophysics Data System (ADS)

Frankenberg, Christian; Kulawik, Susan S.; Wofsy, Steven C.; Chevallier, Frédéric; Daube, Bruce; Kort, Eric A.; O'Dell, Christopher; Olsen, Edward T.; Osterman, Gregory

2016-06-01

In recent years, space-borne observations of atmospheric carbon dioxide (CO2) have been increasingly used in global carbon-cycle studies. In order to obtain added value from space-borne measurements, they have to suffice stringent accuracy and precision requirements, with the latter being less crucial as it can be reduced by just enhanced sample size. Validation of CO2 column-averaged dry air mole fractions (XCO2) heavily relies on measurements of the Total Carbon Column Observing Network (TCCON). Owing to the sparseness of the network and the requirements imposed on space-based measurements, independent additional validation is highly valuable. Here, we use observations from the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) flights from 01/2009 through 09/2011 to validate CO2 measurements from satellites (Greenhouse Gases Observing Satellite - GOSAT, Thermal Emission Sounder - TES, Atmospheric Infrared Sounder - AIRS) and atmospheric inversion models (CarbonTracker CT2013B, Monitoring Atmospheric Composition and Climate (MACC) v13r1). We find that the atmospheric models capture the XCO2 variability observed in HIPPO flights very well, with correlation coefficients (r2) of 0.93 and 0.95 for CT2013B and MACC, respectively. Some larger discrepancies can be observed in profile comparisons at higher latitudes, in particular at 300 hPa during the peaks of either carbon uptake or release. These deviations can be up to 4 ppm and hint at misrepresentation of vertical transport. Comparisons with the GOSAT satellite are of comparable quality, with an r2 of 0.85, a mean bias μ of -0.06 ppm, and a standard deviation σ of 0.45 ppm. TES exhibits an r2 of 0.75, μ of 0.34 ppm, and σ of 1.13 ppm. For AIRS, we find an r2 of 0.37, μ of 1.11 ppm, and σ of 1.46 ppm, with latitude-dependent biases. For these comparisons at least 6, 20, and 50 atmospheric soundings have been averaged for GOSAT, TES, and AIRS

Comparison of several satellite-derived Sun-Induced Fluorescence products

NASA Astrophysics Data System (ADS)

Bacour, C.; Maignan, F.; MacBean, N.; Köhler, P.; Vountas, M.; Khosravi, N.; Guanter, L.; Joiner, J.; Frankenberg, C.; Somkuti, P.; Peylin, P.

2017-12-01

Large uncertainties remain in our representation of the global carbon budget, in particular regarding the spatial and temporal dynamics of the net land surface CO2 fluxes along with its two constitutive components, photosynthesis and respiration. Bolstered by the evidenced linear relationship between remotely sensed sun-induced fluorescence (SIF) and plant gross carbon uptake (GPP - gross primary productivity) at broad spatial and temporal scales, satellite SIF products are foreseen to provide significant constraint on one of the key component of the terrestrial carbon cycle, and ultimately to help reducing the uncertainties in the projections of the fate of carbon sinks and sources under a changing climate.Global SIF estimates are now "routinely" produced from observations of space-borne spectrometers having sufficient spectral resolution/sampling in solar Fraunhofer lines or atmospheric absorption bands in the visible - near-infrared domain. Differences between SIF products derived from different instruments are expected depending on evaluated wavelengths (SIF has a spectral signature with maxima around 685 and 740 nm) and their own observation characteristics (time of satellite overpass, spatial resolution, revisit frequency, spectral resolution, etc.). For instance, SIF products estimated at 760 nm (GOSAT, OCO-2) are about 1.5 times lower than estimates at 740 nm (GOME-2, SCIAMACHY). However, as highlighted by Köhler et al. (2015), strong discrepancies in SIF absolute values may arise for products derived from the same set of observations (GOME-2) but using different estimation algorithms. In the view of using satellite SIF products to calibrate terrestrial biosphere models (e.g. through data assimilation), this is highly problematic, especially for evergreen ecosystems where SIF magnitude is the only observational constraint that can be made use of.In this study, we compare several gridded satellite SIF products and quantify their similarities

Regional uncertainty of GOSAT XCO2 retrievals in China: quantification and attribution

NASA Astrophysics Data System (ADS)

Bie, Nian; Lei, Liping; Zeng, ZhaoCheng; Cai, Bofeng; Yang, Shaoyuan; He, Zhonghua; Wu, Changjiang; Nassar, Ray

2018-03-01

The regional uncertainty of the column-averaged dry air mole fraction of CO2 (XCO2) retrieved using different algorithms from the Greenhouse gases Observing SATellite (GOSAT) and its attribution are still not well understood. This paper investigates the regional performance of XCO2 within a latitude band of 37-42° N segmented into 8 cells in a grid of 5° from west to east (80-120° E) in China, where typical land surface types and geographic conditions exist. The former includes desert, grassland and built-up areas mixed with cropland; and the latter includes anthropogenic emissions that change from small to large from west to east, including those from the megacity of Beijing. For these specific cells, we evaluate the regional uncertainty of GOSAT XCO2 retrievals by quantifying and attributing the consistency of XCO2 retrievals from four algorithms (ACOS, NIES, OCFP and SRFP) by intercomparison. These retrievals are then specifically compared with simulated XCO2 from the high-resolution nested model in East Asia of the Goddard Earth Observing System 3-D chemical transport model (GEOS-Chem). We also introduce the anthropogenic CO2 emissions data generated from the investigation of surface emitting point sources that was conducted by the Ministry of Environmental Protection of China to GEOS-Chem simulations of XCO2 over the Chinese mainland. The results indicate that (1) regionally, the four algorithms demonstrate smaller absolute biases of 0.7-1.1 ppm in eastern cells, which are covered by built-up areas mixed with cropland with intensive anthropogenic emissions, than those in the western desert cells (1.0-1.6 ppm) with a high-brightness surface from the pairwise comparison results of XCO2 retrievals. (2) Compared with XCO2 simulated by GEOS-Chem (GEOS-XCO2), the XCO2 values from ACOS and SRFP have better agreement, while values from OCFP are the least consistent with GEOS-XCO2. (3) Viewing attributions of XCO2 in the spatio-temporal pattern, ACOS and SRFP

Characteristics of Four-years of GOSAT/TANSO-FTS TIR V1.0 CO2 and CH4 Products

NASA Astrophysics Data System (ADS)

Saitoh, N.; Kimoto, S.; Sugimura, R.; Imasu, R.; Shiomi, K.; Kuze, A.; Kataoka, F.; Knuteson, R. O.; Machida, T.; Sawa, Y.; Matsuda, H.

2015-12-01

Greenhouse Gases Observing Satellite (GOSAT) was launched on 23 January 2009, and has continued to make global observations, including both nadir and off-nadir measurements, for more than six years since its launch. The thermal infrared (TIR) band of Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) on board the GOSAT has observed CO2 and CH4 profiles. We have analyzed the four-year data from 2010 through 2013 of the latest released version of the TIR Level 2 (L2) CO2 and CH4 products (V1.0). Comparisons of the TIR upper atmospheric CO2 product with CO2 data from Comprehensive Observation Network for Trace Gases by Airliner (CONTRAIL) aircraft measurements show that the growth rate estimated from the TIR CO2 data is slightly lower than that from the CONTRAIL data. Overall, the TIR V1.0 CO2 product has better quality in the upper troposphere and lower stratosphere than the a priori judging from comparisons with the collocated aircraft data. In spring and summer, however, the quality of the TIR L2 CO2 products became slightly worse than in the other seasons, especially in the low and northern-mid latitudes. This is because the corresponding a priori had a larger bias and the TIR Level 1B (L1B) radiance spectra might have a larger bias in the spring-summer seasons. Here, we have tested several types of correction methods to modify the L1B spectral bias, and then compared CO2 and CH4 concentrations retrieved after applying spectral bias correction factors with coincident CONTRAIL and HIAPER Pole-to-Pole Observation (HIPPO) aircraft data. The comparison results suggest that the L1B spectral bias correction factor should be changed depending on wavelength. In addition, it should be expressed as a function of on-board internal calibration blackbody temperatures. This is because they are weak season-dependent parameters; they were clearly lower in spring and summer.

Angular Normalization of Ground and Satellite Observations of Sun-induced Chlorophyll Fluorescence for Assessing Vegetation Productivity

NASA Astrophysics Data System (ADS)

Chen, J. M.; He, L.; Chou, S.; Ju, W.; Zhang, Y.; Joiner, J.; Liu, J.; Mo, G.

2017-12-01

Sun-induced chlorophyll fluorescence (SIF) measured from plant canopies originates mostly from sunlit leaves. Observations of SIF by satellite sensors, such as GOME-2 and GOSAT, are often made over large view zenith angle ranges, causing large changes in the viewed sunlit leaf fraction across the scanning swath. Although observations made by OCO-2 are near nadir, the observed sunlit leaf fraction could still vary greatly due to changes in the solar zenith angle with latitude and time of overpass. To demonstrate the importance of considering the satellite-target-view geometry in using SIF for assessing vegetation productivity, we conducted multi-angle measurements of SIF using a hyperspectral sensor mounted on an automated rotating system over a rice field near Nanjing, China. A method is developed to separate SIF measurements at each angle into sunlit and shaded leaf components, and an angularly normalized canopy-level SIF is obtained as the weighted sum of sunlit and shaded SIF. This normalized SIF is shown to be a much better proxy of GPP of the rice field measured by an eddy covariance system than the unnormalized SIF observations. The same normalization scheme is also applied to the far-red GOME-2 SIF observations on sunny days, and we found that the normalized SIF is better correlated with model-simulated GPP than the original SIF observations. The coefficient of determination (R2) is improved by 0.07±0.04 on global average using the normalization scheme. The most significant improvement in R2 by 0.09±0.04 is found in deciduous broadleaf forests, where the observed sunlit leaf fraction is highly sensitive to solar zenith angle.

Validation of GOSAT/TANSO-FTS TIR V01.00 CO2 and CH4 products

NASA Astrophysics Data System (ADS)

Saitoh, N.; Kimoto, S.; Sugimura, R.; Imasu, R.; Kawakami, S.; Shiomi, K.; Machida, T.; Sawa, Y.; Matsuda, H.

2014-12-01

Greenhouse Gases Observing Satellite (GOSAT) has been making observations continuously for more than five years since its launch on 23 January 2009. Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) on board the GOSAT simultaneously observes column abundances and profiles of CO2 and CH4 in the same field of view, from the shortwave infrared (SWIR) and thermal infrared (TIR) bands, respectively. We have just released the latest TIR CO2 and CH4 products, V01.00, to registered researchers. To validate the data quality of the V01.00 TIR CO2 product, we compared the TIR data with CO2 data obtained by Continuous CO2 Measuring Equipment (CME) on board JAL aircraft in Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) project. The aircraft CO2 data obtained during the level flights were compared with the V01.00 TIR upper tropospheric CO2 data. The CONTRAIL CO2 "profile" data obtained during the ascending and descending flights over several airports were compared with the TIR CO2 profiles. In the profile comparisons, we applied the TIR averaging kernel functions to the coincident CONTRAIL CO2 profiles. The V01.00 upper atmospheric CO2 data agreed to the CONTRAIL level flight CO2 data on average within 0.5-1%. Some TIR CO2 data showed relatively large differences from the nearest aircraft data, which suggests the existence of several problems such as L1B spectral calibration and nighttime cloud detection issues. The TIR V01.00 CO2 profile data from 9 to 13 km showed better agreement to CONTRAIL CO2 data than the a priori. However, the TIR CO2 data at around and below 5 km had low bias of 1-1.5%. The TIR V01.00 CH4 data generally showed reasonable latitudinal distributions as the previous version. In the Antarctic, unexpected high amounts of CH4 were seen in upper troposphere and lower stratosphere in autumn. This is probably because of the problem of simultaneously retrieved ozone concentration.

Data Dissemination System Status and Plan for Jaxa's Earth Observation Satellite Data

NASA Astrophysics Data System (ADS)

Fuda, M.; Miura, S.

2012-12-01

1. INTRODUCTION JAXA is Japan's national aerospace agency and responsible for research, technology development and the launch of satellites into orbit, and is involved in many more advanced missions, such as asteroid exploration and possible manned exploration of the Moon. Since 1978, JAXA started to disseminate earth observation data acquired by satellites to researchers and those data scene became more than two Million scenes in 2011. This paper focuses on the status and future plan for JAXA's Data Dissemination System for those data. 2. STATUS JAXA is Japan's national aerospace agency and responsible for research, technology development and the launch of satellites into orbit. In October 1978, JAXA opened the Earth Observation Center (EOC) and started to archive and disseminate earth observation data acquired by multiple satellites. 2.1. Target data Currently, the disseminated data includes "JAXA's satellite/sensor data" and "non-JAXA's satellite/sensor data", as shown in Table 2-1. In 2011, the total disseminated data scene became more than two Million scenes. 2.2. Data Dissemination Guideline The JAXA basic data dissemination guideline is a free for researchers and specific agencies. JAXA has two approaches for dissemination. One is that the data is distributed for specific agencies by Mission Operation Systems (MOS). Each project has its own MOS, for example, GCOM-W1 has a GCOM-W1 MOS. Another is that the data is disseminated for many researchers by Data Distribution Systems. Now JAXA has three Data Distribution systems, EOIS, AUIG and GCOM-W1DPSS. Table 2-1 : Disseminated earth observation data from JAXA's facility Satellite Sensor Processing Level ALOS AVNIR-2 Level 1 PRISM Level 1 PALSAR Level 1 TRMM PR Level 1, 2, 3 CMB Level 1, 2, 3 TMI Level 1, 2, 3 VIR Level 1, 2, 3 Aqua AMSR-E Level 1, 2, 3 ADEOS-II AMSR Level 1, 2, 3 GLI-1km Level 1, 2, 3 GLI-250m Level 1, 2, 3 JERS-1 OSW Level 0, 1, 2 OVN Level 0, 1, 2, 5 SAR Level 1, 2 ADEOS AVNIR Level 1 OCTS

An 8-year, high-resolution reanalysis of atmospheric carbon dioxide mixing ratios based on OCO-2 and GOSAT-ACOS retrievals

NASA Astrophysics Data System (ADS)

Weir, B.; Chatterjee, A.; Ott, L. E.; Pawson, S.

2017-12-01

This talk presents an overview of results from the GEOS-Carb reanalysis of retrievals of average-column carbon dioxide (XCO2) from the Orbiting Carbon Observatory 2 (OCO-2) and Greenhouse Gases Observing Satellite (GOSAT) satellite missions. The reanalysis is a Level 3 (L3) product: a collection of 3D fields of carbon dioxide (CO2) mixing ratios every 6 hours beginning in April 2009 going until the present on a grid with a 0.5 degree horizontal resolution and 72 vertical levels from the surface to 0.01 hPa. Using an assimilation methodology based on the Goddard Earth Observing System (GEOS) atmospheric data assimilation system (ADAS), the L3 fields are weighted averages of the two satellite retrievals and predictions from the GEOS general circulation model driven by assimilated meteorology from the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). In places and times where there are a dense number of soundings, the observations dominate the predicted mixing ratios, while the model is used to fill in locations with fewer soundings, e.g., high latitudes and the Amazon. Blending the satellite observations with model predictions has at least two notable benefits. First, it provides a bridge for evaluating the satellite retrievals and their uncertainties against a heterogeneous collection of observations including those from surface sites, towers, aircraft, and soundings from the Total Carbon Column Observing Network (TCCON). Extensive evaluations of the L3 reanalysis clearly demonstrate both the strength and the deficiency of the satellite retrievals. Second, it is possible to estimate variables from the reanalysis without introducing bias due to spatiotemporal variability in sounding coverage. For example, the assimilated product provides robust estimates of the monthly CO2 global growth rate. These monthly growth rate estimates show significant differences from estimates based on in situ observations, which have sparse coverage

GOSAT and OCO-2 Inter-comparison on Measured Spectral Radiance and Retrieved Carbon Dioxide

NASA Astrophysics Data System (ADS)

Kataoka, F.; Kuze, A.; Shiomi, K.; Suto, H.; Crisp, D.; Bruegge, C. J.; Schwandner, F. M.

2016-12-01

TANSO-FTS onboard GOSAT and grating spectrometer on OCO-2 use different measurement techniques to measure carbon dioxide (CO2) and molecular oxygen (O2). Both instruments observe sunlight reflected from the Earth's surface in almost the same spectral range. As a first step in cross calibrating these two instruments, we compared spectral radiance observations within the three short wave infrared (SWIR) spectral bands centered on the O2 A-band (O2A), the weak CO2 band near 1.6 microns (Weak-CO2) and 2.06 micons (Strong-CO2) bands at temporally coincident and spatially collocated points. In this work, we reconciled the different size of the footprints and evaluated at various types of surface targets such as ocean, desert and forest. For radiometric inter-comparisons, we consider long term instrument sensitivity degradation in orbit and differences in viewing geometry and associated differences in surface bidirectional reflectance distribution function (BRDF). Measured spectral radiances agree very well within 5% for all bands. This presentation will summarize these comparisons of GOSAT and OCO-2 spectral radiance observations and associated estimates of carbon dioxide and related parameters retrieved with the same algorithm at matchup points. We will also discuss instrument related uncertainties from various target observations.

Testing forward model against OCO-2 and TANSO-FTS/GOSAT observed spectra in near infrared range

NASA Astrophysics Data System (ADS)

Zadvornykh, Ilya V.; Gribanov, Konstantin G.

2015-11-01

An existing software package FIRE-ARMS (Fine InfraRed Explorer for Atmospheric Remote MeasurementS) was modified by embedding vector radiative transfer model VLIDORT. Thus the program tool includes both thermal (TIR) and near infrared (NIR) regions. We performed forward simulation of near infrared spectra on the top of the atmosphere for outgoing radiation accounting multiple scattering in cloudless atmosphere. Simulated spectra are compared with spectra measured by TANSO-FTS/GOSAT and OCO-2 in the condition of cloudless atmosphere over Western Siberia. NCEP/NCAR reanalysis data were used to complete model atmosphere.

Filling-In of Broad Far-Red Solar Lines by Terrestrial Fluorescence and Atmospheric Raman Scattering as Detected by SCIAMACHY Satellite Measurements

NASA Technical Reports Server (NTRS)

Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Middleton, E. M.; Campbell, P. K. E.; Yoshida, Y.; Kuze, A.; Corp, L. A.

2011-01-01

Global mapping of terrestrial vegetation fluorescence from space has recently been accomplished with high spectral resolution measurements from the Japanese Greenhouse gases Observing SATellite (GOSAT). These data are of interest because they can potentially provide global information on the functional status of vegetation including light use efficiency and global primary productivity that can be used for global carbon cycle modeling. Quantifying the impact of fluorescence on the O2-A band is important as this band is used for cloud- and aerosol-characterization for other trace-gas retrievals including CO2. Here, we demonstrate that fluorescence information can be derived from space using potentially lower-cost hyperspectral instrumentation, i.e., more than an order of magnitude less spectral resolution than GOSAT, with a relatively simple algorithm. As a demonstration, we use the filling-in of one of the few wide and deep solar Fraunhofer lines in the red and far-red chlorophylla fluorescence bands, the calcium II line near 866 nm, to retrieve fluorescence with the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) satellite instrument. Although the signal from vegetation fluorescence is extremely weak at 866 nm, our results suggest that useful information may be obtained after adjustments are made to the observed spectra to correct for instrumental artifacts. We compare fluorescence from SCIAMACHY with that retrieved at 758 and 770 nm from similarly-corrected GOSAT data as well with the Enhanced Vegetation Index (EVI) from the MODerate-resolution Imaging Spectroradiometer (MODIS). We also show that filling-in occurs at 866 nm over barren areas, possibly originating from luminescent minerals in rock and soil.

Consistent regional fluxes of CH4 and CO2 inferred from GOSAT proxy XCH4 : XCO2 retrievals, 2010-2014

NASA Astrophysics Data System (ADS)

Feng, Liang; Palmer, Paul I.; Bösch, Hartmut; Parker, Robert J.; Webb, Alex J.; Correia, Caio S. C.; Deutscher, Nicholas M.; Domingues, Lucas G.; Feist, Dietrich G.; Gatti, Luciana V.; Gloor, Emanuel; Hase, Frank; Kivi, Rigel; Liu, Yi; Miller, John B.; Morino, Isamu; Sussmann, Ralf; Strong, Kimberly; Uchino, Osamu; Wang, Jing; Zahn, Andreas

2017-04-01

We use the GEOS-Chem global 3-D model of atmospheric chemistry and transport and an ensemble Kalman filter to simultaneously infer regional fluxes of methane (CH4) and carbon dioxide (CO2) directly from GOSAT retrievals of XCH4 : XCO2, using sparse ground-based CH4 and CO2 mole fraction data to anchor the ratio. This work builds on the previously reported theory that takes into account that (1) these ratios are less prone to systematic error than either the full-physics data products or the proxy CH4 data products; and (2) the resulting CH4 and CO2 fluxes are self-consistent. We show that a posteriori fluxes inferred from the GOSAT data generally outperform the fluxes inferred only from in situ data, as expected. GOSAT CH4 and CO2 fluxes are consistent with global growth rates for CO2 and CH4 reported by NOAA and have a range of independent data including new profile measurements (0-7 km) over the Amazon Basin that were collected specifically to help validate GOSAT over this geographical region. We find that large-scale multi-year annual a posteriori CO2 fluxes inferred from GOSAT data are similar to those inferred from the in situ surface data but with smaller uncertainties, particularly over the tropics. GOSAT data are consistent with smaller peak-to-peak seasonal amplitudes of CO2 than either the a priori or in situ inversion, particularly over the tropics and the southern extratropics. Over the northern extratropics, GOSAT data show larger uptake than the a priori but less than the in situ inversion, resulting in small net emissions over the year. We also find evidence that the carbon balance of tropical South America was perturbed following the droughts of 2010 and 2012 with net annual fluxes not returning to an approximate annual balance until 2013. In contrast, GOSAT data significantly changed the a priori spatial distribution of CH4 emission with a 40 % increase over tropical South America and tropical Asia and a smaller decrease over Eurasia and temperate

VLBI Observations of Geostationary Satellites

NASA Astrophysics Data System (ADS)

Artz, T.; Nothnagel, A.; La Porta, L.

2013-08-01

For a consistent realization of a Global Geodetic Observing System (GGOS), a proper tie between the individual global reference systems used in the analysis of space-geodetic observations is a prerequisite. For instance, the link between the terrestrial, the celestial and the dynamic reference system of artificial Earth orbiters may be realized by Very Long O Baseline Interferometry (VLBI) observations of one or several satellites. In the preparation phase for a dedicated satellite mission, one option to realize this is using a geostationary (GEO) satellite emitting a radio signal in X-Band and/or S-Band and, thus, imitating a quasar. In this way, the GEO satellite can be observed by VLBI together with nearby quasars and the GEO orbit can, thus, be determined in a celestial reference frame. If the GEO satellite is, e.g., also equipped with a GNSS-type transmitter, a further tie between GNSS and VLBI may be realized. In this paper, a concept for the generation of a radio signal is shown. Furthermore, simulation studies for estimating the GEO position are presented with a GEO satellite included in the VLBI schedule. VLBI group delay observations are then simulated for the quasars as well as for the GEO satellite. The analysis of the simulated observations shows that constant orbit changes are adequately absorbed by estimated orbit parameters. Furthermore, the post-fit residuals are comparable to those from real VLBI sessions.

The Greenhouse Gas Climate Change Initiative (GHG-CCI): comparative validation of GHG-CCI SCIAMACHY/ENVISAT and TANSO-FTS/GOSAT CO2 and CH4 retrieval algorithm products with measurements from the TCCON

NASA Astrophysics Data System (ADS)

Dils, B.; Buchwitz, M.; Reuter, M.; Schneising, O.; Boesch, H.; Parker, R.; Guerlet, S.; Aben, I.; Blumenstock, T.; Burrows, J. P.; Butz, A.; Deutscher, N. M.; Frankenberg, C.; Hase, F.; Hasekamp, O. P.; Heymann, J.; De Mazière, M.; Notholt, J.; Sussmann, R.; Warneke, T.; Griffith, D.; Sherlock, V.; Wunch, D.

2014-06-01

Column-averaged dry-air mole fractions of carbon dioxide and methane have been retrieved from spectra acquired by the TANSO-FTS (Thermal And Near-infrared Sensor for carbon Observations-Fourier Transform Spectrometer) and SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography) instruments on board GOSAT (Greenhouse gases Observing SATellite) and ENVISAT (ENVIronmental SATellite), respectively, using a range of European retrieval algorithms. These retrievals have been compared with data from ground-based high-resolution Fourier transform spectrometers (FTSs) from the Total Carbon Column Observing Network (TCCON). The participating algorithms are the weighting function modified differential optical absorption spectroscopy (DOAS) algorithm (WFMD, University of Bremen), the Bremen optimal estimation DOAS algorithm (BESD, University of Bremen), the iterative maximum a posteriori DOAS (IMAP, Jet Propulsion Laboratory (JPL) and Netherlands Institute for Space Research algorithm (SRON)), the proxy and full-physics versions of SRON's RemoTeC algorithm (SRPR and SRFP, respectively) and the proxy and full-physics versions of the University of Leicester's adaptation of the OCO (Orbiting Carbon Observatory) algorithm (OCPR and OCFP, respectively). The goal of this algorithm inter-comparison was to identify strengths and weaknesses of the various so-called round- robin data sets generated with the various algorithms so as to determine which of the competing algorithms would proceed to the next round of the European Space Agency's (ESA) Greenhouse Gas Climate Change Initiative (GHG-CCI) project, which is the generation of the so-called Climate Research Data Package (CRDP), which is the first version of the Essential Climate Variable (ECV) "greenhouse gases" (GHGs). For XCO2, all algorithms reach the precision requirements for inverse modelling (< 8 ppm), with only WFMD having a lower precision (4.7 ppm) than the other algorithm products (2.4-2.5 ppm

Stereoscopic observations from meteorological satellites

NASA Astrophysics Data System (ADS)

Hasler, A. F.; Mack, R.; Negri, A.

The capability of making stereoscopic observations of clouds from meteorological satellites is a new basic analysis tool with a broad spectrum of applications. Stereoscopic observations from satellites were first made using the early vidicon tube weather satellites (e.g., Ondrejka and Conover [1]). However, the only high quality meteorological stereoscopy from low orbit has been done from Apollo and Skylab, (e.g., Shenk et al. [2] and Black [3], [4]). Stereoscopy from geosynchronous satellites was proposed by Shenk [5] and Bristor and Pichel [6] in 1974 which allowed Minzner et al. [7] to demonstrate the first quantitative cloud height analysis. In 1978 Bryson [8] and desJardins [9] independently developed digital processing techniques to remap stereo images which made possible precision height measurement and spectacular display of stereograms (Hasler et al. [10], and Hasler [11]). In 1980 the Japanese Geosynchronous Satellite (GMS) and the U.S. GOES-West satellite were synchronized to obtain stereo over the central Pacific as described by Fujita and Dodge [12] and in this paper. Recently the authors have remapped images from a Low Earth Orbiter (LEO) to the coordinate system of a Geosynchronous Earth Orbiter (GEO) and obtained stereoscopic cloud height measurements which promise to have quality comparable to previous all GEO stereo. It has also been determined that the north-south imaging scan rate of some GEOs can be slowed or reversed. Therefore the feasibility of obtaining stereoscopic observations world wide from combinations of operational GEO and LEO satellites has been demonstrated. Stereoscopy from satellites has many advantages over infrared techniques for the observation of cloud structure because it depends only on basic geometric relationships. Digital remapping of GEO and LEO satellite images is imperative for precision stereo height measurement and high quality displays because of the curvature of the earth and the large angular separation of the

Earth Observation Satellites and Chinese Applications

NASA Astrophysics Data System (ADS)

Li, D.

In this talk existing and future Earth observation satellites are briefly described These satellites include meteorological satellites ocean satellites land resources satellites cartographic satellites and gravimetric satellites The Chinese government has paid and will pay more attention to and put more effort into enhancing Chinese earth observation satellite programs in the next fifteen years The utilization of these satellites will effectively help human beings to solve problems it faces in areas such as population natural resources and environment and natural hazards The author will emphasize the originality of the scientific and application aspects of the Chinese program in the field of Earth observations The main applications include early warning and prevention of forest fires flooding and drought disaster water and ocean ice disasters monitoring of landslides and urban subsidence investigation of land cover change and urban expansion as well as urban and rural planning The author introduces the most up-to-date technology used by Chinese scientists including fusion and integration of multi-sensor multi-platform optical and SAR data of remote sensing Most applications in China have obtained much support from related international organizations and universities around the world These applications in China are helpful for economic construction and the efficient improvement of living quality

GOSAT field experiments with a new portable mid-IR FTS in the western US

NASA Astrophysics Data System (ADS)

Shiomi, K.; Kikuchi, N.; Kuze, A.; Suto, H.; Kawakami, S.; Hashimoto, M.; Kataoka, F.; Kasai, K.; Arai, T.; Hedelius, J.; Viatte, C.; Wennberg, P. O.; Roehl, C. M.; Leifer, I.; Yates, E. L.; Marrero, J. E.; Iraci, L. T.; Bruegge, C. J.; Schwandner, F. M.; Crisp, D.

2016-12-01

The column-average dry air mole fractions of carbon dioxide (XCO2), methane (XCH4) and carbon monoxide (XCO) were measured from the surface using direct sunlight at near-IR wavelengths. Simultaneous detection of CO is helpful to characterize CO2 source type. We measured XCO along with XCO2 and XCH4 using a new portable Fourier transform spectrometer (FTS), EM27/SUN mid-IR,in western US field experiments at 1) Caltech, in Pasadena, a northern Los Angeles suburb, 2) Chino, a dairy farming region east of Los Angeles, and 3) Railroad Valley (RRV), a desert playa in Nevada. These measurements were conducted during the GOSAT/OCO-2 joint campaign for vicarious calibration and validation (cal/val) and its preparatory experiments in the early summer of 2016. Before the campaign, measurements from the JAXA EM27/SUN mid-IR were compared with those from the Total Carbon Column Observing Network (TCCON) station at Caltech. Then, we observed a diurnal cycle at the Chino dairy site, an area of concentrated animal husbandry, producing a CH4 point source. Finally, we conducted the cal/val campaign at RRV coincident with GOSAT and OCO-2 overpass observations. Over RRV, in-situ vertical profiles of CO2 and CH4 were measured using the Alpha Jet research aircraft as a part of the NASA Ames Alpha Jet Atmospheric eXperiment (AJAX). We will compare experimental results from the cal/val campaign for XCO2 and XCH4 with the portable FTS.

Development of a generalized algorithm of satellite remote sensing using multi-wavelength and multi-pixel information (MWP method) for aerosol properties by satellite-borne imager

NASA Astrophysics Data System (ADS)

Hashimoto, M.; Nakajima, T.; Morimoto, S.; Takenaka, H.

2014-12-01

We have developed a new satellite remote sensing algorithm to retrieve the aerosol optical characteristics using multi-wavelength and multi-pixel information of satellite imagers (MWP method). In this algorithm, the inversion method is a combination of maximum a posteriori (MAP) method (Rodgers, 2000) and the Phillips-Twomey method (Phillips, 1962; Twomey, 1963) as a smoothing constraint for the state vector. Furthermore, with the progress of computing technique, this method has being combined with the direct radiation transfer calculation numerically solved by each iteration step of the non-linear inverse problem, without using LUT (Look Up Table) with several constraints.Retrieved parameters in our algorithm are aerosol optical properties, such as aerosol optical thickness (AOT) of fine and coarse mode particles, a volume soot fraction in fine mode particles, and ground surface albedo of each observed wavelength. We simultaneously retrieve all the parameters that characterize pixels in each of horizontal sub-domains consisting the target area. Then we successively apply the retrieval method to all the sub-domains in the target area.We conducted numerical tests for the retrieval of aerosol properties and ground surface albedo for GOSAT/CAI imager data to test the algorithm for the land area. The result of the experiment showed that AOTs of fine mode and coarse mode, soot fraction and ground surface albedo are successfully retrieved within expected accuracy. We discuss the accuracy of the algorithm for various land surface types. Then, we applied this algorithm to GOSAT/CAI imager data, and we compared retrieved and surface-observed AOTs at the CAI pixel closest to an AERONET (Aerosol Robotic Network) or SKYNET site in each region. Comparison at several sites in urban area indicated that AOTs retrieved by our method are in agreement with surface-observed AOT within ±0.066.Our future work is to extend the algorithm for analysis of AGEOS-II/GLI and GCOM/C-SGLI data.

Constraining East Asian CO2 emissions with GOSAT retrievals: methods and policy implications

NASA Astrophysics Data System (ADS)

Shim, C.; Henze, D. K.; Deng, F.

2017-12-01

The world largest CO2 emissions are from East Asia. However, there are large uncertainties in CO2 emission inventories, mainly because of imperfections in bottom-up statistics and a lack of observations for validating emission fluxes, particularly over China. Here we tried to constrain East Asian CO2 emissions with GOSAT retrievals applying 4-Dvar GEOS-Chem and its adjoint model. We applied the inversion to only the cold season (November - February) in 2009 - 2010 since the summer monsoon and greater transboundary impacts in spring and fall greatly reduced the GOSAT retrievals. In the cold season, the a posteriori CO2 emissions over East Asia generally higher by 5 - 20%, particularly Northeastern China shows intensively higher in a posteriori emissions ( 20%), where the Chinese government is recently focusing on mitigating the air pollutants. In another hand, a posteriori emissions from Southern China are lower 10 - 25%. A posteriori emissions in Korea and Japan are mostly higher by 10 % except over Kyushu region. With our top-down estimates with 4-Dvar CO2 inversion, we will evaluate the current regional CO2 emissions inventories and potential uncertainties in the sectoral emissions. This study will help understand the quantitative information on anthropogenic CO2 emissions over East Asia and will give policy implications for the mitigation targets.

Spanish Earth Observation Satellite System

NASA Astrophysics Data System (ADS)

Borges, A.; Cerezo, F.; Fernandez, M.; Lomba, J.; Lopez, M.; Moreno, J.; Neira, A.; Quintana, C.; Torres, J.; Trigo, R.; Urena, J.; Vega, E.; Vez, E.

2010-12-01

The Spanish Ministry of Industry, Tourism and Trade (MITyC) and the Ministry of Defense (MoD) signed an agreement in 2007 for the development of a "Spanish Earth Observation Satellite System" based, in first instance, on two satellites: a high resolution optical satellite, called SEOSAT/Ingenio, and a radar satellite based on SAR technology, called SEOSAR/Paz. SEOSAT/Ingenio is managed by MITyC through the Centre for the Development of Industrial Technology (CDTI), with technical and contractual support from the European Space Agency (ESA). HISDESA T together with the Spanish Instituto Nacional de Técnica Aeroespacial (INTA, National Institute for Aerospace Technology) will be responsible for the in-orbit operation and the commercial operation of both satellites, and for the technical management of SEOSAR/Paz on behalf of the MoD. In both cases EADS CASA Espacio (ECE) is the prime contractor leading the industrial consortia. The ground segment development will be assigned to a Spanish consortium. This system is the most important contribution of Spain to the European Programme Global Monitoring for Environment and Security, GMES. This paper presents the Spanish Earth Observation Satellite System focusing on SEOSA T/Ingenio Programme and with special emphasis in the potential contribution to the ESA Third Party Missions Programme and to the Global Monitoring for Environment and Security initiative (GMES) Data Access.

Impact of line parameter database, continuum absorption, full grind configuration, and L1B update on GOSAT TIR methane retrieval

NASA Astrophysics Data System (ADS)

Yamada, A.; Saitoh, N.; Nonogaki, R.; Imasu, R.; Shiomi, K.; Kuze, A.

2016-12-01

The thermal infrared (TIR) band of Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) onboard Greenhouse Gases Observing Satellite (GOSAT) observes CH4 profile at wavenumber range from 1210 cm-1 to 1360 cm-1 including CH4 ν4 band. The current retrieval algorithm (V1.0) uses LBLRTM V12.1 with AER V3.1 line database to calculate optical depth. LBLRTM V12.1 include MT_CKD 2.5.2 model to calculate continuum absorption. The continuum absorption has large uncertainty, especially temperature dependent coefficient, between BPS model and MT_CKD model in the wavenumber region of 1210-1250 cm-1(Paynter and Ramaswamy, 2014). The purpose of this study is to assess the impact on CH4 retrieval from the line parameter databases and the uncertainty of continuum absorption. We used AER v1.0 database, HITRAN2004 database, HITRAN2008 database, AER V3.2 database, and HITRAN2012 database (Rothman et al. 2005, 2009, and 2013. Clough et al., 2005). AER V1.0 database is based on HITRAN2000. The CH4 line parameters of AER V3.1 and V3.2 databases are developed from HITRAN2008 including updates until May 2009 with line mixing parameters. We compared the retrieved CH4 with the HIPPO CH4 observation (Wofsy et al., 2012). The difference of AER V3.2 was the smallest and 24.1 ± 45.9 ppbv. The differences of AER V1.0, HITRAN2004, HITRAN2008, and HITRAN2012 were 35.6 ± 46.5 ppbv, 37.6 ± 46.3 ppbv, 32.1 ± 46.1 ppbv, and 35.2 ± 46.0 ppbv, respectively. Compare AER V3.2 case to HITRAN2008 case, the line coupling effect reduced difference by 8.0 ppbv. Median values of Residual difference from HITRAN2008 to AER V1.0, HITRAN2004, AER V3.2, and HITRAN2012 were 0.6 K, 0.1 K, -0.08 K, and 0.08 K, respectively, while median values of transmittance difference were less than 0.0003 and transmittance differences have small wavenumber dependence. We also discuss the retrieval error from the uncertainty of the continuum absorption, the test of full grid

Latest results from the GreenHouse gas Observations of the Stratosphere and Troposphere (GHOST) airborne shortwave infrared spectrometer

NASA Astrophysics Data System (ADS)

Humpage, Neil; Boesch, Hartmut; Palmer, Paul; Vick, Andy

2017-04-01

GHOST is a novel, compact shortwave infrared grating spectrometer, designed for remote sensing of tropospheric columns of greenhouse gases (GHGs) from an airborne platform. GHOST observes solar radiation at medium to high spectral resolution which has been reflected by the surface, using similar methods to those used by polar orbiting satellites such as the JAXA GOSAT mission, the NASA OCO-2 mission and the forthcoming Copernicus Sentinel 5-Precursor. By using an original design comprising optical fibre inputs along with a single diffraction grating and detector array, GHOST is able to observe CO2 absorption bands centred around 1.61 μm and 2.06 μm (the same wavelength regions used by OCO-2 and GOSAT) whilst simultaneously measuring CH4 absorption at 1.65 μm (also observed by GOSAT), and both CH4 and CO at 2.30 μm (to be observed by Sentinel 5-P once launched later in 2017). The overlapping spectral ranges and comparable spectral resolutions mean that GHOST has unique potential for providing validation opportunities for these platforms, particularly over the ocean where ground-based validation measurements are not available. Here we present the latest results from the spectral analysis, using an optimal estimation based retrieval method, of CO2 and CH4 from GHOST flight spectra for the 1.6 μm band which utilise recently updated laboratory calibration measurements. GHOST took part in two science flights on board the NASA Global Hawk unmanned aerial vehicle based at the Armstrong Flight Research Centre in Edwards, California, in March 2015. These flights involved long approximately north-south transects over the eastern Pacific Ocean. In addition to observing spatial trends in GHG column concentrations over a regional scale, the second of these flights (on 10th March) allows inter-comparisons of GHOST retrievals with observations from OCO-2 and GOSAT, which both passed directly over the Global Hawk during clear sky conditions. We will show results from these

Evaluations of carbon fluxes estimated by top-down and bottom-up approaches

NASA Astrophysics Data System (ADS)

Murakami, K.; Sasai, T.; Kato, S.; Hiraki, K.; Maksyutov, S. S.; Yokota, T.; Nasahara, K.; Matsunaga, T.

2013-12-01

There are two types of estimating carbon fluxes using satellite observation data, and these are referred to as top-down and bottom-up approaches. Many uncertainties are however still remain in these carbon flux estimations, because the true values of carbon flux are still unclear and estimations vary according to the type of the model (e.g. a transport model, a process based model) and input data. The CO2 fluxes in these approaches are estimated by using different satellite data such as the distribution of CO2 concentration in the top-down approach and the land cover information (e.g. leaf area, surface temperature) in the bottom-up approach. The satellite-based CO2 flux estimations with reduced uncertainty can be used efficiently for identifications of large emission area and carbon stocks of forest area. In this study, we evaluated the carbon flux estimates from two approaches by comparing with each other. The Greenhouse gases Observing SATellite (GOSAT) has been observing atmospheric CO2 concentrations since 2009. GOSAT L4A data product is the monthly CO2 flux estimations for 64 sub-continental regions and is estimated by using GOSAT FTS SWIR L2 XCO2 data and atmospheric tracer transport model. We used GOSAT L4A CO2 flux as top-down approach estimations and net ecosystem productions (NEP) estimated by the diagnostic type biosphere model BEAMS as bottom-up approach estimations. BEAMS NEP is only natural land CO2 flux, so we used GOSAT L4A CO2 flux after subtraction of anthropogenic CO2 emissions and oceanic CO2 flux. We compared with two approach in temperate north-east Asia region. This region is covered by grassland and crop land (about 60 %), forest (about 20 %) and bare ground (about 20 %). The temporal variation for one year period was indicated similar trends between two approaches. Furthermore we show the comparison of CO2 flux estimations in other sub-continental regions.

Observing storm surges from satellite altimetry

NASA Astrophysics Data System (ADS)

Han, Guoqi

2016-07-01

Storm surges can cause catastrophic damage to properties and loss of life in coastal communities. Thus it is important to enhance our capabilities of observing and forecasting storm surges for mitigating damage and loss. In this presentation we show examples of observing storm surges around the world using nadir satellite altimetry, during Hurricane Sandy, Igor, and Isaac, as well as other cyclone events. The satellite observations are evaluated against tide-gauge observations and discussed for dynamic mechanisms. We also show the potential of a new wide-swath altimetry mission, the Surface Water and Ocean Topography (SWOT), for observing storm surges.

Optical data communication for Earth observation satellite systems

NASA Astrophysics Data System (ADS)

Fischer, J.; Loecherbach, E.

1991-10-01

The current development status of optical communication engineering in comparison to the conventional microwave systems and the different configurations of the optical data communication for Earth observation satellite systems are described. An outlook to future optical communication satellite systems is given. During the last decade Earth observation became more and more important for the extension of the knowledge about our planet and the human influence on nature. Today pictures taken by satellites are used, for example, to discover mineral resources or to predict harvest, crops, climate, and environment variations and their influence on the population. A new and up to date application for Earth observation satellites can be the verification of disarmament arrangements and the control of crises areas. To solve these tasks a system of Earth observing satellites with sensors tailored to the envisaged mission is necessary. Besides these low Earth orbiting satellites, a global Earth observation system consists of at least two data relay satellites. The communication between the satellites will be established via Inter-Satellite Links (ISL) and Inter-Orbit Links (IOL). On these links, bitrates up to 1 Gbit/s must be taken into account. Due to the increasing scarcity of suitable frequencies, higher carrier frequencies must probably be considered, and possible interference with terrestrial radio relay systems are two main problems for a realization in microwave technique. One important step to tackle these problems is the use of optical frequencies for IOL's and ISL's.

Observation of GEO Satellite Above Thailand’s Sky

NASA Astrophysics Data System (ADS)

Kasonsuwan, K.; Wannawichian, S.; Kirdkao, T.

2017-09-01

The direct observations of Geostationary Orbit (GEO) satellites above Thailand’s sky by 0.7-meters telescope were proceeded at Inthanon Mt., Chiang Mai, Thailand. The observation took place at night with Sidereal Stare Mode (SSM). With this observing mode, the moving object will appear as a streak. The star identification for image calibration is based on (1) a star catalogue, (2) the streak detection of the satellite using the software and (3) the extraction of the celestial coordinate of the satellite as a predicted position. Finally, the orbital elements for GEO satellites were calculated.

AMOS Galaxy 15 Satellite Observations and Analysis

NASA Astrophysics Data System (ADS)

Hall, D.

2011-09-01

In early April 2010, the Galaxy 15 geosynchronous satellite experienced an on-orbit anomaly. Even though the satellite's transmitters and articulating solar panel were still functioning, ground controllers lost the ability to command and maneuver the satellite. With its orbital position no longer maintained, Galaxy 15 began to drift eastward. This forced several other satellites to make collision avoidance maneuvers during the following months. Soon after the initial anomaly, Galaxy 15's operators predicted that the satellite’s reaction wheels would eventually become saturated, causing a loss of both spacecraft attitude and proper sunward orientation of the solar panels. This "off-pointing" event finally occurred in late December, ultimately leading to a depletion of Galaxy 15's batteries. This near-death experience had a fortunate side effect, however, in that it forced the satellite’s command unit to reboot and once again be able to both receive and execute ground commands. The satellite operators have since recovered control of the satellite. AMOS conducted non-resolved photometric observations of Galaxy 15 before, during and after these events. Similar observations were conducted of Galaxy 12, the nearly-identical replacement satellite. This presentation presents and discusses these temporal brightness signatures in detail, comparing the changing patterns in the observations to the known sequence of events.

CCD astrometric observations of Saturnian satellites

NASA Astrophysics Data System (ADS)

Veiga, C. H.; Vieira Martins, R.; Vienne, A.; Thuillot, W.; Arlot, J.-E.

2003-03-01

Astrometric positions of the first eight largest Saturnian satellites and the Lagrangian satellites Helene, Telesto and Calypso are presented from 493 CCD frames taken at the oppositions in 1995 through 1999. The images were obtained over 27 nights. Observed positions are compared with the calculated ones from Vienne and Duriez TASS 1.7 for the large satellites and from JPL positions for the Lagrangian satellites. The rms is about 0farcs 12 for the former but 0farcs 20 for Iapetus and 0farcs 28 for Hyperion. For the Lagrangian satellites it is about 0farcs 21 for Helene, 2farcs 02 for Telesto and 0farcs 60 for Calypso. The catalog (Full Table \\ref{tab4}) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/400/1095 Based on observations made at Laboratório Nacional de Astrofísica/MCT-Itajubá-Brazil.

Commercial observation satellites: broadening the sources of geospatial data

NASA Astrophysics Data System (ADS)

Baker, John C.; O'Connell, Kevin M.; Venzor, Jose A.

2002-09-01

Commercial observation satellites promise to broaden substantially the sources of imagery data available to potential users of geospatial data and related information products. We examine the new trend toward private firms acquiring and operating high-resolution imagery satellites. These commercial observation satellites build on the substantial experience in Earth observation operations provided by government-owned imaging satellites for civilian and military purposes. However, commercial satellites will require governments and companies to reconcile public and private interests in allowing broad public access to high-resolution satellite imagery data without creating national security risks or placing the private firms at a disadvantage compared with other providers of geospatial data.

On the development of earth observation satellite systems

NASA Technical Reports Server (NTRS)

1977-01-01

Subsequent to the launching of the first LANDSAT by NASA, Japan has recognized the importance of data from earth observation satellites, has conducted studies, and is preparing to develop an independent system. The first ocean observation satellite will be launched in 1983, the second in 1985. The first land observation satellite is scheduled to be launched in 1987 and by 1990 Japan intends to have both land and ocean observation systems in regular operation. The association reception and data processing systems are being developed.

Strategies for satellite-based monitoring of CO2 from distributed area and point sources

NASA Astrophysics Data System (ADS)

Schwandner, Florian M.; Miller, Charles E.; Duren, Riley M.; Natraj, Vijay; Eldering, Annmarie; Gunson, Michael R.; Crisp, David

2014-05-01

and sensor provides the full range of temporal sampling needed to characterize distributed area and point source emissions. For instance, point source emission patterns will vary with source strength, wind speed and direction. Because wind speed, direction and other environmental factors change rapidly, short term variabilities should be sampled. For detailed target selection and pointing verification, important lessons have already been learned and strategies devised during JAXA's GOSAT mission (Schwandner et al, 2013). The fact that competing spatial and temporal requirements drive satellite remote sensing sampling strategies dictates a systematic, multi-factor consideration of potential solutions. Factors to consider include vista, revisit frequency, integration times, spatial resolution, and spatial coverage. No single satellite-based remote sensing solution can address this problem for all scales. It is therefore of paramount importance for the international community to develop and maintain a constellation of atmospheric CO2 monitoring satellites that complement each other in their temporal and spatial observation capabilities: Polar sun-synchronous orbits (fixed local solar time, no diurnal information) with agile pointing allow global sampling of known distributed area and point sources like megacities, power plants and volcanoes with daily to weekly temporal revisits and moderate to high spatial resolution. Extensive targeting of distributed area and point sources comes at the expense of reduced mapping or spatial coverage, and the important contextual information that comes with large-scale contiguous spatial sampling. Polar sun-synchronous orbits with push-broom swath-mapping but limited pointing agility may allow mapping of individual source plumes and their spatial variability, but will depend on fortuitous environmental conditions during the observing period. These solutions typically have longer times between revisits, limiting their ability to resolve

An advanced retrieval algorithm for greenhouse gases using polarization information measured by GOSAT TANSO-FTS SWIR I: Simulation study

NASA Astrophysics Data System (ADS)

Kikuchi, N.; Yoshida, Y.; Uchino, O.; Morino, I.; Yokota, T.

2016-11-01

We present an algorithm for retrieving column-averaged dry air mole fraction of carbon dioxide (XCO2) and methane (XCH4) from reflected spectra in the shortwave infrared (SWIR) measured by the TANSO-FTS (Thermal And Near infrared Sensor for carbon Observation Fourier Transform Spectrometer) sensor on board the Greenhouse gases Observing SATellite (GOSAT). The algorithm uses the two linear polarizations observed by TANSO-FTS to improve corrections to the interference effects of atmospheric aerosols, which degrade the accuracy in the retrieved greenhouse gas concentrations. To account for polarization by the land surface reflection in the forward model, we introduced a bidirectional reflection matrix model that has two parameters to be retrieved simultaneously with other state parameters. The accuracy in XCO2 and XCH4 values retrieved with the algorithm was evaluated by using simulated retrievals over both land and ocean, focusing on the capability of the algorithm to correct imperfect prior knowledge of aerosols. To do this, we first generated simulated TANSO-FTS spectra using a global distribution of aerosols computed by the aerosol transport model SPRINTARS. Then the simulated spectra were submitted to the algorithms as measurements both with and without polarization information, adopting a priori profiles of aerosols that differ from the true profiles. We found that the accuracy of XCO2 and XCH4, as well as profiles of aerosols, retrieved with polarization information was considerably improved over values retrieved without polarization information, for simulated observations over land with aerosol optical thickness greater than 0.1 at 1.6 μm.

Global Warming: Evidence from Satellite Observations

NASA Technical Reports Server (NTRS)

Prabhakara, C.; Iacovazzi, R.; Yoo, J.-M.; Dalu, G.; Einaudi, Franco (Technical Monitor)

2000-01-01

Observations made in Channel 2 (53.74 GHz) of the Microwave Sounding Unit (MSU) radiometer, flown onboard sequential, sun-synchronous, polar-orbiting NOAA (National Oceanic and Atmospheric Administration) operational satellites, indicate that the mean temperature of the atmosphere over the globe increased during the period 1980 to 1999. In this study, we have minimized systematic errors in the time series introduced by satellite orbital drift in an objective manner. This is done with the help of the onboard warm-blackbody temperature, which is used in the calibration of the MSU radiometer. The corrected MSU Channel 2 observations of the NOAA satellite series reveal that the vertically-weighted global-mean temperature of the atmosphere, with a peak weight near the mid troposphere, warmed at the rate of 0.13 +/- 0.05 K/decade during 1980 to 1999. The global warming deduced from conventional meteorological data that have been corrected for urbanization effects agrees reasonably with this satellite-deduced result.

Global Warming: Evidence from Satellite Observations

NASA Technical Reports Server (NTRS)

Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.

2001-01-01

Observations made in Channel 2 (53.74 GHz) of the Microwave Sounding Unit (MSU) radiometer, flown on-board sequential, sun-synchronous, polar orbiting NOAA operational satellites, indicate that the mean temperature of the atmosphere over the globe increased during the period 1980 to 1999. In this study we have minimized systematic errors in the time series introduced by the satellite orbital drift in an objective manner. This is done with the help the onboard warm black body temperature, which is used in the calibration of the MSU radiometer. The corrected MSU Channel 2 observations of the NOAA satellite series reveal that the vertically weighted global mean temperature of the atmosphere, with a peak weight near the mid-troposphere, warmed at the rate of 0.13 K per decade (with an uncertainty of 0.05 K per decade) during 1980 to 1999. The global warming deduced from conventional meteorological data that have been corrected for urbanization effects agrees reasonably with this satellite deuced result.

Korea Earth Observation Satellite Program

NASA Astrophysics Data System (ADS)

Baek, Myung-Jin; Kim, Zeen-Chul

via Korea Aerospace Research Institute (KARI) as the prime contractor in the area of Korea earth observation satellite program to enhance Korea's space program development capability. In this paper, Korea's on-going and future earth observation satellite programs are introduced: KOMPSAT- 1 (Korea Multi Purpose Satellite-1), KOMPSAT-2 and Communication, Broadcasting and Meteorological Satellite (CBMS) program. KOMPSAT-1 satellite successfully launched in December 1999 with Taurus launch vehicle. Since launch, KOMPSAT-1 is downlinking images of Korea Peninsular every day. Until now, KOMPSAT-1 has been operated more than 2 and half years without any major hardware malfunction for the mission operation. KOMPSAT-1 payload has 6.6m panchromatic spatial resolution at 685 km on-orbit and the spacecraft bus had NASA TOMS-EP (Total Ozone Mapping Spectrometer-Earth Probe) spacecraft bus heritage designed and built by TRW, U.S.A.KOMPSAT-1 program was international co-development program between KARI and TRW funded by Korean Government. be launched in 2004. Main mission objective is to provide geo-information products based on the multi-spectral high resolution sensor called Multi-Spectral Camera (MSC) which will provide 1m panchromatic and 4m multi-spectral high resolution images. ELOP of Israel is the prime contractor of the MSC payload system and KARI is the total system prime contractor including spacecraft bus development and ground segment. KARI also has the contract with Astrium of Europe for the purpose of technical consultation and hardware procurement. Based on the experience throughout KOMPSAT-1 and KOMPSAT-2 space system development, Korea is expecting to establish the infrastructure of developing satellite system. Currently, KOMPSAT-2 program is in the critical design stage. are scheduled to launch in 2008 and in 2014, respectively. The mission of CBMS consists of two areas. One is of space technology test for the communications mission, and the other is of a real

Terrestrial Observations from NOAA Operational Satellites.

PubMed

Yates, H; Strong, A; McGinnis, D; Tarpley, D

1986-01-31

Important applications to oceanography, hydrology, and agriculture have been developed from operational satellites of the National Oceanic and Atmospheric Administration and are currently expanding rapidly. Areas of interest involving the oceans include sea surface temperature, ocean currents, and ocean color. Satellites can monitor various hydrological phenomena, including regional and global snow cover, river and sea ice extent, and areas of global inundation. Agriculturally important quantities derived from operational satellite observations include precipitation, daily temperature extremes, canopy temperatures, insolation, and snow cover. This overview describes the current status of each area.

Greenhouse gas observations from space: The GHG-CCI project of ESA's Climate Change Initiative

NASA Astrophysics Data System (ADS)

Buchwitz, Michael; Noël, Stefan; Bergamaschi, Peter; Boesch, Hartmut; Bovensmann, Heinrich; Notholt, Justus; Schneising, Oliver; Hasekamp, Otto; Reuter, Maximilian; Parker, Robert; Dils, Bart; Chevallier, Frederic; Zehner, Claus; Burrows, John

2012-07-01

The GHG-CCI project (http://www.esa-ghg-cci.org) is one of several projects of ESA's Climate Change Initiative (CCI), which will deliver various Essential Climate Variables (ECVs). The goal of GHG-CCI is to deliver global satellite-derived data sets of the two most important anthropogenic greenhouse gases (GHGs) carbon dioxide (CO2) and methane (CH4) suitable to obtain information on regional CO2 and CH4 surface sources and sinks as needed for better climate prediction. The GHG-CCI core ECV data products are column-averaged mole fractions of CO2 and CH4, XCO2 and XCH4, retrieved from SCIAMACHY on ENVISAT and TANSO on GOSAT. Other satellite instruments will be used to provide constraints in upper layers such as IASI, MIPAS, and ACE-FTS. Which of the advanced algorithms, which are under development, will be the best for a given data product still needs to be determined. For each of the 4 GHG-CCI core data products - XCO2 and XCH4 from SCIAMACHY and GOSAT - several algorithms are being further developed and the corresponding data products are inter-compared to identify which data product is the most appropriate. This includes comparisons with corresponding data products generated elsewhere, most notably with the operational data products of GOSAT generated at NIES and the NASA/ACOS GOSAT XCO2 product. This activity, the so-called "Round Robin exercise", will be performed in the first two years of this project. At the end of the 2 year Round Robin phase (end of August 2012) a decision will be made which of the algorithms performs best. The selected algorithms will be used to generate the first version of the ECV GHG. In the last six months of this 3 year project the resulting data products will be validated and made available to all interested users. In the presentation and overview about this project will be given focussing on the latest results.

Satellite missions, global environment, and the concept of a global satellite observation information network. The role of the committee on Earth observation satellites (CEOS)

NASA Astrophysics Data System (ADS)

Smith, D. Brent; Williams, David F.; Fujita, Akihiro

The paper traces the development of the Committee on Earth Observation Satellites (CEOS) since its November 1990 Plenary: its restructuring to include major intergovernmental user and international scientific organizational affiliates; its focus on data sharing issues and completion of a CEOS resolution guaranteeing global change researchers access to satellite data at the cost of filling a user request; unfolding of a CEOS-associated initiative of the UK Prime Minister reporting to UNCED delegations on the relevance of satellite missions to the study of the global environment; development of a "Dossier" providing detailed information on all CEOS agency satellite missions, including sensor specifications, ground systems, standard data products, and other information relevant to users; creation of a permanent CEOS Secretariat; and efforts currently underway to assess the feasibility of a global satellite observation information network. Of particular relevance to developing countries, the paper will discuss CEOS efforts to assure broad user access and to foster acceptance of applications in such important areas as disaster monitoring and mitigation, land cover change, weather forecasting, and long-term climate modeling.

Assimilation of Satellite Ozone Observations

NASA Technical Reports Server (NTRS)

Stajner, I.; Winslow, N.; Wargan, K.; Hayashi, H.; Pawson, S.; Rood, R.

2003-01-01

This talk will discuss assimilation of ozone data from satellite-borne instruments. Satellite observations of ozone total columns and profiles have been measured by a series of Total Ozone Mapping Spectrometer (TOMS), Solar Backscatter Ultraviolet (SBUV) instruments, and more recently by the Global Ozone Monitoring Experiment. Additional profile data are provided by instruments on NASA's Upper Atmosphere Research Satellite and by occultation instruments on other platforms. Instruments on Envisat' and future EOS Aura satellite will supply even more comprehensive data about the ozone distribution. Satellite data contain a wealth of information, but they do not provide synoptic global maps of ozone fields. These maps can be obtained through assimilation of satellite data into global chemistry and transport models. In the ozone system at NASA's Data Assimilation Office (DAO) any combination of TOMS, SBUV, and Microwave Limb sounder (MLS) data can be assimilated. We found that the addition of MLS to SBUV and TOMS data in the system helps to constrain the ozone distribution, especially in the polar night region and in the tropics. The assimilated ozone distribution in the troposphere and lower stratosphere is sensitive also to finer changes in the SBUV and TOMS data selection and to changes in error covariance models. All results are established by comparisons of assimilated ozone with independent profiles from ozone sondes and occultation instruments.

Operational Applications of Satellite Snowcover Observations

NASA Technical Reports Server (NTRS)

Rango, A. (Editor); Peterson, R. (Editor)

1980-01-01

The history of remote sensing of snow cover is reviewed and the following topics are covered: various techniques for interpreting LANDSAT and NOAA satellite data; the status of future systems for continuing snow hydrology applications; the use of snow cover observations in streamflow forecasts by Applications Systems Verification and Transfer participants and selected foreign investigators; and the benefits of using satellite snow cover data in runoff prediction.

Overview of the Ocean Observer Satellite Study

NASA Astrophysics Data System (ADS)

Cunningham, J. D.; McGuire, J. P.; Pichel, W. G.; Gerber, A. J.

2002-12-01

A two-year study of ocean satellite remote sensing requirements and instrument/satellite options is nearing completion. This Ocean Observer Study was sponsored by the U.S. Dept. of Commerce/Dept. of Defense/National Aeronautics and Space Administration Integrated Program Office, whose mission is to develop the future U.S. National Polar-Orbiting Operational Environmental Satellite System (NPOESS). A comprehensive Ocean Observer User Requirements Document has been drafted by a team of over 150 government, academic, and private sector scientists, engineers, and administrators. Included are requirements for open and coastal ocean surface, cryospheric, hydrologic, and some land/hazard and atmospheric boundary layer parameters. This document was then used as input to the instrument and satellite study (conducted by the Jet Propulsion Laboratory) which produced five different instrument/satellite configuration options designed to address the maximum number of requirements which will not be met with the already-approved NPOESS instruments. Instruments studied include a synthetic aperture radar (SAR), an altimeter, and a hyper-spectral coastal infrared/visible imager. After analyzing the alternatives, it appears that one of the best options is a two-satellite system consisting of (1) an altimeter mission in the Topex/Poseidon orbit carrying both wide-swath and delayed doppler altimeters, and (2) a multi-polarization, multi-frequency, multi-mode interferometric SAR mission including a coastal imager in a polar sun-synchronous orbit. This paper summarizes the user requirements process, briefly describes the notional satellite configuration, and presents some of the capabilities of the instruments.

Satellite observed thermodynamics during FGGE

NASA Technical Reports Server (NTRS)

Smith, W. L.

1985-01-01

During the First Global Atmospheric Research Program (GARP) Global Experiment (FGGE), determinations of temperature and moisture were made from TIROS-N and NOAA-6 satellite infrared and microwave sounding radiance measurements. The data were processed by two methods differing principally in their horizontal resolution. At the National Earth Satellite Service (NESS) in Washington, D.C., the data were produced operationally with a horizontal resolution of 250 km for inclusion in the FGGE Level IIb data sets for application to large-scale numerical analysis and prediction models. High horizontal resolution (75 km) sounding data sets were produced using man-machine interactive methods for the special observing periods of FGGE at the NASA/Goddard Space Flight Center and archived as supplementary Level IIb. The procedures used for sounding retrieval and the characteristics and quality of these thermodynamic observations are given.

Lessons Learned from GOSAT; Instrument Design, Calibration, Operation, Data Processing, and International Collaboration

NASA Astrophysics Data System (ADS)

Kuze, A.; Suto, H.; Shiomi, K.; Nakajima, M.

2012-12-01

Advantage of satellite observation is its ability to monitor long term and global distribution with a single instrument. Ozone observation from space has been successful for long term monitoring purposes. Monitoring gradual increase and distribution of greenhouse gases in the troposphere with sub-percent accuracy has become a challenging subject. Interference of cloud and aerosol in radiative transfer has to be corrected for troposphere measurement. Accurate O2-A band measurement can retrieve surface pressure and aerosol distribution property. We have selected a Fourier Transform spectrometer (FTS) to achieve high throughput and wide spectral coverage with uniform spectral resolution. On the other hand, it is difficult to modulate short wave such as 0.76μm and avoid micro vibration interference. Prelaunch, we took special care to select optical components of excellent surface quality and isolate vibration. Design parameters such as IFOV, spectral resolution, observation interval within limited satellite resources must be carefully optimized. Greenhouse gases Observing SATellite (GOSAT) has been providing global high spectral resolution data for almost 4 years. Instrument performance, radiometric calibration, radiative transfer calculation and laboratory spectroscopy are all important. The first step was to reduce bias of column-averaged dry air mole fractions (the Level 2 product) of CO2 and CH4 (XCO2 and XCH4) and validate using well calibrated data such as TCCON. After 2 years of operation, latitudinal distribution of zonal mean and seasonal variation at these sites can be measured with better than 2ppm accuracy. However, validations are limited to ideal conditions. Next step is to evaluate consistency of measured values from long periods since launch, different surface types, and various input radiance with different instrument gain. For long term radiometric calibration, we have uses vicarious, onboard solar diffuser, and lunar calibration data. Over the ocean

Energetic Particle Observations from Fengyun-2G Satellite

NASA Astrophysics Data System (ADS)

Wang, C.

2017-12-01

Observations of high energy electrons and protons with High Energy Particle Instrument(HEPI) carried on the Fengyun-2G( FY-2G )satellite are presented. The instrument consists of two sets detectors- high energy electrons detector which can measure 200keV to greater than 4MeV electrons with eleven channels, and high energy protons and heavy ions detector which mainly senses incident flux of solar protons with seven channels from 4MeV to 300 MeV. The observation results showed both of the detectors can reach an accurate response to various disturbances and can provide refined particles data. Comparison of particles dynamic observations of FY2G satellite with GOES series satellites appears that energetic particle fluxes can enter into a coherent level on some quasi-quiet conditions, great difference occur on disturbances times, which can be helpful for data assimilation of multi-satellite as well as further research in more complicated magnetosphere energy particle dynamics.

Towards TCCON Tropics: Assessment and Measurements of Carbon and its Climate Impacts in Southeast Asia (T3AM C2lImA)

NASA Astrophysics Data System (ADS)

Morino, I.; Velazco, V. A.; Schwandner, F. M.; Macatangay, R. C.; Griffith, D. W. T.

2015-12-01

TCCON (Total Carbon Column Observing Network) measurements of CO2 and CH4 have been and are currently used extensively and globally for satellite validation, for comparison with atmospheric chemistry models and to study atmosphere-biosphere exchanges of carbon. With the global effort to cap greenhouse gas emissions, TCCON has become vital for validating satellite-based greenhouse gas data from past, current and future missions like Japanese GOSAT (Greenhouse Gas Observing SATellite) and GOSAT-2, NASA's OCO-2 (Orbiting Carbon Observatory-2) and OCO-3, ESA's Carbon Monitoring Satellite (CarbonSat), Chinese TanSat, and others. The lack of reliable validation data for the satellite-based greenhouse gas observing missions in the tropical regions is a common limitation in global carbon-cycle modeling studies that have a tropical component. The international CO2 modeling community have specified a requirement for "expansion of the CO2 observation network within the tropics" to reduce uncertainties in regional estimates of CO2 sources and sinks using atmospheric transport models. A TCCON site in the western tropical Pacific is a logical next step in obtaining additional knowledge that would greatly contribute to the understanding of the Earth's atmosphere and better constraining a major tropical region experiencing tremendous economic and population growth. Here, we present a complete site assessment for a possible TCCON site in the Philippines and our decision on the site where a new TCCON FTS will be installed. This site assessment was conducted in cooperation with the Energy Development Corporation (EDC, Philippines), National Institute for Environmental Studies (NIES, Japan), University of Wollongong (UoW, Australia), NASA's Jet Propulsion Laboratory (JPL), the University of the Philippines (UP-IESM), the TCCON science team, and the GOSAT-2 science team.

Quantifying global fossil-fuel CO2 emissions: from OCO-2 to optimal observing designs

NASA Astrophysics Data System (ADS)

Ye, X.; Lauvaux, T.; Kort, E. A.; Oda, T.; Feng, S.; Lin, J. C.; Yang, E. G.; Wu, D.; Kuze, A.; Suto, H.; Eldering, A.

2017-12-01

Cities house more than half of the world's population and are responsible for more than 70% of the world anthropogenic CO2 emissions. Therefore, quantifications of emissions from major cities, which are only less than a hundred intense emitting spots across the globe, should allow us to monitor changes in global fossil-fuel CO2 emissions, in an independent, objective way. Satellite platforms provide favorable temporal and spatial coverage to collect urban CO2 data to quantify the anthropogenic contributions to the global carbon budget. We present here the optimal observation design for future NASA's OCO-2 and Japanese GOSAT missions, based on real-data (i.e. OCO-2) experiments and Observing System Simulation Experiments (OSSE's) to address different error components in the urban CO2 budget calculation. We identify the major sources of emission uncertainties for various types of cities with different ecosystems and geographical features, such as urban plumes over flat terrains, accumulated enhancements within basins, and complex weather regimes in coastal areas. Atmospheric transport errors were characterized under various meteorological conditions using the Weather Research and Forecasting (WRF) model at 1-km spatial resolution, coupled to the Open-source Data Inventory for Anthropogenic CO2 (ODIAC) emissions. We propose and discuss the optimized urban sampling strategies to address some difficulties from the seasonality in cloud cover and emissions, vegetation density in and around cities, and address the daytime sampling bias using prescribed diurnal cycles. These factors are combined in pseudo data experiments in which we evaluate the relative impact of uncertainties on inverse estimates of CO2 emissions for cities across latitudinal and climatological zones. We propose here several sampling strategies to minimize the uncertainties in target mode for tracking urban fossil-fuel CO2 emissions over the globe for future satellite missions, such as OCO-3 and future

Improving UK Air Quality Modelling Through Exploitation of Satellite Observations

NASA Astrophysics Data System (ADS)

Pope, Richard; Chipperfield, Martyn; Savage, Nick

2014-05-01

In this work the applicability of satellite observations to evaluate the operational UK Met Office Air Quality in the Unified Model (AQUM) have been investigated. The main focus involved the AQUM validation against satellite observations, investigation of satellite retrieval error types and of synoptic meteorological-atmospheric chemistry relationships simulated/seen by the AQUM/satellite. The AQUM is a short range forecast model of atmospheric chemistry and aerosols up to 5 days. It has been designed to predict potentially hazardous air pollution events, e.g. high concentrations of surface ozone. The AQUM has only been validated against UK atmospheric chemistry recording surface stations. Therefore, satellite observations of atmospheric chemistry have been used to further validate the model, taking advantage of better satellite spatial coverage. Observations of summer and winter 2006 tropospheric column NO2 from both OMI and SCIAMACHY show that the AQUM generally compares well with the observations. However, in northern England positive biases (AQUM - satellite) suggest that the AQUM overestimates column NO2; we present results of sensitivity experiments on UK emissions datasets suspected to be the cause. In winter, the AQUM over predicts background column NO2 when compared to both satellite instruments. We hypothesise that the cause is the AQUM winter night-time chemistry, where the NO2 sinks are not substantially defined. Satellite data are prone to errors/uncertainty such as random, systematic and smoothing errors. We have investigated these error types and developed an algorithm to calculate and reduce the random error component of DOAS NO2 retrievals, giving more robust seasonal satellite composites. The Lamb Weather Types (LWT), an objective method of classifying the daily synoptic weather over the UK, were used to create composite satellite maps of column NO2 under different synoptic conditions. Under cyclonic conditions, satellite observed UK column NO2 is

Solar energy microclimate as determined from satellite observations

NASA Technical Reports Server (NTRS)

Vonder Haar, T. H.; Ellis, J. S.

1975-01-01

A method is presented for determining solar insolation at the earth's surface using satellite broadband visible radiance and cloud imagery data, along with conventional in situ measurements. Conventional measurements are used to both tune satellite measurements and to develop empirical relationships between satellite observations and surface solar insolation. Cloudiness is the primary modulator of sunshine. The satellite measurements as applied in this method consider cloudiness both explicitly and implicitly in determining surface solar insolation at space scales smaller than the conventional pyranometer network.

Transcontinental Surface Validation of Satellite Observations of Enhanced Methane Anomalies Associated with Fossil Fuel Industrial Methane Emissions

NASA Astrophysics Data System (ADS)

Leifer, I.; Culling, D.; Schneising, O.; Bovensmann, H.; Buchwitz, M.; Burrows, J. P.

2012-12-01

A ground-based, transcontinental (Florida to California - i.e., satellite-scale) survey was conducted to understand better the role of fossil fuel industrial (FFI) fugitive emissions of the potent greenhouse gas, methane. Data were collected by flame ion detection gas chromatography (Fall 2010) and by a cavity ring-down sensor (Winter 2012) from a nearly continuously moving recreational vehicle, allowing 24/7 data collection. Nocturnal methane measurements for similar sources tended to be higher compared to daytime values, sometime significantly, due to day/night meteorological differences. Data revealed strong and persistent FFI methane sources associated with refining, a presumed major pipeline leak, and several minor pipeline leaks, a coal loading plant, and areas of active petroleum production. Data showed FFI source emissions were highly transient and heterogeneous; however, integrated over these large-scale facilities, methane signatures overwhelmed that of other sources, creating clearly identifiable plumes that were well elevated above ambient. The highest methane concentration recorded was 39 ppm at an active central valley California production field, while desert values were as low as 1.80 ppm. Surface methane data show similar trends with strong emissions correlated with FFI on large (4° bin) scales and positive methane anomalies centered on the Gulf Coast area of Houston, home to most of US refining capacity. Comparison with SCIAMACHY and GOSAT satellite data show agreement with surface data in the large-scale methane spatial patterns. Positive satellite methane anomalies in the southeast and Mexico largely correlated with methane anthropogenic and wetland inventory models suggests most strong ground methane anomalies in the Gulf of Mexico region were related to dominant FFI input for most seasons. Wind advection played a role, in some cases confounding a clear relationship. Results are consistent with a non-negligible underestimation of the FFI

Infrared observations of outer planet satellites

NASA Technical Reports Server (NTRS)

Johnson, T. V.

1988-01-01

This task supports IR observations of the outer planet satellites. These data provide vital information about the thermophysical properties of satellite surfaces, including internal heat sources for Io. Observations include both broad and narrow band measurementsin the 2 to 20 micrometer spectral range. The program in the last year has aimed at obtaining lonitude coverage on Io to establish stability of hot spot patterns previously reported. Several runs produced the most complete data set for an apparition since the start of the program. Unfortunately, bad weather limited coverage of key longitude ranges containing the largest known hot spot Loki. Among the preliminary results is the observation of an outburst in Io's thermal flux that was measured at 4.8, 8.7 and 20 micrometer. Analysis of the data has given the best evidence to date of silicate volcanism on Io; this is one of the most significant pieces of the puzzle as to the relative roles of silicate and sulfur volcanism on Io. Researchers are collaborating with J. Goguen (NRC RRA to finish reduction of mutual event data, which have already improved ephermeris information for the satellites. The data appear to place significant limits on the characteristics of any leading side hot spots.

The Earth Phenomena Observing System: Intelligent Autonomy for Satellite Operations

NASA Technical Reports Server (NTRS)

Ricard, Michael; Abramson, Mark; Carter, David; Kolitz, Stephan

2003-01-01

Earth monitoring systems of the future may include large numbers of inexpensive small satellites, tasked in a coordinated fashion to observe both long term and transient targets. For best performance, a tool which helps operators optimally assign targets to satellites will be required. We present the design of algorithms developed for real-time optimized autonomous planning of large numbers of small single-sensor Earth observation satellites. The algorithms will reduce requirements on the human operators of such a system of satellites, ensure good utilization of system resources, and provide the capability to dynamically respond to temporal terrestrial phenomena. Our initial real-time system model consists of approximately 100 satellites and large number of points of interest on Earth (e.g., hurricanes, volcanoes, and forest fires) with the objective to maximize the total science value of observations over time. Several options for calculating the science value of observations include the following: 1) total observation time, 2) number of observations, and the 3) quality (a function of e.g., sensor type, range, slant angle) of the observations. An integrated approach using integer programming, optimization and astrodynamics is used to calculate optimized observation and sensor tasking plans.

Globally Gridded Satellite observations for climate studies

USGS Publications Warehouse

Knapp, K.R.; Ansari, S.; Bain, C.L.; Bourassa, M.A.; Dickinson, M.J.; Funk, Chris; Helms, C.N.; Hennon, C.C.; Holmes, C.D.; Huffman, G.J.; Kossin, J.P.; Lee, H.-T.; Loew, A.; Magnusdottir, G.

2011-01-01

Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them that no central archive of geostationary data for all international satellites exists, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multisatellite climate studies. The International Satellite Cloud Climatology Project (ISCCP) set the stage for overcoming these issues by archiving a subset of the full-resolution geostationary data at ~10-km resolution at 3-hourly intervals since 1983. Recent efforts at NOAA's National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in Network Common Data Format (netCDF) using standards that permit a wide variety of tools and libraries to process the data quickly and easily. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

Satellite Type Estination from Ground-based Photometric Observation

NASA Astrophysics Data System (ADS)

Endo, T.; Ono, H.; Suzuki, J.; Ando, T.; Takanezawa, T.

2016-09-01

The optical photometric observation is potentially a powerful tool for understanding of the Geostationary Earth Orbit (GEO) objects. At first, we measured in laboratory the surface reflectance of common satellite materials, for example, Multi-layer Insulation (MLI), mono-crystalline silicon cells, and Carbon Fiber Reinforced Plastic (CFRP). Next, we calculated visual magnitude of a satellite by simplified shape and albedo. In this calculation model, solar panels have dimensions of 2 by 8 meters, and the bus area is 2 meters squared with measured optical properties described above. Under these conditions, it clarified the brightness can change the range between 3 and 4 magnitudes in one night, but color index changes only from 1 to 2 magnitudes. Finally, we observed the color photometric data of several GEO satellites visible from Japan multiple times in August and September 2014. We obtained that light curves of GEO satellites recorded in the B and V bands (using Johnson filters) by a ground-base optical telescope. As a result, color index changed approximately from 0.5 to 1 magnitude in one night, and the order of magnitude was not changed in all cases. In this paper, we briefly discuss about satellite type estimation using the relation between brightness and color index obtained from the photometric observation.

Small Aperture Telescope Observations of Co-located Geostationary Satellites

NASA Astrophysics Data System (ADS)

Scott, R.; Wallace, B.

As geostationary orbit (GEO) continues to be populated, satellite operators are increasing usage of co-location techniques to maximize usage of fewer GEO longitude slots. Co-location is an orbital formation strategy where two or more geostationary satellites reside within one GEO stationkeeping box. The separation strategy used to prevent collision between the co-located satellites generally uses eccentricity (radial separation) and inclination (latitude separation) vector offsets. This causes the satellites to move in relative motion ellipses about each other as the relative longitude drift between the satellites is near zero. Typical separations between the satellites varies from 1 to 100 kilometers. When co-located satellites are observed by optical ground based space surveillance sensors the participants appear to be separated by a few minutes of arc or less in angular extent. Under certain viewing geometries, these satellites appear to visually conjunct even though the satellites are, in fact, well separated spatially. In situations where one of the co-located satellites is more optically reflective than the other, the reflected sunglint from the more reflective satellite can overwhelm the other. This less frequently encountered issue causes the less reflective satellite to be glint masked in the glare of the other. This paper focuses on space surveillance observations on co-located Canadian satellites using a small optical telescope operated by Defence R&D Canada - Ottawa. The two above mentioned problems (cross tagging and glint masking) are investigated and we quantify the results for Canadian operated geostationary satellites. The performance of two line element sets when making in-frame CCD image correlation between the co-located satellites is also examined. Relative visual magnitudes between the co-located members are also inspected and quantified to determine the susceptibility of automated telescopes to glint masking of co-located satellite members.

Satellite observations of ground water changes in New Mexico

USDA-ARS?s Scientific Manuscript database

In 2002 NASA launched the Gravity Recovery and Climate Experiment (GRACE) satellite mission. GRACE consists of two satellites with a separation of about 200 km.  By accurately measuring the separation between the twin satellites, the differences in the gravity field can be determined. Monthly observ...

CEOS Committee on Earth Observations Satellites Consolidated Report, 1992

NASA Technical Reports Server (NTRS)

1992-01-01

A concise overview of the committee on Earth Observations Satellites (CEOS) and its Working Groups, covering the history and purpose of the Committee and its accomplishments to date are provided. The report will be updated annually before each Plenary meeting, and as developments in the Working Groups warrant. The committee on Earth Observations Satellites (originally named the International Earth Observations Satellite committee, IEOS) was treated in 1984, in response to a recommendation from the Economic Summit of Industrialized Nations Working Group on Growth, Technology, and Employment's Panel of Experts on Satellite Remote Sensing. This group recognized the multidisciplinary nature of satellite Earth observations, and the value of coordinating across all proposed missions. Thus, CEOS combined the previously existing groups for coordination on Ocean Remote-Sensing Satellites (CORSS) and coordination on Land Remote-Sensing Satellites (CLRSS), and established a broad framework for coordination across all spaceborne Earth observations missions. The first three LEOS Plenary meetings focused on treating and guiding the Working Groups deemed necessary to carry out the objectives of the CEOS members. After the third meeting, it was agreed that a more active orientation was required by the Plenary, and additional issues were brought before the group at the fourth meeting. At the fifth Plenary, international scientific programs and relevant intergovernmental organizations accepted invitations and participated as affiliate members of CEOS. This enabled progress toward integrating satellite data users' requirements into the CEOS process. Data exchange principles for global change research were also adopted. An interim CEOS Plenary meeting was held in April 1992, in preparation for the United Nations Conference on Environment and Development (UNCED). Brief encapsulations of the Plenary sessions immediately follow the Terms of Reference that govern the activities of CEOS as

Use of meteorological satellite observations in weather modification programs

NASA Technical Reports Server (NTRS)

Dennis, A. S.; Smith, P. L., Jr.; Biswas, K. R.

1973-01-01

The potential value of weather satellite data in field operations of weather modification is appraised. It was found that satellites could play a useful role in operational weather modification projects, particularly in the recognition of treatment opportunities. Satellite cloud photographs and infrared observations appear promising in the identification of treatment opportunities in seeding orographic cloud systems for increased snowpack, in seeding convective clouds for increased rainfall, in identifying hail threats, and in tracking and observing hurricanes as an aid to timing and location of seeding treatments. It was concluded that the potential value of satellite data in the treatment and evaluation phases of operational projects is not as great as in the recognition of treatment opportunity.

Interferometric observations of an artificial satellite.

PubMed

Preston, R A; Ergas, R; Hinteregger, H F; Knight, C A; Robertson, D S; Shapiro, I I; Whitney, A R; Rogers, A E; Clark, T A

1972-10-27

Very-long-baseline interferometric observations of radio signals from the TACSAT synchronous satellite, even though extending over only 7 hours, have enabled an excellent orbit to be deduced. Precision in differenced delay and delay-rate measurements reached 0.15 nanosecond ( approximately 5 centimeters in equivalent differenced distance) and 0.05 picosecond per second ( approximately 0.002 centimeter per second in equivalent differenced velocity), respectively. The results from this initial three-station experiment demonstrate the feasibility of using the method for accurate satellite tracking and for geodesy. Comparisons are made with other techniques.

Planning and Scheduling for Fleets of Earth Observing Satellites

NASA Technical Reports Server (NTRS)

Frank, Jeremy; Jonsson, Ari; Morris, Robert; Smith, David E.; Norvig, Peter (Technical Monitor)

2001-01-01

We address the problem of scheduling observations for a collection of earth observing satellites. This scheduling task is a difficult optimization problem, potentially involving many satellites, hundreds of requests, constraints on when and how to service each request, and resources such as instruments, recording devices, transmitters, and ground stations. High-fidelity models are required to ensure the validity of schedules; at the same time, the size and complexity of the problem makes it unlikely that systematic optimization search methods will be able to solve them in a reasonable time. This paper presents a constraint-based approach to solving the Earth Observing Satellites (EOS) scheduling problem, and proposes a stochastic heuristic search method for solving it.

Precision of natural satellite ephemerides from observations of different types

NASA Astrophysics Data System (ADS)

Emelyanov, N. V.

2017-08-01

Currently, various types of observations of natural planetary satellites are used to refine their ephemerides. A new type of measurement - determining the instants of apparent satellite encounters - has recently been proposed by Morgado and co-workers. The problem that arises is which type of measurement to choose in order to obtain an ephemeris precision that is as high as possible. The answer can be obtained only by modelling the entire process: observations, obtaining the measured values, refining the satellite motion parameters, and generating the ephemeris. The explicit dependence of the ephemeris precision on observational accuracy as well as on the type of observations is unknown. In this paper, such a dependence is investigated using the Monte Carlo statistical method. The relationship between the ephemeris precision for different types of observations is then assessed. The possibility of using the instants of apparent satellite encounters to obtain an ephemeris is investigated. A method is proposed that can be used to fit the satellite orbital parameters to this type of measurement. It is shown that, in the absence of systematic scale errors in the CCD frame, the use of the instants of apparent encounters leads to less precise ephemerides. However, in the presence of significant scale errors, which is often the case, this type of measurement becomes effective because the instants of apparent satellite encounters do not depend on scale errors.

Investigation of Greenhouse Gas Emissions by Surface, Airborne, and Satellite on Local to Continental-Scale

NASA Astrophysics Data System (ADS)

Leifer, I.; Tratt, D. M.; Egland, E. T.; Gerilowski, K.; Vigil, S. A.; Buchwitz, M.; Krings, T.; Bovensmann, H.; Krautwurst, S.; Burrows, J. P.

2013-12-01

In situ meteorological observations, including 10-m winds (U), in conjunction with greenhouse gas (GHG - methane, carbon dioxide, water vapor) measurements by continuous wave Cavity Enhanced Absorption Spectroscopy (CEAS) were conducted onboard two specialized platforms: MACLab (Mobile Atmospheric Composition Laboratory in a RV) and AMOG Surveyor (AutoMObile Greenhouse gas) - a converted commuter automobile. AMOG Surveyor data were collected for numerous southern California sources including megacity, geology, fossil fuel industrial, animal husbandry, and landfill operations. MACLab investigated similar sources along with wetlands on a transcontinental scale from California to Florida to Nebraska covering more than 15,000 km. Custom software allowing real-time, multi-parameter data visualization (GHGs, water vapor, temperature, U, etc.) improved plume characterization and was applied to large urban area and regional-scale sources. The capabilities demonstrated permit calculation of source emission strength, as well as enable documenting microclimate variability. GHG transect data were compared with airborne HyperSpectral Imaging data to understand temporal and spatial variability and to ground-truth emission strength derived from airborne imagery. These data also were used to validate satellite GHG products from SCIAMACHY (2003-2005) and GOSAT (2009-2013) that are currently being analyzed to identify significant decadal-scale changes in North American GHG emission patterns resulting from changes in anthropogenic and natural sources. These studies lay the foundation for the joint ESA/NASA COMEX campaign that will map GHG plumes by remote sensing and in situ measurements for a range of strong sources to derive emission strength through inverse plume modeling. COMEX is in support of the future GHG monitoring satellites, such as CarbonSat and HyspIRI. GHG transect data were compared with airborne HyperSpectral Imaging data to understand temporal and spatial variability

The Chinese FY-1 Meteorological Satellite Application in Observation on Oceanic Environment

NASA Astrophysics Data System (ADS)

Weimin, S.

meteorological satellite is stated in this paper. exploration of the ocean resources has been a very important question of global strategy in the world. The exploration of the ocean resources includes following items: Making full use of oceanic resources and space, protecting oceanic environment. to observe the ocean is by using of satellite. In 1978, US successfully launched the first ocean observation satellite in the world --- Sea Satellite. It develops ancient oceanography in to advanced space-oceanography. FY-1 B and FY- IC respectively. High quality data were acquired at home and abroad. FY-1 is Chinese meteorological satellite, but with 0.43 ~ 0.48 μm ,0.48 ~ 0.53 μm and 0.53 ~ 0.58 μm three ocean color channels, actually it is a multipurpose remote sensing satellite of meteorology and oceanography. FY-1 satellite's capability of observation on ocean partly, thus the application field is expanded and the value is increased. With the addition of oceanic channels on FY-1, the design of the satellite is changed from the original with meteorological observation as its main purpose into remote sensing satellite possessing capability of observing meteorology and ocean as well. Thus, the social and economic benefit of FY-1 is increased. the social and economic benefit of the development of the satellite is the key technique in the system design of the satellite. technically feasible but also save the funds in researching and manufacturing of the satellite, quicken the tempo of researching and manufacturing satellite. the scanning radiometer for FY-1 is conducted an aviation experiment over Chinese ocean. This experiment was of vital importance to the addition of oceanic observation channel on FY-1. FY-1 oceanic channels design to be correct. detecting ocean color. This is the unique character of Chinese FY-1 meteorological satellite. meteorological remote sensing channel on FY-1 to form detecting capability of three visible channels: red, yellow and blue

An analysis of satellite state vector observability using SST tracking data

NASA Technical Reports Server (NTRS)

Englar, T. S., Jr.; Hammond, C. L.

1976-01-01

Observability of satellite state vectors, using only SST tracking data was investigated by covariance analysis under a variety of satellite and station configurations. These results indicate very precarious observability in most short arc cases. The consequences of this are large variances on many state components, such as the downrange component of the relay satellite position. To illustrate the impact of observability problems, an example is given of two distinct satellite orbit pairs generating essentially the same data arc. The physical bases for unobservability are outlined and related to proposed TDRSS configurations. Results are relevant to any mission depending upon TDRSS to determine satellite state. The required mathematical analysis and the software used is described.

Applications of Satellite Observations of Tropospheric Composition

NASA Astrophysics Data System (ADS)

Monks, Paul S.; Beirle, Steffen

A striking feature of the field of tropospheric composition is the sheer number of chemical species that have been detected and measured with satellite instruments. The measurements have found application both in atmospheric chemistry itself, providing evidence, for example, of unexpected cryochemistry in the Arctic regions, and also in environmental monitoring with, for example, the observed growth in NO2 emissions over eastern Asia. Chapter 8 gives an overview of the utility of satellite observations for measuring tropospheric composition, dealing with each of the many compounds seen in detail. A comprehensive compound by compound table of the many studies performed is a most useful feature.

Students as Ground Observers for Satellite Cloud Retrieval Validation

NASA Technical Reports Server (NTRS)

Chambers, Lin H.; Costulis, P. Kay; Young, David F.; Rogerson, Tina M.

2004-01-01

The Students' Cloud Observations On-Line (S'COOL) Project was initiated in 1997 to obtain student observations of clouds coinciding with the overpass of the Clouds and the Earth's Radiant Energy System (CERES) instruments on NASA's Earth Observing System satellites. Over the past seven years we have accumulated more than 9,000 cases worldwide where student observations are available within 15 minutes of a CERES observation. This paper reports on comparisons between the student and satellite data as one facet of the validation of the CERES cloud retrievals. Available comparisons include cloud cover, cloud height, cloud layering, and cloud visual opacity. The large volume of comparisons allows some assessment of the impact of surface cover, such as snow and ice, reported by the students. The S'COOL observation database, accessible via the Internet at http://scool.larc.nasa.gov, contains over 32,000 student observations and is growing by over 700 observations each month. Some of these observations may be useful for assessment of other satellite cloud products. In particular, some observing sites have been making hourly observations of clouds during the school day to learn about the diurnal cycle of cloudiness.

Model of load distribution for earth observation satellite

NASA Astrophysics Data System (ADS)

Tu, Shumin; Du, Min; Li, Wei

2017-03-01

For the system of multiple types of EOS (Earth Observing Satellites), it is a vital issue to assure that each type of payloads carried by the group of EOS can be used efficiently and reasonably for in astronautics fields. Currently, most of researches on configuration of satellite and payloads focus on the scheduling for launched satellites. However, the assignments of payloads for un-launched satellites are bit researched, which are the same crucial as the scheduling of tasks. Moreover, the current models of satellite resources scheduling lack of more general characteristics. Referring the idea about roles-based access control (RBAC) of information system, this paper brings forward a model based on role-mining of RBAC to improve the generality and foresight of the method of assignments of satellite-payload. By this way, the assignment of satellite-payload can be mapped onto the problem of role-mining. A novel method will be introduced, based on the idea of biclique-combination in graph theory and evolutionary algorithm in intelligence computing, to address the role-mining problem of satellite-payload assignments. The simulation experiments are performed to verify the novel method. Finally, the work of this paper is concluded.

Observing outer planet satellites (except Titan) with JWST: Science justification and observational requirements

USGS Publications Warehouse

Kestay, Laszlo P.; Grundy, Will; Stansberry, John; Sivaramakrishnan, Anand; Thatte, Deepashri; Gudipati, Murthy; Tsang, Constantine; Greenbaum, Alexandra; McGruder, Chima

2016-01-01

The James Webb Space Telescope (JWST) will allow observations with a unique combination of spectral, spatial, and temporal resolution for the study of outer planet satellites within our Solar System. We highlight the infrared spectroscopy of icy moons and temporal changes on geologically active satellites as two particularly valuable avenues of scientific inquiry. While some care must be taken to avoid saturation issues, JWST has observation modes that should provide excellent infrared data for such studies.

Satellite Observations for Detecting and Tracking Changes in Atmospheric Composition

NASA Technical Reports Server (NTRS)

Neil, Doreen O.; Kondragunbta, Shobha; Osterman, Gregory; Pickering, Kenneth; Pinder, Robert W.; Prados, Ana I.; Szykman, James

2009-01-01

The satellite observations provide constraints on detailed atmospheric modeling, including emissions inventories, indications of transport, harmonized data over vast areas suitable for trends analysis, and a link between spatial scales ranging from local to global, and temporal scales from diurnal to interannual. 1 The National Oceanic and Atmospheric Administration's (NOAA) long-term commitments help provide these observations in cooperation with international meteorological organizations. NASA s long-term commitments will advance scientifically important observations as part of its Earth Science Program, and will assist the transition of the science measurements to applied analyses through the Applied Science Program. Both NASA and NOAA have begun to provide near realtime data and tools to visualize and analyze satellite data,2 while maintaining data quality, validation, and standards. Consequently, decision-makers can expect satellite data services to support air quality decision making now and in the future. The international scientific community's Integrated Global Atmosphere Chemistry Observation System Report3 outlined a plan for ground-based, airborne and satellite measurements and models to integrate the observations into a four-dimensional representation of the atmosphere (space and time) to support assessment and policy information needs. This plan is being carried out under the Global Earth Observation System of Systems (GEOSS). Demonstrations of such an integrated capability4 provide new understanding of the changing atmosphere and link policy decisions to benefits for society. In this article, we highlight the use of satellite data to constrain biomass burning emissions, to assess oxides of nitrogen (NO(x)) emission reductions, and to contribute to state implementation plans, as examples of the use of satellite observations for detecting and tracking changes in atmospheric composition.

Observing tectonic plate motions and deformations from satellite laser ranging

NASA Technical Reports Server (NTRS)

Christodoulidis, D. C.; Smith, D. E.; Kolenkiewicz, R.; Klosko, S. M.; Torrence, M. H.

1985-01-01

The scope of geodesy has been greatly affected by the advent of artificial near-earth satellites. The present paper provides a description of the results obtained from the reduction of data collected with the aid of satellite laser ranging. It is pointed out that dynamic reduction of satellite laser ranging (SLR) data provides very precise positions in three dimensions for the laser tracking network. The vertical components of the stations, through the tracking geometry provided by the global network and the accurate knowledge of orbital dynamics, are uniquely related to the center of mass of the earth. Attention is given to the observations, the methodologies for reducing satellite observations to estimate station positions, Lageos-observed tectonic plate motions, an improved temporal resolution of SLR plate motions, and the SLR vertical datum.

Quantifying the Observability of CO2 Flux Uncertainty in Atmospheric CO2 Records Using Products from Nasa's Carbon Monitoring Flux Pilot Project

NASA Technical Reports Server (NTRS)

Ott, Lesley; Pawson, Steven; Collatz, Jim; Watson, Gregg; Menemenlis, Dimitris; Brix, Holger; Rousseaux, Cecile; Bowman, Kevin; Bowman, Kevin; Liu, Junjie;

NOAA satellite observing systems: status and plans

NASA Astrophysics Data System (ADS)

John Hussey, W.; Schneider, Stanley R.; Gird, Ronald S.; Needham, Bruce H.

1991-07-01

NOAA's National Environmental Satellite, Data, and Information Service (NESDIS) operates separates series of environmental monitoring satellites in polar and geostationary orbits. Two geostationary spacecraft are normally in opration: one stationed at 75° E longitude (GOES-EAST), and one stationed at 135° W longitude (GOES-WEST). Owing to a combination of premature in-orbit failures and a launch failure there is only one GOES satellite currently operational, GOES-7, which is migrated between 95° and 105° W longitude depending upon season. GOES-7 was launched in February 1987. Its primary observing instrument is a combined imager/sounder, the VISSR Atmospheric Sounder (VAS). The first in the next series of GOES satellite, (GOES I-M), is scheduled for launch in 1992. The major upgrade over the current GOES satellites will be the introduction of simultaneous imaging and sounding capability and improvements in imaging IR and sounding resolution. Because of the long lead times necessary in designing and building new systems, NOAA, in cooperation with NASA, has already begun the planning and study process for the GOES-N series of satellites, which will fly early in the next century. NOAA operates a two polar satellite system with equatorial nodal crossing times of 0730 (descending) and 1345 (ascending). The current operational satellites are NOAA-10 (AM) and NOAA-11 (PM). The next in the series (NOAA-D, which will become NOAA-12 once operational) is scheduled for launch in early summer 1991. The instruments onboard are used to make global measurements of numerous parameters such as atmospheric temperature, water vapor, ozone, sea surface temperature, sea ice, and vegetation. The NOAA K-N series of satellites, scheduled for deployment in the mid 1990's, will provide upgraded imaging and sounding capability. The imager will be enhanced to include a sixth channel for cloud/ice descrimination. A 15 channel advanced microwave sounder will be manifested for atmospheric

Satellite observation of particulate organic carbon dynamics in ...

EPA Pesticide Factsheets

Particulate organic carbon (POC) plays an important role in coastal carbon cycling and the formation of hypoxia. Yet, coastal POC dynamics are often poorly understood due to a lack of long-term POC observations and the complexity of coastal hydrodynamic and biogeochemical processes that influence POC sources and sinks. Using field observations and satellite ocean color products, we developed a nw multiple regression algorithm to estimate POC on the Louisiana Continental Shelf (LCS) from satellite observations. The algorithm had reliable performance with mean relative error (MRE) of ?40% and root mean square error (RMSE) of ?50% for MODIS and SeaWiFS images for POC ranging between ?80 and ?1200 mg m23, and showed similar performance for a large estuary (Mobile Bay). Substantial spatiotemporal variability in the satellite-derived POC was observed on the LCS, with high POC found on the inner shelf (<10 m depth) and lower POC on the middle (10–50 m depth) and outer shelf (50–200 m depth), and with high POC found in winter (January–March) and lower POC in summer to fall (August–October). Correlation analysis between long-term POC time series and several potential influencing factors indicated that river discharge played a dominant role in POC dynamics on the LCS, while wind and surface currents also affected POC spatial patterns on short time scales. This study adds another example where satellite data with carefully developed algorithms can greatly increase

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.

Observing Climate with Satellites - Are We on Thin Ice?

NASA Technical Reports Server (NTRS)

Tucker, Compton

2012-01-01

The Earth s climate is determined by irradiance from the Sun and properties of the atmosphere, oceans, and land that determine the reflection, absorption, and emission of energy within our atmosphere and at the Earth s surface. Since the 1970s, Earth-viewing satellites have complimented non-satellite geophysical observations with consistent, quantitative, and spatially-continuous measurements that have led to an unprecedented understanding of the Earth s climate system. I will describe the Earth s climate system as elaborated by satellite and in situ observations, review arguments against global warming, and show the convergence of evidence for human-caused warming of our planet.

QSAT: The Satellite for Polar Plasma Observation

NASA Astrophysics Data System (ADS)

Tsuruda, Yoshihiro; Fujimoto, Akiko; Kurahara, Naomi; Hanada, Toshiya; Yumoto, Kiyohumi; Cho, Mengu

2009-04-01

This paper introduces QSAT, the satellite for polar plasma observation. The QSAT project began in 2006 as an initiative by graduate students of Kyushu University, and has the potential to contribute greatly to IHY (International Heliophysical Year) by showing to the world the beauty, importance, and relevance of space science. The primary objectives of the QSAT mission are (1) to investigate plasma physics in the Earth’s aurora zone in order to better understand spacecraft charging, and (2) to conduct a comparison of the field-aligned current observed in orbit with ground-based observations. The QSAT project can provide education and research opportunities for students in an activity combining space sciences and satellite engineering. The QSAT satellite is designed to be launched in a piggyback fashion with the Japanese launch vehicle H-IIA. The spacecraft bus is being developed at the Department of Aeronautics and Astronautics of Kyushu University with collaboration of Fukuoka Institute of Technology. Regarding the payload instruments, the Space Environment Research Center of Kyushu University is developing the magnetometers, whereas the Laboratory of Spacecraft Environment Interaction Engineering of Kyushu Institute of Technology is developing the plasma probes. We aim to be ready for launch in 2009 or later.

The joint methane profiles retrieval approach from GOSAT TIR and SWIR spectra

NASA Astrophysics Data System (ADS)

Zadvornykh, Ilya V.; Gribanov, Konstantin G.; Zakharov, Vyacheslav I.; Imasu, Ryoichi

2017-11-01

In this paper we present a method, using methane as example, which allows more accurate greenhouse gases retrieval in the Earth's atmosphere. Using the new version of the FIRE-ARMS software, supplemented with the VLIDORT vector radiation transfer model, we carried out joint methane retrieval from TIR (Thermal Infrared Range) and SWIR (ShortWavelength Infrared Range) GOSAT spectra using optimal estimation method. MACC reanalysis data from the European Center for Medium-Range Forecasts (ECMWF), supplemented by data from aircraft measurements of the HIPPO experiment were used as a statistical ensemble.

Desert Test Site Uniformity Analysis

NASA Technical Reports Server (NTRS)

Kerola, Dana X.; Bruegge, Carol J.

2009-01-01

Desert test sites such as Railroad Valley (RRV) Nevada, Egypt-1, and Libya-4 are commonly targeted to assess the on-orbit radiometric performance of sensors. Railroad Valley is used for vicarious calibration experiments, where a field-team makes ground measurements to produce accurate estimates of top-of-atmosphere (TOA) radiances. The Sahara desert test sites are not instrumented, but provide a stable target that can be used for sensor cross-comparisons, or for stability monitoring of a single sensor. These sites are of interest to NASA's Atmospheric Carbon Observation from Space (ACOS) and JAXA's Greenhouse Gas Observation SATellite (GOSAT) programs. This study assesses the utility of these three test sites to the ACOS and GOSAT calibration teams. To simulate errors in sensor-measured radiance with pointing errors, simulated data have been created using MODIS Aqua data. MODIS data are further utilized to validate the campaign data acquired from June 22 through July 5, 2009. The first GOSAT vicarious calibration experiment was conducted during this timeframe.

The NOAA Satellite Observing System Architecture Study

NASA Technical Reports Server (NTRS)

Volz, Stephen; Maier, Mark; Di Pietro, David

2016-01-01

NOAA is beginning a study, the NOAA Satellite Observing System Architecture (NSOSA) study, to plan for the future operational environmental satellite system that will follow GOES and JPSS, beginning about 2030. This is an opportunity to design a modern architecture with no pre-conceived notions regarding instruments, platforms, orbits, etc. The NSOSA study will develop and evaluate architecture alternatives to include partner and commercial alternatives that are likely to become available. The objectives will include both functional needs and strategic characteristics (e.g., flexibility, responsiveness, sustainability). Part of this study is the Space Platform Requirements Working Group (SPRWG), which is being commissioned by NESDIS. The SPRWG is charged to assess new or existing user needs and to provide relative priorities for observational needs in the context of the future architecture. SPRWG results will serve as input to the process for new foundational (Level 0 and Level 1) requirements for the next generation of NOAA satellites that follow the GOES-R, JPSS, DSCOVR, Jason-3, and COSMIC-2 missions.

Observations of the Natural Planetary Satellites for Dynamical and Physical Purpose

NASA Astrophysics Data System (ADS)

Arlot, J. E.; Thuillot, W.; Fienga, A.; Bec-Borsenberger, A.; Baron, N.; Berthier, J.; Colas, F.; Descamps, P.

1999-12-01

At the Institut de mecanique celeste-Bureau des longitudes, we started several programs of observation of the natural planetary satellites. First, we took the opportunity of the transit of the Earth and the Sun in the equatorial plane of Jupiter to observe the mutual phenomena of the Galilean satellites. These observations provide astrometric data of high accuracy useful for dynamical studies of the motions of the satellites and photometric data allowing to characterize the surfaces of the satellites. A campaign was organized leading to 400 light curves made throughout the world in about 40 countries. Second, we started astrometric CCD observations of the faint satellites of Jupiter JVI to JXIII and of the satellite of Saturn Phoebe (SIX) for dynamical purpose at Observatoire de Haute Provence using the 120cm-telescope. PPM, Hipparcos and USNO A.2 catalogue were used for calibration in order to get absolute J2000 R.A. and declination of these objects. In August and December, 1998, CCD observations provided 43 absolute positions of JVI, 23 of JVII, 53 of JVIII, 35 of JIX, 29 of JX, 27 of JXI, 18 of JXII, 16 of JXIII and 135 of SIX (Phoebe). A campaign will also take place in 1999.

Global canopy interception from satellite observations

USDA-ARS?s Scientific Manuscript database

A new methodology for retrieving rainfall interception rates from multi satellite observations is presented. The approach makes use of the daily productof the Global Precipitation Climatology Project (GPCP) as driving data and applies Gash’s analytical model to derive interception rates at global sc...

Global Monitoring of Terrestrial Chlorophyll Fluorescence from Moderate-spectral-resolution Near-infrared Satellite Measurements: Methodology, Simulations, and Application to GOME-2

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

Global Monitoring of Terrestrial Chlorophyll Fluorescence from Moderate-Spectral-Resolution Near-Infrared Satellite Measurements: Methodology, Simulations, and Application to GOME-2

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

Globally Gridded Satellite (GridSat) Observations for Climate Studies

NASA Technical Reports Server (NTRS)

Knapp, Kenneth R.; Ansari, Steve; Bain, Caroline L.; Bourassa, Mark A.; Dickinson, Michael J.; Funk, Chris; Helms, Chip N.; Hennon, Christopher C.; Holmes, Christopher D.; Huffman, George J.;

Satellite Observation Systems for Polar Climate Change Studies

NASA Technical Reports Server (NTRS)

Comiso, Josefino C.

2012-01-01

The key observational tools for detecting large scale changes of various parameters in the polar regions have been satellite sensors. The sensors include passive and active satellite systems in the visible, infrared and microwave frequencies. The monitoring started with Tiros and Nimbus research satellites series in the 1970s but during the period, not much data was stored digitally because of limitations and cost of the needed storage systems. Continuous global data came about starting with the launch of ocean color, passive microwave, and thermal infrared sensors on board Nimbus-7 and Synthetic Aperture Radar, Radar Altimeter and Scatterometer on board SeaSat satellite both launched in 1978. The Nimbus-7 lasted longer than expected and provided about 9 years of useful data while SeaSat quit working after 3 months but provided very useful data that became the baseline for follow-up systems with similar capabilities. Over the years, many new sensors were launched, some from Japan Aeronautics and Space Agency (JAXA), some from the European Space Agency (ESA) and more recently, from RuSSia, China, Korea, Canada and India. For polar studies, among the most useful sensors has been the passive microwave sensor which provides day/night and almost all weather observation of the surface. The sensor provide sea surface temperature, precipitation, wind, water vapor and sea ice concentration data that have been very useful in monitoring the climate of the region. More than 30 years of such data are now available, starting with the Scanning Multichannel Microwave Radiometer (SMMR) on board the Nimbus-7, the Special Scanning Microwave/Imager (SSM/I) on board a Defense Meteorological Satellite Program (DMSP) and the Advanced Microwave Scanning Radiometer on board the EOS/ Aqua satellite. The techniques that have been developed to derive geophysical parameters from data provided by these and other sensors and associated instrumental and algorithm errors and validation techniques

Initial Assessment of Cyclone Global Navigation Satellite System (CYGNSS) Observations

NASA Astrophysics Data System (ADS)

McKague, D. S.; Ruf, C. S.

2017-12-01

The NASA Cyclone Global Navigation Satellite System (CYNSS) mission provides high temporal resolution observations of cyclones from a constellation of eight low-Earth orbiting satellites. Using the relatively new technique of Global Navigation Satellite System reflectometry (GNSS-R), all-weather observations are possible, penetrating even deep convection within hurricane eye walls. The compact nature of the GNSS-R receivers permits the use of small satellites, which in turn enables the launch of a constellation of satellites from a single launch vehicle. Launched in December of 2016, the eight CYGNSS satellites provide 25 km resolution observations of mean square slope (surface roughness) and surface winds with a 2.8 hour median revisit time from 38 S to 38 N degrees latitude. In addition to the calibration and validation of CYGNSS sea state observations, the CYGNSS science team is assessing the ability of the mission to provide estimates of cyclone size, intensity, and integrated kinetic energy. With its all-weather ability and high temporal resolution, the CYGNSS mission will add significantly to our ability to monitor cyclone genesis and intensification and will significantly reduce uncertainties in our ability to estimate cyclone intensity, a key variable in predicting its destructive potential. Members of the CYGNSS Science Team are also assessing the assimilation of CYGNSS data into hurricane forecast models to determine the impact of the data on forecast skill, using the data to study extra-tropical cyclones, and looking at connections between tropical cyclones and global scale weather, including the global hydrologic cycle. This presentation will focus on the assessment of early on-orbit observations of cyclones with respect to these various applications.

Improving BeiDou precise orbit determination using observations of onboard MEO satellite receivers

NASA Astrophysics Data System (ADS)

Ge, Haibo; Li, Bofeng; Ge, Maorong; Shen, Yunzhong; Schuh, Harald

2017-12-01

In recent years, the precise orbit determination (POD) of the regional Chinese BeiDou Navigation Satellite System (BDS) has been a hot spot because of its special constellation consisting of five geostationary earth orbit (GEO) satellites and five inclined geosynchronous satellite orbit (IGSO) satellites besides four medium earth orbit (MEO) satellites since the end of 2012. GEO and IGSO satellites play an important role in regional BDS applications. However, this brings a great challenge to the POD, especially for the GEO satellites due to their geostationary orbiting. Though a number of studies have been carried out to improve the POD performance of GEO satellites, the result is still much worse than that of IGSO and MEO, particularly in the along-track direction. The major reason is that the geostationary characteristic of a GEO satellite results in a bad geometry with respect to the ground tracking network. In order to improve the tracking geometry of the GEO satellites, a possible strategy is to mount global navigation satellite system (GNSS) receivers on MEO satellites to collect the signals from GEO/IGSO GNSS satellites so as that these observations can be used to improve GEO/IGSO POD. We extended our POD software package to simulate all the related observations and to assimilate the MEO-onboard GNSS observations in orbit determination. Based on GPS and BDS constellations, simulated studies are undertaken for various tracking scenarios. The impact of the onboard GNSS observations is investigated carefully and presented in detail. The results show that MEO-onboard observations can significantly improve the orbit precision of GEO satellites from metres to decimetres, especially in the along-track direction. The POD results of IGSO satellites also benefit from the MEO-onboard data and the precision can be improved by more than 50% in 3D direction.

On the Cloud Observations in JAXA's Next Coming Satellite Missions

NASA Technical Reports Server (NTRS)

Nakajima, Takashi Y.; Nagao, Takashi M.; Letu, Husi; Ishida, Haruma; Suzuki, Kentaroh

2012-01-01

The use of JAXA's next generation satellites, the EarthCARE and the GCOM-C, for observing overall cloud systems on the Earth is discussed. The satellites will be launched in the middle of 2010-era and contribute for observing aerosols and clouds in terms of climate change, environment, weather forecasting, and cloud revolution process study. This paper describes the role of such satellites and how to use the observing data showing concepts and some sample viewgraphs. Synergistic use of sensors is a key of the study. Visible to infrared bands are used for cloudy and clear discriminating from passively obtained satellite images. Cloud properties such as the cloud optical thickness, the effective particle radii, and the cloud top temperature will be retrieved from visible to infrared wavelengths of imagers. Additionally, we are going to combine cloud properties obtained from passive imagers and radar reflectivities obtained from an active radar in order to improve our understanding of cloud evolution process. This is one of the new techniques of satellite data analysis in terms of cloud sciences in the next decade. Since the climate change and cloud process study have mutual beneficial relationship, a multispectral wide-swath imagers like the GCOM-C SGLI and a comprehensive observation package of cloud and aerosol like the EarthCARE are both necessary.

Evaluating Surface Radiation Fluxes Observed From Satellites in the Southeastern Pacific Ocean

NASA Astrophysics Data System (ADS)

Pinker, R. T.; Zhang, B.; Weller, R. A.; Chen, W.

2018-03-01

This study is focused on evaluation of current satellite and reanalysis estimates of surface radiative fluxes in a climatically important region. It uses unique observations from the STRATUS Ocean Reference Station buoy in a region of persistent marine stratus clouds 1,500 km off northern Chile during 2000-2012. The study shows that current satellite estimates are in better agreement with buoy observations than model outputs at a daily time scale and that satellite data depict well the observed annual cycle in both shortwave and longwave surface radiative fluxes. Also, buoy and satellite estimates do not show any significant trend over the period of overlap or any interannual variability. This verifies the stability and reliability of the satellite data and should make them useful to examine El Niño-Southern Oscillation variability influences on surface radiative fluxes at the STRATUS site for longer periods for which satellite record is available.

Observations of Uranus' satellites: Bibliography and literature search

NASA Technical Reports Server (NTRS)

Jacobson, R. A.

1985-01-01

A literature search has yielded more than 10,000 observations of the satellites of Uranus made from 1787 to 1985. The type (photographic, micrometer) and the number of observations are tabulated in 5 year increments and a complete bibliography is provided.

History of telescopic observations of the Martian satellites

NASA Astrophysics Data System (ADS)

Pascu, D.; Erard, S.; Thuillot, W.; Lainey, V.

2014-11-01

This article intends to review the different studies of the Mars satellites Phobos and Deimos realized by means of ground-based telescopic observations as well in the astrometry and dynamics domain as in the physical one. This study spans the first period of investigations of the Martian satellites since their discovery in 1877 through the astrometry and the spectrometry methods, mainly before the modern period of the space era. It includes also some other observations performed thanks to the Hubble Space Telescope. The different techniques used and the main results obtained for the positionning, the size estimate, the albedo and surface composition are described.

Scheduling Earth Observing Satellites with Evolutionary Algorithms

NASA Technical Reports Server (NTRS)

Globus, Al; Crawford, James; Lohn, Jason; Pryor, Anna

2003-01-01

We hypothesize that evolutionary algorithms can effectively schedule coordinated fleets of Earth observing satellites. The constraints are complex and the bottlenecks are not well understood, a condition where evolutionary algorithms are often effective. This is, in part, because evolutionary algorithms require only that one can represent solutions, modify solutions, and evaluate solution fitness. To test the hypothesis we have developed a representative set of problems, produced optimization software (in Java) to solve them, and run experiments comparing techniques. This paper presents initial results of a comparison of several evolutionary and other optimization techniques; namely the genetic algorithm, simulated annealing, squeaky wheel optimization, and stochastic hill climbing. We also compare separate satellite vs. integrated scheduling of a two satellite constellation. While the results are not definitive, tests to date suggest that simulated annealing is the best search technique and integrated scheduling is superior.

History of Satellite Observations of East Pacific Atmospheric Rivers

NASA Astrophysics Data System (ADS)

Vonder Haar, T. H.; Forsythe, J. M.; Seaman, C.

2017-12-01

The terms "Atmospheric River" or "Tropospheric River" were not used in refereed literature until the 1990's, although earlier works hinted at the existence of narrow corridors of moisture transport. With the advent of satellite observations in the 1960's, meteorologists began to discover the fingerprints of these phenomena via cloud observations. Early geostationary satellites depicted "cloud rivers" or "pipeline cirrus" impacting the U.S. west coast, with only indirect evidence of large water vapor transport. Routine use of passive microwave imagery to retrieve total column water vapor began in the late 1980's with the launch of the Special Sensor Microwave / Imager instrument, whose descendants continue to provide realtime monitoring of atmospheric rivers today. Passive microwave data opened the door to quantitative studies of atmospheric rivers, by providing the water vapor measurements needed to compute integrated moisture flux. Atmospheric rivers are detected in near-realtime from passive microwave water vapor products. In recent years, dedicated coastal observatories, multidecadal global water vapor data sets, cloud radars, and satellite sounding systems have begun to probe the 4-dimensional moisture structure of atmospheric rivers. The timeline of our understanding of atmospheric rivers will be presented from the standpoint of evolving satellite observing systems.

Numerically Integrated Orbits of the Major Saturnian Satellites fit to Earthbased Observations

NASA Technical Reports Server (NTRS)

Jacobson, R. A.; Vaughan, R. M.

1993-01-01

We have fit numerically integrated orbits of the eight major satellites of Saturn to all available astrometric and meridian circle observations for the period of 1971 to 1992. The integration was carried out in cartesian coordinates in the J2000 system. The force model included the gravitational effects of the oblate primary, the mutual perturbations of the satellites, and perturbations due to Jupiter and the Sun. Values of the gravitational parameters of the Saturnian system, e.g. planet and satellite masses, were taken from Campbell, et. al., 1989, only the epoch state vectors of the satellites were adjusted to obtain orbits which fit the observations. All astrometric data was processed in the form of satellite relative positions which were weighted according to observer and opposition to reflect the varying data quality...

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009334 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009458 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

Multi-layer Retrievals of Greenhouse Gases from a Combined Use of GOSAT TANSO-FTS SWIR and TIR

NASA Astrophysics Data System (ADS)

Kikuchi, N.; Kuze, A.; Kataoka, F.; Shiomi, K.; Hashimoto, M.; Suto, H.; Knuteson, R. O.; Iraci, L. T.; Yates, E. L.; Gore, W.; Tanaka, T.; Yokota, T.

2016-12-01

The TANSO-FTS sensor onboard GOSAT has three frequency bands in the shortwave infrared (SWIR) and the fourth band in the thermal infrared (TIR). Observations of high-resolution spectra of reflected sunlight in the SWIR are extensively utilized to retrieve column-averaged concentrations of the major greenhouse gases such as carbon dioxide (XCO2) and methane (XCH4). Although global XCO2 and XCH4 distribution retrieved from SWIR data can reduce the uncertainty in the current knowledge about sources and sinks of these gases, information on the vertical profiles would be more useful to constrain the surface flux and also to identify the local emission sources. Based on the degrees of freedom for signal, Kulawik et al. (2016, IWGGMS-12 presentation) shows that 2-layer information on the concentration of CO2 can be extracted from TANSO-FTS SWIR measurements, and the retrieval error is predicted to be about 5 ppm in the lower troposphere. In this study, we present multi-layer retrievals of CO2 and CH4 from a combined use of measurements of TANSO-FTS SWIR and TIR. We selected GOSAT observations at Railroad Valley Playa in Nevada, USA, which is a vicarious calibration site for TANSO-FTS, as we have various ancillary data including atmospheric temperature and humidity taken by a radiosonde, surface temperature, and surface emissivity with a ground based FTS. All of these data are useful especially for retrievals using TIR spectra. Currently, we use the 700-800 cm-1 and 1200-1300 cm-1 TIR windows for CO2 and CH4 retrievals, respectively, in addition to the SWIR bands. We found that by adding TIR windows, 3-layer information can be extracted, and the predicted retrieval error in the CO2 concentration was reduced about 1 ppm in the lower troposphere. We expect that the retrieval error could be further reduced by optimizing TIR windows and by reducing systematic forward model errors.

Accuracy of Satellite Optical Observations and Precise Orbit Determination

NASA Astrophysics Data System (ADS)

Shakun, L.; Koshkin, N.; Korobeynikova, E.; Strakhova, S.; Dragomiretsky, V.; Ryabov, A.; Melikyants, S.; Golubovskaya, T.; Terpan, S.

The monitoring of low-orbit space objects (LEO-objects) is performed in the Astronomical Observatory of Odessa I.I. Mechnikov National University (Ukraine) for many years. Decades-long archives of these observations are accessible within Ukrainian network of optical observers (UMOS). In this work, we give an example of orbit determination for the satellite with the 1500-km height of orbit based on angular observations in our observatory (Int. No. 086). For estimation of the measurement accuracy and accuracy of determination and propagation of satellite position, we analyze the observations of Ajisai satellite with the well-determined orbit. This allows making justified conclusions not only about random errors of separate measurements, but also to analyze the presence of systematic errors, including external ones to the measurement process. We have shown that the accuracy of one measurement has the standard deviation about 1 arcsec across the track and 1.4 arcsec along the track and systematical shifts in measurements of one track do not exceed 0.45 arcsec. Ajisai position in the interval of the orbit fitting is predicted with accuracy better than 30 m along the orbit and better than 10 m across the orbit for any its point.

Simultaneous ground-satellite observations of daytime traveling ionospheric disturbances over Japan using the GPS-TEC network and the CHAMP satellite

NASA Astrophysics Data System (ADS)

Moral, A. C.; Shiokawa, K.; Otsuka, Y.; Liu, H.; Nishioka, M.; Tsugawa, T.

2017-12-01

We report results of simultaneous ground-satellite measurements of daytime travelling ionospheric disturbances (TIDs) over Japan by using the GEONET GPS receiver network and the CHAMP satellite. For the two years of 2002 and 2008, we examined GPS measurements of TEC (Total Electron Content) and neutral and electron densities measured by CHAMP satellite. Total of fifteen TID events with clear southward moving structures in the GPS-TEC measurements are found by simultaneous ground-satellite measurements. On 2002, simultaneous events are only observed in January (1 event) and February (4 events). On 2008, ten events are observed around winter months (January (3 events), February (5), March (1), and October (1)). Neutral and electron densities measured by CHAMP show quasi-periodic fluctuations throughout the passages for all events. The CHAMP satellite crossed at least one clear TID phase front for all the events. We fitted a sinusoidal function to both ground and satellite data to obtain the frequencies and phase of the observed variations. We calculated the corresponding phase relationships between TEC variations and neutral and electron densities measured by CHAMP to categorize the events. In the presentations we report correspondence of these TID structures seen in the simultaneous ground-satellite observations by GPS-TEC and CHAMP, and discuss their phase relationship to identify the source of the daytime TIDs and specify how much of the observed variations are showing clear frequencies/or not in the nature at middle latitudes.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009315 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A blue and white part of Earth provides the backdrop for the scene.

Assimilating Satellite SST Observations into a Diurnal Cycle Model

NASA Astrophysics Data System (ADS)

Pimentel, S.; Haines, K.; Nichols, N. K.

2006-12-01

The wealth of satellite sea surface temperature (SST) data now available opens the possibility of large improvements in SST estimation. However the use of such data is not straight forward; a major difficulty in assimilating satellite observations is that they represent a near surface temperature, whereas in ocean models the top level represents the temperature at a greater depth. During the day, under favourable conditions of clear skies and calm winds, the near surface temperature is often seen to have a diurnal cycle that is picked up in satellite observations. Current ocean models do not have the vertical or temporal resolution to adequately represent this daytime warming. The usual approach is to discard daytime observations as they are considered diurnally `corrupted'. A new assimilation technique is developed here that assimilates observations into a diurnal cycle model. The diurnal cycle of SSTs are modelled using a 1-D mixed layer model with fine near surface resolution and 6 hourly forcing from NWP analyses. The accuracy of the SST estimates are hampered by uncertainties in the forcing data. The extent of diurnal SST warming at a particular location and time is predominately governed by a non-linear response to cloud cover and sea surface wind speeds which greatly affect the air-sea fluxes. The method proposed here combines infrared and microwave SST satellite observations in order to derive corrections to the cloud cover and wind speed values over the day. By adjusting the forcing, SST estimation and air-sea fluxes should be improved and are at least more consistent with each other. This new technique for assimilating SST data can be considered a tool for producing more accurate diurnal warming estimates.

Bias assessment of lower and middle tropospheric CO2 concentrations of GOSAT/TANSO-FTS TIR version 1 product

NASA Astrophysics Data System (ADS)

Saitoh, Naoko; Kimoto, Shuhei; Sugimura, Ryo; Imasu, Ryoichi; Shiomi, Kei; Kuze, Akihiko; Niwa, Yosuke; Machida, Toshinobu; Sawa, Yousuke; Matsueda, Hidekazu

2017-10-01

CO2 observations in the free troposphere can be useful for constraining CO2 source and sink estimates at the surface since they represent CO2 concentrations away from point source emissions. The thermal infrared (TIR) band of the Thermal and Near Infrared Sensor for Carbon Observation (TANSO) Fourier transform spectrometer (FTS) on board the Greenhouse Gases Observing Satellite (GOSAT) has been observing global CO2 concentrations in the free troposphere for about 8 years and thus could provide a dataset with which to evaluate the vertical transport of CO2 from the surface to the upper atmosphere. This study evaluated biases in the TIR version 1 (V1) CO2 product in the lower troposphere (LT) and the middle troposphere (MT) (736-287 hPa), on the basis of comparisons with CO2 profiles obtained over airports using Continuous CO2 Measuring Equipment (CME) in the Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL) project. Bias-correction values are presented for TIR CO2 data for each pressure layer in the LT and MT regions during each season and in each latitude band: 40-20° S, 20° S-20° N, 20-40° N, and 40-60° N. TIR V1 CO2 data had consistent negative biases of 1-1.5 % compared with CME CO2 data in the LT and MT regions, with the largest negative biases at 541-398 hPa, partly due to the use of 10 µm CO2 absorption band in conjunction with 15 and 9 µm absorption bands in the V1 retrieval algorithm. Global comparisons between TIR CO2 data to which the bias-correction values were applied and CO2 data simulated by a transport model based on the Nonhydrostatic ICosahedral Atmospheric Model (NICAM-TM) confirmed the validity of the bias-correction values evaluated over airports in limited areas. In low latitudes in the upper MT region (398-287 hPa), however, TIR CO2 data in northern summer were overcorrected by these bias-correction values; this is because the bias-correction values were determined using comparisons mainly over airports in

Investigation of mesoscale meteorological phenomena as observed by geostationary satellite

NASA Technical Reports Server (NTRS)

Brundidge, K. C.

1982-01-01

Satellite imagery plus conventional synoptic observations were used to examine three mesoscale systems recently observed by the GOES-EAST satellite. The three systems are an arc cloud complex (ACC), mountain lee wave clouds and cloud streets parallel to the wind shear. Possible gravity-wave activity is apparent in all three cases. Of particular interest is the ACC because of its ability to interact with other mesoscale phenomena to produce or enhance convection.

Lunar occultation of Saturn. IV - Astrometric results from observations of the satellites

NASA Technical Reports Server (NTRS)

Dunham, D. W.; Elliot, J. L.

1978-01-01

The method of determining local lunar limb slopes, and the consequent time scale needed for diameter studies, from accurate occultation timings at two nearby telescopes is described. Results for photoelectric observations made at Mauna Kea Observatory during the occultation of Saturn's satellites on March 30, 1974, are discussed. Analysis of all observations of occultations of Saturn's satellites during 1974 indicates possible errors in the ephemerides of Saturn and its satellites.

The IAU Com. 20 Natural Planetary Satellites Data Base of astrometric observations

NASA Astrophysics Data System (ADS)

Emelianov, N.; Arlot, J. E.

2005-08-01

The need of astrometric observations for the fit the dynamical models of the natural satellites appears in the 1970's when the computers were able to analyse large sets of data. Then, theoreticians started to search for numerous data from the observers. The IAU commission 20 encouraged then the creation of a Data Center, under the responsibility of the Working Group on Natural satellites, to gather the data and make then available for the community. Today, the data center gathers near 90 existing data, available on the web site of IMCCE (Paris) with a mirror at SAI (Moscow). The Web address is: www.imcce.fr/nsdc The available data are, for the satellites of: -Mars: 4558 observations (1877-1988) -Jupiter: Galilean: 12000 observations (1891-2001); inner: 730 (1954-2000); outer: 3300 for J6 to J13 (1894-2003) and 1250 from J17 to fainters (1975-2004) -Saturn: main: 48 000 observations (1874-2001); inner and coorbital:1058 (1966-2002); outer: 705 observations of Phoebe (1904-2004) and 505 of the fainters (2000-2005) -Uranus: main: 12 591 observations (1982-2003); faint: 130 (1994) -Neptune: 1384 observations of Triton (1989-2001); 495 of Nereide (1949-2004); 200 of the outers (1984-2004) and 83 of the inners (1991-1997) -Pluto and asteroids: under construction We gather also 21213 eclipses and occultations (1652-1983), 542 mutual events (1985-1991) of the Galilean satellites and 66 mutual events (1995-1996) for the Saturnian satellites. This data base is made possible thanks to the help of R. Vieira-Martins, C. Veiga (Rio de Janeiro observatory) who provides data as recommended by the Data Center, G. Williams (MPC) who sends the observations of the faint outer satellites of the giant planets gathered as asteroidal observations and D. Pascu who made efforts to complete the reduction of his data.

Astrometric observations of Saturn's satellites from McDonald Observatory, 1972

NASA Technical Reports Server (NTRS)

Abbot, R. I.; Mulholland, J. D.; Shelus, P. J.

1975-01-01

Observations of Saturn's satellites have been reduced by means of secondary reference stars obtained by reduction of Palomar Sky Survey plates. This involved the use of 29 SAO stars and plate overlap technique to determine the coordinates of 59 fainter stars in the satellite field. Fourteen plate constants were determined for each of the two PSS plates. Comparison of two plate measurement and reduction techniques on the satellite measures appears to demonstrate the existence of a serious background gradient effect and the utility of microdensitometry to eliminate this error source in positional determinations of close satellites.

Thermospheric density estimation from SLR observations of LEO satellites - A case study with the ANDE-Pollux satellite

NASA Astrophysics Data System (ADS)

Blossfeld, M.; Schmidt, M.; Erdogan, E.

2016-12-01

The thermospheric neutral density plays a crucial role within the equation of motion of Earth orbiting objects since drag, lift or side forces are one of the largest non-gravitational perturbations acting on the satellite. Precise Orbit Determination (POD) methods can be used to estimate thermospheric density variations from measured orbit determinations. One method which provides highly accurate measurements of the satellite position is Satellite Laser Ranging (SLR). Within the POD process, scaling factors are estimated frequently. These scaling factors can be either used for the scaling of the so called satellite-specific drag (ballistic) coefficients or the integrated thermospheric neutral density. We present a method for analytically model the drag coefficient based on a couple of physical assumptions and key parameters. In this paper, we investigate the possibility to use SLR observations to the very low Earth orbiting satellite ANDE-Pollux (approximately at 350km altitude) to determine scaling factors for different a priori thermospheric density models. We perform a POD for ANDE-Pollux covering 49 days between August 2009 and September 2009 which means the time span containing the largest number of observations during the short lifetime of the satellite. Finally, we compare the obtained scaled thermospheric densities w.r.t. each other

Validation of GOSAT XCO2 and XCH4 retrieved by PPDF-S method and evaluation of sensitivity of aerosols to gas concentrations

NASA Astrophysics Data System (ADS)

Iwasaki, C.; Imasu, R.; Bril, A.; Yokota, T.; Yoshida, Y.; Morino, I.; Oshchepkov, S.; Rokotyan, N.; Zakharov, V.; Gribanov, K.

2017-12-01

Photon path length probability density function-Simultaneous (PPDF-S) method is one of effective algorithms for retrieving column-averaged concentrations of carbon dioxide (XCO2) and methane (XCH4) from Greenhouse gases Observing SATellite (GOSAT) spectra in Short Wavelength InfraRed (SWIR) [Oshchepkov et al., 2013]. In this study, we validated XCO2 and XCH4 retrieved by the PPDF-S method through comparison with the Total Carbon Column Observing Network (TCCON) data [Wunch et al., 2011] from 26 sites including additional site of the Ural Atmospheric Station at Kourovka [57.038°N and 59.545°E], Russia. Validation results using TCCON data show that bias and its standard deviation of PPDF-S data are respectively 0.48 and 2.10 ppm for XCO2, and -0.73 and 15.77 ppb for XCH4. The results for XCO2 are almost identical with those of Iwasaki et al. [2017] for which the validation data were limited at selected 11 sites. However, the bias of XCH4 shows opposite sign against that of Iwasaki et al. [2017]. Furthermore, the data at Kourouvka showed different features particularly for XCH4. In order to investigate the causes for the differences, we have carried out simulation studies mainly focusing on the effects of aerosols which modify the light path length of solar radiation [O'Brien and Rayner, 2002; Aben et al., 2007; Oshchepkov et al., 2008]. Based on the simulation studies using multiple radiation transfer code based on Discrete Ordinate Method (DOM), Polarization System for Transfer of Atmospheric Radiation3 (Pstar3) [Ota et al., 2010], sensitivity of aerosols to gas concentrations was examined.

VLBI observations to the APOD satellite

NASA Astrophysics Data System (ADS)

Sun, Jing; Tang, Geshi; Shu, Fengchun; Li, Xie; Liu, Shushi; Cao, Jianfeng; Hellerschmied, Andreas; Böhm, Johannes; McCallum, Lucia; McCallum, Jamie; Lovell, Jim; Haas, Rüdiger; Neidhardt, Alexander; Lu, Weitao; Han, Songtao; Ren, Tianpeng; Chen, Lue; Wang, Mei; Ping, Jinsong

2018-02-01

The APOD (Atmospheric density detection and Precise Orbit Determination) is the first LEO (Low Earth Orbit) satellite in orbit co-located with a dual-frequency GNSS (GPS/BD) receiver, an SLR reflector, and a VLBI X/S dual band beacon. From the overlap statistics between consecutive solution arcs and the independent validation by SLR measurements, the orbit position deviation was below 10 cm before the on-board GNSS receiver got partially operational. In this paper, the focus is on the VLBI observations to the LEO satellite from multiple geodetic VLBI radio telescopes, since this is the first implementation of a dedicated VLBI transmitter in low Earth orbit. The practical problems of tracking a fast moving spacecraft with current VLBI ground infrastructure were solved and strong interferometric fringes were obtained by cross-correlation of APOD carrier and DOR (Differential One-way Ranging) signals. The precision in X-band time delay derived from 0.1 s integration time of the correlator output is on the level of 0.1 ns. The APOD observations demonstrate encouraging prospects of co-location of multiple space geodetic techniques in space, as a first prototype.

Comparison of Satellite Observations of Nitrogen Dioxide to Surface Monitor Nitrogen Dioxide Concentration

NASA Technical Reports Server (NTRS)

Kleb, Mary M.; Pippin, Margaret R.; Pierce, R. Bradley; Neil, Doreen O.; Lingenfelser, Gretchen; Szykman, James J.

2006-01-01

Nitrogen dioxide is one of the U. S. EPA s criteria pollutants, and one of the main ingredients needed for the production of ground-level ozone. Both ozone and nitrogen dioxide cause severe public health problems. Existing satellites have begun to produce observational data sets for nitrogen dioxide. Under NASAs Earth Science Applications Program, we examined the relationship between satellite observations and surface monitor observations of this air pollutant to examine if the satellite data can be used to facilitate a more capable and integrated observing network. This report provides a comparison of satellite tropospheric column nitrogen dioxide to surface monitor nitrogen dioxide concentration for the period from September 1996 through August 1997 at more than 300 individual locations in the continental US. We found that the spatial resolution and observation time of the satellite did not capture the variability of this pollutant as measured at ground level. The tools and processes developed to conduct this study will be applied to the analysis of advanced satellite observations. One advanced instrument has significantly better spatial resolution than the measurements studied here and operates with an afternoon overpass time, providing a more representative distribution for once-per-day sampling of this photochemically active atmospheric constituent.

Assessment of Developing Intensity Duration Frequency Curves using Satellite Observations (Case Study)

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.

GreenHouse gas Observations of the Stratosphere and Troposphere (GHOST): Deployment of a Novel Shortwave Infrared Spectrometer On Board the NASA Global Hawk Unmanned Aerial Vehicle

NASA Astrophysics Data System (ADS)

Humpage, N.; Boesch, H.; Palmer, P. I.; Parr-Burman, P.; Vick, A.; Bezawada, N.; Black, M.; Born, A.; Gao, X.; Pearson, D.; Samara-Ratna, P.; Strachan, J.; Wells, M.

2015-12-01

GHOST is a novel, compact shortwave infrared spectrometer, designed for remote sensing of tropospheric columns of greenhouse gases (GHGs) over the ocean from an unmanned aircraft. This is achieved by observing solar radiation at high spectral resolution which has been directly reflected by the ocean surface. The GHOST system has been specifically designed and built to address the following science objectives: 1) testing of atmospheric transport models; 2) validation of GHG column observations over oceans obtained using polar orbiting satellites; and 3) complement in-situ tropopause transition layer observations from other instruments. During January and February 2015 GHOST successfully underwent rigorous environmental testing and was installed on board the Northrop Grumman Global Hawk N872NA, an unmanned aircraft operated by NASA from the Armstrong Flight Research Centre at Edwards Air Force Base, California. Here, we present first results from two Global Hawk flights which took place in March 2015 as part of the CAST-ATTREX campaign. The science flights comprised long, approximately north-south transects over the eastern Pacific Ocean, providing an opportunity to observe spatial trends in GHG column concentrations on regional scale. The second science flight on 10th March 2015 coincided with overpasses from both the NASA OCO-2 (Orbiting Carbon Observatory) and the JAXA GOSAT (Greenhouse gases Observing SATellite) satellites, enabling inter-comparison of the GHOST results with total column observations from both satellites. A TCCON (Total Carbon Column Observing Network) station was also operational at Edwards during the two flights, allowing the GHOST observations to be validated against ground based total column measurements of GHGs.

Advances in using satellite altimetry to observe storm surge

NASA Astrophysics Data System (ADS)

Han, Guoqi

2017-04-01

Storm surges are the major cause for coastal flooding, resulting in catastrophic damage to properties and loss of life in coastal communities. Thus it is important to utilize new technology to enhance our capabilities of observing storm surges and ultimately to improve our capacity for forecasting storm surges and mitigating damage and loss. In this talk we first review traditional methods of monitoring storm surges. We then provide examples of storm surges observed by nadir satellite altimetry, during Hurricane Sandy and Igor, as well as typhoon and cyclone events. We further evaluate satellite results against tide-gauge data and explain storm surge features. Finally, we discuss the potential of a wide-swath altimetry mission, the Surface Water and Ocean Topography (SWOT), for observing storm surges.

Remote Observing with the Keck Telescope Using the ACTS Satellite

NASA Technical Reports Server (NTRS)

Cohen, Judy; Shopbell, Patrick; Bergman, Larry

1998-01-01

As a technical demonstration project for the NASA Advanced Communications Technology Satellite (ACTS), we have implemented remote observing on the 10-meter Keck II telescope on Mauna Kea in Hawaii from the California Institute of Technology campus in Pasadena. The data connection consists of optical fiber networks in Hawaii and California, connecting the end-points to high data rate (HDR) ACTS satellite antennae at JPL in Pasadena and at the Tripler Army Medical Center in Honolulu. The terrestrial fiber networks run the asynchronous transfer mode (ATM) protocol at DS-3 (45 Mbit/sec) speeds, providing ample bandwidth to enable remote observing with a software environment identical to that used for on-site observing in Hawaii. This experiment has explored the data requirements of remote observing with a modern research telescope and large-format detector arrays. While the maximum burst data rates are lower than those required for many other applications (e.g., HDTV), the network reliability and data integrity requirements are critical. As we show in this report, the former issue particularly may be the greatest challenge for satellite networks for this class of application. We have also experimented with the portability of standard TCP/IP applications to satellite networks, demonstrating the need for alternative TCP congestion algorithms and minimization of bit error rates (BER). Reliability issues aside, we have demonstrated that true remote observing over high-speed networks provides several important advantages over standard observing paradigms. Technical advantages of the high-speed network access include more rapid download of data to a user's home institution and the opportunity for alternative communication facilities between members of an observing team, such as audio- and videoconferencing.

Outline of the survey on the development of earth observation satellites

NASA Technical Reports Server (NTRS)

1977-01-01

An independent earth observation system with land and sea satellites to be developed by Japan is described. Visible and infrared radiometers, microwave radiometers, microwave scattermeters, synthetic aperture radar, and laser sensors are among the instrumentation discussed. Triaxial attitude control, basic technology common to sea and land observation satellites as well as land data analytical technology developed for U.S. LANDSAT data are reviewed.

JEOS. The JANUS earth observation satellite

NASA Astrophysics Data System (ADS)

Molette, P.; Jouan, J.

The JANUS multimission platform has been designed to minimize the cost of the satellite (by a maximum reuse of equipment from other proprogrammes) and of its associated launch by Aŕiane (by a piggy-back configuration optimized for Ariane 4). The paper describes the application of the JANUS platform to an Earth observation mission with the objective to provide a given country with a permanent monitoring of its earth resources by exploitation of spaceborne imagery. According to this objective, and to minimize the overall system and operational cost, the JANUS Earth Observation Satellite (JEOS) will provide a limited coverage with real time transmission of image data, thus avoiding need for on-board storage and simplifying operations. The JEOS operates on a low earth, near polar sun synchronous orbit. Launched in a piggy-back configuration on Ariane 4, with a SPOT or ERS spacecraft, it reaches its operational orbit after a drift orbit of a few weeks maximum. In its operational mode, the JEOS is 3-axis stabilised, earth pointed. After presentation of the platform, the paper describes the solid state push-broom camera which is composed of four optical lenses mounted on a highly stable optical bench. Each lens includes an optics system, reused from an on-going development, and two CCD linear arrays of detectors. The camera provides four registered channels in visible and near IR bands. The whole optical bench is supported by a rotating mechanism which allows rotation of the optical axis in the across-track direction. The JEOS typical performance for a 700 km altitude is then summarized: spatial resolution 30 m, swath width 120 km, off-track capability 325 km,… The payload data handling and transmission electronics, derived from the French SPOT satellite, realizes the processing, formatting, and transmission to the ground; this allows reuse of the standard SPOT receiving stations. The camera is only operated when the spacecraft is within the visibility of the ground

Asian Dust Weather Categorization with Satellite and Surface Observations

NASA Technical Reports Server (NTRS)

Lin, Tang-Huang; Hsu, N. Christina; Tsay, Si-Chee; Huang, Shih-Jen

2011-01-01

This study categorizes various dust weather types by means of satellite remote sensing over central Asia. Airborne dust particles can be identified by satellite remote sensing because of the different optical properties exhibited by coarse and fine particles (i.e. varying particle sizes). If a correlation can be established between the retrieved aerosol optical properties and surface visibility, the intensity of dust weather can be more effectively and consistently discerned using satellite rather than surface observations. In this article, datasets consisting of collocated products from Moderate Resolution Imaging Spectroradiometer Aqua and surface measurements are analysed. The results indicate an exponential relationship between the surface visibility and the satellite-retrieved aerosol optical depth, which is subsequently used to categorize the dust weather. The satellite-derived spatial frequency distributions in the dust weather types are consistent with China s weather station reports during 2003, indicating that dust weather classification using satellite data is highly feasible. Although the period during the springtime from 2004 to 2007 may be not sufficient for statistical significance, our results reveal an increasing tendency in both intensity and frequency of dust weather over central Asia during this time period.

GOSAT CO2 retrieval results using TANSO-CAI aerosol information over East Asia

NASA Astrophysics Data System (ADS)

KIM, M.; Kim, W.; Jung, Y.; Lee, S.; Kim, J.; Lee, H.; Boesch, H.; Goo, T. Y.

2015-12-01

In the satellite remote sensing of CO2, incorrect aerosol information could induce large errors as previous studies suggested. Many factors, such as, aerosol type, wavelength dependency of AOD, aerosol polarization effect and etc. have been main error sources. Due to these aerosol effects, large number of data retrieved are screened out in quality control, or retrieval errors tend to increase if not screened out, especially in East Asia where aerosol concentrations are fairly high. To reduce these aerosol induced errors, a CO2 retrieval algorithm using the simultaneous TANSO-CAI aerosol information is developed. This algorithm adopts AOD and aerosol type information as a priori information from the CAI aerosol retrieval algorithm. The CO2 retrieval algorithm based on optimal estimation method and VLIDORT, a vector discrete ordinate radiative transfer model. The CO2 algorithm, developed with various state vectors to find accurate CO2 concentration, shows reasonable results when compared with other dataset. This study concentrates on the validation of retrieved results with the ground-based TCCON measurements in East Asia and the comparison with the previous retrieval from ACOS, NIES, and UoL. Although, the retrieved CO2 concentration is lower than previous results by ppm's, it shows similar trend and high correlation with previous results. Retrieved data and TCCON measurements data are compared at three stations of Tsukuba, Saga, Anmyeondo in East Asia, with the collocation criteria of ±2°in latitude/longitude and ±1 hours of GOSAT passing time. Compared results also show similar trend with good correlation. Based on the TCCON comparison results, bias correction equation is calculated and applied to the East Asia data.

Satellite Observations of Tropospheric Ammonia

NASA Astrophysics Data System (ADS)

Shephard, M. W.; Luo, M.; Rinsland, C. P.; Cady-Pereira, K. E.; Beer, R.; Pinder, R. W.; Henze, D.; Payne, V. H.; Clough, S.; Rodgers, C. D.; Osterman, G. B.; Bowman, K. W.; Worden, H. M.

2008-12-01

Global high-spectral resolution (0.06 cm-1) nadir measurements from TES-Aura enable the simultaneous retrieval of a number of tropospheric pollutants and trace gases in addition to the TES standard operationally retrieved products (e.g. carbon monoxide, ozone). Ammonia (NH3) is one of the additional species that can be retrieved in conjunction with the TES standard products, and is important for local, regional, and global tropospheric chemistry studies. Ammonia emissions contribute significantly to several well-known environmental problems, yet the magnitude and seasonal/spatial variability of the emissions are poorly constrained. In the atmosphere, an important fraction of fine particulate matter is composed of ammonium nitrate and ammonium sulfate. These particles are statistically associated with health impacts. When deposited to ecosystems in excess, nitrogen, including ammonia can cause nutrient imbalances, change in ecosystem species composition, eutrophication, algal blooms and hypoxia. Ammonia is also challenging to measure in-situ. Observations of surface concentrations are rare and are particularly sparse in North America. Satellite observations of ammonia are therefore highly desirable. We recently demonstrated that tropospheric ammonia is detectable in the TES spectra and presented some corresponding preliminary retrievals over a very limited range of conditions (Beer et al., 2008). Presented here are results that expand upon these initial TES ammonia retrievals in order to evaluate/validate the retrieval results utilizing in-situ surface observations (e.g. LADCO, CASTNet, EPA /NC State) and chemical models (e.g. GEOS-Chem and CMAQ). We also present retrievals over regions of interest that have the potential to help further understand air quality and the active nitrogen cycle. Beer, R., M. W. Shephard, S. S. Kulawik, S. A. Clough, A. Eldering, K. W. Bowman, S. P. Sander, B. M. Fisher, V. H. Payne, M. Luo, G. B. Osterman, and J. R. Worden, First

First ISON observations for satellite conjunction analysis in the Western Hemisphere

NASA Astrophysics Data System (ADS)

Zalles, R.; Molotov, I.; Kokina, T.; Zolotov, V.; Condori, R.

2018-01-01

In this paper we report on observations of a pair of approaching space objects in the beginning of June 2016, observed jointly by the Tarija Observatory in Bolivia and the Mexican observatory of Sinaloa University in Cosala in the context of the ISON collaboration. These objects were the STAR ONE C1 (2007-056A) active satellite in GEO position 65\\ deg west, and the passive satellite LES 6 (1968-081D). The large number of measurements obtained in a few nights allowed a precise orbit reconstruction. The passive satellite LES 6 (with a brigtness amplitude variation of 3 magnitudes) was too faint for the small aperture of the Cosala telescope.

Landsat—Earth observation satellites

USGS Publications Warehouse

,

2015-11-25

Since 1972, Landsat satellites have continuously acquired space-based images of the Earth’s land surface, providing data that serve as valuable resources for land use/land change research. The data are useful to a number of applications including forestry, agriculture, geology, regional planning, and education. Landsat is a joint effort of the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). NASA develops remote sensing instruments and the spacecraft, then launches and validates the performance of the instruments and satellites. The USGS then assumes ownership and operation of the satellites, in addition to managing all ground reception, data archiving, product generation, and data distribution. The result of this program is an unprecedented continuing record of natural and human-induced changes on the global landscape.

Observational and Dynamical Wave Climatologies. VOS vs Satellite Data

NASA Astrophysics Data System (ADS)

Grigorieva, Victoria; Badulin, Sergei; Chernyshova, Anna

2013-04-01

The understanding physics of wind-driven waves is crucially important for fundamental science and practical applications. This is why experimental efforts are targeted at both getting reliable information on sea state and elaborating effective tools of the sea wave forecasting. The global Visual Wave Observations and satellite data from the GLOBWAVE project of the European Space Agency are analyzed in the context of these two viewpoints. Within the first "observational" aspect we re-analyze conventional climatologies of all basic wave parameters for the last decades [5]. An alternative "dynamical" climatology is introduced as a tool of prediction of dynamical features of sea waves on global scales. The features of wave dynamics are studied in terms of one-parametric dependencies of wave heights on wave periods following the theoretical concept of self-similar wind-driven seas [3, 1, 4] and recently proposed approach to analysis of Voluntary Observing Ship (VOS) data [2]. Traditional "observational" climatologies based on VOS and satellite data collections demonstrate extremely consistent pictures for significant wave heights and dominant periods. On the other hand, collocated satellite and VOS data show significant differences in wave heights, wind speeds and, especially, in wave periods. Uncertainties of visual wave observations can explain these differences only partially. We see the key reason of this inconsistency in the methods of satellite data processing which are based on formal application of data interpolation methods rather than on up-to-date physics of wind-driven waves. The problem is considered within the alternative climatology approach where dynamical criteria of wave height-to-period linkage are used for retrieving wave periods and constructing physically consistent dynamical climatology. The key dynamical parameter - exponent R of one-parametric dependence Hs ~ TR shows dramatically less pronounced latitudinal dependence as compared to observed Hs

Role of light satellites in the high-resolution Earth observation domain

NASA Astrophysics Data System (ADS)

Fishman, Moshe

1999-12-01

Current 'classic' applications using and exploring space based earth imagery are exclusive, narrow niche tailored, expensive and hardly accessible. On the other side new, inexpensive and widely used 'consumable' applications will be only developed concurrently to the availability of appropriate imagery allowing that process. A part of these applications can be imagined today, like WWW based 'virtual tourism' or news media, but the history of technological, cultural and entertainment evolution teaches us that most of future applications are unpredictable -- they emerge together with the platforms enabling their appearance. The only thing, which can be ultimately stated, is that the definitive condition for such applications is the availability of the proper imagery platform providing low cost, high resolution, large area, quick response, simple accessibility and quick dissemination of the raw picture. This platform is a constellation of Earth Observation satellites. Up to 1995 the Space Based High Resolution Earth Observation Domain was dominated by heavy, super-expensive and very inflexible birds. The launch of Israeli OFEQ-3 Satellite by MBT Division of Israel Aircraft Industries (IAI) marked the entrance to new era of light, smart and cheap Low Earth Orbited Imaging satellites. The Earth Resource Observation System (EROS) initiated by West Indian Space, is based on OFEQ class Satellites design and it is capable to gather visual data of Earth Surface both at high resolution and large image capacity. The main attributes, derived from its compact design, low weight and sophisticated logic and which convert the EROS Satellite to valuable and productive system, are discussed. The major advantages of Light Satellites in High Resolution Earth Observation Domain are presented and WIS guidelines featuring the next generation of LEO Imaging Systems are included.

The Value of Photographic Observations in Improving the Accuracy of Satellite Orbits.

DTIC Science & Technology

1982-02-01

cameras in the years 1971 -3 have recently become available, particularly of the balloon-satellite Explorer 19, from the observing stations at Riga...from the Russian AFU-75 cameras in the years 1971 -1973 have recently become available, particularly of the balloon- satellite Explorer 19, from the...large numbers of observations frum the Russian AFU-75 cameras have become available, covering the years 1971 -3. The observations, made during the

Background concentrations for high resolution satellite observing systems of methane

NASA Astrophysics Data System (ADS)

Benmergui, J. S.; Propp, A. M.; Turner, A. J.; Wofsy, S. C.

2017-12-01

Emerging satellite technologies promise to measure total column dry-air mole fractions of methane (XCH4) at resolutions on the order of a kilometer. XCH4 is linearly related to regional methane emissions through enhancements in the mixed layer, giving these satellites the ability to constrain emissions at unprecedented resolution. However, XCH4 is also sensitive to variability in transport of upwind concentrations (the "background concentration"). Variations in the background concentration are caused by synoptic scale transport in both the free troposphere and the stratosphere, as well as the rate of methane oxidation. Misspecification of the background concentration is aliased onto retrieved emissions as bias. This work explores several methods of specifying the background concentration for high resolution satellite observations of XCH4. We conduct observing system simulation experiments (OSSEs) that simulate the retrieval of emissions in the Barnett Shale using observations from a 1.33 km resolution XCH4 imaging satellite. We test background concentrations defined (1) from an external continental-scale model, (2) using pixels along the edge of the image as a boundary value, (3) using differences between adjacent pixels, and (4) using differences between the same pixel separated by one hour in time. We measure success using the accuracy of the retrieval, the potential for bias induced by misspecification of the background, and the computational expedience of the method. Pathological scenarios are given to each method.

Principle characteristics of the National Earth Observation Satellite. Project SPOT

NASA Technical Reports Server (NTRS)

Cazenave, M.

1977-01-01

A recent meeting of the Economic and Social Committee examined the programs and means currently being implemented by France in the field in the field of space research and industry which could bring about fast results. This was prompted by man's desire to insure rational resource management of his planet and by man's awareness of the definite contribution that space observation can make to this field of research. Through discussion, the Economic and Social Committee has approved the plan for creating an earth observation satellite. A detailed discussion of the principle characteristics of this earth observation satellite include the objectives, the orbit, characteristics and operations of the platform, maintenance, attitude measurement, the power available and many other characteristics.

US EPA: A USER AGENCY PERSPECTIVE ON POLAR SATELLITE OBSERVATIONS

EPA Science Inventory

The Agency uses satellite sensor observations in its work on measuring, monitoring and modeling the environment and human health. It generates observations in collaboration with states, local and regional governments, tribes and others, and is a consumer of observations from a v...

Multi-Satellite Orbit Determination Using Interferometric Observables with RF Localization Applications

NASA Astrophysics Data System (ADS)

Geeraert, Jeroen L.

Very long baseline interferometry (VLBI) specifically same-beam interferometry (SBI), and dual-satellite geolocation are two fields of research not previously connected. This is due to the different application of each field, SBI is used for relative interplanetary navigation of two satellites while dual-satellite geolocation is used to locate the source of a radio frequency (RF) signal. In this dissertation however, we leverage both fields to create a novel method for multi-satellite orbit determination (OD) using time difference of arrival (TDOA) and frequency difference of arrival (FDOA) measurements. The measurements are double differenced between the satellites and the stations, in so doing, many of the common errors are canceled which can significantly improve measurement precision. Provided with this novel OD technique, the observability is first analyzed to determine the benefits and limitations of this method. In all but a few scenarios the measurements successfully reduce the covariance when examining the Cramer-Rao Lower Bound (CRLB). Reduced observability is encountered with geostationary satellites as their motion with respect to the stations is limited, especially when only one baseline is used. However, when using satellite pairs with greater relative motion with respect to the stations, even satellites that are close to, but not exactly in a geostationary orbit can be estimated accurately. We find that in a strong majority of cases the OD technique provides lower uncertainties and solutions far more accurate than using conventional OD observables such as range and range-rate while also not being affected by common errors and biases. We specifically examine GEO-GEO, GEO-MEO, and GEO-LEO dual-satellite estimation cases. The work is further extended by developing a relative navigation scenario where the chief satellite is assumed to have perfect knowledge, or some small amount of uncertainty considered but not estimated, while estimating the deputy

Co-ordination of satellite and data programs: The committee on earth observation satellites' approach

NASA Astrophysics Data System (ADS)

Embleton, B. J. J.; Kingwell, J.

1997-01-01

Every year, an average of eight new civilian remote sensing satellite missions are launched. Cumulatively, over 250 such missions, each with a cost equivalent in current value to between US 100 million to US 1000 million, have been sponsored by space agencies in perhaps two dozen countries. These missions produce data and information products which are vital for informed decision making all over the world, on matters relating to natural resource exploitation, health and safety, sustainable national development, infrastructure planning, and a host of other applications. By contributing to better scientific understanding of global changes in the atmosphere, land surface, oceans and ice caps, these silently orbiting sentinels in the sky make it possible for governments and industries to make wiser environmental policy decisions and support the economic development needs of humanity. The international Committee on Earth Observation Satellites (CEOS) is the premier world body for co-ordinating and planning civilian satellite missions for Earth observation. Through its technical working groups and special task teams, it endeavours to: • maximise the international benefits from Earth observation satellites; and • harmonise practice in calibration, validation, data management and information systems for Earth observation. CEOS encompasses not only space agencies (data providers), but also the great international scientific and operational programs which rely on Earth science data from space. The user organisations affiliated with CEOS, together with the mission operators, attempt to reconcile user needs with the complex set of considerations — including national interests, cost, schedule — which affect the undertaking of space missions. Without such an internationally co-ordinated consensual approach, there is a much greater risk of waste through duplication, and of missed opportunity, or through the absence of measurements of some vital physical or biological

Constraining methane emissions from the Indo-Gangetic Plains and South Asia using combined surface and satellite data

NASA Astrophysics Data System (ADS)

Ganesan, A.; Lunt, M. F.; Rigby, M. L.; Chatterjee, A.; Boesch, H.; Parker, R.; Prinn, R. G.; van der Schoot, M. V.; Krummel, P. B.; Tiwari, Y. K.; Mukai, H.; Machida, T.; Terao, Y.; Nomura, S.; Patra, P. K.

2015-12-01

We present an analysis of the regional methane (CH4) budget from South Asia, using new measurements and new modelling techniques. South Asia contains some of the largest anthropogenic CH4 sources in the world, mainly from rice agriculture and ruminants. However, emissions from this region have been highly uncertain largely due to insufficient constraints from atmospheric measurements. Compared to parts of the developed world, which have well-developed monitoring networks, South Asia is very under-sampled, particularly given its importance to the global CH4 budget. Over the past few years, data have been collected from a variety of surface sites around the region, ranging from in situ to flask-based sampling. We have used these data, in conjunction with column methane data from the GOSAT satellite, to quantify emissions at a regional scale. Using the Met Office's Lagrangian NAME model, we calculated sensitivities to surface fluxes at 12 km resolution, allowing us to simulate the high-resolution impacts of emissions on concentrations. In addition, we used a newly developed hierarchical Bayesian inverse estimation scheme to estimate regional fluxes over the period of 2012-2014 in addition to ancillary "hyper-parameters" that characterize uncertainties in the system. Through this novel approach, we have characterized the effect of "aggregation" errors, model uncertainties as well as the effects of correlated errors when using regional measurement networks. We have also assessed the effects of biases on the GOSAT CH4 retrievals, which has been made possible for the first time for this region through the expanded surface measurements. In this talk, we will discuss a) regional CH4 fluxes from South Asia, with a particular focus on the densely populated Indo-Gangetic Plains b) derived model uncertainties, including the effects of correlated errors c) the impacts of combining surface and satellite data for emissions estimation in regions where poor satellite validation

Improve observation-based ground-level ozone spatial distribution by compositing satellite and surface observations: A simulation experiment

NASA Astrophysics Data System (ADS)

Zhang, Yuzhong; Wang, Yuhang; Crawford, James; Cheng, Ye; Li, Jianfeng

2018-05-01

Obtaining the full spatial coverage of daily surface ozone fields is challenging because of the sparsity of the surface monitoring network and the difficulty in direct satellite retrievals of surface ozone. We propose an indirect satellite retrieval framework to utilize the information from satellite-measured column densities of tropospheric NO2 and CH2O, which are sensitive to the lower troposphere, to derive surface ozone fields. The method is applicable to upcoming geostationary satellites with high-quality NO2 and CH2O measurements. To prove the concept, we conduct a simulation experiment using a 3-D chemical transport model for July 2011 over the eastern US. The results show that a second order regression using both NO2 and CH2O column densities can be an effective predictor for daily maximum 8-h average ozone. Furthermore, this indirect retrieval approach is shown to be complementary to spatial interpolation of surface observations, especially in regions where the surface sites are sparse. Combining column observations of NO2 and CH2O with surface site measurements leads to an improved representation of surface ozone over simple kriging, increasing the R2 value from 0.53 to 0.64 at a surface site distance of 252 km. The improvements are even more significant with larger surface site distances. The simulation experiment suggests that the indirect satellite retrieval technique can potentially be a useful tool to derive the full spatial coverage of daily surface ozone fields if satellite observation uncertainty is moderate.

In situ statistical observations of EMIC waves by Arase satellite

NASA Astrophysics Data System (ADS)

Nomura, R.; Matsuoka, A.; Teramoto, M.; Nose, M.; Yoshizumi, M.; Fujimoto, A.; Shinohara, M.; Tanaka, Y.

2017-12-01

We present in situ statistical survey of electromagnetic ion cyclotron (EMIC) waves observed by Arase satellite from 3 March to 16 July 2017. We identified 64 events using the fluxgate magnetometer (MGF) on the satellite. The EMIC wave is the key phenomena to understand the loss dynamics of MeV-energy electrons in the radiation belt. We will show the radial and latitudinal dependence of the wave occurance rate and the wave parameters (frequency band, coherence, polarization, and ellipticity). Especially the EMIC waves observed at localized weak background magnetic field will be discussed for the wave excitation mechanism in the deep inner magnetosphere.

Comparisons of Radiative Flux Distributions from Satellite Observations and Global Models

NASA Astrophysics Data System (ADS)

Raschke, Ehrhard; Kinne, Stefan; Wild, Martin; Stackhouse, Paul; Rossow, Bill

2014-05-01

Radiative flux distributions at the top of the atmosphere (TOA) and at the surface are compared between typical data from satellite observations and from global modeling. Averages of CERES, ISCCP and SRB data-products (for the same 4-year period) represent satellite observations. Central values of IPCC-4AR output (over a 12-year period) represent global modeling. At TOA, differences are dominated by differences for cloud-effects, which are extracted from the differences between all-sky and clear-sky radiative flux products. As satellite data are considered as TOA reference, these differences document the poor representation of clouds in global modeling, especially for low altitude clouds over oceans. At the surface the differences, caused by the different cloud treatment are overlaid by a general offset. Satellite products suggest a ca 15Wm-2 stronger surface net-imbalance (and with it stronger precipitation). Since surface products of satellite and modeling are based on simulations and many assumptions, this difference has remained an open issue. BSRN surface monitoring is too short and too sparsely distributed for clear answers to provide a reliable basis for validation.

Handling the satellite inter-frequency biases in triple-frequency observations

NASA Astrophysics Data System (ADS)

Zhao, Lewen; Ye, Shirong; Song, Jia

2017-04-01

The new generation of GNSS satellites, including BDS, Galileo, modernized GPS, and GLONASS, transmit navigation sdata at more frequencies. Multi-frequency signals open new prospects for precise positioning, but satellite code and phase inter-frequency biases (IFB) induced by the third frequency need to be handled. Satellite code IFB can be corrected using products estimated by different strategies, the theoretical and numerical compatibility of these methods need to be proved. Furthermore, a new type of phase IFB, which changes with the relative sun-spacecraft-earth geometry, has been observed. It is necessary to investigate the cause and possible impacts of phase Time-variant IFB (TIFB). Therefore, we present systematic analysis to illustrate the relevancy between satellite clocks and phase TIFB, and compare the handling strategies of the code and phase IFB in triple-frequency positioning. First, the un-differenced L1/L2 satellite clock corrections considering the hardware delays are derived. And IFB induced by the dual-frequency satellite clocks to triple-frequency PPP model is detailed. The analysis shows that estimated satellite clocks actually contain the time-variant phase hardware delays, which can be compensated in L1/L2 ionosphere-free combinations. However, the time-variant hardware delays will lead to TIFB if the third frequency is used. Then, the methods used to correct the code and phase IFB are discussed. Standard point positioning (SPP) and precise point positioning (PPP) using BDS observations are carried out to validate the improvement of different IFB correction strategies. Experiments show that code IFB derived from DCB or geometry-free and ionosphere-free combination show an agreement of 0.3 ns for all satellites. Positioning results and error distribution with two different code IFB correcting strategies achieve similar tendency, which shows their substitutability. The original and wavelet filtered phase TIFB long-term series show significant

Satellite Observations for Detecting and Tracking Changes in Atmospheric Composition

EPA Science Inventory

The international scientific community's Integrated Global Atmosphere Chemistry Observation System report outlined a plan for ground-based, airborne and satellite Measurements, and models to integrate the observations into a 4-dimensional representation of the atmosphere (space a...

Study of the footprints of short-term variation in XCO2 observed by TCCON sites using NIES and FLEXPART atmospheric transport models

NASA Astrophysics Data System (ADS)

Belikov, Dmitry A.; Maksyutov, Shamil; Ganshin, Alexander; Zhuravlev, Ruslan; Deutscher, Nicholas M.; Wunch, Debra; Feist, Dietrich G.; Morino, Isamu; Parker, Robert J.; Strong, Kimberly; Yoshida, Yukio; Bril, Andrey; Oshchepkov, Sergey; Boesch, Hartmut; Dubey, Manvendra K.; Griffith, David; Hewson, Will; Kivi, Rigel; Mendonca, Joseph; Notholt, Justus; Schneider, Matthias; Sussmann, Ralf; Velazco, Voltaire A.; Aoki, Shuji

2017-01-01

The Total Carbon Column Observing Network (TCCON) is a network of ground-based Fourier transform spectrometers (FTSs) that record near-infrared (NIR) spectra of the sun. From these spectra, accurate and precise observations of CO2 column-averaged dry-air mole fractions (denoted XCO2) are retrieved. TCCON FTS observations have previously been used to validate satellite estimations of XCO2; however, our knowledge of the short-term spatial and temporal variations in XCO2 surrounding the TCCON sites is limited. In this work, we use the National Institute for Environmental Studies (NIES) Eulerian three-dimensional transport model and the FLEXPART (FLEXible PARTicle dispersion model) Lagrangian particle dispersion model (LPDM) to determine the footprints of short-term variations in XCO2 observed by operational, past, future and possible TCCON sites. We propose a footprint-based method for the collocation of satellite and TCCON XCO2 observations and estimate the performance of the method using the NIES model and five GOSAT (Greenhouse Gases Observing Satellite) XCO2 product data sets. Comparison of the proposed approach with a standard geographic method shows a higher number of collocation points and an average bias reduction up to 0.15 ppm for a subset of 16 stations for the period from January 2010 to January 2014. Case studies of the Darwin and Reunion Island sites reveal that when the footprint area is rather curved, non-uniform and significantly different from a geographical rectangular area, the differences between these approaches are more noticeable. This emphasises that the collocation is sensitive to local meteorological conditions and flux distributions.

Estimating Soil Moisture from Satellite Microwave Observations

NASA Technical Reports Server (NTRS)

Owe, M.; VandeGriend, A. A.; deJeu, R.; deVries, J.; Seyhan, E.

1998-01-01

Cooperative research in microwave remote sensing between the Hydrological Sciences Branch of the NASA Goddard Space Flight Center and the Earth Sciences Faculty of the Vrije Universiteit Amsterdam began with the Botswana Water and Energy Balance Experiment and has continued through a series of highly successful International Research Programs. The collaboration between these two research institutions has resulted in significant scientific achievements, most notably in the area of satellite-based microwave remote sensing of soil moisture. The Botswana Program was the first joint research initiative between these two institutions, and provided a unique data base which included historical data sets of Scanning Multifrequency Microwave Radiometer (SN4NM) data, climate information, and extensive soil moisture measurements over several large experimental sites in southeast Botswana. These data were the basis for the development of new approaches in physically-based inverse modelling of soil moisture from satellite microwave observations. Among the results from this study were quantitative estimates of vegetation transmission properties at microwave frequencies. A single polarization modelling approach which used horizontally polarized microwave observations combined with monthly composites of Normalized Difference Vegetation Index was developed, and yielded good results. After more precise field experimentation with a ground-based radiometer system, a dual-polarization approach was subsequently developed. This new approach realized significant improvements in soil moisture estimation by satellite. Results from the Botswana study were subsequently applied to a desertification monitoring study for the country of Spain within the framework of the European Community science research programs EFEDA and RESMEDES. A dual frequency approach with only microwave data was used for this application. The Microwave Polarization Difference Index (MPDI) was calculated from 37 GHz data

Decadal Record of Satellite Carbon Monoxide Observations

NASA Astrophysics Data System (ADS)

Worden, Helen; Deeter, Merritt; Frankenberg, Christian; George, Maya; Nichitiu, Florian; Worden, John; Aben, Ilse; Bowman, Kevin; Clerbaux, Cathy; Coheur, Pierre-Francois; de Laat, Jos; Warner, Juying; Drummond, James; Edwards, David; Gille, John; Hurtmans, Daniel; Ming, Luo; Martinez-Alonso, Sara; Massie, Steven; Pfister, Gabriele

2013-04-01

Atmospheric carbon monoxide (CO) distributions are controlled by anthropogenic emissions, biomass burning, chemical production, transport and oxidation by reaction with the hydroxyl radical (OH). Quantifying trends in CO is therefore important for understanding changes related to all of these contributions. Here we present a comprehensive record of satellite observations from 2000 through 2011 of total column CO using the available measurements from nadir-viewing thermal infrared instruments: MOPITT, AIRS, TES and IASI. We examine trends for CO in the Northern and Southern hemispheres along with regional trends for E. China, E. USA, Europe and India. Measurement and sampling methods for each of the instruments are discussed, and we show diagnostics for systematic errors in MOPITT trends. We find that all the satellite observations are consistent with a modest decreasing trend around -1%/year in total column CO over the Northern hemisphere for this time period. Decreasing trends in total CO column are observed for the United States, Europe and E. China with more than 2σ significance. For India, the trend is also decreasing, but smaller in magnitude and less significant. Decreasing trends in surface CO have also been observed from measurements in the U.S. and Europe. Although less information is available for surface CO in China, there is a decreasing trend reported for Beijing. Some of the interannual variability in the observations can be explained by global fire emissions, and there may be some evidence of the global financial crisis in late 2008 to early 2009. But the overall decrease needs further study to understand the implications for changes in anthropogenic emissions.

Comparing soil moisture memory in satellite observations and models

NASA Astrophysics Data System (ADS)

Stacke, Tobias; Hagemann, Stefan; Loew, Alexander

2013-04-01

A major obstacle to a correct parametrization of soil processes in large scale global land surface models is the lack of long term soil moisture observations for large parts of the globe. Currently, a compilation of soil moisture data derived from a range of satellites is released by the ESA Climate Change Initiative (ECV_SM). Comprising the period from 1978 until 2010, it provides the opportunity to compute climatological relevant statistics on a quasi-global scale and to compare these to the output of climate models. Our study is focused on the investigation of soil moisture memory in satellite observations and models. As a proxy for memory we compute the autocorrelation length (ACL) of the available satellite data and the uppermost soil layer of the models. Additional to the ECV_SM data, AMSR-E soil moisture is used as observational estimate. Simulated soil moisture fields are taken from ERA-Interim reanalysis and generated with the land surface model JSBACH, which was driven with quasi-observational meteorological forcing data. The satellite data show ACLs between one week and one month for the greater part of the land surface while the models simulate a longer memory of up to two months. Some pattern are similar in models and observations, e.g. a longer memory in the Sahel Zone and the Arabian Peninsula, but the models are not able to reproduce regions with a very short ACL of just a few days. If the long term seasonality is subtracted from the data the memory is strongly shortened, indicating the importance of seasonal variations for the memory in most regions. Furthermore, we analyze the change of soil moisture memory in the different soil layers of the models to investigate to which extent the surface soil moisture includes information about the whole soil column. A first analysis reveals that the ACL is increasing for deeper layers. However, its increase is stronger in the soil moisture anomaly than in its absolute values and the first even exceeds the

Using Deep Learning for Targeted Data Selection, Improving Satellite Observation Utilization for Model Initialization

NASA Astrophysics Data System (ADS)

Lee, Y. J.; Bonfanti, C. E.; Trailovic, L.; Etherton, B.; Govett, M.; Stewart, J.

2017-12-01

At present, a fraction of all satellite observations are ultimately used for model assimilation. The satellite data assimilation process is computationally expensive and data are often reduced in resolution to allow timely incorporation into the forecast. This problem is only exacerbated by the recent launch of Geostationary Operational Environmental Satellite (GOES)-16 satellite and future satellites providing several order of magnitude increase in data volume. At the NOAA Earth System Research Laboratory (ESRL) we are researching the use of machine learning the improve the initial selection of satellite data to be used in the model assimilation process. In particular, we are investigating the use of deep learning. Deep learning is being applied to many image processing and computer vision problems with great success. Through our research, we are using convolutional neural network to find and mark regions of interest (ROI) to lead to intelligent extraction of observations from satellite observation systems. These targeted observations will be used to improve the quality of data selected for model assimilation and ultimately improve the impact of satellite data on weather forecasts. Our preliminary efforts to identify the ROI's are focused in two areas: applying and comparing state-of-art convolutional neural network models using the analysis data from the National Center for Environmental Prediction (NCEP) Global Forecast System (GFS) weather model, and using these results as a starting point to optimize convolution neural network model for pattern recognition on the higher resolution water vapor data from GOES-WEST and other satellite. This presentation will provide an introduction to our convolutional neural network model to identify and process these ROI's, along with the challenges of data preparation, training the model, and parameter optimization.

On the geometric analysis and adjustment of optical satellite observations. M.S. Thesis

NASA Technical Reports Server (NTRS)

Tsimis, E.

1972-01-01

Satellite geodesy methods were catagorized into three divisions: geometric, dynamic, and mixed. These catagories furnish the basis for distinction between geometric and dynamic satellite geodesy. The dual adjustment, geometric analysis, and Cartesian coodinate determination are examined for two observing stations. Similar illustrations are given when more than two observing stations are used.

A Bayesian kriging approach for blending satellite and ground precipitation observations

USGS Publications Warehouse

Verdin, Andrew P.; Rajagopalan, Balaji; Kleiber, William; Funk, Christopher C.

2015-01-01

Drought and flood management practices require accurate estimates of precipitation. Gauge observations, however, are often sparse in regions with complicated terrain, clustered in valleys, and of poor quality. Consequently, the spatial extent of wet events is poorly represented. Satellite-derived precipitation data are an attractive alternative, though they tend to underestimate the magnitude of wet events due to their dependency on retrieval algorithms and the indirect relationship between satellite infrared observations and precipitation intensities. Here we offer a Bayesian kriging approach for blending precipitation gauge data and the Climate Hazards Group Infrared Precipitation satellite-derived precipitation estimates for Central America, Colombia, and Venezuela. First, the gauge observations are modeled as a linear function of satellite-derived estimates and any number of other variables—for this research we include elevation. Prior distributions are defined for all model parameters and the posterior distributions are obtained simultaneously via Markov chain Monte Carlo sampling. The posterior distributions of these parameters are required for spatial estimation, and thus are obtained prior to implementing the spatial kriging model. This functional framework is applied to model parameters obtained by sampling from the posterior distributions, and the residuals of the linear model are subject to a spatial kriging model. Consequently, the posterior distributions and uncertainties of the blended precipitation estimates are obtained. We demonstrate this method by applying it to pentadal and monthly total precipitation fields during 2009. The model's performance and its inherent ability to capture wet events are investigated. We show that this blending method significantly improves upon the satellite-derived estimates and is also competitive in its ability to represent wet events. This procedure also provides a means to estimate a full conditional distribution

SatCam: A mobile application for coordinated ground/satellite observation of clouds and validation of satellite-derived cloud mask products.

NASA Astrophysics Data System (ADS)

Gumley, L.; Parker, D.; Flynn, B.; Holz, R.; Marais, W.

2011-12-01

SatCam is an application for iOS devices that allows users to collect observations of local cloud and surface conditions in coordination with an overpass of the Terra, Aqua, or NPP satellites. SatCam allows users to acquire images of sky conditions and ground conditions at their location anywhere in the world using the built-in iPhone or iPod Touch camera at the same time that the satellite is passing overhead and viewing their location. Immediately after the sky and ground observations are acquired, the application asks the user to rate the level of cloudiness in the sky (Completely Clear, Mostly Clear, Partly Cloudy, Overcast). For the ground observation, the user selects their assessment of the surface conditions (Urban, Green Vegetation, Brown Vegetation, Desert, Snow, Water). The sky condition and surface condition selections are stored along with the date, time, and geographic location for the images, and the images are uploaded to a central server. When the MODIS (Terra and Aqua) or VIIRS (NPP) imagery acquired over the user location becomes available, a MODIS or VIIRS true color image centered at the user's location is delivered back to the SatCam application on the user's iOS device. SSEC also proposes to develop a community driven SatCam website where users can share their observations and assessments of satellite cloud products in a collaborative environment. SSEC is developing a server side data analysis system to ingest the SatCam user observations, apply quality control, analyze the sky images for cloud cover, and collocate the observations with MODIS and VIIRS satellite products (e.g., cloud mask). For each observation that is collocated with a satellite observation, the server will determine whether the user scored a "hit", meaning their sky observation and sky assessment matched the automated cloud mask obtained from the satellite observation. The hit rate will be an objective assessment of the accuracy of the user's sky observations. Users with

Evaluation of Long-Term Cloud-Resolving Model Simulations Using Satellite Radiance Observations and Multi-Frequency Satellite Simulators

NASA Technical Reports Server (NTRS)

Matsui, Toshihisa; Zeng, Xiping; Tao, Wei-Kuo; Masunaga, Hirohiko; Olson, William S.; Lang, Stephen

2008-01-01

This paper proposes a methodology known as the Tropical Rainfall Measuring Mission (TRMM) Triple-Sensor Three-step Evaluation Framework (T3EF) for the systematic evaluation of precipitating cloud types and microphysics in a cloud-resolving model (CRM). T3EF utilizes multi-frequency satellite simulators and novel statistics of multi-frequency radiance and backscattering signals observed from the TRMM satellite. Specifically, T3EF compares CRM and satellite observations in the form of combined probability distributions of precipitation radar (PR) reflectivity, polarization-corrected microwave brightness temperature (Tb), and infrared Tb to evaluate the candidate CRM. T3EF is used to evaluate the Goddard Cumulus Ensemble (GCE) model for cases involving the South China Sea Monsoon Experiment (SCSMEX) and Kwajalein Experiment (KWAJEX). This evaluation reveals that the GCE properly captures the satellite-measured frequencies of different precipitating cloud types in the SCSMEX case but underestimates the frequencies of deep convective and deep stratiform types in the KWAJEX case. Moreover, the GCE tends to simulate excessively large and abundant frozen condensates in deep convective clouds as inferred from the overestimated GCE-simulated radar reflectivities and microwave Tb depressions. Unveiling the detailed errors in the GCE s performance provides the best direction for model improvements.

Effects of cloud size and cloud particles on satellite-observed reflected brightness

NASA Technical Reports Server (NTRS)

Reynolds, D. W.; Mckee, T. B.; Danielson, K. S.

1978-01-01

Satellite observations allowed obtaining data on the visible brightness of cumulus clouds over South Park, Colorado, while aircraft observations were made in cloud to obtain the drop size distributions and liquid water content of the cloud. Attention is focused on evaluating the relationship between cloud brightness, horizontal dimension, and internal microphysical structure. A Monte Carlo cloud model for finite clouds was run using different distributions of drop sizes and numbers, while varying the cloud depth and width to determine how theory would predict what the satellite would view from its given location in space. Comparison of these results to the satellite observed reflectances is presented. Theoretical results are found to be in good agreement with observations. For clouds of optical thickness between 20 and 60, monitoring cloud brightness changes in clouds of uniform depth and variable width gives adequate information about a cloud's liquid water content. A cloud having a 10:1 width to depth ratio is almost reaching its maximum brightness for a specified optical thickness.

Challenges of coordinating global climate observations - Role of satellites in climate monitoring

NASA Astrophysics Data System (ADS)

Richter, C.

2017-12-01

Global observation of the Earth's atmosphere, ocean and land is essential for identifying climate variability and change, and for understanding their causes. Observation also provides data that are fundamental for evaluating, refining and initializing the models that predict how the climate system will vary over the months and seasons ahead, and that project how climate will change in the longer term under different assumptions concerning greenhouse gas emissions and other human influences. Long-term observational records have enabled the Intergovernmental Panel on Climate Change to deliver the message that warming of the global climate system is unequivocal. As the Earth's climate enters a new era, in which it is forced by human activities, as well as natural processes, it is critically important to sustain an observing system capable of detecting and documenting global climate variability and change over long periods of time. High-quality climate observations are required to assess the present state of the ocean, cryosphere, atmosphere and land and place them in context with the past. The global observing system for climate is not a single, centrally managed observing system. Rather, it is a composite "system of systems" comprising a set of climate-relevant observing, data-management, product-generation and data-distribution systems. Data from satellites underpin many of the Essential Climate Variables(ECVs), and their historic and contemporary archives are a key part of the global climate observing system. In general, the ECVs will be provided in the form of climate data records that are created by processing and archiving time series of satellite and in situ measurements. Early satellite data records are very valuable because they provide unique observations in many regions which were not otherwise observed during the 1970s and which can be assimilated in atmospheric reanalyses and so extend the satellite climate data records back in time.

Analytic Perturbation Method for Estimating Ground Flash Fraction from Satellite Lightning Observations

NASA Technical Reports Server (NTRS)

Koshak, William; Solakiewicz, Richard

2013-01-01

An analytic perturbation method is introduced for estimating the lightning ground flash fraction in a set of N lightning flashes observed by a satellite lightning mapper. The value of N is large, typically in the thousands, and the observations consist of the maximum optical group area produced by each flash. The method is tested using simulated observations that are based on Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS) data. National Lightning Detection NetworkTM (NLDN) data is used to determine the flash-type (ground or cloud) of the satellite-observed flashes, and provides the ground flash fraction truth for the simulation runs. It is found that the mean ground flash fraction retrieval errors are below 0.04 across the full range 0-1 under certain simulation conditions. In general, it is demonstrated that the retrieval errors depend on many factors (i.e., the number, N, of satellite observations, the magnitude of random and systematic measurement errors, and the number of samples used to form certain climate distributions employed in the model).

Overview of the Upper Atmosphere Research Satellite: Observations from 1991 to 2002

NASA Technical Reports Server (NTRS)

Jackman, Charles H.; Douglass, Anne R.

2003-01-01

The Upper Atmosphere Research Satellite (UARS) was launched in September 1991 by the Space Shuttle Discovery and continues to make relevant atmospheric measurements (as of October 2002). This successful satellite has fostered a better understanding of the middle atmospheric processes, especially those important in the control of ozone. Seven of the original ten instruments aboard the UARS are still functional and six instruments regularly make measurements. The UARS is in a stable observing configuration, in spite of experiencing several anomalies over its lifetime. It is expected that the UARS will overlap the Earth Observing System (EOS) Aura satellite (scheduled launch in January 2004) for several months before the end of the UARS mission.

Satellite microwave observations of a storm complex: A comparative analysis

NASA Technical Reports Server (NTRS)

Martin, D. W.

1985-01-01

The hypothesis that cold events correspond to a particular stage in a class of thunderstorms was tested. That class is a storms class which updrafts are: (1) strong, broad and moist, and (2) extend well above the freezing level. Condition (1) implies strong mesoscale forcing. Condition (2) implies a tall updraft or a relatively low freezing level. Such storms should have big, intense radar echoes and cold, fast-growing anvils. The thunderstorm events were analyzed by radar, rain gauge and GOES infrared observations. Radar was the starting point for detection and definition of the hypothesized thunderstorms. The radar signature is compared to the signature of the storm in rain gauge observations, satellite infrared images and satellite microwave images.

Observations of sea ice and icebergs from satellite radar altimeters

NASA Technical Reports Server (NTRS)

Rapley, C. G.

1984-01-01

Satellite radar altimeters can make useful contributions to the study of sea ice both by enhancing observations from other instruments and by providing a unique probe of ocean-ice interaction in the Marginal Ice Zone (MIZ). The problems, results and future potential of such observations are discussed.

Pre-seismic anomalies from optical satellite observations: a review

NASA Astrophysics Data System (ADS)

Jiao, Zhong-Hu; Zhao, Jing; Shan, Xinjian

2018-04-01

Detecting various anomalies using optical satellite data prior to strong earthquakes is key to understanding and forecasting earthquake activities because of its recognition of thermal-radiation-related phenomena in seismic preparation phases. Data from satellite observations serve as a powerful tool in monitoring earthquake preparation areas at a global scale and in a nearly real-time manner. Over the past several decades, many new different data sources have been utilized in this field, and progressive anomaly detection approaches have been developed. This paper reviews the progress and development of pre-seismic anomaly detection technology in this decade. First, precursor parameters, including parameters from the top of the atmosphere, in the atmosphere, and on the Earth's surface, are stated and discussed. Second, different anomaly detection methods, which are used to extract anomalous signals that probably indicate future seismic events, are presented. Finally, certain critical problems with the current research are highlighted, and new developing trends and perspectives for future work are discussed. The development of Earth observation satellites and anomaly detection algorithms can enrich available information sources, provide advanced tools for multilevel earthquake monitoring, and improve short- and medium-term forecasting, which play a large and growing role in pre-seismic anomaly detection research.

Solar neutron observations with ChubuSat-2 satellite

NASA Astrophysics Data System (ADS)

Yamaoka, Kazutaka

2016-07-01

Solar neutron observation is a key in understanding of ion accerelation mechanism in the Sun surface since neutrons are hardly affected by magnetic field around the Sun and intersteller mediums unlike charged particles. However, there was only a few tenth detections so far since its discovery in 1982. Actually SEDA-AP Fiber detector (FIB) onboard the International Space Station (ISS) was suffered from a high neutron background produced by the ISS itself. ChubuSat is a series of 50-kg class microsatellite jointly depeloped by universities (Nagoya university and Daido university) and aerospace companies at the Chubu area of central Japan. The ChubuSat-2 is the second ChubuSat following the ChubuSat-1 which was launched by Russian DNEPR rocket on November 6, 2014. It was selected as one of four piggyback payloads of the X-ray astronomy satellite ASTRO-H in 2014 summer, and will be launched by the H-IIA launch vehcles from from JAXA Tanegashima Space Center (TNSC) in February 2016. The ChubuSat-2 carries a mission instrument, radiation detector (RD). The main mission of ChubuSat-2 is devoted for monitoring neutrons and gamma-rays which can be background source for ASTRO-H celestrial observations with the RD. The mission also involves a function of solar neutron observations which were originally proposed by graduate students who join the leadership development program for space exploration and research, program for leading graduate schools at Nagoya University. The RD has a similar detection area and efficiency to those of the SEDA-AP FIB, but is expected to have lower backgrounthan the ISS thanks to much smaller mass of the micro-satellite. In this paper, we will describe details of ChubuSat-2 satellite and RD, and in-orbit performance of RD.

Model Evaluation with Multi-wavelength Satellite Observations Using a Neural Network

NASA Astrophysics Data System (ADS)

Kolassa, Jana; Jimenez, Carlos; Aires, Filipe

2013-04-01

A methodology has been developed to evaluate fields of modelled parameters against a set of satellite observations. The method employs a Neural Network (NN) to construct a statistical model capturing the relationship between the satellite observations and the parameter from a land surface model, in this case the Soil Moisture (SM). This statistical model is then used to estimate the parameter of interest from the set of satellite observations. These estimates are compared to the modelled parameter in order to detect local deviations indicating a possible problem in the model or in the satellite observations. Several synthetic tests, during which an artificial error was added to the"true" soil moisture fields, showed that the methodology is able to correct the errors (Jimenez et al., submitted, 2012). This evaluation technique is very general and can be applied to any modelled parameter for which sensitive satellite observations are available. The use of NNs simplifies the evaluation of the model against satellite observations and is particularly well-suited to utilize the synergy from the observations at different wavelengths (Aires et al., 2005, 2012). In this study the proposed methodology has been applied to evaluate SM fields from a number of land surface models against a synergy of satellite observations from passive and active microwave, infrared and visible sensors. In an inter-comparison of the performance of several land surface models (ORCHIDEE (de Rosnay et al., 2002), HTESSEL (Balsamo et al., 2009), JULES (Best et al., 2011) ) it was found that the soil moisture fields from JULES, HTESSEL and ORCHIDEE are very consistent with the observations, but ORCHIDEE soil moisture shows larger local deviations close to some river basins (Kolassa et al., in press, 2012; Jimenez et al., submitted, 2012). Differences between all models and the observations could also be observed in the Eastern US and over mountainous regions, however, the errors here are more likely

Use of Earth Observing Satellites for Operational Hazard Support

NASA Astrophysics Data System (ADS)

Wood, H. M.; Lauritson, L.

The National Oceanic and Atmospheric Administration (NOAA) relies on Earth observing satellite data to carry out its operational mission to monitor, predict, and assess changes in the Earth's atmosphere, land, and oceans. NOAA's National Environmental Satellite, Data, and Information Service (NESDIS) uses satellite data to help lessen the impacts of natural and man-made disasters due to tropical cyclones, flash floods, heavy snowstorms, volcanic ash clouds (for aviation safety), sea ice (for shipping safety), and harmful algal blooms. Communications systems on NOAA satellites are used to support search and rescue and to relay data from data collection platforms to a variety of users. NOAA's Geostationary (GOES) and Polar (POES) Operational Environmental Satellites are used in conjunction with other satellites to support NOAA's operational mission. While NOAA's National Hurricane Center is responsible for predicting tropical cyclones affecting the U.S. mainland, NESDIS continuously monitors the tropics world wide, relaying valuable satellite interpretations of tropical systems strength and position to users throughout the world. Text messages are sent every six hours for tropical cyclones in the Western Pacific, South Pacific, and Indian Oceans. To support the monitoring, prediction, and assessment of flash floods and winter storms, NESDIS sends out text messages alerting U.S. weather forecast offices whenever NOAA satellite imagery indicates the occurrence of heavy rain or snow. NESDIS also produces a 24-hour rainfall composite graphic image covering those areas affected by heavy precipitation. The International Civil Aviation Organization (ICAO) and other aviation concerns recognized the need to keep aviators informed of volcanic hazards. To that end, nine Volcanic Ash Advisory Centers (VAAC's) were created to monitor volcanic ash plumes within their assigned airspace. NESDIS hosts one of the VAAC's. Although the NESDIS VAAC's primary responsibility is the

Operational evapotranspiration based on Earth observation satellites

NASA Astrophysics Data System (ADS)

Gellens-Meulenberghs, Françoise; Ghilain, Nicolas; Arboleda, Alirio; Barrios, Jose-Miguel

2016-04-01

Geostationary satellites have the potential to follow fast evolving atmospheric and Earth surface phenomena such those related to cloud cover evolution and diurnal cycle. Since about 15 years, EUMETSAT has set up a network named 'Satellite Application Facility' (SAF, http://www.eumetsat.int/website/home/Satellites/GroundSegment/Safs/index.html) to complement its ground segment. The Land Surface Analysis (LSA) SAF (http://landsaf.meteo.pt/) is devoted to the development of operational products derived from the European meteorological satellites. In particular, an evapotranspiration (ET) product has been developed by the Royal Meteorological Institute of Belgium. Instantaneous and daily integrated results are produced in near real time and are freely available respectively since the end of 2009 and 2010. The products cover Europe, Africa and the Eastern part of South America with the spatial resolution of the SEVIRI sensor on-board Meteosat Second Generation (MSG) satellites. The ET product algorithm (Ghilain et al., 2011) is based on a simplified Soil-Vegetation-Atmosphere transfer (SVAT) scheme, forced with MSG derived radiative products (LSA SAF short and longwave surface fluxes, albedo). It has been extensively validated against in-situ validation data, mainly FLUXNET observations, demonstrating its good performances except in some arid or semi-arid areas. Research has then been pursued to develop an improved version for those areas. Solutions have been found in reviewing some of the model parameterizations and in assimilating additional satellite products (mainly vegetation indices and land surface temperature) into the model. The ET products will be complemented with related latent and sensible heat fluxes, to allow the monitoring of land surface energy partitioning. The new algorithm version should be tested in the LSA-SAF operational computer system in 2016 and results should become accessible to beta-users/regular users by the end of 2016/early 2017. In

Automated Astrometric Analysis of Satellite Observations using Wide-field Imaging

NASA Astrophysics Data System (ADS)

Skuljan, J.; Kay, J.

2016-09-01

An observational trial was conducted in the South Island of New Zealand from 24 to 28 February 2015, as a collaborative effort between the United Kingdom and New Zealand in the area of space situational awareness. The aim of the trial was to observe a number of satellites in low Earth orbit using wide-field imaging from two separate locations, in order to determine the space trajectory and compare the measurements with the predictions based on the standard two-line elements. This activity was an initial step in building a space situational awareness capability at the Defence Technology Agency of the New Zealand Defence Force. New Zealand has an important strategic position as the last land mass that many satellites selected for deorbiting pass before entering the Earth's atmosphere over the dedicated disposal area in the South Pacific. A preliminary analysis of the trial data has demonstrated that relatively inexpensive equipment can be used to successfully detect satellites at moderate altitudes. A total of 60 satellite passes were observed over the five nights of observation and about 2600 images were collected. A combination of cooled CCD and standard DSLR cameras were used, with a selection of lenses between 17 mm and 50 mm in focal length, covering a relatively wide field of view of 25 to 60 degrees. The CCD cameras were equipped with custom-made GPS modules to record the time of exposure with a high accuracy of one millisecond, or better. Specialised software has been developed for automated astrometric analysis of the trial data. The astrometric solution is obtained as a two-dimensional least-squares polynomial fit to the measured pixel positions of a large number of stars (typically 1000) detected across the image. The star identification is fully automated and works well for all camera-lens combinations used in the trial. A moderate polynomial degree of 3 to 5 is selected to take into account any image distortions introduced by the lens. A typical RMS

POD experiments using real and simulated time-sharing observations for GEO satellites in C-band transfer ranging system

NASA Astrophysics Data System (ADS)

Fen, Cao; XuHai, Yang; ZhiGang, Li; ChuGang, Feng

2016-08-01

The normal consecutive observing model in Chinese Area Positioning System (CAPS) can only supply observations of one GEO satellite in 1 day from one station. However, this can't satisfy the project need for observing many GEO satellites in 1 day. In order to obtain observations of several GEO satellites in 1 day like GPS/GLONASS/Galileo/BeiDou, the time-sharing observing model for GEO satellites in CAPS needs research. The principle of time-sharing observing model is illuminated with subsequent Precise Orbit Determination (POD) experiments using simulated time-sharing observations in 2005 and the real time-sharing observations in 2015. From time-sharing simulation experiments before 2014, the time-sharing observing 6 GEO satellites every 2 h has nearly the same orbit precision with the consecutive observing model. From POD experiments using the real time-sharing observations, POD precision for ZX12# and Yatai7# are about 3.234 m and 2.570 m, respectively, which indicates the time-sharing observing model is appropriate for CBTR system and can realize observing many GEO satellites in 1 day.

Aerosol loading in the Southeastern United States: reconciling surface and satellite observations

NASA Astrophysics Data System (ADS)

Ford, B.; Heald, C. L.

2013-04-01

We investigate the seasonality in aerosols over the Southeastern United States using observations from several satellite instruments (MODIS, MISR, CALIOP) and surface network sites (IMPROVE, SEARCH, AERONET). We find that the strong summertime enhancement in satellite-observed aerosol optical depth (factor 2-3 enhancement over wintertime AOD) is not present in surface mass concentrations (25-55% summertime enhancement). Goldstein et al. (2009) previously attributed this seasonality in AOD to biogenic organic aerosol; however, surface observations show that organic aerosol only accounts for ~35% of PM2.5 mass and exhibits similar seasonality to total PM2.5. The GEOS-Chem model generally reproduces these surface aerosol measurements, but under represents the AOD seasonality observed by satellites. We show that seasonal differences in water uptake cannot sufficiently explain the magnitude of AOD increase. As CALIOP profiles indicate the presence of additional aerosol in the lower troposphere (below 700 hPa), which cannot be explained by vertical mixing; we conclude that the discrepancy is due to a missing source of aerosols above the surface in summer.

Integrating Satellite, Radar and Surface Observation with Time and Space Matching

NASA Astrophysics Data System (ADS)

Ho, Y.; Weber, J.

2015-12-01

The Integrated Data Viewer (IDV) from Unidata is a Java™-based software framework for analyzing and visualizing geoscience data. It brings together the ability to display and work with satellite imagery, gridded data, surface observations, balloon soundings, NWS WSR-88D Level II and Level III RADAR data, and NOAA National Profiler Network data, all within a unified interface. Applying time and space matching on the satellite, radar and surface observation datasets will automatically synchronize the display from different data sources and spatially subset to match the display area in the view window. These features allow the IDV users to effectively integrate these observations and provide 3 dimensional views of the weather system to better understand the underlying dynamics and physics of weather phenomena.

CCD observations of Phoebe, 9th satellite of Saturn

NASA Astrophysics Data System (ADS)

Fienga, A.; Arlot, J.-E.; Baron, N.; Bec-Borsenberger, A.; Crochot, A.; Emelyanov, N.; Thuillot, W.

2002-08-01

In 1998 and 1999, we started observations of the 9th satellite of Saturn. We made 163 observations using the 120 cm-telescope of Observatoire de Haute-Provence, France. We used the USNO A2 catalogue of stars for the astrometric reduction. With the help of observations of optical counterparts of ICRF sources, a zonal correction to the USNO A2.0 catalogue was computed and applied to the Phoebe positions. A comparison with the most recent theories was made.

Effective Utilization of Satellite Observations for Assessing Transnational Impact of Disasters

NASA Astrophysics Data System (ADS)

Alozie, J. E.; Anuforom, A. C.

2014-12-01

General meteorological observations sources for the surface, upper air and outer space are conducted using different technological equipment and instruments that meet international standards prescribed and approved by the United Nations organizations such as the International Civil Aviation Organization (ICAO) and the World Meteorological Organization (WMO). Satellite weather observations are critical for effective monitoring of the developments, propagations and disseminations of cold clouds and their expected adverse weather conditions as they move across national and transnational boundaries. The Nigerian Meteorological Agency (NiMet) which is the national weather service provider for Nigeria, utilizes an array of satellite products obtained from mainly the European Meteorological Satellite (EUMETSAT) for its routine weather and climate monitoring and forecasts. Overtime, NiMet has used weather workstations such as MSG, SYNERGIE and now PUMA for accessing satellite products such as RGB, Infra-red, Water vapour and the Multi-sensor Precipitation Estimate (MPE) obtained at near real-time periods. The satellite imageries find extensive applications in the delivery of early warning of raising of severe weather conditions such as dust storm and dust haze during the harmattan season (November - February); and thunderstorm accompanied by severe lightning and destructive strong winds. The paper will showcase some special cases of the tracking of squall lines and issuance of weather alerts through the media. The good result is that there was limited damage to infrastructure and no loss of life from the flash floods caused by the heavy rainfall from the squally thunderstorm.

Correlation of satellite lightning observations with ground-based lightning experiments in Florida, Texas and Oklahoma

NASA Technical Reports Server (NTRS)

Edgar, B. C.; Turman, B. N.

1982-01-01

Satellite observations of lightning were correlated with ground-based measurements of lightning from data bases obtained at three separate sites. The percentage of ground-based observations of lightning that would be seen by an orbiting satellite was determined.

Current Sounding Capability From Satellite Meteorological Observation With Ultraspectral Infrared Instruments

NASA Technical Reports Server (NTRS)

Zhou, Daniel K.; Liu, Xu; Larar, Allen M.

2008-01-01

Ultraspectral resolution infrared spectral radiance obtained from near nadir observations provide atmospheric, surface, and cloud property information. The intent of the measurement of tropospheric thermodynamic state and trace abundances is the initialization of climate models and the monitoring of air quality. The NPOESS Airborne Sounder Testbed-Interferometer (NAST-I), designed to support the development of future satellite temperature and moisture sounders, aboard high altitude aircraft has been collecting data throughout many field campaigns. An advanced retrieval algorithm developed with NAST-I is now applied to satellite data collected with the Atmospheric InfraRed Sounder (AIRS) on the Aqua satellite launched on 4 May 2002 and the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp satellite launched on October 19, 2006. These instruments possess an ultra-spectral resolution, for example, both IASI and NAST-I have 0.25 cm-1 and a spectral coverage from 645 to 2760 cm-1. The retrieval algorithm with a fast radiative transfer model, including cloud effects, is used for atmospheric profile and cloud parameter retrieval. The physical inversion scheme has been developed, dealing with cloudy as well as cloud-free radiance observed with ultraspectral infrared sounders, to simultaneously retrieve surface, atmospheric thermodynamic, and cloud microphysical parameters. A fast radiative transfer model, which applies to the clouded atmosphere, is used for atmospheric profile and cloud parameter retrieval. A one-dimensional (1-d) variational multi-variable inversion solution is used to improve an iterative background state defined by an eigenvector-regression-retrieval. The solution is iterated in order to account for non-linearity in the 1-d variational solution. It is shown that relatively accurate temperature and moisture retrievals can be achieved below optically thin clouds. For optically thick clouds, accurate temperature and moisture profiles down to

Astrometric observations of Saturn's satellites from McDonald Observatory, 1972. [using reference stars

NASA Technical Reports Server (NTRS)

Abbot, R. I.; Mulholland, J. D.; Shelus, P. J.

1974-01-01

Observations of Saturn's satellites were reduced by means of secondary reference stars obtained by reduction of Palomar Sky Survey (PSS) plates. This involved the use of 39 SAO stars and plate overlap technique to determine the coordinates of 59 fainter stars in the satellite field. Fourteen plate constants were determined for each of the two PSS plates. Comparison of two plate measurement and reduction techniques on the satellite measurements demonstrate the existence of a serious background gradient effect and the utility of microdensitometry to eliminate this error source in positional determinations of close satellites.

Who launched what, when and why; trends in global land-cover observation capacity from civilian earth observation satellites

NASA Astrophysics Data System (ADS)

Belward, Alan S.; Skøien, Jon O.

2015-05-01

This paper presents a compendium of satellites under civilian and/or commercial control with the potential to gather global land-cover observations. From this we show that a growing number of sovereign states are acquiring capacity for space based land-cover observations and show how geopolitical patterns of ownership are changing. We discuss how the number of satellites flying at any time has progressed as a function of increased launch rates and mission longevity, and how the spatial resolutions of the data they collect has evolved. The first such satellite was launched by the USA in 1972. Since then government and/or private entities in 33 other sovereign states and geopolitical groups have chosen to finance such missions and 197 individual satellites with a global land-cover observing capacity have been successfully launched. Of these 98 were still operating at the end of 2013. Since the 1970s the number of such missions failing within 3 years of launch has dropped from around 60% to less than 20%, the average operational life of a mission has almost tripled, increasing from 3.3 years in the 1970s to 8.6 years (and still lengthening), the average number of satellites launched per-year/per-decade has increased from 2 to 12 and spatial resolution increased from around 80 m to less than 1 m multispectral and less than half a meter for panchromatic; synthetic aperture radar resolution has also fallen, from 25 m in the 1970s to 1 m post 2007. More people in more countries have access to data from global land-cover observing spaceborne missions at a greater range of spatial resolutions than ever before. We provide a compendium of such missions, analyze the changes and shows how innovation, the need for secure data-supply, national pride, falling costs and technological advances may underpin the trends we document.

Advancing land surface model development with satellite-based Earth observations

NASA Astrophysics Data System (ADS)

Orth, Rene; Dutra, Emanuel; Trigo, Isabel F.; Balsamo, Gianpaolo

2017-04-01

The land surface forms an essential part of the climate system. It interacts with the atmosphere through the exchange of water and energy and hence influences weather and climate, as well as their predictability. Correspondingly, the land surface model (LSM) is an essential part of any weather forecasting system. LSMs rely on partly poorly constrained parameters, due to sparse land surface observations. With the use of newly available land surface temperature observations, we show in this study that novel satellite-derived datasets help to improve LSM configuration, and hence can contribute to improved weather predictability. We use the Hydrology Tiled ECMWF Scheme of Surface Exchanges over Land (HTESSEL) and validate it comprehensively against an array of Earth observation reference datasets, including the new land surface temperature product. This reveals satisfactory model performance in terms of hydrology, but poor performance in terms of land surface temperature. This is due to inconsistencies of process representations in the model as identified from an analysis of perturbed parameter simulations. We show that HTESSEL can be more robustly calibrated with multiple instead of single reference datasets as this mitigates the impact of the structural inconsistencies. Finally, performing coupled global weather forecasts we find that a more robust calibration of HTESSEL also contributes to improved weather forecast skills. In summary, new satellite-based Earth observations are shown to enhance the multi-dataset calibration of LSMs, thereby improving the representation of insufficiently captured processes, advancing weather predictability and understanding of climate system feedbacks. Orth, R., E. Dutra, I. F. Trigo, and G. Balsamo (2016): Advancing land surface model development with satellite-based Earth observations. Hydrol. Earth Syst. Sci. Discuss., doi:10.5194/hess-2016-628

Chemistry-Transport Modeling of the Satellite Observed Distribution of Tropical Tropospheric Ozone

NASA Technical Reports Server (NTRS)

Peters, Wouter; Krol, Maarten; Dentener, Frank; Thompson, Anne M.; Leloeveld, Jos; Bhartia, P. K. (Technical Monitor)

2002-01-01

We have compared the 14-year record of satellite derived tropical tropospheric ozone columns (TTOC) from the NIMBUS-7 Total Ozone Mapping Spectrometer (TOMS) to TTOC calculated by a chemistry-transport model (CTM). An objective measure of error, based on the zonal distribution of TTOC in the tropics, is applied to perform this comparison systematically. In addition, the sensitivity of the model to several key processes in the tropics is quantified to select directions for future improvements. The comparisons indicate a widespread, systematic (20%) discrepancy over the tropical Atlantic Ocean, which maximizes during austral Spring. Although independent evidence from ozonesondes shows that some of the disagreement is due to satellite over-estimate of TTOC, the Atlantic mismatch is largely due to a misrepresentation of seasonally recurring processes in the model. Only minor differences between the model and observations over the Pacific occur, mostly due to interannual variability not captured by the model. Although chemical processes determine the TTOC extent, dynamical processes dominate the TTOC distribution, as the use of actual meteorology pertaining to the year of observations always leads to a better agreement with TTOC observations than using a random year or a climatology. The modeled TTOC is remarkably insensitive to many model parameters due to efficient feedbacks in the ozone budget. Nevertheless, the simulations would profit from an improved biomass burning calendar, as well as from an increase in NOX abundances in free tropospheric biomass burning plumes. The model showed the largest response to lightning NOX emissions, but systematic improvements could not be found. The use of multi-year satellite derived tropospheric data to systematically test and improve a CTM is a promising new addition to existing methods of model validation, and is a first step to integrating tropospheric satellite observations into global ozone modeling studies. Conversely

NASDA's earth observation satellite data archive policy for the earth observation data and information system (EOIS)

NASA Technical Reports Server (NTRS)

Sobue, Shin-ichi; Yoshida, Fumiyoshi; Ochiai, Osamu

1996-01-01

NASDA's new Advanced Earth Observing Satellite (ADEOS) is scheduled for launch in August, 1996. ADEOS carries 8 sensors to observe earth environmental phenomena and sends their data to NASDA, NASA, and other foreign ground stations around the world. The downlink data bit rate for ADEOS is 126 MB/s and the total volume of data is about 100 GB per day. To archive and manage such a large quantity of data with high reliability and easy accessibility it was necessary to develop a new mass storage system with a catalogue information database using advanced database management technology. The data will be archived and maintained in the Master Data Storage Subsystem (MDSS) which is one subsystem in NASDA's new Earth Observation data and Information System (EOIS). The MDSS is based on a SONY ID1 digital tape robotics system. This paper provides an overview of the EOIS system, with a focus on the Master Data Storage Subsystem and the NASDA Earth Observation Center (EOC) archive policy for earth observation satellite data.

Geometric Positioning for Satellite Imagery without Ground Control Points by Exploiting Repeated Observation.

PubMed

Ma, Zhenling; Wu, Xiaoliang; Yan, Li; Xu, Zhenliang

2017-01-26

With the development of space technology and the performance of remote sensors, high-resolution satellites are continuously launched by countries around the world. Due to high efficiency, large coverage and not being limited by the spatial regulation, satellite imagery becomes one of the important means to acquire geospatial information. This paper explores geometric processing using satellite imagery without ground control points (GCPs). The outcome of spatial triangulation is introduced for geo-positioning as repeated observation. Results from combining block adjustment with non-oriented new images indicate the feasibility of geometric positioning with the repeated observation. GCPs are a must when high accuracy is demanded in conventional block adjustment; the accuracy of direct georeferencing with repeated observation without GCPs is superior to conventional forward intersection and even approximate to conventional block adjustment with GCPs. The conclusion is drawn that taking the existing oriented imagery as repeated observation enhances the effective utilization of previous spatial triangulation achievement, which makes the breakthrough for repeated observation to improve accuracy by increasing the base-height ratio and redundant observation. Georeferencing tests using data from multiple sensors and platforms with the repeated observation will be carried out in the follow-up research.

Constraining Earth System Models in the Tropics with Multiple Satellite Observations

NASA Astrophysics Data System (ADS)

Shi, M.; Liu, J.; Saatchi, S. S.; Chan, S.; Yu, Y.; Zhao, M.

2016-12-01

Because of the impacts of cloud and atmospheric aerosol on spectral observations and the saturation of spectral observations over dense forests, the current spectral observations (e.g., Moderate Resolution Imaging Spectroradiometer) have large uncertainties in the tropics. Nevertheless, the backscatter observations from the SeaWinds Scatterometer onboard QuikSCAT (QSCAT) are sensitive to the variations of canopy water content and structure of forest canopy, and are not affected by clouds and atmospheric aerosols. In addition, the lack of sensitivity of the Soil Moisture Active Passive (SMAP) Level 1C brightness temperature (TB) to soil moisture under dense forest canopies (e.g., forests in tropics) makes the SMAP TB data a direct indicator of canopy properties. In this study, we use a variety of new satellite observations, including the QSCAT backscatter observations, the Gravity Recovery and Climate Experiment (GRACE) satellite's observed temporal gravity field variations, and the SMAP Level 1C TB, to constrain the carbon (C) cycle simulated by the Community Land Model version 4.5 BGC (CLM4.5) for the 2005 Amazonia drought and 2015 El Nino. Our results show that the leaf C pool size simulated by CLM4.5 decreases dramatically in southwest Amazonia in the 2005 drought, and recovers slowly afterward (after about 3 years). This result is consistent with the long-term C-recovery after the 2005 Amazonia drought observed by QSCAT. The slow C pool recovery is associated with large fire disturbance and the slow water storage recovery simulated by CLM4.5 and observed by GRACE. We will also discuss the impact of the 2015 El Nino on the tropical C dynamics constrained by SMAP Level 1C data. This study represents an innovative way of using satellite microwave observations to constrain C cycle in an Earth system model.

Retrieving Temperature Anomaly in the Global Subsurface and Deeper Ocean From Satellite Observations

NASA Astrophysics Data System (ADS)

Su, Hua; Li, Wene; Yan, Xiao-Hai

2018-01-01

Retrieving the subsurface and deeper ocean (SDO) dynamic parameters from satellite observations is crucial for effectively understanding ocean interior anomalies and dynamic processes, but it is challenging to accurately estimate the subsurface thermal structure over the global scale from sea surface parameters. This study proposes a new approach based on Random Forest (RF) machine learning to retrieve subsurface temperature anomaly (STA) in the global ocean from multisource satellite observations including sea surface height anomaly (SSHA), sea surface temperature anomaly (SSTA), sea surface salinity anomaly (SSSA), and sea surface wind anomaly (SSWA) via in situ Argo data for RF training and testing. RF machine-learning approach can accurately retrieve the STA in the global ocean from satellite observations of sea surface parameters (SSHA, SSTA, SSSA, SSWA). The Argo STA data were used to validate the accuracy and reliability of the results from the RF model. The results indicated that SSHA, SSTA, SSSA, and SSWA together are useful parameters for detecting SDO thermal information and obtaining accurate STA estimations. The proposed method also outperformed support vector regression (SVR) in global STA estimation. It will be a useful technique for studying SDO thermal variability and its role in global climate system from global-scale satellite observations.

Fast Emission Estimates in China Constrained by Satellite Observations (Invited)

NASA Astrophysics Data System (ADS)

Mijling, B.; van der A, R.

2013-12-01

Emission inventories of air pollutants are crucial information for policy makers and form important input data for air quality models. Unfortunately, bottom-up emission inventories, compiled from large quantities of statistical data, are easily outdated for an emerging economy such as China, where rapid economic growth changes emissions accordingly. Alternatively, top-down emission estimates from satellite observations of air constituents have important advantages of being spatial consistent, having high temporal resolution, and enabling emission updates shortly after the satellite data become available. Constraining emissions from concentration measurements is, however, computationally challenging. Within the GlobEmission project of the European Space Agency (ESA) a new algorithm has been developed, specifically designed for fast daily emission estimates of short-lived atmospheric species on a mesoscopic scale (0.25 × 0.25 degree) from satellite observations of column concentrations. The algorithm needs only one forward model run from a chemical transport model to calculate the sensitivity of concentration to emission, using trajectory analysis to account for transport away from the source. By using a Kalman filter in the inverse step, optimal use of the a priori knowledge and the newly observed data is made. We apply the algorithm for NOx emission estimates in East China, using the CHIMERE model together with tropospheric NO2 column retrievals of the OMI and GOME-2 satellite instruments. The observations are used to construct a monthly emission time series, which reveal important emission trends such as the emission reduction measures during the Beijing Olympic Games, and the impact and recovery from the global economic crisis. The algorithm is also able to detect emerging sources (e.g. new power plants) and improve emission information for areas where proxy data are not or badly known (e.g. shipping emissions). The new emission estimates result in a better

Use of Multiangle Satellite Observations to Retrieve Aerosol Properties and Ocean Color

NASA Technical Reports Server (NTRS)

Martonchik, John V.; Diner, David; Khan, Ralph

2005-01-01

A new technique is described for retrieving aerosol over ocean water and the associated ocean color using multiangle satellite observations. Unlike current satellite aerosol retrieval algorithms which only utilize observations at red wavelengths and longer, with the assumption that these wavelengths have a negligible ocean (water-leaving radiance), this new algorithm uses all available spectral bands and simultaneously retrieves both aerosol properties and the spectral ocean color. We show some results of case studies using MISR data, performed over different water conditions (coastal water, blooms, and open water).

Neural Networks Technique for Filling Gaps in Satellite Measurements: Application to Ocean Color Observations.

PubMed

Krasnopolsky, Vladimir; Nadiga, Sudhir; Mehra, Avichal; Bayler, Eric; Behringer, David

2016-01-01

A neural network (NN) technique to fill gaps in satellite data is introduced, linking satellite-derived fields of interest with other satellites and in situ physical observations. Satellite-derived "ocean color" (OC) data are used in this study because OC variability is primarily driven by biological processes related and correlated in complex, nonlinear relationships with the physical processes of the upper ocean. Specifically, ocean color chlorophyll-a fields from NOAA's operational Visible Imaging Infrared Radiometer Suite (VIIRS) are used, as well as NOAA and NASA ocean surface and upper-ocean observations employed--signatures of upper-ocean dynamics. An NN transfer function is trained, using global data for two years (2012 and 2013), and tested on independent data for 2014. To reduce the impact of noise in the data and to calculate a stable NN Jacobian for sensitivity studies, an ensemble of NNs with different weights is constructed and compared with a single NN. The impact of the NN training period on the NN's generalization ability is evaluated. The NN technique provides an accurate and computationally cheap method for filling in gaps in satellite ocean color observation fields and time series.

Neural Networks Technique for Filling Gaps in Satellite Measurements: Application to Ocean Color Observations

PubMed Central

Nadiga, Sudhir; Mehra, Avichal; Bayler, Eric; Behringer, David

2016-01-01

A neural network (NN) technique to fill gaps in satellite data is introduced, linking satellite-derived fields of interest with other satellites and in situ physical observations. Satellite-derived “ocean color” (OC) data are used in this study because OC variability is primarily driven by biological processes related and correlated in complex, nonlinear relationships with the physical processes of the upper ocean. Specifically, ocean color chlorophyll-a fields from NOAA's operational Visible Imaging Infrared Radiometer Suite (VIIRS) are used, as well as NOAA and NASA ocean surface and upper-ocean observations employed—signatures of upper-ocean dynamics. An NN transfer function is trained, using global data for two years (2012 and 2013), and tested on independent data for 2014. To reduce the impact of noise in the data and to calculate a stable NN Jacobian for sensitivity studies, an ensemble of NNs with different weights is constructed and compared with a single NN. The impact of the NN training period on the NN's generalization ability is evaluated. The NN technique provides an accurate and computationally cheap method for filling in gaps in satellite ocean color observation fields and time series. PMID:26819586

Atronomical CCD observations of the main Saturn's satellites at Pulkovo Observatory in 2004-2007

NASA Astrophysics Data System (ADS)

Khrutskaya, E. V.; Kiseleva, T. P.; Izmailov, I. S.; Khovrichev, M. Yu.; Berezhnoy, A. A.

2009-08-01

The results of astrometric observations of Saturn’s satellites (S1-S8) obtained using a 26-inch refractor and a normal astrograph at Pulkovo Observatory in 2004-2007 are given. High-accuracy equatorial coordinates of Saturn’s satellites in the system of the UCAC2 reference catalog and the relative “satellite-satellite” positions suitable for specifying their motion theories are obtained. The observations are compared with the DE405 + TASS1.7 and INPOP06 + TASS1.7 theories of motion. The root-mean-square errors of the obtained satellite positions lie within the range of 10-50 mas, as far as the intrinsic convergence is concerned, and 20-70 mas, as far as the extrinsic one is concerned. The observation results are included into the astrometrical database of the Pulkovo Observatory ( www.puldb.ru ).

Aerosol loading in the Southeastern United States: reconciling surface and satellite observations

NASA Astrophysics Data System (ADS)

Ford, B.; Heald, C. L.

2013-09-01

We investigate the seasonality in aerosols over the Southeastern United States using observations from several satellite instruments (MODIS, MISR, CALIOP) and surface network sites (IMPROVE, SEARCH, AERONET). We find that the strong summertime enhancement in satellite-observed aerosol optical depth (AOD) (factor 2-3 enhancement over wintertime AOD) is not present in surface mass concentrations (25-55% summertime enhancement). Goldstein et al. (2009) previously attributed this seasonality in AOD to biogenic organic aerosol; however, surface observations show that organic aerosol only accounts for ∼35% of fine particulate matter (smaller than 2.5 μm in aerodynamic diameter, PM2.5) and exhibits similar seasonality to total surface PM2.5. The GEOS-Chem model generally reproduces these surface aerosol measurements, but underrepresents the AOD seasonality observed by satellites. We show that seasonal differences in water uptake cannot sufficiently explain the magnitude of AOD increase. As CALIOP profiles indicate the presence of additional aerosol in the lower troposphere (below 700 hPa), which cannot be explained by vertical mixing, we conclude that the discrepancy is due to a missing source of aerosols above the surface layer in summer.

Cassini VIMS observations of the Galilean satellites including the VIMS calibration procedure

USGS Publications Warehouse

McCord, T.B.; Coradini, A.; Hibbitts, C.A.; Capaccioni, F.; Hansen, G.B.; Filacchione, G.; Clark, R.N.; Cerroni, P.; Brown, R.H.; Baines, K.H.; Bellucci, G.; Bibring, J.-P.; Buratti, B.J.; Bussoletti, E.; Combes, M.; Cruikshank, D.P.; Drossart, P.; Formisano, V.; Jaumann, R.; Langevin, Y.; Matson, D.L.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe

2004-01-01

The Visual and Infrared Mapping Spectrometer (VIMS) observed the Galilean satellites during the Cassini spacecraft's 2000/2001 flyby of Jupiter, providing compositional and thermal information about their surfaces. The Cassini spacecraft approached the jovian system no closer than about 126 Jupiter radii, about 9 million kilometers, at a phase angle of < 90 ??, resulting in only sub-pixel observations by VIMS of the Galilean satellites. Nevertheless, most of the spectral features discovered by the Near Infrared Mapping Spectrometer (NIMS) aboard the Galileo spacecraft during more than four years of observations have been identified in the VIMS data analyzed so far, including a possible 13C absorption. In addition, VIMS made observations in the visible part of the spectrum and at several new phase angles for all the Galilean satellites and the calculated phase functions are presented. In the process of analyzing these data, the VIMS radiometric and spectral calibrations were better determined in preparation for entry into the Saturn system. Treatment of these data is presented as an example of the VIMS data reduction, calibration and analysis process and a detailed explanation is given of the calibration process applied to the Jupiter data. ?? 2004 Elsevier Inc. All rights reserved.

Review: advances in in situ and satellite phenological observations in Japan

NASA Astrophysics Data System (ADS)

Nagai, Shin; Nasahara, Kenlo Nishida; Inoue, Tomoharu; Saitoh, Taku M.; Suzuki, Rikie

2016-04-01

To accurately evaluate the responses of spatial and temporal variation of ecosystem functioning (evapotranspiration and photosynthesis) and services (regulating and cultural services) to the rapid changes caused by global warming, we depend on long-term, continuous, near-surface, and satellite remote sensing of phenology over wide areas. Here, we review such phenological studies in Japan and discuss our current knowledge, problems, and future developments. In contrast with North America and Europe, Japan has been able to evaluate plant phenology along vertical and horizontal gradients within a narrow area because of the country's high topographic relief. Phenological observation networks that support scientific studies and outreach activities have used near-surface tools such as digital cameras and spectral radiometers. Differences in phenology among ecosystems and tree species have been detected by analyzing the seasonal variation of red, green, and blue digital numbers (RGB values) extracted from phenological images, as well as spectral reflectance and vegetation indices. The relationships between seasonal variations in RGB-derived indices or spectral characteristics and the ecological and CO2 flux measurement data have been well validated. In contrast, insufficient satellite remote-sensing observations have been conducted because of the coarse spatial resolution of previous datasets, which could not detect the heterogeneous plant phenology that results from Japan's complex topography and vegetation. To improve Japanese phenological observations, multidisciplinary analysis and evaluation will be needed to link traditional phenological observations with "index trees," near-surface and satellite remote-sensing observations, "citizen science" (observations by citizens), and results published on the Internet.

Surface Soil Moisture Estimates Across China Based on Multi-satellite Observations and A Soil Moisture Model

NASA Astrophysics Data System (ADS)

Zhang, Ke; Yang, Tao; Ye, Jinyin; Li, Zhijia; Yu, Zhongbo

2017-04-01

Soil moisture is a key variable that regulates exchanges of water and energy between land surface and atmosphere. Soil moisture retrievals based on microwave satellite remote sensing have made it possible to estimate global surface (up to about 10 cm in depth) soil moisture routinely. Although there are many satellites operating, including NASA's Soil Moisture Acitive Passive mission (SMAP), ESA's Soil Moisture and Ocean Salinity mission (SMOS), JAXA's Advanced Microwave Scanning Radiometer 2 mission (AMSR2), and China's Fengyun (FY) missions, key differences exist between different satellite-based soil moisture products. In this study, we applied a single-channel soil moisture retrieval model forced by multiple sources of satellite brightness temperature observations to estimate consistent daily surface soil moisture across China at a spatial resolution of 25 km. By utilizing observations from multiple satellites, we are able to estimate daily soil moisture across the whole domain of China. We further developed a daily soil moisture accounting model and applied it to downscale the 25-km satellite-based soil moisture to 5 km. By comparing our estimated soil moisture with observations from a dense observation network implemented in Anhui Province, China, our estimated soil moisture results show a reasonably good agreement with the observations (RMSE < 0.1 and r > 0.8).

The artificial satellite observation chronograph controlled by single chip microcomputer.

NASA Astrophysics Data System (ADS)

Pan, Guangrong; Tan, Jufan; Ding, Yuanjun

1991-06-01

The instrument specifications, hardware structure, software design, and other characteristics of the chronograph mounting on a theodolite used for artificial satellite observation are presented. The instrument is a real time control system with a single chip microcomputer.

Severe storms observing satellite (STORMSAT)

NASA Technical Reports Server (NTRS)

1976-01-01

The primary payload for this satellite is the Advanced Atmospheric Sounding and Imaging Radiometer which will perform precise infrared temperature sounding and visible/infrared imaging from geostationary orbit. A secondary payload instrument which may be utilized on STORMSAT is the Microwave Atmospheric Sounding Radiometer which provides an independent set of temperature and humidity sounding in cloudy, meteorologically active regions. The study provides satellite designs and identifies mission-unique subsystems using the Multimission Modular Spacecraft using a Shuttle/Interim Upper Stage launch vehicle.

First validation of satellite microwave liquid water path with ship-based observations in marine low clouds

NASA Astrophysics Data System (ADS)

Painemal, D.; Cadeddu, M. P.; Greenwald, T. J.; Minnis, P.

2015-12-01

We present the first validation study of satellite microwave liquid water path, from four operational sensors, against in-situ observations from a ship-borne three-channel microwave radiometer collected over the northeast Pacific during May-August of 2013, along a ship transect length of 40˚ (33.7˚N, 118.2˚W - 21.3˚N, 157.8˚W). The satellite sensors analyzed here are: The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), Special Sensor Microwave Imager/Sounder (SSMIS) on the Defense Meteorological Satellite Program F16 and F17 satellites, and The Advanced Microwave Scanning Radiometer (AMSR-2) on board the Global Change Observation Mission - Water (GCOM-W1). Satellite retrievals show an overall correlation with hourly-averaged in-situ observations of 0.86 and a positive bias of 10.0 gm2, which decreases to 1.0 gm2 and a correlation that increases to 0.91 when selecting overcast scenes. The satellite bias for broken scenes remains below 22.2 gm2, although the removal of clear-sky in-situ samples yields an unbiased relationship. Satellites produce a diurnal cycle with amplitudes (35-47 gm2) consistent with ship-based observations. Longitudinal biases remain below 17.4 gm2, and they are negligible in overcast scenes and when clear-sky samples are removed from the in-situ hourly average. Our study indicates that satellite microwave retrievals are a reliable dataset for climate studies in marine warm low clouds. The implications for satellite visible/infrared retrievals will be also discussed.

Classification of Clouds and Deep Convection from GEOS-5 Using Satellite Observations

NASA Technical Reports Server (NTRS)

Putman, William; Suarez, Max

2010-01-01

With the increased resolution of global atmospheric models and the push toward global cloud resolving models, the resemblance of model output to satellite observations has become strikingly similar. As we progress with our adaptation of the Goddard Earth Observing System Model, Version 5 (GEOS-5) as a high resolution cloud system resolving model, evaluation of cloud properties and deep convection require in-depth analysis beyond a visual comparison. Outgoing long-wave radiation (OLR) provides a sufficient comparison with infrared (IR) satellite imagery to isolate areas of deep convection. We have adopted a binning technique to generate a series of histograms for OLR which classify the presence and fraction of clear sky versus deep convection in the tropics that can be compared with a similar analyses of IR imagery from composite Geostationary Operational Environmental Satellite (GOES) observations. We will present initial results that have been used to evaluate the amount of deep convective parameterization required within the model as we move toward cloud system resolving resolutions of 10- to 1-km globally.

Data Fusion for Earth Science Remote Sensing

NASA Technical Reports Server (NTRS)

Braverman, Amy

2007-01-01

Beginning in 2004, NASA has supported the development of an international network of ground-based remote sensing installations for the measurement of greenhouse gas columns. This collaboration has been successful and is currently used in both carbon cycle investigations and in the efforts to validate the GOSAT space-based column observations of CO2 and CH4. With the support of a grant, this research group has established a network of ground-based column observations that provide an essential link between the satellite observations of CO2, CO, and CH4 and the extensive global in situ surface network. The Total Carbon Column Observing Network (TCCON) was established in 2004. At the time of this report seven sites, employing modern instrumentation, were operational or were expected to be shortly. TCCON is expected to expand. In addition to providing the most direct means of tying the in situ and remote sensing data sets together, TCCON provides a means of testing the retrieval algorithms of SCIAMACHY and GOSAT over the broadest variation in atmospheric state. TCCON provides a critically maintained and long timescale record for identification of temporal drift and spatial bias in the calibration of the space-based sensors. Finally, the global observations from TCCON are improving our understanding of how to use column observations to provide robust estimates of surface exchange of C02 and CH4 in advance of the launch of OCO and GOSAT. TCCON data are being used to better understand the impact of both regional fluxes and long-range transport on gradients in the C02 column. Such knowledge is essential for identifying the tools required to best use the space-based observations. The technical approach and methodology of retrieving greenhouse gas columns from near-IR solar spectra, data quality and process control are described. Additionally, the impact of and relevance to NASA of TCCON and satellite validation and carbon science are addressed.

Improving a Spectral Bin Microphysical Scheme Using TRMM Satellite Observations

NASA Technical Reports Server (NTRS)

Li, Xiaowen; Tao, Wei-Kuo; Matsui, Toshihisa; Liu, Chuntao; Masunaga, Hirohiko

2010-01-01

Comparisons between cloud model simulations and observations are crucial in validating model performance and improving physical processes represented in the mod Tel.hese modeled physical processes are idealized representations and almost always have large rooms for improvements. In this study, we use data from two different sensors onboard TRMM (Tropical Rainfall Measurement Mission) satellite to improve the microphysical scheme in the Goddard Cumulus Ensemble (GCE) model. TRMM observed mature-stage squall lines during late spring, early summer in central US over a 9-year period are compiled and compared with a case simulation by GCE model. A unique aspect of the GCE model is that it has a state-of-the-art spectral bin microphysical scheme, which uses 33 different bins to represent particle size distribution of each of the seven hydrometeor species. A forward radiative transfer model calculates TRMM Precipitation Radar (PR) reflectivity and TRMM Microwave Imager (TMI) 85 GHz brightness temperatures from simulated particle size distributions. Comparisons between model outputs and observations reveal that the model overestimates sizes of snow/aggregates in the stratiform region of the squall line. After adjusting temperature-dependent collection coefficients among ice-phase particles, PR comparisons become good while TMI comparisons worsen. Further investigations show that the partitioning between graupel (a high-density form of aggregate), and snow (a low-density form of aggregate) needs to be adjusted in order to have good comparisons in both PR reflectivity and TMI brightness temperature. This study shows that long-term satellite observations, especially those with multiple sensors, can be very useful in constraining model microphysics. It is also the first study in validating and improving a sophisticated spectral bin microphysical scheme according to long-term satellite observations.

Summertime upper tropospheric nitrous oxide over the Mediterranean as a footprint of Asian emissions

NASA Astrophysics Data System (ADS)

Kangah, Yannick; Ricaud, Philippe; Attié, Jean-Luc; Saitoh, Naoko; Hauglustaine, Didier A.; Wang, Rong; El Amraoui, Laaziz; Zbinden, Régina; Delon, Claire

2017-04-01

The aim of this paper is to study the transport of nitrous oxide (N2O) from the Asian surface to the eastern Mediterranean Basin (MB). We used measurements from the spectrometer Thermal and Near infrared Sensor for carbon Observation Fourier transform spectrometer on board the Greenhouse gases Observing SATellite (GOSAT) over the period of 2010-2013. We also used the outputs from the chemical transport model LMDz-OR-INCA over the same period. By comparing GOSAT upper tropospheric retrievals to aircraft measurements from the High-performance Instrumented Airborne Platform for Environmental Research Pole-to-Pole Observations, we calculated a GOSAT High-performance Instrumented Airborne Platform for Environmental Research standard deviation (SD error) of 2.0 ppbv for a single pixel and a mean bias of approximately -1.3 ppbv (approximately -0.4%). This SD error is reduced to 0.1 ppbv when we average the pixels regionally and monthly over the MB. The use of nitrogen fertilizer coupled with high soil humidity during the summer Asian monsoon produces high N2O emissions, which are transported from Asian surfaces to the eastern MB. This summertime enrichment over the eastern MB produces a maximum in the difference between the eastern and the western MB upper tropospheric N2O (east-west difference) in July in both the measurements and the model. N2O over the eastern MB can therefore be considered as a footprint of Asian summertime emissions. However, the peak-to-peak amplitude of the east-west difference observed by GOSAT ( 1.4 ± 0.3 ppbv) is larger than that calculated by LMDz-OR-INCA ( 0.8 ppbv). This is due to an underestimation of N2O emissions in the model and to a relatively coarse spatial resolution of the model that tends to underestimate the N2O accumulation into the Asian monsoon anticyclone.

Satellite Observations of Tropospheric Chemistry

NASA Technical Reports Server (NTRS)

Singh, Hanwant B.; Jacob, Daniel J.; Hipskind, R. Stephen (Technical Monitor)

2001-01-01

The troposphere is an essential component of the earth's life support system as well as the gateway for the exchange of chemicals between different geochemical reservoirs of the earth. The chemistry of the troposphere is sensitive to perturbation from a wide range of natural phenomena and human activities. The societal concern has been greatly enhanced in recent decades due to ever increasing pressures of population growth and industrialization. Chemical changes within the troposphere control a vast array of processes that impact human health, the biosphere, and climate. A main goal of tropospheric chemistry research is to measure and understand the response of atmospheric composition to natural and anthropogenic perturbations, and to develop the capability to predict future change. Atmospheric chemistry measurements are extremely challenging due to the low concentrations of critical species and the vast scales over which the observations must be made. Available tropospheric data are mainly from surface sites and aircraft missions. Because of the limited temporal extent of aircraft observations, we have very limited information on tropospheric composition above the surface. This situation can be contrasted to the stratosphere, where satellites have provided critical and detailed chemical data on the global distribution of key trace gases.

Cassini radar and radiometry observations of Saturn's airless icy satellites

NASA Astrophysics Data System (ADS)

Le Gall, A. A.; West, R.; Janssen, M. A.; Leyrat, C.; Bonnefoy, L.; Lellouch, E.

2017-12-01

The Cassini Radar is a multimode microwave sensor operating in the Ku-band, at a wavelength of 2.2 cm. While it was initially designed to examine the surface of Titan through the veil of its optically-opaque atmosphere, it is occasionally used to observe airless Saturn's moons from long ranges (>50 000 km) and, less frequently, during targeted flybys. In its active mode, the instrument measures the surface reflectivity in the backscattering direction. In its passive mode - or radiometry mode - it records the microwave thermal emission from the near-surface (typically few meters). Doing so, it provides insights into the degree of purity and maturity of the water-ice regolith of the investigated objects. In particular, it can reveal hemispheric dichotomies or regional anomalies and satellite-to-satellite variabilities which give clues into what is common and what is specific to the history of each satellite and to the processes that have shaped their surface/subsurface. In this paper, we will give an overview of the Cassini radar/radiometry observations of Saturnian icy moons, most of which have not been published yet. Now that the mission has come to an end, we will describe how the radio investigation of these objects can be pursued from Earth-based radiotelescopes.

Detecting Patterns of Changing Carbon Uptake in Alaska Using Sustained In Situ and Remote Sensing CO2 Observations

NASA Astrophysics Data System (ADS)

Parazoo, N.; Miller, C. E.; Commane, R.; Wofsy, S. C.; Koven, C.; Lawrence, D. M.; Lindaas, J.; Chang, R. Y. W.; Sweeney, C.

2015-12-01

The future trajectory of Arctic ecosystems as a carbon sink or source is of global importance due to vast quantities of carbon in permafrost soils. Over the last few years, a sustained set of airborne (NOAA-PFA, NOAA-ACG, and CARVE) and satellite (OCO-2 and GOSAT) atmospheric CO2 mole fraction measurements have provided unprecedented space and time scale sampling density across Alaska, making it possible to study the Arctic carbon cycle in more detail than ever before. Here, we use a synthesis of airborne and satellite CO2 over the 2009-2013 period with simulated concentrations from CLM4.5 and GEOS-Chem to examine the extent to which regional-scale carbon cycle changes in Alaska can be distinguished from interannual variability and long-range transport. We show that observational strategies focused on sustained profile measurements spanning continental interiors provide key insights into magnitude, duration, and variability of Summer sink activity, but that cold season sources are currently poorly resolved due to lack of sustained spatial sampling. Consequently, although future CO2 budgets dominated by enhanced cold season emission sources under climate warming and permafrost thaw scenarios are likely to produce substantial changes to near-surface CO2 gradients and seasonal cycle amplitude, they are unlikely to be detected by current observational strategies. We conclude that airborne and ground-based networks that provide more spatial coverage in year round profiles will help compensate for systematic sampling gaps in NIR passive satellite systems and provide essential constraints for Arctic carbon cycle changes.

CORRECTING PHOTOLYSIS RATES ON THE BASIS OF SATELLITE OBSERVED CLOUDS

EPA Science Inventory

Clouds can significantly affect photochemical activities in the boundary layer by altering radiation intensity, and therefore their correct specification in the air quality models is of outmost importance. In this study we introduce a technique for using the satellite observed c...

How well do satellite observations and models capture diurnal variation in aerosols over the Korean Peninsula?

NASA Astrophysics Data System (ADS)

Hyer, E. J.; Xian, P.; Campbell, J. R.

2016-12-01

Aerosol sources, sinks, and transport processes have important variations over the diurnal cycle. Advances in geostationary satellite observation have made it possible to retrieve aerosol properties over a larger fraction of the diurnal cycle in many areas. However, the conditions for retrieval of aerosol from space also have systematic diurnal variation, which must be considered when interpreting satellite data. We used surface PM2.5 observations from the Korean National Institute for Environmental Research, together with the dense network of AERONET sun photometers deployed in Korea for the KORUS-AQ mission in spring 2016, to examine diurnal variations in aerosol conditions and quantify the effect of systematic diurnal processes on daily integrated aerosol quantities of forcing and PM2.5 24-hour exposure. Time-resolved observations of aerosols from in situ data were compared to polar and geostationary satellite observations to evaluate these questions: 1) How well is diurnal variation observed in situ captured by satellite products? 2) Do the satellite products show evidence of systematic biases related to diurnally varying observing conditions? 3) What is the implication of diurnal variation for aerosol forcing estimates based on observations near solar noon? The diurnal variation diagnosed from observations was also compared to the output of the Navy Aerosol Analysis and Prediction System (NAAPS), to examine the ability of this model to capture aerosol diurnal variation. Finally, we discuss the implications of the observed diurnal variation for assimilation of aerosol observations into forecast models.

Compact SAR and Small Satellite Solutions for Earth Observation

NASA Astrophysics Data System (ADS)

LaRosa, M.; L'Abbate, M.

2016-12-01

Requirements for near and short term mission applications (Observation and Reconnaissance, SIGINT, Early Warning, Meteorology,..) are increasingly calling for spacecraft operational responsiveness, flexible configuration, lower cost satellite constellations and flying formations, to improve both the temporal performance of observation systems (revisit, response time) and the remote sensing techniques (distributed sensors, arrays, cooperative sensors). In answer to these users' needs, leading actors in Space Systems for EO are involved in development of Small and Microsatellites solutions. Thales Alenia Space (TAS) has started the "COMPACT-SAR" project to develop a SAR satellite characterized by low cost and reduced mass while providing, at the same time, high image quality in terms of resolution, swath size, and radiometric performance. Compact SAR will embark a X-band SAR based on a deployable reflector antenna fed by an active phased array feed. This concept allows high performance, providing capability of electronic beam steering both in azimuth and elevation planes, improving operational performance over a purely mechanically steered SAR system. Instrument provides both STRIPMAP and SPOTLIGHT modes, and thanks to very high gain antenna, can also provide a real maritime surveillance mode based on a patented Low PRF radar mode. Further developments are in progress considering missions based on Microsatellites technology, which can provide effective solutions for different user needs, such as Operational responsiveness, low cost constellations, distributed observation concept, flying formations, and can be conceived for applications in the field of Observation, Atmosphere sensing, Intelligence, Surveillance, Reconnaissance (ISR), Signal Intelligence. To satisfy these requirements, flexibility of small platforms is a key driver and especially new miniaturization technologies able to optimize the performance. An overview new micros-satellite (based on NIMBUS

Using Satellite Observations to Infer the Relationship Between Cold Pools and Subsequent Convection Development

NASA Technical Reports Server (NTRS)

Elsaesser, Gregory

2015-01-01

Cold pools are increasingly being recognized as important players in the evolution of both shallow and deep convection; hence, the incorporation of cold pool processes into a number of recently developed convective parameterizations. Unfortunately, observations serving to inform cold pool parameterization development are limited to select field programs and limited radar domains. However, a number of recent studies have noted that cold pools are often associated with arcs-lines of shallow clouds traversing 10 100 km in visible satellite imagery. Boundary layer thermodynamic perturbations are plausible at such scales, coincident with such mesoscale features. Atmospheric signatures of features at these spatial scales are potentially observable from satellites. In this presentation, we discuss recent work that uses multi-sensor, high-resolution satellite products for observing mesoscale wind vector fluctuations and boundary layer temperature depressions attributed to cold pools produced by antecedent convection. The relationship to subsequent convection as well as convective system longevity is discussed. As improvements in satellite technology occur and efforts to reduce noise in high-resolution orbital products progress, satellite pixel level (10 km) thermodynamic and dynamic (e.g. mesoscale convergence) parameters can increasingly serve as useful benchmarks for constraining convective parameterization development, including for regimes where organized convection contributes substantially to the cloud and rainfall climatology.

Satellite-based GNSS-R observations from TDS-1 for soil moisture studies in agricultural vegetation landscapes

NASA Astrophysics Data System (ADS)

Liu, P. W.; Clarizia, M. P.; Judge, J.; Camps, A.; Ruf, C. S.; Bongiovanni, T. E.

2015-12-01

Soil moisture (SM) is a critical factor governing the water and energy fluxes at the land surface that are important for near-term climate forecasting, drought monitoring, crop yield estimation, and better water resources management. Remotely sensed observations at microwave frequencies are the most sensitive to changes of water in the soil. Particularly, frequencies at L-band (1-2 GHz) have been widely used for SM studies under the vegetated land covers because of their minimal atmospheric interference and attenuation by vegetation, allowing observations from the soil surface. In addition to current satellite based microwave sensors, such as the Soil Moisture Active Passive (SMAP) missions, the Global Navigation Satellite System-Reflectometry technique is capable of observing the GNSS signal reflected from the terrain that contains combined information of soil and vegetation characteristics. The technique has recently attracted attention for global SM monitoring because its receiver is small in size and light weight and can be on board the low orbit, small satellites with low power consumption and low cost. Therefore the GNSS-R remote sensing may lead to affordable multi-satellite constellations that enable improved temporal resolution for highly dynamic hydrologic conditions. The current UK Technology Demonstration Satellite (TDS-1) has been providing global GNSS-R observations since September 2014 for experimental purposes and the receiver is accessed and operated for 2 days during every 8-day cycle. In the near future, the NASA Cyclone GNSS (CYGNSS) mission, scheduled to be launched in 2016, will consist of 8 satellites observing GPS L1 signal at a frequency of 1.5754 GHz with a spatial resolution of 10-25 km and a temporal resolution of < 12 hours. The goal of this study is to understand the impacts of SM and characteristics of agricultural vegetation on the forward scattering mechanisms of satellite-based GNSS-R observations. The GNSS-R observations from TDS

Verification of NWP Cloud Properties using A-Train Satellite Observations

NASA Astrophysics Data System (ADS)

Kucera, P. A.; Weeks, C.; Wolff, C.; Bullock, R.; Brown, B.

2011-12-01

Recently, the NCAR Model Evaluation Tools (MET) has been enhanced to incorporate satellite observations for the verification of Numerical Weather Prediction (NWP) cloud products. We have developed tools that match fields spatially (both in the vertical and horizontal dimensions) to compare NWP products with satellite observations. These matched fields provide diagnostic evaluation of cloud macro attributes such as vertical distribution of clouds, cloud top height, and the spatial and seasonal distribution of cloud fields. For this research study, we have focused on using CloudSat, CALIPSO, and MODIS observations to evaluate cloud fields for a variety of NWP fields and derived products. We have selected cases ranging from large, mid-latitude synoptic systems to well-organized tropical cyclones. For each case, we matched the observed cloud field with gridded model and/or derived product fields. CloudSat and CALIPSO observations and model fields were matched and compared in the vertical along the orbit track. MODIS data and model fields were matched and compared in the horizontal. We then use MET to compute the verification statistics to quantify the performance of the models in representing the cloud fields. In this presentation we will give a summary of our comparison and show verification results for both synoptic and tropical cyclone cases.

An analysis of the upper atmospheric wind observed by LOGACS. [satellite Low-G Accelerometer Calibration System

NASA Technical Reports Server (NTRS)

Wu, S. T.; Matsushita, S.; Devries, L. L.

1974-01-01

Wind velocities at 140 to 200 km altitude were observed by a low-g accelerometer calibration system (LOGACS) flown on an Agena satellite during a geomagnetic storm. An interesting wind reversal observed by the satellite at auroral latitudes is satisfactorily explained by the neutral air motion caused by the E x B drift deduced from the ground-based geomagnetic data recorded at stations near the meridian of the satellite orbit.

Observing iodine monoxide from satellite

NASA Astrophysics Data System (ADS)

Schoenhardt, Anja; Richter, Andreas; Begoin, Mathias; Wittrock, Folkard; Burrows, John P.

Iodine and iodine monoxide (IO) belong to the group of reactive halogen species, and they may impact on atmospheric chemical composition and the radiation budget. Vice versa, sur-rounding conditions may influence the emissions and pathways of iodine compounds. Although atmospheric amounts of iodine are typically fairly small, the impact may still be substantial. Iodine radicals are photolytically released from precursors and may then cause catalytic ozone depletion. In this reaction with ozone, IO is produced, a molecule which plays a central role in the iodine cycling. Via self reactions of IO, higher iodine oxides form and initiate the formation of new particles, which may change the atmospheric radiation balance. Apart from that, many living species, including human beings, vertebrates in general, but also micro-and macroalgae species, e.g., depend on the supply with iodine. Consequently, it is necessary to understand the cycling of iodine through the different components of the Earth system. Although increas-ing research effort in the form of field, laboratory and modeling studies has strongly improved our knowledge and understanding of iodine abundances and impact, still many open questions remain. The relevance of iodine on a global scale is not well known yet; sources are not well quantified and release processes are not fully understood. Since recently, IO may be observed from space by the SCIAMACHY instrument on the EN-VISAT satellite, which is in a near-polar, sun-synchronous orbit. Nadir observations from SCIAMACHY have been analysed for the IO absorption signature in the visible wavelength range for several mission years. IO amounts are typically close to the limit of detectability of SCIAMACHY. Detecting such small quantities, careful attention needs to be paid to system-atic errors, spectral correlations and resulting retrieval artefacts. Subsequently, appropriate temporal averaging is utilised to improve the signal-to-noise ratio. The resulting

Results of Observations over Jupiter's Galilean Satellites

NASA Astrophysics Data System (ADS)

Chigladze, Revaz; Tateshvili, Maia

The work describes the polarization properties of the light reflected from the surfaces of Galileo Jupiter's satellites, with their physical characteristics studied based on their analysis. Europe turned out to have the most homogeneous, and Callisto has the least homogeneous. Time variations are the most typical to satellite Io what must be the result of the volcanic actions on the satellite surface.

Satellite observations of temporal terrestrial features

NASA Technical Reports Server (NTRS)

Rabchevsky, G. A.

1972-01-01

The application of satellite data to earth resources and environmental studies and the effects of resolution of the photographs and imagery are discussed. The nature of the data acquired by manned space flight and unmanned satellites is described. Specific applications of remotely sensed data for oceanography, hydrology, geography, and geology are examined.

The Role of Satellite Earth Observation Data in Monitoring and Verifying International Environmental Treaties

NASA Technical Reports Server (NTRS)

Johnston, Shaida

2004-01-01

The term verification implies compliance verification in the language of treaty negotiation and implementation, particularly in the fields of disarmament and arms control. The term monitoring on the other hand, in both environmental and arms control treaties, has a much broader interpretation which allows for use of supporting data sources that are not necessarily acceptable or adequate for direct verification. There are many ways that satellite Earth observation (EO) data can support international environmental agreements, from national forest inventories to use in geographic information system (GIs) tools. Though only a few references to satellite EO data and their use exist in the treaties themselves, an expanding list of applications can be considered in support of multilateral environmental agreements (MEAs). This paper explores the current uses of satellite Earth observation data which support monitoring activities of major environmental treaties and draws conclusions about future missions and their data use. The scope of the study includes all phases of environmental treaty fulfillment - development, monitoring, and enforcement - and includes a multinational perspective on the use of satellite Earth observation data for treaty support.

Stereographic observations from geosynchronous satellites - An important new tool for the atmospheric sciences

NASA Technical Reports Server (NTRS)

Hasler, A. F.

1981-01-01

Observations of cloud geometry using scan-synchronized stereo geostationary satellites having images with horizontal spatial resolution of approximately 0.5 km, and temporal resolution of up to 3 min are presented. The stereo does not require a cloud with known emissivity to be in equilibrium with an atmosphere with a known vertical temperature profile. It is shown that absolute accuracies of about 0.5 km are possible. Qualitative and quantitative representations of atmospheric dynamics were shown by remapping, display, and stereo image analysis on an interactive computer/imaging system. Applications of stereo observations include: (1) cloud top height contours of severe thunderstorms and hurricanes, (2) cloud top and base height estimates for cloud-wind height assignment, (3) cloud growth measurements for severe thunderstorm over-shooting towers, (4) atmospheric temperature from stereo heights and infrared cloud top temperatures, and (5) cloud emissivity estimation. Recommendations are given for future improvements in stereo observations, including a third GOES satellite, operational scan synchronization of all GOES satellites and better resolution sensors.

Combining XCO2 Measurements Derived from SCIAMACHY and GOSAT for Potentially Generating Global CO2 Maps with High Spatiotemporal Resolution

PubMed Central

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

Monitoring Lake and Reservoir Level: Satellite Observations, Modeling and Prediction

NASA Astrophysics Data System (ADS)

Ricko, M.; Birkett, C. M.; Adler, R. F.; Carton, J.

2013-12-01

Satellite measurements of lake and reservoir water levels complement in situ observations by providing stage information for un-gauged basins and by filling data gaps in gauge records. However, different satellite radar altimeter-derived continental water level products may differ significantly owing to choice of satellites and data processing methods. To explore the impacts of these differences, a direct comparison between three different altimeter-based surface water level estimates (USDA/NASA GRLM, LEGOS and ESA-DMU) will be presented and products validated with lake level gauge time series for lakes and reservoirs of a variety of sizes and conditions. The availability of satellite-based rainfall (i.e., TRMM and GPCP) and satellite-based lake/reservoir levels offers exciting opportunities to estimate and monitor the hydrologic properties of the lake systems. Here, a simple water balance model is utilized to relate net freshwater flux on a catchment basin to lake/reservoir level. Focused on tropical lakes and reservoirs it allows a comparison of the flux to altimetric lake level estimates. The combined use of model, satellite-based rainfall, evaporation information and reanalysis products, can be used to output water-level hindcasts and seasonal future forecasts. Such a tool is fundamental for understanding present-day and future variations in lake/reservoir levels and enabling a better understand of climatic variations on inter-annual to inter-decadal time-scales. New model-derived water level estimates of lakes and reservoirs, on regional to global scales, would assist communities with interests in climate studies focusing on extreme events, such as floods and droughts, and be important for water resources management.

Arctic Warming Signals from Satellite Observations

NASA Technical Reports Server (NTRS)

Comiso, Josefino C.

2005-01-01

Global warming signals are expected to be amplified in the Arctic primarily because of ice-albedo feedback associated with the high reflectivity of ice and snow that blankets much of the region. The Arctic had been a poorly explored territory basically because of its general inaccessibility on account of extremely harsh weather conditions and the dominant presence of thick perennial ice in the region. The advent of satellite remote sensing systems since the 1960s, however, enabled the acquisition of synoptic data that depict in good spatial detail the temporal changes of many Arctic surface parameters. Among the surface parameters that have been studied using space based systems are surface temperature, sea ice concentration, snow cover, surface albedo and phytoplankton concentration. Associated atmospheric parameters, such as cloud cover, temperature profile, ozone concentration, and aerosol have also been derived. Recent observational and phenomenological studies have indeed revealed progressively changing conditions in the Arctic during the last few decades (e g , Walsh et al. 1996; Serreze et al 2000; Comiso and Parkinson 2004). The changes included declines in the extent and area of surfaces covered by sea ice and snow, increases in melt area over the Greenland ice sheets, thawing of the permafrost, warming in the troposphere, and retreat of the glaciers. These observations are consistent with the observed global warming that has been associated with the increasing concentration of greenhouse gases in the atmosphere (Karl and Trenberth 2003) and confirmed by modeling studies (Holland and Bitz, 2003). The Arctic system, however, is still not well understood complicated by a largely fluctuating wind circulation and atmospheric conditions (Proshutinsky and Johnson 1997) and controlled by what is now known as the Arctic Oscillation (AO) which provides a measure of the strength of atmospheric activities in the region (Thompson and Wallace 1998). Meanwhile, the

VizieR Online Data Catalog: 1995 Saturnian satellite observations (Vienne+, 2001)

NASA Astrophysics Data System (ADS)

Vienne, A.; Thuillot, W.; Veiga, C. H.; Arlot, J.-E.; Vieira Martins, R.

2001-11-01

6006 differential positions of the main Saturnian satellites issued from astrometric measurements of CCD observations performed in 1995 at the Laboratorio Nacional de Astrofisica at Itajuba in Brazil. Most of these frames have no reference stars, then we applied an inter-satellites reduction. We have used the positions of Tethys, Dione, Rhea and Titan given by TASS1.7 to determine the scale factor and the orientation of the receptor (1995A&A...297..588V, 1997 Cat. ). The comparison of the observed positions and the computed positions shows that the dispersion of the observations is 0.07". Furthermore, the quality and the number of the positions of the satellites not used in the calibration is good: 0.08" for the 216 positions of Mimas, 0.14" for Hyperion (324), 0.11" for Iapetus (524). The format and the conventions of the present catalog are very near to the one of Strugnell & Taylor (1990A&AS...83..289S). The coordinates are given apart from a scale factor and from a rotation, but all astrometric corrections are done. So, these positions are really astrometric ones in that meaning that, no astrometric consideration is necessary to use them, even if one wants to touch up the calibration. Nevertheless, the raw pixels are also given in order to allow anyone to reduce again the frames. (1 data file).

Applications of neural network methods to the processing of earth observation satellite data.

PubMed

Loyola, Diego G

2006-03-01

The new generation of earth observation satellites carries advanced sensors that will gather very precise data for studying the Earth system and global climate. This paper shows that neural network methods can be successfully used for solving forward and inverse remote sensing problems, providing both accurate and fast solutions. Two examples of multi-neural network systems for the determination of cloud properties and for the retrieval of total columns of ozone using satellite data are presented. The developed algorithms based on multi-neural network are currently being used for the operational processing of European atmospheric satellite sensors and will play a key role in related satellite missions planed for the near future.

High resolution earth observation satellites and services in the next decade a European perspective

NASA Astrophysics Data System (ADS)

Schreier, Gunter; Dech, Stefan

2005-07-01

Projects to use very high resolution optical satellite sensor data started in the late 90s and are believed to be the major driver for the commercialisation of earth observation. The global political security situation and updated legislative frameworks created new opportunities for high resolution, dual use satellite systems. In addition to new optical sensors, very high resolution synthetic aperture radars will become in the next few years an important component in the imaging satellite fleet. The paper will review the development in this domain so far, and give perspectives on future emerging markets and opportunities. With dual-use satellite initiatives and new political frameworks agreed between the European Commission and the European Space Agency (ESA), the European market becomes very attractive for both service suppliers and customers. The political focus on "Global Monitoring for Environment and Security" (GMES) and the "European Defence and Security Policy" drive and amplify this demand which ranges from low resolution climate monitoring to very high resolution reconnaissance tasks. In order to create an operational and sustainable GMES in Europe by 2007, the European infrastructure need to be adapted and extended. This includes the ESA SENTINEL and OXYGEN programmes, aiming for a fleet of earth observation satellites and an open and operational earth observation ground segment. The harmonisation of national and regional geographic information is driven by the European Commission's INSPIRE programme. The necessary satellite capacity to complement existing systems in the delivery of space based data required for GMES is currently under definition. Embedded in a market with global competition and in the global political framework of a Global Earth Observation System of Systems, European companies, agencies and research institutions are now contributing to this joint undertaking. The paper addresses the chances, risks and options for the future.

Inference of Spatiotemporal Distribution of Black Carbon Aerosols over Northern Pacific from Satellite Observations (2005-2012)

NASA Astrophysics Data System (ADS)

Liu, J.; Li, Z.; Mauzerall, D. L.; Fan, S.; Horowitz, L. W.; He, C.; Yi, K.; Tao, S.

2015-12-01

Knowledge on the spatiotemporal distribution of black carbon aerosol over the Northern Pacific is limited by a deficiency of observations. The HIAPER Pole-to-Pole Observation (HIPPO) program from 2009 to 2011 is the most comprehensive data source available and it reveals a 2 to 10 times overestimates of BC by current global models. Incorporation and assimilation of more data sources is needed to increase our understanding of the spatiotemporal distribution of black carbon aerosol and its corresponding climate effects. Based on measurements from aircraft campaigns and satellites, a robust association is observed between BC concentrations and satellite retrieved CO, tropospheric NO2, and aerosol optical depth (AOD) (R2 > 0.7). Such robust relationships indicate that BC aerosols share a similar emission sources, evolution processes and transport characteristics with other pollutants measured by satellite observations. It also establishes a basis to derive a satellite-based proxy (BC*) over remote oceans. The inferred satellite-based BC* shows that Asian export events in spring bring much more BC aerosols to the mid-Pacific than occurs in other seasons. In addition, inter-annual variability of BC* is seen over the Northern Pacific, with abundances correlated to the springtime Pacific/North American (PNA) index. The inferred BC* dataset also indicates a widespread overestimation of BC loadings by models over most remote oceans beyond the Pacific. Our method presents a novel approach to infer BC concentrations by combining satellite and aircraft observations.

Fast emission estimates in China and South Africa constrained by satellite observations

NASA Astrophysics Data System (ADS)

Mijling, Bas; van der A, Ronald

2013-04-01

Emission inventories of air pollutants are crucial information for policy makers and form important input data for air quality models. Unfortunately, bottom-up emission inventories, compiled from large quantities of statistical data, are easily outdated for emerging economies such as China and South Africa, where rapid economic growth change emissions accordingly. Alternatively, top-down emission estimates from satellite observations of air constituents have important advantages of being spatial consistent, having high temporal resolution, and enabling emission updates shortly after the satellite data become available. However, constraining emissions from observations of concentrations is computationally challenging. Within the GlobEmission project (part of the Data User Element programme of ESA) a new algorithm has been developed, specifically designed for fast daily emission estimates of short-lived atmospheric species on a mesoscopic scale (0.25 × 0.25 degree) from satellite observations of column concentrations. The algorithm needs only one forward model run from a chemical transport model to calculate the sensitivity of concentration to emission, using trajectory analysis to account for transport away from the source. By using a Kalman filter in the inverse step, optimal use of the a priori knowledge and the newly observed data is made. We apply the algorithm for NOx emission estimates in East China and South Africa, using the CHIMERE chemical transport model together with tropospheric NO2 column retrievals of the OMI and GOME-2 satellite instruments. The observations are used to construct a monthly emission time series, which reveal important emission trends such as the emission reduction measures during the Beijing Olympic Games, and the impact and recovery from the global economic crisis. The algorithm is also able to detect emerging sources (e.g. new power plants) and improve emission information for areas where proxy data are not or badly known (e

Improving the Transition of Earth Satellite Observations from Research to Operations

NASA Technical Reports Server (NTRS)

Goodman, Steven J.; Lapenta, William M.; Jedlovec, Gary J.

2004-01-01

There are significant gaps between the observations, models, and decision support tools that make use of new data. These challenges include: 1) Decreasing the time to incorporate new satellite data into operational forecast assimilation systems, 2) Blending in-situ and satellite observing systems to produce the most accurate and comprehensive data products and assessments, 3) Accelerating the transition from research to applications through national test beds, field campaigns, and pilot demonstrations, and 4) Developing the partnerships and organizational structures to effectively transition new technology into operations. At the Short-term Prediction Research and Transition (SPORT) Center in Huntsville, Alabama, a NASA-NOAA-University collaboration has been developed to accelerate the infusion of NASA Earth science observations, data assimilation and modeling research into NWS forecast operations and decision-making. The SPoRT Center research focus is to improve forecasts through new observation capability and the regional prediction objectives of the US Weather Research Program dealing with 0-1 day forecast issues such as convective initiation and 24-hr quantitative precipitation forecasting. The near real-time availability of high-resolution experimental products of the atmosphere, land, and ocean from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Advanced Infrared Spectroradiometer (AIRS), and lightning mapping systems provide an opportunity for science and algorithm risk reduction, and for application assessment prior to planned observations from the next generation of operational low Earth orbiting and geostationary Earth orbiting satellites. This paper describes the process for the transition of experimental products into forecast operations, current products undergoing assessment by forecasters, and plans for the future. The SPoRT Web page is at (http://www.ghcc.msfc.nasa.gov/sport).

Imaging artificial satellites: An observational challenge

NASA Astrophysics Data System (ADS)

Smith, D. A.; Hill, D. C.

2016-10-01

According to the Union of Concerned Scientists, as of the beginning of 2016 there are 1381 active satellites orbiting the Earth, and the United States' Space Surveillance Network tracks about 8000 manmade orbiting objects of baseball-size and larger. NASA estimates debris larger than 1 cm to number more than half a million. The largest ones can be seen by eye—unresolved dots of light that move across the sky in minutes. For most astrophotographers, satellites are annoying streaks that can ruin hours of work. However, capturing a resolved image of an artificial satellite can pose an interesting challenge for a student, and such a project can provide connections between objects in the sky and commercial and political activities here on Earth.

Ionospheric Density Enhancements at Low and Middle Latitudes during Superstorms Observed from Multiple Satellites

NASA Astrophysics Data System (ADS)

Lei, J.; Wang, W.; Burns, A. G.; Yue, X.

2014-12-01

The total electron content (TEC) data measured by the Jason, CHAMP, GRACE and SAC-C satellites, the in-situ electron densities from CHAMP and GRACE, and the vertical E×B drifts from the ROCSAT satellite are utilized to examine the ionospheric response to superstorms. The combination of observations from multiple satellites provides a unique global view of positive ionospheric storm effect at low and middle latitudes, especially over Oceans and under sunlit conditions during the main phases of the storms. In this talk, we will focus on the morphology, evolution and driving mechanisms of the storm-time ionosphere and explore the relative contributions of the horizontal and vertical transport effects to the observed positive storm phase at different latitudes.

Scaling Issues Between Plot and Satellite Radiobrightness Observations of Arctic Tundra

NASA Technical Reports Server (NTRS)

Kim, Edward J.; England, Anthony W.; Judge, Jasmeet; Zukor, Dorothy J. (Technical Monitor)

2000-01-01

Data from generation of satellite microwave radiometer will allow the detection of seasonal to decadal changes in the arctic hydrology cycle as expressed in temporal and spatial patterns of moisture stored in soil and snow This nw capability will require calibrated Land Surface Process/Radiobrightness (LSP/R) model for the principal terrains found in the circumpolar Arctic. These LSP/R models can than be used in weak constraint. Dimensional Data Assimilation (DDA)of the daily satellite observation to estimate temperature and moisture profiles within the permafrost in active layer.

Sensor Web Interoperability Testbed Results Incorporating Earth Observation Satellites

NASA Technical Reports Server (NTRS)

Frye, Stuart; Mandl, Daniel J.; Alameh, Nadine; Bambacus, Myra; Cappelaere, Pat; Falke, Stefan; Derezinski, Linda; Zhao, Piesheng

2007-01-01

This paper describes an Earth Observation Sensor Web scenario based on the Open Geospatial Consortium s Sensor Web Enablement and Web Services interoperability standards. The scenario demonstrates the application of standards in describing, discovering, accessing and tasking satellites and groundbased sensor installations in a sequence of analysis activities that deliver information required by decision makers in response to national, regional or local emergencies.

Al Gore attends Fall Meeting session on Earth observing satellite

NASA Astrophysics Data System (ADS)

Richman, Barbara T.

2011-12-01

Former U.S. vice president Al Gore, making unscheduled remarks at an AGU Fall Meeting session, said, "The reason you see so many pictures" of the Deep Space Climate Observatory (DSCOVR) satellite at this session is "that it already has been built." However, "because one of its primary missions was to help document global warming, it was canceled. So for those who are interested in struggling against political influence," Gore said, "the benefits have been documented well here." Gore made his comments after the third oral presentation at the 8 December session entitled "Earth Observations From the L1 (Lagrangian Point No. 1)," which focused on the capabilities of and progress on refurbishing DSCOVR. The satellite, formerly called Triana, had been proposed by Gore in 1998 to collect climate data. Although Triana was built, it was never launched: Congress mandated that before the satellite could be sent into space the National Academies of Science needed to confirm that the science it would be doing was worthwhile. By the time the scientific validation was complete, the satellite "was no longer compatible with the space shuttle manifest," Robert C. Smith, program manager for strategic integration at the NASA Goddard Space Flight Center, told Eos.

Climate Model Diagnostic and Evaluation: With a Focus on Satellite Observations

NASA Technical Reports Server (NTRS)

Waliser, Duane

2011-01-01

Each year, we host a summer school that brings together the next generation of climate scientists - about 30 graduate students and postdocs from around the world - to engage with premier climate scientists from the Jet Propulsion Laboratory and elsewhere. Our yearly summer school focuses on topics on the leading edge of climate science research. Our inaugural summer school, held in 2011, was on the topic of "Using Satellite Observations to Advance Climate Models," and enabled students to explore how satellite observations can be used to evaluate and improve climate models. Speakers included climate experts from both NASA and the National Oceanic and Atmospheric Administration (NOAA), who provided updates on climate model diagnostics and evaluation and remote sensing of the planet. Details of the next summer school will be posted here in due course.

MethaneSat: Detecting Methane Emissions in the Barnett Shale Region

NASA Astrophysics Data System (ADS)

Propp, A. M.; Benmergui, J. S.; Turner, A. J.; Wofsy, S. C.

2017-12-01

In this study, we investigate the new information that will be provided by MethaneSat, a proposed satellite that will measure the total column dry-air mole fraction of methane at 1x1 km or 2x2 km spatial resolution with 0.1-0.2% random error. We run an atmospheric model to simulate MethaneSat's ability to characterize methane emissions from the Barnett Shale, a natural gas province in Texas. For comparison, we perform observation system simulation experiments (OSSEs) for MethaneSat, the National Oceanic and Atmospheric administration (NOAA) surface and aircraft network, and Greenhouse Gases Observing Satellite (GOSAT). The results demonstrate the added benefit that MethaneSat would provide in our efforts to monitor and report methane emissions. We find that MethaneSat successfully quantifies total methane emissions in the region, as well as their spatial distribution and steep gradients. Under the same test conditions, both the NOAA network and GOSAT fail to capture this information. Furthermore, we find that the results for MethaneSat depend far less on the prior emission estimate than do those for the other observing systems, demonstrating the benefit of high sampling density. The results suggest that MethaneSat would be an incredibly useful tool for obtaining detailed methane emission information from oil and gas provinces around the world.

Constraining the low-cloud optical depth feedback at middle and high latitudes using satellite observations

DOE PAGES

Terai, C. R.; Klein, S. A.; Zelinka, M. D.

2016-08-26

The increase in cloud optical depth with warming at middle and high latitudes is a robust cloud feedback response found across all climate models. This study builds on results that suggest the optical depth response to temperature is timescale invariant for low-level clouds. The timescale invariance allows one to use satellite observations to constrain the models' optical depth feedbacks. Three passive-sensor satellite retrievals are compared against simulations from eight models from the Atmosphere Model Intercomparison Project (AMIP) of the 5th Coupled Model Intercomparison Project (CMIP5). This study confirms that the low-cloud optical depth response is timescale invariant in the AMIPmore » simulations, generally at latitudes higher than 40°. Compared to satellite estimates, most models overestimate the increase in optical depth with warming at the monthly and interannual timescales. Many models also do not capture the increase in optical depth with estimated inversion strength that is found in all three satellite observations and in previous studies. The discrepancy between models and satellites exists in both hemispheres and in most months of the year. A simple replacement of the models' optical depth sensitivities with the satellites' sensitivities reduces the negative shortwave cloud feedback by at least 50% in the 40°–70°S latitude band and by at least 65% in the 40°–70°N latitude band. Furthermore, based on this analysis of satellite observations, we conclude that the low-cloud optical depth feedback at middle and high latitudes is likely too negative in climate models.« less

Constraining the low-cloud optical depth feedback at middle and high latitudes using satellite observations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terai, C. R.; Klein, S. A.; Zelinka, M. D.

The increase in cloud optical depth with warming at middle and high latitudes is a robust cloud feedback response found across all climate models. This study builds on results that suggest the optical depth response to temperature is timescale invariant for low-level clouds. The timescale invariance allows one to use satellite observations to constrain the models' optical depth feedbacks. Three passive-sensor satellite retrievals are compared against simulations from eight models from the Atmosphere Model Intercomparison Project (AMIP) of the 5th Coupled Model Intercomparison Project (CMIP5). This study confirms that the low-cloud optical depth response is timescale invariant in the AMIPmore » simulations, generally at latitudes higher than 40°. Compared to satellite estimates, most models overestimate the increase in optical depth with warming at the monthly and interannual timescales. Many models also do not capture the increase in optical depth with estimated inversion strength that is found in all three satellite observations and in previous studies. The discrepancy between models and satellites exists in both hemispheres and in most months of the year. A simple replacement of the models' optical depth sensitivities with the satellites' sensitivities reduces the negative shortwave cloud feedback by at least 50% in the 40°–70°S latitude band and by at least 65% in the 40°–70°N latitude band. Furthermore, based on this analysis of satellite observations, we conclude that the low-cloud optical depth feedback at middle and high latitudes is likely too negative in climate models.« less

Satellite Observations of Desert Dust-induced Himalayan Snow Darkening

NASA Technical Reports Server (NTRS)

Gautam, Ritesh; Hsu, N. Christina; Lau, William K.-M.; Yasunari, Teppei J.

2013-01-01

The optically thick aerosol layer along the southern edge of the Himalaya has been subject of several recent investigations relating to its radiative impacts on the South Asian summer monsoon and regional climate forcing. Prior to the onset of summer monsoon, mineral dust from southwest Asian deserts is transported over the Himalayan foothills on an annual basis. Episodic dust plumes are also advected over the Himalaya, visible as dust-laden snow surface in satellite imagery, particularly in western Himalaya. We examined spectral surface reflectance retrieved from spaceborne MODIS observations that show characteristic reduction in the visible wavelengths (0.47 nm) over western Himalaya, associated with dust-induced solar absorption. Case studies as well as seasonal variations of reflectance indicate a significant gradient across the visible (0.47 nm) to near-infrared (0.86 nm) spectrum (VIS-NIR), during premonsoon period. Enhanced absorption at shorter visible wavelengths and the resulting VIS-NIR gradient is consistent with model calculations of snow reflectance with dust impurity. While the role of black carbon in snow cannot be ruled out, our satellite-based analysis suggests the observed spectral reflectance gradient dominated by dust-induced solar absorption during premonsoon season. From an observational viewpoint, this study underscores the importance of mineral dust deposition toward darkening of the western Himalayan snow cover, with potential implications to accelerated seasonal snowmelt and regional snow albedo feedbacks.

Arctic Sea ice, 1973-1976: Satellite passive-microwave observations

NASA Technical Reports Server (NTRS)

Parkinson, Claire L.; Comiso, Josefino C.; Zwally, H. Jay; Cavalieri, Donald J.; Gloersen, Per; Campbell, William J.

1987-01-01

The Arctic region plays a key role in the climate of the earth. The sea ice cover affects the radiative balance of the earth and radically changes the fluxes of heat between the atmosphere and the ocean. The observations of the Arctic made by the Electrically Scanning Microwave Radiometer (ESMR) on board the Nimbus 5 research satellite are summarized for the period 1973 through 1976.

Satellite scheduling considering maximum observation coverage time and minimum orbital transfer fuel cost

NASA Astrophysics Data System (ADS)

Zhu, Kai-Jian; Li, Jun-Feng; Baoyin, He-Xi

2010-01-01

In case of an emergency like the Wenchuan earthquake, it is impossible to observe a given target on earth by immediately launching new satellites. There is an urgent need for efficient satellite scheduling within a limited time period, so we must find a way to reasonably utilize the existing satellites to rapidly image the affected area during a short time period. Generally, the main consideration in orbit design is satellite coverage with the subsatellite nadir point as a standard of reference. Two factors must be taken into consideration simultaneously in orbit design, i.e., the maximum observation coverage time and the minimum orbital transfer fuel cost. The local time of visiting the given observation sites must satisfy the solar radiation requirement. When calculating the operational orbit elements as optimal parameters to be evaluated, we obtain the minimum objective function by comparing the results derived from the primer vector theory with those derived from the Hohmann transfer because the operational orbit for observing the disaster area with impulse maneuvers is considered in this paper. The primer vector theory is utilized to optimize the transfer trajectory with three impulses and the Hohmann transfer is utilized for coplanar and small inclination of non-coplanar cases. Finally, we applied this method in a simulation of the rescue mission at Wenchuan city. The results of optimizing orbit design with a hybrid PSO and DE algorithm show that the primer vector and Hohmann transfer theory proved to be effective methods for multi-object orbit optimization.

The Asian Tropopause Aerosol Layer: Balloon-Borne Measurements, Satellite Observations and Modeling Approaches

NASA Technical Reports Server (NTRS)

Fairlie, T. D.; Vernier, J.-P.; Natarajan, M.; Deshler, Terry; Liu, H.; Wegner, T.; Baker, N.; Gadhavi, H.; Jayaraman, A.; Pandit, A.;

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.

Satellite Observation of El Nino Effects on Amazon Forest Phenology and Productivity

NASA Technical Reports Server (NTRS)

Asner, Gregory P.; Townsend, Alan R.; Braswell, Bobby H.

2000-01-01

Climate variability may affect the functioning of Amazon moist tropical forests, and recent modeling analyses suggest that the carbon dynamics of the region vary interannually in response to precipitation and temperature anomalies. However, due to persistent orbital and atmospheric artifacts in the satellite record, remote sensing observations have not provided quantitative evidence that climate variation affects Amazon forest phenology or productivity, We developed a method to minimize and quantify non-biological artifacts in NOAA AVHRR satellite data, providing a record of estimated forest phenological variation from 1982-1993. The seasonal Normalized Difference Vegetation Index (NDVI) amplitude (a proxy for phenology) increased throughout much of the basin during El Nino periods when rainfall was anomalously low. Wetter La Nina episodes brought consistently smaller NDVI amplitudes. Using radiative transfer and terrestrial biogeochemical models driven by these satellite data, we estimate that canopy-energy absorption and net primary production of Amazon forests varied interannually by as much as 21% and 18%, respectively. These results provide large-scale observational evidence for interannual sensitivity to El Nino of plant phenology and carbon flux in Amazon forests.

ASTER satellite observations for international disaster management

USGS Publications Warehouse

Duda, K.A.; Abrams, M.

2012-01-01

When lives are threatened or lost due to catastrophic disasters, and when massive financial impacts are experienced, international emergency response teams rapidly mobilize to provide urgently required support. Satellite observations of affected areas often provide essential insight into the magnitude and details of the impacts. The large cost and high complexity of developing and operating satellite flight and ground systems encourages international collaboration in acquiring imagery for such significant global events in order to speed delivery of critical information to help those affected, and optimize spectral, spatial, and temporal coverage of the areas of interest. The International Charter-Space and Major Disasters was established to enable such collaboration in sensor tasking during times of crisis and is often activated in response to calls for assistance from authorized users. Insight is provided from a U.S. perspective into sensor support for Charter activations and other disaster events through a description of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), which has been used to support emergency situations for over a decade through its expedited tasking and near real-time data delivery capabilities. Examples of successes achieved and challenges encountered in international collaboration to develop related systems and fulfill tasking requests suggest operational considerations for new missions as well as areas for future enhancements.

Astrometric positions for 18 irregular satellites of giant planets from 23 years of observations

NASA Astrophysics Data System (ADS)

Gomes-Júnior, A. R.; Assafin, M.; Vieira-Martins, R.; Arlot, J.-E.; Camargo, J. I. B.; Braga-Ribas, F.; da Silva Neto, D. N.; Andrei, A. H.; Dias-Oliveira, A.; Morgado, B. E.; Benedetti-Rossi, G.; Duchemin, Y.; Desmars, J.; Lainey, V.; Thuillot, W.

2015-08-01

Context. The irregular satellites of the giant planets are believed to have been captured during the evolution of the solar system. Knowing their physical parameters, such as size, density, and albedo is important for constraining where they came from and how they were captured. The best way to obtain these parameters are observations in situ by spacecrafts or from stellar occultations by the objects. Both techniques demand that the orbits are well known. Aims: We aimed to obtain good astrometric positions of irregular satellites to improve their orbits and ephemeris. Methods: We identified and reduced observations of several irregular satellites from three databases containing more than 8000 images obtained between 1992 and 2014 at three sites (Observatório do Pico dos Dias, Observatoire de Haute-Provence, and European Southern Observatory - La Silla). We used the software Platform for Reduction of Astronomical Images Automatically (PRAIA) to make the astrometric reduction of the CCD frames. The UCAC4 catalog represented the International Celestial Reference System in the reductions. Identification of the satellites in the frames was done through their ephemerides as determined from the SPICE/NAIF kernels. Some procedures were followed to overcome missing or incomplete information (coordinates, date), mostly for the older images. Results: We managed to obtain more than 6000 positions for 18 irregular satellites: 12 of Jupiter, 4 of Saturn, 1 of Uranus (Sycorax), and 1 of Neptune (Nereid). For some satellites the number of obtained positions is more than 50% of what was used in earlier orbital numerical integrations. Conclusions: Comparison of our positions with recent JPL ephemeris suggests there are systematic errors in the orbits for some of the irregular satellites. The most evident case was an error in the inclination of Carme. Position tables are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http

The Potential of Clear Sky Carbon Dioxide Satellite Retrievals

NASA Astrophysics Data System (ADS)

Nelson, R.; O'Dell, C.

2013-12-01

It has been shown that neglecting scattering and absorption by aerosols and thin clouds can lead to significant errors in retrievals of the column-averaged dry-air mole fraction of carbon dioxide (XCO2) from space-based measurements of near-infrared reflected sunlight. These clear sky retrievals, which assume no aerosol effects, are desirable because of their high computational efficiency relative to common full physics retrievals. Further, clear sky retrievals may be able to make higher quality measurements relative to the full physics approach because they may introduce fewer potential biases under certain circumstances. These biases can appear when we try to retrieve clouds and aerosols in the full physics methods when there are none actually present. Recent work has shown that intelligent pre-screening can remove soundings with large light-path modifications over ocean surfaces. In this work, we test the hypothesis that intelligent pre-screening of soundings may be successfully used over land surfaces as well as oceans, which would allow clear sky retrievals to be applicable over all surfaces. We also test the hypothesis that major light path modification effects associated with aerosols can be identified based on spectral tests at 0.76, 1.6, and 2 microns. This presentation summarizes our study of both simulated data and satellite observations from the GOSAT instrument in order to assess the effectiveness of using a clear sky retrieval algorithm coupled with intelligent pre-screening to accurately measure carbon dioxide from space-borne instruments.

Improved Hydrological Decision Support System for the Lower Mekong River Basin Using Satellite-Based Earth Observations.

PubMed

Mohammed, Ibrahim Nourein; Bolten, John D; Srinivasan, Raghavan; Lakshmi, Venkat

2018-06-01

Multiple satellite-based earth observations and traditional station data along with the Soil & Water Assessment Tool (SWAT) hydrologic model were employed to enhance the Lower Mekong River Basin region's hydrological decision support system. A nearest neighbor approximation methodology was introduced to fill the Integrated Multi-satellite Retrieval for the Global Precipitation Measurement mission (IMERG) grid points from 2001 to 2014, together with the Tropical Rainfall Measurement Mission (TRMM) data points for continuous precipitation forcing for our hydrological decision support system. A software tool to access and format satellite-based earth observation systems of precipitation and minimum and maximum air temperatures was developed and is presented. Our results suggest that the model-simulated streamflow utilizing TRMM and IMERG forcing data was able to capture the variability of the observed streamflow patterns in the Lower Mekong better than model-simulated streamflow with in-situ precipitation station data. We also present satellite-based and in-situ precipitation adjustment maps that can serve to correct precipitation data for the Lower Mekong region for use in other applications. The inconsistency, scarcity, poor spatial representation, difficult access and incompleteness of the available in-situ precipitation data for the Mekong region make it imperative to adopt satellite-based earth observations to pursue hydrologic modeling.

Improved Hydrological Decision Support System for the Lower Mekong River Basin Using Satellite-Based Earth Observations

PubMed Central

Mohammed, Ibrahim Nourein; Bolten, John D.; Srinivasan, Raghavan; Lakshmi, Venkat

2018-01-01

Multiple satellite-based earth observations and traditional station data along with the Soil & Water Assessment Tool (SWAT) hydrologic model were employed to enhance the Lower Mekong River Basin region’s hydrological decision support system. A nearest neighbor approximation methodology was introduced to fill the Integrated Multi-satellite Retrieval for the Global Precipitation Measurement mission (IMERG) grid points from 2001 to 2014, together with the Tropical Rainfall Measurement Mission (TRMM) data points for continuous precipitation forcing for our hydrological decision support system. A software tool to access and format satellite-based earth observation systems of precipitation and minimum and maximum air temperatures was developed and is presented. Our results suggest that the model-simulated streamflow utilizing TRMM and IMERG forcing data was able to capture the variability of the observed streamflow patterns in the Lower Mekong better than model-simulated streamflow with in-situ precipitation station data. We also present satellite-based and in-situ precipitation adjustment maps that can serve to correct precipitation data for the Lower Mekong region for use in other applications. The inconsistency, scarcity, poor spatial representation, difficult access and incompleteness of the available in-situ precipitation data for the Mekong region make it imperative to adopt satellite-based earth observations to pursue hydrologic modeling. PMID:29938116

The PHESAT95 catalogue of observations of the mutual events of the Saturnian satellites

NASA Astrophysics Data System (ADS)

Thuillot, W.; Arlot, J.-E.; Ruatti, C.; Berthier, J.; Blanco, C.; Colas, F.; Czech, W.; Damani, M.; D'Ambrosio, V.; Descamps, P.; Dourneau, G.; Emelianov, N.; Foglia, S.; Helmer, G.; Irsmambetova, T. R.; James, N.; Laques, P.; Lecacheux, J.; Le Campion, J.-F.; Ledoux, C.; Le Floch, J.-C.; Oprescu, G.; Rapaport, M.; Riccioli, R.; Starosta, B.; Tejfel, V. G.; Trunkovsky, E. M.; Viateau, B.; Veiga, C. H.; Vu, D. T.

2001-05-01

In 1994-1996 the Sun and the Earth passed through the equatorial plane of Saturn and therefore through the orbital planes of its main satellites. During this period, phenomena involving seven of these satellites were observed. Light curves of eclipses by Saturn and of mutual eclipses and occultations were recorded by the observers of the international campaign PHESAT95 organized by the Institut de mécanique céleste, Paris, France. Herein, we report 66 observations of 43 mutual events from 16 sites. For each observation, information is given about the telescope, the receptor, the site and the observational conditions. This paper gathers together all these data and gives a first estimate of the precision providing accurate astrometric data useful for the development of dynamical models.

Middle atmosphere composition revealed by satellite observations

NASA Technical Reports Server (NTRS)

Russell, J. M., III; Solomon, S.; Mccormick, M. P.; Miller, A. J.; Barnett, J. J.; Jones, R. L.; Rusch, D. W.

1986-01-01

A series of plots that describe the state of the stratosphere and to some degree, the mesosphere as revealed by satellite observations are shown. The pertinent instrument features, spatial and temporal coverage, and details of accuracy and precision for the experiments providing the data were described. The main features of zonal mean cross sections and polar stereographic projections were noted and intercomparisons were discussed where a parameter was measured by more than one experiment. The main purpose was to collect the available data in one place and provide enough inforamation on limitations or cautions about the data so that they could be used in model comparisons and science studies.

Committee on Earth Observation Satellites (CEOS) perspectives about the GEO Supersite initiative

NASA Astrophysics Data System (ADS)

Lengert, Wolfgang; Zoffoli, Simona; Giguere, Christine; Hoffmann, Joern; Lindsay, Francis; Seguin, Guy

2014-05-01

This presentation is outlining the effort of the Committee on Earth Observation Satellites (CEOS) using its global collaboration structure to support implementing the GEO priority action DI-01 Informing Risk Management and Disaster Reduction addressing the component: C2 Geohazards Monitoring, Alert, and Risk Assessment. A CEOS Supersites Coordination Team (SCT) has been established in order to make best use of the CEOS global satellite resources. For this, the CEOS SCT has taken a holistic view on the science data needs and availability of resources, considering the constraints and exploitation potentials of synergies. It is interfacing with the Supersites Science Advisory Group and the Principle Investigators to analyze how the satellite data associated with seismic and Global Navigation Satellite System (GNSS) data can support national authorities and policy makers in risk assessment and the development of mitigation strategies. CEOS SCT aims to support the establishment of a fully integrated approach to geohazards monitoring, based on collaboration among existing networks and international initiatives, using new instrumentation such as in-situ sensors, and aggregating space (radar, optical imagery) and ground-based (subsurface) observations. The three Supersites projects which are funded under the EC FP7 action, namely (i) FUTUREVOLC: A European volcanological supersite in Iceland: a monitoring system and network for the future Geohazards Monitoring, Alert, and Risk Assessment, (ii) MARsite: New Directions in Seismic Hazard assessment through Focused Earth Observation in the Marmara Supersite, (iii) MED-SUV: MEDiterranean Volcanoes and related seismic risks, have been examined as a vehicle to fulfill these ambitious objectives. FUTUREVOLC has already been granted CEOS support. This presentation will outline CEOS agreed process and criteria applied by the Supersites Coordination Team (SCT), for selecting these Supersites in the context of the GSNL initiative, as

A Regional Climate Model Evaluation System based on Satellite and other Observations

NASA Astrophysics Data System (ADS)

Lean, P.; Kim, J.; Waliser, D. E.; Hall, A. D.; Mattmann, C. A.; Granger, S. L.; Case, K.; Goodale, C.; Hart, A.; Zimdars, P.; Guan, B.; Molotch, N. P.; Kaki, S.

2010-12-01

Regional climate models are a fundamental tool needed for downscaling global climate simulations and projections, such as those contributing to the Coupled Model Intercomparison Projects (CMIPs) that form the basis of the IPCC Assessment Reports. The regional modeling process provides the means to accommodate higher resolution and a greater complexity of Earth System processes. Evaluation of both the global and regional climate models against observations is essential to identify model weaknesses and to direct future model development efforts focused on reducing the uncertainty associated with climate projections. However, the lack of reliable observational data and the lack of formal tools are among the serious limitations to addressing these objectives. Recent satellite observations are particularly useful as they provide a wealth of information on many different aspects of the climate system, but due to their large volume and the difficulties associated with accessing and using the data, these datasets have been generally underutilized in model evaluation studies. Recognizing this problem, NASA JPL / UCLA is developing a model evaluation system to help make satellite observations, in conjunction with in-situ, assimilated, and reanalysis datasets, more readily accessible to the modeling community. The system includes a central database to store multiple datasets in a common format and codes for calculating predefined statistical metrics to assess model performance. This allows the time taken to compare model simulations with satellite observations to be reduced from weeks to days. Early results from the use this new model evaluation system for evaluating regional climate simulations over California/western US regions will be presented.

Expedition for the observation of a deployment of the american satellite echo II in the winter 1963

NASA Astrophysics Data System (ADS)

Karetnikov, V. G.; Mandel, O. E.

1999-08-01

One of the first cooperative projects USSR-USA in teh field of a satellite astronomy was organization of observations of a brightness of a satellite -baloon EchoII in accordance with filling it by gas after an output satellite into orbit. The expedition was conducted under aegis of Astronomical Council of Academy of Sciences of teh USSR,the coordinator of the program was V. M. Grigorevskij- at that time a senior lecturer of Kishinev (Chisinau) University. Four groups of the observers were directed to four points -Ufa, Vyatka (Kirov region), Syktyvkar, Norilsk- located under trajectory of the satellite on it the first orbits. The authors of the given message entered also in the staff of expedition. Duie to good weather conditions it was possible to execute the observations. V.Grigorevskij and G. Leikin have determined the period of rotation of the satellite about the axis and parameters of orientation. The expedition, except scientific value in strenghtening of international cooperation in the field of space researches.

NASA Satellite Observations: A Unique Asset for the Study of the Environment and Implications for Public Health

NASA Technical Reports Server (NTRS)

Estes Sue M.

2010-01-01

This slide presentation highlights how satellite observation systems are assets for studying the environment in relation to public health. It includes information on current and future satellite observation systems, NASA's public health and safety research, surveillance projects, and NASA's public health partners.

Observing Planetary Rings and Small Satellites with the James Webb Space Telescope: Science Justification and Observation Requirements

NASA Technical Reports Server (NTRS)

Tiscareno, Matthew S.; Showalter, Mark R.; French, Richard G.; Burns, Joseph A.; Cuzzi, Jeffrey N.; de Pater, Imke; Hamilton, Douglas P.; Hedman, Matthew M.; Nicholson, Philip D.; Tamayo, Daniel;

A portable FTS measurements during GOSAT and OCO-2 joint campaign in Western US 2017

NASA Astrophysics Data System (ADS)

Shiomi, K.; Kikuchi, N.; Kuze, A.; Hashimoto, M.; Suto, H.; Kataoka, F.; Kasai, K.; Arai, T.; Oshio, H.; Ohyama, H.; Morino, I.; Hori, A.; Hedelius, J.; Parker, H. A.; Roehl, C. M.; Wennberg, P. O.; Leifer, I.; Iraci, L. T.; Bruegge, C. J.; Schwandner, F. M.; Osterman, G. B.; Crisp, D.

2017-12-01

The column-average dry air mole fractions of carbon dioxide (XCO2), methane (XCH4) and carbon monoxide (XCO) were measured from the surface using direct sunlight at near-IR wavelengths. Simultaneous detection of CO is helpful to characterize CO2 source type. We measured XCO along with XCO2 and XCH4 using an upgraded portable Fourier transform spectrometer (FTS), EM27/SUN, in western US field experiments at 1) Caltech and JPL, in Pasadena, a northern Los Angeles suburb, 2) Railroad Valley (RRV), a desert playa in Nevada, and 3) Salton Sea, a terminal high-salinity lake in southern California's Imperial Valley. These measurements were conducted during the GOSAT/OCO-2 joint campaign in the early summer of 2017. Before and after US shipments, the JAXA EM27 was compared with the NIES EM27 and Tsukuba TCCON station to quantify the measurement bias and to identify any unanticipated changes. After US shipment, the JAXA EM27 was compared with the Caltech EM27 and the Caltech TCCON station with the NASA-Dryden TCCON station, which is now located at JPL for OCO-3 pre-flight test comparisons. At RRV, we obtained not only the EM27 data but also atmospheric profile of pressure, temperature and humidity by radiosonde and aerosol optical thickness (AOT) by Microtops. Then, we deployed the EM27 on the south side of the Salton Sea, where agriculture, active volcanism and geothermal power plants might produce CO2 and CH4 as sources. A large CO enhancement originating from wildfires was serendipitously measured in conjunction with a large AOT measured by the Microtops. The JAXA EM27 measurements at Pasadena, RRV and Salton Sea were taken in conjunction with GOSAT and OCO-2 overpass targets and are being used to assess the value of the EM27 as a portable transfer standard for validating space based measurements of greenhouse gases.

Gravity waves in the thermosphere observed by the AE satellites

NASA Technical Reports Server (NTRS)

Gross, S. H.; Reber, C. A.; Huang, F. T.

1983-01-01

Atmospheric Explorer (AE) satellite data were used to investigate the spectra characteristics of wave-like structure observed in the neutral and ionized components of the thermosphere. Power spectral analysis derived by the maximum entropy method indicate the existence of a broad spectrum of scale sizes for the fluctuations ranging from tens to thousands of kilometers.

Evaluation of methods to derive green-up dates based on daily NDVI satellite observations

NASA Astrophysics Data System (ADS)

Doktor, Daniel

2010-05-01

Bridging the gap between satellite derived green-up dates and in situ phenological observations has been the purpose of many studies over the last decades. Despite substantial advancements in satellite technology and data quality checks there is as yet no universally accepted method for extracting phenological metrics based on satellite derived vegetation indices. Dependent on the respective method derived green-up dates can vary up to serveral weeks using identical data sets. Consequently, it is difficult to compare various studies and to accurately determine an increased vegetation length due to changing temperature patterns as observed by ground phenological networks. Here, I compared how the characteristic NDVI increase over temperate deciduous forests in Germany in spring relates to respective budburst events observed on the ground. MODIS Terra daily surface reflectances with a 250 m resolution (2000-2008) were gathered to compute daily NDVI values. As ground truth, observations of the extensive phenological network of the German Weather Service were used. About 1500 observations per year and species (Beech, Oak and Birch) were available evenly distributed all over Germany. Two filtering methods were tested to reduce the noisy raw data. The first method only keeps NDVI values which are classified as ‚ideal global quality' and applies on those a temporal moving window where values are removed which differ more than 20% of the mean. The second method uses an adaptation of the BISE (Best Index Slope Extraction) algorithm. Subsequently, three functions were fitted to the selected observations: a simple linear interpolation, a sigmoidal function and a double logistic sigmoidal function allowing to approximate two temporally separated green-up signals. The green-up date was then determined at halfway between minimum and maximum (linear interpolation) or at the inflexion point of the sigmoidal curve. A number of global threshold values (NDVI 0.4,0.5,0.6) and

A Model Assessment of Satellite Observed Trends in Polar Sea Ice Extents

NASA Technical Reports Server (NTRS)

Vinnikov, Konstantin Y.; Cavalieri, Donald J.; Parkinson, Claire L.

2005-01-01

For more than three decades now, satellite passive microwave observations have been used to monitor polar sea ice. Here we utilize sea ice extent trends determined from primarily satellite data for both the Northern and Southern Hemispheres for the period 1972(73)-2004 and compare them with results from simulations by eleven climate models. In the Northern Hemisphere, observations show a statistically significant decrease of sea ice extent and an acceleration of sea ice retreat during the past three decades. However, from the modeled natural variability of sea ice extents in control simulations, we conclude that the acceleration is not statistically significant and should not be extrapolated into the future. Observations and model simulations show that the time scale of climate variability in sea ice extent in the Southern Hemisphere is much larger than in the Northern Hemisphere and that the Southern Hemisphere sea ice extent trends are not statistically significant.

Surface topography estimated by inversion of satellite gravity gradiometry observations

NASA Astrophysics Data System (ADS)

Ramillien, Guillaume

2015-04-01

An integration of mass elements is presented for evaluating the six components of the 2-order gravity tensor (i.e., second derivatives of the Newtonian mass integral for the gravitational potential) created by an uneven sphere topography consisting of juxtaposed vertical prisms. The method is based on Legendre polynomial series with the originality of taking elastic compensation of the topography by the Earth's surface into account. The speed of computation of the polynomial series increases logically with the observing altitude from the source of anomaly. Such a forward modelling can be easily used for reduction of observed gravity gradient anomalies by the effects of any spherical interface of density. Moreover, an iterative least-square inversion of the observed gravity tensor values Γαβ is proposed to estimate a regional set of topographic heights. Several tests of recovery have been made by considering simulated gradiometry anomaly data, and for varying satellite altitudes and a priori levels of accuracy. In the case of GOCE-type gradiometry anomalies measured at an altitude of ~300 km, the search converges down to a stable and smooth topography after 20-30 iterations while the final r.m.s. error is ~100 m. The possibility of cumulating satellite information from different orbit geometries is also examined for improving the prediction.

SatelliteDL - An IDL Toolkit for the Analysis of Satellite Earth Observations - GOES, MODIS, VIIRS and CERES

NASA Astrophysics Data System (ADS)

Fillmore, D. W.; Galloy, M. D.; Kindig, D.

2013-12-01

SatelliteDL is an IDL toolkit for the analysis of satellite Earth observations from a diverse set of platforms and sensors. The design features an abstraction layer that allows for easy inclusion of new datasets in a modular way. The core function of the toolkit is the spatial and temporal alignment of satellite swath and geostationary data. IDL has a powerful suite of statistical and visualization tools that can be used in conjunction with SatelliteDL. Our overarching objective is to create utilities that automate the mundane aspects of satellite data analysis, are extensible and maintainable, and do not place limitations on the analysis itself. Toward this end we have constructed SatelliteDL to include (1) HTML and LaTeX API document generation, (2) a unit test framework, (3) automatic message and error logs, (4) HTML and LaTeX plot and table generation, and (5) several real world examples with bundled datasets available for download. For ease of use, datasets, variables and optional workflows may be specified in a flexible format configuration file. Configuration statements may specify, for example, a region and date range, and the creation of images, plots and statistical summary tables for a long list of variables. SatelliteDL enforces data provenance; all data should be traceable and reproducible. The output NetCDF file metadata holds a complete history of the original datasets and their transformations, and a method exists to reconstruct a configuration file from this information. Release 0.1.0 of SatelliteDL is anticipated for the 2013 Fall AGU conference. It will distribute with ingest methods for GOES, MODIS, VIIRS and CERES radiance data (L1) as well as select 2D atmosphere products (L2) such as aerosol and cloud (MODIS and VIIRS) and radiant flux (CERES). Future releases will provide ingest methods for ocean and land surface products, gridded and time averaged datasets (L3 Daily, Monthly and Yearly), and support for 3D products such as temperature and

Tropospheric Emission Spectrometer (TES) for the Earth Observing System (EOS) CHEM Satellite

NASA Technical Reports Server (NTRS)

Beer, R.; Glavich, T.; Rider, D.

2000-01-01

The Tropospheric Emission Spectrometer (TES) is an imaging infrared Fourier transform spectrometer scheduled to be launched into polar sun-synchronous orbit on the Earth Observing System (EOS) CHEM satellite in December 2002.

OWL-Net: A global network of robotic telescopes for satellite observation

NASA Astrophysics Data System (ADS)

Park, Jang-Hyun; Yim, Hong-Suh; Choi, Young-Jun; Jo, Jung Hyun; Moon, Hong-Kyu; Park, Young-Sik; Bae, Young-Ho; Park, Sun-Youp; Roh, Dong-Goo; Cho, Sungki; Choi, Eun-Jung; Kim, Myung-Jin; Choi, Jin

2018-07-01

The OWL-Net (Optical Wide-field patroL Network) is composed of 0.5-m wide-field optical telescopes spread over the globe (Mongolia, Morocco, Israel, South Korea, and USA). All the observing stations are identical, operated in a fully robotic manner, and controlled by the headquarters located in Daejeon, Korea. The main objective of the OWL-Net is to obtain the orbital information of Korean LEO and GEO satellites using purely optical means and to maintain their orbital elements. The aperture size of the mirror is 0.5 m in the Ritchey-Chretien configuration, and its field of view is 1.1 deg on the CCD sensor. The telescope is equipped with an electrically cooled 4 K CCD camera with a 9-μm pixel size, and its pixel scale is 1 arcsec/pixel. A chopper wheel with variable speed is adopted to obtain multiple points in a single shot. Each observatory is equipped with a heavy-duty environment monitoring system for robust robotic observation. The headquarters has components for status monitoring, scheduling, network operation, orbit calculation, and database management. The test-phase operation of the whole system began in early 2017, although test runs for individual sites began in 2015. Although the OWL-Net has 7 observation modes for artificial satellites and astronomical objects, we are concentrating on a few modes for LEO satellites and calibration during the early phase. Some early results and analysis for system performance will be presented, and their implications will be discussed.

Direct Radiative Effect of Aerosols Based on PARASOL and OMI Satellite Observations

NASA Technical Reports Server (NTRS)

Lacagnina, Carlo; Hasekamp, Otto P.; Torres, Omar

2017-01-01

Accurate portrayal of the aerosol characteristics is crucial to determine aerosol contribution to the Earth's radiation budget. We employ novel satellite retrievals to make a new measurement-based estimate of the shortwave direct radiative effect of aerosols (DREA), both over land and ocean. Global satellite measurements of aerosol optical depth, single-scattering albedo (SSA), and phase function from PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) are used in synergy with OMI (Ozone Monitoring Instrument) SSA. Aerosol information is combined with land-surface bidirectional reflectance distribution function and cloud characteristics from MODIS (Moderate Resolution Imaging Spectroradiometer) satellite products. Eventual gaps in observations are filled with the state-of-the-art global aerosol model ECHAM5-HAM2. It is found that our estimate of DREA is largely insensitive to model choice. Radiative transfer calculations show that DREA at top-of-atmosphere is -4.6 +/- 1.5 W/sq m for cloud-free and -2.1 +/- 0.7 W/sq m for all-sky conditions, during year 2006. These fluxes are consistent with, albeit generally less negative over ocean than, former assessments. Unlike previous studies, our estimate is constrained by retrievals of global coverage SSA, which may justify different DREA values. Remarkable consistency is found in comparison with DREA based on CERES (Clouds and the Earth's Radiant Energy System) and MODIS observations.

Satellite-borne study of seismic phenomena by low frequency magnetic field observations

NASA Astrophysics Data System (ADS)

Schwingenschuh, Konrad; Magnes, Werner; Xuhui, Shen; Wang, Jindong; Pollinger, Andreas; Hagen, Christian; Prattes, Gustav; Eichelberger, Hans-Ulrich; Wolbang, Daniel; Boudjada, Mohammed Y.; Besser, Bruno P.; Rozhnoi, Alexander A.; Zhang, Tielong

2015-04-01

A combined scalar-vector magnetic field experiment will be flown on the upcoming CSES mission (China Seismo-Electromagnetic Satellite). Magnetic field data from DC to 30 Hz will be measured with an accuracy of about 10 pT. A fluxgate instrument will provide the 3 magnetic field components and a new type of an optically pumped magnetometer [see Pollinger, 2010] will measure the magnitude of the ambient magnetic field. The satellite will operate in a Sun synchronous polar orbit at an altitude of about 500 km and with an inclination of 97°. We present a model of magnetic field fluctuations in the upper ionosphere based on previous satellite observations and on a model of the lithospheric-atmospheric-ionospheric coupling. Pollinger et al., CDSM-a new scalar magnetometer, EGU General Assembly 2010

Use of Satellite Observations for Long-Term Exposure Assessment of Global Concentrations of Fine Particulate Matter

PubMed Central

Martin, Randall V.; Brauer, Michael; Boys, Brian L.

2014-01-01

Background: More than a decade of satellite observations offers global information about the trend and magnitude of human exposure to fine particulate matter (PM2.5). Objective: In this study, we developed improved global exposure estimates of ambient PM2.5 mass and trend using PM2.5 concentrations inferred from multiple satellite instruments. Methods: We combined three satellite-derived PM2.5 sources to produce global PM2.5 estimates at about 10 km × 10 km from 1998 through 2012. For each source, we related total column retrievals of aerosol optical depth to near-ground PM2.5 using the GEOS–Chem chemical transport model to represent local aerosol optical properties and vertical profiles. We collected 210 global ground-based PM2.5 observations from the literature to evaluate our satellite-based estimates with values measured in areas other than North America and Europe. Results: We estimated that global population-weighted ambient PM2.5 concentrations increased 0.55 μg/m3/year (95% CI: 0.43, 0.67) (2.1%/year; 95% CI: 1.6, 2.6) from 1998 through 2012. Increasing PM2.5 in some developing regions drove this global change, despite decreasing PM2.5 in some developed regions. The estimated proportion of the population of East Asia living above the World Health Organization (WHO) Interim Target-1 of 35 μg/m3 increased from 51% in 1998–2000 to 70% in 2010–2012. In contrast, the North American proportion above the WHO Air Quality Guideline of 10 μg/m3 fell from 62% in 1998–2000 to 19% in 2010–2012. We found significant agreement between satellite-derived estimates and ground-based measurements outside North America and Europe (r = 0.81; n = 210; slope = 0.68). The low bias in satellite-derived estimates suggests that true global concentrations could be even greater. Conclusions: Satellite observations provide insight into global long-term changes in ambient PM2.5 concentrations. Satellite-derived estimates and ground-based PM2.5 observations from this study

Satellite Analyses of Cirrus Cloud Properties During the FIRE Phase 2 Cirrus Intensive Field Observations over Kansas

NASA Technical Reports Server (NTRS)

Minnis, Patrick; Young, David F.; Heck, Patrick W.; Liou, Kuo-Nan; Takano, Yoshihide

1992-01-01

The First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE) Phase II Intensive Field Observations (IFO) were taken over southeastern Kansas between November 13 and December 7,1991, to determine cirrus cloud properties. The observations include in situ microphysical data; surface, aircraft, and satellite remote sensing; and measurements of divergence over meso- and smaller-scale areas using wind profilers. Satellite remote sensing of cloud characteristics is an essential aspect for understanding and predicting the role of clouds in climate variations. The objectives of the satellite cloud analysis during FIRE are to validate cloud property retrievals, develop advanced methods for extracting cloud information from satellite-measured radiances, and provide multiscale cloud data for cloud process studies and for verification of cloud generation models. This paper presents the initial results of cloud property analyses during FIRE-II using Geostationary Operational Environmental Satellite (GOES) data and NOAA Advanced Very High Resolution Radiometer (AVHRR) radiances.

A catalogue of ground-based astrometric observations of the Martian satellites, 1877-1982

NASA Astrophysics Data System (ADS)

Morley, T. A.

1989-02-01

A catalog of 5767 ground-based astrometric observations of the Martian satellites, Phobos and Deimos, has been compiled. The position measurements comprise: 2497 of Phobos relative to Mars 3116 of Deimos relative to Mars and 154 of Deimos relative to Phobos. The data have been extracted from both published and unpublished sources and have been tabulated in a consistent format. All the observation times have been converted to the same time system, UTC. The catalog contains accuracy figures which can be used to differentially weigh the data when they are used for orbit determination purposes. Bad quality measurements have been identified and some obvious blunders have been corrected. The catalog is the official source of ground-based observations to be used for improving the satellite ephemerides in support of the Soviet Phobos mission.

Bio-Optical Data Assimilation With Observational Error Covariance Derived From an Ensemble of Satellite Images

NASA Astrophysics Data System (ADS)

Shulman, Igor; Gould, Richard W.; Frolov, Sergey; McCarthy, Sean; Penta, Brad; Anderson, Stephanie; Sakalaukus, Peter

2018-03-01

An ensemble-based approach to specify observational error covariance in the data assimilation of satellite bio-optical properties is proposed. The observational error covariance is derived from statistical properties of the generated ensemble of satellite MODIS-Aqua chlorophyll (Chl) images. The proposed observational error covariance is used in the Optimal Interpolation scheme for the assimilation of MODIS-Aqua Chl observations. The forecast error covariance is specified in the subspace of the multivariate (bio-optical, physical) empirical orthogonal functions (EOFs) estimated from a month-long model run. The assimilation of surface MODIS-Aqua Chl improved surface and subsurface model Chl predictions. Comparisons with surface and subsurface water samples demonstrate that data assimilation run with the proposed observational error covariance has higher RMSE than the data assimilation run with "optimistic" assumption about observational errors (10% of the ensemble mean), but has smaller or comparable RMSE than data assimilation run with an assumption that observational errors equal to 35% of the ensemble mean (the target error for satellite data product for chlorophyll). Also, with the assimilation of the MODIS-Aqua Chl data, the RMSE between observed and model-predicted fractions of diatoms to the total phytoplankton is reduced by a factor of two in comparison to the nonassimilative run.

Quasiperiodic modulations of energetic electron fluxes in the ULF range observed by the ERG satellite

NASA Astrophysics Data System (ADS)

Teramoto, M.; Hori, T.; Kurita, S.; Yoshizumi, M.; Saito, S.; Higashio, N.; Mitani, T.; Matsuoka, A.; Park, I.; Takashima, T.; Nomura, R.; Nose, M.; Fujimoto, A.; Tanaka, Y.; Shinohara, M.; Shinohara, I.

2017-12-01

Exploration of energization and Radiation in Geospace (ERG) satellite was successfully launched on December 20, 2016. The Extremely High-Energy Electron Experiment (XEP) and High-Energy Electron Experiments (HEP-L and HEP-H) are carried by the ERG satellite to observe energetic electrons. These instruments frequently observed quasiperiodic modulations of energetic electron fluxes with period of 100-600 sec. Continuous flux modulations with the period of 600 s appeared in the 700keV-3.6MeV energy range during the period 0920UT-1120UT on March 31, 2017 when the ERG satellite was located at L 5.5-6.1 and MLT 3-4 h. We compare these flux modulations with the magnetic field observed by the Magnetic Field Experiment (MGF) on the ERG satellite. It is found that these flux modulations are not accompanied by corresponding magnetic signatures. It indicates that these quasiperiodic flux modulations are not caused by drift-resonant interactions between ULF waves and energetic electrons, at least locally. In this study, we will show several events and discuss possible mechanism for quasiperiodic flux modulations of energetic electrons on XEP and HEP.

Periodic magnetopause oscillations observed with the GOES satellites on March 24, 1991

NASA Technical Reports Server (NTRS)

Cahill, L. J., Jr.; Winckler, J. R.

1992-01-01

The GOES 6 and 7 satellites were in the dayside magnetosphere late on March 24, 1991, when the magnetopause moved in to geosynchronous orbit. Observations on GOES 6 near 1030 local time (LT) indicated six inward and outward periodic movements of the magnetopause past the satellite over a 30-min interval. Later the magnetopause moved farther in, placing GOES 6 (1100 LT) in the magnetosheath and then moving in past GOES 7, near 1245 LT. The periodic oscillations of the magnetopause at GOES 6 suggest surface waves propagating toward the dawn flank of the magnetopause.

Upper-Tropospheric Winds Derived from Geostationary Satellite Water Vapor Observations

NASA Technical Reports Server (NTRS)

Velden, Christopher S.; Hayden, Christopher M.; Nieman, Steven J.; Menzel, W. Paul; Wanzong, Steven; Goerss, James S.

1997-01-01

The coverage and quality of remotely sensed upper-tropospheric moisture parameters have improved considerably with the deployment of a new generation of operational geostationary meteorological satellites: GOES-8/9 and GMS-5. The GOES-8/9 water vapor imaging capabilities have increased as a result of improved radiometric sensitivity and higher spatial resolution. The addition of a water vapor sensing channel on the latest GMS permits nearly global viewing of upper-tropospheric water vapor (when joined with GOES and Meteosat) and enhances the commonality of geostationary meteorological satellite observing capabilities. Upper-tropospheric motions derived from sequential water vapor imagery provided by these satellites can be objectively extracted by automated techniques. Wind fields can be deduced in both cloudy and cloud-free environments. In addition to the spatially coherent nature of these vector fields, the GOES-8/9 multispectral water vapor sensing capabilities allow for determination of wind fields over multiple tropospheric layers in cloud-free environments. This article provides an update on the latest efforts to extract water vapor motion displacements over meteorological scales ranging from subsynoptic to global. The potential applications of these data to impact operations, numerical assimilation and prediction, and research studies are discussed.

The survey on data format of Earth observation satellite data at JAXA.

NASA Astrophysics Data System (ADS)

Matsunaga, M.; Ikehata, Y.

2017-12-01

JAXA's earth observation satellite data are distributed by a portal web site for search and deliver called "G-Portal". Users can download the satellite data of GPM, TRMM, Aqua, ADEOS-II, ALOS (search only), ALOS-2 (search only), MOS-1, MOS-1b, ERS-1 and JERS-1 from G-Portal. However, these data formats are different by each satellite like HDF4, HDF5, NetCDF4, CEOS, etc., and which formats are not familiar to new data users. Although the HDF type self-describing format is very convenient and useful for big dataset information, old-type format product is not readable by open GIS tool nor apply OGC standard. Recently, the satellite data are widely used to be applied to the various needs such as disaster, earth resources, monitoring the global environment, Geographic Information System(GIS) and so on. In order to remove a barrier of using Earth Satellite data for new community users, JAXA has been providing the format-converted product like GeoTIFF or KMZ. In addition, JAXA provides format conversion tool itself. We investigate the trend of data format for data archive, data dissemination and data utilization, then we study how to improve the current product format for various application field users and make a recommendation for new product.

KAGLVis - On-line 3D Visualisation of Earth-observing-satellite Data

NASA Astrophysics Data System (ADS)

Szuba, Marek; Ameri, Parinaz; Grabowski, Udo; Maatouki, Ahmad; Meyer, Jörg

2015-04-01

One of the goals of the Large-Scale Data Management and Analysis project is to provide a high-performance framework facilitating management of data acquired by Earth-observing satellites such as Envisat. On the client-facing facet of this framework, we strive to provide visualisation and basic analysis tool which could be used by scientists with minimal to no knowledge of the underlying infrastructure. Our tool, KAGLVis, is a JavaScript client-server Web application which leverages modern Web technologies to provide three-dimensional visualisation of satellite observables on a wide range of client systems. It takes advantage of the WebGL API to employ locally available GPU power for 3D rendering; this approach has been demonstrated to perform well even on relatively weak hardware such as integrated graphics chipsets found in modern laptop computers and with some user-interface tuning could even be usable on embedded devices such as smartphones or tablets. Data is fetched from the database back-end using a ReST API and cached locally, both in memory and using HTML5 Web Storage, to minimise network use. Computations, calculation of cloud altitude from cloud-index measurements for instance, can depending on configuration be performed on either the client or the server side. Keywords: satellite data, Envisat, visualisation, 3D graphics, Web application, WebGL, MEAN stack.

Observing System Simulations for Small Satellite Formations Estimating Bidirectional Reflectance

NASA Technical Reports Server (NTRS)

Nag, Sreeja; Gatebe, Charles K.; de Weck, Olivier

2015-01-01

The bidirectional reflectance distribution function (BRDF) gives the reflectance of a target as a function of illumination geometry and viewing geometry, hence carries information about the anisotropy of the surface. BRDF is needed in remote sensing for the correction of view and illumination angle effects (for example in image standardization and mosaicing), for deriving albedo, for land cover classification, for cloud detection, for atmospheric correction, and other applications. However, current spaceborne instruments provide sparse angular sampling of BRDF and airborne instruments are limited in the spatial and temporal coverage. To fill the gaps in angular coverage within spatial, spectral and temporal requirements, we propose a new measurement technique: Use of small satellites in formation flight, each satellite with a VNIR (visible and near infrared) imaging spectrometer, to make multi-spectral, near-simultaneous measurements of every ground spot in the swath at multiple angles. This paper describes an observing system simulation experiment (OSSE) to evaluate the proposed concept and select the optimal formation architecture that minimizes BRDF uncertainties. The variables of the OSSE are identified; number of satellites, measurement spread in the view zenith and relative azimuth with respect to solar plane, solar zenith angle, BRDF models and wavelength of reflection. Analyzing the sensitivity of BRDF estimation errors to the variables allow simplification of the OSSE, to enable its use to rapidly evaluate formation architectures. A 6-satellite formation is shown to produce lower BRDF estimation errors, purely in terms of angular sampling as evaluated by the OSSE, than a single spacecraft with 9 forward-aft sensors. We demonstrate the ability to use OSSEs to design small satellite formations as complements to flagship mission data. The formations can fill angular sampling gaps and enable better BRDF products than currently possible.

Observing system simulations for small satellite formations estimating bidirectional reflectance

NASA Astrophysics Data System (ADS)

Nag, Sreeja; Gatebe, Charles K.; Weck, Olivier de

2015-12-01

The bidirectional reflectance distribution function (BRDF) gives the reflectance of a target as a function of illumination geometry and viewing geometry, hence carries information about the anisotropy of the surface. BRDF is needed in remote sensing for the correction of view and illumination angle effects (for example in image standardization and mosaicing), for deriving albedo, for land cover classification, for cloud detection, for atmospheric correction, and other applications. However, current spaceborne instruments provide sparse angular sampling of BRDF and airborne instruments are limited in the spatial and temporal coverage. To fill the gaps in angular coverage within spatial, spectral and temporal requirements, we propose a new measurement technique: use of small satellites in formation flight, each satellite with a VNIR (visible and near infrared) imaging spectrometer, to make multi-spectral, near-simultaneous measurements of every ground spot in the swath at multiple angles. This paper describes an observing system simulation experiment (OSSE) to evaluate the proposed concept and select the optimal formation architecture that minimizes BRDF uncertainties. The variables of the OSSE are identified; number of satellites, measurement spread in the view zenith and relative azimuth with respect to solar plane, solar zenith angle, BRDF models and wavelength of reflection. Analyzing the sensitivity of BRDF estimation errors to the variables allow simplification of the OSSE, to enable its use to rapidly evaluate formation architectures. A 6-satellite formation is shown to produce lower BRDF estimation errors, purely in terms of angular sampling as evaluated by the OSSE, than a single spacecraft with 9 forward-aft sensors. We demonstrate the ability to use OSSEs to design small satellite formations as complements to flagship mission data. The formations can fill angular sampling gaps and enable better BRDF products than currently possible.

Airborne Observations and Satellite Validation: INTEX-A Experience and INTEX-B Plans

NASA Technical Reports Server (NTRS)

Crawford, James H.; Singh, Hanwant B.; Brune, William H.; Jacob, Daniel J.

2005-01-01

Intercontinental Chemical Transport Experiment (INTEX; http://cloudl.arc.nasa.gov) is an ongoing two-phase integrated atmospheric field experiment being performed over North America (NA). Its first phase (INTEX-A) was performed in the summer of 2004 and the second phase (INTEX-B) is planned for the early spring of 2006. The main goal of INTEX-NA is to understand the transport and transformation of gases and aerosols on transcontinental/intercontinental scales and to assess their impact on air quality and climate. Central to achieving this goal is the need to relate space-based observations with those from airborne and surface platforms. During INTEX-A, NASA s DC-8 was joined by some dozen other aircraft from a large number of European and North American partners to focus on the outflow of pollution from NA to the Atlantic. Several instances of Asian pollution over NA were also encountered. INTEX-A flight planning extensively relied on satellite observations and in turn Satellite validation (Terra, Aqua, and Envisat) was given high priority. Over 20 validation profiles were successfully carried out. DC-8 sampling of smoke from Alaskan fires and formaldehyde over forested regions, and simultaneous satellite observations of these provided excellent opportunities for the interplay of these platforms. The planning for INTEX-5 is currently underway, and a vast majority of "standard" and "research" products to be retrieved from Aura instruments will be measured during INTEX-B throughout the troposphere. INTEX-B will focus on the inflow of pollution from Asia to North America and validation of satellite observations with emphasis on Aura. Several national and international partners are expected to coordinate activities with INTEX-B, and we expect its scope to expand in the coming months. An important new development involves partnership with an NSF-sponsored campaign called MIRAGE (Megacity Impacts on Regional and Global Environments- Mexico City Pollution Outflow Field

Simultaneous all-sky and multi-satellite observations of auroral breakup and magnetic reconnection

NASA Astrophysics Data System (ADS)

Kawashima, T.; Ieda, A.; Machida, S.; Nishimura, Y.; Miura, T.

2017-12-01

A substorm is a large-scale disturbance including auroral breakup in the ionosphere and magnetic reconnection in the magnetotail. Two predominant models of the substorm time history have been proposed: the near-Earth neutral line (NENL) model and the current disruption model. The former is of outside-in type with tailward propagation of the disturbance, whereas the latter is of inside-out type with earthward propagation of the disturbance. To determine such time histories of such substorms using aurora all-sky and magnetotail multi-satellite observations, the National Aeronautics and Space Administration (NASA) is conducting a mission named the "Time History of Events and Macroscale Interactions during Substorms (THEMIS)". The time history of a substorm is expected to be best clarified when satellites are aligned along the tail axis. A substorm occurred under such a satellite distribution on 0743:42 UT February 27, 2009, and we investigated the auroral breakup and fast plasma flows produced by the magnetic reconnection in this substorm. The THEMIS satellites observed that a northward magnetic field variation propagated earthward. Because this earthward propagation is consistent with the NENL model, observation of a substorm onset after the magnetic reconnection was expected. However, the substorm onset was observed in the all-sky images before the magnetic reconnection, as noted in a previous study. In this study, we report that another earthward fast plasma flow occurred before the substorm onset, indicating that another magnetic reconnection occurred before the substorm onset. In addition, we confirm that the above mentioned post-onset magnetic reconnection occurred simultaneously with auroral poleward expansion, within a 1-min period. These results support the NENL model and further suggest that the two-step development of magnetic reconnection is a key component of the substorm time history.

Navy Prototype Optical Interferometer observations of geosynchronous satellites.

PubMed

Hindsley, Robert B; Armstrong, J Thomas; Schmitt, Henrique R; Andrews, Jonathan R; Restaino, Sergio R; Wilcox, Christopher C; Vrba, Frederick J; Benson, James A; DiVittorio, Michael E; Hutter, Donald J; Shankland, Paul D; Gregory, Steven A

2011-06-10

Using a 15.9  m baseline at the Navy Prototype Optical Interferometer (NPOI), we have successfully detected interferometric fringes in observations of the geosynchronous satellite (geosat) DirecTV-9S while it glinted on two nights in March 2009. The fringe visibilities can be fitted by a model consisting of two components, one resolved (≳3.7  m) and one unresolved (∼1.1  m). Both the length of the glint and the specular albedos are consistent with the notion that the glinting surfaces are not completely flat and scatter reflected sunlight into an opening angle of roughly 15°. Enhancements to the NPOI that would improve geosat observations include adding an infrared capability, which could extend the glint season, and adding larger, adaptive-optics equipped telescopes. Future work may test the feasibility of observing geosats with aperture-masked large telescopes and of developing an array of six to nine elements.

Subtropical Gyre Variability Observed by Ocean Color Satellites

NASA Technical Reports Server (NTRS)

McClain, Charles R.; Signorini, Sergio R.; Christian, James R.

2002-01-01

The subtropical gyres of the world are extensive, coherent regions that occupy about 40% of the surface of the earth. Once thought to be homogeneous and static habitats, there is increasing evidence that mid-latitude gyres exhibit substantial physical and biological variability on a variety of time scales. While biological productivity within these oligotrophic regions may be relatively small, their immense size makes their total contribution significant. Global distributions of dynamic height derived from satellite altimeter data, and chlorophyll concentration derived from satellite ocean color data, show that the dynamic center of the gyres, the region of maximum dynamic height where the thermocline is deepest, does not coincide with the region of minimum chlorophyll concentration. The physical and biological processes by which this distribution of ocean properties is maintained, and the spatial and temporal scales of variability associated with these processes, are analyzed using global surface chlorophyll-a concentrations, sea surface height, sea surface temperature and surface winds from operational satellite and meteorological sources, and hydrographic data from climatologies and individual surveys. Seasonal and interannual variability in the areal extent of the subtropical gyres are examined using 8 months (November 1996 - June 1997) of OCTS and nearly 5 years (September 1997 - June 02) of SeaWiFS ocean color data and are interpreted in the context of climate variability and measured changes in other ocean properties (i.e., wind forcing, surface currents, Ekman pumping, and vertical mixing). The North Pacific and North Atlantic gyres are observed to be shrinking over this period, while the South Pacific, South Atlantic, and South Indian Ocean gyres appear to be expanding.

Observations on Complexity and Costs for Over Three Decades of Communications Satellites

NASA Astrophysics Data System (ADS)

Bearden, David A.

2002-01-01

This paper takes an objective look at approximately thirty communications satellites built over three decades using a complexity index as an economic model. The complexity index is derived from a number of technical parameters including dry mass, end-of-life- power, payload type, communication bands, spacecraft lifetime, and attitude control approach. Complexity is then plotted versus total satellite cost and development time (defined as contract start to first launch). A comparison of the relative cost and development time for various classes of communications satellites and conclusions regarding dependence on system complexity are presented. Observations regarding inherent differences between commercially acquired systems and those procured by government organizations are also presented. A process is described where a new communications system in the formative stage may be compared against similarly "complex" missions of the recent past to balance risk within allotted time and funds. 1

Observing convection with satellite, radar, and lightning measurements

NASA Astrophysics Data System (ADS)

Hamann, Ulrich; Nisi, Luca; Clementi, Lorenzo; Ventura, Jordi Figueras i.; Gabella, Marco; Hering, Alessandro M.; Sideris, Ioannis; Trefalt, Simona; Germann, Urs

2015-04-01

Heavy precipitation, hail, and wind gusts are the fundamental meteorological hazards associated with strong convection and thunderstorms. The thread is particularly severe in mountainous areas, e.g. it is estimated that on average between 50% and 80% of all weather-related damage in Switzerland is caused by strong thunderstorms (Hilker et al., 2010). Intense atmospheric convection is governed by processes that range from the synoptic to the microphysical scale and are considered to be one of the most challenging and difficult weather phenomena to predict. Even though numerical weather prediction models have some skills to predict convection, in general the exact location of the convective initialization and its propagation cannot be forecasted by these models with sufficient precision. Hence, there is a strong interest to improve the short-term forecast by using statistical, object oriented and/or heuristic nowcasting methods. MeteoSwiss has developed several operational nowcasting systems for this purpose such as TRT (Hering, 2008) and COALITION (Nisi, 2014). In this contribution we analyze the typical development of convection using measurements of the Swiss C-band Dual Polarization Doppler weather radar network, the MSG SEVIRI satellite, and the Météorage lighting network. The observations are complemented with the analysis and forecasts of the COSMO model. Special attention is given to the typical evolutionary stages like the pre-convective environment, convective initiation, cloud top glaciation, start, maximum, and end of precipitation and lightning activity. The pre-convective environment is examined using instability indices derived from SEVIRI observations and the COSMO forecasts. During the early development satellite observations are used to observe the rise of the cloud top, the growth of the cloud droplet or crystals, and the glaciation of the cloud top. SEVIRI brightness temperatures, channel differences, and temporal trends as suggested by

Utility of Satellite Magnetic Observations for Estimating Near-Surface Magnetic Anomalies

NASA Technical Reports Server (NTRS)

Kim, Hyung Rae; vonFrese, Ralph R. B.; Taylor, Patrick T.; Kim, Jeong Woo; Park, Chan Hong

2003-01-01

Regional to continental scale magnetic anomaly maps are becoming increasingly available from airborne, shipborne, and terrestrial surveys. Satellite data are commonly considered to fill the coverage gaps in regional compilations of these near-surface surveys. For the near-surface Antarctic magnetic anomaly map being produced by the Antarctic Digital Magnetic Anomaly Project (ADMAP), we show that near-surface magnetic anomaly estimation is greatly enhanced by the joint inversion of the near-surface data with the satellite observations relative to the conventional technique such as minimum curvature. Orsted observations are especially advantageous relative to the Magsat data that have order-of-magnitude greater measurement errors, albeit at much lower orbital altitudes. CHAMP is observing the geomagnetic field with the same measurement accuracy as the Orsted mission, but at the lower orbital altitudes covered by Magsat. Hence, additional significant improvement in predicting near-surface magnetic anomalies can result as these CHAMP data are available. Our analysis also suggests that considerable new insights on the magnetic properties of the lithosphere may be revealed by a further order-of-magnitude improvement in the accuracy of the magnetometer measurements at minimum orbital altitude.

Validation of NH3 satellite observations by ground-based FTIR measurements

NASA Astrophysics Data System (ADS)

Dammers, Enrico; Palm, Mathias; Van Damme, Martin; Shephard, Mark; Cady-Pereira, Karen; Capps, Shannon; Clarisse, Lieven; Coheur, Pierre; Erisman, Jan Willem

2016-04-01

Global emissions of reactive nitrogen have been increasing to an unprecedented level due to human activities and are estimated to be a factor four larger than pre-industrial levels. Concentration levels of NOx are declining, but ammonia (NH3) levels are increasing around the globe. While NH3 at its current concentrations poses significant threats to the environment and human health, relatively little is known about the total budget and global distribution. Surface observations are sparse and mainly available for north-western Europe, the United States and China and are limited by the high costs and poor temporal and spatial resolution. Since the lifetime of atmospheric NH3 is short, on the order of hours to a few days, due to efficient deposition and fast conversion to particulate matter, the existing surface measurements are not sufficient to estimate global concentrations. Advanced space-based IR-sounders such as the Tropospheric Emission Spectrometer (TES), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) enable global observations of atmospheric NH3 that help overcome some of the limitations of surface observations. However, the satellite NH3 retrievals are complex requiring extensive validation. Presently there have only been a few dedicated satellite NH3 validation campaigns performed with limited spatial, vertical or temporal coverage. Recently a retrieval methodology was developed for ground-based Fourier Transform Infrared Spectroscopy (FTIR) instruments to obtain vertical concentration profiles of NH3. Here we show the applicability of retrieved columns from nine globally distributed stations with a range of NH3 pollution levels to validate satellite NH3 products.

The role of ecosystem memory in predicting inter-annual variations of the tropical carbon balance.

NASA Astrophysics Data System (ADS)

Bloom, A. A.; Liu, J.; Bowman, K. W.; Konings, A. G.; Saatchi, S.; Worden, J. R.; Worden, H. M.; Jiang, Z.; Parazoo, N.; Williams, M. D.; Schimel, D.

2017-12-01

Understanding the trajectory of the tropical carbon balance remains challenging, in part due to large uncertainties in the integrated response of carbon cycle processes to climate variability. Satellite observations atmospheric CO2 from GOSAT and OCO-2, together with ancillary satellite measurements, provide crucial constraints on continental-scale terrestrial carbon fluxes. However, an integrated understanding of both climate forcings and legacy effects (or "ecosystem memory") on the terrestrial carbon balance is ultimately needed to reduce uncertainty on its future trajectory. Here we use the CARbon DAta-MOdel fraMework (CARDAMOM) diagnostic model-data fusion approach - constrained by an array of C cycle satellite surface observations, including MODIS leaf area, biomass, GOSAT solar-induced fluorescence, as well as "top-down" atmospheric inversion estimates of CO2 and CO surface fluxes from the NASA Carbon Monitoring System Flux (CMS-Flux) - to constrain and predict spatially-explicit tropical carbon state variables during 2010-2015. We find that the combined assimilation of land surface and atmospheric datasets places key constraints on the temperature sensitivity and first order carbon-water feedbacks throughout the tropics and combustion factors within biomass burning regions. By varying the duration of the assimilation period, we find that the prediction skill on inter-annual net biospheric exchange is primarily limited by record length rather than model structure and process representation. We show that across all tropical biomes, quantitative knowledge of memory effects - which account for 30-50% of interannual variations across the tropics - is critical for understanding and ultimately predicting the inter-annual tropical carbon balance.

Advances in Assimilation of Satellite-Based Passive Microwave Observations for Soil-Moisture Estimation

NASA Technical Reports Server (NTRS)

De Lannoy, Gabrielle J. M.; Pauwels, Valentijn; Reichle, Rolf H.; Draper, Clara; Koster, Randy; Liu, Qing

2012-01-01

Satellite-based microwave measurements have long shown potential to provide global information about soil moisture. The European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS, [1]) mission as well as the future National Aeronautics and Space Administration (NASA) Soil Moisture Active and Passive (SMAP, [2]) mission measure passive microwave emission at L-band frequencies, at a relatively coarse (40 km) spatial resolution. In addition, SMAP will measure active microwave signals at a higher spatial resolution (3 km). These new L-band missions have a greater sensing depth (of -5cm) compared with past and present C- and X-band microwave sensors. ESA currently also disseminates retrievals of SMOS surface soil moisture that are derived from SMOS brightness temperature observations and ancillary data. In this research, we address two major challenges with the assimilation of recent/future satellite-based microwave measurements: (i) assimilation of soil moisture retrievals versus brightness temperatures for surface and root-zone soil moisture estimation and (ii) scale-mismatches between satellite observations, models and in situ validation data.

A Comparison of Techniques for Scheduling Earth-Observing Satellites

NASA Technical Reports Server (NTRS)

Globus, Al; Crawford, James; Lohn, Jason; Pryor, Anna

2004-01-01

Scheduling observations by coordinated fleets of Earth Observing Satellites (EOS) involves large search spaces, complex constraints and poorly understood bottlenecks, conditions where evolutionary and related algorithms are often effective. However, there are many such algorithms and the best one to use is not clear. Here we compare multiple variants of the genetic algorithm: stochastic hill climbing, simulated annealing, squeaky wheel optimization and iterated sampling on ten realistically-sized EOS scheduling problems. Schedules are represented by a permutation (non-temperal ordering) of the observation requests. A simple deterministic scheduler assigns times and resources to each observation request in the order indicated by the permutation, discarding those that violate the constraints created by previously scheduled observations. Simulated annealing performs best. Random mutation outperform a more 'intelligent' mutator. Furthermore, the best mutator, by a small margin, was a novel approach we call temperature dependent random sampling that makes large changes in the early stages of evolution and smaller changes towards the end of search.