Grid systems for Earth radiation budget experiment applications

NASA Technical Reports Server (NTRS)

Brooks, D. R.

1981-01-01

Spatial coordinate transformations are developed for several global grid systems of interest to the Earth Radiation Budget Experiment. The grid boxes are defined in terms of a regional identifier and longitude-latitude indexes. The transformations associate longitude with a particular grid box. The reverse transformations identify the center location of a given grid box. Transformations are given to relate the rotating (Earth-based) grid systems to solar position expressed in an inertial (nonrotating) coordinate system. The FORTRAN implementations of the transformations are given, along with sample input and output.

Nimbus 7 earth radiation budget wide field of view climate data set improvement. II - Deconvolution of earth radiation budget products and consideration of 1982-1983 El Nino event

NASA Technical Reports Server (NTRS)

Ardanuy, Phillip E.; Hucek, Richard R.; Groveman, Brian S.; Kyle, H. Lee

1987-01-01

A deconvolution technique is employed that permits recovery of daily averaged earth radiation budget (ERB) parameters at the top of the atmosphere from a set of the Nimbus 7 ERB wide field of view (WFOV) measurements. Improvements in both the spatial resolution of the resultant fields and in the fidelity of the time averages is obtained. The algorithm is evaluated on a set of months during the period 1980-1983. The albedo, outgoing long-wave radiation, and net radiation parameters are analyzed. The amplitude and phase of the quasi-stationary patterns that appear in the spatially deconvolved fields describe the radiation budget components for 'normal' as well as the El Nino/Southern Oscillation (ENSO) episode years. They delineate the seasonal development of large-scale features inherent in the earth's radiation budget as well as the natural variability of interannual differences. These features are underscored by the powerful emergence of the 1982-1983 ENSO event in the fields displayed. The conclusion is that with this type of resolution enhancement, WFOV radiometers provide a useful tool for the observation of the contemporary climate and its variability.

A radiometric model of an earth radiation budget radiometer optical system with diffuse-specular surfaces

NASA Technical Reports Server (NTRS)

Luther, M. R.

1981-01-01

The Earth Radiation Budget Experiment (ERBE) is to fly on NASA's Earth Radiation Budget Satellite (ERBS) and on NOAA F and NOAA G. Large spatial scale earth energy budget data will be derived primarily from measurements made by the ERBE nonscanning instrument (ERBE-NS). A description is given of a mathematical model capable of simulating the radiometric response of any of the ERBE-NS earth viewing channels. The model uses a Monte Carlo method to accurately account for directional distributions of emission and reflection from optical surfaces which are neither strictly diffuse nor strictly specular. The model computes radiation exchange factors among optical system components, and determines the distribution in the optical system of energy from an outside source. Attention is also given to an approach for implementing the model and results obtained from the implementation.

The geostationary Earth radiation budget (GERB) instrument on EUMETSAT's MSG satellite

NASA Astrophysics Data System (ADS)

Sandford, M. C. W.; Allan, P. M.; Caldwell, M. E.; Delderfield, J.; Oliver, M. B.; Sawyer, E.; Harries, J. E.; Ashmall, J.; Brindley, H.; Kellock, S.; Mossavati, R.; Wrigley, R.; Llewellyn-Jones, D.; Blake, O.; Butcher, G.; Cole, R.; Nelms, N.; DeWitte, S.; Gloesener, P.; Fabbrizzi, F.

2003-12-01

Geostationary Earth radiation budget (GERB) is an Announcement of Opportunity Instrument for EUMETSAT's Meteosat Second Generation (MSG) satellite. GERB will make accurate measurements of the Earth Radiation Budget from geostationary orbit, provide an absolute reference calibration for LEO Earth radiation budget instruments and allow studies of the energetics of atmospheric processes. By operating from geostationary orbit, measurements may be made many times a day, thereby providing essentially perfect diurnal sampling of the radiation balance between reflected and emitted radiance for that area of the globe within the field of view. GERB will thus complement other instruments which operate in low orbit and give complete global coverage, but with poor and biased time resolution. GERB measures infrared radiation in two wavelength bands: 0.32-4.0 and 0.32- 30 μm, with a pixel element size of 44 km at sub-satellite point. This paper gives an overview of the project and concentrates on the design and development of the instrument and ground testing and calibration, and lessons learnt from a short time scale low-budget project. The instrument was delivered for integration on the MSG platform in April 1999 ready for the proposed launch in October 2000, which has now been delayed probably to early 2002. The ground segment is being undertaken by RAL and RMIB and produces near real-time data for meteorological applications in conjunction with the main MSG imager—SEVERI. Climate research and other applications which are being developed under a EU Framework IV pilot project will be served by fully processed data. Because of the relevance of the observations to climate change, it is planned to maintain an operating instrument in orbit for at least 3.5 years. Two further GERB instruments are being built for subsequent launches of MSG.

On-orbit characterizations of Earth Radiation Budget Experiment broadband shortwave active cavity radiometer sensor responses

NASA Astrophysics Data System (ADS)

Lee, Robert B., III; Wilson, Robert S.; Smith, G. Louis; Bush, Kathryn A.; Thomas, Susan; Pandey, Dhirendra K.; Paden, Jack

2004-12-01

The NASA Earth Radiation Budget Experiment (ERBE) missions were designed to monitor long-term changes in the earth radiation budget components which may cause climate changes. During the October 1984 through September 2004 period, the NASA Earth Radiation Budget Satellite (ERBS)/ERBE nonscanning active cavity radiometers (ACR) were used to monitor long-term changes in the earth radiation budget components of the incoming total solar irradiance (TSI), earth-reflected TSI, and earth-emitted outgoing longwave radiation (OLR). The earth-reflected total solar irradiances were measured using broadband shortwave fused, waterless quartz (Suprasil) filters and ACR"s that were covered with a black paint absorbing surface. Using on-board calibration systems, 1984 through 1999, long-term ERBS/ERBE ACR sensor response changes were determined from direct observations of the incoming TSI in the 0.2-5 micrometer shortwave broadband spectral region. During the October 1984 through September 1999 period, the ERBS shortwave sensor responses were found to decrease as much as 8.8% when the quartz filter transmittances decreased due to direct exposure to TSI. On October 6, 1999, the on-board ERBS calibration systems failed. To estimate the 1999-2004, ERBS sensor response changes, the 1984-1997 NOAA-9, and 1986-1995 NOAA-10 Spacecraft ERBE ACR responses were used to characterize response changes as a function of exposure time. The NOAA-9 and NOAA-10 ACR responses decreased as much as 10% due to higher integrated TSI exposure times. In this paper, for each of the ERBS, NOAA-9, and NOAA-10 Spacecraft platforms, the solar calibrations of the ERBE sensor responses are described as well as the derived ERBE sensor response changes as a function of TSI exposure time. For the 1984-2003 ERBS data sets, it is estimated that the calibrated ERBE earth-reflected TSI measurements have precisions approaching 0.2 Watts-per-squared-meter at satellite altitudes.

Earth radiation budget measurement from a spinning satellite: Conceptual design of detectors

NASA Technical Reports Server (NTRS)

Sromovsky, L. A.; Revercomb, H. E.; Suomi, V. E.

1975-01-01

The conceptual design, sensor characteristics, sensor performance and accuracy, and spacecraft and orbital requirements for a spinning wide-field-of-view earth energy budget detector were investigated. The scientific requirements for measurement of the earth's radiative energy budget are presented. Other topics discussed include the observing system concept, solar constant radiometer design, plane flux wide FOV sensor design, fast active cavity theory, fast active cavity design and error analysis, thermopile detectors as an alternative, pre-flight and in-flight calibration plane, system error summary, and interface requirements.

Earth Radiation Budget Experiment (ERBE) scanner instrument anomaly investigation

NASA Technical Reports Server (NTRS)

Watson, N. D.; Miller, J. B.; Taylor, L. V.; Lovell, J. B.; Cox, J. W.; Fedors, J. C.; Kopia, L. P.; Holloway, R. M.; Bradley, O. H.

1985-01-01

The results of an ad-hoc committee investigation of in-Earth orbit operational anomalies noted on two identical Earth Radiation Budget Experiment (ERBE) Scanner instruments on two different spacecraft busses is presented. The anomalies are attributed to the bearings and the lubrication scheme for the bearings. A detailed discussion of the pertinent instrument operations, the approach of the investigation team and the current status of the instruments now in Earth orbit is included. The team considered operational changes for these instruments, rework possibilities for the one instrument which is waiting to be launched, and preferable lubrication considerations for specific space operational requirements similar to those for the ERBE scanner bearings.

Nimbus-6 and -7 Earth Radiation Budget (ERB) sensor details and component tests

NASA Technical Reports Server (NTRS)

Soule, H. V.; Kyle, H. L.; Jacobowitz, H.; Hickey, J.

1983-01-01

Construction details and operating characteristics are described for the thermopile (used in the solar and fixed-Earth channels) and the pyroelectric detector (used in the Earth-scanning channels) carried on the Nimbus 6 and the Nimbus 7 satellites for gathering Earth radiation budget data. Properties of the black coating for the detectors, and sensor testing and calibration are discussed.

Data analysis and software support for the Earth radiation budget experiment

NASA Technical Reports Server (NTRS)

Edmonds, W.; Natarajan, S.

1987-01-01

Computer programming and data analysis efforts were performed in support of the Earth Radiation Budget Experiment (ERBE) at NASA/Langley. A brief description of the ERBE followed by sections describing software development and data analysis for both prelaunch and postlaunch instrument data are presented.

Comparison of the measured and predicted response of the Earth Radiation Budget Experiment active cavity radiometer during solar observations

NASA Technical Reports Server (NTRS)

Mahan, J. R.; Tira, N. E.; Lee, Robert B., III; Keynton, R. J.

1989-01-01

The Earth Radiation Budget Experiment consists of an array of radiometric instruments placed in earth orbit by the National Aeronautics and Space Administration to monitor the longwave and visible components of the earth's radiation budget. Presented is a dynamic electrothermal model of the active cavity radiometer used to measure the earth's total radiative exitance. Radiative exchange is modeled using the Monte Carlo method and transient conduction is treated using the finite element method. Also included is the feedback circuit which controls electrical substitution heating of the cavity. The model is shown to accurately predict the dynamic response of the instrument during solar calibration.

Cloud types and the tropical Earth radiation budget, revised

NASA Technical Reports Server (NTRS)

Dhuria, Harbans L.; Kyle, H. Lee

1989-01-01

Nimbus-7 cloud and Earth radiation budget data are compared in a study of the effects of clouds on the tropical radiation budget. The data consist of daily averages over fixed 500 sq km target areas, and the months of July 1979 and January 1980 were chosen to show the effect of seasonal changes. Six climate regions, consisting of 14 to 24 target areas each, were picked for intensive analysis because they exemplified the range in the tropical cloud/net radiation interactions. The normal analysis was to consider net radiation as the independent variable and examine how cloud cover, cloud type, albedo and emitted radiation varied with the net radiation. Two recurring themes keep repeating on a local, regional, and zonal basis: the net radiation is strongly influenced by the average cloud type and amount present, but most net radiation values could be produced by several combinations of cloud types and amount. The regions of highest net radiation (greater than 125 W/sq m) tend to have medium to heavy cloud cover. In these cases, thin medium altitude clouds predominate. Their cloud tops are normally too warm to be classified as cirrus by the Nimbus cloud algorithm. A common feature in the tropical oceans are large regions where the total regional cloud cover varies from 20 to 90 percent, but with little regional difference in the net radiation. The monsoon and rain areas are high net radiation regions.

Study of the effect of cloud inhomogeneity on the earth radiation budget experiment

NASA Technical Reports Server (NTRS)

Smith, Phillip J.

1988-01-01

The Earth Radiation Budget Experiment (ERBE) is the most recent and probably the most intensive mission designed to gather precise measurements of the Earth's radiation components. The data obtained from ERBE is of great importance for future climatological studies. A statistical study reveals that the ERBE scanner data are highly correlated and that instantaneous measurements corresponding to neighboring pixels contain almost the same information. Analyzing only a fraction of the data set when sampling is suggested and applications of this strategy are given in the calculation of the albedo of the Earth and of the cloud-forcing over ocean.

Science support for the Earth radiation budget sensor on the Nimbus-7 spacecraft

NASA Technical Reports Server (NTRS)

Ingersoll, A. P.

1982-01-01

Experimental data supporting the Earth radiation budget sensor on the Nimbus 7 Satellite is given. The data deals with the empirical relations between radiative flux, cloudiness, and other meteorological parameters; response of a zonal climate ice sheet model to the orbital perturbations during the quaternary ice ages; and a simple parameterization for ice sheet ablation rate.

Observing the earth radiation budget from satellites - Past, present, and a look to the future

NASA Technical Reports Server (NTRS)

House, F. B.

1985-01-01

Satellite measurements of the radiative exchange between the planet earth and space have been the objective of many experiments since the beginning of the space age in the late 1950's. The on-going mission of the Earth Radiation Budget (ERB) experiments has been and will be to consider flight hardware, data handling and scientific analysis methods in a single design strategy. Research and development on observational data has produced an analysis model of errors associated with ERB measurement systems on polar satellites. Results show that the variability of reflected solar radiation from changing meteorology dominates measurement uncertainties. As an application, model calculations demonstrate that measurement requirements for the verification of climate models may be satisfied with observations from one polar satellite, provided there is information on diurnal variations of the radiation budget from the ERBE mission.

Modeling and characterization of the Earth Radiation Budget Experiment (ERBE) nonscanner and scanner sensors

NASA Technical Reports Server (NTRS)

Halyo, Nesim; Pandey, Dhirendra K.; Taylor, Deborah B.

1989-01-01

The Earth Radiation Budget Experiment (ERBE) is making high-absolute-accuracy measurements of the reflected solar and Earth-emitted radiation as well as the incoming solar radiation from three satellites: ERBS, NOAA-9, and NOAA-10. Each satellite has four Earth-looking nonscanning radiometers and three scanning radiometers. A fifth nonscanner, the solar monitor, measures the incoming solar radiation. The development of the ERBE sensor characterization procedures are described using the calibration data for each of the Earth-looking nonscanners and scanners. Sensor models for the ERBE radiometers are developed including the radiative exchange, conductive heat flow, and electronics processing for transient and steady state conditions. The steady state models are used to interpret the sensor outputs, resulting in the data reduction algorithms for the ERBE instruments. Both ground calibration and flight calibration procedures are treated and analyzed. The ground and flight calibration coefficients for the data reduction algorithms are presented.

Dual view Geostationary Earth Radiation Budget from the Meteosat Second Generation satellites.

NASA Astrophysics Data System (ADS)

Dewitte, Steven; Clerbaux, Nicolas; Ipe, Alessandro; Baudrez, Edward; Moreels, Johan

2017-04-01

The diurnal cycle of the radiation budget is a key component of the tropical climate. The geostationary Meteosat Second Generation (MSG) satellites carrying both the broadband Geostationary Earth Radiation Budget (GERB) instrument with nadir resolution of 50 km and the multispectral Spinning Enhanced VIsible and InfraRed Imager (SEVIRI) with nadir resolution of 3 km offer a unique opportunity to observe this diurnal cycle. The geostationary orbit has the advantage of good temporal sampling but the disadvantage of fixed viewing angles, which makes the measurements of the broadband Top Of Atmosphere (TOA) radiative fluxes more sensitive to angular dependent errors. The Meteosat-10 (MSG-3) satellite observes the earth from the standard position at 0° longitude. From October 2016 onwards the Meteosat-8 (MSG-1) satellite makes observations from a new position at 41.5° East over the Indian Ocean. The dual view from Meteosat-8 and Meteosat-10 allows the assessment and correction of angular dependent systematic errors of the flux estimates. We demonstrate this capability with the validation of a new method for the estimation of the clear-sky TOA albedo from the SEVIRI instruments.

Earth Radiation Measurement Science

NASA Technical Reports Server (NTRS)

Smith, G. Louis

2000-01-01

This document is the final report for NASA Grant NAG1-1959, 'Earth Radiation Measurement Science'. The purpose of this grant was to perform research in this area for the needs of the Clouds and Earth Radiant Energy System (CERES) project and for the Earth Radiation Budget Experiment (ERBE), which are bing conducted by the Radiation and Aerosols Branch of the Atmospheric Sciences Division of Langley Research Center. Earth Radiation Measurement Science investigates the processes by which measurements are converted into data products. Under this grant, research was to be conducted for five tasks: (1) Point Response Function Measurements; (2) Temporal Sampling of Outgoing Longwave Radiation; (3) Spatial Averaging of Radiation Budget Data; (4) CERES Data Validation and Applications; and (5) ScaRaB Data Validation and Application.

Science support for the Earth radiation budget experiment

NASA Technical Reports Server (NTRS)

Coakley, James A., Jr.

1994-01-01

The work undertaken as part of the Earth Radiation Budget Experiment (ERBE) included the following major components: The development and application of a new cloud retrieval scheme to assess errors in the radiative fluxes arising from errors in the ERBE identification of cloud conditions. The comparison of the anisotropy of reflected sunlight and emitted thermal radiation with the anisotropy predicted by the Angular Dependence Models (ADM's) used to obtain the radiative fluxes. Additional studies included the comparison of calculated longwave cloud-free radiances with those observed by the ERBE scanner and the use of ERBE scanner data to track the calibration of the shortwave channels of the Advanced Very High Resolution Radiometer (AVHRR). Major findings included: the misidentification of cloud conditions by the ERBE scene identification algorithm could cause 15 percent errors in the shortwave flux reflected by certain scene types. For regions containing mixtures of scene types, the errors were typically less than 5 percent, and the anisotropies of the shortwave and longwave radiances exhibited a spatial scale dependence which, because of the growth of the scanner field of view from nadir to limb, gave rise to a view zenith angle dependent bias in the radiative fluxes.

The earth radiation budget experiment: Early validation results

NASA Astrophysics Data System (ADS)

Smith, G. Louis; Barkstrom, Bruce R.; Harrison, Edwin F.

The Earth Radiation Budget Experiment (ERBE) consists of radiometers on a dedicated spacecraft in a 57° inclination orbit, which has a precessional period of 2 months, and on two NOAA operational meteorological spacecraft in near polar orbits. The radiometers include scanning narrow field-of-view (FOV) and nadir-looking wide and medium FOV radiometers covering the ranges 0.2 to 5 μm and 5 to 50 μm and a solar monitoring channel. This paper describes the validation procedures and preliminary results. Each of the radiometer channels underwent extensive ground calibration, and the instrument packages include in-flight calibration facilities which, to date, show negligible changes of the instruments in orbit, except for gradual degradation of the suprasil dome of the shortwave wide FOV (about 4% per year). Measurements of the solar constant by the solar monitors, wide FOV, and medium FOV radiometers of two spacecraft agree to a fraction of a percent. Intercomparisons of the wide and medium FOV radiometers with the scanning radiometers show agreement of 1 to 4%. The multiple ERBE satellites are acquiring the first global measurements of regional scale diurnal variations in the Earth's radiation budget. These diurnal variations are verified by comparison with high temporal resolution geostationary satellite data. Other principal investigators of the ERBE Science Team are: R. Cess, SUNY, Stoneybrook; J. Coakley, NCAR; C. Duncan, M. King and A Mecherikunnel, Goddard Space Flight Center, NASA; A. Gruber and A.J. Miller, NOAA; D. Hartmann, U. Washington; F.B. House, Drexel U.; F.O. Huck, Langley Research Center, NASA; G. Hunt, Imperial College, London U.; R. Kandel and A. Berroir, Laboratory of Dynamic Meteorology, Ecole Polytechique; V. Ramanathan, U. Chicago; E. Raschke, U. of Cologne; W.L. Smith, U. of Wisconsin and T.H. Vonder Haar, Colorado State U.

Atlas of albedo and absorbed solar radiation derived from Nimbus 7 earth radiation budget data set, November 1985 to October 1987

NASA Technical Reports Server (NTRS)

Smith, G. Louis; Rutan, David; Bess, T. Dale

1992-01-01

An atlas of monthly mean global contour maps of albedo and absorbed solar radiation is presented for 21 months from Nov. 1985 to Oct. 1987. These data were retrieved from measurements made by the shortwave wide-field-of-view radiometer of the Earth Radiation Budget (ERB) instrument aboard the Nimbus 7 spacecraft. Profiles of zonal mean albedos and absorbed solar radiation were tabulated. These geographical distributions are provided as a resource for researchers studying the radiation budget of the Earth. The El Nino/Southern Oscillation event of 1986-1987 is included in this data set. This atlas of albedo and absorbed solar radiation extends to 12 years the period covered by two similar atlases: NASA RP-1230 (Jul. 1975 - Oct. 1978) and NASA RP-1231 (Nov. 1978 - Oct. 1985). These three compilations complement the atlases of outgoing longwave radiation by Bess and Smith in NASA RP-1185, RP-1186, and RP-1261, which were also based on the Nimbus 6 and 7 ERB data.

Simulation and Correction of Triana-Viewed Earth Radiation Budget with ERBE/ISCCP Data

NASA Technical Reports Server (NTRS)

Huang, Jian-Ping; Minnis, Patrick; Doelling, David R.; Valero, Francisco P. J.

2002-01-01

This paper describes the simulation of the earth radiation budget (ERB) as viewed by Triana and the development of correction models for converting Trianaviewed radiances into a complete ERB. A full range of Triana views and global radiation fields are simulated using a combination of datasets from ERBE (Earth Radiation Budget Experiment) and ISCCP (International Satellite Cloud Climatology Project) and analyzed with a set of empirical correction factors specific to the Triana views. The results show that the accuracy of global correction factors to estimate ERB from Triana radiances is a function of the Triana position relative to the Lagrange-1 (L1) or the Sun location. Spectral analysis of the global correction factor indicates that both shortwave (SW; 0.2 - 5.0 microns) and longwave (LW; 5 -50 microns) parameters undergo seasonal and diurnal cycles that dominate the periodic fluctuations. The diurnal cycle, especially its amplitude, is also strongly dependent on the seasonal cycle. Based on these results, models are developed to correct the radiances for unviewed areas and anisotropic emission and reflection. A preliminary assessment indicates that these correction models can be applied to Triana radiances to produce the most accurate global ERB to date.

OPERA: a small-size concept for Earth radiation budget scanning radiometers

NASA Astrophysics Data System (ADS)

Batut, Thierry; Bozec, Xavier; Carel, Jean-Louis; Mercier Ythier, Renaud; Truchot, X.

2018-04-01

SFIM Industries has designed a new radiometer for satellite observation of the earth radiation budget at the top of the a1mosphere. Compared to previous instruments. this new radiometer halfs costs. mass and probability of failure. while it improves radiometric performance significantly. The key idea to achieve these goals is to multiplex the various spectral channels of the instrument. This paper describes this new small size instrument and focuses on its advantages and shortcomings.

Influence of Ice Cloud Microphysics on Imager-Based Estimates of Earth's Radiation Budget

NASA Astrophysics Data System (ADS)

Loeb, N. G.; Kato, S.; Minnis, P.; Yang, P.; Sun-Mack, S.; Rose, F. G.; Hong, G.; Ham, S. H.

2016-12-01

A central objective of the Clouds and the Earth's Radiant Energy System (CERES) is to produce a long-term global climate data record of Earth's radiation budget from the TOA down to the surface along with the associated atmospheric and surface properties that influence it. CERES relies on a number of data sources, including broadband radiometers measuring incoming and reflected solar radiation and OLR, high-resolution spectral imagers, meteorological, aerosol and ozone assimilation data, and snow/sea-ice maps based on microwave radiometer data. While the TOA radiation budget is largely determined directly from accurate broadband radiometer measurements, the surface radiation budget is derived indirectly through radiative transfer model calculations initialized using imager-based cloud and aerosol retrievals and meteorological assimilation data. Because ice cloud particles exhibit a wide range of shapes, sizes and habits that cannot be independently retrieved a priori from passive visible/infrared imager measurements, assumptions about the scattering properties of ice clouds are necessary in order to retrieve ice cloud optical properties (e.g., optical depth) from imager radiances and to compute broadband radiative fluxes. This presentation will examine how the choice of an ice cloud particle model impacts computed shortwave (SW) radiative fluxes at the top-of-atmosphere (TOA) and surface. The ice cloud particle models considered correspond to those from prior, current and future CERES data product versions. During the CERES Edition2 (and Edition3) processing, ice cloud particles were assumed to be smooth hexagonal columns. In the Edition4, roughened hexagonal columns are assumed. The CERES team is now working on implementing in a future version an ice cloud particle model comprised of a two-habit ice cloud model consisting of roughened hexagonal columns and aggregates of roughened columnar elements. In each case, we use the same ice particle model in both the

The constrained inversion of Nimbus-7 wide field-of-view radiometer measurements for the Earth Radiation Budget

NASA Technical Reports Server (NTRS)

Hucek, Richard R.; Ardanuy, Philip; Kyle, H. Lee

1990-01-01

The results of a constrained, wide field-of-view radiometer measurement deconvolution are presented and compared against higher resolution results obtained from the Earth Radiation Budget instrument on the Nimbus-7 satellite and from the Earth Radiation Budget Experiment. The method is applicable to both longwave and shortwave observations and is specifically designed to treat the problem of anisotropic reflection and emission at the top of the atmosphere as well as low signal-to-noise ratios that arise regionally within a field. The procedure is reviewed, and the improvements in resolution obtained are examined. Some minor improvements in the albedo algorithm are also described.

The effect of clouds on the earth's radiation budget

NASA Technical Reports Server (NTRS)

Ziskin, Daniel; Strobel, Darrell F.

1991-01-01

The radiative fluxes from the Earth Radiation Budget Experiment (ERBE) and the cloud properties from the International Satellite Cloud Climatology Project (ISCCP) over Indonesia for the months of June and July of 1985 and 1986 were analyzed to determine the cloud sensitivity coefficients. The method involved a linear least squares regression between co-incident flux and cloud coverage measurements. The calculated slope is identified as the cloud sensitivity. It was found that the correlations between the total cloud fraction and radiation parameters were modest. However, correlations between cloud fraction and IR flux were improved by separating clouds by height. Likewise, correlations between the visible flux and cloud fractions were improved by distinguishing clouds based on optical depth. Calculating correlations between the net fluxes and either height or optical depth segregated cloud fractions were somewhat improved. When clouds were classified in terms of their height and optical depth, correlations among all the radiation components were improved. Mean cloud sensitivities based on the regression of radiative fluxes against height and optical depth separated cloud types are presented. Results are compared to a one-dimensional radiation model with a simple cloud parameterization scheme.

Deconvolution and analysis of wide-angle longwave radiation data from Nimbus 6 Earth radiation budget experiment for the first year

NASA Technical Reports Server (NTRS)

Bess, T. D.; Green, R. N.; Smith, G. L.

1980-01-01

One year of longwave radiation data from July 1975 through June 1976 from the Nimbus 6 satellite Earth radiation budget experiment is analyzed by representing the radiation field by a spherical harmonic expansion. The data are from the wide field of view instrument. Contour maps of the longwave radiation field and spherical harmonic coefficients to degree 12 and order 12 are presented for a 12 month data period.

Atlas of wide-field-of-view outgoing longwave radiation derived from Nimbus 7 Earth radiation budget data set, November 1985 to October 1987

NASA Technical Reports Server (NTRS)

Bess, T. Dale; Smith, G. Louis

1991-01-01

An atlas of monthly outgoing longwave radiation global contour maps and associated spherical harmonic coefficients is presented. The atlas contains 23 months of data from November 1985 to October 1987 . The data were derived from the second Earth Radiation Budget (ERB) package, which was flown on the Nimbus 7 Sun-synchronous satellite in 1987. This data set is a companion set and extension to similar atlases that documented 10 years of outgoing longwave radiation results from Nimbus 6 and Nimbus 7 satellites. This atlas and the companion atlases give a data set covering a 12-year time period and will be very useful in studying different aspects of our changing climate. The data set also provides a 3-year overlap with the current Earth Radiation Budget Experiment (ERBE).

Validation and analysis of Earth Radiation Budget active-cavity radiometric data (1985-1999)

NASA Astrophysics Data System (ADS)

Paden, Jack; Smith, G. Louis; Lee, Robert B., III; Priestley, Kory J.; Pandey, Dhirendra K.; Wilson, Robert S.

2001-01-01

On 5 October 1984, the US' first woman in space, Dr. Sally Ride, inserted the Earth Radiation Budget Satellite (ERBS) into a 57 degree inclined orbit using the shuttles remote manipulator arm. The orbital precession period of the satellite was 72 days. The nonscanner instrument aboard the ERBS has acquired earth-emitted and reflected radiant flux data since that time, having exceeded its designed lifetime of three years by a factor of five. During these 15 years, the ERBS nonscanner has become a de-facto standard to which much remotely sensed radiative flux data is compared. This paper compares the fifteen year history of the ERBS wide and medium field-of-view non-scanner detectors with the solar irradiance data acquired by the co-located ERBS solar monitor and with the National Climatic Data Center's earth- surface temperature dataset for the same period.

Atlas of the Earth's radiation budget as measured by Nimbus-7: May 1979 to May 1980

NASA Technical Reports Server (NTRS)

Kyle, H. Lee; Hucek, Richard R.; Vallette, Brenda J.

1991-01-01

This atlas describes the seasonal changes in the Earth's radiation budget for the 13-month period, May 1979 to May 1980. It helps to illustrate the strong feedback mechanisms by which the Earth's climate interacts with the top-of-the-atmosphere insolation to modify the energy that various regions absorb from the Sun. Cloud type and cloud amount, which are linked to the surface temperature and the regional climate, are key elements in this interaction. Annual, seasonal, and monthly maps of the albedo, outgoing longwave and net radiation, noontime cloud cover, and mean diurnal surface temperatures are presented. Annual and seasonal net cloud forcing maps are also given. All of the quantities were derived from Nimbus-7 satellite measurements except for the temperatures, which were used in the cloud detection algorithm and came originally from the Air Force 3-dimensional nephanalysis dataset. The seasonal changes are described. The interaction of clouds and the radiation budget is briefly discussed.

Optimum satellite orbits for accurate measurement of the earth's radiation budget, summary

NASA Technical Reports Server (NTRS)

Campbell, G. G.; Vonderhaar, T. H.

1978-01-01

The optimum set of orbit inclinations for the measurement of the earth radiation budget from spacially integrating sensor systems was estimated for two and three satellite systems. The best set of the two were satellites at orbit inclinations of 80 deg and 50 deg; of three the inclinations were 80 deg, 60 deg and 50 deg. These were chosen on the basis of a simulation of flat plate and spherical detectors flying over a daily varying earth radiation field as measured by the Nimbus 3 medium resolution scanners. A diurnal oscillation was also included in the emitted flux and albedo to give a source field as realistic as possible. Twenty three satellites with different inclinations and equator crossings were simulated, allowing the results of thousand of multisatellite sets to be intercompared. All were circular orbits of radius 7178 kilometers.

Angular radiation models for earth-atmosphere system. Volume 2: Longwave radiation

NASA Technical Reports Server (NTRS)

Suttles, J. T.; Green, R. N.; Smith, G. L.; Wielicki, B. A.; Walker, I. J.; Taylor, V. R.; Stowe, L. L.

1989-01-01

The longwave angular radiation models that are required for analysis of satellite measurements of Earth radiation, such as those from the Earth Radiation Budget Experiment (ERBE) are presented. The models contain limb-darkening characteristics and mean fluxes. Limb-darkening characteristics are the longwave anisotropic factor and the standard deviation of the longwave radiance. Derivation of these models from the Nimbus 7 ERB (Earth Radiation Budget) data set is described. Tabulated values and computer-generated plots are included for the limb-darkening and mean-flux models.

The budget of biologically active ultraviolet radiation in the earth-atmosphere system

NASA Technical Reports Server (NTRS)

Frederick, John E.; Lubin, Dan

1988-01-01

This study applies the concept of a budget to describe the interaction of solar ultraviolet (UV) radiation with the earth-atmosphere system. The wavelength ranges of interest are the biologically relevant UV-B between 280 and 320 nm and the UV-A from 32000 to 400 nm. The Nimbus 7 solar backscattered ultraviolet (SBUV) instrument provides measurements of total column ozone and information concerning cloud cover which, in combination with a simple model of radiation transfer, define the fractions of incident solar irradiance absorbed in the atmosphere, reflected to space, and absorbed at the ground. Results for the month of July quantify the contribution of fractional cloud cover and cloud optical thickness to the radiation budget's three components. Scattering within a thick cloud layer makes the downward radiation field at the cloud base more isotropic than is the case for clear skies. For small solar zenith angles, typical of summer midday conditions, the effective pathlength of this diffuse irradiance through tropospheric ozone is greater than that under clear-sky conditions. The result is an enhanced absorption of UV-B radiation in the troposphere during cloud-covered conditions. Major changes in global cloud cover or cloud optical thicknesses could alter the ultraviolet radiation received by the biosphere by an amount comparable to that predicted for long-term trends in ozone.

Wave energy budget analysis in the Earth's radiation belts uncovers a missing energy.

PubMed

Artemyev, A V; Agapitov, O V; Mourenas, D; Krasnoselskikh, V V; Mozer, F S

2015-05-15

Whistler-mode emissions are important electromagnetic waves pervasive in the Earth's magnetosphere, where they continuously remove or energize electrons trapped by the geomagnetic field, controlling radiation hazards to satellites and astronauts and the upper-atmosphere ionization or chemical composition. Here, we report an analysis of 10-year Cluster data, statistically evaluating the full wave energy budget in the Earth's magnetosphere, revealing that a significant fraction of the energy corresponds to hitherto generally neglected very oblique waves. Such waves, with 10 times smaller magnetic power than parallel waves, typically have similar total energy. Moreover, they carry up to 80% of the wave energy involved in wave-particle resonant interactions. It implies that electron heating and precipitation into the atmosphere may have been significantly under/over-valued in past studies considering only conventional quasi-parallel waves. Very oblique waves may turn out to be a crucial agent of energy redistribution in the Earth's radiation belts, controlled by solar activity.

The basic thermodynamics of Earth's radiation budget

NASA Astrophysics Data System (ADS)

Ward, Peter L.

2015-04-01

greenhouse gases. There simply is not enough thermal energy absorbed by greenhouse gases to have a major effect on global warming. Computer programs used to quantify greenhouse-gas theory overestimate infrared energies because they assume that thermal energy travels in space as waves, for which energy is a function of amplitude squared, and that energies are additive over bandwidth, both properties that are very different from the observed behavior of radiation in the atmosphere. Heat only flows from hot to cold; it cannot flow from a colder layer in the atmosphere to a warmer Earth, as assumed in many radiation budgets (e.g. Wild et al., 2013); you cannot get warmer by standing next to a cold stove. According to Planck's Law, radiation from a body of matter does not have high enough frequencies or amplitudes to warm the same body, as is assumed by greenhouse-gas theory. Warming radiation must come from a warmer body. Detailed observations of global warming, including the recent hiatus, are explained much more directly and clearly by ozone depletion theory, where less ozone in the stratosphere allows more high-energy, solar ultraviolet radiation to reach Earth, cooling the stratosphere, warming the oceans. More details at ozonedepletiontheory.info plus a video at tinyurl.com/ozone-depletion-theory.

First decadal lunar results from the Moon and Earth Radiation Budget Experiment.

PubMed

Matthews, Grant

2018-03-01

A need to gain more confidence in computer model predictions of coming climate change has resulted in greater analysis of the quality of orbital Earth radiation budget (ERB) measurements being used today to constrain, validate, and hence improve such simulations. These studies conclude from time series analysis that for around a quarter of a century, no existing satellite ERB climate data record is of a sufficient standard to partition changes to the Earth from those of un-tracked and changing artificial instrumentation effects. This led to the creation of the Moon and Earth Radiation Budget Experiment (MERBE), which instead takes existing decades old climate data to a higher calibration standard using thousands of scans of Earth's Moon. The Terra and Aqua satellite ERB climate records have been completely regenerated using signal-processing improvements, combined with a substantial increase in precision from more comprehensive in-flight spectral characterization techniques. This study now builds on previous Optical Society of America work by describing new Moon measurements derived using accurate analytical mapping of telescope spatial response. That then allows a factor of three reduction in measurement noise along with an order of magnitude increase in the number of retrieved independent lunar results. Given decadal length device longevity and the use of solar and thermal lunar radiance models to normalize the improved ERB results to the International System of Units traceable radiance scale of the "MERBE Watt," the same established environmental time series analysis techniques are applied to MERBE data. They evaluate it to perhaps be of sufficient quality to immediately begin narrowing the largest of climate prediction uncertainties. It also shows that if such Terra/Aqua ERB devices can operate into the 2020s, it could become possible to halve these same uncertainties decades sooner than would be possible with existing or even planned new observing systems.

Investigation of Next-Generation Earth Radiation Budget Radiometry

NASA Technical Reports Server (NTRS)

Coffey, Katherine L.; Mahan, J. R.

1999-01-01

The current effort addresses two issues important to the research conducted by the Thermal Radiation Group at Virginia Tech. The first research topic involves the development of a method which can properly model the diffraction of radiation as it enters an instrument aperture. The second topic involves the study of a potential next-generation space-borne radiometric instrument concept. Presented are multiple modeling efforts to describe the diffraction of monochromatic radiant energy passing through an aperture for use in the Monte-Carlo ray-trace environment. Described in detail is a deterministic model based upon Heisenberg's uncertainty principle and the particle theory of light. This method is applicable to either Fraunhofer or Fresnel diffraction situations, but is incapable of predicting the secondary fringes in a diffraction pattern. Also presented is a second diffraction model, based on the Huygens-Fresnel principle with a correcting obliquity factor. This model is useful for predicting Fraunhofer diffraction, and can predict the secondary fringes because it keeps track of phase. NASA is planning for the next-generation of instruments to follow CERES (Clouds and the Earth's Radiant Energy System), an instrument which measures components of the Earth's radiant energy budget in three spectral bands. A potential next-generation concept involves modification of the current CERES instrument to measure in a larger number of wavelength bands. This increased spectral partitioning would be achieved by the addition of filters and detectors to the current CERES geometry. The capacity of the CERES telescope to serve for this purpose is addressed in this thesis.

Observation of The Top of The Atmosphere Outgoing Longwave Radiation Using The Geostationary Earth Radiation Budget Sensor

NASA Astrophysics Data System (ADS)

Spencer, G.; Llewellyn-Jones, D.

In the summer of 2002 the Meteosat Second Generation (MSG) satellite is due to be launched. On board the MSG satellite is the Geostationary Earth Radiation Budget (GERB) sensor. This is a new radiometer that will be able to observe and measure the outgoing longwave radiation from the top of the atmosphere for the whole ob- served Earth disc, due to its unique position in geostationary orbit. Every 15 minutes the GERB sensor will make a full Earth disc observation, centred on the Greenwich meridian. Thus, the GERB sensor will provide unprecedented coupled temporal and spatial resolution of the outgoing longwave radiation (4.0 to 30.0 microns), by first measuring the broadband radiation (0.32 to 30.0 microns) and then subtracting the measured reflected shortwave solar radiation (0.32 to 4.0 microns), from the earth- atmosphere system. The GERB sensor is able to make measurements to within an accuracy of 1 W/sq. m. A forward model is being developed at Leicester to simulate the data from the GERB sensor for representative geophysical scenes and to investigate key parameters and processes that will affect the top of the atmosphere signal. At the heart of this model is a line-by-line radiative transfer model, the Oxford Reference Forward Model (RFM) that is to be used with model atmospheres generated from ECMWF analysis data. When MSG is launched, cloud data from the Spinning Enhanced Visible and Infrared Imager (SEVIRI), also on board, is to be used in conjunction with GERB data.

Studies of radiative transfer in the earth's atmosphere with emphasis on the influence of the radiation budget in the joint institute for advancement of flight sciences at the NASA-Langley Research Center

NASA Technical Reports Server (NTRS)

1979-01-01

Earth and solar radiation budget measurements were examined. Sensor calibration and measurement accuracy were emphasized. Past works on the earth's radiation field that must be used in reducing observations of the radiation field were reviewed. Using a finite difference radiative transfer algorithm, models of the angular and spectral dependence of the earth's radiation field were developed.

Measurements of the earth radiation budget from satellites during the first GARP global experiment

NASA Technical Reports Server (NTRS)

Vonder Haar, T. H.; Campbell, G. G.; Smith, E. A.; Arking, A.; Coulson, K.; Hickey, J.; House, F.; Ingersoll, A.; Jacobowitz, H.; Smith, L.

1981-01-01

Radiation budget data (which will aid in climate model development) and solar constant measurements (both to be used for the study of long term climate change and interannual seasonal weather variability) are presented, obtained during Nimbus-6 and Nimbus-7 satellite flights, using wide-field-of-view, scanner, and black cavity detectors. Data on the solar constant, described as a function of the date of measurement, are given. The unweighed mean amounts to 1377 + or - 20 per sq Wm, with a standard deviation of 8 per sq Wm. The new solar data are combined with earlier measurements, and it is suggested that the total absolute energy output of the sun is a minimum at 'solar maximum' and vice versa. Attention is given to the measurements of the net radiation budget, the planetary albedo, and the infrared radiant exitance. The annual and semiannual cycles of normal variability explain most of the variance of energy exchange between the earth and space. Examination of separate ocean and atmospheric energy budgets implies a net continent-ocean region energy exchange.

The effects of atmospheric chemistry on radiation budget in the Community Earth Systems Model

NASA Astrophysics Data System (ADS)

Choi, Y.; Czader, B.; Diao, L.; Rodriguez, J.; Jeong, G.

2013-12-01

The Community Earth Systems Model (CESM)-Whole Atmosphere Community Climate Model (WACCM) simulations were performed to study the impact of atmospheric chemistry on the radiation budget over the surface within a weather prediction time scale. The secondary goal is to get a simplified and optimized chemistry module for the short time period. Three different chemistry modules were utilized to represent tropospheric and stratospheric chemistry, which differ in how their reactions and species are represented: (1) simplified tropospheric and stratospheric chemistry (approximately 30 species), (2) simplified tropospheric chemistry and comprehensive stratospheric chemistry from the Model of Ozone and Related Chemical Tracers, version 3 (MOZART-3, approximately 60 species), and (3) comprehensive tropospheric and stratospheric chemistry (MOZART-4, approximately 120 species). Our results indicate the different details in chemistry treatment from these model components affect the surface temperature and impact the radiation budget.

Angular radiation models for Earth-atmosphere system. Volume 1: Shortwave radiation

NASA Technical Reports Server (NTRS)

Suttles, J. T.; Green, R. N.; Minnis, P.; Smith, G. L.; Staylor, W. F.; Wielicki, B. A.; Walker, I. J.; Young, D. F.; Taylor, V. R.; Stowe, L. L.

1988-01-01

Presented are shortwave angular radiation models which are required for analysis of satellite measurements of Earth radiation, such as those fro the Earth Radiation Budget Experiment (ERBE). The models consist of both bidirectional and directional parameters. The bidirectional parameters are anisotropic function, standard deviation of mean radiance, and shortwave-longwave radiance correlation coefficient. The directional parameters are mean albedo as a function of Sun zenith angle and mean albedo normalized to overhead Sun. Derivation of these models from the Nimbus 7 ERB (Earth Radiation Budget) and Geostationary Operational Environmental Satellite (GOES) data sets is described. Tabulated values and computer-generated plots are included for the bidirectional and directional modes.

Effects of clouds on the Earth radiation budget; Seasonal and inter-annual patterns

NASA Technical Reports Server (NTRS)

Dhuria, Harbans L.

1992-01-01

Seasonal and regional variations of clouds and their effects on the climatological parameters were studied. The climatological parameters surface temperature, solar insulation, short-wave absorbed, long wave emitted, and net radiation were considered. The data of climatological parameters consisted of about 20 parameters of Earth radiation budget and clouds of 2070 target areas which covered the globe. It consisted of daily and monthly averages of each parameter for each target area for the period, Jun. 1979 - May 1980. Cloud forcing and black body temperature at the top of the atmosphere were calculated. Interactions of clouds, cloud forcing, black body temperature, and the climatological parameters were investigated and analyzed.

A history of presatellite investigations of the earth's radiation budget

NASA Technical Reports Server (NTRS)

Hunt, G. E.; Kandel, R.; Mecherikunnel, A. T.

1986-01-01

The history of radiation budget studies from the early twentieth century to the advent of the space age is reviewed. By the beginning of the 1960's, accurate radiative models had been developed capable of estimating the global and zonally averaged components of the radiation budget, though great uncertainty in the derived parameters existed due to inaccuracy of the data describing the physical parameters used in the model, associated with clouds, the solar radiation, and the gaseous atmospheric absorbers. Over the century, the planetary albedo estimates had reduced from 89 to 30 percent.

Re-Examination of the Observed Decadal Variability of Earth Radiation Budget Using Altitude-Corrected ERBE/ERBS Nonscanner WFOV Data

NASA Technical Reports Server (NTRS)

Wong, Takmeng; Wielicki, Bruce A.; Lee, Robert B.; Smith, G. Louis; Bush, Kathryn A.

2005-01-01

This paper gives an update on the observed decadal variability of Earth Radiation Budget using the latest altitude-corrected Earth Radiation Budget Experiment (ERBE)/Earth Radiation Budget Satellite (ERBS) Nonscanner Wide Field of View (WFOV) instrument Edition3 dataset. The effects of the altitude correction are to modify the original reported decadal changes in tropical mean (20N to 20S) longwave (LW), shortwave (SW), and net radiation between the 1980s and the 1990s from 3.1/-2.4/-0.7 to 1.6/-3.0/1.4 Wm(sup -2) respectively. In addition, a small SW instrument drift over the 15-year period was discovered during the validation of the WFOV Edition3 dataset. A correction was developed and applied to the Edition3 dataset at the data user level to produce the WFOV Edition3_Rev1 dataset. With this final correction, the ERBS Nonscanner observed decadal changes in tropical mean LW, SW, and net radiation between the 1980s and the 1990s now stand at 0.7/-2.1/1.4 Wm(sup -2), respectively, which are similar to the observed decadal changes in the HIRS Pathfinder OLR and the ISCCP FD record; but disagree with the AVHRR Pathfinder ERB record. Furthermore, the observed interannual variability of near-global ERBS WFOV Edition3_Rev1 net radiation is found to be remarkably consistent with the latest ocean heat storage record for the overlapping time period of 1993 to 1999. Both data sets show variations of roughly 1.5 Wm(sup -2) in planetary net heat balance during the 1990s.

Think the way to measure the Earth Radiation Budget and the Total Solar Irradiance with a small satellites constellation

NASA Astrophysics Data System (ADS)

Meftah, M.; Keckhut, P.; Damé, L.; Bekki, S.; Sarkissian, A.; Hauchecorne, A.

2018-05-01

Within the past decade, satellites constellations have become possible and practical. One of the interest to use a satellites constellation is to measure the true Earth Radiation Imbalance, which is a crucial quantity for testing climate models and for predicting the future course of global warming. This measurement presents a high interest because the 2001-2010 decade has not shown the accelerating pace of global warming that most models predict, despite the fact that the greenhouse-gas radiative forcing continues to rise. All estimates (ocean heat content and top of atmosphere) show that over the past decade the Earth radiation imbalance ranges between 0.5 to 1W-2. Up to now, the Earth radiation imbalance has not been measured directly. The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar radiations (total solar irradiance) and the outgoing terrestrial radiations (top of atmosphere outgoing longwave radiations and shortwave radiations) onboard the same satellite, and ideally, with the same instrument. The incoming solar radiations and the outgoing terrestrial radiations are of nearly equal magnitude of the order of 340.5W-2. The objective is to measure these quantities over time by using differential Sun-Earth measurements (to counter calibration errors) with an accuracy better than 0.05Wm-2 at 1σ. It is also necessary to have redundant instruments to track aging in space in order to measure during a decade and to measure the global diurnal cycle with a dozen satellites. Solar irradiance and Earth Radiation Budget (SERB) is a potential first in orbit demonstration satellite. The SERB nano-satellite aims to measure on the same platform the different components of the Earth radiation budget and the total solar irradiance. Instrumental payloads (solar radiometer and Earth radiometers) can acquire the technical maturity for the future large missions (constellation that insure global measurement cover) by flying in a

Passive exposure of Earth radiation budget experiment components. LDEF experiment AO-147: Post-flight examinations and tests

NASA Technical Reports Server (NTRS)

Hickey, John R.

1992-01-01

The flight spare sensors of the Earth Radiation Budget (ERB) experiment of the Nimbus 6 and 7 missions were flown aboard the LDEF. The preliminary post retrieval examination and test results are presented here for the sensor windows and filters, the thermopile sensors and a cavity radiometer.

Summary of along-track data from the earth radiation budget satellite for several representative ocean regions

NASA Technical Reports Server (NTRS)

Brooks, David R.; Fenn, Marta A.

1988-01-01

For several days in January and August 1985, the Earth Radiation Budget Satellite, a component of the Earth Radiation Budget Experiment (ERBE), was operated in an along-track scanning mode. A survey of radiance measurements taken in this mode is given for five ocean regions: the north and south Atlantic, the Arabian Sea, the western Pacific north of the Equator, and part of the Intertropical Convergence Zone. Each overflight contains information about the clear scene and three cloud categories: partly cloudy, mostly cloudy, and overcast. The data presented include the variation of longwave and shortwave radiance in each scene classification as a function of viewing zenity angle during each overflight of one of the five target regions. Several features of interest in the development of anisotropic models are evident, including the azimuthal dependence of shortwave radiance that is an essential feature of shortwave bidirectional models. The data also demonstrate that the scene classification algorithm employed by the ERBE results in scene classifications that are a function of viewing geometry.

Summary of along-track data from the Earth radiation budget satellite for several major desert regions

NASA Technical Reports Server (NTRS)

Brooks, David R.; Fenn, Marta A.

1988-01-01

For several days in January and August 1985, the Earth Radiation Budget Satellite, a component of the Earth Radiation Budget Experiment (ERBE), was operated in an along-track scanning mode. A survey of radiance measurements is given for four desert areas in Africa, the Arabian Peninsula, Australia, and the Sahel region of Africa. Each overflight provides radiance information for four scene categories: clear, partly cloudy, mostly cloudy, and overcast. The data presented include the variation of radiance in each scene classification as a function of viewing zenith angle during each overflight of the five target areas. Several features of interest in the development of anisotropic models are evident, including day-night differences in longwave limb darkening and the azimuthal dependence of short wave radiance. There is some evidence that surface features may introduce thermal or visible shadowing that is not incorporated in the usual descriptions of the anisotropic behavior of radiance as viewed from space. The data also demonstrate that the ERBE scene classification algorithms give results that, at least for desert surfaces, are a function of viewing geometry.

Radiation budget and related measurements in 1985 and beyond. [earth radiation budget satellite system

NASA Technical Reports Server (NTRS)

1978-01-01

Development of systems for obtaining radiation budget and cloud data is discussed. Instruments for measuring total solar irradiance, total infrared flux, reflected solar flux, and cloud heights and properties are considered. Other topics discussed include sampling by multiple satellites, user identification, and determination of the parameters that need to be measured.

Nimbus-7 Earth radiation budget calibration history. Part 2: The Earth flux channels

NASA Technical Reports Server (NTRS)

Kyle, H. Lee; Hucek, Douglas Richard R.; Ardanuy, Philip E.; Hickey, John R.; Maschhoff, Robert H.; Penn, Lanning M.; Groveman, Brian S.; Vallette, Brenda J.

1994-01-01

Nine years (November 1978 to October 1987) of Nimbus-7 Earth radiation budget (ERB) products have shown that the global annual mean emitted longwave, absorbed shortwave, and net radiation were constant to within about + 0.5 W/sq m. Further, most of the small annual variations in the emitted longwave have been shown to be real. To obtain this measurement accuracy, the wide-field-of-view (WFOV) Earth-viewing channels 12 (0.2 to over 50 micrometers), 13 (0.2 to 3.8 micrometers), and 14 (0.7 to 2.8 micrometers) have been characterized in their satellite environment to account for signal variations not considered in the prelaunch calibration equations. Calibration adjustments have been derived for (1) extraterrestrial radiation incident on the detectors, (2) long-term degradation of the sensors, and (3) thermal perturbations within the ERB instrument. The first item is important in all the channels; the second, mainly in channels 13 and 14, and the third, only in channels 13 and 14. The Sun is used as a stable calibration source to monitor the long-term degradation of the various channels. Channel 12, which is reasonably stable to both thermal perturbations and sensor degradation, is used as a reference and calibration transfer agent for the drifting sensitivities of the filtered channels 13 and 14. Redundant calibration procedures were utilized. Laboratory studies complemented analyses of the satellite data. Two nearly independent models were derived to account for the thermal perturbations in channels 13 and 14. The global annual mean terrestrial shortwave and longwave signals proved stable enough to act as secondary calibration sources. Instantaneous measurements may still, at times, be in error by as much as a few Wm(exp -2), but the long-term averages are stable to within a fraction of a Wm(exp -2).

Construction of a Matched Global Cloud and Radiance Product from LEO/GEO and EPIC Observations to Estimate Daytime Earth Radiation Budget from DSCOVR

NASA Astrophysics Data System (ADS)

Duda, D. P.; Khlopenkov, K. V.; Palikonda, R.; Khaiyer, M. M.; Minnis, P.; Su, W.; Sun-Mack, S.

2016-12-01

With the launch of the Deep Space Climate Observatory (DSCOVR), new estimates of the daytime Earth radiation budget can computed from a combination of measurements from the two Earth-observing sensors onboard the spacecraft, the Earth Polychromatic Imaging Camera (EPIC) and the National Institute of Standards and Technology Advanced Radiometer (NISTAR). Although these instruments can provide accurate top-of-atmosphere (TOA) radiance measurements, they lack sufficient resolution to provide details on small-scale surface and cloud properties. Previous studies have shown that these properties have a strong influence on the anisotropy of the radiation at the TOA, and ignoring such effects can result in large TOA-flux errors. To overcome these effects, high-resolution scene identification is needed for accurate Earth radiation budget estimation. Selected radiance and cloud property data measured and derived from several low earth orbit (LEO, including NASA Terra and Aqua MODIS, NOAA AVHRR) and geosynchronous (GEO, including GOES (east and west), METEOSAT, INSAT-3D, MTSAT-2, and HIMAWARI-8) satellite imagers were collected to create hourly 5-km resolution global composites of data necessary to compute angular distribution models (ADM) for reflected shortwave (SW) and longwave (LW) radiation. The satellite data provide an independent source of radiance measurements and scene identification information necessary to construct ADMs that are used to determine the daytime Earth radiation budget. To optimize spatial matching between EPIC measurements and the high-resolution composite cloud properties, LEO/GEO retrievals within the EPIC fields of view (FOV) are convolved to the EPIC point spread function (PSF) in a similar manner to the Clouds and the Earth's Radiant Energy System (CERES) Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product. Examples of the merged LEO/GEO/EPIC product will be presented, describing the chosen radiance and cloud properties and

Construction of a Matched Global Cloud and Radiance Product from LEO/GEO and EPIC Observations to Estimate Daytime Earth Radiation Budget from DSCOVR

NASA Technical Reports Server (NTRS)

Duda, David P.; Khlopenkov, Konstantin V.; Thiemann, Mandana; Palikonda, Rabindra; Sun-Mack, Sunny; Minnis, Patrick; Su, Wenying

2016-01-01

With the launch of the Deep Space Climate Observatory (DSCOVR), new estimates of the daytime Earth radiation budget can be computed from a combination of measurements from the two Earth-observing sensors onboard the spacecraft, the Earth Polychromatic Imaging Camera (EPIC) and the National Institute of Standards and Technology Advanced Radiometer (NISTAR). Although these instruments can provide accurate top-of-atmosphere (TOA) radiance measurements, they lack sufficient resolution to provide details on small-scale surface and cloud properties. Previous studies have shown that these properties have a strong influence on the anisotropy of the radiation at the TOA, and ignoring such effects can result in large TOA-flux errors. To overcome these effects, high-resolution scene identification is needed for accurate Earth radiation budget estimation. Selected radiance and cloud property data measured and derived from several low earth orbit (LEO, including NASA Terra and Aqua MODIS, NOAA AVHRR) and geosynchronous (GEO, including GOES (east and west), METEOSAT, INSAT-3D, MTSAT-2, and HIMAWARI-8) satellite imagers were collected to create hourly 5-km resolution global composites of data necessary to compute angular distribution models (ADM) for reflected shortwave (SW) and longwave (LW) radiation. The satellite data provide an independent source of radiance measurements and scene identification information necessary to construct ADMs that are used to determine the daytime Earth radiation budget. To optimize spatial matching between EPIC measurements and the high-resolution composite cloud properties, LEO/GEO retrievals within the EPIC fields of view (FOV) are convolved to the EPIC point spread function (PSF) in a similar manner to the Clouds and the Earth's Radiant Energy System (CERES) Single Scanner Footprint TOA/Surface Fluxes and Clouds (SSF) product. Examples of the merged LEO/GEO/EPIC product will be presented, describing the chosen radiance and cloud properties and

A study of the thermal and optical characteristics of radiometric channels for Earth radiation budget applications

NASA Technical Reports Server (NTRS)

Mahan, J. R.; Tira, Nour E.

1991-01-01

An improved dynamic electrothermal model for the Earth Radiation Budget Experiment (ERBE) total, nonscanning channels is formulated. This model is then used to accurately simulate two types of dynamic solar observation: the solar calibration and the so-called pitchover maneuver. Using a second model, the nonscanner active cavity radiometer (ACR) thermal noise is studied. This study reveals that radiative emission and scattering by the surrounding parts of the nonscanner cavity are acceptably small. The dynamic electrothermal model is also used to compute ACR instrument transfer function. Accurate in-flight measurement of this transfer function is shown to depend on the energy distribution over the frequency spectrum of the radiation input function. A new array-type field of view limiter, whose geometry controls the input function, is proposed for in-flight calibration of an ACR and other types of radiometers. The point spread function (PSF) of the ERBE and the Clouds and Earth's Radiant Energy System (CERES) scanning radiometers is computed. The PSF is useful in characterizing the channel optics. It also has potential for recovering the distribution of the radiative flux from Earth by deconvolution.

The role of earth radiation budget studies in climate and general circulation research

NASA Technical Reports Server (NTRS)

Ramanathan, V.

1987-01-01

The use of earth radiation budget (ERB) data for climate and general circulation research is studied. ERB measurements obtained in the 1960's and 1970's have provided data on planetary brightness, planetary global energy balances, the greenhouse effect, solar insolation, meridional heat transport by oceans and atmospheres, regional forcing, climate feedback processes, and the computation of albedo values in low latitudes. The role of clouds in governing climate, in influencing the general circulation, and in determining the sensitivity of climate to external perturbations needs to be researched; a procedure for analyzing the ERB data, which will address these problems, is described. The approach involves estimating the clear-sky fluxes from the high spatial resolution scanner measurement and defining a cloud radiative forcing; the global average of the sum of the solar and long-wave cloud forcing yields the net radiative effect of clouds on the climate.

Human factors analysis of workstation design: Earth Radiation Budget Satellite Mission Operations Room

NASA Technical Reports Server (NTRS)

Stewart, L. J.; Murphy, E. D.; Mitchell, C. M.

1982-01-01

A human factors analysis addressed three related yet distinct issues within the area of workstation design for the Earth Radiation Budget Satellite (ERBS) mission operation room (MOR). The first issue, physical layout of the MOR, received the most intensive effort. It involved the positioning of clusters of equipment within the physical dimensions of the ERBS MOR. The second issue for analysis was comprised of several environmental concerns, such as lighting, furniture, and heating and ventilation systems. The third issue was component arrangement, involving the physical arrangement of individual components within clusters of consoles, e.g., a communications panel.

CERES FM-5 on the NPP Spacecraft: Continuing the Earth Radiation Budget Climate Data Record

NASA Technical Reports Server (NTRS)

Priestly, Kory; Smith, G. Louis

2009-01-01

The Clouds and the Earth's Radiant Energy System (CERES) Flight Model-5 (FM-5) instrument will fly on the NPOESS Preparatory Project (NPP) spacecraft, which has a launch-readiness date in June, 2010. This mission will continue the critical Earth Radiation Budget Climate Data Record (CDR) begun by the Earth Radiation Budget Experiment (ERBE) instruments in the mid 1980 s and continued by the CERES instruments currently flying on the EOS Terra and Aqua spacecraft. Ground calibrations have been completed for FM-5 and the instrument has been delivered for integration to the spacecraft Rigorous pre-launch ground calibration is performed on each CERES unit to achieve an accuracy goal of 1% for SW flux and 0.5% for outgoing LW flux. Any ground to flight or in-flight changes in radiometer response is monitored using a protocol employing both onboard and vicarious calibration sources and experiments. Recent studies of FM-1 through FM-4 data have shown that the SW response of space based broadband radiometers can change dramatically due to optical contamination. With these changes having most impact on optical response to blue-to UV radiance, where tungsten lamps are largely devoid of output, such changes are hard to monitor accurately using existing on-board sources. This paper outlines the lessons learned on the existing CERES sensors from 30+ years of flight experience and presents a radiometric protocol to be implemented on the FM-5 instrument to ensure that its performance exceeds the stated calibration and stability goals.

Design and implementation of a prototype data system for earth radiation budget, cloud, aerosol, and chemistry data

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

Baum, B.A.; Barkstrom, B.R.

1993-04-01

The Earth Observing System (EOS) will collect data from a large number of satellite-borne instruments, beginning later in this decade, to make data accessible to the scientific community, NASA will build an EOS Data and Information System (EOSDIS). As an initial effort to accelerate the development of EOSDIS and to gain experience with such an information system, NASA and other agencies are working on a prototype system called Version O (VO). This effort will provide improved access to pre-EOS earth science data throughout the early EOSDIS period. Based on recommendations from the EOSDIS Science Advisory Panel, EOSDIS will have severalmore » distributed active archive centers (DAACs). Each DAAC will specialize in particular data sets. This paper describes work at the NASA Langley Research Center's (LaRC) DAAC. The Version 0 Langley DAAC began archiving and distributing existing data sets pertaining to the earth's radiation budget, clouds, aerosols, and tropospheric chemistry in late 1992. The primary goals of the LaRC VO effort are the following: (1) Enhance scientific use of existing data; (2) Develop institutional expertise in maintaining and distributing data; (3) Use institutional capability for processing data from previous missions such as the Earth Radiation Budget Experiment and the Stratospheric Aerosol and Gas Experiment to prepare for processing future EOS satellite data; (4) Encourage cooperative interagency and international involvement with data sets and research; and (5) Incorporate technological hardware and software advances quickly.« less

Variability of Earth's radiation budget components during 2009 - 2015 from radiometer IKOR-M data

NASA Astrophysics Data System (ADS)

Cherviakov, Maksim

2016-04-01

This report describes a new «Meteor-M» satellite program which has been started in Russia. The first satellite of new generation "Meteor-M» № 1 was put into orbit in September, 2009. The radiometer IKOR-M - «The Measuring instrument of short-wave reflected radiation" was created in Saratov State University. It was installed on Russian hydrometeorological satellites «Meteor-M» № 1 and № 2. Radiometer IKOR-M designed for satellite monitoring of the outgoing reflected short-wave radiation, which is one of the components of Earth's radiation budget. Such information can be used in different models of long-term weather forecasts, in researches of climate change trends and also in calculation of absorbed solar radiation values and albedo of the Earth-atmosphere system. Satellite «Meteor-M» № 1 and № 2 are heliosynchronous that allows observing from North to South Poles. The basic products of data processing are given in the form of global maps of distribution outgoing short-wave radiation (OSR), albedo and absorbed solar radiation (ASR). Such maps were made for each month during observation period. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website (http://www.sgu.ru/structure/geographic/metclim/balans) as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October, 2009 to August, 2014 and second - from August, 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the «Meteor-M» № 1 measurements in August, 2014 show very good agreement with the fluxes determined from «Meteor-M» № 2. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation

Attitude analysis of the Earth Radiation Budget Satellite (ERBS) yaw turn anomaly

NASA Technical Reports Server (NTRS)

Kronenwetter, J.; Phenneger, M.; Weaver, William L.

1988-01-01

The July 2 Earth Radiation Budget Satellite (ERBS) hydrazine thruster-controlled yaw inversion maneuver resulted in a 2.1 deg/sec attitude spin. This mode continued for 150 minutes until the spacecraft was inertially despun using the hydrazine thrusters. The spacecraft remained in a low-rate Y-axis spin of .06 deg/sec for 3 hours until the B-DOT control mode was activated. After 5 hours in this mode, the spacecraft Y-axis was aligned to the orbit normal, and the spacecraft was commanded to the mission mode of attitude control. This work presents the experience of real-time attitude determination support following analysis using the playback telemetry tape recorded for 7 hours from the start of the attitude control anomaly.

Radiometer offsets and count conversion coefficients for the Earth Radiation Budget Experiment (ERBE) spacecraft for the years 1984, 1985, and 1986

NASA Technical Reports Server (NTRS)

Paden, Jack; Pandey, Dhirendra K.; Shivakumar, Netra D.; Stassi, Joseph C.; Wilson, Robert; Bolden, William; Thomas, Susan; Gibson, M. Alan

1991-01-01

A compendium is presented of the ground and inflight scanner and nonscanner offsets and count conversion (gain) coefficients used for the Earth Radiation Budget Experiment (ERBE) production processing of data from the ERBS, NOAA-9, and NOAA-10 satellites for the 1 Nov. 1984 to 31 Dec. 1986.

The measurement of the earth's radiation budget as a problem in information theory - A tool for the rational design of earth observing systems

NASA Technical Reports Server (NTRS)

Barkstrom, B. R.

1983-01-01

The measurement of the earth's radiation budget has been chosen to illustrate the technique of objective system design. The measurement process is an approximately linear transformation of the original field of radiant exitances, so that linear statistical techniques may be employed. The combination of variability, measurement strategy, and error propagation is presently made with the help of information theory, as suggested by Kondratyev et al. (1975) and Peckham (1974). Covariance matrices furnish the quantitative statement of field variability.

Extended Kalman filter for attitude estimation of the earth radiation budget satellite

NASA Technical Reports Server (NTRS)

Deutschmann, Julie; Bar-Itzhack, Itzhack Y.

1989-01-01

The design and testing of an Extended Kalman Filter (EKF) for ground attitude determination, misalignment estimation and sensor calibration of the Earth Radiation Budget Satellite (ERBS) are described. Attitude is represented by the quaternion of rotation and the attitude estimation error is defined as an additive error. Quaternion normalization is used for increasing the convergence rate and for minimizing the need for filter tuning. The development of the filter dynamic model, the gyro error model and the measurement models of the Sun sensors, the IR horizon scanner and the magnetometers which are used to generate vector measurements are also presented. The filter is applied to real data transmitted by ERBS sensors. Results are presented and analyzed and the EKF advantages as well as sensitivities are discussed. On the whole the filter meets the expected synergism, accuracy and robustness.

Passive exposure of Earth radiation budget experiment components LDEF experiment AO-147: Post-flight examinations and tests

NASA Technical Reports Server (NTRS)

Hickey, John R.

1991-01-01

The Passive Exposure of Earth Radiation Budget Experiment Components (PEERBEC) experiment of the Long Duration Exposure Facility (LDEF) mission was composed of sensors and components associated with the measurement of the earth radiation budget (ERB) from satellites. These components included the flight spare sensors from the ERB experiment which operated on Nimbus 6 and 7 satellites. The experiment components and materials as well as the pertinent background and ancillary information necessary for the understanding of the intended mission and the results are described. The extent and timing of the LDEF mission brought the exposure from solar minimum between cycles 21 and 22 through the solar maximum of cycle 22. The orbital decay, coupled with the events of solar maximum, caused the LDEF to be exposed to a broader range of space environmental effects than were anticipated. The mission spanned almost six years concurrent with the 12 year (to date) Nimbus 7 operations. Preliminary information is presented on the following: (1) the changes in transmittance experienced by the interference filters; (2) the results of retesting of the thermopile sensors, which appear to be relatively unaffected by the exposure; and (3) the results of the recalibration of the APEX cavity radiometer. The degradation and recovery of the filters of the Nimbus 7 ERB are also discussed relative to the apparent atomic oxygen cleaning which also applies to the LDEF.

The RAVAN CubeSat Mission: A Pathfinder for a New Measurement of Earth's Radiation Budget

NASA Astrophysics Data System (ADS)

Swartz, W.; Lorentz, S. R.; Huang, P. M.; Smith, A. W.; Deglau, D.; Reynolds, E.; Carvo, J.; Papadakis, S.; Wu, D. L.; Wiscombe, W. J.; Dyrud, L. P.

2016-12-01

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat is a pathfinder for a constellation to measure the Earth's radiation imbalance (ERI), which is the single most important quantity for predicting the course of climate change over the next century. RAVAN demonstrates a small, accurate radiometer that measures top-of-the-atmosphere Earth-leaving fluxes of total and solar-reflected radiation. Coupled with knowledge of the incoming radiation from the Sun, a constellation of such measurements would aim to determine ERI directly. Our objective with RAVAN is to establish that a compact radiometer that is absolutely calibrated to climate accuracy can be built and operated in space for low cost. The radiometer, hosted on a 3U CubeSat, relies on two key technologies. The first is the use of vertically aligned carbon nanotubes (VACNTs) as the radiometer absorber. VACNT forests are some of the blackest materials known and have an extremely flat spectral response over a wide wavelength range. The second key technology is a gallium fixed-point blackbody calibration source, embedded in RAVAN's sensor head contamination cover, that serves as a stable and repeatable reference to track the long-term degradation of the sensor. Absolute calibration is also maintained by regular solar and deep space views. We present the scientific motivation for the NASA-funded mission, design and characterization of the spacecraft, and mission operations concept. Pending a successful launch in fall 2016, we will also present the first results on-orbit. RAVAN will help enable the development of an Earth radiation budget constellation mission that can provide the measurements needed for superior predictions of future climate change.

WCRP surface radiation budget shortwave data product description, version 1.1

NASA Technical Reports Server (NTRS)

Whitlock, C. H.; Charlock, T. P.; Staylor, W. F.; Pinker, R. T.; Laszlo, I.; Dipasquale, R. C.; Ritchey, N. A.

1993-01-01

Shortwave radiative fluxes which reach the Earth's surface are key elements that influence both atmospheric and oceanic circulation. The World Climate Research Program has established the Surface Radiation Budget climatology project with the ultimate goal of determining the various components of the surface radiation budget from satellite data on a global scale. This report describes the first global product that is being produced and archived as part of that effort. The interested user can obtain the monthly global data sets free of charge using e-mail procedures.

Implications of the Observed Mesoscale Variations of Clouds for Earth's Radiation Budget

NASA Technical Reports Server (NTRS)

Rossow, William B.; Delo, Carl; Cairns, Brian; Hansen, James E. (Technical Monitor)

2001-01-01

The effect of small-spatial-scale cloud variations on radiative transfer in cloudy atmospheres currently receives a lot of research attention, but the available studies are not very clear about which spatial scales are important and report a very large range of estimates of the magnitude of the effects. Also, there have been no systematic investigations of how to measure and represent these cloud variations. We exploit the cloud climatology produced by the International Satellite Cloud Climatology Project (ISCCP) to: (1) define and test different methods of representing cloud variation statistics, (2) investigate the range of spatial scales that should be included, (3) characterize cloud variations over a range of space and time scales covering mesoscale (30 - 300 km, 3-12 hr) into part of the lower part of the synoptic scale (300 - 3000 km, 1-30 days), (4) obtain a climatology of the optical thickness, emissivity and cloud top temperature variability of clouds that can be used in weather and climate GCMS, together with the parameterization proposed by Cairns et al. (1999), to account for the effects of small-scale cloud variations on radiative fluxes, and (5) evaluate the effect of observed cloud variations on Earth's radiation budget. These results lead to the formulation of a revised conceptual model of clouds for use in radiative transfer calculations in GCMS. The complete variability climatology can be obtained from the ISCCP Web site at http://isccp.giss.nasa.gov.

Climate modeling. [for use in understanding earth's radiation budget

NASA Technical Reports Server (NTRS)

1978-01-01

The requirements for radiation measurements suitable for the understanding, improvement, and verification of models used in performing climate research are considered. Both zonal energy balance models and three dimensional general circulation models are considered, and certain problems are identified as common to all models. Areas of emphasis include regional energy balance observations, spectral band observations, cloud-radiation interaction, and the radiative properties of the earth's surface.

On the relationship of the earth radiation budget to the variability of atmospheric available potential and kinetic energies

NASA Technical Reports Server (NTRS)

Randel, David L.; Vonder Haar, Thomas H.

1990-01-01

The zonal and eddy kinetics energies and available potential energies are examined for both the Northern and the Southern Hemispheres, using a data set produced by 8 years of continuous simultaneous observations of the circulation parameters and measurements of the earth radiation budget (ERB) from the Nimbus-7 ERB experiment. The relationships between the seasonal cycles in ERB and those of the energetics are obtained, showing that the solar annual cycle accounts for most of the seasonal variability. It was found that the ERB midlatitude gradients of the net balance and the outgoing radiation lead the annual cycle of the energetics by 2-3 weeks.

Use of a GCM to Explore Sampling Issues in Connection with Satellite Remote Sensing of the Earth Radiation Budget

NASA Technical Reports Server (NTRS)

Fowler, Laura D.; Wielicki, Bruce A.; Randall, David A.; Branson, Mark D.; Gibson, Gary G.; Denn, Fredrick M.

2000-01-01

Collocated in time and space, top-of-the-atmosphere measurements of the Earth radiation budget (ERB) and cloudiness from passive scanning radiometers, and lidar- and radar-in-space measurements of multilayered cloud systems, are the required combination to improve our understanding of the role of clouds and radiation in climate. Experiments to fly multiple satellites "in formation" to measure simultaneously the radiative and optical properties of overlapping cloud systems are being designed. Because satellites carrying ERB experiments and satellites carrying lidars- or radars-in space have different orbital characteristics, the number of simultaneous measurements of radiation and clouds is reduced relative to the number of measurements made by each satellite independently. Monthly averaged coincident observations of radiation and cloudiness are biased when compared against more frequently sampled observations due, in particular, to the undersampling of their diurnal cycle, Using the Colorado State University General Circulation Model (CSU GCM), the goal of this study is to measure the impact of using simultaneous observations from the Earth Observing System (EOS) platform and companion satellites flying lidars or radars on monthly averaged diagnostics of longwave radiation, cloudiness, and its cloud optical properties. To do so, the hourly varying geographical distributions of coincident locations between the afternoon EOS (EOS-PM) orbit and the orbit of the ICESAT satellite set to fly at the altitude of 600 km, and between the EOS PM orbit and the orbits of the PICASSO satellite proposed to fly at the altitudes of 485 km (PICA485) or 705 km (PICA705), are simulated in the CSU GCM for a 60-month time period starting at the idealistic July 1, 2001, launch date. Monthly averaged diagnostics of the top-of-the-atmosphere, atmospheric, and surface longwave radiation budgets and clouds accumulated over grid boxes corresponding to satellite overpasses are compared against

Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results (Part I): Earths Radiation Budget

NASA Technical Reports Server (NTRS)

Holdaway, Daniel; Yang, Yuekui

2016-01-01

Satellites always sample the Earth-atmosphere system in a finite temporal resolution. This study investigates the effect of sampling frequency on the satellite-derived Earth radiation budget, with the Deep Space Climate Observatory (DSCOVR) as an example. The output from NASA's Goddard Earth Observing System Version 5 (GEOS-5) Nature Run is used as the truth. The Nature Run is a high spatial and temporal resolution atmospheric simulation spanning a two-year period. The effect of temporal resolution on potential DSCOVR observations is assessed by sampling the full Nature Run data with 1-h to 24-h frequencies. The uncertainty associated with a given sampling frequency is measured by computing means over daily, monthly, seasonal and annual intervals and determining the spread across different possible starting points. The skill with which a particular sampling frequency captures the structure of the full time series is measured using correlations and normalized errors. Results show that higher sampling frequency gives more information and less uncertainty in the derived radiation budget. A sampling frequency coarser than every 4 h results in significant error. Correlations between true and sampled time series also decrease more rapidly for a sampling frequency less than 4 h.

Some characteristic differences in the earth's radiation budget over land and ocean derived from the Nimbus-7 ERB experiment

NASA Technical Reports Server (NTRS)

Kyle, H. L.; Vasanth, K. L.

1986-01-01

Broad spectral band data derived from the Nimbus-7 Earth Radiation Budget experiment are analyzed for the top-of-the-atmosphere noon vs. midnight variations in the exitant longwave flux density, spectral variations in the regional albedos, and differences in land and ocean net radiation budgets. The data were studied for a year (June 1979 to May 1980) on a global scale and for five selected study areas. The annual global total, near-UV visible, and near-IR albedo values, obtained were 30.2, 34.6, and 25.9, respectively, with marked differences in behavior between oceanic and continental regions. Over the continents, clouds and snow sharply decreased the near-IR albedo. The over-the-continent noon-emitted flux density averages were 15-25 W/sq m larger than the midnight values, with large regional and seasonal variations. Over the oceans, the average noon and midnight outgoing longwave-flux densities were nearly identical, with regional aqnd seasonal differences of several watts per square meter.

Atlas of wide-field-of-view outgoing longwave radiation derived from Nimbus 6 Earth radiation budget data set, July 1975 to June 1978

NASA Technical Reports Server (NTRS)

Bess, T. Dale; Smith, G. Louis

1987-01-01

An atlas of monthly mean outgoing longwave radiation global contour maps and associated spherical harmonic coefficients is presented. The atlas contains 36 months of continuous data from July 1975 to June 1978. The data were derived from the first Earth radiation budget experiment, which was flown on the Nimbus-6 Sun-synchronous satellite in 1975. Only the wide-field-of-view longwave measurements are cataloged in this atlas. The contour maps along with the associated sets of spherical harmonic coefficients form a valuable data set for studying different aspects of our changing climate over monthly, annual, and interannual scales in the time domain, and over regional, zonal, and global scales in the spatial domain.

Our contaminated atmosphere: The danger of climate change, phases 1 and 2. [effect of atmospheric particulate matter on surface temperature and earth's radiation budget

NASA Technical Reports Server (NTRS)

Cimorelli, A. J.; House, F. B.

1974-01-01

The effects of increased concentrations of atmospheric particulate matter on average surface temperature and on the components of the earth's radiation budget are studied. An atmospheric model which couples particulate loading to surface temperature and to changes in the earth's radiation budget was used. A determination of the feasibility of using satellites to monitor the effect of increased atmospheric particulate concentrations is performed. It was found that: (1) a change in man-made particulate loading of a factor of 4 is sufficient to initiate an ice age; (2) variations in the global and hemispheric weighted averages of surface temperature, reflected radiant fluz and emitted radiant flux are nonlinear functions of particulate loading; and (3) a black satellite sphere meets the requirement of night time measurement sensitivity, but not the required day time sensitivity. A nonblack, spherical radiometer whose external optical properties are sensitive to either the reflected radiant fluz or the emitted radiant flux meets the observational sensitivity requirements.

Earth radiation balance and climate: Why the Moon is the wrong place to observe the Earth

NASA Astrophysics Data System (ADS)

Kandel, Robert S.

1994-06-01

Increasing 'greenhouse' gases in the Earth's atmosphere will perturb the Earth's radiation balance, forcing climate change over coming decades. Climate sensitivity depends critically on cloud-radiation feedback: its evaluation requires continual observation of changing patterns of Earth radiation balance and cloud cover. The Moon is the wrong place for such observations, with many disadvantages compared to an observation system combining platforms in low polar, intermediate-inclination and geostationary orbits. From the Moon, active observations are infeasible; thermal infrared observations require very large instruments to reach spatial resolutions obtained at much lower cost from geostationary or lower orbits. The Earth's polar zones are never well observed from the Moon; other zones are invisible more than half the time. The monthly illumination cycle leads to further bias in radiation budget determinations. The Earth will be a pretty sight from the Earth-side of the Moon, but serious Earth observations will be made elsewhere.

Evidence for Large Decadal Variability in the Tropical Mean Radiative Energy Budget

NASA Technical Reports Server (NTRS)

Wielicki, Bruce A.; Wong, Takmeng; Allan, Richard; Slingo, Anthony; Kiehl, Jeffrey T.; Soden, Brian J.; Gordon, C. T.; Miller, Alvin J.; Yang, Shi-Keng; Randall, David R.;

Atlas of wide-field-of-view outgoing longwave radiation derived from Nimbus 7 Earth radiation budget data set - November 1978 to October 1985

NASA Technical Reports Server (NTRS)

Bess, T. Dale; Smith, G. Louis

1987-01-01

An atlas of monthly mean outgoing longwave radiation global contour maps and associated spherical harmonic coefficients is presented. The atlas contains 84 months of continuous data from November 1978 to October 1985. The data were derived from the second Earth radiation budget experiment, which was flown on the Nimbus 7 Sun-synchronous satellite in 1978. This data set is a companion set and extension to a similar report of the Nimbus 6 satellite. Together these two reports give a data set covering a 10 year time period and will be very valuable in studying different aspects of our changing climate over monthly, annual, and interannual scales in the time domain and over regional, zonal, and global scales in the spatial domain.

Assessment of the global energy budget of Mars and comparison to the Earth

NASA Astrophysics Data System (ADS)

Madeleine, J.; Head, J. W.; Forget, F.; Wolff, M. J.

2012-12-01

The energy balance of a planet depends on its radiative environment and internal energy production. In the case of present-day Mars, the whole climate system is by far controlled by solar radiation rather than internal heat. Over the last hundreds of millions of years, changes in the orbital parameters and insolation pattern have induced various climatic excursions, during which the energy transfers within the atmosphere were different from today. On the longer term, i.e. over the last billions of years, the energy budget was even more different, as a result of the larger geothermal flux and heat provided by volcanic eruptions and impacts. Seeing the climate of Mars from an energy budget perspective provides a framework for understanding the key processes, as well as constraining climate models. The goal of this research is thus to characterize and analyze the energy budget of Mars. The first step, which is described in this communication, consists of quantifying the different components of the Mars radiation budget using the LMD (Laboratoire de Météorologie Dynamique) GCM (Global Climate Model). The LMD/GCM has been developed for more than 20 years and has now reached a level of detail that allows us to quantify the different contributions of CO2 gas, dust and clouds to the radiation budget. The general picture of the radiation budget as simulated by the GCM can be summarized as follows. First of all, the global-mean shortwave (SW) flux incident on the top of the Martian atmosphere is 148.5 W m-2. Whereas most of the incoming solar radiation is absorbed by atmospheric gases on Earth, on Mars most of the sunlight is absorbed by dust particles. Our simulations show that around 15% of the incoming solar radiation is absorbed by dust particles whereas 2.5% is reflected by them. Water-ice clouds also reflect around 1.5% of the solar radiation, which is much smaller than the amount of radiation reflected by clouds on Earth (around 20%). The Martian atmosphere is even

Surface radiation budget in the Clouds and the Earth's Radiant Energy System (CERES) effort and in the Global Energy and Water Cycle Experiment (GEWEX)

NASA Technical Reports Server (NTRS)

Charlock, Thomas P.; Smith, G. L.; Rose, Fred G.

1990-01-01

The surface radiation budget (SRB) and the atmospheric radiative flux divergence (ARD) are vital components of the weather and climate system. The importance of radiation in a complex international scientific endeavor, the GEWEX of the World Climate Research Programme is explained. The radiative transfer techniques and satellite instrumentation that will be used to retrieve the SRB and ARD later in this decade with the CERES are discussed; CERES is a component of the Earth Observing System satellite program. Examples of consistent SRB and ARD retrievals made with Nimbus-7 and International Satellite Cloud Climatology Project data from July 1983 are presented.

Clouds, surface temperature, and the tropical and subtropical radiation budget

NASA Technical Reports Server (NTRS)

Dhuria, Harbans L.; Kyle, H. Lee

1980-01-01

Solar energy drives both the Earth's climate and biosphere, but the absorbed energy is unevenly distributed over the Earth. The tropical regions receive excess energy which is then transported by atmospheric and ocean currents to the higher latitudes. All regions at a given latitude receive the same top of the atmosphere solar irradiance (insolation). However, the net radiation received from the Sun in the tropics and subtropics varies greatly from one region to another depending on local conditions. Over land, variations in surface albedo are important. Over both land and ocean, surface temperature, cloud amount, and cloud type are also important. The Nimbus-7 cloud and Earth radiation budget (ERB) data sets are used to examine the affect of these parameters.

Spatial autocorrelation of radiation measured by the Earth Radiation Budget Experiment: Scene inhomogeneity and reciprocity violation

NASA Technical Reports Server (NTRS)

Davies, Roger

1994-01-01

The spatial autocorrelation functions of broad-band longwave and shortwave radiances measured by the Earth Radiation Budget Experiment (ERBE) are analyzed as a function of view angle in an investigation of the general effects of scene inhomogeneity on radiation. For nadir views, the correlation distance of the autocorrelation function is about 900 km for longwave radiance and about 500 km for shortwave radiance, consistent with higher degrees of freedom in shortwave reflection. Both functions rise monotonically with view angle, but there is a substantial difference in the relative angular dependence of the shortwave and longwave functions, especially for view angles less than 50 deg. In this range, the increase with angle of the longwave functions is found to depend only on the expansion of pixel area with angle, whereas the shortwave functions show an additional dependence on angle that is attributed to the occlusion of inhomogeneities by cloud height variations. Beyond a view angle of about 50 deg, both longwave and shortwave functions appear to be affected by cloud sides. The shortwave autocorrelation functions do not satisfy the principle of directional reciprocity, thereby proving that the average scene is horizontally inhomogeneous over the scale of an ERBE pixel (1500 sq km). Coarse stratification of the measurements by cloud amount, however, indicates that the average cloud-free scene does satisfy directional reciprocity on this scale.

Radiometer offsets and count conversion coefficients for the Earth Radiation Budget Experiment (ERBE) spacecraft for the years 1987, 1988, and 1989

NASA Technical Reports Server (NTRS)

Paden, Jack; Pandey, Dhirendra K.; Stassi, Joseph C.; Wilson, Robert; Bolden, William; Thomas, Susan; Gibson, M. Alan

1993-01-01

This document contains a compendium of the ground and in-flight scanner and non-scanner offsets and count conversion (gain) coefficients used for the Earth Radiation Budget Experiment (ERBE) production processing of data from the ERBS satellite for the period from 1 January 1987 to 31 December 1989; for the NOAA-9 satellite, for the month of January 1987; and for the NOAA-10 satellite, for the period from 1 January 1987 to 31 May 1989.

First global WCRP shortwave surface radiation budget dataset

NASA Technical Reports Server (NTRS)

Whitlock, C. H.; Charlock, T. P.; Staylor, W. F.; Pinker, R. T.; Laszlo, I.; Ohmura, A.; Gilgen, H.; Konzelman, T.; DiPasquale, R. C.; Moats, C. D.

1995-01-01

Shortwave radiative fluxes that reach the Earth's surface are key factors that influence atmospheric and oceanic circulations as well as surface climate. Yet, information on these fluxes is meager. Surface site data are generally available from only a limited number of observing stations over land. Much less is known about the large-scale variability of the shortwave radiative fluxes over the oceans, which cover most of the globe. Recognizing the need to produce global-scale fields of such fluxes for use in climate research, the World Climate Research Program has initiated activities that led to the establishment of the Surface Radiation Budget Climatology Project with the ultimate goal to determine various components of the surface radiation budget from satellite data. In this paper, the first global products that resulted from this activity are described. Monthly and daily data on a 280-km grid scale are available. Samples of climate parameters obtainable from the dataset are presented. Emphasis is given to validation and limitations of the results. For most of the globe, satellite estimates have bias values between +/- 20 W/sq m and rms values are around 25 W/sq m. There are specific regions with much larger uncertainties however.

Explaining Earths Energy Budget: CERES-Based NASA Resources for K-12 Education and Public Outreach

NASA Technical Reports Server (NTRS)

Chambers, L. H.; Bethea, K.; Marvel, M. T.; Ruhlman, K.; LaPan, J.; Lewis, P.; Madigan, J.; Oostra, D.; Taylor, J.

2014-01-01

Among atmospheric scientists, the importance of the Earth radiation budget concept is well understood. Papers have addressed the topic for over 100 years, and the large Clouds and the Earth's Radiant Energy System (CERES) science team (among others), with its multiple on-orbit instruments, is working hard to quantify the details of its various parts. In education, Earth's energy budget is a concept that generally appears in middle school and Earth science curricula, but its treatment in textbooks leaves much to be desired. Students and the public hold many misconceptions, and very few people have an appreciation for the importance of this energy balance to the conditions on Earth. More importantly, few have a correct mental model that allows them to make predictions and understand the effect of changes such as increasing greenhouse gas concentrations. As an outreach element of the core CERES team at NASA Langley, a multi-disciplinary group of scientists, educators, graphic artists, writers, and web developers has been developing and refining graphics and resources to explain the Earth's Energy budget over the last few decades. Resources have developed through an iterative process involving ongoing use in front of a variety of audiences, including students and teachers from 3rd to 12th grade as well as public audiences.

Development of multi-sensor global cloud and radiance composites for earth radiation budget monitoring from DSCOVR

NASA Astrophysics Data System (ADS)

Khlopenkov, Konstantin; Duda, David; Thieman, Mandana; Minnis, Patrick; Su, Wenying; Bedka, Kristopher

2017-10-01

The Deep Space Climate Observatory (DSCOVR) enables analysis of the daytime Earth radiation budget via the onboard Earth Polychromatic Imaging Camera (EPIC) and National Institute of Standards and Technology Advanced Radiometer (NISTAR). Radiance observations and cloud property retrievals from low earth orbit and geostationary satellite imagers have to be co-located with EPIC pixels to provide scene identification in order to select anisotropic directional models needed to calculate shortwave and longwave fluxes. A new algorithm is proposed for optimal merging of selected radiances and cloud properties derived from multiple satellite imagers to obtain seamless global hourly composites at 5-km resolution. An aggregated rating is employed to incorporate several factors and to select the best observation at the time nearest to the EPIC measurement. Spatial accuracy is improved using inverse mapping with gradient search during reprojection and bicubic interpolation for pixel resampling. The composite data are subsequently remapped into EPIC-view domain by convolving composite pixels with the EPIC point spread function defined with a half-pixel accuracy. PSF-weighted average radiances and cloud properties are computed separately for each cloud phase. The algorithm has demonstrated contiguous global coverage for any requested time of day with a temporal lag of under 2 hours in over 95% of the globe.

Development of Multi-Sensor Global Cloud and Radiance Composites for Earth Radiation Budget Monitoring from DSCOVR

NASA Technical Reports Server (NTRS)

Khlopenkov, Konstantin; Duda, David; Thieman, Mandana; Minnis, Patrick; Su, Wenying; Bedka, Kristopher

2017-01-01

The Deep Space Climate Observatory (DSCOVR) enables analysis of the daytime Earth radiation budget via the onboard Earth Polychromatic Imaging Camera (EPIC) and National Institute of Standards and Technology Advanced Radiometer (NISTAR). Radiance observations and cloud property retrievals from low earth orbit and geostationary satellite imagers have to be co-located with EPIC pixels to provide scene identification in order to select anisotropic directional models needed to calculate shortwave and longwave fluxes. A new algorithm is proposed for optimal merging of selected radiances and cloud properties derived from multiple satellite imagers to obtain seamless global hourly composites at 5-kilometer resolution. An aggregated rating is employed to incorporate several factors and to select the best observation at the time nearest to the EPIC measurement. Spatial accuracy is improved using inverse mapping with gradient search during reprojection and bicubic interpolation for pixel resampling. The composite data are subsequently remapped into EPIC-view domain by convolving composite pixels with the EPIC point spread function (PSF) defined with a half-pixel accuracy. PSF-weighted average radiances and cloud properties are computed separately for each cloud phase. The algorithm has demonstrated contiguous global coverage for any requested time of day with a temporal lag of under 2 hours in over 95 percent of the globe.

Radiation Budget Instrument (RBI) for JPSS-2

NASA Technical Reports Server (NTRS)

Georgieva, Elena; Priestley, Kory; Dunn, Barry; Cageao, Richard; Barki, Anum; Osmundsen, Jim; Turczynski, Craig; Abedin, Nurul

2015-01-01

Radiation Budget Instrument (RBI) will be one of five instruments flying aboard the JPSS-2 spacecraft, a polar-orbiting sun-synchronous satellite in Low Earth Orbit. RBI is a passive remote sensing instrument that will follow the successful legacy of the Clouds and Earth's Radiant Energy System (CERES) instruments to make measurement of Earth's short and longwave radiation budget. The goal of RBI is to provide an independent measurement of the broadband reflected solar radiance and Earth's emitted thermal radiance by using three spectral bands (Shortwave, Longwave, and Total) that will have the same overlapped point spread function (PSF) footprint on Earth. To ensure precise NIST-traceable calibration in space the RBI sensor is designed to use a visible calibration target (VCT), a solar calibration target (SCT), and an infrared calibration target (ICT) containing phase change cells (PCC) to enable on-board temperature calibration. The VCT is a thermally controlled integrating sphere with space grade Spectralon covering the inner surface. Two sides of the sphere will have fiber-coupled laser diodes in the UV to IR wavelength region. An electrical substitution radiometer on the integrating sphere will monitor the long term stability of the sources and the possible degradation of the Spectralon in space. In addition the radiometric calibration operations will use the Spectralon diffusers of the SCT to provide accurate measurements of Solar degradation. All those stable on-orbit references will ensure that calibration stability is maintained over the RBI sensor lifetime. For the preflight calibration the RBI will view five calibration sources - two integrating spheres and three CrIS (Cross-track Infrared Sounder ) -like blackbodies whose outputs will be validated with NIST calibration approach. Thermopile are the selected detectors for the RBI. The sensor has a requirement to perform lunar calibration in addition to solar calibration in space in a way similar to CERES

Radiation budget measurement/model interface

NASA Technical Reports Server (NTRS)

Vonderhaar, T. H.; Ciesielski, P.; Randel, D.; Stevens, D.

1983-01-01

This final report includes research results from the period February, 1981 through November, 1982. Two new results combine to form the final portion of this work. They are the work by Hanna (1982) and Stevens to successfully test and demonstrate a low-order spectral climate model and the work by Ciesielski et al. (1983) to combine and test the new radiation budget results from NIMBUS-7 with earlier satellite measurements. Together, the two related activities set the stage for future research on radiation budget measurement/model interfacing. Such combination of results will lead to new applications of satellite data to climate problems. The objectives of this research under the present contract are therefore satisfied. Additional research reported herein includes the compilation and documentation of the radiation budget data set a Colorado State University and the definition of climate-related experiments suggested after lengthy analysis of the satellite radiation budget experiments.

Development and Implementation of a Comprehensive Radiometric Validation Protocol for the CERES Earth Radiation Budget Climate Record Sensors

NASA Technical Reports Server (NTRS)

Priestley, K. J.; Matthews, G.; Thomas, S.

2006-01-01

The CERES Flight Models 1 through 4 instruments were launched aboard NASA's Earth Observing System (EOS) Terra and Aqua Spacecraft into 705 Km sun-synchronous orbits with 10:30 a.m. and 1:30 p.m. equatorial crossing times. These instruments supplement measurements made by the CERES Proto Flight Model (PFM) instrument launched aboard NASA's Tropical Rainfall Measuring Mission (TRMM) into a 350 Km, 38-degree mid-inclined orbit. CERES Climate Data Records consist of geolocated and calibrated instantaneous filtered and unfiltered radiances through temporally and spatially averaged TOA, Surface and Atmospheric fluxes. CERES filtered radiance measurements cover three spectral bands including shortwave (0.3 to 5 microns), total (0.3 to 100 microns) and an atmospheric window channel (8 to 12 microns). The CERES Earth Radiation Budget measurements represent a new era in radiation climate data, realizing a factor of 2 to 4 improvement in calibration accuracy and stability over the previous ERBE climate records, while striving for the next goal of 0.3-percent per decade absolute stability. The current improvement is derived from two sources: the incorporation of lessons learned from the ERBE mission in the design of the CERES instruments and the development of a rigorous and comprehensive radiometric validation protocol consisting of individual studies covering different spatial, spectral and temporal time scales on data collected both pre and post launch. Once this ensemble of individual perspectives is collected and organized, a cohesive and highly rigorous picture of the overall end-to-end performance of the CERES instrument's and data processing algorithms may be clearly established. This approach has resulted in unprecedented levels of accuracy for radiation budget instruments and data products with calibration stability of better than 0.2-percent and calibration traceability from ground to flight of 0.25-percent. The current work summarizes the development, philosophy

Effect of cloud cover and surface type on earth's radiation budget derived from the first year of ERBE data

NASA Technical Reports Server (NTRS)

Gibson, G. G.; Denn, F. M.; Young, D. F.; Harrison, E. F.; Minnis, P.; Barkstrom, B. R.

1990-01-01

One year of ERBE data is analyzed for variations in outgoing LW and absorbed solar flux. Differences in land and ocean radiation budgets as well as differences between clear-sky and total scenes, including clouds, are studied. The variation of monthly average radiative parameters is examined for February 1985 through January 1986 for selected study regions and on zonal and global scales. ERBE results show significant seasonal variations in both outgoing LW and absorbed SW flux, and a pronounced difference between oceanic and continental surfaces. The main factors determining cloud radiative forcing in a given region are solar insolation, cloud amount, cloud type, and surface properties. The strongest effects of clouds are found in the midlatitude storm tracks over the oceans. Over much of the globe, LW warming is balanced by SW cooling. The annual-global average net cloud forcing shows that clouds have a net cooling effect on the earth for the year.

Radiation energy budget studies using collocated AVHRR and ERBE observations

NASA Technical Reports Server (NTRS)

Ackerman, Steven A.; Inoue, Toshiro

1994-01-01

Changes in the energy balance at the top of the atmosphere are specified as a function of atmospheric and surface properties using observations from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner. By collocating the observations from the two instruments, flown on NOAA-9, the authors take advantage of the remote-sensing capabilities of each instrument. The AVHRR spectral channels were selected based on regions that are strongly transparent to clear sky conditions and are therefore useful for characterizing both surface and cloud-top conditions. The ERBE instruments make broadband observations that are important for climate studies. The approach of collocating these observations in time and space is used to study the radiative energy budget of three geographic regions: oceanic, savanna, and desert.

Effects of cirrus composition on atmospheric radiation budgets

NASA Technical Reports Server (NTRS)

Kinne, Stefan; Liou, Kuo-Nan

1988-01-01

A radiative transfer model that can be used to determine the change in solar and infrared fluxes caused by variations in the composition of cirrus clouds was used to investigate the importance of particle size and shape on the radiation budget of the Earth-atmosphere system. Even though the cloud optical thickness dominates the radiative properties of ice clouds, the particle size and nonsphericity of ice crystals are also important in calculations of the transfer of near-IR solar wavelengths. Results show that, for a given optical thickness, ice clouds composed of larger particles would produce larger greenhouse effects than those composed of smaller particles. Moreover, spherical particles with equivalent surface areas, frequently used for ice crystal clouds, would lead to an overestimation of the greenhouse effect.

First global WCRP shortwave surface radiation budget dataset

NASA Technical Reports Server (NTRS)

Whitlock, C. H.; Charlock, T. P.; Staylor, W. F.; Pinker, R. T.; Laszlo, I.; Ohmura, A.; Gilgen, H.; Konzelman, T.; Dipasquale, R. C.; Moats, C. D.

1995-01-01

Shortwave radiative fluxes that reach the earth's surface are key factors that influence atmospheric and oceanic circulations as well as surface climate. Yet, information on these fluxes is meager. Surface site data are generally available from only a limited number of observing stations over land. Much less is known about the large-scale variability of the shortwave radiative fluxes over the oceans, which cover most of the globe. Recognizing the need to produce global-scale fields of such fluxes for use in climate research, the World Climate Research Program has initiated activities that led to the establishment of the Surface Radiation Budget Climatology Project with the ultimate goal to determine various components of the surface radiation budget from satellite data. In this paper, the first global products that resulted from this activity are described. Monthly and daily data on a 280-km grid scale are available. Samples of climate parameters obtainable from the dataset are presented. Emphasis is given to validation and limitations of the results. For most of the globe, satellite estimates have bias values between +/- 20 W/sq m and root mean square (rms) values are around 25 W/sq m. There are specific regions with much larger uncertainties however.

50th Anniversary of Radiation Budget Measurements from Satellites

NASA Astrophysics Data System (ADS)

Raschke, Ehrhard, ,, Dr.; Kinne, Stefan, ,, Dr.

2010-05-01

The "space race" between the USA and the Soviet Union supported rapid developments of instruments to measure properties of the atmosphere from satellite platforms. The satellite Explorer 7 (launch on 13 October 1959) was the first to carry sensors which were sensitive to the fluxes of solar (shortwave) and terrestrial (longwave) radiation leaving the Earth to space. Improved versions of those sensors and more complicated radiometers were flown on various operational and experimental satellites of the Nimbus, ESSA, TIROS, COSMOS, and NOAA series. There results, although often inherent to strong sampling insufficiencies, provided already a general picture on the spatial distribution and seasonal variability of radiation budget components at the Top of the Atmosphere, which finally could be refined with the more recent and more accurate and complete data sets of the experiments ERBE, CERES and ScRaB. Numerical analyses of climate data complemented such measurements to obtain a complete picture on the radiation budget at various levels within the atmosphere and at ground. These data is now used to validate the performance of climate models.

Annual Cycle of Cloud Forcing of Surface Radiation Budget

NASA Technical Reports Server (NTRS)

Wilber, Anne C.; Smith, G. Louis; Stackhouse, Paul W., Jr.; Gupta, Shashi K.

2006-01-01

The climate of the Earth is determined by its balance of radiation. The incoming and outgoing radiation fluxes are strongly modulated by clouds, which are not well understood. The Earth Radiation Budget Experiment (Barkstrom and Smith, 1986) provided data from which the effects of clouds on radiation at the top of the atmosphere (TOA) could be computed (Ramanathan, 1987). At TOA, clouds increase the reflected solar radiation, tending to cool the planet, and decrease the OLR, causing the planet to retain its heat (Ramanathan et al., 1989; Harrison et al., 1990). The effects of clouds on radiation fluxes are denoted cloud forcing. These shortwave and longwave forcings counter each other to various degrees, so that in the tropics the result is a near balance. Over mid and polar latitude oceans, cloud forcing at TOA results in large net loss of radiation. Here, there are large areas of stratus clouds and cloud systems associated with storms. These systems are sensitive to surface temperatures and vary strongly with the annual cycle. During winter, anticyclones form over the continents and move to the oceans during summer. This movement of major cloud systems causes large changes of surface radiation, which in turn drives the surface temperature and sensible and latent heat released to the atmosphere.

Zonal average earth radiation budget measurements from satellites for climate studies

NASA Technical Reports Server (NTRS)

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

1976-01-01

Data from 29 months of satellite radiation budget measurements, taken intermittently over the period 1964 through 1971, are composited into mean month, season and annual zonally averaged meridional profiles. Individual months, which comprise the 29 month set, were selected as representing the best available total flux data for compositing into large scale statistics for climate studies. A discussion of spatial resolution of the measurements along with an error analysis, including both the uncertainty and standard error of the mean, are presented.

Energy Budget: Earth's Most Important and Least Appreciated Planetary Attribute

NASA Technical Reports Server (NTRS)

Chambers, Lin; Bethea, Katie

2013-01-01

The energy budget involves more than one kind of energy. People can sense this energy in different ways, depending on what type of energy it is. We see visible light using our eyes. We feel infrared energy using our skin (such as around a campfire). We know some species of animals can see ultraviolet light and portions of the infrared spectrum. NASA satellites use instruments that can "see" different parts of the electromagnetic spectrum to observe various processes in the Earth system, including the energy budget. The Sun is a very hot ball of plasma emitting large amounts of energy. By the time it reaches Earth, this energy amounts to about 340 Watts for every square meter of Earth on average. That's almost 6 60-Watt light bulbs for every square meter of Earth! With all of that energy shining down on the Earth, how does our planet maintain a comfortable balance that allows a complex ecosystem, including humans, to thrive? The key thing to remember is the Sun - hot though it is - is a tiny part of Earth's environment. Earth's energy budget is a critical but little understood aspect of our planetary home. NASA is actively studying this important Earth system feature, and sharing data and knowledge about it with the education community.

Analysis of the Diurnal Cycle and Cloud Effects on the Surface Radiation Budget of the SURFRAD Network

NASA Astrophysics Data System (ADS)

Long, C. N.; Augustine, J. A.; McComiskey, A. C.

2017-12-01

The NOAA Earth Systems Research Laboratory (ESRL) Global Monitoring Division (GMD) operates a network of seven surface radiation budget sites (SURFRAD) across the continental United States. The SURFRAD network was established in 1993 with the primary objective to support climate research with accurate, continuous, long-term measurements of the surface radiation budget over the United States and is a major contributor to the WMO international Baseline Surface Radiation Network. The data from the SURFRAD sites have been used in many studies including trend analyses of surface solar brightening (Long et al, 2009; Augustine and Dutton, 2013; Gan et al., 2015). These studies have focused mostly on long term aggregate trends. Here we will present results of studies that take a closer look across the years of the cloud influence on the surface radiation budget components partitioned by seasonal and diurnal analyses, and using derived quantities now available from the SURFRAD data archive produced by the Radiative Flux Analysis value added processing. The results show distinct differences between the sites surface radiative energy budgets and cloud radiative effects due to their differing climates and latitudinal locations.

Thermal Orbital Environmental Parameter Study on the Propulsive Small Expendable Deployer System (ProSEDS) Using Earth Radiation Budget Experiment (ERBE) Data

NASA Technical Reports Server (NTRS)

Sharp, John R.; McConnaughey, Paul K. (Technical Monitor)

2002-01-01

The natural thermal environmental parameters used on the Space Station Program (SSP 30425) were generated by the Space Environmental Effects Branch at NASA's Marshall Space Flight Center (MSFC) utilizing extensive data from the Earth Radiation Budget Experiment (ERBE), a series of satellites which measured low earth orbit (LEO) albedo and outgoing long-wave radiation. Later, this temporal data was presented as a function of averaging times and orbital inclination for use by thermal engineers in NASA Technical Memorandum TM 4527. The data was not presented in a fashion readily usable by thermal engineering modeling tools and required knowledge of the thermal time constants and infrared versus solar spectrum sensitivity of the hardware being analyzed to be used properly. Another TM was recently issued as a guideline for utilizing these environments (NASA/TM-2001-211221) with more insight into the utilization by thermal analysts. This paper gives a top-level overview of the environmental parameters presented in the TM and a study of the effects of implementing these environments on an ongoing MSFC project, the Propulsive Small Expendable Deployer System (ProSEDS), compared to conventional orbital parameters that had been historically used.

Nimbus-7 Earth radiation budget calibration history. Part 1: The solar channels

NASA Technical Reports Server (NTRS)

Kyle, H. Lee; Hoyt, Douglas V.; Hickey, John R.; Maschhoff, Robert H.; Vallette, Brenda J.

1993-01-01

The Earth Radiation Budget (ERB) experiment on the Nimbus-7 satellite measured the total solar irradiance plus broadband spectral components on a nearly daily basis from 16 Nov. 1978, until 16 June 1992. Months of additional observations were taken in late 1992 and in 1993. The emphasis is on the electrically self calibrating cavity radiometer, channel 10c, which recorded accurate total solar irradiance measurements over the whole period. The spectral channels did not have inflight calibration adjustment capabilities. These channels can, with some additional corrections, be used for short-term studies (one or two solar rotations - 27 to 60 days), but not for long-term trend analysis. For channel 10c, changing radiometer pointing, the zero offsets, the stability of the gain, the temperature sensitivity, and the influences of other platform instruments are all examined and their effects on the measurements considered. Only the question of relative accuracy (not absolute) is examined. The final channel 10c product is also compared with solar measurements made by independent experiments on other satellites. The Nimbus experiment showed that the mean solar energy was about 0.1 percent (1.4 W/sqm) higher in the excited Sun years of 1979 and 1991 than in the quiet Sun years of 1985 and 1986. The error analysis indicated that the measured long-term trends may be as accurate as +/- 0.005 percent. The worse-case error estimate is +/- 0.03 percent.

Global Earth Outgoing Radiation From A Constellation Of Satellites: Proof-Of-Concept Study

NASA Astrophysics Data System (ADS)

Gristey, J. J.; Chiu, J. Y. C.; Gurney, R. J.; Han, S. C.; Morcrette, C. J.

2017-12-01

The flux of radiation exiting at the top of the atmosphere, referred to as Earth Outgoing Radiation (EOR), constitutes a vital component of the Earth's energy budget. Since EOR is inherently connected to the rapidly evolving scene from which the radiation originates and exhibits large regional variations, it is of paramount importance that we can monitor EOR at a sufficient frequency and spatial scale for weather and climate studies. Achieving these criteria remains challenging using traditional measurement techniques. However, explosive development in small satellite technology and sensor miniaturisation has paved a viable route for measurements to be made from a constellation of satellites in different orbits. This offers an exciting new opportunity to make observations of EOR with both global coverage and high temporal resolution for the first time. To assess the potential of the constellation approach for observing EOR we perform a series of observing system simulation experiments. We will outline a baseline constellation configuration capable of sampling the Earth with unprecedented temporal resolution. Using this configuration and a sophisticated deconvolution technique, we demonstrate how to recover synoptic-scale global EOR to the accuracy required to understand Earth's global energy budget. Finally, we will reveal the impact of various modifications to the constellation configuration and provide recommendations for the community.

The earth's radiation budget and its relation to atmospheric hydrology. I - Observations of the clear sky greenhouse effect. II - Observations of cloud effects

NASA Technical Reports Server (NTRS)

Stephens, Graeme L.; Greenwald, Thomas J.

1991-01-01

The clear-sky components of the earth's radiation budget (ERB), the relationship of these components to the sea surface temperature (SST), and microwave-derived water-vapor amount are analyzed in an observational study along with the relationship between the cloudy-sky components of ERB and space/time coincident observations of SST, microwave-derived cloud liquid water, and cloud cover. The purpose of the study is to use these observations for establishing an understanding of the couplings between radiation and the atmosphere that are important to understanding climate feedback. A strategy for studying the greenhouse effect of earth by analyzing the emitted clear-sky longwave flux over the ocean is proposed. It is concluded that the largest observed influence of clouds on ERB is more consistent with macrophysical properties of clouds as opposed to microphysical properties. The analysis for clouds and the greenhouse effect of clouds is compared quantitatively with the clear sky results. Land-ocean differences and tropical-midlatitude differences are shown and explained in terms of the cloud macrostructure.

Calculation of the static in-flight telescope-detector response by deconvolution applied to point-spread function for the geostationary earth radiation budget experiment.

PubMed

Matthews, Grant

2004-12-01

The Geostationary Earth Radiation Budget (GERB) experiment is a broadband satellite radiometer instrument program intended to resolve remaining uncertainties surrounding the effect of cloud radiative feedback on future climate change. By use of a custom-designed diffraction-aberration telescope model, the GERB detector spatial response is recovered by deconvolution applied to the ground calibration point-spread function (PSF) measurements. An ensemble of randomly generated white-noise test scenes, combined with the measured telescope transfer function results in the effect of noise on the deconvolution being significantly reduced. With the recovered detector response as a base, the same model is applied in construction of the predicted in-flight field-of-view response of each GERB pixel to both short- and long-wave Earth radiance. The results of this study can now be used to simulate and investigate the instantaneous sampling errors incurred by GERB. Also, the developed deconvolution method may be highly applicable in enhancing images or PSF data for any telescope system for which a wave-front error measurement is available.

Radiation budget changes with dry forest clearing in temperate Argentina.

PubMed

Houspanossian, Javier; Nosetto, Marcelo; Jobbágy, Esteban G

2013-04-01

Land cover changes may affect climate and the energy balance of the Earth through their influence on the greenhouse gas composition of the atmosphere (biogeochemical effects) but also through shifts in the physical properties of the land surface (biophysical effects). We explored how the radiation budget changes following the replacement of temperate dry forests by crops in central semiarid Argentina and quantified the biophysical radiative forcing of this transformation. For this purpose, we computed the albedo and surface temperature for a 7-year period (2003-2009) from MODIS imagery at 70 paired sites occupied by native forests and crops and calculated the radiation budget at the tropopause and surface levels using a columnar radiation model parameterized with satellite data. Mean annual black-sky albedo and diurnal surface temperature were 50% and 2.5 °C higher in croplands than in dry forests. These contrasts increased the outgoing shortwave energy flux at the top of the atmosphere in croplands by a quarter (58.4 vs. 45.9 W m(-2) ) which, together with a slight increase in the outgoing longwave flux, yielded a net cooling of -14 W m(-2) . This biophysical cooling effect would be equivalent to a reduction in atmospheric CO2 of 22 Mg C ha(-1) , which involves approximately a quarter to a half of the typical carbon emissions that accompany deforestation in these ecosystems. We showed that the replacement of dry forests by crops in central Argentina has strong biophysical effects on the energy budget which could counterbalance the biogeochemical effects of deforestation. Underestimating or ignoring these biophysical consequences of land-use changes on climate will certainly curtail the effectiveness of many warming mitigation actions, particularly in semiarid regions where high radiation load and smaller active carbon pools would increase the relative importance of biophysical forcing. © 2012 Blackwell Publishing Ltd.

Long-Term Validation and Variability of the Shortwave and Longwave Radiation Data of the GEWEX Surface Radiation Budget (SRB) Project

NASA Technical Reports Server (NTRS)

Zhang, Taiping; Stackhouse, Paul W., Jr.; Gupta, Shashi K.; Cox, Stephan J.; Mikovitz, Colleen; Hinkelman, Laura M.

2006-01-01

In this investigation, we make systematic Surface Radiation Budget-Baseline Surface Radiation Network (SRB-BSRN), Surface Radiation Data Centre (SRB-WRDC) and Surface Radiation Budget-Global Energy Balance Archive (SRB-GEBA) comparisons for both shortwave and longwave daily and monthly mean radiation fluxes at the Earth's surface. We first have an overview of all the comparable pairs of data in scatter or scatter density plots. Then we show the time series of the SRB data at grids in which there are ground sites where longterm records of data are available for comparison. An overall very good agreement between the SRB data and ground observations is found. To see the variability of the SRB data during the 21.5 years, we computed the global mean and its linear trend. No appreciable trend is detected at the 5% level. The empirical orthogonal functions (EOF) of the SRB deseasonalized shortwave downward flux are computed over the Pacific region, and the first EOF coefficient is found to be correlated with the ENSO Index at a high value of coefficient of 0.7083.

Dynamic Electrothermal Model of a Sputtered Thermopile Thermal Radiation Detector for Earth Radiation Budget Applications

NASA Technical Reports Server (NTRS)

Weckmann, Stephanie

1997-01-01

The Clouds and the Earth's Radiant Energy System (CERES) is a program sponsored by the National Aeronautics and Space Administration (NASA) aimed at evaluating the global energy balance. Current scanning radiometers used for CERES consist of thin-film thermistor bolometers viewing the Earth through a Cassegrain telescope. The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently studying a new sensor concept to replace the current bolometer: a thermopile thermal radiation detector. This next-generation detector would consist of a thermal sensor array made of thermocouple junction pairs, or thermopiles. The objective of the current research is to perform a thermal analysis of the thermopile. Numerical thermal models are particularly suited to solve problems for which temperature is the dominant mechanism of the operation of the device (through the thermoelectric effect), as well as for complex geometries composed of numerous different materials. Feasibility and design specifications are studied by developing a dynamic electrothermal model of the thermopile using the finite element method. A commercial finite element-modeling package, ALGOR, is used.

Improvement in Clouds and the Earth's Radiant Energy System/Surface and Atmosphere Radiation Budget Dust Aerosol Properties, Effects on Surface Validation of Clouds and Radiative Swath

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

Rutan, D.; Rose, F.; Charlock, T.P.

2005-03-18

Within the Clouds and the Earth's Radiant Energy System (CERES) science team (Wielicki et al. 1996), the Surface and Atmospheric Radiation Budget (SARB) group is tasked with calculating vertical profiles of heating rates, globally, and continuously, beneath CERES footprint observations of Top of Atmosphere (TOA) fluxes. This is accomplished using a fast radiative transfer code originally developed by Qiang Fu and Kuo-Nan Liou (Fu and Liou 1993) and subsequently highly modified by the SARB team. Details on the code and its inputs can be found in Kato et al. (2005) and Rose and Charlock (2002). Among the many required inputsmore » is characterization of the vertical column profile of aerosols beneath each footprint. To do this SARB combines aerosol optical depth information from the moderate-resolution imaging spectroradiometer (MODIS) instrument along with aerosol constituents specified by the Model for Atmosphere and Chemical Transport (MATCH) of Collins et al. (2001), and aerosol properties (e.g. single scatter albedo and asymmetry parameter) from Tegen and Lacis (1996) and OPAC (Hess et al. 1998). The publicly available files that include these flux profiles, called the Clouds and Radiative Swath (CRS) data product, available from the Langley Atmospheric Sciences Data Center (http://eosweb.larc.nasa.gov/). As various versions of the code are completed, publishable results are named ''Editions.'' After CRS Edition 2A was finalized it was found that dust aerosols were too absorptive. Dust aerosols have subsequently been modified using a new set of properties developed by Andy Lacis and results have been released in CRS Edition 2B. This paper discusses the effects of changing desert dust aerosol properties, which can be significant for the radiation budget in mid ocean, a few thousand kilometers from the source regions. Resulting changes are validated via comparison of surface observed fluxes from the Saudi Solar Village surface site (Myers et al. 1999), and the E

The Seasonal Cycle of the Radiation Budget and Cloud Radiative Effect in the Amazon Rainforest of Brazil

NASA Astrophysics Data System (ADS)

Collow, A.; Miller, M. A.

2015-12-01

The Amazon Rainforest of Brazil is a region with potential climate sensitivities, especially with ongoing land surface changes and biomass burning aerosols due to deforestation. Ubiquitous moisture in the area make clouds a common feature over the Amazon Rainforest and along with the influences from deforestation have a significant impact on the radiation budget. This region experiences a seasonal contrast in clouds, precipitation, and aerosols making it an ideal location to study the relationship between these variables and the radiation budget. An internationally sponsored campaign entitled GOAmazon2014/15 included a deployment of an Atmospheric Radiation Measurement (ARM) Mobile Facility, which collected comprehensive measurements using in situ and remote sensors. Observations of clouds, aerosols, and radiative fluxes from the first year of the deployment are analyzed in conjunction with top of the atmosphere (TOA) observations from the Clouds and the Earth's Radiant Energy System (CERES) and analyses from the newly released Modern Era Retrospective Analysis for Research and Applications Version-2 (MERRA-2). The combination of surface and TOA observations allows for the calculation of radiative flux divergence and cloud radiative effect (CRE) within the column, while the comparison to MERRA-2 enables the verification of a new reanalysis product and a view of the spatial variation of the radiation budget. Clouds are very reflective in the area, creating a cooling effect in the shortwave (SW) at the surface, with some seasonality present due to the reduction of optically thick clouds in the dry season. Clouds have little effect on the column itself in the SW due to the balance between the reflective and absorbing properties of the clouds with the majority of the impact on the atmosphere from clouds warming in the longwave. Influences of aerosols are seen in the dry season, and an increase in moisture above the Amazon River and its tributaries enhance the CRE.

Global Observations of Aerosols and Clouds from Combined Lidar and Passive Instruments to Improve Radiation Budget and Climate Studies

NASA Technical Reports Server (NTRS)

Winker, David M.

1999-01-01

Current uncertainties in the effects of clouds and aerosols on the Earth radiation budget limit our understanding of the climate system and the potential for global climate change. Pathfinder Instruments for Cloud and Aerosol Spaceborne Observations - Climatologie Etendue des Nuages et des Aerosols (PICASSO-CENA) is a recently approved satellite mission within NASA's Earth System Science Pathfinder (ESSP) program which will address these uncertainties with a unique suite of active and passive instruments. The Lidar In-space Technology Experiment (LITE) demonstrated the potential benefits of space lidar for studies of clouds and aerosols. PICASSO-CENA builds on this experience with a payload consisting of a two-wavelength polarization-sensitive lidar, an oxygen A-band spectrometer (ABS), an imaging infrared radiometer (IIR), and a wide field camera (WFC). Data from these instruments will be used to measure the vertical distributions of aerosols and clouds in the atmosphere, as well as optical and physical properties of aerosols and clouds which influence the Earth radiation budget. PICASSO-CENA will be flown in formation with the PM satellite of the NASA Earth Observing System (EOS) to provide a comprehensive suite of coincident measurements of atmospheric state, aerosol and cloud optical properties, and radiative fluxes. The mission will address critical uncertainties iin the direct radiative forcing of aerosols and clouds as well as aerosol influences on cloud radiative properties and cloud-climate radiation feedbacks. PICASSO-CENA is planned for a three year mission, with a launch in early 2003. PICASSO-CENA is being developed within the framework of a collaboration between NASA and CNES.

Constraints from Earth's heat budget on mantle dynamics

NASA Astrophysics Data System (ADS)

Kellogg, L. H.; Ferrachat, S.

2006-12-01

Recent years have seen an increase in the number of proposed models to explain Earth's mantle dynamics: while two end-members, pure layered convection with the upper and lower mantle convecting separately from each other, and pure, whole mantle convection, appear not to satisfy all the observations, several addition models have been proposed. These models include and attempt to characterize least one reservoir that is enriched in radiogenic elements relative to the mid-ocean ridge basalt (MORB) source, as is required to account for most current estimates of the Earth's heat budget. This reservoir would also be responsible for the geochemical signature in some ocean island basalts (OIBs) like Hawaii, but must be rarely sampled at the surface. Our current knowledge of the mass- and heat-budget for the bulk silicate Earth from geochemical, cosmochemical and geodynamical observations and constraints enables us to quantify the radiogenic heat enrichment required to balance the heat budget. Without assuming any particular model for the structure of the reservoir, we first determine the inherent trade-off between heat production rate and mass of the reservoir. Using these constraints, we then investigate the dynamical inferences of the heat budget, assuming that the additional heat is produced within a deep layer above the core-mantle boundary. We carry out dynamical models of layered convection using four different fixed reservoir volumes, corresponding to deep layers of thicknesses 150, 500 1000 and 1600 km, respectively, and including both temperature-dependent viscosity and an instrinsic viscosity jump between upper and lower mantle. We then assess the viability of these cases against 5 criteria: stability of the deep layer through time, topography of the interface, effective density profile, intrinsic chemical density and the heat flux at the CMB.

User's guide: Nimbus-7 Earth radiation budget narrow-field-of-view products. Scene radiance tape products, sorting into angular bins products, and maximum likelihood cloud estimation products

NASA Technical Reports Server (NTRS)

Kyle, H. Lee; Hucek, Richard R.; Groveman, Brian; Frey, Richard

1990-01-01

The archived Earth radiation budget (ERB) products produced from the Nimbus-7 ERB narrow field-of-view scanner are described. The principal products are broadband outgoing longwave radiation (4.5 to 50 microns), reflected solar radiation (0.2 to 4.8 microns), and the net radiation. Daily and monthly averages are presented on a fixed global equal area (500 sq km), grid for the period May 1979 to May 1980. Two independent algorithms are used to estimate the outgoing fluxes from the observed radiances. The algorithms are described and the results compared. The products are divided into three subsets: the Scene Radiance Tapes (SRT) contain the calibrated radiances; the Sorting into Angular Bins (SAB) tape contains the SAB produced shortwave, longwave, and net radiation products; and the Maximum Likelihood Cloud Estimation (MLCE) tapes contain the MLCE products. The tape formats are described in detail.

Comparison and testing of extended Kalman filters for attitude estimation of the Earth radiation budget satellite

NASA Technical Reports Server (NTRS)

Deutschmann, Julie; Bar-Itzhack, Itzhack Y.; Rokni, Mohammad

1990-01-01

The testing and comparison of two Extended Kalman Filters (EKFs) developed for the Earth Radiation Budget Satellite (ERBS) is described. One EKF updates the attitude quaternion using a four component additive error quaternion. This technique is compared to that of a second EKF, which uses a multiplicative error quaternion. A brief development of the multiplicative algorithm is included. The mathematical development of the additive EKF was presented in the 1989 Flight Mechanics/Estimation Theory Symposium along with some preliminary testing results using real spacecraft data. A summary of the additive EKF algorithm is included. The convergence properties, singularity problems, and normalization techniques of the two filters are addressed. Both filters are also compared to those from the ERBS operational ground support software, which uses a batch differential correction algorithm to estimate attitude and gyro biases. Sensitivity studies are performed on the estimation of sensor calibration states. The potential application of the EKF for real time and non-real time ground attitude determination and sensor calibration for future missions such as the Gamma Ray Observatory (GRO) and the Small Explorer Mission (SMEX) is also presented.

Evaluating the design of satellite scanning radiometers for earth radiation budget measurements with system simulations. Part 1: Instantaneous estimates

NASA Technical Reports Server (NTRS)

Stowe, Larry; Ardanuy, Philip; Hucek, Richard; Abel, Peter; Jacobowitz, Herbert

1991-01-01

A set of system simulations was performed to evaluate candidate scanner configurations to fly as a part of the Earth Radiation Budget Instrument (ERBI) on the polar platforms during the 1990's. The simulation is considered of instantaneous sampling (without diurnal averaging) of the longwave and shortwave fluxes at the top of the atmosphere (TOA). After measurement and subsequent inversion to the TOA, the measured fluxes were compared to the reference fluxes for 2.5 deg lat/long resolution targets. The reference fluxes at this resolution are obtained by integrating over the 25 x 25 = 625 grid elements in each target. The differences between each of these two resultant spatially averaged sets of target measurements (errors) are taken and then statistically summarized. Five instruments are considered: (1) the Conically Scanning Radiometer (CSR); (2) the ERBE Cross Track Scanner; (3) the Nimbus-7 Biaxial Scanner; (4) the Clouds and Earth's Radiant Energy System Instrument (CERES-1); and (5) the Active Cavity Array (ACA). Identical studies of instantaneous error were completed for many days, two seasons, and several satellite equator crossing longitudes. The longwave flux errors were found to have the same space and time characteristics as for the shortwave fluxes, but the errors are only about 25 pct. of the shortwave errors.

An Earth longwave radiation climate model

NASA Technical Reports Server (NTRS)

Yang, S. K.

1984-01-01

An Earth outgoing longwave radiation (OLWR) climate model was constructed for radiation budget study. Required information is provided by on empirical 100mb water vapor mixing ratio equation of the mixing ratio interpolation scheme. Cloud top temperature is adjusted so that the calculation would agree with NOAA scanning radiometer measurements. Both clear sky and cloudy sky cases are calculated and discussed for global average, zonal average and world-wide distributed cases. The results agree well with the satellite observations. The clear sky case shows that the OLWR field is highly modulated by water vapor, especially in the tropics. The strongest longitudinal variation occurs in the tropics. This variation can be mostly explained by the strong water vapor gradient. Although in the zonal average case the tropics have a minimum in OLWR, the minimum is essentially contributed by a few very low flux regions, such as the Amazon, Indonesian and the Congo.

Total solar irradiance values determined using Earth Radiation Budget Experiment (ERBE) radiometers

NASA Technical Reports Server (NTRS)

Lee, Robert B., III; Gibson, Michael A.; Natarajan, Sudha

1988-01-01

During the October 1984 through January 1988 period, the ERBE solar monitors on the NASA Earth Radiation Satellite and on the National Oceanic and Atmospheric Administration NOAA 9 and NOAA 10 spacecraft were used to obtain mean total solar irradiance values of 1365, 1365, and 1363 W/sq m, respectively. Secular variations in the solar irradiance have been observed, and they appear to be correlated with solar activity.

Developing an Earth system Inverse model for the Earth's energy and water budgets.

NASA Astrophysics Data System (ADS)

Haines, K.; Thomas, C.; Liu, C.; Allan, R. P.; Carneiro, D. M.

2017-12-01

The CONCEPT-Heat project aims at developing a consistent energy budget for the Earth system in order to better understand and quantify global change. We advocate a variational "Earth system inverse" solution as the best methodology to bring the necessary expertise from different disciplines together. L'Ecuyer et al (2015) and Rodell et al (2015) first used a variational approach to adjust multiple satellite data products for air-sea-land vertical fluxes of heat and freshwater, achieving closed budgets on a regional and global scale. However their treatment of horizontal energy and water redistribution and its uncertainties was limited. Following the recent work of Liu et al (2015, 2017) which used atmospheric reanalysis convergences to derive a new total surface heat flux product from top of atmosphere fluxes, we have revisited the variational budget approach introducing a more extensive analysis of the role of horizontal transports of heat and freshwater, using multiple atmospheric and ocean reanalysis products. We find considerable improvements in fluxes in regions such as the North Atlantic and Arctic, for example requiring higher atmospheric heat and water convergences over the Arctic than given by ERA-Interim, thereby allowing lower and more realistic oceanic transports. We explore using the variational uncertainty analysis to produce lower resolution corrections to higher resolution flux products and test these against in situ flux data. We also explore the covariance errors implied between component fluxes that are imposed by the regional budget constraints. Finally we propose this as a valuable methodology for developing consistent observational constraints on the energy and water budgets in climate models. We take a first look at the same regional budget quantities in CMIP5 models and consider the implications of the differences for the processes and biases active in the models. Many further avenues of investigation are possible focused on better valuing

Greater future global warming inferred from Earth's recent energy budget.

PubMed

Brown, Patrick T; Caldeira, Ken

2017-12-06

Climate models provide the principal means of projecting global warming over the remainder of the twenty-first century but modelled estimates of warming vary by a factor of approximately two even under the same radiative forcing scenarios. Across-model relationships between currently observable attributes of the climate system and the simulated magnitude of future warming have the potential to inform projections. Here we show that robust across-model relationships exist between the global spatial patterns of several fundamental attributes of Earth's top-of-atmosphere energy budget and the magnitude of projected global warming. When we constrain the model projections with observations, we obtain greater means and narrower ranges of future global warming across the major radiative forcing scenarios, in general. In particular, we find that the observationally informed warming projection for the end of the twenty-first century for the steepest radiative forcing scenario is about 15 per cent warmer (+0.5 degrees Celsius) with a reduction of about a third in the two-standard-deviation spread (-1.2 degrees Celsius) relative to the raw model projections reported by the Intergovernmental Panel on Climate Change. Our results suggest that achieving any given global temperature stabilization target will require steeper greenhouse gas emissions reductions than previously calculated.

Investigation of scene identification algorithms for radiation budget measurements

NASA Technical Reports Server (NTRS)

Diekmann, F. J.

1986-01-01

The computation of Earth radiation budget from satellite measurements requires the identification of the scene in order to select spectral factors and bidirectional models. A scene identification procedure is developed for AVHRR SW and LW data by using two radiative transfer models. These AVHRR GAC pixels are then attached to corresponding ERBE pixels and the results are sorted into scene identification probability matrices. These scene intercomparisons show that there generally is a higher tendency for underestimation of cloudiness over ocean at high cloud amounts, e.g., mostly cloudy instead of overcast, partly cloudy instead of mostly cloudy, for the ERBE relative to the AVHRR results. Reasons for this are explained. Preliminary estimates of the errors of exitances due to scene misidentification demonstrates the high dependency on the probability matrices. While the longwave error can generally be neglected the shortwave deviations have reached maximum values of more than 12% of the respective exitances.

Measurement of the Earth's Radiation Budget components from Russian satellites "Meteor-M" № 1 and "Meteor-M" № 2

NASA Astrophysics Data System (ADS)

Cherviakov, M.

2015-12-01

One of the foremost challenges to monitoring the climate system is the ability to make a precise measurement of Earth's radiation budget components from space. Thereupon a new "Meteor-M" satellite program has been started in Russia. The first satellite of new generation "Meteor-M" № 1 was put into orbit in September, 2009 and second satellite "Meteor-M" № 2 - in July, 2014. Some measurements results obtained by the nadir looking medium field of view radiometers IKOR-M which was installed on "Meteor-M" satellites are presented. These equipments were created in Saratov State University under the direction of Yu. A. Sklyarov for monitoring of outgoing shortwave radiation (OSR), albedo and absorbed solar radiation (ASR) at TOA. The basic products of data processing are given in the form of global maps of distribution OSR, albedo and ASR. Such maps were made for each month during observation period. Fig. 1 presents the map of global distribution of monthly averaged values of albedo in April, 2014. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October, 2009 to August, 2014 and second - from August, 2014 to the present. Therefore, there is a period when both radiometers work at the same time. TOA fluxes deduced from the "Meteor-M" № 1 measurements in August, 2014 show very good agreement with the fluxes determined from "Meteor-M" № 2. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It was assessed spatial and temporal variations of albedo and ASR over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the

Defining the minimum temporal and spatial scales available from a new 72-month Nimbus-7 Earth Radiation Budget climate data set

NASA Technical Reports Server (NTRS)

Randel, D. L.; Campbell, G. G.; Vonder Haar, T. H.; Smith, L.

1986-01-01

Scale factors and assumptions which were applied in calculations of global radiation budget parameters based on ERB data are discussed. The study was performed to examine the relationship between the composite global ERB map that can be generated every six days using all available data and the actual average global ERB. The wide field of view ERB instrument functioned for the first 19 months of the Nimbus-7 life, and furnished sufficient data for calculating actual ERB averages. The composite was most accurate in regions with the least variation in radiation budget.

Future Flight Opportunities and Calibration Protocols for CERES: Continuation of Observations in Support of the Long-Term Earth Radiation Budget Climate Data Record

NASA Technical Reports Server (NTRS)

Priestley, Kory J.; Smith, George L.

2010-01-01

The goal of the Clouds and the Earth s Radiant Energy System (CERES) project is to provide a long-term record of radiation budget at the top-of-atmosphere (TOA), within the atmosphere, and at the surface with consistent cloud and aerosol properties at climate accuracy. CERES consists of an integrated instrument-algorithm validation science team that provides development of higher-level products (Levels 1-3) and investigations. It involves a high level of data fusion, merging inputs from 25 unique input data sources to produce 18 CERES data products. Over 90% of the CERES data product volume involves two or more instruments. Continuation of the Earth Radiation Budget (ERB) Climate Data Record (CDR) has been identified as critical in the 2007 NRC Decadal Survey, the Global Climate Observing System WCRP report, and in an assessment titled Impacts of NPOESS Nunn-McCurdy Certification on Joint NASA-NOAA Climate Goals . Five CERES instruments have flown on three different spacecraft: TRMM, EOS-Terra and EOS-Aqua. In response, NASA, NOAA and NPOESS have agreed to fly the existing CERES Flight Model (FM-5) on the NPP spacecraft in 2011 and to procure an additional CERES Sensor with modest upgrades for flight on the JPSS C1 spacecraft in 2014, followed by a CERES follow-on sensor for flight in 2018. CERES is a scanning broadband radiometer that measures filtered radiance in the SW (0.3-5 m), total (TOT) (0.3-200 m) and WN (8-12 m) regions. Pre-launch calibration is performed on each Flight Model to meet accuracy requirements of 1% for SW and 0.5% for outgoing LW observations. Ground to flight or in-flight changes are monitored using protocols employing onboard and vicarious calibration sources. Studies of flight data show that SW response can change dramatically due to optical contamination. with greatest impact in blue-to UV radiance, where tungsten lamps are largely devoid of output. While science goals remain unchanged for ERB Climate Data Record, it is now understood

Satellite Remote Sensing of Fires, Smoke and Regional Radiative Energy Budgets

NASA Technical Reports Server (NTRS)

Christopher, Sundar A.; Wang, Min; Barbieri, Kristine; Welch, Ronald M.; Yang, Shi-Keng

1997-01-01

Using satellite imagery, more than five million square kilometers of the forest and cerrado regions over South America are extensively studied to monitor fires and smoke during the 1985 and 1986 biomass burning season. The results are characterized for four major eco-systems, namely: (1) Tropical Rain Forest (TRF), (2) Tropical Broadleaf Seasonal (TBS), (3) Mild/Warm/Hot Grass/Shrub (MGS), and (4) Savanna/Grass and Seasonal Woods (SGW). Using collocated measurements from the instantaneous scanner Earth Radiation Budget Experiment [ERBE) data, the direct regional radiative forcing of biomass burning aerosols are computed. The results show that more than 70% of the fires occur in the MGS and SGW eco-systems due to agricultural practices. The smoke generated from biomass burning has negative net radiative forcing values for all four major ecosystems within South America. The smoke found directly over the fires have mean net radiative forcing values ranging between -25.6 to -33.9 W/sq m for 1985 and between -12.9 to -40.8 W/sq m for 1986. These results confirm that the regional net radiative impact of biomass burning is one of cooling.

The Sun-earth Imbalance radiometer for a direct measurement of the net heating of the earth

NASA Astrophysics Data System (ADS)

Dewitte, Steven; Karatekin, Özgür; Chevalier, Andre; Clerbaux, Nicolas; Meftah, Mustapha; Irbah, Abdanour; Delabie, Tjorven

2015-04-01

It is accepted that the climate on earth is changing due to a radiative energy imbalance at the top of the atmosphere, up to now this radiation imbalance has not been measured directly. The measurement is challenging both in terms of space-time sampling of the radiative energy that is leaving the earth and in terms of accuracy. The incoming solar radiation and the outgoing terrestrial radiation are of nearly equal magnitude - of the order of 340 W/m² - resulting in a much smaller difference or imbalance of the order of 1 W/m². The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar and the outgoing terrestrial radiation with the same instrument. Based on our 30 year experience of measuring the Total Solar Irradiance with the Differential Absolute RADiometer (DIARAD) type of instrument and on our 10 year experience of measuring the Earth Radiation Budget with the Geostationary Earth Radiation Budget (GERB) instrument on Meteosat Second Generation, we propose an innovative constellation of Sun-earth IMBAlance (SIMBA) radiometer cubesats with the ultimate goal to measure the Sun-earth radiation imbalance. A first Simba In Orbit Demonstration satellite is scheduled for flight with QB50 in 2015. It is currently being developed as ESA's first cubesat through an ESA GSTP project. In this paper we will give an overview of the Simba science objectives and of the current satellite and payload development status.

Development of response models for the Earth Radiation Budget Experiment (ERBE) sensors. Part 2: Analysis of the ERBE integrating sphere ground calibration

NASA Technical Reports Server (NTRS)

Halyo, Nesim; Taylor, Deborah B.

1987-01-01

An explicit solution of the spectral radiance leaving an arbitrary point on the wall of a spherical cavity with diffuse reflectivity is obtained. The solution is applicable to spheres with an arbitrary number of openings of any size and shape, an arbitrary number of light sources with possible non-diffuse characteristics, a non-uniform sphere wall temperature distribution, non-uniform and non-diffuse sphere wall emissivity and non-uniform but diffuse sphere wall spectral reflectivity. A general measurement equation describing the output of a sensor with a given field of view, angular and spectral response measuring the sphere output is obtained. The results are applied to the Earth Radiation Budget Experiment (ERBE) integrating sphere. The sphere wall radiance uniformity, loading effects and non-uniform wall temperature effects are investigated. It is shown that using appropriate interpretation and processing, a high-accuracy short-wave calibration of the ERBE sensors can be achieved.

Development of response models for the Earth Radiation Budget Experiment (ERBE) sensors. Part 1: Dynamic models and computer simulations for the ERBE nonscanner, scanner and solar monitor sensors

NASA Technical Reports Server (NTRS)

Halyo, Nesim; Choi, Sang H.; Chrisman, Dan A., Jr.; Samms, Richard W.

1987-01-01

Dynamic models and computer simulations were developed for the radiometric sensors utilized in the Earth Radiation Budget Experiment (ERBE). The models were developed to understand performance, improve measurement accuracy by updating model parameters and provide the constants needed for the count conversion algorithms. Model simulations were compared with the sensor's actual responses demonstrated in the ground and inflight calibrations. The models consider thermal and radiative exchange effects, surface specularity, spectral dependence of a filter, radiative interactions among an enclosure's nodes, partial specular and diffuse enclosure surface characteristics and steady-state and transient sensor responses. Relatively few sensor nodes were chosen for the models since there is an accuracy tradeoff between increasing the number of nodes and approximating parameters such as the sensor's size, material properties, geometry, and enclosure surface characteristics. Given that the temperature gradients within a node and between nodes are small enough, approximating with only a few nodes does not jeopardize the accuracy required to perform the parameter estimates and error analyses.

The impact of Earth system feedbacks on carbon budgets and climate response.

PubMed

Lowe, Jason A; Bernie, Daniel

2018-05-13

A number of studies have examined the size of the allowable global cumulative carbon budget compatible with limiting twenty-first century global average temperature rise to below 2°C and below 1.5°C relative to pre-industrial levels. These estimates of cumulative emissions have a number of uncertainties including those associated with the climate sensitivity and the global carbon cycle. Although the IPCC fifth assessment report contained information on a range of Earth system feedbacks, such as carbon released by thawing of permafrost or methane production by wetlands as a result of climate change, the impact of many of these Earth system processes on the allowable carbon budgets remains to be quantified. Here, we make initial estimates to show that the combined impact from typically unrepresented Earth system processes may be important for the achievability of limiting warming to 1.5°C or 2°C above pre-industrial levels. The size of the effects range up to around a 350 GtCO 2 budget reduction for a 1.5°C warming limit and around a 500 GtCO 2 reduction for achieving a warming limit of 2°C. Median estimates for the extra Earth system forcing lead to around 100 GtCO 2 and 150 GtCO 2 , respectively, for the two warming limits. Our estimates are equivalent to several years of anthropogenic carbon dioxide emissions at present rates. In addition to the likely reduction of the allowable global carbon budgets, the extra feedbacks also bring forward the date at which a given warming threshold is likely to be exceeded for a particular emission pathway.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. © 2018 The Author(s).

The impact of Earth system feedbacks on carbon budgets and climate response

NASA Astrophysics Data System (ADS)

Lowe, Jason A.; Bernie, Daniel

2018-05-01

A number of studies have examined the size of the allowable global cumulative carbon budget compatible with limiting twenty-first century global average temperature rise to below 2°C and below 1.5°C relative to pre-industrial levels. These estimates of cumulative emissions have a number of uncertainties including those associated with the climate sensitivity and the global carbon cycle. Although the IPCC fifth assessment report contained information on a range of Earth system feedbacks, such as carbon released by thawing of permafrost or methane production by wetlands as a result of climate change, the impact of many of these Earth system processes on the allowable carbon budgets remains to be quantified. Here, we make initial estimates to show that the combined impact from typically unrepresented Earth system processes may be important for the achievability of limiting warming to 1.5°C or 2°C above pre-industrial levels. The size of the effects range up to around a 350 GtCO2 budget reduction for a 1.5°C warming limit and around a 500 GtCO2 reduction for achieving a warming limit of 2°C. Median estimates for the extra Earth system forcing lead to around 100 GtCO2 and 150 GtCO2, respectively, for the two warming limits. Our estimates are equivalent to several years of anthropogenic carbon dioxide emissions at present rates. In addition to the likely reduction of the allowable global carbon budgets, the extra feedbacks also bring forward the date at which a given warming threshold is likely to be exceeded for a particular emission pathway. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

Surface radiation budget for climate applications

NASA Technical Reports Server (NTRS)

Suttles, J. T. (Editor); Ohring, G. (Editor)

1986-01-01

The Surface Radiation Budget (SRB) consists of the upwelling and downwelling radiation fluxes at the surface, separately determined for the broadband shortwave (SW) (0 to 5 micron) and longwave (LW) (greater than 5 microns) spectral regions plus certain key parameters that control these fluxes, specifically, SW albedo, LW emissivity, and surface temperature. The uses and requirements for SRB data, critical assessment of current capabilities for producing these data, and directions for future research are presented.

Evaluating the design of an earth radiation budget instrument with system simulations. Part 2: Minimization of instantaneous sampling errors for CERES-I

NASA Technical Reports Server (NTRS)

Stowe, Larry; Hucek, Richard; Ardanuy, Philip; Joyce, Robert

1994-01-01

Much of the new record of broadband earth radiation budget satellite measurements to be obtained during the late 1990s and early twenty-first century will come from the dual-radiometer Clouds and Earth's Radiant Energy System Instrument (CERES-I) flown aboard sun-synchronous polar orbiters. Simulation studies conducted in this work for an early afternoon satellite orbit indicate that spatial root-mean-square (rms) sampling errors of instantaneous CERES-I shortwave flux estimates will range from about 8.5 to 14.0 W/m on a 2.5 deg latitude and longitude grid resolution. Rms errors in longwave flux estimates are only about 20% as large and range from 1.5 to 3.5 W/sq m. These results are based on an optimal cross-track scanner design that includes 50% footprint overlap to eliminate gaps in the top-of-the-atmosphere coverage, and a 'smallest' footprint size to increase the ratio in the number of observations lying within to the number of observations lying on grid area boundaries. Total instantaneous measurement error also depends on the variability of anisotropic reflectance and emission patterns and on retrieval methods used to generate target area fluxes. Three retrieval procedures from both CERES-I scanners (cross-track and rotating azimuth plane) are used. (1) The baseline Earth Radiaton Budget Experiment (ERBE) procedure, which assumes that errors due to the use of mean angular dependence models (ADMs) in the radiance-to-flux inversion process nearly cancel when averaged over grid areas. (2) To estimate N, instantaneous ADMs are estimated from the multiangular, collocated observations of the two scanners. These observed models replace the mean models in computation of satellite flux estimates. (3) The scene flux approach, conducts separate target-area retrievals for each ERBE scene category and combines their results using area weighting by scene type. The ERBE retrieval performs best when the simulated radiance field departs from the ERBE mean models by less than

Observations of the Earth's Radiation Budget in relation to atmospheric hydrology. 4: Atmospheric column radiative cooling over the world's oceans

NASA Technical Reports Server (NTRS)

Stephens, Graeme L.; Slingo, Anthony; Webb, Mark J.; Minnett, Peter J.; Daum, Peter H.; Kleinman, Lawrence; Wittmeyer, Ian; Randall, David A.

1994-01-01

This paper introduces a simple method for deriving climatological values of the longwave flux emitted from the clear sky atmosphere to the ice-free ocean surface. It is shown using both theory and data from simulations how the ratio of the surface to top-of-atmosphere (TOA) flux is a simple function of water vapor (W) and a validation of the simple relationship is presented based on a limited set of surface flux measurements. The rms difference between the retrieved surface fluxes and the simulated surface fluxes is approximately 6 W/sq m. The clear sky column cooling rate of the atmosphere is derived from the Earth Radiation Budget Experiment (ERBE) values of the clear sky TOA flux and the surface flux retrieved using Special Scanning Microwave Imager (SSM/I) measurements of w together with ERBE clear sky fluxes. The relationship between this column cooling rate, w, and the sea surface temperature (SST) is explored and it is shown how the cooling rate systematically increases as both w and SST increase. The uncertainty implied in these estmates of cooling are approximately +/- 0.2 K/d. The effects of clouds on this longwave cooling are also explored by placing bounds on the possible impact of clouds on the column cooling rate based on certain assumptions about the effect of clouds on the longwave flux to the surface. It is shown how the longwave effects of clouds in a moist atmosphere where the column water vapor exceeds approximately 30 kg/sq m may be estimated from presently available satellite data with an uncertainty estimated to be approximately 0.2 K/d. Based on an approach described in this paper, we show how clouds in these relatively moist regions decrease the column cooling by almost 50% of the clear sky values and the existence of significant longitudinal gradients in column radiative heating across the equatorial and subtropical Pacific Ocean.

3D modeling of satellite spectral images, radiation budget and energy budget of urban landscapes

NASA Astrophysics Data System (ADS)

Gastellu-Etchegorry, J. P.

2008-12-01

DART EB is a model that is being developed for simulating the 3D (3 dimensional) energy budget of urban and natural scenes, possibly with topography and atmosphere. It simulates all non radiative energy mechanisms (heat conduction, turbulent momentum and heat fluxes, water reservoir evolution, etc.). It uses DART model (Discrete Anisotropic Radiative Transfer) for simulating radiative mechanisms: 3D radiative budget of 3D scenes and their remote sensing images expressed in terms of reflectance or brightness temperature values, for any atmosphere, wavelength, sun/view direction, altitude and spatial resolution. It uses an innovative multispectral approach (ray tracing, exact kernel, discrete ordinate techniques) over the whole optical domain. This paper presents two major and recent improvements of DART for adapting it to urban canopies. (1) Simulation of the geometry and optical characteristics of urban elements (houses, etc.). (2) Modeling of thermal infrared emission by vegetation and urban elements. The new DART version was used in the context of the CAPITOUL project. For that, districts of the Toulouse urban data base (Autocad format) were translated into DART scenes. This allowed us to simulate visible, near infrared and thermal infrared satellite images of Toulouse districts. Moreover, the 3D radiation budget was used by DARTEB for simulating the time evolution of a number of geophysical quantities of various surface elements (roads, walls, roofs). Results were successfully compared with ground measurements of the CAPITOUL project.

Short Wave Part of Earth's Energy Budget at Top of Atmosphere During 2009-2017 from Radiometer IKOR-M Data

NASA Astrophysics Data System (ADS)

Cherviakov, M.; Spiryakhina, A.; Surkova, Y.; Kulkova, E.; Shishkina, E.

2017-12-01

This report describes Earth's energy budget IKOR-M satellite program which has been started in Russia. The first satellite "Meteor-M" No 1 of this project was put into orbit in 2009. The IKOR-M radiometer is a satellite instrument which can measure reflected shortwave radiation (0.3-4.0 µm). It was created in Saratov University and installed on Russian meteorological satellites "Meteor-M" No 1 and No 2. IKOR-M designed for satellite monitoring of the outgoing short-wave radiation at top-of-atmosphere (TOA), which is one of the components of Earth's energy budget. Such measurements can be used to derive albedo and absorbed solar radiation at TOA. The basic products of data processing are given in the form of global maps of distribution outgoing short-wave radiation, albedo and absorbed solar radiation (ASR). Such maps were made for each month during observation period. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website (www.sgu.ru/structure/geographic/metclim/balans) as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October 2009 to August 2014 and second - from August 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the "Meteor-M" No 1 measurements in August 2014 show very good agreement with the fluxes determined from "Meteor-M" No 2. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El Nino in the Pacific Ocean. During the radiometer operation, there were two significant El Nino events. Spatial-temporal distribution of the albedo in the equatorial part of the Pacific Ocean was analyzed. Region with high albedo values of 35-40 % is formed in the region 180E

Determination of Earth outgoing radiation using a constellation of satellites

NASA Astrophysics Data System (ADS)

Gristey, Jake; Chiu, Christine; Gurney, Robert; Han, Shin-Chan; Morcrette, Cyril

2017-04-01

The outgoing radiation fluxes at the top of the atmosphere, referred to as Earth outgoing radiation (EOR), constitute a vital component of the Earth's energy budget. This EOR exhibits strong diurnal signatures and is inherently connected to the rapidly evolving scene from which the radiation originates, so our ability to accurately monitor EOR with sufficient temporal resolution and spatial coverage is crucial for weather and climate studies. Despite vast improvements in satellite observations in recent decades, achieving these criteria remains challenging from current measurements. A technology revolution in small satellites and sensor miniaturisation has created a new and exciting opportunity for a novel, viable and sustainable observation strategy from a constellation of satellites, capable of providing both global coverage and high temporal resolution simultaneously. To explore the potential of a constellation approach for observing EOR we perform a series of theoretical simulation experiments. Using the results from these simulation experiments, we will demonstrate a baseline constellation configuration capable of accurately monitoring global EOR at unprecedented temporal resolution. We will also show whether it is possible to reveal synoptic scale, fast evolving phenomena by applying a deconvolution technique to the simulated measurements. The ability to observe and understand the relationship between these phenomena and changes in EOR is of fundamental importance in constraining future warming of our climate system.

The Near-Earth Space Radiation Environment

NASA Technical Reports Server (NTRS)

Xapsos, Michael

2008-01-01

This viewgraph presentation reviews the effects of the Near-Earth space radiation environment on NASA missions. Included in this presentation is a review of The Earth s Trapped Radiation Environment, Solar Particle Events, Galactic Cosmic Rays and Comparison to Accelerator Facilities.

High-frequency variations in Earth rotation and the planetary momentum budget

NASA Technical Reports Server (NTRS)

Rosen, Richard D.

1995-01-01

The major focus of the subject contract was on helping to resolve one of the more notable discrepancies still existing in the axial momentum budget of the solid Earth-atmosphere system, namely the disappearance of coherence between length-of-day (l.o.d.) and atmospheric angular momentum (AAM) at periods shorter than about a fortnight. Recognizing the importance of identifying the source of the high-frequency momentum budget anomaly, the scientific community organized two special measurement campaigns (SEARCH '92 and CONT '94) to obtain the best possible determinations of l.o.d. and AAM. An additional goal was to analyze newly developed estimates of the torques that transfer momentum between the atmosphere and its underlying surface to determine whether the ocean might be a reservoir of momentum on short time scales. Discrepancies between AAM and l.o.d. at sub-fortnightly periods have been attributed to either measurement errors in these quantities or the need to incorporate oceanic angular momentum into the planetary budget. Results from the SEARCH '92 and CONT '94 campaigns suggest that when special attention is paid to the quality of the measurements, better agreement between l.o.d. and AAM at high frequencies can be obtained. The mechanism most responsible for the high-frequency changes observed in AAM during these campaigns involves a direct coupling to the solid Earth, i.e, the mountain torque, thereby obviating a significant oceanic role.

Observing and Modeling Earth's Energy Flows

NASA Astrophysics Data System (ADS)

Stevens, Bjorn; Schwartz, Stephen E.

2012-07-01

This article reviews, from the authors' perspective, progress in observing and modeling energy flows in Earth's climate system. Emphasis is placed on the state of understanding of Earth's energy flows and their susceptibility to perturbations, with particular emphasis on the roles of clouds and aerosols. More accurate measurements of the total solar irradiance and the rate of change of ocean enthalpy help constrain individual components of the energy budget at the top of the atmosphere to within ±2 W m-2. The measurements demonstrate that Earth reflects substantially less solar radiation and emits more terrestrial radiation than was believed even a decade ago. Active remote sensing is helping to constrain the surface energy budget, but new estimates of downwelling surface irradiance that benefit from such methods are proving difficult to reconcile with existing precipitation climatologies. Overall, the energy budget at the surface is much more uncertain than at the top of the atmosphere. A decade of high-precision measurements of the energy budget at the top of the atmosphere is providing new opportunities to track Earth's energy flows on timescales ranging from days to years, and at very high spatial resolution. The measurements show that the principal limitation in the estimate of secular trends now lies in the natural variability of the Earth system itself. The forcing-feedback-response framework, which has developed to understand how changes in Earth's energy flows affect surface temperature, is reviewed in light of recent work that shows fast responses (adjustments) of the system are central to the definition of the effective forcing that results from a change in atmospheric composition. In many cases, the adjustment, rather than the characterization of the compositional perturbation (associated, for instance, with changing greenhouse gas concentrations, or aerosol burdens), limits accurate determination of the radiative forcing. Changes in clouds contribute

Constraining the Global, Cloud-Free Reflected Solar Radiation Flux (RSRF) with Earth Observing System (EOS) Instruments

NASA Technical Reports Server (NTRS)

Kahn, Ralph

1999-01-01

Variations in the top-of-atmosphere reflected solar radiation flux, and in the factors that determine its value, are among the most important diagnostic indicators of changes in Earth's energy balance. Data from the MISR (Multi-angle Imaging SpectroRadiometer), MODIS (Moderate-resolution Imaging Spectroradiometer), SAGE-3 (Stratospheric Aerosol and Gas Experiment), and CERES (Clouds and Earth's Radiant Energy System), all of which are spacecraft instruments scheduled for launch in 1999, will each constrain pieces of the RSRF budget. Prior to launch, we are performing studies to determine the sensitivity of these instruments to key factors that influence the cloud-free RSRF: aerosol optical depth, aerosol scattering properties, and surface visible bidirectional reflectance distribution function (BRDF). We are also assessing the ability of the aggregate of instruments to constrain the overall RSRF budget under natural conditions over the globe. Consider the MISR retrieval of aerosols: according to simulations over cloud-free, calm ocean, for pure particles with natural ranges of optical depth, particle size, and indices of refraction, MISR can retrieve column aerosol optical depth for all but the darkest particles, to an uncertainty of at most 0.05 or 20%, whichever is larger, even if the particle properties are poorly known. For one common particle type, soot, constraints on the optical depth over dark ocean are very poor. The simulated measurements also allow us to distinguish spherical from non-spherical particles, to separate two to four compositional groups based on indices of refraction, and to identify three to four distinct size groups between 0. 1 and 2.0 microns characteristic radius at most latitudes. Based on these results, we expect to distinguish air masses containing different aerosol types, routinely and globally, with multiangle remote sensing data. Such results far exceed current satellite aerosol retrieval capabilities, which provide only total

Nimbus-7 Earth Radiation Budjet compact solar data set user's guide

NASA Technical Reports Server (NTRS)

Kyle, H. Lee; Penn, Lanning M.; Hoyt, Douglas; Love, Douglas; Vemury, Sastri; Vallette, Brenda J.

1994-01-01

Nimbus-7 Earth Radiation Budget (ERB) solar measurements extend from November 16, 1978, to December 13, 1993, but with data gaps in 1992 and 1993. The measurements include the total solar irradiance plus six broadband spectral components. The Channel 10c total irradiance data appears very stable, and the calibration, well done. A number of characterization problems remain in the spectral measurements. In the original program, the solar and Earth flux measurements were intermixed and spread over about 170 computer tapes. For easier access, the solar data have been collected into two compact data sets. All of the data are collected into 14 Summary Solar Tapes (SST's). In addition, two Channel 10c Solar Tapes (CST's) give a separate listing of the stable total solar irradiance measurements. Channel 10c calibration and orbital irradiance values are given on separate PC disks. This document gives data descriptions and formats, together with quality control and calibration procedures.

Impact of decadal cloud variations on the Earth's energy budget

NASA Astrophysics Data System (ADS)

Zhou, Chen; Zelinka, Mark D.; Klein, Stephen A.

2016-12-01

Feedbacks of clouds on climate change strongly influence the magnitude of global warming. Cloud feedbacks, in turn, depend on the spatial patterns of surface warming, which vary on decadal timescales. Therefore, the magnitude of the decadal cloud feedback could deviate from the long-term cloud feedback. Here we present climate model simulations to show that the global mean cloud feedback in response to decadal temperature fluctuations varies dramatically due to time variations in the spatial pattern of sea surface temperature. We find that cloud anomalies associated with these patterns significantly modify the Earth's energy budget. Specifically, the decadal cloud feedback between the 1980s and 2000s is substantially more negative than the long-term cloud feedback. This is a result of cooling in tropical regions where air descends, relative to warming in tropical ascent regions, which strengthens low-level atmospheric stability. Under these conditions, low-level cloud cover and its reflection of solar radiation increase, despite an increase in global mean surface temperature. These results suggest that sea surface temperature pattern-induced low cloud anomalies could have contributed to the period of reduced warming between 1998 and 2013, and offer a physical explanation of why climate sensitivities estimated from recently observed trends are probably biased low.

Radiation Protection Quantities for Near Earth Environments

NASA Technical Reports Server (NTRS)

Clowdsley, Martha S.; Wilson, John W.; Kim, Myung-Hee; Anderson, Brooke M.; Nealy, John E.

2004-01-01

As humans travel beyond the protection of the Earth's magnetic field and mission durations grow, risk due to radiation exposure will increase and may become the limiting factor for such missions. Here, the dosimetric quantities recommended by the National Council on Radiation Protection and Measurements (NCRP) for the evaluation of health risk due to radiation exposure, effective dose and gray-equivalent to eyes, skin, and blood forming organs (BFO), are calculated for several near Earth environments. These radiation protection quantities are evaluated behind two different shielding materials, aluminum and polyethylene. Since exposure limits for missions beyond low Earth orbit (LEO) have not yet been defined, results are compared to limits recommended by the NCRP for LEO operations.

A radiation and energy budget algorithm for forest canopies

NASA Astrophysics Data System (ADS)

Tunick, A.

2006-01-01

Previously, it was shown that a one-dimensional, physics-based (conservation-law) computer model can provide a useful mathematical representation of the wind flow, temperatures, and turbulence inside and above a uniform forest stand. A key element of this calculation was a radiation and energy budget algorithm (implemented to predict the heat source). However, to keep the earlier publication brief, a full description of the radiation and energy budget algorithm was not given. Hence, this paper presents our equation set for calculating the incoming total radiation at the canopy top as well as the transmission, reflection, absorption, and emission of the solar flux through a forest stand. In addition, example model output is presented from three interesting numerical experiments, which were conducted to simulate the canopy microclimate for a forest stand that borders the Blossom Point Field Test Facility (located near La Plata, Maryland along the Potomac River). It is anticipated that the current numerical study will be useful to researchers and experimental planners who will be collecting acoustic and meteorological data at the Blossom Point Facility in the near future.

The earth's radiation budget and its relation to atmospheric hydrology. III - Comparison of observations over the oceans with a GCM

NASA Technical Reports Server (NTRS)

Stephens, Graeme L.; Randall, David A.; Wittmeyer, Ian L.; Dazlich, Donald A.; Tjemkes, Stephen

1993-01-01

The ability of the Colorado State University general circulation model (GCM) to simulate interactions between the hydrological cycle and the radiative processes on earth was examined by comparing various sensitivity relationships established by the model with those observed on earth, and the observed and calculated seasonal cycles of the greenhouse effect and cloud radiative forcing. Results showed that, although the GCM model used was able to simulate well some aspects of the observed sensitivities, there were many serious quantitative differences, including problems in the simulation of the column vapor in the tropics and an excessively strong clear-sky greenhouse effect in the mid-latitudes. These differences led to an underestimation by the model of the sensitivity of the clear-sky greenhouse to changes in sea surface temperature.

The 1985 Biomass Burning Season in South America: Satellite Remote Sensing of Fires, Smoke, and Regional Radiative Energy Budgets

NASA Technical Reports Server (NTRS)

Christopher, Sundar A.; Wang, Min; Berendes, Todd A.; Welch, Ronald M.; Yang, Shi-Keng

1998-01-01

Using satellite imagery, more than five million square kilometers of the forest and cerrado regions over South America are extensively studied to monitor fires and smoke during the 1985 biomass burning season. The results are characterized for four major ecosystems, namely: (1) tropical rain forest, (2) tropical broadleaf seasonal, (3) savannah/grass and seasonal woods (SGW), and (4) mild/warm/hot grass/shrub (MGS). The spatial and temporal distribution of fires are examined from two different methods using the multispectral Advanced Very High Resolution Radiometer Local Area Coverage data. Using collocated measurements from the instantaneous scanner Earth Radiation Budget Experiment data, the direct regional radiative forcing of biomass burning aerosols is computed. The results show that more than 70% of the fires occur in the MGS and SGW ecosystems due to agricultural practices. The smoke generated from biomass burning has negative instantaneous net radiative forcing values for all four major ecosystems within South America. The smoke found directly over the fires has mean net radiative forcing values ranging from -25.6 to -33.9 W m(exp -2). These results confirm that the regional net radiative impact of biomass burning is one of cooling. The spectral and broadband properties for clear-sky and smoke regions are also presented that could be used as input and/or validation for other studies attempting to model the impact of aerosols on the earth-atmosphere system. These results have important applications for future instruments from the Earth Observing System (EOS) program. Specifically, the combination of the Visible Infrared Scanner and Clouds and the Earth's Radiant Energy System (CERES) instruments from the Tropical Rainfall Measuring Mission and the combination of Moderate Resolution Imaging Spectrometer and CERES instruments from the EOS morning crossing mission could provide reliable estimates of the direct radiative forcing of aerosols on a global scale

Assessment of NASA GISS CMIP5 and Post-CMIP5 Simulated Clouds and TOA Radiation Budgets Using Satellite Observations. Part 2; TOA Radiation Budget and CREs

NASA Technical Reports Server (NTRS)

Stanfield, Ryan E.; Dong, Xiquan; Xi, Baike; Del Genio, Anthony D.; Minnis, Patrick; Doelling, David; Loeb, Norman

2014-01-01

In Part I of this study, the NASA GISS Coupled Model Intercomparison Project (CMIP5) and post-CMIP5 (herein called C5 and P5, respectively) simulated cloud properties were assessed utilizing multiple satellite observations, with a particular focus on the southern midlatitudes (SMLs). This study applies the knowledge gained from Part I of this series to evaluate the modeled TOA radiation budgets and cloud radiative effects (CREs) globally using CERES EBAF (CE) satellite observations and the impact of regional cloud properties and water vapor on the TOA radiation budgets. Comparisons revealed that the P5- and C5-simulated global means of clear-sky and all-sky outgoing longwave radiation (OLR) match well with CE observations, while biases are observed regionally. Negative biases are found in both P5- and C5-simulated clear-sky OLR. P5-simulated all-sky albedo slightly increased over the SMLs due to the increase in low-level cloud fraction from the new planetary boundary layer (PBL) scheme. Shortwave, longwave, and net CRE are quantitatively analyzed as well. Regions of strong large-scale atmospheric upwelling/downwelling motion are also defined to compare regional differences across multiple cloud and radiative variables. In general, the P5 and C5 simulations agree with the observations better over the downwelling regime than over the upwelling regime. Comparing the results herein with the cloud property comparisons presented in Part I, the modeled TOA radiation budgets and CREs agree well with the CE observations. These results, combined with results in Part I, have quantitatively estimated how much improvement is found in the P5-simulated cloud and radiative properties, particularly over the SMLs and tropics, due to the implementation of the new PBL and convection schemes.

A study of surface temperatures, clouds and net radiation

NASA Technical Reports Server (NTRS)

Dhuria, Harbans

1994-01-01

The study is continuing and it is focused on examining seasonal relationships between climate parameters such as the surface temperatures, the net radiation and cloud types and amount on a global basis for the period February 1985 to January 1987. The study consists of an analysis of the combined Earth Radiation Budget Experiment (ERBE) and International Satellite Cloud Climatology Program (ISCCP) products. The main emphasis is on obtaining the information about the interactions and relationships of Earth Radiation Budget parameters, cloud and temperature information. The purpose is to gain additional qualitative and quantitative insight into the cloud climate relationship.

Clouds and the Earth's Radiant Energy System (CERES)

NASA Technical Reports Server (NTRS)

Carman, Stephen L.; Cooper, John E.; Miller, James; Harrison, Edwin F.; Barkstrom, Bruce R.

1992-01-01

The CERES (Clouds and the Earth's Radiant Energy System) experiment will play a major role in NASA's multi-platform Earth Observing System (EOS) program to observe and study the global climate. The CERES instruments will provide EOS scientists with a consistent data base of accurately known fields of radiation and of clouds. CERES will investigate the important question of cloud forcing and its influence on the radiative energy flow through the Earth's atmosphere. The CERES instrument is an improved version of the ERBE (Earth Radiation Budget Experiment) broadband scanning radiometer flown by NASA from 1984 through 1989. This paper describes the science of CERES, presents an overview of the instrument preliminary design, and outlines the issues related to spacecraft pointing and attitude control.

An overview of results from the GEWEX radiation flux assessment

NASA Astrophysics Data System (ADS)

Raschke, E.; Stackhouse, P.; Kinne, S.; Contributors from Europe; the USA

2013-05-01

Multi-annual radiative flux averages of the International Cloud Climatology Project (ISCCP), of the GEWEX - Surface Radiation Budget Project (SRB) and of the Clouds and Earth Radiative Energy System (CERES) are compared and analyzed to characterize the Earth's radiative budget, assess differences and identify possible causes. These satellite based data-sets are also compared to results of a median model, which represents 20 climate models, that participated in the 4th IPCC assessment. Consistent distribution patterns and seasonal variations among the satellite data-sets demonstrate their scientific value, which would further increase if the datasets would be reanalyzed with more accurate and consistent ancillary data.

Assessment of NASA GISS CMIP5 and Post-CMIP5 Simulated Clouds and TOA Radiation Budgets Using Satellite Observations

NASA Astrophysics Data System (ADS)

Stanfield, R. E.; Dong, X.; Xi, B.; Kennedy, A. D.; Del Genio, A. D.; Minnis, P.; Loeb, N. G.; Doelling, D.

2013-05-01

Marine Boundary Layer (MBL) Clouds are an extremely important part of the climate system. Their treatment in climate models is a large source of uncertainty that will harm future projection of the Earth's climate. Zhang et al. (2005, CMIP3) compared the GCMs simulated cloud fractions (CF) with NASA CERES and ISCCP results and found that most GCMs underestimated mid-latitude MBL clouds but overestimated their optical depth. The underestimated CF and overestimated cloud optical thickness in the models offset each other when calculating TOA radiation budgets. Recent studies (Jiang et al. 2012; Stanfield et al. 2013; and Dolinar et al. 2013) have found there has not been much improvement from CMIP3 to CMIP5 for MBL clouds. Most GCMs still simulate fewer mid-latitude MBL clouds. In this study, we compare the NASA GISS CMIP5 and Post-CMIP5 results with NASA CERES cloud properties (SYN1deg) and TOA radiation budgets (EBAF), as well as CloudSat-CALIPSO cloud products. Special attention has been paid over the Southern mid-latitudes (~ 30-60 °S) where the total cloud fractions can reach up to 80-90% with MBL clouds being the dominant cloud type. Comparisons have shown that the globally averaged total CFs and TOA radiation budgets from CMIP5 agreed well with satellite observations, however, there are significant regional differences. For example, most CMIP5 models underestimated MBL clouds over the Southern mid-latitudes, including the GISS GCM, resulting in less reflected (or more absorbed) shortwave flux at TOA. The preliminary results from NASA GISS post-CMIP5 have made many improvements, and agree much better with satellite observations. These improvements are attributed to a new PBL parameterization, where more/less clouds can be simulated when the PBL gets deeper/shallower. This update has a large effect on radiation and clouds.

Impact of Radiatively Interactive Dust Aerosols on Dust Transport and Mobilization in the NASA Goddard Earth Observing System (GEOS-5) Earth Model

NASA Astrophysics Data System (ADS)

Colarco, P. R.; Rocha Lima, A.; Darmenov, A.; Bloecker, C.

2017-12-01

Mineral dust aerosols scatter and absorb solar and infrared radiation, impacting the energy budget of the Earth system which in turns feeds back on the dynamical processes responsible for mobilization of dust in the first place. In previous work with radiatively interactive aerosols in the NASA Goddard Earth Observing System global model (GEOS-5) we found a positive feedback between dust absorption and emissions. Emissions were the largest for the highest shortwave absorption considered, which additionally produced simulated dust transport in the best agreement with observations. The positive feedback found was in contrast to other modeling studies which instead found a negative feedback, where the impact of dust absorption was to stabilize the surface levels of the atmosphere and so reduce wind speeds. A key difference between our model and other models was that in GEOS-5 we simulated generally larger dust particles, with correspondingly larger infrared absorption that led to a pronounced difference in the diurnal cycle of dust emissions versus simulations where these long wave effects were not considered. In this paper we seek to resolve discrepancies between our previous simulations and those of other modeling groups. We revisit the question of dust radiative feedback on emissions with a recent version of the GEOS-5 system running at a higher spatial resolution and including updates to the parameterizations for dust mobilization, initial dust particle size distribution, loss processes, and radiative transfer, and identify key uncertainties that remain based on dust optical property assumptions.

A comparison of radiation budgets in the Fram Strait marginal ice zone

NASA Technical Reports Server (NTRS)

Francis, Jennifer A.; Katsaros, Kristina B.; Ackerman, Thomas P.; Lind, Richard J.; Davidson, Kenneth L.

1991-01-01

Results are presented from calculations of radiation budgets for the sea-ice and the open-water regimes in the marginal ice zone (MIZ) of the Fram Strait, from measurements of surface irradiances and meteorological conditions made during the 1984 Marginal Ice Zone Experiment. Simultaneous measurements on either side of the ice edge allowed a comparison of the open-water and the sea-ice environments. The results show significant differences between the radiation budgets of the two regimes in the MIZ. The open water absorbed twice as much radiation as did the ice, and the mean cooling rate of the atmosphere over water was approximately 15 percent larger than that over ice. Calculated fluxes and atmospheric cooling rates were found to compare well with available literature data.

Workshop Report on Managing Solar Radiation

NASA Technical Reports Server (NTRS)

Lane, Lee (Compiler); Caldeira, Ken (Compiler); Chatfield, Robert (Compiler); Langhoff, Stephanie (Compiler)

2007-01-01

The basic concept of managing Earth's radiation budget is to reduce the amount of incoming solar radiation absorbed by the Earth so as to counterbalance the heating of the Earth that would otherwise result from the accumulation of greenhouse gases. The workshop did not seek to decide whether or under what circumstances solar radiation management should be deployed or which strategies or technologies might be best, if it were deployed. Rather, the workshop focused on defining what kinds of information might be most valuable in allowing policy makers more knowledgeably to address the various options for solar radiation management.

Geostationary earth climate sensor: Scientific utility and feasibility, phase A

NASA Technical Reports Server (NTRS)

Campbell, G. Garrett; Vonderharr, T. H.; Evert, T.; Kidder, Stanley Q.; Purdom, James F. W.

1991-01-01

The possibility of accurate broad band radiation budget measurements from a GEO platform will provide a unique opportunity for viewing radiation processes in the atmosphere-ocean system. The CSU/TRW team has prepared a Phase 1 instrument design study demonstrating that measurements of radiation budget are practical from geosynchronous orbit with proven technology. This instrument concept is the Geostationary Earth Climate Sensor (GECS). A range of resolutions down to 20 km at the top of the atmosphere are possible, depending upon the scientific goals of the experiment. These tradeoffs of resolution and measurement repeat cycles are examined for scientific utility. The design of a flexible instrument is shown to be possible to meet the two goals: long-term, systematic monitoring of the diurnal cycles of radiation budget; and high time and space resolution studies of regional radiation features.

Measuring Earth's radiation imbalance with RAVAN: A CubeSat mission to measure the driver of global climate change

NASA Astrophysics Data System (ADS)

Swartz, W. H.; Dyrud, L. P.; Wiscombe, W. J.; Lorentz, S. R.; Papadakis, S.; Summers, R. A.; Smith, A. W.; Wu, D. L.; Deglau, D. M.; Arnold, S. P.

2013-12-01

The Earth radiation imbalance (ERI) is the single most important quantity for predicting the course of climate change over the next century. It is also the single most important metric for any geo-engineering scheme. We review the current scientific understanding of ERI and present a recently funded CubeSat mission, the Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN), that will demonstrate an affordable, accurate radiometer that directly measures Earth-leaving fluxes of total and solar-reflected radiation. Coupled with knowledge of the incoming radiation from the Sun, RAVAN directly gives ERI. The objective of RAVAN is to demonstrate that a compact spaceborne radiometer that is absolutely accurate to NIST-traceable standards can be built for low cost. The key technologies that enable a radiometer with all these attributes are: a gallium fixed-point blackbody as a built-in calibration source and a vertically aligned carbon nanotube (VACNT) absorber. VACNTs are the blackest known substance, making them ideal radiometer absorbers with order-of-magnitude improvements in spectral flatness and stability over the existing art. The Johns Hopkins University Applied Physics Laboratory heritage 3U Multi-Mission Nanosat will host RAVAN, providing the reliability, agility, and resources needed. RAVAN will pave the way for a constellation Earth radiation budget mission that can provide the measurements needed to enable vastly superior predictions of future climate change.

Giant radiating dyke swarms on Earth and Venus

NASA Technical Reports Server (NTRS)

Ernst, Richard E.; Head, James W.; Parfitt, Elisabeth; Wilson, Lionel; Grosfils, Eric

1993-01-01

On Earth, giant radiating dyke swarms are usually preserved as fan-shaped fragments which have been dismembered from their original configuration by subsequent plate tectonic rifting events. Analysis of the largest fragments and consideration of their original configuration has led to the idea that many swarms are plume related, and that dyke swarms radiate away from plume centers. Magellan radar data reveal abundant intact giant radiating swarms on Venus which are similar in scale and pattern to those on Earth. The absence of intense weathering and plate tectonic processes on Venus accounts for the preservation of the primary radiating patterns. It is characteristic of both Earth and Venus that giant radiating dikes are emplaced laterally for distances of at least 2000 km away from plume centers. At distances beyond the influence of the plume on both Earth and Venus, the radiating dyke pattern is often swept into a linear pattern aligned with the regional stress field. There is tremendous potential synergism between the characterization and analysis of terrestrial dyke swarms (where significant erosion has revealed their structure and emplacement directions at depth) and the giant swarms of Venus (where the complete circumferential structure is preserved, and the surface fracture systems above near surface dikes and the nature of the central source regions are revealed). In this study, we report on the characteristics of radial dyke swarms on Earth and Venus and draw some preliminary comparisons from the two perspectives. In summary, on both planets there is evidence for plume-related magmatic centers associated with vertical and lateral injection of magma over considerable distances (up to at least 2000 km). The abundance of very broadly radiating swarms on Venus supports the notion that the swarms on Earth were radiating over broad sectors at the time of intrusion but were dissected by later events. The Venus data show that a swarm can change from radiating

Nowcast and Short-Term Forecast of Solar Radiation for Photovoltaic power and Solar thermal using 3rd generation geostationary satellite.

NASA Astrophysics Data System (ADS)

Takenaka, H.; Teruyuki, N.; Nakajima, T. Y.; Higurashi, A.; Hashimoto, M.; Suzuki, K.; Uchida, J.; Nagao, T. M.; Shi, C.; Inoue, T.

2017-12-01

It is important to estimate the earth's radiation budget accurately for understanding of climate. Clouds can cool the Earth by reflecting solar radiation but also maintain warmth by absorbing and emitting terrestrial radiation. similarly aerosols also have an effect on radiation budget by absorption and scattering of Solar radiation. In this study, we developed the high speed and accurate algorithm for shortwave (SW) radiation budget and it's applied to geostationary satellite for rapid analysis. It enabled highly accurate monitoring of solar radiation and photo voltaic (PV) power generation. Next step, we try to update the algorithm for retrieval of Aerosols and Clouds. It indicates the accurate atmospheric parameters for estimation of solar radiation. (This research was supported in part by CREST/EMS).

Impact of Asian Dust on Global Surface Air Quality and Radiation Budget

NASA Technical Reports Server (NTRS)

Chin, Mian; Diehl, Thomas; Yu, Hongbin; Ginoux, Paul

2006-01-01

Dust originating from Asian deserts and desertification areas can be transported regionally and globally to affect surface air quality, visibility, and radiation budget not only at immediate downwind locations (e.g., eastern Asia) but also regions far away from the sources (e.g., North America). Deposition of Asian dust to the North Pacific Ocean basin influences the ocean productivity. In this study, we will use the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model, remote sensing data form satellite and from the ground-based network, and in-situ data from aircraft and surface observations to address the following questions: - What are the effects of Asian dust on the surface air quality and visibility over Asia and North America? - What are the seasonal and spatial variations of dust deposition to the North Pacific Ocean? How does the Asian dust affect surface radiation budget?

Evaluation and Improvement of Earth Radiation Budget Data Sets

NASA Technical Reports Server (NTRS)

Haeffelin, Martial P. A.

2001-01-01

The tasks performed during this grant are as follows: (1) Advanced scan patterns for enhanced spatial and angular sampling of ground targets; (2) Inter-calibration of polar orbiter in low Earth orbits (LEO) and geostationary (GEO) broadband radiance measurements; (3) Synergism between CERES on TRMM and Terra; (4) Improved surface solar irradiance measurements; (5) SW flux observations from Ultra Long Duration Balloons at 35 km altitude; (6) Nighttime cloud property retrieval algorithm; (7) Retrievals of overlapped and mixed-phase clouds.

The earth's trapped radiation belts

NASA Technical Reports Server (NTRS)

Noll, R. B.; Mcelroy, M. B.

1975-01-01

The near-earth charged particle environment is discussed in terms of spacecraft design criteria. Models are presented of the trapped radiation belts and based on in-situ data obtained from spacecraft.

Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

PubMed

Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

2014-03-20

Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt.

Theoretical and Observational Determination of Global and Regional Radiation Budget, Forcing and Feedbacks at the Top-of-Atmosphere and Surface

NASA Technical Reports Server (NTRS)

Loeb, Norman G.

2004-01-01

Report consists of: 1. List of accomplishments 2. List of publications 3. Abstracts of published or submitted papers and 4. Subject invention disclosure. The accomplishments of the grant listed are: 1. Improved the third-order turbulence closure in cloud resolving models to remove the liquid water oscillation. 2. Used the University of California-Los Angeles (UCLA) large-eddy simulation (LES) model to provide data for radiation transfer testing. 3. Revised shortwave k-distribution models based on HITRAN 2000. 4. Developed a gamma-weighted two-stream radiative transfer model for radiation budget estimate applications. 5. Estimated the effect of spherical geometry to the earth radiation budget. 6. Estimated top-of-atmosphere irradiance over snow and sea ice surfaces. 7. Estimated the aerosol direct radiative effect at the top of the atmosphere. 8. Estimated the top-of-atmosphere reflectance of the clear-sky molecular atmosphere over ocean. 9. Developed and validated new set of Angular Distribution Models for the CERES TRMM satellite instrument (tropical) 10. Developed and validated new set of Angular Distribution Models for the CERES Terra satellite instrument (global) 11. Quantified the top-of-atmosphere direct radiative effect of aerosols over global oceans from merged CERES and MODIS observations 12 Clarified the definition of TOA flux reference level for radiation budget studies 13. Developed new algorithm for unfaltering CERES measured radiances 14. Used multiangle POLDER measurements to produce narrowband angular distribution models and examine the effect of scene identification errors on TOA albedo estimates 15. Developed and validated a novel algorithm called the Multidirectional Reflectance Matching (MRM) model for inferring TOA albedos from ice clouds using multi-angle satellite measurements. 16. Developed and validated a novel algorithm called the Multidirectional Polarized Reflectance Matching (MPRM) model for inferring particle shapes from ice clouds

Near-Earth Space Radiation Models

NASA Technical Reports Server (NTRS)

Xapsos, Michael A.; O'Neill, Patrick M.; O'Brien, T. Paul

2012-01-01

Review of models of the near-Earth space radiation environment is presented, including recent developments in trapped proton and electron, galactic cosmic ray and solar particle event models geared toward spacecraft electronics applications.

Radiation Budget Profiles measured through the Atmosphere with a Return Glider Radiosonde

NASA Astrophysics Data System (ADS)

Philipona, R.; Kraeuchi, A.; Kivi, R.

2015-12-01

Very promising radiation budget profile measurements through the atmosphere were made in 2011 with a balloon borne short- and longwave net radiometer. New and improved radiation sensors from Kipp&Zonen are now used in a glider aircraft together with a standard Swiss radiosonde from Meteolabor AG. This new return glider radiosonde (RG-R), is lifted up with double balloon technique to prevent pendulum motion and to keep the radiation instruments as horizontal as possible during the ascent measuring phase. The RG-R is equipped with a release mechanism and an autopilot that flies the glider radiosonde back to the launch site, or to a predefined open space, where it releases a parachute for landing once it is 100 meter above ground. The RG-R was successfully tested and deployed for tropospheric and stratospheric radiation measurements up to 30 hPa (24 km altitude) at the GRUAN sites Payerne (Switzerland) and Sodankylä (Finland). Radiation profiles and the radiation budget through the atmosphere during different daytimes and under cloud-free and cloudy situations will be shown in relation to temperature and humidity at the surface and in the atmosphere. The RG-R flight characteristics and new measurement possibilities will also be discussed.

Dynamics of the Earth's Radiation Belts and Inner Magnetosphere

NASA Astrophysics Data System (ADS)

Schultz, Colin

2013-12-01

Trapped by Earth's magnetic field far above the planet's surface, the energetic particles that fill the radiation belts are a sign of the Sun's influence and a threat to our technological future. In the AGU monograph Dynamics of the Earth's Radiation Belts and Inner Magnetosphere, editors Danny Summers, Ian R. Mann, Daniel N. Baker, and Michael Schulz explore the inner workings of the magnetosphere. The book reviews current knowledge of the magnetosphere and recent research results and sets the stage for the work currently being done by NASA's Van Allen Probes (formerly known as the Radiation Belt Storm Probes). In this interview, Eos talks to Summers about magnetospheric research, whistler mode waves, solar storms, and the effects of the radiation belts on Earth.

Science and Technology Text Mining: Near-Earth Space

DTIC Science & Technology

2003-07-21

TRANSFER; 177SATELLITE IMAGES; 175 SPATIAL RESOLUTION ; 174 SEA ICE; 166 SYSTEM GPS; 166 TOPEX POSEIDON; 165 SATELLITE MEASUREMENTS; 163 RADIATION BUDGET...1073 ICE; 1065 SATELLITES; 1062 PAPER; 1009 EARTH; 1008 RESOLUTION ; 1000 MODELS; 962 RADIATION; 943 DERIVED; 938 OCEAN; 928 CURRENT; 925 SPATIAL ; 899...PARAMETERS; 729 TECHNIQUE; 714 OPTICAL; 714 SPACECRAFT; 711 DEGREE; 702 TRANSMISSION; 696 LARGE; 693 TEST; 686 NUMBER; 671 EFFECTS ; 662 SPECTRAL ; 661

Assessing surface albedo change and its induced radiation budget under rapid urbanization with Landsat and GLASS data

NASA Astrophysics Data System (ADS)

Hu, Yonghong; Jia, Gensuo; Pohl, Christine; Zhang, Xiaoxuan; van Genderen, John

2016-02-01

Radiative forcing (RF) induced by land use (mainly surface albedo) change is still not well understood in climate change science, especially the effects of changes in urban albedo due to rapid urbanization on the urban radiation budget. In this study, a modified RF derivation approach based on Landsat images was used to quantify changes in the solar radiation budget induced by variations in surface albedo in Beijing from 2001 to 2009. Field radiation records from a Beijing meteorological station were used to identify changes in RF at the local level. There has been rapid urban expansion over the last decade, with the urban land area increasing at about 3.3 % annually from 2001 to 2009. This has modified three-dimensional urban surface properties, resulting in lower albedo due to complex building configurations of urban centers and higher albedo on flat surfaces of suburban areas and cropland. There was greater solar radiation (6.93 × 108 W) in the urban center in 2009 than in 2001. However, large cropland and urban fringe areas caused less solar radiation absorption. RF increased with distance from the urban center (less than 14 km) and with greater urbanization, with the greatest value being 0.41 W/m2. The solar radiation budget in urban areas was believed to be mainly influenced by urban structural changes in the horizontal and vertical directions. Overall, the results presented herein indicate that cumulative urbanization impacts on the natural radiation budget could evolve into an important driver of local climate change.

Global shortwave energy budget at the earth's surface from ERBE observations

NASA Technical Reports Server (NTRS)

Breon, Francois-Marie; Frouin, Robert

1994-01-01

A method is proposed to compute the net solar (shortwave) irradiance at the earth's surface from Earth Radiation Budget Experiment (ERBE) data in the S4 format. The S4 data are monthly averaged broadband planetary albedo collected at selected times during the day. Net surface shortwave irradiance is obtained from the shortwave irradiance incident at the top of the atmosphere (known) by subtracting both the shortwave energy flux reflected by the earth-atmosphere system (measured) and the energy flux absorbed by the atmosphere (modeled). Precalculated atmospheric- and surface-dependent functions that characterize scattering and absorption in the atmosphere are used, which makes the method easily applicable and computationally efficient. Four surface types are distinguished, namely, ocean, vegetation, desert, and snow/ice. Over the tropical Pacific Ocean, the estimates based on ERBE data compare well with those obtained from International Satellite Cloud Climatology Project (ISCCP) B3 data. For the 9 months analyzed the linear correlation coefficient and the standard difference between the two datasets are 0.95 and 14 W/sq m (about 6% of the average shortwave irradiance), respectively, and the bias is 15 W/sq m (higher ERBE values). The bias, a strong function of ISCCP satellite viewing zenith angle, is mostly in the ISCCP-based estimates. Over snow/ice, vegetation, and desert no comparison is made with other satellite-based estimates, but theoretical calculations using the discrete ordinate method suggest that over highly reflective surfaces (snow/ice, desert) the model, which accounts crudely for multiple reflection between the surface and clouds, may substantially overestimate the absorbed solar energy flux at the surface, especially when clouds are optically thick. The monthly surface shortwave irradiance fields produced for 1986 exhibit the main features characteristic of the earth's climate. As found in other studies, our values are generally higher than

A Global Model Simulation of Aerosol Effects of Surface Radiation Budget- Toward Understanding of the "Dimming to Brightening" Transition

NASA Technical Reports Server (NTRS)

Chin, Mian; Diehl, Thomas; Bian, Huisheng; Yu, Hongbin

2008-01-01

We present a global model study on the role aerosols play in the change of solar radiation at Earth's surface that transitioned from a decreasing (dimming) trend to an increasing (brightening) trend. Our primary objective is to understand the relationship between the long-term trends of aerosol emission, atmospheric burden, and surface solar radiation. More specifically, we use the recently compiled comprehensive global emission datasets of aerosols and precursors from fuel combustion, biomass burning, volcanic eruptions and other sources from 1980 to 2006 to simulate long-term variations of aerosol distributions and optical properties, and then calculate the multi-decadal changes of short-wave radiative fluxes at the surface and at the top of the atmosphere by coupling the GOCART model simulated aerosols with the Goddard radiative transfer model. The model results are compared with long-term observational records from ground-based networks and satellite data. We will address the following critical questions: To what extent can the observed surface solar radiation trends, known as the transition from dimming to brightening, be explained by the changes of anthropogenic and natural aerosol loading on global and regional scales? What are the relative contributions of local emission and long-range transport to the surface radiation budget and how do these contributions change with time?

A Predictor Analysis Framework for Surface Radiation Budget Reprocessing Using Design of Experiments

NASA Astrophysics Data System (ADS)

Quigley, Patricia Allison

Earth's Radiation Budget (ERB) is an accounting of all incoming energy from the sun and outgoing energy reflected and radiated to space by earth's surface and atmosphere. The National Aeronautics and Space Administration (NASA)/Global Energy and Water Cycle Experiment (GEWEX) Surface Radiation Budget (SRB) project produces and archives long-term datasets representative of this energy exchange system on a global scale. The data are comprised of the longwave and shortwave radiative components of the system and is algorithmically derived from satellite and atmospheric assimilation products, and acquired atmospheric data. It is stored as 3-hourly, daily, monthly/3-hourly, and monthly averages of 1° x 1° grid cells. Input parameters used by the algorithms are a key source of variability in the resulting output data sets. Sensitivity studies have been conducted to estimate the effects this variability has on the output data sets using linear techniques. This entails varying one input parameter at a time while keeping all others constant or by increasing all input parameters by equal random percentages, in effect changing input values for every cell for every three hour period and for every day in each month. This equates to almost 11 million independent changes without ever taking into consideration the interactions or dependencies among the input parameters. A more comprehensive method is proposed here for the evaluating the shortwave algorithm to identify both the input parameters and parameter interactions that most significantly affect the output data. This research utilized designed experiments that systematically and simultaneously varied all of the input parameters of the shortwave algorithm. A D-Optimal design of experiments (DOE) was chosen to accommodate the 14 types of atmospheric properties computed by the algorithm and to reduce the number of trials required by a full factorial study from millions to 128. A modified version of the algorithm was made

Aerosol nucleation and its role for clouds and Earth's radiative forcing in the aerosol-climate model ECHAM5-HAM

NASA Astrophysics Data System (ADS)

Kazil, J.; Stier, P.; Zhang, K.; Quaas, J.; Kinne, S.; O'Donnell, D.; Rast, S.; Esch, M.; Ferrachat, S.; Lohmann, U.; Feichter, J.

2010-05-01

Nucleation from the gas phase is an important source of aerosol particles in the Earth's atmosphere, contributing to the number of cloud condensation nuclei, which form cloud droplets. We have implemented in the aerosol-climate model ECHAM5-HAM a new scheme for neutral and charged nucleation of sulfuric acid and water based on laboratory data, and nucleation of an organic compound and sulfuric acid using a parametrization of cluster activation based on field measurements. We give details of the implementation, compare results with observations, and investigate the role of the individual aerosol nucleation mechanisms for clouds and the Earth's radiative budget. The results of our simulations are most consistent with observations when neutral and charged nucleation of sulfuric acid proceed throughout the troposphere and nucleation due to cluster activation is limited to the forested boundary layer. The globally averaged annual mean contributions of the individual nucleation processes to total absorbed solar short-wave radiation via the direct, semi-direct, indirect cloud-albedo and cloud-lifetime effects in our simulations are -1.15 W/m2 for charged H2SO4/H2O nucleation, -0.235 W/m2 for cluster activation, and -0.05 W/m2 for neutral H2SO4/H2O nucleation. The overall effect of nucleation is -2.55 W/m2, which exceeds the sum of the individual terms due to feedbacks and interactions in the model. Aerosol nucleation contributes over the oceans with -2.18 W/m2 to total absorbed solar short-wave radiation, compared to -0.37 W/m2 over land. We explain the higher effect of aerosol nucleation on Earth's radiative budget over the oceans with the larger area covered by ocean clouds, due to the larger contrast in albedo between clouds and the ocean surface compared to continents, and the larger susceptibility of pristine clouds owing to the saturation of effects. The large effect of charged nucleation in our simulations is not in contradiction with small effects seen in local

Observing Recent Changes in the Large-Scale Arctic Energy Budget

NASA Astrophysics Data System (ADS)

Porter, D. F.; Serreze, M.; Cassano, J.

2008-12-01

Changes in the large-scale energy budget of the Arctic are examined using a variety of next-generation reanalysis and observational data. An effort is made to construct a best-guess of the current arctic energy budget using a variety of atmospheric data. For the period of 2000-2005, monthly means from the Clouds and the Earth's Radiant Energy System (CERES) data represents the current most-reliable top of atmosphere radiation budget. The remaining components of the energy budget system in the arctic polar cap (defined as 70 degrees North latitude circle), comprising of the vertically-integrated storage and horizontal transports of energy, and net heat transfers between the atmosphere and the subsurface column, are diagnosed using the Japanese 25-year Reanalysis Project (JRA-25) and the NCEP/NCAR Reanalysis (NRA). The as then record-setting minimum sea-ice extent during the 2005 melt season is used as a marker of recent changes occurring in the arctic climate system. However, changes in each reanalysis differs than the satellite observations. In one example, when compared to the 2000-2005 climatology, CERES shows a shift in the peak TOA radiation from July to June in 2005, a change that is absent in the reanalyses and directly attributable to the early and pronounced albedo reduction. An earlier peak in TOA radiation can strongly modulate the flux energy convergence from lower latitudes through circulation changes. Here, the energy budget framework provides a simplified view of the pathway through which changes of key component parings occur.

A Study of Surface Temperatures, Clouds and Net Radiation

NASA Technical Reports Server (NTRS)

Dhuria, Harbans

1996-01-01

This study focused on the seasonal relationships and interactions of climate parameters such as the surface temperatures, net radiation, long wave flux, short wave flux, and clouds on a global basis. Five years of observations (December 1984 to November 1989) from the Earth Radiation Budget Experiment (ERBE) and the International Satellite Cloud Climatology Program (ISCCP) were used to study both seasonal variations and interannual variations by use of a basic radiation budget equation. In addition, the study was extended to include an analysis of the cloud forcing due El-Nino's impact on the ERBE parameters.

Radiation Measurements During Trip From Earth to Mars

NASA Image and Video Library

2013-05-30

This graphic shows the level of natural radiation detected by the Radiation Assessment Detector shielded inside NASA Mars Science Laboratory on the trip from Earth to Mars from December 2011 to July 2012.

Power-line harmonic radiation - Can it significantly affect the earth's radiation belts

NASA Technical Reports Server (NTRS)

Thorne, R. M.; Tsurutani, B. T.

1979-01-01

It has been suggested that harmonic radiation from the earth's 50- and 60-hertz power transmission lines might significantly influence the distribution of electrons in the radiation belts. On the basis of observations presented here, it seems advisable to accept such a hypothesis with caution. New evidence suggests that power-line radiation does not play any major role in the nonadiabatic dynamics of radiation belt electrons.

METEOSAT studies of clouds and radiation budget

NASA Technical Reports Server (NTRS)

Saunders, R. W.

1982-01-01

Radiation budget studies of the atmosphere/surface system from Meteosat, cloud parameter determination from space, and sea surface temperature measurements from TIROS N data are all described. This work was carried out on the interactive planetary image processing system (IPIPS), which allows interactive manipulationion of the image data in addition to the conventional computational tasks. The current hardware configuration of IPIPS is shown. The I(2)S is the principal interactive display allowing interaction via a trackball, four buttons under program control, or a touch tablet. Simple image processing operations such as contrast enhancing, pseudocoloring, histogram equalization, and multispectral combinations, can all be executed at the push of a button.

Earth's Radiation Belts: The View from Juno's Cameras

NASA Astrophysics Data System (ADS)

Becker, H. N.; Joergensen, J. L.; Hansen, C. J.; Caplinger, M. A.; Ravine, M. A.; Gladstone, R.; Versteeg, M. H.; Mauk, B.; Paranicas, C.; Haggerty, D. K.; Thorne, R. M.; Connerney, J. E.; Kang, S. S.

2013-12-01

Juno's cameras, particle instruments, and ultraviolet imaging spectrograph have been heavily shielded for operation within Jupiter's high radiation environment. However, varying quantities of >1-MeV electrons and >10-MeV protons will be energetic enough to penetrate instrument shielding and be detected as transient background signatures by the instruments. The differing shielding profiles of Juno's instruments lead to differing spectral sensitivities to penetrating electrons and protons within these regimes. This presentation will discuss radiation data collected by Juno in the Earth's magnetosphere during Juno's October 9, 2013 Earth flyby (559 km altitude at closest approach). The focus will be data from Juno's Stellar Reference Unit, Advanced Stellar Compass star cameras, and JunoCam imager acquired during coordinated proton measurements within the inner zone and during the spacecraft's inbound and outbound passages through the outer zone (L ~3-5). The background radiation signatures from these cameras will be correlated with dark count background data collected at these geometries by Juno's Ultraviolet Spectrograph (UVS) and Jupiter Energetic Particle Detector Instrument (JEDI). Further comparison will be made to Van Allen Probe data to calibrate Juno's camera results and contribute an additional view of the Earth's radiation environment during this unique event.

Inversion of the Earth spherical albedo from radiation-pressure

NASA Astrophysics Data System (ADS)

Wilkman, Olli; Herranen, Joonas; Näränen, Jyri; Virtanen, Jenni; Koivula, Hannu; Poutanen, Markku; Penttilä, Antti; Gritsevich, Maria; Muinonen, Karri

2017-04-01

We are studying the retrieval of the spherical albedo and net radiation of the Earth from the perturbations caused by the planet's radiation on the dynamics of its satellites. The spherical or Bond albedo gives the ratio of the fluxes incident on and scattered by the planet. The net radiation represents the net heat input into the planet's climate system and drives changes in its atmospheric, surface, and ocean temperatures. The ultimate aim of the study is inverting the problem and estimating the Earth albedo based on observations of satellites, simultaneously improving the space-geodetic positioning accuracy. Here we investigate the effect of the spherical albedo on satellite orbits with the help of a simplified model. We simulate the propagation of satellite orbits using a new simulation software. The simulation contains the main perturbing forces on medium and high Earth orbits, used by, e.g., navigation satellites, including the radiation pressure of reflected sunlight from the Earth. An arbitrary satellite shape model can be used, and the rotation of the satellite is modeled. In this first study, we use a box-wing satellite model with a simple surface BRDF. We also assume a diffusely reflecting Earth with a single global albedo value. We vary the Earth albedo and search for systematic effects on different orbits. Thereafter, we estimate the dependence of the albedo accuracy on the satellite positioning and timing data available. We show that the inversion of the spherical albedo with reasonable accuracy is feasible from the current space-geodetic measurements.

The Near-Earth Space Radiation for Electronics Environment

NASA Technical Reports Server (NTRS)

Stassinopoulos, E. G.; LaBel, K. A.

2004-01-01

The earth's space radiation environment is described in terms of: a) charged particles as relevant to effects on spacecraft electronics, b) the nature and distribution of trapped and transiting radiation, and c) their effect on electronic components.

Measuring Solar Radiation Incident on Earth: Solar Constant-3 (SOLCON-3)

NASA Technical Reports Server (NTRS)

Crommelynck, Dominique; Joukoff, Alexandre; Dewitte, Steven

2002-01-01

Life on Earth is possible because the climate conditions on Earth are relatively mild. One element of the climate on Earth, the temperature, is determined by the heat exchanges between the Earth and its surroundings, outer space. The heat exchanges take place in the form of electromagnetic radiation. The Earth gains energy because it absorbs solar radiation, and it loses energy because it emits thermal infrared radiation to cold space. The heat exchanges are in balance: the heat gained by the Earth through solar radiation equals the heat lost through thermal radiation. When the balance is perturbed, a temperature change and hence a climate change of the Earth will occur. One possible perturbation of the balance is the CO2 greenhouse effect: when the amount of CO2 in the atmosphere increases, this will reduce the loss of thermal infrared radiation to cold space. Earth will gain more heat and hence the temperature will rise. Another perturbation of the balance can occur through variation of the amount of energy emitted by the sun. When the sun emits more energy, this will directly cause a rise of temperature on Earth. For a long time scientists believed that the energy emitted by the sun was constant. The 'solar constant' is defined as the amount of solar energy received per unit surface at a distance of one astronomical unit (the average distance of Earth's orbit) from the sun. Accurate measurements of the variations of the solar constant have been made since 1978. From these we know that the solar constant varies approximately with the 11-year solar cycle observed in other solar phenomena, such as the occurrence of sunspots, dark spots that are sometimes visible on the solar surface. When a sunspot occurs on the sun, since the spot is dark, the radiation (light) emitted by the sun drops instantaneously. Oddly, periods of high solar activity, when a lot of sunspot numbers increase, correspond to periods when the average solar constant is high. This indicates that

The radiation balance of the earth-atmosphere system from Nimbus 3 radiation measurements

NASA Technical Reports Server (NTRS)

Raschke, E.; Vonderhaar, T. H.; Pasternak, M.; Bandeen, W. R.

1973-01-01

The radiation balance of the earth-atmosphere system and its components was computed from global measurements of radiation reflected and emitted from the earth to space. These measurements were made from the meteorological satellite Nimbus 3 during the periods from April 16 to August 15, 1969; October 3 to 17, 1969; and January 21 to February 3, 1970. Primarily the method of evaluation, its inherent assumptions, and possible error sources were discussed. Results are presented by various methods: (1) global, hemispherical, and zonal averages obtained from measurements in all semimonthly periods and (2) global maps of the absorbed solar radiation, the albedo, the outgoing longwave radiation, and the radiation balance obtained from measurements during semimonthly periods in each season (May 1 to 15, July 16 to 31, and October 3 to 17, 1969, and January 21 to February 3, 1970). Annual global averages of the albedo and of the outgoing longwave radiation were determined. These values balance to within 1 percent the annual global energy input by solar radiation that was computed for a solar constant.

Biological effects of high ultraviolet radiation on early earth--a theoretical evaluation.

PubMed

Cockell, C S

1998-08-21

The surface of early Earth was exposed to both UVC radiation (< 280 nm) and higher doses of UVB (280-315 nm) compared with the surface of present day Earth. The degree to which this radiation environment acted as a selection pressure on organisms and biological systems has rarely been theoretically examined with respect to the biologically effective irradiances that ancient organisms would receive. Here action spectra for DNA inactivation and isolated chloroplast inhibition are used to estimate biologically effective irradiances on archean Earth. Comparisons are made with present day Earth. The theoretical estimations on the UV radiation screening required to protect DNA on archean Earth compare well with field and laboratory observations on protection strategies found in present day microbial communities. They suggest that many physical and biological methods may have been effective and would have allowed for the radiation of life even under the high UV radiation regimes of archean Earth. Such strategies would also have provided effective reduction of photoinhibition by UV radiation. The data also suggest that the UV regime on the surface of Mars is not a life limiting factor per se, although other environmental factors such as desiccation and low temperatures may contribute towards the apparent lack of a surface biota.

Analysis of the Diurnal Cycle of Precipitation and its Relation to Cloud Radiative Forcing Using TRMM Products

NASA Technical Reports Server (NTRS)

Randall, David A.; Fowler, Laura D.; Lin, Xin

1998-01-01

In order to improve our understanding of the interactions between clouds, radiation, and the hydrological cycle simulated in the Colorado State University General Circulation Model (CSU GCM), we focused our research on the analysis of the diurnal cycle of precipitation, top-of-the-atmosphere and surface radiation budgets, and cloudiness using 10-year long Atmospheric Model Intercomparison Project (AMIP) simulations. Comparisons the simulated diurnal cycle were made against the diurnal cycle of Earth Radiation Budget Experiment (ERBE) radiation budget and International Satellite Cloud Climatology Project (ISCCP) cloud products. This report summarizes our major findings over the Amazon Basin.

[Anthropogenic sources of radiation hazard in the near-Earth space].

PubMed

Fedoseev, G A

2004-01-01

All plausible artificial radioactive sources entering the near-Earth space (NES) were systematized and consequences of various large radiation accidents and catastrophes to Earth and NES were analyzed. Aggressive "population" of near-Earth orbits by space stations with rotating crews, unmanned research platforms and observatories extends "borderlines" of the noosphere raising at the same time concerns about the noosphere radiation safety and global radioecology. Specifically, consideration is given to the facts of negative effects of space power reactor facilities on results of orbital astrophysical investigations.

The influence of the earth radiation on space target detection system

NASA Astrophysics Data System (ADS)

Su, Xiaofeng; Chen, FanSheng; Cuikun, .; Liuyan, .

2017-05-01

In the view of space remote sensing such as satellite detection space debris detection etc. visible band is usually used in order to have the all-weather detection capability, long wavelength infrared (LWIR) detection is also an important supplement. However, in the tow wave band, the earth can be a very strong interference source, especially in the dim target detecting. When the target is close to the earth, especially the LEO target, the background radiation of the earth will also enter into the baffle, and became the stray light through reflection, the stray light can reduce the signal to clutter ratio (SCR) of the target and make it difficult to be detected. In the visible band, the solar albedo by the earth is the main clutter source while in the LWIR band the radiation of the earth is the main clutter source. So, in this paper, we establish the energy transformation from the earth background radiation to the detection system to assess the effects of the stray light. Firstly, we discretize the surface of the earth to different unit, and using MODTRAN to calculate the radiation of the discrete point in different light and climate conditions, then, we integral all the radiation which can reach the baffle in the same observation angles to get the energy distribution, finally, according the target energy and the non-uniformity of the detector, we can calculate the design requirement of the system stray light suppression, which provides the design basis for the optical system.

Carbon and sulfur budget of the silicate Earth explained by accretion of differentiated planetary embryos

NASA Astrophysics Data System (ADS)

Li, Yuan; Dasgupta, Rajdeep; Tsuno, Kyusei; Monteleone, Brian; Shimizu, Nobumichi

2016-10-01

The abundances of volatile elements in the Earth's mantle have been attributed to the delivery of volatile-rich material after the main phase of accretion. However, no known meteorites could deliver the volatile elements, such as carbon, nitrogen, hydrogen and sulfur, at the relative abundances observed for the silicate Earth. Alternatively, Earth could have acquired its volatile inventory during accretion and differentiation, but the fate of volatile elements during core formation is known only for a limited set of conditions. Here we present constraints from laboratory experiments on the partitioning of carbon and sulfur between metallic cores and silicate mantles under conditions relevant for rocky planetary bodies. We find that carbon remains more siderophile than sulfur over a range of oxygen fugacities; however, our experiments suggest that in reduced or sulfur-rich bodies, carbon is expelled from the segregating core. Combined with previous constraints, we propose that the ratio of carbon to sulfur in the silicate Earth could have been established by differentiation of a planetary embryo that was then accreted to the proto-Earth. We suggest that the accretion of a Mercury-like (reduced) or a sulfur-rich (oxidized) differentiated body--in which carbon has been preferentially partitioned into the mantle--may explain the Earth's carbon and sulfur budgets.

Effect of atmospheric scattering and surface reflection on upwelling solar radiation

NASA Technical Reports Server (NTRS)

Suttles, J. T.; Barkstrom, B. R.; Tiwari, S. N.

1981-01-01

A study is presented of the solar radiation transfer in the complete earth-atmosphere system, and numerical results are compared with satellite data obtained during the Earth Radiation Budget Experiment on Nimbus 6, in August, 1975. Emphasis is placed on the upwelling radiance distribution at the top of the atmosphere, assumed to be at 50 km. The numerical technique is based on the finite difference method, which includes azimuth and spectral variations for the entire solar wavelength range. Detailed solar properties, atmospheric physical properties, and optical properties are used. However, since the property descriptions are based on a trade-off between accuracy and computational realities, aerosol and cloud optical properties are treated with simple approximations. The radiative transfer model is in good agreement with the satellite radiance observations. The method provides a valuable tool in analyzing satellite- and ground-based radiation budget measurements and in designing instrumentation.

Characteristic of the radiation field in low Earth orbit and in deep space.

PubMed

Reitz, Guenther

2008-01-01

The radiation exposure in space by cosmic radiation can be reduced through careful mission planning and constructive measures as example the provision of a radiation shelter, but it cannot be completely avoided. The reason for that are the extreme high energies of particles in this field and the herewith connected high penetration depth in matter. For missions outside the magnetosphere ionizing radiation is recognized as the key factor through its impact on crew health and performance. In absence of sporadic solar particle events the radiation exposure in Low Earth orbit (LEO) inside Spacecraft is determined by the galactic cosmic radiation (protons and heavier ions) and by the protons inside the South Atlantic Anomaly (SAA), an area where the radiation belt comes closer to the earth surface due to a displacement of the magnetic dipole axes from the Earth's center. In addition there is an albedo source of neutrons produced as interaction products of the primary galactic particles with the atoms of the earth atmosphere. Outside the spacecraft the dose is dominated by the electrons of the horns of the radiation belt located at about 60" latitude in Polar Regions. The radiation field has spatial and temporal variations in dependence of the Earth magnetic field and the solar cycle. The complexity of the radiation field inside a spacecraft is further increased through the interaction of the high energy components with the spacecraft shielding material and with the body of the astronauts. In interplanetary missions the radiation belt will be crossed in a couple of minutes and therefore its contribution to their radiation exposure is quite small, but subsequently the protection by the Earth magnetic field is lost, leaving only shielding measures as exposure reduction means. The report intends to describe the radiation field in space, the interaction of the particles with the magnetic field and shielding material and give some numbers on the radiation exposure in low earth

Urban Surface Radiative Energy Budgets Determined Using Aircraft Scanner Data

NASA Technical Reports Server (NTRS)

Luvall, Jeffrey C.; Quattrochi, Dale A.; Rickman, Doug L.; Estes, Maury G.; Arnold, James E. (Technical Monitor)

2002-01-01

the surface energy budget. Knowledge of it is important in any attempt to describe the radiative and mass fluxes which occur at the surface. Use of energy terms in modeling surface energy budgets allows the direct comparison of various land surfaces encountered in a urban landscape, from vegetated (forest and herbaceous) to non-vegetated (bare soil, roads, and buildings). These terms are also easily measured using remote sensing from aircraft or satellite platforms allowing one to examine the spacial variability. The partitioning of energy budget terms depends on the surface type. In natural landscapes, the partitioning is dependent on canopy biomass, leaf area index, aerodynamic roughness, and moisture status, all of which are influenced by the development stage of the ecosystem. In urban landscapes, coverage by man-made materials substantially alters the surface face energy budget. The remotely sensed data obtained from aircraft and satellites, when properly calibrated allows the measurement of important terms in the radiative surface energy budget a urban landscape scale.

Scaling of the entropy budget with surface temperature in radiative-convective equilibrium

NASA Astrophysics Data System (ADS)

Singh, Martin S.; O'Gorman, Paul A.

2016-09-01

The entropy budget of the atmosphere is examined in simulations of radiative-convective equilibrium with a cloud-system resolving model over a wide range of surface temperatures from 281 to 311 K. Irreversible phase changes and the diffusion of water vapor account for more than half of the irreversible entropy production within the atmosphere, even in the coldest simulation. As the surface temperature is increased, the atmospheric radiative cooling rate increases, driving a greater entropy sink that must be matched by greater irreversible entropy production. The entropy production resulting from irreversible moist processes increases at a similar fractional rate as the entropy sink and at a lower rate than that implied by Clausius-Clapeyron scaling. This allows the entropy production from frictional drag on hydrometeors and on the atmospheric flow to also increase with warming, in contrast to recent results for simulations with global climate models in which the work output decreases with warming. A set of approximate scaling relations is introduced for the terms in the entropy budget as the surface temperature is varied, and many of the terms are found to scale with the mean surface precipitation rate. The entropy budget provides some insight into changes in frictional dissipation in response to warming or changes in model resolution, but it is argued that frictional dissipation is not closely linked to other measures of convective vigor.

Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites

NASA Astrophysics Data System (ADS)

Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus

2017-04-01

The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.

Microclimate of a desert playa: evaluation of annual radiation, energy, and water budgets components

NASA Astrophysics Data System (ADS)

Malek, Esmaiel

2003-03-01

We set up two automatic weather stations over a playa (the flat floor of an undrained desert basin that, at times, becomes a shallow lake), approximately 65 km east-west by 130 km north-south, located in Dugway (40° 08N, 113° 27W, 1124 m above mean sea level) in northwestern Utah, USA, in 1999. These stations measured the radiation budget components, namely: incoming Rsi and outgoing Rso solar or shortwave radiation, using two Kipp and Zonen pyranometers (one inverted), the incoming Rli (or atmospheric) and outgoing Rlo (or terrestrial) longwave radiation, using two Kipp and Zonen pyrgeometers (one inverted) during the year 2000. These sensors were ventilated throughout the year to prevent dew and frost formation. Summation of these components yields the net radiation Rn. We also measured the air temperatures and humidity at 1 and 2 m and the soil moisture and temperature (Campbell Sci., Inc., CSI) to evaluate the energy budget components (latent (LE), sensible (H), and the soil (Gsur) heat fluxes). The 10 m wind speed U10 and direction (R.M. Young wind monitor), precipitation (CSI), and the surface temperature (Radiation and Energy Balance Systems, REBS) were also measured during 2000. The measurements were taken every 2 s, averaged into 20 min, continuously, throughout the year 2000. The annual comparison of radiation budget components indicates that about 34% of the annual Rsi (6937.7 MJ m-2 year-1) was reflected back to the sky as Rso, with Rli and Rlo amounting to 9943.4 MJ m-2 year-1 and 12 789.7 MJ m-2 year-1 respectively. This yields about 1634.3 MJ m-2 year-1 as Rn, which is about 24% of the annual Rsi. Of the total 1634.3 MJ m-2 year-1 available energy, about 25% was used for the process of evaporation (LE) and 77% for heating the air (H). The annual heat contribution from the soil to the energy budget amounted to 2% during the experimental period. Our studies showed that the total annual measured precipitation amounted to 108.0 mm year-1 during the

A Earth Outgoing Longwave Radiation Climate Model

NASA Astrophysics Data System (ADS)

Yang, Shi-Keng

An Earth outgoing longwave radiation (OLWR) climate model has been constructed for radiation budget study. The model consists of the upward radiative transfer parameterization of Thompson and Warren (1982), the cloud cover model of Sherr et al. (1968) and a monthly average climatology defined by the data from Crutcher and Meserve (1971) and Taljaard et al. (1969). Additional required information is provided by the empirical 100mb water vapor mixing ratio equation of Harries (1976), and the mixing ratio interpolation scheme of Briegleb and Ramanathan (1982). Cloud top temperature is adjusted so that the calculation would agree with NOAA scanning radiometer measurements. Both clear sky and cloudy sky cases are calculated and discussed for global average, zonal average and world-wide distributed cases. The results agree well with the satellite observations. The clear sky case shows that the OLWR field is highly modulated by water vapor, especially in the tropics. The strongest longitudinal variation occurs in the tropics. This variation can be mostly explained by the strong water vapor gradient. Although in the zonal average case the tropics have a minimum in OLWR, the minimum is essentially contributed by a few very low flux regions, such as the Amazon, Indonesia and the Congo. There are regions in the tropics such that their OLWR is as large as that of the subtropics. In the high latitudes, where cold air contains less water vapor, OLWR is basically modulated by the surface temperature. Thus, the topographical heat capacity becomes a dominant factor in determining the distribution. Clouds enhance water vapor modulation of OLWR. Tropical clouds have the coldest cloud top temperatures. This again increases the longitudinal variation in the region. However, in the polar region, where temperature inversion is prominent, cloud top temperature is warmer than the surface. Hence, cloud has the effect of increasing OLWR. The implication of this cloud mechanism is that the

Effect of limb darkening on earth radiation incident on a spherical satellite

NASA Technical Reports Server (NTRS)

Katzoff, S.; Smith, G. L.

1974-01-01

The thermal radiation from the earth incident on a spherical satellite depends on the angular distribution of earth-emitted radiation. An analysis is presented of this dependency, and calculated results are given, based on a published limb-darkening curve for the earth. The curve was determined from Tiros data, and is a statistical average over the entire globe between 75 deg latitude. The computed effect of limb darkening was 1.8 percent at 900 km altitude, 2.5 percent at 500 km altitude, and 3.0 percent at 300 km altitude. Below 300 km, it increased rapidly with decreasing altitude. Discussion is included of various other problems inherent in the use of orbiting spheres and stabilized flat plates to measure the heat radiated from the earth.

The Runaway Greenhouse Effect on Earth and other Planets

NASA Technical Reports Server (NTRS)

Rabbette, Maura; Pilewskie, Peter; McKay, Christopher; Young, Robert

2001-01-01

Water vapor is an efficient absorber of outgoing longwave infrared radiation on Earth and is the primary greenhouse gas. Since evaporation increases with increasing sea surface temperature, and the increase in water vapor further increases greenhouse warming, there is a positive feedback. The runaway greenhouse effect occurs if this feedback continues unchecked until all the water has left the surface and enters the atmosphere. For Mars and the Earth the runaway greenhouse was halted when water vapor became saturated with respect to ice or liquid water respectively. However, Venus is considered to be an example of a planet where the runaway greenhouse effect did occur, and it has been speculated that if the solar luminosity were to increase above a certain limit, it would also occur on the Earth. Satellite data acquired during the Earth Radiation Budget Experiment (ERBE) under clear sky conditions shows that as the sea surface temperature (SST) increases, the rate of outgoing infrared radiation at the top of the atmosphere also increases, as expected. Over the pacific warm pool where the SST exceeds 300 K the outgoing radiation emitted to space actually decreases with increasing SST, leading to a potentially unstable system. This behavior is a signature of the runaway greenhouse effect on Earth. However, the SST never exceeds 303K, thus the system has a natural cap which stops the runaway. According to Stefan-Boltzmann's law the amount of heat energy radiated by the Earth's surface is proportional to (T(sup 4)). However, if the planet has a substantial atmosphere, it can absorb all infrared radiation from the lower surface before the radiation penetrates into outer space. Thus, an instrument in space looking at the planet does not detect radiation from the surface. The radiation it sees comes from some level higher up. For the earth#s atmosphere the effective temperature (T(sub e)) has a value of 255 K corresponding to the middle troposphere, above most of the

The Potential for Collocated AGLP and ERBE data for Fire, Smoke, and Radiation Budget Studies

NASA Technical Reports Server (NTRS)

Christropher, S. A.; Chou, J.

1997-01-01

One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burn- ing. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of fires for September 1985, and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed.

The Potential for Collocated AGLP and ERBE Data for Fire, Smoke, and Radiation Budget Studies

NASA Technical Reports Server (NTRS)

Christopher, S. A.; Chou, J.

1997-01-01

One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burning. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of tires for September 1985, and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed.

The Potential for Collocated AGLP and ERBE Data for Fire, Smoke, and Radiation Budget Studies

NASA Technical Reports Server (NTRS)

Christopher, S. A.; Chou, J.

1997-01-01

One month of the Advanced Very High Resolution Radiometer (AVHRR) Global Area Coverage (GAC) Land Pathfinder (AGLP) data from September 1985 are used to examine the spatial and temporal distribution of fires over four major ecosystems in South America. The Earth Radiation Budget Experiment (ERBE) scanner data are used to examine the top of atmosphere (TOA) shortwave and longwave fluxes over smoke generated from biomass burning. The relationship between the AGLP-derived Normalized Difference Vegetation Index (NDVI) and the ERBE-estimated clear sky albedos are also examined as a function of the four ecosystems. This study shows that the grassland areas in South America have the highest number of fires for September 1985. and their corresponding NDVI values are smaller than the tropical rainforest region where the number of fires were comparatively small. Clear sky statistics accumulated during the days when smoke was not present show that clear sky albedos derived from ERBE are higher for grassland areas when compared to the tropical rainforest. The results show that the AGLP can be used to determine the spatial and temporal distribution of fires along with vegetation characteristics, while ERBE data can provide necessary information on broadband albedos and regional top of atmosphere radiative impacts of biomass burning aerosols. Since the AGLP data are available from 1981 to the present day, several climate-related issues can be addressed,

Satellite Estimates of the Direct Radiative Forcing of Biomass Burning Aerosols Over South America and Africa

NASA Technical Reports Server (NTRS)

Christopher, Sundar A.; Wang, Min; Kliche, Donna V.; Berendes, Todd; Welch, Ronald M.; Yang, S.K.

1997-01-01

Atmospheric aerosol particles, both natural and anthropogenic are important to the earth's radiative balance. Therefore it is important to provide adequate validation information on the spatial, temporal and radiative properties of aerosols. This will enable us to predict realistic global estimates of aerosol radiative effects more confidently. The current study utilizes 66 AVHRR LAC (Local Area Coverage) and coincident Earth Radiation Budget Experiment (ERBE) images to characterize the fires, smoke and radiative forcings of biomass burning aerosols over four major ecosystems of South America.

Evaluation of 20-min and Annual Radiation Budget Components and Cloudiness in a Mountainous Valley

NASA Astrophysics Data System (ADS)

Malek, E.

2007-05-01

Logan, Utah (USA) is among cities located in the mountainous valley in the western portion of Rocky Mountains in North America. It is the county seat of Cache Valley, a metropolitan area with a population of about 100,000. The valley had the polluted air in the USA during January 2004. To evaluate the daily and annual radiation budget and cloudiness in this mountainous valley, we set up a radiation station in the middle of the valley to measure the 20- min radiation budget components namely: incoming (Rso) and outgoing (Rso) solar or shortwave radiation, using to CM21 Kipp and Zonen (one inverted) and incoming (Rli) (or atmospheric) and outgoing (Rlo) or terrestrial) longwave radiation using two CG1 Kipp and Zonen Pyrgeometers (one inverted) during the year of 2003. All pyranometers and Pyrgeometers were ventilated with four CV2 Kipp and Zonen ventilation systems throughout the year to prevent deposition of dew, frost and snow, which otherwise would disturb the measurements. We also measured the 2-m air temperature and relative humidity along with surface temperature. All measurements were taken every 2 s, averaged to 20 min, continuously throughout the year 2000. A Met One heated rain gauge measured precipitation. Comparison of the annual radiation budget components indicates that about 25% of the annual Rsi (5848.6 MJ/ (squared m-y)) was reflected back to sky as Rso. Rli and Rlo amounted to 9968.7 and 13303.5 MJ/ (squared m-y)), respectively. This yielded about 1364.9 MJ/ (squared m- y)) available energy (Rn). Having the 2-m air temperature and moisture data and comparison between the theoretical and the measured longwave radiation, we evaluated the 20-m cloudy conditions throughout the year of 2003. The average cloud base height was 587 m (ranged from zero for foggy conditions to about 3000 m). Annual cloudiness contributed about 139.1 MJ/ (squared m-y)) more energy in this valley.

Problems of sampling and radiation balances: Their problematics

NASA Technical Reports Server (NTRS)

Crommelynck, D.

1980-01-01

Problems associated with the measurement of the Earth radiation balances are addressed. It is demonstrated that the knowledge of the different radiation budgets with their components is largely dependent on the space time sampling of the radiation field of the Earth atmosphere system. Whichever instrumental approach is adopted (wide angle view of high resolution) it affects the space time integration of the fluxes measured directly or calculated. In this case the necessary knowledge of the reflection pattern depends in addition on the angular sampling of the radiances. A series of questions is considered, the answers of which are a prerequisite to the the organization of a global observation system.

The Regional Influence of the Arctic Oscillation and Arctic Dipole on the Wintertime Arctic Surface Radiation Budget and Sea Ice Growth

NASA Technical Reports Server (NTRS)

Hegyi, Bradley M.; Taylor, Patrick C.

2017-01-01

An analysis of 2000-2015 monthly Clouds and the Earth's Radiant Energy System-Energy Balanced and Filled (CERES-EBAF) and Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA2) data reveals statistically significant fall and wintertime relationships between Arctic surface longwave (LW) radiative flux anomalies and the Arctic Oscillation (AO) and Arctic Dipole (AD). Signifying a substantial regional imprint, a negative AD index corresponds with positive downwelling clear-sky LW flux anomalies (greater than10W m(exp -2)) north of western Eurasia (0 deg E-120 deg E) and reduced sea ice growth in the Barents and Kara Seas in November-February. Conversely, a positive AO index coincides with negative clear-sky LW flux anomalies and minimal sea ice growth change in October-November across the Arctic. Increased (decreased) atmospheric temperature and water vapor coincide with the largest positive (negative) clear-sky flux anomalies. Positive surface LW cloud radiative effect anomalies also accompany the negative AD index in December-February. The results highlight a potential pathway by which Arctic atmospheric variability influences the regional surface radiation budget over areas of Arctic sea ice growth.

The NASA/GEWEX Surface Radiation Budget: Integrated Data Product With Reprocessed Radiance, Cloud, and Meteorology Inputs

NASA Astrophysics Data System (ADS)

Stackhouse, P. W.; Gupta, S. K.; Cox, S. J.; Mikovitz, J. C.; Zhang, T.

2015-12-01

The NASA/GEWEX Surface Radiation Budget (SRB) project produces shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. Spatial resolution is 1 degree. The current release 3.0 (available at gewex-srb.larc.nasa.gov) uses the International Satellite Cloud Climatology Project (ISCCP) DX product for pixel level radiance and cloud information. This product is subsampled to 30 km. ISCCP is currently recalibrating and recomputing their entire data series, to be released as the H product, at 10km resolution. The ninefold increase in pixel number will allow SRB a higher resolution gridded product (e.g. 0.5 degree), as well as the production of pixel-level fluxes. Other key input improvements include a detailed aerosol history using the Max Planck Institut Aerosol Climatology (MAC), temperature and moisture profiles from HIRS, and new topography, surface type, and snow/ice. At the time of abstract submission, results from the year 2007 have been produced. More years will be added as ISCCP reprocessing occurs. Here we present results for the improved GEWEX Shortwave and Longwave algorithm (GSW and GLW) with new ISCCP data, the various other improved input data sets and the incorporation of many additional internal SRB model improvements. Improvements in GSW include an expansion of the number of wavelength bands from five to eighteen, and the inclusion of ice cloud vs. water cloud radiative transfer. The SRB data produced will be released as part of the Release 4.0 Integrated Product, recognizing the interdependence of the radiative fluxes with other GEWEX products providing estimates of the Earth's global water and energy cycle (I.e., ISCCP, SeaFlux, LandFlux, NVAP, etc.).

Infrared Imaging and Characterization of Exoplanets: Can we Detect Earth-Twins on a Budget?

NASA Technical Reports Server (NTRS)

Danchi, William

2010-01-01

During the past decade considerable progress has been made developing techniques that can be used to detect and characterize Earth twins in the mid- infrared (7-20 microns). The principal technique is called nulling interferometry, and it was invented by Bracewell in the late 1970's. The nulling technique is an interferometric equivalent of an optical coronagraph. At the present time most of the technological hurdles have been overcome for a space mission to be able to begin Phase A early in the next decade, and it is possible to detect and characterize Earth-twins on a mid- sized strategic mission budget ($600-800 million). I will review progress on this exciting method of planet detection in the context of recent work on the Exoplanet Community Forum and the US Decadal Survey (Astro2010), including biomarkers, technological progress, mission concepts, the theory of these instruments, and a.comparison of the discovery space of this technique with others also under consideration.

The radiation budget of stratocumulus clouds measured by tethered balloon instrumentation: Variability of flux measurements

NASA Technical Reports Server (NTRS)

Duda, David P.; Stephens, Graeme L.; Cox, Stephen K.

1990-01-01

Measurements of longwave and shortwave radiation were made using an instrument package on the NASA tethered balloon during the FIRE Marine Stratocumulus experiment. Radiation data from two pairs of pyranometers were used to obtain vertical profiles of the near-infrared and total solar fluxes through the boundary layer, while a pair of pyrgeometers supplied measurements of the longwave fluxes in the cloud layer. The radiation observations were analyzed to determine heating rates and to measure the radiative energy budget inside the stratocumulus clouds during several tethered balloon flights. The radiation fields in the cloud layer were also simulated by a two-stream radiative transfer model, which used cloud optical properties derived from microphysical measurements and Mie scattering theory.

Enhanced orbit determination filter sensitivity analysis: Error budget development

NASA Technical Reports Server (NTRS)

Estefan, J. A.; Burkhart, P. D.

1994-01-01

An error budget analysis is presented which quantifies the effects of different error sources in the orbit determination process when the enhanced orbit determination filter, recently developed, is used to reduce radio metric data. The enhanced filter strategy differs from more traditional filtering methods in that nearly all of the principal ground system calibration errors affecting the data are represented as filter parameters. Error budget computations were performed for a Mars Observer interplanetary cruise scenario for cases in which only X-band (8.4-GHz) Doppler data were used to determine the spacecraft's orbit, X-band ranging data were used exclusively, and a combined set in which the ranging data were used in addition to the Doppler data. In all three cases, the filter model was assumed to be a correct representation of the physical world. Random nongravitational accelerations were found to be the largest source of error contributing to the individual error budgets. Other significant contributors, depending on the data strategy used, were solar-radiation pressure coefficient uncertainty, random earth-orientation calibration errors, and Deep Space Network (DSN) station location uncertainty.

West Antarctic Ice Sheet cloud cover and surface radiation budget from NASA A-Train satellites

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

Scott, Ryan C.; Lubin, Dan; Vogelmann, Andrew M.

Clouds are an essential parameter of the surface energy budget influencing the West Antarctic Ice Sheet (WAIS) response to atmospheric warming and net contribution to global sea-level rise. A four-year record of NASA A-Train cloud observations is combined with surface radiation measurements to quantify the WAIS radiation budget and constrain the three-dimensional occurrence frequency, thermodynamic phase partitioning, and surface radiative effect of clouds over West Antarctica (WA). The skill of satellite-modeled radiative fluxes is confirmed through evaluation against measurements at four Antarctic sites (WAIS Divide Ice Camp, Neumayer, Syowa, and Concordia Stations). And due to perennial high-albedo snow and icemore » cover, cloud infrared emission dominates over cloud solar reflection/absorption leading to a positive net all-wave cloud radiative effect (CRE) at the surface, with all monthly means and 99.15% of instantaneous CRE values exceeding zero. The annual-mean CRE at theWAIS surface is 34 W m -2, representing a significant cloud-induced warming of the ice sheet. Low-level liquid-containing clouds, including thin liquid water clouds implicated in radiative contributions to surface melting, are widespread and most frequent in WA during the austral summer. Clouds warm the WAIS by 26 W m -2, in summer, on average, despite maximum offsetting shortwave CRE. Glaciated cloud systems are strongly linked to orographic forcing, with maximum incidence on the WAIS continuing downstream along the Transantarctic Mountains.« less

West Antarctic Ice Sheet cloud cover and surface radiation budget from NASA A-Train satellites

DOE PAGES

Scott, Ryan C.; Lubin, Dan; Vogelmann, Andrew M.; ...

2017-04-26

Clouds are an essential parameter of the surface energy budget influencing the West Antarctic Ice Sheet (WAIS) response to atmospheric warming and net contribution to global sea-level rise. A four-year record of NASA A-Train cloud observations is combined with surface radiation measurements to quantify the WAIS radiation budget and constrain the three-dimensional occurrence frequency, thermodynamic phase partitioning, and surface radiative effect of clouds over West Antarctica (WA). The skill of satellite-modeled radiative fluxes is confirmed through evaluation against measurements at four Antarctic sites (WAIS Divide Ice Camp, Neumayer, Syowa, and Concordia Stations). And due to perennial high-albedo snow and icemore » cover, cloud infrared emission dominates over cloud solar reflection/absorption leading to a positive net all-wave cloud radiative effect (CRE) at the surface, with all monthly means and 99.15% of instantaneous CRE values exceeding zero. The annual-mean CRE at theWAIS surface is 34 W m -2, representing a significant cloud-induced warming of the ice sheet. Low-level liquid-containing clouds, including thin liquid water clouds implicated in radiative contributions to surface melting, are widespread and most frequent in WA during the austral summer. Clouds warm the WAIS by 26 W m -2, in summer, on average, despite maximum offsetting shortwave CRE. Glaciated cloud systems are strongly linked to orographic forcing, with maximum incidence on the WAIS continuing downstream along the Transantarctic Mountains.« less

Effects of radiation and turbulence on the diabatic heating and water budget of the stratiform region of a tropical cloud cluster

NASA Technical Reports Server (NTRS)

Churchill, Dean D.; Houze, Robert A., Jr.

1991-01-01

A twi-dimensional kinematic model has been used to diagnose the thermodynamic, water vapor, and hydrometeor fields of the stratiform clouds associated with a mesoscale tropical cloud cluster. The model incorporates ice- and water-cloud microphysics, visible and infrared radiation, and convective adjustment. It is intended to determine the relative contributions of radiation, mycrophysics, and turbulence to diabatic heating, and the effects that radiation has on the water budget of the cluster in the absence of dynamical interactions. The model has been initialized with thermodynamic fields and wind velocities diagnosed from a GATE tropical squall line. It is found that radiation does not directly affect the water budget of the stratiform region, and any radiative effect on hydrometeors must involve interaction with dynamics.

Clouds and the Earth's Radiant Energy System (CERES) Visualization Single Satellite Footprint (SSF) Plot Generator

NASA Technical Reports Server (NTRS)

Barsi, Julia A.

1995-01-01

The first Clouds and the Earth's Radiant Energy System (CERES) instrument will be launched in 1997 to collect data on the Earth's radiation budget. The data retrieved from the satellite will be processed through twelve subsystems. The Single Satellite Footprint (SSF) plot generator software was written to assist scientists in the early stages of CERES data analysis, producing two-dimensional plots of the footprint radiation and cloud data generated by one of the subsystems. Until the satellite is launched, however, software developers need verification tools to check their code. This plot generator will aid programmers by geolocating algorithm result on a global map.

Empirical Quantification of the Runaway Greenhouse Limit on Earth

NASA Astrophysics Data System (ADS)

Goldblatt, C.; Dewey, M. C.

2015-12-01

There have been many modeling studies of the runaway greenhouse effect and the conditions required to produce one on an Earth-like planet, however these models have not been verified with empirical evidence. It has been suggested that the Earth's tropics may be near a state of localized runaway greenhouse, meaning the surface temperature and atmospheric composition in those areas could cause runaway greenhouse, were it not for the tempering effects of meridional heat transport and circulation (Pierrehumbert, 1995). Using the assumption that some areas of the Earth's tropics may be under these conditions, this study uses measurements of the atmospheric properties, surface properties, and radiation budgets of these areas to quantify a radiation limit for runaway greenhouse on Earth, by analyzing the dependence of outgoing longwave radiation (OLR) at the top of the atmosphere on surface temperature and total column water vapour. An upper limit on OLR for clear-sky conditions was found between 289.8 W/m2 and 292.2 W/m2, which occurred at surface temperatures near 300K. For surface temperatures above this threshold, total column water vapour increased, but OLR initially decreased and then remained relatively constant, between 273.6 W/m2 and 279.7 W/m2. These limits are in good agreement with recent modeling results (Goldblatt et al., 2013), supporting the idea that some of the Earth's tropics may be in localized runaway greenhouse, and that radiation limits for runaway greenhouse on Earth can be empirically derived. This research was done as part of Maura Dewey's undergraduate honours thesis at the University of Victoria. Refs: Robert T. Pierrehumbert. Thermostats, radiator fins, and the local runaway greenhouse. Journal of Atmospheric Sciences, 52(10):1784-1806, 1995. Colin Goldblatt, Tyler D. Robinson, Kevin J. Zahnle, and David Crisp. Low simulated radiation limit for runaway greenhouse climates. Nature Geoscience, 6:661-667, 2013.

Internal Charging Design Environments for the Earths Radiation Belts

NASA Technical Reports Server (NTRS)

Minow, Joseph I.; Edwards, David L.

2009-01-01

Relativistic electrons in the Earth's radiation belts are a widely recognized threat to spacecraft because they penetrate lightly shielded vehicle hulls and deep into insulating materials where they accumulate to sufficient levels to produce electrostatic discharges. Strategies for evaluating the magnitude of the relativistic electron flux environment and its potential for producing ESD events are varied. Simple "rule of thumb" estimates such as the widely used 10(exp 10) e-/sq cm fluence within 10 hour threshold for the onset of pulsing in dielectric materials provide a quick estimate of when to expect charging issues. More sophisticated strategies based on models of the trapped electron flux within the Earth s magnetic field provide time dependent estimates of electron flux along spacecraft orbits and orbit integrate electron flux. Finally, measurements of electron flux can be used to demonstrate mean and extreme relativistic electron environments. This presentation will evaluate strategies used to specify energetic electron flux and fluence environments along spacecraft trajectories in the Earth s radiation belts.

Measurement of solar radiation at the Earth's surface

NASA Technical Reports Server (NTRS)

Bartman, F. L.

1982-01-01

The characteristics of solar energy arriving at the surface of the Earth are defined and the history of solar measurements in the United States presented. Radiation and meteorological measurements being made at solar energy meteorological research and training sites and calibration procedures used there are outlined. Data illustrating the annual variation in daily solar radiation at Ann Arbor, Michigan and the diurnal variation in radiation at Albuquerque, New Mexico are presented. Direct normal solar radiation received at Albuquerque is contrasted with that received at Maynard, Massachusetts. Average measured global radiation for a period of one year for four locations under clear skies, 50% cloud cover, and 100% cloud cover is given and compared with the solar radiation at the top of the atmosphere. The May distribution of mean daily direct solar radiation and mean daily global solar radiation over the United States is presented. The effects of turbidity on the direct and circumsolar radiation are shown.

Impacts of Climate Change and Land use Changes on Land Surface Radiation and Energy Budgets

USDA-ARS?s Scientific Manuscript database

Land surface radiation and energy budgets are critical to address a variety of scientific and application issues related to climate trends, weather predictions, hydrologic and biogeophysical modeling, and the monitoring of ecosystem health and agricultural crops. This is an introductory paper to t...

Terrestrial outgoing radiation measurements with small satellite mission

NASA Astrophysics Data System (ADS)

Zhu, Ping; Dewitte, Steven; Karatekin, Ozgur; Chevalier, André; Conscience, Christian

2015-04-01

The solar force is the main driver of the Earth's climate. For a balanced climate system, the incoming solar radiation is equal to the sum of the reflected visible and reemitted thermal radiation at top of the atmosphere (TOA). Thus the energy imbalance plays an important role to diagnose the health of nowadays climate. However it remains a challenge to directly track the small Energy imbalance in Earth's Radiation Budget (EIERB) from space due to the complicities of the Earth's climate system and the limitation on long term stability of space instrument. The terrestrial outgoing radiation (TOR) has been recoded with a Bolometric Oscillation Sensor onboard PICAD microsatellite. In this presentation, we will report the three years TOR observed with PICARD-BOS and its further comparison with the CERES product. However the data acquired from this mission is still not enough to derive the EIERB. But the heritage gained from this experiment shields a light on the EIERB tracking with the small satellite even a cubesat mission.

Characterizing energy budget variability at a Sahelian site: a test of NWP model behaviour

NASA Astrophysics Data System (ADS)

Mackie, Anna; Palmer, Paul I.; Brindley, Helen

2017-12-01

We use observations of surface and top-of-the-atmosphere (TOA) broadband radiation fluxes determined from the Atmospheric Radiation Measurement programme mobile facility, the Geostationary Earth Radiation Budget (GERB) and Spinning Enhanced Visible and Infrared Imager (SEVIRI) instruments and a range of meteorological variables at a site in the Sahel to test the ability of the ECMWF Integrated Forecasting System cycle 43r1 to describe energy budget variability. The model has daily average biases of -12 and 18 W m-2 for outgoing longwave and reflected shortwave TOA radiation fluxes, respectively. At the surface, the daily average bias is 12(13) W m-2 for the longwave downwelling (upwelling) radiation flux and -21(-13) W m-2 for the shortwave downwelling (upwelling) radiation flux. Using multivariate linear models of observation-model differences, we attribute radiation flux discrepancies to physical processes, and link surface and TOA fluxes. We find that model biases in surface radiation fluxes are mainly due to a low bias in ice water path (IWP), poor description of surface albedo and model-observation differences in surface temperature. We also attribute observed discrepancies in the radiation fluxes, particularly during the dry season, to the misrepresentation of aerosol fields in the model from use of a climatology instead of a dynamic approach. At the TOA, the low IWP impacts the amount of reflected shortwave radiation while biases in outgoing longwave radiation are additionally coupled to discrepancies in the surface upwelling longwave flux and atmospheric humidity.

Impact of biomass burning plume on radiation budget and atmospheric dynamics over the arctic

NASA Astrophysics Data System (ADS)

Lisok, Justyna; Pedersen, Jesper; Ritter, Christoph; Markowicz, Krzysztof M.; Malinowski, Szymon; Mazzola, Mauro; Udisti, Roberto; Stachlewska, Iwona S.

2018-04-01

The aim of the research was to determine the impact of July 2015 biomass burning event on radiative budget, atmospheric stratification and turbulence over the Arctic using information about the vertical structure of the aerosol load from the ground-based data. MODTRAN simulations indicated very high surface radiative cooling (forcing of -150 Wm-2) and a heating rate of up to 1.8 Kday-1 at 3 km. Regarding LES results, a turbulent layer at around 3 km was clearly seen after 48 h of simulation.

Insights on How NASA's Earth Observing System (EOS) Monitors Our World Environment

NASA Technical Reports Server (NTRS)

King, Michael D.

2000-01-01

The Earth Observing System (EOS) is a space-based observing system comprised of a series of satellite sensors by which scientists can monitor the Earth, a Data and Information System (EOSDIS) enabling researchers worldwide to access the satellite data, and an interdisciplinary science research program to interpret the satellite data. During this year, four EOS science missions were launched, representing observations of (1) total solar irradiance, (2) Earth radiation budget, (3) land cover and land use change, (4) ocean processes (vector wind, sea surface temperature, and ocean color), (5) atmospheric processes (aerosol and cloud properties, water vapor, and temperature and moisture profiles), and (6) tropospheric chemistry. In succeeding years many more satellites will be launched that will contribute immeasurably to our understanding of the Earth's environment. In this presentation I will describe how scientists are using EOS data to examine land use and natural hazards, environmental air quality, including dust storms over the world's deserts, cloud and radiation properties, sea surface temperature, and winds over the ocean.

Discover Earth: Earth's Energy Budget or Can You Spare a Sun?

NASA Technical Reports Server (NTRS)

Gates, Tom; Peters, Dale E.; Steeley, Jeanne

1999-01-01

Discover Earth is a NASA-sponsored project for teachers of grades 5-12, designed to: enhance understanding of the Earth as an integrated system enhance the interdisciplinary approach to science instruction, and provide classroom materials that focus on those goals. Discover Earth is conducted by the Institute for Global Environmental Strategies in collaboration with Dr. Eric Barron, Director, Earth System Science Center, The Pennsylvania State University; and Dr. Robert Hudson, Chair, the Department of Meteorology, University of Maryland at College Park.

Impact of fire on global land carbon, water, and energy budgets and climate during the 20th century through changing ecosystems

NASA Astrophysics Data System (ADS)

Li, F.; Lawrence, D. M.; Bond-Lamberty, B. P.; Levis, S.

2016-12-01

Fire is an integral Earth system process and the primary form of terrestrial ecosystem disturbance on a global scale. Here we provide the first quantitative assessment and understanding on fire's impact on global land carbon, water, and energy budgets and climate through changing ecosystems. This is done by quantifying the difference between 20th century fire-on and fire-off simulations using the Community Earth System Model (CESM1.2). Results show that fire decreases the net carbon gain of global terrestrial ecosystems by 1.0 Pg C/yr averaged across the 20th century, as a result of biomass and peat burning (1.9 Pg C/yr) partly offset by changing gross primary productivity, respiration, and land-use carbon loss (-0.9 Pg C/yr). In addition, fire's effect on global carbon budget intensifies with time. Fire significantly reduces land evapotranspiration (ET) by 600 km3/yr and increases runoff, but has limited impact on precipitation. The impact on ET and runoff is most clearly seen in the tropical savannas, African rainforest, and some boreal and Southern Asian forests mainly due to fire-induced reduction in the vegetation canopy. It also weakens both the significant upward trend in global land ET prior to the 1950s and the downward trend from 1950 to 1985 by 35%. Fire-induced changes in land ecosystems affects global energy budgets by significantly reducing latent heating and surface net radiation. Fire changes surface radiative budget dominantly by raising surface upward longwave radiation and net longwave radiation. It also increases the global land average surface air temperature (Tas) by 0.04°C, and significantly increases wind speed and decreases surface relative humidity. The fire-induced change in wind speed, Tas, and relative humidity implies a positive feedback loop between fire and climate. Moreover, fire-induced changes in land ecosystems contribute 20% of strong global land warming during 1910-1940, which provides a new mechanism for the early 20th

The Nimbus satellites - Pioneering earth observers

NASA Technical Reports Server (NTRS)

White, Carolynne

1990-01-01

The many scientific achievements of the Nimbus series of seven satellites for low-altitude atmospheric research and global weather surveillance are reviewed. The series provides information on fishery resources, weather modeling, atmospheric pollution monitoring, earth's radiation budget, ozone monitoring, ocean dynamics, and the effects of cloudiness. Data produced by the forty-eight instruments and sensors flown on the satellites are applied in the fields of oceanography, hydrology, geology, geomorphology, geography, cartography, agriculture and meteorology. The instruments include the Coastal Zone Color Scanner (which depicts phytoplankton concentrations in coastal areas), the Scanning Multichannel Microwave Radiometer (which measures sea-surface temperatures and sea-surface wind-speed), and the Total Ozone Mapping Spectrometer (which provides information on total amounts of ozone in the earth's atmosphere).

Space radiation dosimetry in low-Earth orbit and beyond.

PubMed

Benton, E R; Benton, E V

2001-09-01

Space radiation dosimetry presents one of the greatest challenges in the discipline of radiation protection. This is a result of both the highly complex nature of the radiation fields encountered in low-Earth orbit (LEO) and interplanetary space and of the constraints imposed by spaceflight on instrument design. This paper reviews the sources and composition of the space radiation environment in LEO as well as beyond the Earth's magnetosphere. A review of much of the dosimetric data that have been gathered over the last four decades of human space flight is presented. The different factors affecting the radiation exposures of astronauts and cosmonauts aboard the International Space Station (ISS) are emphasized. Measurements made aboard the Mir Orbital Station have highlighted the importance of both secondary particle production within the structure of spacecraft and the effect of shielding on both crew dose and dose equivalent. Roughly half the dose on ISS is expected to come from trapped protons and half from galactic cosmic rays (GCRs). The dearth of neutron measurements aboard LEO spacecraft and the difficulty inherent in making such measurements have led to large uncertainties in estimates of the neutron contribution to total dose equivalent. Except for a limited number of measurements made aboard the Apollo lunar missions, no crew dosimetry has been conducted beyond the Earth's magnetosphere. At the present time we are forced to rely on model-based estimates of crew dose and dose equivalent when planning for interplanetary missions, such as a mission to Mars. While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars. c2001 Elsevier Science B.V. All rights reserved.

NASA/GEWEX Surface Radiation Budget: First Results From The Release 4 GEWEX Integrated Data Products

NASA Astrophysics Data System (ADS)

Stackhouse, Paul; Cox, Stephen; Gupta, Shashi; Mikovitz, J. Colleen; zhang, taiping

2016-04-01

The NASA/GEWEX Surface Radiation Budget (SRB) project produces shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. Spatial resolution is 1 degree. The current release 3 (available at gewex-srb.larc.nasa.gov) uses the International Satellite Cloud Climatology Project (ISCCP) DX product for pixel level radiance and cloud information. This product is subsampled to 30 km. ISCCP is currently recalibrating and recomputing their entire data series, to be released as the H product, at 10km resolution. The ninefold increase in pixel number should help improve the RMS of the existing products and allow for future higher resolution SRB gridded product (e.g. 0.5 degree). In addition to the input data improvements, several important algorithm improvements have been made. Most notable has been the adaptation of Angular Distribution Models (ADMs) from CERES to improve the initial calculation of shortwave TOA fluxes, from which the surface flux calculations follow. Other key input improvements include a detailed aerosol history using the Max Planck Institut Aerosol Climatology (MAC), temperature and moisture profiles from HIRS, and new topography, surface type, and snow/ice. Here we present results for the improved GEWEX Shortwave and Longwave algorithm (GSW and GLW) with new ISCCP data, the various other improved input data sets and the incorporation of many additional internal SRB model improvements. As of the time of abstract submission, results from 2007 have been produced with ISCCP H availability the limiting factor. More SRB data will be produced as ISCCP reprocessing continues. The SRB data produced will be released as part of the Release 4.0 Integrated Product, recognizing the interdependence of the radiative fluxes with other GEWEX products providing estimates of the Earth's global water and energy cycle (I.e., ISCCP, SeaFlux, LandFlux, NVAP, etc.).

Human response to high-background radiation environments on Earth and in space

NASA Astrophysics Data System (ADS)

Durante, M.; Manti, L.

The main long-term goal of the space exploration program is the colonization of the planets of the Solar System The high cosmic radiation equivalent dose rate represents a major problem for a stable and safe colonization of the planets The dose rate on Mars ranges between 60 and 150 mSv year depending on the Solar cycle and altitude and can reach values as high as 360 mSv year on the Moon The average dose rate on the Earth is about 3 mSv year reduced to about 1 mSv year excluding the internal exposure to Rn daughters However some areas of the Earth have anomalously high levels of background radiation Values 200-400 times higher than the world average are found in regions where monazite sand deposits are abundant Population in Tibet experience a high cosmic radiation background Epidemiological studies did not detect any adverse health effects in the populations living in those high-background radiation areas on Earth Chromosomal aberrations in the peripheral blood lymphocytes from the population living in the high-background radiation areas have been measured in several studies because the chromosomal damage represents an early biomarker of cancer risk Similar cytogenetic studies have been recently performed in cohort of astronauts involved in single or repeated space flights over many years A comparison of the cytogenetic findings in populations exposed at high dose rate on Earth or in space will be described

Radiation Transfer in the Atmosphere: Scattering

NASA Technical Reports Server (NTRS)

Mishchenko, M.; Travis, L.; Lacis, Andrew A.

2014-01-01

Sunlight illuminating the Earth's atmosphere is scattered by gas molecules and suspended particles, giving rise to blue skies, white clouds, and optical displays such as rainbows and halos. By scattering and absorbing the shortwave solar radiation and the longwave radiation emitted by the underlying surface, cloud and aerosol particles strongly affect the radiation budget of the terrestrial climate system. As a consequence of the dependence of scattering characteristics on particle size, morphology, and composition, scattered light can be remarkably rich in information on particle properties and thus provides a sensitive tool for remote retrievals of macro- and microphysical parameters of clouds and aerosols.

Storm- Time Dynamics of Ring Current Protons: Implications for the Long-Term Energy Budget in the Inner Magnetosphere.

NASA Astrophysics Data System (ADS)

Gkioulidou, M.; Ukhorskiy, A. Y.; Mitchell, D. G.; Lanzerotti, L. J.

2015-12-01

The ring current energy budget plays a key role in the global electrodynamics of Earth's space environment. Pressure gradients developed in the inner magnetosphere can shield the near-Earth region from solar wind-induced electric fields. The distortion of Earth's magnetic field due to the ring current affects the dynamics of particles contributing both to the ring current and radiation belts. Therefore, understanding the long-term evolution of the inner magnetosphere energy content is essential. We have investigated the evolution of ring current proton pressure (7 - 600 keV) in the inner magnetosphere based on data from the Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) instrument aboard Van Allen Probe B throughout the year 2013. We find that although the low-energy component of the protons (< 80 keV) is governed by convective timescales and is very well correlated with the Dst index, the high-energy component (>100 keV) varies on much longer timescales and shows either no or anti-correlation with the Dst index. Interestingly, the contributions of the high- and low-energy protons to the total energy content are comparable. Our results indicate that the proton dynamics, and as a consequence the total energy budget in the inner magnetosphere (inside geosynchronous orbit), is not strictly controlled by storm-time timescales as those are defined by the Dst index.

The oceanic origin of path-independent carbon budgets.

PubMed

MacDougall, Andrew H

2017-09-04

Virtually all Earth system models (ESM) show a near proportional relationship between cumulative emissions of CO 2 and change in global mean temperature, a relationship which is independent of the emissions pathway taken to reach a cumulative emissions total. The relationship, which has been named the Transient Climate Response to Cumulative CO 2 Emissions (TCRE), gives rise to the concept of a 'carbon budget'. That is, a finite amount of carbon that can be burnt whilst remaining below some chosen global temperature change threshold, such as the 2.0 °C target set by the Paris Agreement. Here we show that the path-independence of TCRE arises from the partitioning ratio of anthropogenic carbon between the ocean and the atmosphere being almost the same as the partitioning ratio of enhanced radiative forcing between the ocean and space. That these ratios are so close in value is a coincidence unique to CO 2 . The simple model used here is underlain by many assumptions and simplifications but does reproduce key aspects of the climate system relevant to the path-independence of carbon budgets. Our results place TCRE and carbon budgets on firm physical foundations and therefore help validate the use of these metrics for climate policy.

Equilibrium radiative heating tables for Earth entry

NASA Astrophysics Data System (ADS)

Sutton, Kenneth; Hartung, Lin C.

1990-05-01

The recent resurgence of interest in blunt-body atmospheric entry for applications such as aeroassisted orbital transfer and planetary return has engendered a corresponding revival of interest in radiative heating. Radiative heating may be of importance in these blunt-body flows because of the highly energetic shock layer around the blunt nose. Sutton developed an inviscid, stagnation point, radiation coupled flow field code for investigating blunt-body atmospheric entry. The method has been compared with ground-based and flight data, and reasonable agreement has been found. To provide information for entry body studies in support of lunar and Mars return scenarios of interest in the 1970's, the code was exercised over a matrix of Earth entry conditions. Recently, this matrix was extended slightly to reflect entry vehicle designs of current interest. Complete results are presented.

Geology on a Sand Budget

ERIC Educational Resources Information Center

Kane, Jacqueline

2004-01-01

Earth science teachers know how frustrating it can be to spend hundreds of dollars on three-dimensional (3-D) models of Earth's geologic features, to use the models for only a few class periods. To avoid emptying an already limited science budget, the author states that teachers can use a simple alternative to the expensive 3-D models--sand. She…

Earth cloud, aerosol, and radiation explorer optical payload development status

NASA Astrophysics Data System (ADS)

Hélière, A.; Wallace, K.; Pereira do Carmo, J.; Lefebvre, A.

2017-09-01

The European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) are co-operating to develop as part of ESA's Living Planet Programme, the third Earth Explorer Core Mission, EarthCARE, with the ojective of improving the understanding of the processes involving clouds, aerosols and radiation in the Earth's atmosphere. EarthCARE payload consists of two active and two passive instruments: an ATmospheric LIDar (ATLID), a Cloud Profiling Radar (CPR), a Multi-Spectral Imager (MSI) and a Broad-Band Radiometer (BBR). The four instruments data are processed individually and in a synergetic manner to produce a large range of products, which include vertical profiles of aerosols, liquid water and ice, observations of cloud distribution and vertical motion within clouds, and will allow the retrieval of profiles of atmospheric radiative heating and cooling. MSI is a compact instrument with a 150 km swath providing 500 m pixel data in seven channels, whose retrieved data will give context to the active instrument measurements, as well as providing cloud and aerosol information. BBR measures reflected solar and emitted thermal radiation from the scene. Operating in the UV range at 355 nm, ATLID provides atmospheric echoes from ground to an altitude of 40 km. Thanks to a high spectral resolution filtering, the lidar is able to separate the relative contribution of aerosol and molecular scattering, which gives access to aerosol optical depth. Co-polarised and cross-polarised components of the Mie scattering contribution are measured on dedicated channels. This paper will provide a description of the optical payload implementation, the design and characterisation of the instruments.

Long Term Measurement of the Earth's Radiation Budget using a constellation of Broadband Radiometers hosted on Iridium NEXT

NASA Astrophysics Data System (ADS)

Gupta, Om Prakash; Thoma, Donald; Chaloner, Chris; Russell, Jacqueline; Simpson, Bill; Spilling, David; Morris, Nigel; Caldwell, Martin; Oneill, Alan

The WMO called for "bringing new missions to operational status" and that "ERB should be measured through a constellation of sensors". A unique opportu-nity exists to host a set of Earth Radiation Budget (ERB) sensors on the Iridium NEXT (NEXT) LEO constellation in a cost effective manner that can deliver these requirements. The NEXT constellation, with 66 interconnected satellites in 6 near polar orbiting planes, provides a unique platform for hosting a variety of Earth observation missions including ERB. Launches are planned to begin in 2014 through 2016. The ERB both drives and responds to global climate and monitoring it can provide much insight into the climate system and how it might be changing. A climate quality measurement of the ERB requires high absolute accuracy and excellent stability and a long-term (decades) data record in order to inform the debate about global warming. Measurement of the ERB in terms of the broadband reflected solar (0.3 to 4 µm) and emitted thermal (4 to 200 µm) components have been identified as high priority by the WMO for climate observations. High temporal resolution is the key advantage offered by the NEXT platform and can provide a great step forward in accurately monitoring the energy balance of the planet. The sensor we propose will consist of a broad band instrument and associated imager for scene identification and cloud classification. There is the chance to place two such sensors in each of six different orbital planes this will improve the product refresh time from currently 12 hours to 3 hours. The increased temporal resolution will allow direct measure-ment of the changes to the broadband radiances that result from rapidly varying components of the climate such as cloud and aerosol, and avoid the need of relying on narrow band sensors to infer such changes. Considering that the prediction of cloud response to climate change is still a major source of uncertainty; improved measurement of the cloud effect and

Analyses of earth radiation budget data from unrestricted broadband radiometers on the ESSA 7 satellite

NASA Technical Reports Server (NTRS)

Weaver, W. L.; House, F. B.

1979-01-01

Six months of data from the wide-field-of-view low resolution infrared radiometers on the Environmental Science Services Administration (ESSA) 7 satellite were analyzed. Earth emitted and earth reflected irradiances were computed at satellite altitude using data from a new in-flight calibration technique. Flux densitites and albedos were computed for the top of the earth's atmosphere. Monthly averages of these quantities over 100 latitude zones, each hemisphere, and the globe are presented for each month analyzed, and global distributions are presented for typical months. Emitted flux densities are generally lower and albedos higher than those of previous studies. This may be due, in part, to the fact that the ESSA 7 satellite was in a 3 p.m. Sun-synchronous orbit and some of the comparison data were obtained from satellites in 12 noon sun-synchronous orbits. The ESSA 7 detectors seem to smooth out spatial flux density variations more than scanning radiometers or wide-field-of-view fixed-plate detectors. Significant longitudinal and latitudinal variations of emitted flux density and albedo were identified in the tropics in a zone extending about + or - 25 deg in latitude.

Human response to high-background radiation environments on Earth and in space

NASA Astrophysics Data System (ADS)

Durante, M.; Manti, L.

2008-09-01

The main long-term objective of the space exploration program is the colonization of the planets of the Solar System. The high cosmic radiation equivalent dose rate represents an inescapable problem for the safe establishment of permanent human settlements on these planets. The unshielded equivalent dose rate on Mars ranges between 100 and 200 mSv/year, depending on the Solar cycle and altitude, and can reach values as high as 360 mSv/year on the Moon. The average annual effective dose on Earth is about 3 mSv, nearly 85% of which comes from natural background radiation, reduced to less than 1 mSv if man-made sources and the internal exposure to Rn daughters are excluded. However, some areas on Earth display anomalously high levels of background radiation, as is the case with thorium-rich monazite bearing sand deposits where values 200 400 times higher than the world average can be found. About 2% of the world’s population live above 3 km and receive a disproportionate 10% of the annual effective collective dose due to cosmic radiation, with a net contribution to effective dose by the neutron component which is 3 4 fold that at sea level. Thus far, epidemiological studies have failed to show any adverse health effects in the populations living in these terrestrial high-background radiation areas (HBRA), which provide an unique opportunity to study the health implications of an environment that, as closely as possibly achievable on Earth, resembles the chronic exposure of future space colonists to higher-than-normal levels of ionizing radiation. Chromosomal aberrations in the peripheral blood lymphocytes from the HBRA residents have been measured in several studies because chromosomal damage represents an early biomarker of cancer risk. Similar cytogenetic studies have been recently performed in a cohort of astronauts involved in single or repeated space flights over many years. The cytogenetic findings in populations exposed to high dose-rate background radiation

Clouds-radiation interactions in a general circulation model - Impact upon the planetary radiation balance

NASA Technical Reports Server (NTRS)

Smith, Laura D.; Vonder Haar, Thomas H.

1991-01-01

Simultaneously conducted observations of the earth radiation budget and the cloud amount estimates, taken during the June 1979 - May 1980 Nimbus 7 mission were used to show interactions between the cloud amount and raidation and to verify a long-term climate simulation obtained with the latest version of the NCAR Community Climate Model (CCM). The parameterization of the radiative, dynamic, and thermodynamic processes produced the mean radiation and cloud quantities that were in reasonable agreement with satellite observations, but at the expense of simulating their short-term fluctuations. The results support the assumption that the inclusion of the cloud liquid water (ice) variable would be the best mean to reduce the blinking of clouds in NCAR CCM.

Radiation from lightning return strokes over a finitely conducting earth

NASA Technical Reports Server (NTRS)

Le Vine, D. M.; Gesell, L.; Kao, Michael

1986-01-01

The effects of the conductivity of the earth on radiation from lightning return strokes are examined theoretically using a piecewise linear transmission line model for the return stroke. First, calculations are made of the electric field radiated during the return stroke, and then this electric field is used to compute the response of conventional AM radio receivers and electric field change systems during the return stroke. The calculations apply to the entire transient waveform (they are not restricted to the initial portions of the return stroke) and yield fast field changes and RF radiation in agreement with measurements made during real lightning. This research was motivated by measurements indicating that a time delay exists between the time of arrival of the fast electric field change and the RF radiation from first return strokes. The time delay is on the order of 20 microsec for frequencies in the HF-UHF range for lightning in Florida. The time delay is obtained theoretically in this paper. It occurs when both the effects of attenuation due to conductivity of the earth, and the finite velocity of propagation of the current pulse up the return stroke channel, are taken into account in the model.

Global Energy and Water Budgets in MERRA

NASA Technical Reports Server (NTRS)

Bosilovich, Michael G.; Robertson, Franklin R.; Chen, Junye

2010-01-01

Reanalyses, retrospectively analyzing observations over climatological time scales, represent a merger between satellite observations and models to provide globally continuous data and have improved over several generations. Balancing the Earth s global water and energy budgets has been a focus of research for more than two decades. Models tend to their own climate while remotely sensed observations have had varying degrees of uncertainty. This study evaluates the latest NASA reanalysis, called the Modern Era Retrospective-analysis for Research and Applications (MERRA), from a global water and energy cycles perspective. MERRA was configured to provide complete budgets in its output diagnostics, including the Incremental Analysis Update (IAU), the term that represents the observations influence on the analyzed states, alongside the physical flux terms. Precipitation in reanalyses is typically sensitive to the observational analysis. For MERRA, the global mean precipitation bias and spatial variability are more comparable to merged satellite observations (GPCP and CMAP) than previous generations of reanalyses. Ocean evaporation also has a much lower value which is comparable to observed data sets. The global energy budget shows that MERRA cloud effects may be generally weak, leading to excess shortwave radiation reaching the ocean surface. Evaluating the MERRA time series of budget terms, a significant change occurs, which does not appear to be represented in observations. In 1999, the global analysis increments of water vapor changes sign from negative to positive, and primarily lead to more oceanic precipitation. This change is coincident with the beginning of AMSU radiance assimilation. Previous and current reanalyses all exhibit some sensitivity to perturbations in the observation record, and this remains a significant research topic for reanalysis development. The effect of the changing observing system is evaluated for MERRA water and energy budget terms.

The NASA/GEWEX Surface Radiation Budget Release 4 Integrated Product: An Assessment of Improvements in Algorithms and Inputs

NASA Astrophysics Data System (ADS)

Stackhouse, P. W., Jr.; Cox, S. J.; Mikovitz, J. C.; Zhang, T.; Gupta, S. K.

2016-12-01

The NASA/GEWEX Surface Radiation Budget (SRB) project produces, validates and analyzes shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. The current release 3.0/3.1 consists of 1x1 degree radiative fluxes (available at gewex-srb.larc.nasa.gov) and is produced using the International Satellite Cloud Climatology Project (ISCCP) DX product for pixel level radiance and cloud information. This ISCCP DX product is subsampled to 30 km. ISCCP is currently recalibrating and reprocessing their entire data series, to be released as the H product series, with its highest resolution at 10km pixel resolution. The nine-fold increase in number of pixels will allow SRB to produce a higher resolution gridded product (e.g. 0.5 degree or higher), as well as the production of pixel-level fluxes. Other key input improvements include a detailed aerosol history using the Max Planck Institute Aerosol Climatology (MAC), temperature and moisture profiles from HIRS, and new topography, surface type, and snow/ice maps. Here we present results for the improved GEWEX Shortwave and Longwave algorithm (GSW and GLW) with new ISCCP data (for at least 5 years, 2005-2009), various other improved input data sets and incorporation of many additional internal SRB model improvements. We assess the radiative fluxes from new SRB products and contrast these at various resolutions. All these fluxes are compared to both surface measurements and to CERES SYN1Deg and EBAF data products for assessment of the effect of improvements. The SRB data produced will be released as part of the Release 4.0 Integrated Product that shares key input and output quantities with other GEWEX global products providing estimates of the Earth's global water and energy cycle (i.e., ISCCP, SeaFlux, LandFlux, NVAP, etc.).

Radiative Energy Budgets of Phototrophic Surface-Associated Microbial Communities and their Photosynthetic Efficiency Under Diffuse and Collimated Light.

PubMed

Lichtenberg, Mads; Brodersen, Kasper E; Kühl, Michael

2017-01-01

We investigated the radiative energy budgets of a heterogeneous photosynthetic coral reef sediment and a compact uniform cyanobacterial biofilm on top of coastal sediment. By combining electrochemical, thermocouple and fiber-optic microsensor measurements of O 2 , temperature and light, we could calculate the proportion of the absorbed light energy that was either dissipated as heat or conserved by photosynthesis. We show, across a range of different incident light regimes, that such radiative energy budgets are highly dominated by heat dissipation constituting up to 99.5% of the absorbed light energy. Highest photosynthetic energy conservation efficiency was found in the coral sediment under low light conditions and amounted to 18.1% of the absorbed light energy. Additionally, the effect of light directionality, i.e., diffuse or collimated light, on energy conversion efficiency was tested on the two surface-associated systems. The effects of light directionality on the radiative energy budgets of these phototrophic communities were not unanimous but, resulted in local spatial differences in heat-transfer, gross photosynthesis, and light distribution. The light acclimation index, E k , i.e., the irradiance at the onset of saturation of photosynthesis, was >2 times higher in the coral sediment compared to the biofilm and changed the pattern of photosynthetic energy conservation under light-limiting conditions. At moderate to high incident irradiances, the photosynthetic conservation of absorbed energy was highest in collimated light; a tendency that changed in the biofilm under sub-saturating incident irradiances, where higher photosynthetic efficiencies were observed under diffuse light. The aim was to investigate how the physical structure and light propagation affected energy budgets and light utilization efficiencies in loosely organized vs. compact phototrophic sediment under diffuse and collimated light. Our results suggest that the optical properties and the

Radiative Energy Budgets of Phototrophic Surface-Associated Microbial Communities and their Photosynthetic Efficiency Under Diffuse and Collimated Light

PubMed Central

Lichtenberg, Mads; Brodersen, Kasper E.; Kühl, Michael

2017-01-01

We investigated the radiative energy budgets of a heterogeneous photosynthetic coral reef sediment and a compact uniform cyanobacterial biofilm on top of coastal sediment. By combining electrochemical, thermocouple and fiber-optic microsensor measurements of O2, temperature and light, we could calculate the proportion of the absorbed light energy that was either dissipated as heat or conserved by photosynthesis. We show, across a range of different incident light regimes, that such radiative energy budgets are highly dominated by heat dissipation constituting up to 99.5% of the absorbed light energy. Highest photosynthetic energy conservation efficiency was found in the coral sediment under low light conditions and amounted to 18.1% of the absorbed light energy. Additionally, the effect of light directionality, i.e., diffuse or collimated light, on energy conversion efficiency was tested on the two surface-associated systems. The effects of light directionality on the radiative energy budgets of these phototrophic communities were not unanimous but, resulted in local spatial differences in heat-transfer, gross photosynthesis, and light distribution. The light acclimation index, Ek, i.e., the irradiance at the onset of saturation of photosynthesis, was >2 times higher in the coral sediment compared to the biofilm and changed the pattern of photosynthetic energy conservation under light-limiting conditions. At moderate to high incident irradiances, the photosynthetic conservation of absorbed energy was highest in collimated light; a tendency that changed in the biofilm under sub-saturating incident irradiances, where higher photosynthetic efficiencies were observed under diffuse light. The aim was to investigate how the physical structure and light propagation affected energy budgets and light utilization efficiencies in loosely organized vs. compact phototrophic sediment under diffuse and collimated light. Our results suggest that the optical properties and the

An investigation of ESSA 7 radiation data for use in long-term earth energy experiments, phases 1 and 2

NASA Technical Reports Server (NTRS)

House, F. B.

1974-01-01

The results are presented of an investigation of ESSA 7 satellite radiation data for use in long-term earth energy experiments. Satellite systems for performing long-term earth radiation balance measurements over geographical areas, hemispheres, and the entire earth for periods of 10 to 30 years are examined. The ESSA 7 satellite employed plate and cone radiometers to measure earth albedo and emitted radiation. Each instrument had a black and white radiometer which discriminated the components of albedo and emitted radiation. Earth measurements were made continuously from ESSA 7 for ten months. The ESSA 7 raw data is processed to a point where it can be further analyzed for: (1) development of long-term earth energy experiments; and (2) document climate trends.

Solar UV Radiation and the Origin of Life on Earth

NASA Technical Reports Server (NTRS)

Heap, Sara R.; Hubeny, Ivan; Lanz, Thierry; Gaidos, Eric; Kasting, James; Fisher, Richard R. (Technical Monitor)

2000-01-01

We have started a comprehensive, interdisciplinary study of the influence of solar ultraviolet radiation on the atmosphere of of the early Earth. We plan to model the chemistry of the Earth atmosphere during its evolution, using observed UV flux distributions of early solar analogs as boundary conditions in photochemical models of the Earth's atmosphere. The study has four distinct but interlinked parts: (1) Establishing the radiation of the early Sun; (2) Determining the photochemistry of the early Earth's atmosphere; (3) Estimating the rates of H2 loss from the atmosphere; and (4) Ascertaining how sensitive is the photochemistry to the metallicity of the Sun. We are currently using STIS and EUVE to obtain high-quality far-UV and extreme-UV observations of three early-solar analogs. We will perform a detailed non-LTE study of each stars, and construct theoretical model photosphere, and an empirical model chromospheres, which can be used to extrapolate the continuum to the Lyman continuum region. Given a realistic flux distribution of the early Sun, we will perform photochemical modeling of weakly reducing primitive atmospheres to determine the lifetime and photochemistry of CH4. In particular, we will make estimates of the amount of CH4 present in the prebiotic atmosphere, and estimate the atmospheric CH4 concentration during the Late Archean (2.5-3.0 b.y. ago) and determine whether it would have been sufficiently abundant to help offset reduced solar luminosity at that time. Having obtained a photochemical model, we will solve for the concentrations of greenhouse gasses and important pre-biotic molecules, and perform a detailed radiative transfer calculations to compute the UV flux reaching the surface.

Solar UV Radiation and the Origin of Life on Earth

NASA Technical Reports Server (NTRS)

Heap, S. R.; Gaidos, E.; Hubeny, I.; Lanz, T. M.; Fisher, Richard R. (Technical Monitor)

2001-01-01

We have embarked on a program aimed at understanding the atmosphere of the early Earth, because of its importance as a greenhouse, radiation shield, and energy source for life. Here, we give a progress report on the first phase of this program: to establish the UV radiation from the early Sun. We are presently obtaining ultraviolet spectra (STIS, FUSE, EUVE) of carefully selected nearby, young solar-type stars, which act as surrogates for the early Sun. We are currently making detailed non-LTE analyses of the spectra and constructing models of their photospheres + chromospheres. once validated, these models will allow us to extrapolate our theoretical spectra to unobserved spectral regions, and to proceed to the next step: to develop photochemical models of the pre-biotic and Archean atmosphere of the Earth.

Solar Radiation and Cloud Radiative Forcing in the Pacific Warm Pool Estimated Using TOGA COARE Measurements

NASA Technical Reports Server (NTRS)

Chou, Ming-Dah; Chou, Shu-Hsien; Zhao, Wenzhong

1999-01-01

The energy budget of the tropical western Pacific (TWP) is particularly important because this is one of the most energetic convection regions on the Earth. Nearly half of the solar radiation incident at the top of atmosphere is absorbed at the surface and only about 22% absorbed in the atmosphere. A large portion of the excess heat absorbed at the surface is transferred to the atmosphere through evaporation, which provides energy and water for convection and precipitation. The western equatorial Pacific is characterized by the highest sea surface temperature (SST) and heaviest rainfall in the world ocean. A small variation of SST associated with the eastward shift of the warm pool during El-Nino/Souther Oscillation changes the atmospheric circulation pattern and affects the global climate. In a study of the TWP surface heat and momentum fluxes during the Tropical Ocean and Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) Intensive observing period (IOP) from November 1992 to February have found that the solar radiation is the most important component of the surface energy budget, which undergoes significant temporal and spatial variation. The variations are influenced by the two 40-50 days Madden Julian Oscillations (MJOs) which propagated eastward from the Indian Ocean to the Central Pacific during the IOP. The TWP surface solar radiation during the COARE IOP was investigated by a number of studies. In addition, the effects of clouds on the solar heating of the atmosphere in the TWP was studied using energy budget analysis. In this study, we present some results of the TWP surface solar shortwave or SW radiation budget and the effect of clouds on the atmospheric solar heating using the surface radiation measurements and Japan's Geostationary Meteorological Satellite 4 radiance measurements during COARE IOP.

WATER FORMATION IN THE UPPER ATMOSPHERE OF THE EARLY EARTH

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

Fleury, Benjamin; Carrasco, Nathalie; Marcq, Emmanuel

2015-07-10

The water concentration and distribution in the early Earth's atmosphere are important parameters that contribute to the chemistry and the radiative budget of the atmosphere. If the atmosphere above the troposphere is generally considered as dry, photochemistry is known to be responsible for the production of numerous minor species. Here we used an experimental setup to study the production of water in conditions simulating the chemistry above the troposphere of the early Earth with an atmospheric composition based on three major molecules: N{sub 2}, CO{sub 2}, and H{sub 2}. The formation of gaseous products was monitored using infrared spectroscopy. Watermore » was found as the major product, with approximately 10% of the gas products detected. This important water formation is discussed in the context of the early Earth.« less

Radiation measurements from polar and geosynchronous satellites

NASA Technical Reports Server (NTRS)

Vonderhaar, T. H.

1973-01-01

During the 1960's, radiation budget measurements from satellites have allowed quantitative study of the global energetics of our atmosphere-ocean system. A continuing program is planned, including independent measurement of the solar constant. Thus far, the measurements returned from two basically different types of satellite experiments are in agreement on the long term global scales where they are most comparable. This fact, together with independent estimates of the accuracy of measurement from each system, shows that the energy exchange between earth and space is now measured better than it can be calculated. Examples of application of the radiation budget data were shown. They can be related to the age-old problem of climate change, to the basic question of the thermal forcing of our circulation systems, and to the contemporary problems of local area energetics and computer modeling of the atmosphere.

Fate of Earth Microbes on Mars: UV Radiation Effects

NASA Technical Reports Server (NTRS)

Cockell, Charles

2000-01-01

A radiative transfer model is used to quantitatively investigate aspects of the martian ultraviolet radiation environment. Biological action spectra for DNA inactivation are used to estimate biologically effective irradiances for the martian surface under cloudless skies. Although the present-day martian UV flux is similar to early earth and thus may not be a limitation to life in the evolutionary context, it is a constraint to an unadapted biota and will rapidly kill spacecraft-borne microbes not covered by a martian dust layer. Here calculations for loss of microbial viability on the Pathfinder and Polar lander spacecraft are presented and the effects of martian dust on loss of viability are discussed. Details of the radiative transfer model are presented.

Fate of Earth Microbes on Mars -- UV Radiation Effects

NASA Technical Reports Server (NTRS)

Cockell, Charles

2000-01-01

A radiative transfer model is used to quantitatively investigate aspects of the martian ultraviolet radiation environment. Biological action spectra for DNA inactivation are used to estimate biologically effective irradiances for the martian surface under cloudless skies. Although the present-day martian UV flux is similar to early earth and thus may not be a limitation to life in the evolutionary context, it is a constraint to an unadapted biota and will rapidly kill spacecraft-borne microbes not covered by a martian dust layer. Here calculations for loss of microbial viability on the Pathfinder and Polar lander spacecraft are presented and the effects of martian dust on loss of viability are discussed. Details of the radiative transfer model are presented.

Budget Increases Proposed for NOAA and Energy Department

NASA Astrophysics Data System (ADS)

Showstack, Randy

2009-05-01

In addition to the Obama administration's proposed budget increases for NASA, the Environmental Protection Agency, and the U.S. Geological Survey (see Eos, 90(10), 83, 2009, and 90(20), 175, 2009), other federal Earth and space science agencies also would receive boosts in the proposed fiscal year (FY) 2010 budget. The proposed budget comes on top of the 2009 American Recovery and Reinvestment Act's (ARRA) US$18.3 billion in stimulus spending for research and development that can be apportioned between the FY 2009 and FY 2010 budgets. This news item focuses on the budget proposals for the National Oceanic and Atmospheric Administration (NOAA) and the Department of Energy (DOE). Next week, Eos will look at the budget proposal for the National Science Foundation.

Exploring the Earth's Radiation Belts

NASA Astrophysics Data System (ADS)

Daglis, I. A.; Anastasiadis, A.; Chatzichristou, E. T.; Ropokis, G.; Giannakis, O.

2012-09-01

We present the outreach efforts of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, intended to provide the general public with simplified information concerning the scientific objectives of the project, its focus and its expected outcomes. MAARBLE involves monitoring of the geospace environment through space and ground-based observations, in order to understand various aspects of the radiation belts (torus-shaped regions encircling the Earth, in which high-energy charged particles are trapped by the geomagnetic field), which have direct impact on human endeavors in space (spacecraft and astronauts exposure). The public outreach website of MAARBLE, besides regular updates with relevant news, also employs a variety of multimedia (image and video galleries) and impressive sounds of space (characteristic sounds such as whistlers or tweeks) related to very low and ultra low frequency (VLF/ULF) electromagnetic waves. It also provides links to some of the most interesting relevant educational activities, including those at partner institutions such as the Institute of Geophysics and Planetary Physics at UCLA, the University of Alberta, the Swedish Institute of Space Physics and the Institute of Atmospheric Physics of the Academy of Sciences of the Czech Republic.

Extreme enhancements and depletions of relativistic electrons in Earth's radiation belts

NASA Astrophysics Data System (ADS)

Turner, D. L.; Claudepierre, S. G.; O'Brien, T. P., III; Fennell, J. F.; Blake, J. B.; Baker, D. N.; Jaynes, A. N.; Morley, S.; Geoffrey, R.

2015-12-01

Earth's electron radiation belts consist of toroidal zones in near-Earth space characterized by intense levels of relativistic electrons with distinct energy-dependent boundaries. It has been known for decades that the outer electron radiation belt is highly variable, with electron intensities varying by orders of magnitude on timescales ranging from minutes to years. Now, we are gaining much insight into the nature of this extreme variability thanks to the unprecedented number of observatories capable of measuring radiation belt electrons, the most recent of which is NASA's Van Allen Probes mission. In this presentation, we analyze and review several of the most extreme events observed in Earth's outer radiation belt. We begin with very sudden and strong enhancements of the outer radiation belt that can result in several orders of magnitude enhancements of electron intensities up to several MeV that sometimes occur in less than one day. We compare and contrast two of the most extreme cases of sudden and strong enhancements from the Van Allen Probes era, 08-09 October 2012 and 17-18 March 2015, and review evidence of the dominant acceleration mechanism in each event. Sudden enhancements of the radiation belts can also occur from injections by interplanetary shocks impacting the magnetosphere, such as occurred on 24 March 1991. We compare shock characteristics from previous injection events to those from the Van Allen Probes era to investigate why none of the interplanetary shocks since September 2012 have caused MeV electron injections into the slot region and inner radiation belt, which has surprisingly been devoid of measurable quantities of >~1 MeV electrons throughout the Van Allen Probes era. Our last topic concerns loss processes. We discuss drastic loss events, known as "flux dropouts", and present evidence that these loss events can eliminate the vast majority of relativistic electrons in the outer radiation belt on time scales of only a few hours. We

Radiation shelter effectiveness beyond the earth magnetosphere

NASA Astrophysics Data System (ADS)

Shurshakov, V. A.; Benghin, V. V.; Kolomensky, A. V.; Petrov, V. M.

Solar energetic particles (SEP) and galactic cosmic rays are known to be the sources of radiation hazard for missions beyond the Earth magnetosphere. An additionally shielded compartment of the mission spacecraft, called usually the radiation shelter, is considered as an important part of the radiation safety system. The shielding of the radiation shelter must be at least a few times higher than that of the remaining compartments. The mission crewmembers are supposed to stay in the radiation shelter for relatively short time of less than a day or two during SEP events only. A job-oriented radiation monitoring system (RMS) should be used on board the Martian mission spacecraft to provide the crew with necessary prediction information concerning the onset of a large SEP event. The information should be obtained independently of the ground-based support services and, hence, should be derived from online measurements of the dynamics of soft X-rays and charged energetic particles using the RMS sensors. As a result, the signal for the spacecrew members to go to the shelter gets somewhat delayed with respect to the SEP event onset, so that they appear to stay outside the shelter for some time during the event. The dependence of the crew-received dose on the SEP event prediction lag has been analyzed in terms of the standard SEP dynamics model for a typical 500-day Martian mission scenario. The Martian mission dose simulations have demonstrated a high efficiency of the radiation shelter despite the unavoidable lag of the RMS prediction signal.

On the Utilization of Ice Flow Models and Uncertainty Quantification to Interpret the Impact of Surface Radiation Budget Errors on Estimates of Greenland Ice Sheet Surface Mass Balance and Regional Estimates of Mass Balance

NASA Astrophysics Data System (ADS)

Schlegel, N.; Larour, E. Y.; Gardner, A. S.; Lang, C.; Miller, C. E.; van den Broeke, M. R.

2016-12-01

How Greenland ice flow may respond to future increases in surface runoff and to increases in the frequency of extreme melt events is unclear, as it requires detailed comprehension of Greenland surface climate and the ice sheet's sensitivity to associated uncertainties. With established uncertainty quantification tools run within the framework of Ice Sheet System Model (ISSM), we conduct decadal-scale forward modeling experiments to 1) quantify the spatial resolution needed to effectively force distinct components of the surface radiation budget, and subsequently surface mass balance (SMB), in various regions of the ice sheet and 2) determine the dynamic response of Greenland ice flow to variations in components of the net radiation budget. The Glacier Energy and Mass Balance (GEMB) software is a column surface model (1-D) that has recently been embedded as a module within ISSM. Using the ISSM-GEMB framework, we perform sensitivity analyses to determine how perturbations in various components of the surface radiation budget affect model output; these model experiments allow us predict where and on what spatial scale the ice sheet is likely to dynamically respond to changes in these parameters. Preliminary results suggest that SMB should be forced at at least a resolution of 23 km to properly capture dynamic ice response. In addition, Monte-Carlo style sampling analyses reveals that the areas with the largest uncertainty in mass flux are located near the equilibrium line altitude (ELA), upstream of major outlet glaciers in the North and West of the ice sheet. Sensitivity analysis indicates that these areas are also the most vulnerable on the ice sheet to persistent, far-field shifts in SMB, suggesting that continued warming, and upstream shift in the ELA, are likely to result in increased velocities, and consequentially SMB-induced thinning upstream of major outlet glaciers. Here, we extend our investigation to consider various components of the surface radiation

The Global Energy Budget.

ERIC Educational Resources Information Center

Jax, Daniel W.

1992-01-01

Presents a lesson plan about greenhouse effect and global warming. Includes diagrams and graphs from which students are asked to make inferences. Provides background information about how energy enters and leaves the earth system, the energy budget, consequences of obstructing the energy balance, and the greenhouse effect. (three references) (MCO)

Calculation of TIR Canopy Hot Spot and Implications for Earth Radiation Budget

NASA Technical Reports Server (NTRS)

Smith, J. A.; Ballard, J. R., Jr.

2000-01-01

Using a 3-D model for thermal infrared exitance and the Lowtran 7 atmospheric radiative transfer model, we compute the variation in brightness temperature with view direction and, in particular, the canopy thermal hot spot. We then perform a sensitivity analysis of surface energy balance components for a nominal case using a simple SVAT model given the uncertainty in canopy temperature arising from the thermal hot spot effect. Canopy thermal hot spot variations of two degrees C lead to differences of plus or minus 24% in the midday available energy.

Assessment of NASA GISS CMIP5 ModelE simulated clouds and TOA radiation budgets using satellite observations over the southern mid-latitudes

NASA Astrophysics Data System (ADS)

Stanfield, Ryan Evan

Past, current, and future climates have been simulated by the National Aeronautics and Space Administration (NASA) Goddard Institute for Space Studies (GISS) ModelE Global Circulation Model (GCM) and summarized by the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC, AR4). New simulations from the updated CMIP5 version of the NASA GISS ModelE GCM were recently released to the public community during the summer of 2011 and will be included in the upcoming IPCC AR5 ensemble of simulations. Due to the recent nature of these simulations, they have not yet been extensively validated against observations. To assess the NASA GISS-E2-R GCM, model simulated clouds and cloud properties are compared to observational cloud properties derived from the Clouds and Earth's Radiant Energy System (CERES) project using MODerate Resolution Imaging Spectroradiometer (MODIS) data for the period of March 2000 through December 2005. Over the 6-year period, the global average modeled cloud fractions are within 1% of observations. However, further study however shows large regional biases between the GCM simulations and CERES-MODIS observations. The southern mid-latitudes (SML) were chosen as a focus region due to model errors across multiple GCMs within the recent phase 5 of the Coupled Model Intercomparison Project (CMIP5). Over the SML, the GISS GCM undersimulates total cloud fraction over 20%, but oversimulates total water path by 2 g m-2. Simulated vertical cloud distributions over the SML when compared to both CERES-MODIS and CloudSat/CALIPSO observations show a drastic undersimulation of low level clouds by the GISS GCM, but higher fractions of thicker clouds. To assess the impact of GISS simulated clouds on the TOA radiation budgets, the modeled TOA radiation budgets are compared to CERES EBAF observations. Because modeled low-level cloud fraction is much lower than observed over the SML, modeled reflected shortwave (SW) flux at the TOA is 13 W m -2 lower and

Mitigation of Earth-asteroid collisions via explosive, intense radiation sources

NASA Astrophysics Data System (ADS)

Miles, Aaron; Sanders, James

2005-10-01

The Universe is continually producing astrophysical explosions that generate intense bursts of electromagnetic and particle radiation. Interaction of this radiation with nearby objects can effect significant changes to their dynamics through a variety of processes including ionization, ablation, and shock generation. The next time a large asteroid or comet is found to be approaching the Earth on an impact trajectory, humans may find it prudent to mimic nature by using the most intense radiation sources available to alter the incoming object's trajectory and avert a catastrophic collision. With this in mind, we consider the effect of nuclear explosives on nearby would-be Earth impactors. Neutrons and x-rays produced in the explosion are deposited in a thin layer of the asteroid's surface, resulting in ablation and shock and thereby imparting a deflection velocity. A Monte Carlo code is used for radiation transport and energy deposition, while the subsequent dynamic evolution of the asteroid is followed with the hydrodynamics code CALE. We consider the dependence of the deflection velocity on the source energy and spectrum, the asteroid or comet composition, and the standoff distance between the target and the source. This work was performed under the auspices of the U. S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

Evidence for Solar Cycle Influence on the Infrared Energy Budget and Radiative Cooling of the Thermosphere

NASA Technical Reports Server (NTRS)

Mlynczak, Martin G.; Martin-Torres, F. Javier; Marshall, B. Thomas; Thompson, R. Earl; Williams, Joshua; Turpin, TImothy; Kratz, D. P.; Russell, James M.; Woods, Tom; Gordley, Larry L.

2007-01-01

We present direct observational evidence for solar cycle influence on the infrared energy budget and radiative cooling of the thermosphere. By analyzing nearly five years of data from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, we show that the annual mean infrared power radiated by the nitric oxide (NO) molecule at 5.3 m has decreased by a factor of 2.9. This decrease is correlated (r = 0.96) with the decrease in the annual mean F10.7 solar index. Despite the sharp decrease in radiated power (which is equivalent to a decrease in the vertical integrated radiative cooling rate), the variability of the power as given in the standard deviation of the annual means remains approximately constant. A simple relationship is shown to exist between the infrared power radiated by NO and the F10.7 index, thus providing a fundamental relationship between solar activity and the thermospheric cooling rate for use in thermospheric models. The change in NO radiated power is also consistent with changes in absorbed ultraviolet radiation over the same time period.

Particle Radiation Sources, Propagation and Interactions in Deep Space, at Earth, the Moon, Mars, and Beyond: Examples of Radiation Interactions and Effects

NASA Astrophysics Data System (ADS)

Schwadron, Nathan A.; Cooper, John F.; Desai, Mihir; Downs, Cooper; Gorby, Matt; Jordan, Andrew P.; Joyce, Colin J.; Kozarev, Kamen; Linker, Jon A.; Mikíc, Zoran; Riley, Pete; Spence, Harlan E.; Török, Tibor; Townsend, Lawrence W.; Wilson, Jody K.; Zeitlin, Cary

2017-11-01

Particle radiation has significant effects for astronauts, satellites and planetary bodies throughout the Solar System. Acute space radiation hazards pose risks to human and robotic exploration. This radiation also naturally weathers the exposed surface regolith of the Moon, the two moons of Mars, and other airless bodies, and contributes to chemical evolution of planetary atmospheres at Earth, Mars, Venus, Titan, and Pluto. We provide a select review of recent areas of research covering the origin of SEPs from coronal mass ejections low in the corona, propagation of events through the solar system during the anomalously weak solar cycle 24 and important examples of radiation interactions for Earth, other planets and airless bodies such as the Moon.

Features of Afterbody Radiative Heating for Earth Entry

NASA Technical Reports Server (NTRS)

Johnston, Christopher O.; Brandis, Aaron

2014-01-01

Radiative heating is identified as a major contributor to afterbody heating for Earth entry capsules at velocities above 10 km/s. Because of rate-limited electron-ion recombination processes, a large fraction of the electronically-excited N and O atoms produced in the high temperature/pressure forebody remain as they expand into the afterbody region, which results in significant afterbody radiation. Large radiative heating sensitivities to electron-impact ionization rates and escape factors are identified. Ablation products from a forebody ablator are shown to increase the afterbody radiation by as much as 40%. The tangent-slab radiation transport approach is shown to over-predict the radiative flux by as much as 40% in the afterbody, therefore making the more computationally expensive ray-tracing approach necessary for accurate radiative flux predictions. For the Stardust entry, the afterbody radiation is predicted to be nearly twice as large as the convective heating during the peak heating phase of the trajectory. Comparisons between simulations and the Stardust Echelle observation measurements, which are shown to be dominated by afterbody emission, indicate agreement within 20% for various N and O lines. Similarly, calorimeter measurements from the Fire II experiment are identified as a source of validation data for afterbody radiation. For the afterbody calorimeter measurement closest to the forebody, which experiences the largest afterbody radiative heating component, the convective heating alone is shown to under-predict the measurement, even for the fullycatalytic assumption. Agreement with the measurements is improved with the addition of afterbody radiation. These comparisons with Stardust and Fire II measurements provide validation that the significant afterbody radiation values proposed in this work are legitimate.

Earth Radiation Imbalance from a Constellation of 66 Iridium Satellites: Climate Science Aspects

NASA Technical Reports Server (NTRS)

Wiscombe, W.; Chiu, CJ. Y.

2012-01-01

The "global warming hiatus" since the 1998 El Nino, highlighted by Meehl et al., and the resulting "missing energy" problem highlighted by Trenberth et al., has opened the door to a more fundamental view of climate change than mere surface air temperature. That new view is based on two variables which are strongly correlated: the rate of change of ocean heat content d(OHC)/dt; and Earth Radiation Imbalance (ERI) at the top of the atmosphere, whose guesstimated range is 0.4 to 0.9 Watts per square meters (this imbalance being mainly due to increasing CO2). The Argo float array is making better and better measurements of OHC. But existing satellite systems cannot measure ERI to even one significant digit. So, climate model predictions of ERI are used in place of real measurements of it, and the satellite data are tuned to the climate model predictions. Some oceanographers say "just depend on Argo for understanding the global warming hiatus and the missing energy", but we don't think this is a good idea because d(OHC)/dt and ERI have different time scales and are never perfectly correlated. We think the ERB community needs to step up to measuring ERI correctly, just as oceanographers have deployed Argo to measure OHC correctly. This talk will overview a proposed constellation of 66 Earth radiation budget instruments, hosted on Iridium satellites, that will actually be able to measure ERI to at least one significant digit, thus enabling a crucial test of climate models. This constellation will also be able to provide ERI at two-hourly time scales and 500-km spatial scales without extrapolations from uncalibrated narrowband geostationary instruments, using the highly successful methods of GRACE to obtain spatial resolution. This high time resolution would make ERI a synoptic variable like temperature, and allow studies of ERI's response to fast-evolving phenomena like dust storms and hurricanes and even brief excursions of Total Solar Irradiance. Time permitting, we

Simulation studies of wide and medium field of view earth radiation data analysis

NASA Technical Reports Server (NTRS)

Green, R. N.

1978-01-01

A parameter estimation technique is presented to estimate the radiative flux distribution over the earth from radiometer measurements at satellite altitude. The technique analyzes measurements from a wide field of view (WFOV), horizon to horizon, nadir pointing sensor with a mathematical technique to derive the radiative flux estimates at the top of the atmosphere for resolution elements smaller than the sensor field of view. A computer simulation of the data analysis technique is presented for both earth-emitted and reflected radiation. Zonal resolutions are considered as well as the global integration of plane flux. An estimate of the equator-to-pole gradient is obtained from the zonal estimates. Sensitivity studies of the derived flux distribution to directional model errors are also presented. In addition to the WFOV results, medium field of view results are presented.

The Surface Radiation Budget over Oceans and Continents.

NASA Astrophysics Data System (ADS)

Garratt, J. R.; Prata, A. J.; Rotstayn, L. D.; McAvaney, B. J.; Cusack, S.

1998-08-01

An updated evaluation of the surface radiation budget in climate models (1994-96 versions; seven datasets available, with and without aerosols) and in two new satellite-based global datasets (with aerosols) is presented. All nine datasets capture the broad mean monthly zonal variations in the flux components and in the net radiation, with maximum differences of some 100 W m2 occurring in the downwelling fluxes at specific latitudes. Using long-term surface observations, both from land stations and the Pacific warm pool (with typical uncertainties in the annual values varying between ±5 and 20 W m2), excess net radiation (RN) and downwelling shortwave flux density (So) are found in all datasets, consistent with results from earlier studies [for global land, excesses of 15%-20% (12 W m2) in RN and about 12% (20 W m2) in So]. For the nine datasets combined, the spread in annual fluxes is significant: for RN, it is 15 (50) W m2 over global land (Pacific warm pool) in an observed annual mean of 65 (135) W m2; for So, it is 25 (60) W m2 over land (warm pool) in an annual mean of 176 (197) W m2.The effects of aerosols are included in three of the authors' datasets, based on simple aerosol climatologies and assumptions regarding aerosol optical properties. They offer guidance on the broad impact of aerosols on climate, suggesting that the inclusion of aerosols in models would reduce the annual So by 15-20 W m2 over land and 5-10 W m2 over the oceans. Model differences in cloud cover contribute to differences in So between datasets; for global land, this is most clearly demonstrated through the effects of cloud cover on the surface shortwave cloud forcing. The tendency for most datasets to underestimate cloudiness, particularly over global land, and possibly to underestimate atmospheric water vapor absorption, probably contributes to the excess downwelling shortwave flux at the surface.

Orbital measurements of the Earth's radiation budget during the first decade of the space program

NASA Technical Reports Server (NTRS)

Bandeen, W. R.

1982-01-01

The instrumentation and data analysis methods applied to data from the Explorer 7, TIROS 2, 3, 4, and 7, and Nimbus 2 and 3 experimental satellites are summarized. Problems encountered in analyzing these data included: determining the value of the solar constant, inaccuracies introduced by degradation of the sensors in orbit, the need to infer the total reflected and emitted radiation from filtered measurements, the development of corrections for anisotropy in order to determine the outgoing flux densities at the moment of measurement, and the development of corrections to account for diurnal variability. The corrections for long- and shortwave anisotropy and historical determinations of the solar constant and albedo are treated in detail. These early measurements indicated that the planetary albedo was lower, the emitted radiation higher, and the equator-to-pole gradient of net radiation greater than previously supposed.

Investigation of Non-Equilibrium Radiation for Earth Entry

NASA Technical Reports Server (NTRS)

Brandis, A. M.; Johnston, C. O.; Cruden, B. A.

2016-01-01

For Earth re-entry at velocities between 8 and 11.5 km/s, the accuracy of NASA's computational uid dynamic and radiative simulations of non-equilibrium shock layer radiation is assessed through comparisons with measurements. These measurements were obtained in the NASA Ames Research Center's Electric Arc Shock Tube (EAST) facility. The experiments were aimed at measuring the spatially and spectrally resolved radiance at relevant entry conditions for both an approximate Earth atmosphere (79% N2 : 21% O2 by mole) as well as a more accurate composition featuring the trace species Ar and CO2 (78.08% N2 : 20.95% O2 : 0.04% CO2 : 0.93% Ar by mole). The experiments were configured to target a wide range of conditions, of which shots from 8 to 11.5 km/s at 0.2 Torr (26.7 Pa) are examined in this paper. The non-equilibrium component was chosen to be the focus of this study as it can account for a significant percentage of the emitted radiation for Earth re-entry, and more importantly, non-equilibrium has traditionally been assigned a large uncertainty for vehicle design. The main goals of this study are to present the shock tube data in the form of a non-equilibrium metric, evaluate the level of agreement between the experiment and simulations, identify key discrepancies and to examine critical aspects of modeling non-equilibrium radiating flows. Radiance pro les integrated over discreet wavelength regions, ranging from the Vacuum Ultra Violet (VUV) through to the Near Infra-Red (NIR), were compared in order to maximize both the spectral coverage and the number of experiments that could be used in the analysis. A previously defined non-equilibrium metric has been used to allow comparisons with several shots and reveal trends in the data. Overall, LAURA/HARA is shown to under-predict EAST by as much as 40% and over-predict by as much as 12% depending on the shock speed. DPLR/NEQAIR is shown to under-predict EAST by as much as 50% and over-predict by as much as 20% depending

Incorporation of multiple cloud layers for ultraviolet radiation modeling studies

NASA Technical Reports Server (NTRS)

Charache, Darryl H.; Abreu, Vincent J.; Kuhn, William R.; Skinner, Wilbert R.

1994-01-01

Cloud data sets compiled from surface observations were used to develop an algorithm for incorporating multiple cloud layers into a multiple-scattering radiative transfer model. Aerosol extinction and ozone data sets were also incorporated to estimate the seasonally averaged ultraviolet (UV) flux reaching the surface of the Earth in the Detroit, Michigan, region for the years 1979-1991, corresponding to Total Ozone Mapping Spectrometer (TOMS) version 6 ozone observations. The calculated UV spectrum was convolved with an erythema action spectrum to estimate the effective biological exposure for erythema. Calculations show that decreasing the total column density of ozone by 1% leads to an increase in erythemal exposure by approximately 1.1-1.3%, in good agreement with previous studies. A comparison of the UV radiation budget at the surface between a single cloud layer method and a multiple cloud layer method presented here is discussed, along with limitations of each technique. With improved parameterization of cloud properties, and as knowledge of biological effects of UV exposure increase, inclusion of multiple cloud layers may be important in accurately determining the biologically effective UV budget at the surface of the Earth.

Parameter estimation applied to Nimbus 6 wide-angle longwave radiation measurements

NASA Technical Reports Server (NTRS)

Green, R. N.; Smith, G. L.

1978-01-01

A parameter estimation technique was used to analyze the August 1975 Nimbus 6 Earth radiation budget data to demonstrate the concept of deconvolution. The longwave radiation field at the top of the atmosphere is defined from satellite data by a fifth degree and fifth order spherical harmonic representation. The variations of the major features of the radiation field are defined by analyzing the data separately for each two-day duty cycle. A table of coefficient values for each spherical harmonic representation is given along with global mean, gradients, degree variances, and contour plots. In addition, the entire data set is analyzed to define the monthly average radiation field.

Aggregating Hydrometeorological Data from International Monitoring Networks Across Earth's Largest Lake System to Quantify Uncertainty in Historical Water Budget Records, Improve Regional Water Budget Projections, and Differentiate Drivers Behind a Recent Record-Setting Surge in Water Levels

NASA Astrophysics Data System (ADS)

Gronewold, A.; Bruxer, J.; Smith, J.; Hunter, T.; Fortin, V.; Clites, A. H.; Durnford, D.; Qian, S.; Seglenieks, F.

2015-12-01

Resolving and projecting the water budget of the North American Great Lakes basin (Earth's largest lake system) requires aggregation of data from a complex array of in situ monitoring and remote sensing products that cross an international border (leading to potential sources of bias and other inconsistencies), and are relatively sparse over the surfaces of the lakes themselves. Data scarcity over the surfaces of the lakes is a particularly significant problem because, unlike Earth's other large freshwater basins, the Great Lakes basin water budget is (on annual scales) comprised of relatively equal contributions from runoff, over-lake precipitation, and over-lake evaporation. Consequently, understanding drivers behind changes in regional water storage and water levels requires a data management framework that can reconcile uncertainties associated with data scarcity and bias, and propagate those uncertainties into regional water budget projections and historical records. Here, we assess the development of a historical hydrometeorological database for the entire Great Lakes basin with records dating back to the late 1800s, and describe improvements that are specifically intended to differentiate hydrological, climatological, and anthropogenic drivers behind recent extreme changes in Great Lakes water levels. Our assessment includes a detailed analysis of the extent to which extreme cold winters in central North America in 2013-2014 (caused by the anomalous meridional upper air flow - commonly referred to in the public media as the "polar vortex" phenomenon) altered the thermal and hydrologic regimes of the Great Lakes and led to a record setting surge in water levels between January 2014 and December 2015.

Fiber-optic thermometer application of thermal radiation from rare-earth end-doped SiO{sub 2} fiber

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

Katsumata, Toru, E-mail: katsumat@toyo.jp; Morita, Kentaro; Komuro, Shuji

2014-08-15

Visible light thermal radiation from SiO{sub 2} glass doped with Y, La, Ce, Pr, Nd, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu were studied for the fiber-optic thermometer application based on the temperature dependence of thermal radiation. Thermal radiations according to Planck's law of radiation are observed from the SiO{sub 2} fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu at the temperature above 1100 K. Thermal radiations due to f-f transitions of rare-earth ions are observed from the SiO{sub 2} fibers doped with Nd, Dy, Ho, Er, Tm, and Yb at the temperature above 900more » K. Peak intensities of thermal radiations from rare-earth doped SiO{sub 2} fibers increase sensitively with temperature. Thermal activation energies of thermal radiations by f-f transitions seen in Nd, Dy, Ho, Er, Tm, and Yb doped SiO{sub 2} fibers are smaller than those from SiO{sub 2} fibers doped with Y, La, Ce, Pr, Eu, Tb, and Lu. Thermal radiation due to highly efficient f-f transitions in Nd, Dy, Ho, Er, Tm, and Yb ions emits more easily than usual thermal radiation process. Thermal radiations from rare-earth doped SiO{sub 2} are potentially applicable for the fiber-optic thermometry above 900 K.« less

Global Surface Net-Radiation at 5 km from MODIS Terra

DOE PAGES

Verma, Manish; Fisher, Joshua; Mallick, Kaniska; ...

2016-09-06

Reliable and fine resolution estimates of surface net-radiation are required for estimating latent and sensible heat fluxes between the land surface and the atmosphere. However, currently, fine resolution estimates of net-radiation are not available and consequently it is challenging to develop multi-year estimates of evapotranspiration at scales that can capture land surface heterogeneity and are relevant for policy and decision-making. We developed and evaluated a global net-radiation product at 5 km and 8-day resolution by combining mutually consistent atmosphere and land data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Terra. Comparison with net-radiation measurements from 154 globally distributedmore » sites (414 site-years) from the FLUXNET and Surface Radiation budget network (SURFRAD) showed that the net-radiation product agreed well with measurements across seasons and climate types in the extratropics (Wilmott's index ranged from 0.74 for boreal to 0.63 for Mediterranean sites). Mean absolute deviation between the MODIS and measured net-radiation ranged from 38.0 ± 1.8 W.m -2 in boreal to 72.0 ± 4.1 W.m -2 in the tropical climates. The mean bias was small and constituted only 11%, 0.7%, 8.4%, 4.2%, 13.3%, and 5.4% of the mean absolute error in daytime net-radiation in boreal, Mediterranean, temperate-continental, temperate, semi-arid, and tropical climate, respectively. To assess the accuracy of the broader spatiotemporal patterns, we upscaled error-quantified MODIS net-radiation and compared it with the net-radiation estimates from the coarse spatial (1° x 1°) but high temporal resolution gridded net-radiation product from the Clouds and Earth's Radiant Energy System (CERES). Our estimates agreed closely with the net-radiation estimates from the CERES. Difference between the two was less than 10W.m -2 in 94% of the total land area. MODIS net-radiation product will be a valuable resource for the science community studying

Global Surface Net-Radiation at 5 km from MODIS Terra

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

Verma, Manish; Fisher, Joshua; Mallick, Kaniska

Reliable and fine resolution estimates of surface net-radiation are required for estimating latent and sensible heat fluxes between the land surface and the atmosphere. However, currently, fine resolution estimates of net-radiation are not available and consequently it is challenging to develop multi-year estimates of evapotranspiration at scales that can capture land surface heterogeneity and are relevant for policy and decision-making. We developed and evaluated a global net-radiation product at 5 km and 8-day resolution by combining mutually consistent atmosphere and land data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Terra. Comparison with net-radiation measurements from 154 globally distributedmore » sites (414 site-years) from the FLUXNET and Surface Radiation budget network (SURFRAD) showed that the net-radiation product agreed well with measurements across seasons and climate types in the extratropics (Wilmott's index ranged from 0.74 for boreal to 0.63 for Mediterranean sites). Mean absolute deviation between the MODIS and measured net-radiation ranged from 38.0 ± 1.8 W.m -2 in boreal to 72.0 ± 4.1 W.m -2 in the tropical climates. The mean bias was small and constituted only 11%, 0.7%, 8.4%, 4.2%, 13.3%, and 5.4% of the mean absolute error in daytime net-radiation in boreal, Mediterranean, temperate-continental, temperate, semi-arid, and tropical climate, respectively. To assess the accuracy of the broader spatiotemporal patterns, we upscaled error-quantified MODIS net-radiation and compared it with the net-radiation estimates from the coarse spatial (1° x 1°) but high temporal resolution gridded net-radiation product from the Clouds and Earth's Radiant Energy System (CERES). Our estimates agreed closely with the net-radiation estimates from the CERES. Difference between the two was less than 10W.m -2 in 94% of the total land area. MODIS net-radiation product will be a valuable resource for the science community studying

A Survey of Radiation Measurements Made Aboard Russian Spacecraft in Low-Earth Orbit

NASA Technical Reports Server (NTRS)

Benton, E. R.; Benton, E. V.

1999-01-01

The accurate prediction of ionizing radiation exposure in low-Earth orbit is necessary in order to minimize risks to astronauts, spacecraft and instrumentation. To this end, models of the radiation environment, the AP-8 trapped proton model and the AE-8 trapped electron model, have been developed for use by spacecraft designers and mission planners. It has been widely acknowledged for some time now by the space radiation community that these models possess some major shortcomings. Both models cover only a limited trapped particle energy region and predictions at low altitudes are extrapolated from higher altitude data. With the launch of the first components of the International Space Station with numerous constellations of low-Earth orbit communications satellites now being planned and deployed, the inadequacies of these trapped particle models need to be addressed. Efforts are now underway both in the U.S. and in Europe to refine the AP-8 and AE-8 trapped particle models. This report is an attempt to collect a significant fraction of data for use in validation of trapped radiation models at low altitudes.

Magnetic Local Time dependency in modeling of the Earth radiation belts

NASA Astrophysics Data System (ADS)

Herrera, Damien; Maget, Vincent; Bourdarie, Sébastien; Rolland, Guy

2017-04-01

For many years, ONERA has been at the forefront of the modeling of the Earth radiation belts thanks to the Salammbô model, which accurately reproduces their dynamics over a time scale of the particles' drift period. This implies that we implicitly assume an homogeneous repartition of the trapped particles along a given drift shell. However, radiation belts are inhomogeneous in Magnetic Local Time (MLT). So, we need to take this new coordinate into account to model rigorously the dynamical structures, particularly induced during a geomagnetic storm. For this purpose, we are working on both the numerical resolution of the Fokker-Planck diffusion equation included in the model and on the MLT dependency of physic-based processes acting in the Earth radiation belts. The aim of this talk is first to present the 4D-equation used and the different steps we used to build Salammbô 4D model before focusing on physical processes taken into account in the Salammbô code, specially transport due to convection electric field. Firstly, we will briefly introduce the Salammbô 4D code developped by talking about its numerical scheme and physic-based processes modeled. Then, we will focus our attention on the impact of the outer boundary condition (localisation and spectrum) at lower L∗ shell by comparing modeling performed with geosynchronous data from LANL-GEO satellites. Finally, we will discuss the prime importance of the convection electric field to the radial and drift transport of low energy particles around the Earth.

The Earth System's Missing Energy and Land Warming

NASA Astrophysics Data System (ADS)

Huang, S.; Wang, H.; Duan, W.

2013-05-01

The energy content of the Earth system is determined by the balance or imbalance between the incoming energy from solar radiation and the outgoing energy of terrestrial long wavelength radiation. Change in the Earth system energy budget is the ultimate cause of global climate change. Satellite data show that there is a small yet persistent radiation imbalance at the top-of-atmosphere such that Earth has been steadily accumulating energy, consistent with the theory of greenhouse effect. It is commonly believed [IPCC, 2001; 2007] that up to 94% of the energy trapped by anthropogenic greenhouse gases is absorbed by the upper several hundred meter thick layer of global oceans, with the remaining to accomplish ice melting, atmosphere heating, and land warming, etc. However, the recent measurements from ocean monitoring system indicated that the rate of oceanic heat uptake has not kept pace with the greenhouse heat trapping rate over the past years [Trenberth and Fasullo, Science, 328: 316-317, 2010]. An increasing amount of energy added to the earth system has become unaccounted for, or is missing. A recent study [Loeb et al., Nature Geoscience, 5:110-113, 2012] suggests that the missing energy may be located in the deep ocean down to 1,800 m. Here we show that at least part of the missing energy can be alternatively explained by the land mass warming. We argue that the global continents alone should have a share greater than 10% of the global warming energy. Although the global lands reflect solar energy at a higher rate, they use less energy for evaporation than do the oceans. Taken into accounts the terrestrial/oceanic differences in albedo (34% vs. 28%) and latent heat (27% vs. 58% of net solar radiation at the surface), the radiative energy available per unit surface area for storage or other internal processes is more abundant on land than on ocean. Despite that the lands cover only about 29% of the globe, the portion of global warming energy stored in the lands

The Role of Clear Sky Identification in the Study of Cloud Radiative Effects: Combine Analysis from ISCCP and the Scanner of Radiation Budget (ScaRaB)

NASA Technical Reports Server (NTRS)

Rossow, W. B.; Stubenrauch, C. J.; Briand, V.; Hansen, James E. (Technical Monitor)

2001-01-01

Since the effect of clouds on the earth's radiation balance is often estimated as the difference of net radiative fluxes at the top of the atmosphere between all situations and monthly averaged clear sky situations of the same regions, a reliable identification of clear sky is important for the study of cloud radiative effects. The Scanner for Radiation Balance (ScaRaB) radiometer on board the Russian Meteor-3/7 satellite provided earth radiation budget observations from March 1994 to February 1995 with two ERBE-Re broad-band longwave and shortwave channels. Two narrow-band channels, in the infrared atmospheric window and in the visible band, have been added to the ScaRaB instrument to improve the cloud scene identification. The International Satellite Cloud Climatology Project (ISCCP) method for cloud detection and determination of cloud and surface properties uses the same narrow-band channels as ScaRaB, but is employed to a collection of measurements at a better spatial resolution of about 5 km. By applying the original ISCCP algorithms to the ScaRaB data, the clear sky frequency is about 5% lower than the one over quasi-simultaneous original ISCCP data, an indication that the ISCCP cloud detection is quite stable. However, one would expect an about 10 to 20% smaller clear sky occurrence over the larger ScaRaB pixels. Adapting the ISCCP algorithms to the reduced spatial resolution of 60 km and to the different time sampling of the ScaRaB data leads therefore to a reduction of a residual cloud contamination. A sensitivity study with time-space collocated ScaRaB and original ISCCP data at a spatial resolution of 1deg longitude x 1deg latitude shows that the effect of clear sky identification method plays a higher role on the clear sky frequency and therefore on the statistics than on the zonal mean values of the clear sky fluxes. Nevertheless, the zonal outgoing longwave fluxes corresponding to ERBE clear sky are in general about 2 to 10 W/sq m higher than those

3D Radiative Transfer in Cloudy Atmospheres

NASA Astrophysics Data System (ADS)

Marshak, Alexander; Davis, Anthony

Developments in three-dimensional cloud radiation over the past few decades are assessed and distilled into this contributed volume. Chapters are authored by subject-matter experts who address a broad audience of graduate students, researchers, and anyone interested in cloud-radiation processes in the solar and infrared spectral regions. After two introductory chapters and a section on the fundamental physics and computational techniques, the volume extensively treats two main application areas: the impact of clouds on the Earth's radiation budget, which is an essential aspect of climate modeling; and remote observation of clouds, especially with the advanced sensors on current and future satellite missions. http://www.springeronline.com/alert/article?a=3D1_1fva7w_1j826l_41z_6

Space Weather Effects in the Earth's Radiation Belts

NASA Astrophysics Data System (ADS)

Baker, D. N.; Erickson, P. J.; Fennell, J. F.; Foster, J. C.; Jaynes, A. N.; Verronen, P. T.

2018-02-01

The first major scientific discovery of the Space Age was that the Earth is enshrouded in toroids, or belts, of very high-energy magnetically trapped charged particles. Early observations of the radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. Recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed many novel properties of the radiation belts, especially for electrons at highly relativistic and ultra-relativistic kinetic energies. In this review we summarize the space weather impacts of the radiation belts. We demonstrate that many remarkable features of energetic particle changes are driven by strong solar and solar wind forcings. Recent comprehensive data show broadly and in many ways how high energy particles are accelerated, transported, and lost in the magnetosphere due to interplanetary shock wave interactions, coronal mass ejection impacts, and high-speed solar wind streams. We also discuss how radiation belt particles are intimately tied to other parts of the geospace system through atmosphere, ionosphere, and plasmasphere coupling. The new data have in many ways rewritten the textbooks about the radiation belts as a key space weather threat to human technological systems.

Error budgets for the Exoplanet Starshade (Exo-S) probe-class mission study

NASA Astrophysics Data System (ADS)

Shaklan, Stuart B.; Marchen, Luis; Cady, Eric; Ames, William; Lisman, P. Douglas; Martin, Stefan R.; Thomson, Mark; Regehr, Martin

2015-09-01

Exo-S is a probe-class mission study that includes the Dedicated mission, a 30 m starshade co-launched with a 1.1 m commercial telescope in an Earth-leading deep-space orbit, and the Rendezvous mission, a 34 m starshade intended to work with a 2.4 m telescope in an Earth-Sun L2 orbit. A third design, referred to as the Rendezvous Earth Finder mission, is based on a 40 m starshade and is currently under study. This paper presents error budgets for the detection of Earth-like planets with each of these missions. The budgets include manufacture and deployment tolerances, the allowed thermal fluctuations and dynamic motions, formation flying alignment requirements, surface and edge reflectivity requirements, and the allowed transmission due to micrometeoroid damage.

Error Budgets for the Exoplanet Starshade (exo-s) Probe-Class Mission Study

NASA Technical Reports Server (NTRS)

Shaklan, Stuart B.; Marchen, Luis; Cady, Eric; Ames, William; Lisman, P. Douglas; Martin, Stefan R.; Thomson, Mark; Regehr, Martin

2015-01-01

Exo-S is a probe-class mission study that includes the Dedicated mission, a 30 millimeters starshade co-launched with a 1.1 millimeter commercial telescope in an Earth-leading deep-space orbit, and the Rendezvous mission, a 34 millimeter starshade intended to work with a 2.4 millimeters telescope in an Earth-Sun L2 orbit. A third design, referred to as the Rendezvous Earth Finder mission, is based on a 40 millimeter starshade and is currently under study. This paper presents error budgets for the detection of Earth-like planets with each of these missions. The budgets include manufacture and deployment tolerances, the allowed thermal fluctuations and dynamic motions, formation flying alignment requirements, surface and edge reflectivity requirements, and the allowed transmission due to micrometeoroid damage.

Heating, moisture, and water budgets of tropical and midlatitude squall lines - Comparisons and sensitivity to longwave radiation

NASA Technical Reports Server (NTRS)

Tao, W.-K.; Simpson, J.; Sui, C.-H.; Ferrier, B.; Lang, S.; Scala, J.; Chou, M.-D.; Pickering, K.

1993-01-01

A 2D time-dependent and nonhydrostatic numerical cloud model is presently used to estimate the heating, moisture, and water budgets in the convective and stratiform regions for both a tropical and a midlatitude squall line. The model encompasses a parameterized, three-class ice phase microphysical scheme and longwave radiative transfer process. It is noted that the convective region plays an important role in the generation of stratiform rainfall for both cases. While a midlevel minimum in the moisture profile for the tropical case is due to vertical eddy transport in the convective region, the contribution to the heating budget by the cloud-scale fluxes is minor; by contrast, the vertical eddy heat-flux is relatively important for the midlatitude case due to the stronger vertical velocities present in the convective cells.

Clouds and the Earth's Radiant Energy System (CERES) algorithm theoretical basis document. Volume 1; Overviews (subsystem 0)

NASA Technical Reports Server (NTRS)

Wielicki, Bruce A. (Principal Investigator); Barkstrom, Bruce R. (Principal Investigator); Baum, Bryan A.; Cess, Robert D.; Charlock, Thomas P.; Coakley, James A.; Green, Richard N.; Lee, Robert B., III; Minnis, Patrick; Smith, G. Louis

1995-01-01

The theoretical bases for the Release 1 algorithms that will be used to process satellite data for investigation of the Clouds and the Earth's Radiant Energy System (CERES) are described. The architecture for software implementation of the methodologies is outlined. Volume 1 provides both summarized and detailed overviews of the CERES Release 1 data analysis system. CERES will produce global top-of-the-atmosphere shortwave and longwave radiative fluxes at the top of the atmosphere, at the surface, and within the atmosphere by using the combination of a large variety of measurements and models. The CERES processing system includes radiance observations from CERES scanning radiometers, cloud properties derived from coincident satellite imaging radiometers, temperature and humidity fields from meteorological analysis models, and high-temporal-resolution geostationary satellite radiances to account for unobserved times. CERES will provide a continuation of the ERBE record and the lowest error climatology of consistent cloud properties and radiation fields. CERES will also substantially improve our knowledge of the Earth's surface radiation budget.

Advancements in Afterbody Radiative Heating Simulations for Earth Entry

NASA Technical Reports Server (NTRS)

Johnston, Christopher O.; Panesi, Marco; Brandis, Aaron M.

2016-01-01

Four advancements to the simulation of backshell radiative heating for Earth entry are presented. The first of these is the development of a flow field model that treats electronic levels of the dominant backshell radiator, N, as individual species. This is shown to allow improvements in the modeling of electron-ion recombination and two-temperature modeling, which are shown to increase backshell radiative heating by 10 to 40%. By computing the electronic state populations of N within the flow field solver, instead of through the quasi-steady state approximation in the radiation code, the coupling of radiative transition rates to the species continuity equations for the levels of N, including the impact of non-local absorption, becomes feasible. Implementation of this additional level of coupling between the flow field and radiation codes represents the second advancement presented in this work, which is shown to increase the backshell radiation by another 10 to 50%. The impact of radiative transition rates due to non-local absorption indicates the importance of accurate radiation transport in the relatively complex flow geometry of the backshell. This motivates the third advancement, which is the development of a ray-tracing radiation transport approach to compute the radiative transition rates and divergence of the radiative flux at every point for coupling to the flow field, therefore allowing the accuracy of the commonly applied tangent-slab approximation to be assessed for radiative source terms. For the sphere considered at lunar-return conditions, the tangent-slab approximation is shown to provide a sufficient level of accuracy for the radiative source terms, even for backshell cases. This is in contrast to the agreement between the two approaches for computing the radiative flux to the surface, which differ by up to 40%. The final advancement presented is the development of a nonequilibrium model for NO radiation, which provides significant backshell

Investigation of Non-Equilibrium Radiation for Earth Entry

NASA Technical Reports Server (NTRS)

Brandis, Aaron; Johnston, Chris; Cruden, Brett

2016-01-01

This paper presents measurements and simulations of non-equilibrium shock layer radiation relevant to high-speed Earth entry data obtained in the NASA Ames Research Center's Electric Arc Shock Tube (EAST) facility. The experiments were aimed at measuring the spatially and spectrally resolved radiance at relevant entry conditions for both an approximate Earth atmosphere (79 N2 : 21 O2) as well as a more accurate composition featuring the trace species Ar and CO2 (78.08 N2 : 20.95 O2 : 0.04 CO2 : 0.93 Ar). The experiments were configured to target a wide range of conditions, of which shots from 8 to 11.5 km/s at 0.2 Torr (26.7 Pa) are examined in this paper. The non-equilibrium component was chosen to be the focus of this study as it can account for a significant percentage of the emitted radiation for Earth entry, and more importantly, non-equilibrium has traditionally been assigned a large uncertainty for vehicle design. The main goals of this study are to present the shock tube data in the form of a non-equilibrium metric, evaluate the level of agreement between the experiment and simulations, identify key discrepancies and to promote discussion about various aspects of modeling non-equilibrium radiating flows. Radiance profiles integrated over discreet wavelength regions, ranging from the VUV through to the NIR, were compared in order to maximize both the spectral coverage and the number of experiments that could be used in the analysis. A previously defined non-equilibrium metric has been used to allow comparisons with several shots and reveal trends in the data. Overall, LAURAHARA is shown to under-predict EAST by as much as 50 and over-predict by as much as 20 depending on the shock speed. DPLRNEQAIR is shown to under-predict EAST by as much as 40 and over-predict by as much as 12 depending on the shock speed. In terms of an upper bound estimate for the absolute error in wall-directed heat flux, at the lower speeds investigated in this paper, 8 to 9 km/s, even

NASA/GEWEX Surface Radiation Budget: Integrated Data Product With Reprocessed Radiance, Cloud, and Meteorology Inputs, and New Surface Albedo Treatment

NASA Technical Reports Server (NTRS)

Cox, Stephen J.; Stackhouse, Paul W., Jr.; Gupta, Shashi K.; Mikovitz, J. Colleen; Zhang, Taiping

2016-01-01

The NASA/GEWEX Surface Radiation Budget (SRB) project produces shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. Spatial resolution is 1 degree. The current release 3.0 (available at gewex-srb.larc.nasa.gov) uses the International Satellite Cloud Climatology Project (ISCCP) DX product for pixel level radiance and cloud information. This product is subsampled to 30 km. ISCCP is currently recalibrating and recomputing their entire data series, to be released as the H product, at 10km resolution. The ninefold increase in pixel number will allow SRB a higher resolution gridded product (e.g. 0.5 degree), as well as the production of pixel-level fluxes. In addition to the input data improvements, several important algorithm improvements have been made. Most notable has been the adaptation of Angular Distribution Models (ADMs) from CERES to improve the initial calculation of shortwave TOA fluxes, from which the surface flux calculations follow. Other key input improvements include a detailed aerosol history using the Max Planck Institut Aerosol Climatology (MAC), temperature and moisture profiles from HIRS, and new topography, surface type, and snow/ice. Here we present results for the improved GEWEX Shortwave and Longwave algorithm (GSW and GLW) with new ISCCP data, the various other improved input data sets and the incorporation of many additional internal SRB model improvements. As of the time of abstract submission, results from 2007 have been produced with ISCCP H availability the limiting factor. More SRB data will be produced as ISCCP reprocessing continues. The SRB data produced will be released as part of the Release 4.0 Integrated Product, recognizing the interdependence of the radiative fluxes with other GEWEX products providing estimates of the Earth's global water and energy cycle (I.e., ISCCP, SeaFlux, LandFlux, NVAP, etc.).

Making NASA Earth Observing System Satellite Data Accessible to the K-12 and Citizen Scientist Communities

NASA Technical Reports Server (NTRS)

Moore, Susan W.; Phelps, Carrie S.; Chambers, Lin H.

2004-01-01

The Atmospheric Sciences Data Center (ASDC) at NASA s Langley Research Center houses over 700 data sets related to Earth s radiation budget, clouds, aerosols and tropospheric chemistry. These data sets are produced to increase academic understanding of the natural and anthropogenic perturbations that influence global climate change. The Mentoring and inquirY using NASA Data on Atmospheric and earth science for Teachers and Amateurs (MY NASA DATA) project has been established to systematically support educational activities at all levels of formal and informal education by reducing these large data holdings to microsets that will be easily explored and understood by the K-12 and the amateur scientist communities

Absolute Radiation Measurements in Earth and Mars Entry Conditions

NASA Technical Reports Server (NTRS)

Cruden, Brett A.

2014-01-01

This paper reports on the measurement of radiative heating for shock heated flows which simulate conditions for Mars and Earth entries. Radiation measurements are made in NASA Ames' Electric Arc Shock Tube at velocities from 3-15 km/s in mixtures of N2/O2 and CO2/N2/Ar. The technique and limitations of the measurement are summarized in some detail. The absolute measurements will be discussed in regards to spectral features, radiative magnitude and spatiotemporal trends. Via analysis of spectra it is possible to extract properties such as electron density, and rotational, vibrational and electronic temperatures. Relaxation behind the shock is analyzed to determine how these properties relax to equilibrium and are used to validate and refine kinetic models. It is found that, for some conditions, some of these values diverge from non-equilibrium indicating a lack of similarity between the shock tube and free flight conditions. Possible reasons for this are discussed.

Evaluating cloudiness in an AGCM with Cloud Vertical Structure classes and their radiative effects

NASA Astrophysics Data System (ADS)

Lee, D.; Cho, N.; Oreopoulos, L.; Barahona, D.

2017-12-01

Clouds are recognized not only as the main modulator of Earth's Radiation Budget but also as the atmospheric constituent carrying the largest uncertainty in future climate projections. The presentation will showcase a new framework for evaluating clouds and their radiative effects in Atmospheric Global Climate Models (AGCMs) using Cloud Vertical Structure (CVS) classes. We take advantage of a new CVS reference dataset recently created from CloudSat's 2B-CLDCLASS-LIDAR product and which assigns observed cloud vertical configurations to nine simplified CVS classes based on cloud co-occurrence in three standard atmospheric layers. These CVS classes can also be emulated in GEOS-5 using the subcolumn cloud generator currently paired with the RRTMG radiation package as an implementation of the McICA scheme. Comparisons between the observed and modeled climatologies of the frequency of occurrence of the various CVS classes provide a new vantage point for assessing the realism of GEOS-5 clouds. Furthermore, a comparison between observed and modeled cloud radiative effects according to their CVS is also possible thanks to the availability of CloudSat's 2B-FLXHR-LIDAR product and our ability to composite radiative fluxes by CVS class - both in the observed and modeled realm. This latter effort enables an investigation of whether the contribution of the various CVS classes to the Earth's radiation budget is represented realistically in GEOS-5. Making this new pathway of cloud evaluation available to the community is a major step towards the improved representation of clouds in climate models.

A new radiation infrastructure for the Modular Earth Submodel System (MESSy, based on version 2.51)

NASA Astrophysics Data System (ADS)

Dietmüller, Simone; Jöckel, Patrick; Tost, Holger; Kunze, Markus; Gellhorn, Catrin; Brinkop, Sabine; Frömming, Christine; Ponater, Michael; Steil, Benedikt; Lauer, Axel; Hendricks, Johannes

2016-06-01

The Modular Earth Submodel System (MESSy) provides an interface to couple submodels to a base model via a highly flexible data management facility (Jöckel et al., 2010). In the present paper we present the four new radiation related submodels RAD, AEROPT, CLOUDOPT, and ORBIT. The submodel RAD (including the shortwave radiation scheme RAD_FUBRAD) simulates the radiative transfer, the submodel AEROPT calculates the aerosol optical properties, the submodel CLOUDOPT calculates the cloud optical properties, and the submodel ORBIT is responsible for Earth orbit calculations. These submodels are coupled via the standard MESSy infrastructure and are largely based on the original radiation scheme of the general circulation model ECHAM5, however, expanded with additional features. These features comprise, among others, user-friendly and flexibly controllable (by namelists) online radiative forcing calculations by multiple diagnostic calls of the radiation routines. With this, it is now possible to calculate radiative forcing (instantaneous as well as stratosphere adjusted) of various greenhouse gases simultaneously in only one simulation, as well as the radiative forcing of cloud perturbations. Examples of online radiative forcing calculations in the ECHAM/MESSy Atmospheric Chemistry (EMAC) model are presented.

Skylab S191, S192 program descriptions. [earth radiation data analysis

NASA Technical Reports Server (NTRS)

Mack, M.

1976-01-01

Software developed to assist in assessing and analyzing earth radiation data obtained from Skylab S191 and S192 experiments are described. A block data generation routine is included along with a plot program for the S191 experiment. Changes in format from that of the original JSC tapes are discussed.

Impacts of Advection Fog on the Surface Radiation Budget in coastal California

NASA Astrophysics Data System (ADS)

Oliphant, A. J.; Baguskas, S. A.

2016-12-01

Clouds and other aerosols alter the nature of the surface radiation budget (SRB) by reducing the quantity and changing the quality of solar radiation incident upon the surface as well as enhancing down-welling thermal infrared radiation (TIR) and suppressing upwelling TIR during daytime. Our study aimed to characterize the impact of advection fog on SRB components in coastal California, and develop methods to identify and characterize fog events using surface-mounted radiometers. First, we generated a climatology of summertime SRB components based on observations from south-western San Francisco, CA (2005-2008). From this we drew clear distinctions in characteristic surface radiation regimes between foggy and clear-sky days using atmospheric transmission indices during the day and down-welling TIR at any time of day. Secondly, we applied these empirical models to a dataset gathered in 2016 on a coastal strawberry farm located in the fog-belt in the Salinas Valley, California. From this we investigated methods to improve the models to distinguish fog events that cause surface deposition from those when the stratocumulus deck is slightly elevated, i.e., overcast conditions. On average, coastal fog was found to decrease incident solar radiation by about 50% and increase the diffuse fraction by 81%. There was a mean difference of about 70 W m-2 in down-welling TIR between clear-sky and foggy conditions throughout the diurnal cycle, with a standard deviation of less than 10 W m-2, which allows robust 24-hr estimates of fog presence using simple thresholds. As the cloud base lowers in elevation during fog events, the differences in temperature between the cloud base and surface is reduced; therefore, the ratio of opposing TIR fluxes is related to cloud base heights and should help disentangle `fog' events to better inform environmental drivers of coastal ecosystems.

Clinton Administration announces FY 2001 budget request

NASA Astrophysics Data System (ADS)

Showstack, Randy

Blessed with a strong US. economy the Clinton Administration on February 7 released a fiscal year 2001 federal budget request totaling a whopping $1,835 billion. Most of the funding request is slated for big ticket items including Social Security defense spending, Medicaid, Medicare, and paying down the federal debt. However, within the 19% of the budget that funds non-defense discretionary programs,science agencies receive fairly healthy increases.The National Science Foundation (NSF) budget request would increase NSF funding by 17.3% $675 million and bring the total budget request to $4.6 billion. This includes significant increases for several initiatives: biocomplexity in the environment, information technology research, nanoscale science and engineering, and 21st century workforce. Among the major Earth science projects are launching the Earthscope initiative which includes the US Array and San Andreas Fault Observatory at Depth (SAFOD) and the National Ecological Observatory Network (NEON).

The utility of the historical record in assessing future carbon budgets

NASA Astrophysics Data System (ADS)

Millar, R.; Friedlingstein, P.; Allen, M. R.

2017-12-01

It has long been known that the cumulative emissions of carbon dioxide (CO2) is the most physically relevant determiner of long-lived anthropogenic climate change, with an approximately linear relationship between CO2-induced global mean surface warming and cumulative emissions. The historical observational record offers a way to constrain the relationship between cumulative carbon dioxide emission and global mean warming using observations to date. Here we show that simple regression analysis indicates that the 1.5°C carbon budget would be exhausted after nearly three decades of current emissions, substantially in excess of many estimates from Earth System Models. However, there are many reasons to be cautious about carbon budget assessments from the historical record alone. Accounting for the uncertainty in non-CO2 radiative forcing using a simple climate model and a standard optimal fingerprinting detection attribution technique gives substantial uncertainty in the contribution of CO2 warming to date, and hence the transient climate response to cumulative emissions. Additionally, the existing balance between CO2 and non-CO2 forcing may change in the future under ambitious mitigation scenarios as non-CO2 emissions become more (or less) important to global mean temperature changes. Natural unforced variability can also have a substantial impact on estimates of remaining carbon budgets. By examining all warmings of a given magnitude in both the historical record and past and future ESM simulations we quantify the impact unforced climate variability may have on estimates of remaining carbon budgets, derived as a function of estimated non-CO2 warming and future emission scenario. In summary, whilst the historical record can act as a useful test of climate models, uncertainties in the response to future cumulative emissions remain large and extrapolations of future carbon budgets from the historical record alone should be treated with caution.

The Geomagnetic Field and Radiation in Near-Earth Orbits

NASA Technical Reports Server (NTRS)

Heirtzler, J. R.

1999-01-01

This report shows, in detail, how the geomagnetic field interacts with the particle flux of the radiation belts to create a hazard to spacecraft and humans in near-Earth orbit. It illustrates the geometry of the geomagnetic field lines, especially around the area where the field strength is anomalously low in the South Atlantic Ocean. It discusses how the field will probably change in the future and the consequences that may have on hazards in near space.

A Wire Antenna Designed for Space Wave Radiation Over the Earth Using a Genetic Algorithm

DTIC Science & Technology

1997-12-01

are extended beyond that of connecting the wires in series. 1.6 Assumptions 1.6.1 Smooth Earth. It was not prudent for the research to account for an...and circuit grounds are connected in some manner. 1.7 Scope The research proposes a system antenna design, taking into account the link budget. The...1.10 Goals The purpose of the research is to conduct a thorough design approach taking into account all aspects of antenna design, to include the

A carbon dioxide radiance model of the earth planet using the conical earth sensor data

NASA Astrophysics Data System (ADS)

Deng, Loulou; Mei, Zhiwu; Tu, Zhijun; Yuan, Jun; He, Ting; Wei, Yi

2013-10-01

Climate Modeling results show that about 50% of the Earth's outgoing radiation and 75% of the atmospheric outgoing radiation are contained in the far infrared. Generally the earth is considered as a 220~230 K blackbody, and the peak breadth of the Earth's outgoing radiation is around the wavelength of 10 micron. The atmospheric outgoing radiation are contained with five spectral intervals: the water vapor band from 6.33 to 6.85 microns, the ozone band from 8.9 to 10.1microns, the atmospheric window from 10.75 to 11.75 microns, the carbon dioxide band from 14 to 16 microns, and finally the rotational water vapor band from 21 to 125 microns. The properties of the carbon dioxide band is stable than other bands which has been chosen for the work Spectrum of the earth sensors. But the radiation energy of carbon dioxide band is variety and it is a function of latitude, season and weather conditions. Usually the luminance of the Earth's radiation (14 to 16 μm) is from 3 to 7 W/m2Sr. Earth sensor is an important instrument of the Attitude and Orbit Control System (AOCS), and it is sensitive to the curve of the earth's and atmospheric outgoing radiation profile to determine the roll and pitch angles of satellite which are relative to nadir vector. Most earth sensors use profile data gathered form Project Scanner taken in August and December 1966. The earth sensor referred in this paper is the conical scanning earth sensor which is mainly used in the LEO (Low Earth Orbit) satellite. A method to determine the luminance of earth's and atmospheric outgoing radiation (carbon dioxide) using the earth sensor is discussed in this paper. When the conical scanning sensor scan form the space to the earth, a pulse is produced and the pulse breadth is scale with the infrared radiation luminance. Then the infrared radiation luminance can be calculated. A carbon dioxide radiance model of the earth's and atmospheric outgoing radiation is obtained according the luminance data about with

Prompt enhancement of the Earth's outer radiation belt due to substorm electron injections

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

Tang, C. L.; Zhang, J. -C.; Reeves, G. D.

Here, we present multipoint simultaneous observations of the near-Earth magnetotail and outer radiation belt during the substorm electron injection event on 16 August 2013. Time History of Events and Macroscale Interactions during Substorms A in the near-Earth magnetotail observed flux-enhanced electrons of 300 keV during the magnetic field dipolarization. Geosynchronous orbit satellites also observed the intensive electron injections. Located in the outer radiation belt, RBSP-A observed enhancements of MeV electrons accompanied by substorm dipolarization. The phase space density (PSD) of MeV electrons at L* ~5.4 increased by 1 order of magnitude in 1 h, resulting in a local PSD peakmore » of MeV electrons, which was caused by the direct effect of substorm injections. We also detected an enhanced MeV electrons in the heart of the outer radiation belt within 2 h, which may be associated with intensive substorm electron injections and subsequent local acceleration by chorus waves. Multipoint observations have shown that substorm electron injections not only can be the external source of MeV electrons at the outer edge of the outer radiation belt (L* ~5.4) but also can provide the intensive seed populations in the outer radiation belt. These initial higher-energy electrons from injection can reach relativistic energy much faster. Furthermore, these observations also provide evidence that enhanced substorm electron injections can explain rapid enhancements of MeV electrons in the outer radiation belt.« less

Prompt enhancement of the Earth's outer radiation belt due to substorm electron injections

DOE PAGES

Tang, C. L.; Zhang, J. -C.; Reeves, G. D.; ...

2016-12-17

Here, we present multipoint simultaneous observations of the near-Earth magnetotail and outer radiation belt during the substorm electron injection event on 16 August 2013. Time History of Events and Macroscale Interactions during Substorms A in the near-Earth magnetotail observed flux-enhanced electrons of 300 keV during the magnetic field dipolarization. Geosynchronous orbit satellites also observed the intensive electron injections. Located in the outer radiation belt, RBSP-A observed enhancements of MeV electrons accompanied by substorm dipolarization. The phase space density (PSD) of MeV electrons at L* ~5.4 increased by 1 order of magnitude in 1 h, resulting in a local PSD peakmore » of MeV electrons, which was caused by the direct effect of substorm injections. We also detected an enhanced MeV electrons in the heart of the outer radiation belt within 2 h, which may be associated with intensive substorm electron injections and subsequent local acceleration by chorus waves. Multipoint observations have shown that substorm electron injections not only can be the external source of MeV electrons at the outer edge of the outer radiation belt (L* ~5.4) but also can provide the intensive seed populations in the outer radiation belt. These initial higher-energy electrons from injection can reach relativistic energy much faster. Furthermore, these observations also provide evidence that enhanced substorm electron injections can explain rapid enhancements of MeV electrons in the outer radiation belt.« less

Wave energy budget analysis in the Earth’s radiation belts uncovers a missing energy

PubMed Central

Artemyev, A.V.; Agapitov, O.V.; Mourenas, D.; Krasnoselskikh, V.V.; Mozer, F.S.

2015-01-01

Whistler-mode emissions are important electromagnetic waves pervasive in the Earth’s magnetosphere, where they continuously remove or energize electrons trapped by the geomagnetic field, controlling radiation hazards to satellites and astronauts and the upper-atmosphere ionization or chemical composition. Here, we report an analysis of 10-year Cluster data, statistically evaluating the full wave energy budget in the Earth’s magnetosphere, revealing that a significant fraction of the energy corresponds to hitherto generally neglected very oblique waves. Such waves, with 10 times smaller magnetic power than parallel waves, typically have similar total energy. Moreover, they carry up to 80% of the wave energy involved in wave–particle resonant interactions. It implies that electron heating and precipitation into the atmosphere may have been significantly under/over-valued in past studies considering only conventional quasi-parallel waves. Very oblique waves may turn out to be a crucial agent of energy redistribution in the Earth’s radiation belts, controlled by solar activity. PMID:25975615

SOLAR COSMIC RAYS AND SOFT RADIATION OBSERVED AT 5,000,000 KILOMETERS FROM EARTH

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

Arnoldy, R.L.; Hoffman, R.A.; Winckler, J.R.

1960-09-01

During the period Mar. 27 to Apr. 6, 1960, the integrating ionization chamber and Geiger counter in Pioneer V detected solar cosmic rays and some soft- radiation effects associated with a high level of solar activity. The space probe was 5 x 10/sup 6/ km from the earth, approximately in the plane of the ecliptic, and located somewhat behind the sunearth radius toward the sun. The solar activity was associated with McMath plage region 5615 and was characterized by numerous flares of all sizes, large loops and surge prominences, and strong emission over a wide range of frequencies. On Mar.more » 31 at 0800 UT, a severe geomagnetic storm began on earth accompanied by major earth-current disturbances, a complete blackout of the North Atlantic communications channel, and auroral displays. At the same time, a large Forbush decrease occurred in the galactic cosmic radiation. An intense series of balloon flights was conducted to record the counting-rate increases at high altitudes due to solar cosmic rays and auroral x rays. Explorer VII showed substantial changes in the radiation belts and detected the solar cosmic rays. The observations of Pioneer V are summarized and compared to the findings of Explorer VII for the same period. (B.O.G.)« less

Solar irradiance changes and photobiological effects at earth's surface following astrophysical ionizing radiation events.

PubMed

Thomas, Brian C; Neale, Patrick J; Snyder, Brock R

2015-03-01

Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth, primarily through depletion of stratospheric ozone and subsequent increase in surface-level solar ultraviolet radiation. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In this work, we employed the Tropospheric Ultraviolet and Visible (TUV) radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light) for clear-sky conditions and fixed aerosol parameter values. We also considered a wide range of biological effects on organisms ranging from humans to phytoplankton. We found that past work overestimated UVB irradiance but that relative estimates for increase in exposure to DNA-damaging radiation are still similar to our improved calculations. We also found that the intensity of biologically damaging radiation varies widely with organism and specific impact considered; these results have implications for biosphere-level damage following astrophysical ionizing radiation events. When considering changes in surface-level visible light irradiance, we found that, contrary to previous assumptions, a decrease in irradiance is only present for a short time in very limited geographical areas; instead we found a net increase for most of the modeled time-space region. This result has implications for proposed climate changes associated with ionizing radiation events.

Thermal evolution of the earth

NASA Technical Reports Server (NTRS)

Spohn, T.

1984-01-01

The earth's heat budget and models of the earth's thermal evolution are discussed. Sources of the planetary heat are considered and modes of heat transport are addressed, including conduction, convection, and chemical convection. Thermal and convectional models of the earth are covered, and models of thermal evolution are discussed in detail, including changes in the core, the influence of layered mantle convection on the thermal evolution, and the effect of chemical differentiation on the continents.

Absorption of Solar Radiation by Clouds: An Overview

NASA Technical Reports Server (NTRS)

Tsay, Si-Chee; Einaudi, Franco (Technical Monitor)

2000-01-01

This talk provides an overview of the subject of absorption of solar radiation by clouds in the earth's atmosphere. The paper summarizes the available evidence which points to disagreements between theoretical and observed values of cloud absorption (and reflections). The importance of these discrepancies, particularly to remote sensing of clouds as well as to studies of cloud physics and earth radiation budgets, is emphasized. Existing cloud absorption and reflection measurements are reviewed and the persistent differences that exist between calculated and measured near-infrared cloud albedos are highlighted. Various explanations for these reflection and absorption discrepancies are discussed under two separate paths: a theoretician's approach and an experimentalist's approach. Examples for the former approach include model accuracy tests, large-droplet hypothesis, excess absorbing aerosol, enhanced water vapor continuum absorption, and effects of cloud inhomogeneity. The latter approach focuses on discussions of instrumental device, calibration, operational strategy, and signal/noise separation. A recommendation for future activities on this subject will be given.

Balancing the books - a statistical theory of prospective budgets in Earth System science

NASA Astrophysics Data System (ADS)

O'Kane, J. Philip

An honest declaration of the error in a mass, momentum or energy balance, ɛ, simply raises the question of its acceptability: "At what value of ɛ is the attempted balance to be rejected?" Answering this question requires a reference quantity against which to compare ɛ. This quantity must be a mathematical function of all the data used in making the balance. To deliver this function, a theory grounded in a workable definition of acceptability is essential. A distinction must be drawn between a retrospective balance and a prospective budget in relation to any natural space-filling body. Balances look to the past; budgets look to the future. The theory is built on the application of classical sampling theory to the measurement and closure of a prospective budget. It satisfies R.A. Fisher's "vital requirement that the actual and physical conduct of experiments should govern the statistical procedure of their interpretation". It provides a test, which rejects, or fails to reject, the hypothesis that the closing error on the budget, when realised, was due to sampling error only. By increasing the number of measurements, the discrimination of the test can be improved, controlling both the precision and accuracy of the budget and its components. The cost-effective design of such measurement campaigns is discussed briefly. This analysis may also show when campaigns to close a budget on a particular space-filling body are not worth the effort for either scientific or economic reasons. Other approaches, such as those based on stochastic processes, lack this finality, because they fail to distinguish between different types of error in the mismatch between a set of realisations of the process and the measured data.

Solar UV Radiation and the Origin of Life On Earth

NASA Technical Reports Server (NTRS)

Heap, S. R.; Lanz, T.; Hubeny, I.; Gaidos, E.; Oegerle, William R. (Technical Monitor)

2002-01-01

We have embarked on a program aimed at understanding the atmosphere of the early Earth, because of its importance as a greenhouse, radiation shield and energy source for life. Here, we give a progress report on the first phase of this program to establish the UV radiation from the early Sun. We have obtained ultraviolet spectra (STIS, FUSE, EUVE) of carefully selected nearby, young solar-type stars, which act as surrogates for the early Sun We are making detailed non-LTE analyses of the spectra and constructing models of their photospheres + chromospheres. Once validated, these models will allow us to extrapolate our theoretical spectra to other metallicities and to unobserved spectral regions.

How well do we understand the Earth's radiation budget and the role of clouds? Selected results of the GEWEX radiation flux assessment

NASA Astrophysics Data System (ADS)

Raschke, E.; Kinne, S.

2013-05-01

Multi-year average radiative flux maps of three satellite data-sets (CERES, ISSCP and GEWEX-SRB) are compared to each other and to typical values by global modeling (median values of results of 20 climate models of the 4th IPCC Assessment). Diversity assessments address radiative flux products and at the top of the atmosphere (TOA) and the surface, with particular attention to impacts by clouds. Involving both data from surface and TOA special attention is given to the vertical radiation flux divergence and on the infrared Greenhouse effect, which are rarely shown in literature.

Long-term Radiation Budget Variability in the Northern Eurasian Region: Assessing the Interaction with Fire

NASA Astrophysics Data System (ADS)

Stackhouse, P. W.; Soja, A. J.; Zhang, T.; Mikovitz, J. C.

2013-12-01

In terms of global change, boreal regions are particularly important, because significant warming and change are already evident and significant future warming is predicted. Mean global air temperature has increased by 0.74°C in the last century, and temperatures are predicted to increase by 1.8°C to 4°C by 2090, depending on the Inter-governmental Panel on Climate Change (IPCC) scenario. Some of the greatest temperature increases are currently found in the Northern Eurasian winter and spring, which has led to longer growing seasons, increased potential evapotranspiration and extreme fire weather [Groisman et al., 2007]. In the Siberian Sayan, winter temperatures have already exceeded a 2090 Hadley Centre scenario (HadCM3GGa1) [Soja et al., 2007]. There is evidence of climate-induced change across the circumboreal in terms of increased infestations, alterations in vegetation and increased fire regimes (area burned, fire frequency, severity and number of extreme fire seasons). In this paper, we analyzed long-term surface radiation data sets from the NASA/GEWEX (Global Energy and Water Exchanges) Surface Radiation Budget data products, CERES Surface EBAF and SYN data products and also the available surface radiation measurements in the region. First, we show that during overlap years SRB and CERES data products agree very well in terms of anomalies and we'll use this fact to evaluate 30 years of satellite based estimates of the variability of downwelling SW parameters first corresponding to locations of surface measurements and then for the region as a whole. We also show the observed variability of other SW components such as the net SW and the albedo. Next we assess the variability of the downward and LW fluxes over time and compare these to variability observed in the surface temperature and other meteorological measurements. We assess anomalies on various spatial scales. Finally, we assess the correlation of this variability in specific locations to known fire

Annual Cycle of Surface Longwave Radiation

NASA Technical Reports Server (NTRS)

Mlynczak, Pamela E.; Smith, G. Louis; Wilber, Anne C.; Stackhouse, Paul W.

2011-01-01

The annual cycles of upward and downward longwave fluxes at the Earth s surface are investigated by use of the NASA/GEWEX Surface Radiation Budget Data Set. Because of the immense difference between the heat capacity of land and ocean, the surface of Earth is partitioned into these two categories. Principal component analysis is used to quantify the annual cycles. Over land, the first principal component describes over 95% of the variance of the annual cycle of the upward and downward longwave fluxes. Over ocean the first term describes more than 87% of these annual cycles. Empirical orthogonal functions show the corresponding geographical distributions of these cycles. Phase plane diagrams of the annual cycles of upward longwave fluxes as a function of net shortwave flux show the thermal inertia of land and ocean.

Angular momentum budget of the radiational S1 ocean tide

NASA Astrophysics Data System (ADS)

Schindelegger, Michael; Dobslaw, Henryk; Poropat, Lea; Salstein, David; Böhm, Johannes

2016-04-01

The balance of diurnal S1 oceanic angular momentum (OAM) variations through torques at the sea surface and the bottom topography is validated using both a barotropic and a baroclinic numerical tide model. This analysis discloses the extent to which atmosphere-driven S1 forward simulations are reliable for use in studies of high-frequency polar motion and changes in length-of-day. Viscous and dissipative torques associated with wind stress, bottom friction, as well as internal tidal energy conversion are shown to be small, and they are overshadowed by gravitational and pressure-related interaction forces. In particular, the zonal OAM variability of S1 is almost completely balanced by the water pressure torque on the local bathymetry, whereas in the prograde equatorial case also the air pressure torque on the seafloor as well as ellipsoidal contributions from the non-spherical atmosphere and solid Earth must be taken into account. Overall, the OAM budget is well closed in both the axial and the equatorial directions, thus allowing for an identification of the main diurnal angular momentum sinks in the ocean. The physical interaction forces are found to be largest at shelf breaks and continental slopes in low latitudes, with the most dominant contribution coming from the Indonesian archipelago.

Extrapolation of earth-based solar irradiance measurements to exoatmospheric levels for broad-band and selected absorption-band observations

NASA Technical Reports Server (NTRS)

Reagan, John A.; Pilewskie, Peter A.; Scott-Fleming, Ian C.; Herman, Benjamin M.; Ben-David, Avishai

1987-01-01

Techniques for extrapolating earth-based spectral band measurements of directly transmitted solar irradiance to equivalent exoatmospheric signal levels were used to aid in determining system gain settings of the Halogen Occultation Experiment (HALOE) sunsensor being developed for the NASA Upper Atmosphere Research Satellite and for the Stratospheric Aerosol and Gas (SAGE) 2 instrument on the Earth Radiation Budget Satellite. A band transmittance approach was employed for the HALOE sunsensor which has a broad-band channel determined by the spectral responsivity of a silicon detector. A modified Langley plot approach, assuming a square-root law behavior for the water vapor transmittance, was used for the SAGE-2 940 nm water vapor channel.

Towards quantifying global aerosol radiative effects using lidar

NASA Astrophysics Data System (ADS)

Thorsen, T. J.

2017-12-01

Spaceborne lidar observations alleviate many of the limitations of passivesensors and have great potential to provide accurate global all-sky estimatesof the aerosol direct radiative effect (DRE). However, analysis of CALIPSOlidar observations show that CALIPSO does not detect allradiatively-significant aerosol, i.e. aerosol that directly modifies theEarth's radiation budget. We estimated that using CALIPSO observationsresults in an underestimate of the magnitude of the global mean aerosol DREby up to 54%. The CATS lidar on-board the ISS is shown to have a poorersensitivity than CALIPSO and the expected sensitivity of the upcoming ATLIDlidar on EarthCARE indicates that calculations of the aerosol DRE willcontinue to be significantly biased. Improvements to our knowledge of aerosol forcing, which contributes thelargest uncertainty to climate sensitivity, could be achieved by a futurespace-based HSRL mission. To this end, high-accuracy ground-based andairborne lidar datasets have been used to compute the detection sensitivityrequired to accurately resolve the aerosol DRE. Multiwavelength HSRLmeasurements also can retrieve vertically-resolved aerosol optical propertiesneeded for radiative transfer calculations which are not provided by currentsatellite observations. Current satellite observations also do not provideall the quantities needed to compute the aerosol direct radiative forcing,i.e. the radiative effect of just anthropogenic aerosols. A multiwavelengthHSRL allows for a more refined aerosol classification to be made enablingboth calculations of anthropogenic aerosol radiative effects and betterconstraints on global models.

Earth radiation balance as observed and represented in CMIP5 models

NASA Astrophysics Data System (ADS)

Wild, Martin; Folini, Doris; Schär, Christoph; Loeb, Norman; König-Langlo, Gert

2014-05-01

The genesis and evolution of Earth's climate is largely regulated by the Earth radiation balance. Despite of its key role in the context of climate change, substantial uncertainties still exist in the quantification of the magnitudes of its different components, and its representation in climate models. While the net radiative energy flows in and out of the climate system at the top of atmosphere are now known with considerable accuracy from new satellite programs such as CERES and SORCE, the energy distribution within the climate system and at the Earth's surface is less well determined. Accordingly, the magnitudes of the components of the surface energy balance have recently been controversially disputed, and potential inconsistencies between the estimated magnitudes of the global energy and water cycle have been emphasized. Here we summarize this discussion as presented in Chapter 2.3 of the 5th IPCC assessment report (AR5). In this context we made an attempt to better constrain the magnitudes of the surface radiative components with largest uncertainties. In addition to satellite observations, we thereby made extensive use of the growing number of surface observations to constrain the radiation balance not only from space, but also from the surface. We combined these observations with the latest modeling efforts performed for AR5 (CMIP5) to infer best estimates for the global mean surface radiative components. Our analyses favor global mean values of downward surface solar and thermal radiation near 185 and 342 Wm-2, respectively, which are most compatible with surface observations (Wild et al. 2013). These estimates are on the order of 10 Wm-2 lower and higher, respectively, than in some of the previous global energy balance assessments, including those presented in previous IPCC reports. It is encouraging that these estimates, which make full use of the information contained in the surface networks, coincide within 2 Wm-2 with the latest satellite

Quantitative Assessment of the Integrated Response in Global Heat and Moisture Budgets to Changing Solar Irradiance

NASA Technical Reports Server (NTRS)

White, Warren B.; Cayan, Daniel R.; Dettinger, Michael; Sharber, James (Technical Monitor)

2001-01-01

Earlier, we found time sequences of basin- and global-average upper ocean temperature (that is, diabatic heat storage above the main pycnocline) for 40 years from 1955-1994 and of sea surface temperature for 95 years from 1900-1994 associated with changes in the Sun's radiative forcing on decadal and interdecadal timescales, lagging by 10 deg.- 30 deg. of phase and confined to the upper 60-120 m. Yet, the observed changes in upper ocean temperature (approx. 0.1 K) were approximately twice those expected from the Stefan-Boltzmann black-body radiation law for the Earth's surface, with phase lags (0 deg. to 30 deg. of phase) much shorter than the 90 deg. phase shift expected as well. Moreover, White et al. (1997, 1998) found the Earth's global decadal mode in covarying SST and SLP anomalies phase locked to the decadal signal in the Sun's irradiance. Yet, Allan (2000) found this decadal signal also characterized by patterns similar to those observed on biennial and interannual time scales; that is, the Troposphere Biennial Oscillation (TBO) and the El Nino and the Southern Oscillation (ENSO). This suggested that small changes in the Sun's total irradiance could excite this global decadal mode in the Earth's ocean-atmosphere-terrestrial system similar to those excited internally on biennial and interannual period scales. This is a significant finding, proving that energy budget models (that is, models based on globally-averaged radiation balances) yield unrealistic responses. Thus, the true response must include positive and negative feedbacks in the Earth's ocean-atmosphere-terrestrial system as its internal mode (that is, the natural mode of the system) respond in damped resonance to quasi-periodic decadal changes in the Sun's irradiance. Moreover, these responses are not much different from those occurring internally on biennial and interannual period scales.

The Earth's radiation belts modelling : main issues and key directions for improvement

NASA Astrophysics Data System (ADS)

Maget, Vincent; Boscher, Daniel

The Earth's radiation belts can be considered as an opened system covering a wide part of the inner magnetosphere which closely interacts with the surrounding cold plasma. Although its population constitutes only the highly energetic tail of the global inner magnetosphere plasma (electrons from a few tens of keV to more than 5 MeV and protons up to 500MeV), their modelling is of prime importance for satellite robustness design. They have been modelled at ONERA for more than 15 years now through the Salammbˆ code, which models the dynamic of the Earth's radiation belts at the drift timescale (order of the hour). It takes into accounts the main processes acting on the trapped particles, which depends on the electromagnetic configuration and on the characteristics of the surrounding cold plasma : the ionosphere as losses terms, the plasmasheet as sources ones and the plasmasphere through interactions (waves-particles interactions, coulomb scattering, electric fields shielding, . . . ). Consequently, a fine knowledge of these environments and their interactions with the radiation belts is of prime importance in their modelling. Issues in the modelling currently exist, but key directions for improvements can also be highlighted. This talk aims at presenting both of them according to recent developments performed at ONERA besides the Salammbˆ code. o

Modeling the effectiveness of shielding in the earth-moon-mars radiation environment using PREDICCS: five solar events in 2012

NASA Astrophysics Data System (ADS)

Quinn, Philip R.; Schwadron, Nathan A.; Townsend, Larry W.; Wimmer-Schweingruber, Robert F.; Case, Anthony W.; Spence, Harlan E.; Wilson, Jody K.; Joyce, Colin J.

2017-08-01

Radiation in the form of solar energetic particles (SEPs) presents a severe risk to the short-term health of astronauts and the success of human exploration missions beyond Earth's protective shielding. Modeling how shielding mitigates the dose accumulated by astronauts is an essential step toward reducing these risks. PREDICCS (Predictions of radiation from REleASE, EMMREM, and Data Incorporating the CRaTER, COSTEP, and other SEP measurements) is an online tool for the near real-time prediction of radiation exposure at Earth, the Moon, and Mars behind various levels of shielding. We compare shielded dose rates from PREDICCS with dose rates from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard the Lunar Reconnaissance Orbiter (LRO) at the Moon and from the Radiation Assessment Detector (RAD) on the Mars Science Laboratory (MSL) during its cruise phase to Mars for five solar events in 2012 when Earth, MSL, and Mars were magnetically well connected. Calculations of the accumulated dose demonstrate a reasonable agreement between PREDICCS and RAD ranging from as little as 2% difference to 54%. We determine mathematical relationships between shielding levels and accumulated dose. Lastly, the gradient of accumulated dose between Earth and Mars shows that for the largest of the five solar events, lunar missions require aluminum shielding between 1.0 g cm-2 and 5.0 g cm-2 to prevent radiation exposure from exceeding the 30-day limits for lens and skin. The limits were not exceeded near Mars.

Dynamics of Quasi-Electrostatic Whistler waves in Earth's Radiation belts

NASA Astrophysics Data System (ADS)

Goyal, R.; Sharma, R. P.; Gupta, D. N.

2017-12-01

A numerical model is proposed to study the dynamics of high amplitude quasi-electrostatic whistler waves propagating near resonance cone angle and their interaction with finite frequency kinetic Alfvén waves (KAWs) in Earth's radiation belts. The quasi-electrostatic character of whistlers is narrated by dynamics of wave propagating near resonance cone. A high amplitude whistler wave packet is obtained using the present analysis which has also been observed by S/WAVES instrument onboard STEREO. The numerical simulation technique employed to study the dynamics, leads to localization (channelling) of waves as well as turbulent spectrum suggesting the transfer of wave energy over a range of frequencies. The turbulent spectrum also indicates the presence of quasi-electrostatic whistlers and density fluctuations associated with KAW in radiation belts plasma. The ponderomotive force of pump quasi-electrostatic whistlers (high frequency) is used to excite relatively much lower frequency waves (KAWs). The wave localization and steeper spectra could be responsible for particle energization or heating in radiation belts.

Atmospheric water budget over the South Asian summer monsoon region

NASA Astrophysics Data System (ADS)

Unnikrishnan, C. K.; Rajeevan, M.

2018-04-01

High resolution hybrid atmospheric water budget over the South Asian monsoon region is examined. The regional characteristics, variability, regional controlling factors and the interrelations of the atmospheric water budget components are investigated. The surface evapotranspiration was created using the High Resolution Land Data Assimilation System (HRLDAS) with the satellite-observed rainfall and vegetation fraction. HRLDAS evapotranspiration shows significant similarity with in situ observations and MODIS satellite-observed evapotranspiration. Result highlights the fundamental importance of evapotranspiration over northwest and southeast India on atmospheric water balance. The investigation shows that the surface net radiation controls the annual evapotranspiration over those regions, where the surface evapotranspiration is lower than 550 mm. The rainfall and evapotranspiration show a linear relation over the low-rainfall regions (<500 mm/year). Similar result is observed in in NASA GLDAS data (1980-2014). The atmospheric water budget shows annual, seasonal, and intra-seasonal variations. Evapotranspiration does not show a high intra-seasonal variability as compared to other water budget components. The coupling among the water budget anomalies is investigated. The results show that regional inter-annual evapotranspiration anomalies are not exactly in phase with rainfall anomalies; it is strongly influenced by the surface conditions and other atmospheric forcing (like surface net radiation). The lead and lag correlation of water budget components show that the water budget anomalies are interrelated in the monsoon season even up to 4 months lead. These results show the important regional interrelation of water budget anomalies on south Asian monsoon.

Space radiation risk limits and Earth-Moon-Mars environmental models

NASA Astrophysics Data System (ADS)

Cucinotta, Francis A.; Hu, Shaowen; Schwadron, Nathan A.; Kozarev, K.; Townsend, Lawrence W.; Kim, Myung-Hee Y.

2010-12-01

We review NASA's short-term and career radiation limits for astronauts and methods for their application to future exploration missions outside of low Earth orbit. Career limits are intended to restrict late occurring health effects and include a 3% risk of exposure-induced death from cancer and new limits for central nervous system and heart disease risks. Short-term dose limits are used to prevent in-flight radiation sickness or death through restriction of the doses to the blood forming organs and to prevent clinically significant cataracts or skin damage through lens and skin dose limits, respectively. Large uncertainties exist in estimating the health risks of space radiation, chiefly the understanding of the radiobiology of heavy ions and dose rate and dose protraction effects, and the limitations in human epidemiology data. To protect against these uncertainties NASA estimates the 95% confidence in the cancer risk projection intervals as part of astronaut flight readiness assessments and mission design. Accurate organ dose and particle spectra models are needed to ensure astronauts stay below radiation limits and to support the goal of narrowing the uncertainties in risk projections. Methodologies for evaluation of space environments, radiation quality, and organ doses to evaluate limits are discussed, and current projections for lunar and Mars missions are described.

Earth's magnetosphere and outer radiation belt under sub-Alfvénic solar wind.

PubMed

Lugaz, Noé; Farrugia, Charles J; Huang, Chia-Lin; Winslow, Reka M; Spence, Harlan E; Schwadron, Nathan A

2016-10-03

The interaction between Earth's magnetic field and the solar wind results in the formation of a collisionless bow shock 60,000-100,000 km upstream of our planet, as long as the solar wind fast magnetosonic Mach (hereafter Mach) number exceeds unity. Here, we present one of those extremely rare instances, when the solar wind Mach number reached steady values <1 for several hours on 17 January 2013. Simultaneous measurements by more than ten spacecraft in the near-Earth environment reveal the evanescence of the bow shock, the sunward motion of the magnetopause and the extremely rapid and intense loss of electrons in the outer radiation belt. This study allows us to directly observe the state of the inner magnetosphere, including the radiation belts during a type of solar wind-magnetosphere coupling which is unusual for planets in our solar system but may be common for close-in extrasolar planets.

Jovian decametric radiation seen from Juno, Cassini, STEREO A, WIND, and Earth-based radio observatories

NASA Astrophysics Data System (ADS)

Imai, M.; Kurth, W. S.; Hospodarsky, G. B.; Bolton, S. J.; Connerney, J. E. P.; Levin, S. M.; Lecacheux, A.; Lamy, L.; Zarka, P.; Clarke, T. E.; Higgins, C. A.

2017-09-01

Jupiter's decametric (DAM) radiation is generated very close to the local gyrofrequency by the electron cyclotron maser instability (CMI). The first two-point common detections of Jovian DAM radiation were made using the Voyager spacecraft and ground-based radio observatories in early 1979, but, due to geometrical constraints and limited flyby duration, a full understanding of the latitudinal beaming of Jovian DAM radiation remains elusive. The stereoscopic DAM radiation viewed from Juno, Cassini, STEREO A, WIND, and Earth-based radio observatories provides a unique opportunity to analyze the CMI emission mechanism and beaming properties.

THE EFFECT OF CLOUD FRACTION ON THE RADIATIVE ENERGY BUDGET: The Satellite-Based GEWEX-SRB Data vs. the Ground-Based BSRN Measurements

NASA Astrophysics Data System (ADS)

Zhang, T.; Stackhouse, P. W.; Gupta, S. K.; Cox, S. J.; Mikovitz, J. C.; Nasa Gewex Srb

2011-12-01

The NASA GEWEX-SRB (Global Energy and Water cycle Experiment - Surface Radiation Budget) project produces and archives shortwave and longwave atmospheric radiation data at the top of the atmosphere (TOA) and the Earth's surface. The archive holds uninterrupted records of shortwave/longwave downward/upward radiative fluxes at 1 degree by 1 degree resolution for the entire globe. The latest version in the archive, Release 3.0, is available as 3-hourly, daily and monthly means, spanning 24.5 years from July 1983 to December 2007. Primary inputs to the models used to produce the data include: shortwave and longwave radiances from International Satellite Cloud Climatology Project (ISCCP) pixel-level (DX) data, cloud and surface properties derived therefrom, temperature and moisture profiles from GEOS-4 reanalysis product obtained from the NASA Global Modeling and Assimilation Office (GMAO), and column ozone amounts constituted from Total Ozone Mapping Spectrometer (TOMS), TIROS Operational Vertical Sounder (TOVS) archives, and Stratospheric Monitoring-group's Ozone Blended Analysis (SMOBA), an assimilation product from NOAA's Climate Prediction Center. The data in the archive have been validated systemically against ground-based measurements which include the Baseline Surface Radiation Network (BSRN) data, the World Radiation Data Centre (WRDC) data, and the Global Energy Balance Archive (GEBA) data, and generally good agreement has been achieved. In addition to all-sky radiative fluxes, the output data include clear-sky fluxes, cloud optical depth, cloud fraction and so on. The BSRN archive also includes observations that can be used to derive the cloud fraction, which provides a means for analyzing and explaining the SRB-BSRN flux differences. In this paper, we focus on the effect of cloud fraction on the surface shortwave flux and the level of agreement between the satellite-based SRB data and the ground-based BSRN data. The satellite and BSRN employ different

SAS 2 observations of the earth albedo gamma radiation above 35 MeV

NASA Technical Reports Server (NTRS)

Thompson, D. J.; Simpson, G. A.; Ozel, M. E.

1981-01-01

The earth albedo gamma radiation above 35 MeV in the equatorial region is investigated using observations from the second Small Astronomy Satellite. The zenith angle distribution of the gamma radiation has a peak toward the horizon which is about an order of magnitude more intense than the radiation coming from the nadir, and nearly two orders of magnitude more intense than the gamma radiation from most parts of the sky. The gamma radiation originating from the western horizon is a factor of four more intense than the radiation from the eastern horizon and a factor of three more intense than that from the northern and southern directions. This reflects the geomagnetic effects on the incident cosmic rays whose interactions produce the albedo gamma rays. The variation of the upcoming gamma ray intensity with vertical cutoff rigidity is consistent with the empirical relationship found by Gur'yan et al. (1979).

A study of the 3D radiative transfer effect in cloudy atmospheres

NASA Astrophysics Data System (ADS)

Okata, M.; Teruyuki, N.; Suzuki, K.

2015-12-01

Evaluation of the effect of clouds in the atmosphere is a significant problem in the Earth's radiation budget study with their large uncertainties of microphysics and the optical properties. In this situation, we still need more investigations of 3D cloud radiative transer problems using not only models but also satellite observational data.For this purpose, we have developed a 3D-Monte-Carlo radiative transfer code that is implemented with various functions compatible with the OpenCLASTR R-Star radiation code for radiance and flux computation, i.e. forward and backward tracing routines, non-linear k-distribution parameterization (Sekiguchi and Nakajima, 2008) for broad band solar flux calculation, and DM-method for flux and TMS-method for upward radiance (Nakajima and Tnaka 1998). We also developed a Minimum cloud Information Deviation Profiling Method (MIDPM) as a method for a construction of 3D cloud field with MODIS/AQUA and CPR/CloudSat data. We then selected a best-matched radar reflectivity factor profile from the library for each of off-nadir pixels of MODIS where CPR profile is not available, by minimizing the deviation between library MODIS parameters and those at the pixel. In this study, we have used three cloud microphysical parameters as key parameters for the MIDPM, i.e. effective particle radius, cloud optical thickness and top of cloud temperature, and estimated 3D cloud radiation budget. We examined the discrepancies between satellite observed and mode-simulated radiances and three cloud microphysical parameter's pattern for studying the effects of cloud optical and microphysical properties on the radiation budget of the cloud-laden atmospheres.

Effects of solar radiation, terrestrial radiation and lunar interior heat flow on surface temperature at the nearside of the Moon: Based on numerical calculation and data analysis

NASA Astrophysics Data System (ADS)

Song, Yutian; Wang, Xueqiang; Bi, Shengshan; Wu, Jiangtao; Huang, Shaopeng

2017-09-01

Surface temperature at the nearside of the Moon (Ts,n) embraces an abundance of valuable information to be explored, and its measurement contributes to studying Earth's energy budget. On a basis of a one-dimensional unsteady heat-transfer model, this paper ran a quantitative calculation that how much the Ts,n varies with the changes of different heat sources, including solar radiation, terrestrial radiation, and lunar interior heat flow. The results reveal that solar radiation always has the most important influence on Ts,n not only during lunar daytime (by means of radiation balance) but also during lunar nighttime (by means of lunar regolith heat conduction). Besides, the effect of terrestrial radiation is also unavoidable, and measuring the variation of lunar nighttime low temperature is exactly helpful in observing Earth outgoing radiation. Accordingly, it is practical to establish a Moon-base observatory on the Moon. For verification, the Apollo 15 mission temperature data was used and analyzed as well. Moreover, other 9 typical lunar areas were selected and the simulation was run one after another in these areas after proper model amendation. It is shown that the polar regions on the Moon are the best areas for establishing Moon-base observatory.

Site selection and directional models of deserts used for ERBE validation targets

NASA Technical Reports Server (NTRS)

Staylor, W. F.

1986-01-01

Broadband shortwave and longwave radiance measurements obtained from the Nimbus 7 Earth Radiation Budget scanner were used to develop reflectance and emittance models for the Sahara, Gibson, and Saudi Deserts. These deserts will serve as in-flight validation targets for the Earth Radiation Budget Experiment being flown on the Earth Radiation Budget Satellite and two National Oceanic and Atmospheric Administration polar satellites. The directional reflectance model derived for the deserts was a function of the sum and product of the cosines of the solar and viewing zenith angles, and thus reciprocity existed between these zenith angles. The emittance model was related by a power law of the cosine of the viewing zenith angle.

A magma ocean and the Earth's internal water budget

NASA Technical Reports Server (NTRS)

Ahrens, Thomas J.

1992-01-01

There are lines of evidence which relate bounds on the primordial water content of the Earth's mantle to a magma ocean and the accompanying Earth accretion process. We assume initially (before a magma ocean could form) that as the Earth accreted, it grew from volatile- (H2O, CO2, NH3, CH4, SO2, plus noble) gas-rich planetesimals, which accreted to form an initial 'primitive accretion core' (PAC). The PAC retained the initial complement of planetesimal gaseous components. Shock wave experiments in which both solid, and more recently, the gaseous components of materials such as serpentine and the Murchison meteorite have demonstrated that planetesimal infall velocities of less than 0.5 km/sec, induce shock pressures of less than 0.5 GPa and result in virtually complete retention of planetary gases.

An Earth Summit in a Large General Education Oceanography Class

NASA Astrophysics Data System (ADS)

Dodson, H.; Prothero, W. A.

2001-12-01

An Earth Summit approach in UCSB's undergraduate physical oceanography course has raised student interest level while it also supports the course goals of increased learner awareness of the process of science, and critical analysis of scientific claims. At the beginning of the quarter, each group of students chooses a country to represent in the Earth Summit. During the course of the quarter, these groups relate each of the class themes to their chosen country. Themes include 1) ocean basins and plate tectonics, 2) atmospheres, oceans and climate, and 3) fisheries. Students acquire and utilize Earth data to support their positions. Earth data sources include the "Our Dynamic Planet" CDROM (http://oceanography.geol.ucsb.edu/ODP_Advert/odp_onepage.htm), NOAA's ocean and climate database (http://ferret.wrc.noaa.gov/las/), WorldWatcher CD (http://www.worldwatcher.northwestern.edu/) and JPL's Seawinds web site (http://haifung.jpl.nasa.gov/index.html). During the atmospheres, oceans and climate theme, students choose from 12 mini-studies that use various kinds of on-line Earth data related to important global or regional phenomena relevant to the course. The Earth datasets that the students access for their analysis include: winds; atmospheric pressure; ocean chemistry; sea surface temperature; solar radiation; precipitation, etc. The first group of 6 mini-studies focus on atmosphere and ocean, and are: 1) global winds and surface currents, 2) atmosphere and ocean interactions, 3) stratospheric ozone depletion, 4) El Nino, 5) Indian monsoon, and 6) deep ocean circulation. The second group focus on the Earth's heat budget and climate and are: 1) influence of man's activities on the climate, 2) the greenhouse effect, 3) seasonal variation and the Earth's heat budget, 4) global warming, 5) paleoclimate, and 6) volcanoes and climate. The students use what they have learned in these mini-studies to address atmospheric and climatic issues pertinent to their specific Earth

Ecosystem Modeling of Biological Processes to Global Budgets

NASA Technical Reports Server (NTRS)

Christopher, Potter S.; Condon, Estelle (Technical Monitor)

2000-01-01

biosphere effects on atmospheric composition is the ecosystem level. These assumptions are the foundation for developing modern emission budgets for biogenic gases such as carbon dioxide, methane, carbon monoxide, isoprene, nitrous and nitric oxide, and ammonia. Such emission budgets commonly include information on seasonal flux patterns, typical diurnal profiles, and spatial resolution of at least one degree latitude/longitude for the globe. On the basis of these budgets, it is possible to compute 'base emission rates' for the major biogenic trace gases from both terrestrial and ocean sources, which may be useful benchmarks for defining the gas production rates of organisms, especially those from early Earth history, which are required to generate a detectable signal on a global atmosphere. This type of analysis is also the starting point for evaluation of the 'biological processes to global gas budget' extrapolation procedure described above for early Earth ecosystems.

Design and "As Flown" Radiation Environments for Materials in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Minow, Joseph; McWilliams, Brett; Altstatt, Richard; Koontz, Steven

2006-01-01

A conservative design approach was adopted by the International Space Station Program for specifying total ionizing radiation dose requirements for use in selecting and qualifying materials for construction of the International Space Station. The total ionizing dose design environment included in SSP 30512 Space Station Ionizing Radiation Design Environment is based on trapped proton and electron fluence derived from the solar maximum versions of the AE-8 and AP-8 models, respectively, specified for a circular orbit at 500 km altitude and 51.7 degree inclination. Since launch, the range of altitudes utilized for Space Station operations vary from a minimum of approximately 330 km to a maximum of approximately 405 km with a mean operational altitude less than 400 km. The design environment, therefore, overestimates the radiation environment because the particle flux in the South Atlantic Anomaly is the primary contributor to radiation dose in low Earth orbit and flux within the Anomaly is altitude dependent. In addition, a 2X multiplier is often applied to the design environment to cover effects from the contributions of galactic cosmic rays, solar energetic particle events, geomagnetic storms, and uncertainties in the trapped radiation models which are not explicitly included in the design environment. Application of this environment may give radiation dose overestimates on the order of 1OX to 30X for materials exposed to the space environment, suggesting that materials originally qualified for ten year exposures on orbit may be used for longer periods without replacement. In this paper we evaluate the "as flown" radiation environments derived from historical records of the ISS flight trajectory since launch and compare the results with the SSP 30512 design environment to document the magnitude of the radiation dose overestimate provided by the design environment. "As flown" environments are obtained from application of the AE-8/AP-8 trapped particle models along

A Dynamic/Anisotropic Low Earth Orbit (LEO) Ionizing Radiation Model

NASA Technical Reports Server (NTRS)

Badavi, Francis F.; West, Katie J.; Nealy, John E.; Wilson, John W.; Abrahms, Briana L.; Luetke, Nathan J.

2006-01-01

The International Space Station (ISS) provides the proving ground for future long duration human activities in space. Ionizing radiation measurements in ISS form the ideal tool for the experimental validation of ionizing radiation environmental models, nuclear transport code algorithms, and nuclear reaction cross sections. Indeed, prior measurements on the Space Transportation System (STS; Shuttle) have provided vital information impacting both the environmental models and the nuclear transport code development by requiring dynamic models of the Low Earth Orbit (LEO) environment. Previous studies using Computer Aided Design (CAD) models of the evolving ISS configurations with Thermo Luminescent Detector (TLD) area monitors, demonstrated that computational dosimetry requires environmental models with accurate non-isotropic as well as dynamic behavior, detailed information on rack loading, and an accurate 6 degree of freedom (DOF) description of ISS trajectory and orientation.

The Influence of Ablation on Radiative Heating for Earth Entry

NASA Technical Reports Server (NTRS)

Johnston, Christopher O.; Gnoffo, Peter A.; Sutton, Kenneth

2008-01-01

Using the coupled ablation and radiation capability recently included in the LAURA flowfield solver, this paper investigates the influence of ablation on the shock-layer radiative heating for Earth entry. The extension of the HARA radiation model, which provides the radiation predictions in LAURA, to treat a gas consisting of the elements C, H, O, and N is discussed. It is shown that the absorption coefficient of air is increased with the introduction of the C and H elements. A simplified shock layer model is studied to show the impact of temperature, as well as the abundance of C and H, on the net absorption or emission from an ablation contaminated boundary layer. It is found that the ablation species reduce the radiative flux in the vacuum ultraviolet, through increased absorption, for all temperatures. However, in the infrared region of the spectrum, the ablation species increase the radiative flux, through strong emission, for temperatures above 3,000 K. Thus, depending on the temperature and abundance of ablation species, the contaminated boundary layer may either provide a net increase or decrease in the radiative flux reaching the wall. To assess the validity of the coupled ablation and radiation LAURA analysis, a previously analyzed Mars-return case (15.24 km/s), which contains significant ablation and radiation coupling, is studied. Exceptional agreement with previous viscous shock-layer results is obtained. A 40% decrease in the radiative flux is predicted for ablation rates equal to 20% of the free-stream mass flux. The Apollo 4 peak-heating case (10.24 km/s) is also studied. For ablation rates up to 3.4% of the free-stream mass flux, the radiative heating is reduced by up to 19%, while the convective heating is reduced by up to 87%. Good agreement with the Apollo 4 radiometer data is obtained by considering absorption in the radiometer cavity. For both the Mars return and the Apollo 4 cases, coupled radiation alone is found to reduce the radiative

Earth's magnetosphere and outer radiation belt under sub-Alfvénic solar wind

PubMed Central

Lugaz, Noé; Farrugia, Charles J.; Huang, Chia-Lin; Winslow, Reka M.; Spence, Harlan E.; Schwadron, Nathan A.

2016-01-01

The interaction between Earth's magnetic field and the solar wind results in the formation of a collisionless bow shock 60,000–100,000 km upstream of our planet, as long as the solar wind fast magnetosonic Mach (hereafter Mach) number exceeds unity. Here, we present one of those extremely rare instances, when the solar wind Mach number reached steady values <1 for several hours on 17 January 2013. Simultaneous measurements by more than ten spacecraft in the near-Earth environment reveal the evanescence of the bow shock, the sunward motion of the magnetopause and the extremely rapid and intense loss of electrons in the outer radiation belt. This study allows us to directly observe the state of the inner magnetosphere, including the radiation belts during a type of solar wind-magnetosphere coupling which is unusual for planets in our solar system but may be common for close-in extrasolar planets. PMID:27694887

Extrapolation of Earth-based solar irradiance measurements to exoatmospheric levels for broad-band and selected absorption-band observations

NASA Technical Reports Server (NTRS)

Reagan, J. A.; Pilewskie, P. A.; Scott-Fleming, I. C.; Hermann, B. M.

1986-01-01

Techniques for extrapolating Earth-based spectral band measurements of directly transmitted solar irradiance to equivalent exoatmospheric signal levels were used to aid in determining system gain settings of the Halogen Occultation Experiment (HALOE) sunsensor system being developed for the NASA Upper Atmosphere Research Satellite and for the Stratospheric Aerosol and Gas (SAGE) 2 instrument on the Earth Radiation Budget Satellite. A band transmittance approach was employed for the HALOE sunsensor which has a broad-band channel determined by the spectral responsivity of a silicon detector. A modified Langley plot approach, assuming a square-root law behavior for the water vapor transmittance, was used for the SAGE-2 940 nm water vapor channel.

New High Energy Electron Component of Earth Radiation Belt

NASA Astrophysics Data System (ADS)

Dmitrenko, V. V.; Galper, A. M.; Gratchev, V. M.; Kirillov-Ugryumov, V. G.; Ulin, S. E.; Voronov, S. A.

The Earth Radiation Belt (ERB) was discovered in the course of the first flights of Russian and American satellites with conventional instruments (gas discharge and scintillation counters), which made it possible to investigate many characteristics of trapped particles and simulate adequate radiation belt models. However, the experimental and theoretical evidence accumulated over recent time, needs more elaborate measurements for its interpretation. These measurements became feasible after the development of devices based on more perfect detectors (solid and gas-filled Cherenkov detectors, magnetic spectrometer, scintillation time-of-flight systems). The evidence requiring new direct measurements in the ERB was obtained in the late 1960s in the course of balloon flights carried out by Cosmophysics Laboratory of the Moscow Engineering and Physics Institute. In these flights a correlation between the high energy electron flux in the upper atmosphere and perturbations ofthe Earth's magnetosphere was established. This phenomenon could be explained assuming there exist high energy electron fluxes in the ERB. High energy electron fluxes in the ERB were recorded for the first time in the direct experiments carried out on board orbital station 'Salyut-6' (orbit altitude - 350 km, inclination 51.6 deg). A scintillation-Cherenkov telescope 'Elena' controlled by cosmonauts was preset to different programmed positions. The measurements were made in the periphery of the ERB, namely, in the part which goes as low as several hundred km in the Brazil Anomaly Region (BRA). The flux of electrons with energies above 30 MeV was up to 104 (m2s sr)-1.

How well can we measure Earth's Energy Imbalance?

NASA Astrophysics Data System (ADS)

Hakuba, M. Z.; Stephens, G. L.; Landerer, F. W.; Webb, F.; Bettadpur, S. V.; Tapley, B. D.; Christophe, B.; Foulon, B.

2017-12-01

The direct measurement of Earth's energy imbalance (EEI) is one of the greatest challenges in climate research. The global mean EEI is the integrated value of global warming, while its spatial and temporal variability can tell us about the strength and direction of heat transports and reflects internal climate modes such as ENSO. These heat flows ultimately control the circulation in the atmosphere and ocean, and henceforth the water cycle and habitability of our planet. Current space-born systems measure the radiative components of the global mean energy budget with unprecedented accuracy and stability, but the residual budget derived from them has errors too large to determine the absolute magnitude of EEI. Best estimates of EEI are currently derived from changes in ocean heat content, which are afflicted with horizontal and vertical sampling issues. Hence, we see the need to improve on current approaches in order to circumvent calibration issues that are inevitable in radiometry, and sampling issues that are inevitable when profiling the ocean. We will present alternative methods to estimate the EEI by 1) exploiting existing datasets of ocean mass and sea level height from remote sensing. A combination of such datasets, as for example provided by the GRACE and Jason missions, provides a way of estimating the thermo-steric sea level rise and therefore the thermal expansion of the ocean due to heat uptake. Recent studies suggest the retrieval of ocean heat uptake is possible within acceptable error bounds, although the magnitude and sources of error are yet to be comprehensively defined. 2) To monitor the integrated value of EEI from space, we propose a method that aims at measuring the non-gravitational force due to radiation pressure acting on Earth orbiting spacecrafts. This requires measurements of acceleration at high accuracy. The concept of deriving EEI from radiation pressure has been explored in the past and today's advanced capabilities suggest it is

Solar radiation pressure resonances in Low Earth Orbits

NASA Astrophysics Data System (ADS)

Alessi, Elisa Maria; Schettino, Giulia; Rossi, Alessandro; Valsecchi, Giovanni B.

2018-01-01

The aim of this work is to highlight the crucial role that orbital resonances associated with solar radiation pressure can have in Low Earth Orbit. We review the corresponding literature, and provide an analytical tool to estimate the maximum eccentricity which can be achieved for well-defined initial conditions. We then compare the results obtained with the simplified model with the results obtained with a more comprehensive dynamical model. The analysis has important implications both from a theoretical point of view, because it shows that the role of some resonances was underestimated in the past, and also from a practical point of view in the perspective of passive deorbiting solutions for satellites at the end-of-life.

The Terrestrial Planet Finder coronagraph dynamics error budget

NASA Technical Reports Server (NTRS)

Shaklan, Stuart B.; Marchen, Luis; Green, Joseph J.; Lay, Oliver P.

2005-01-01

The Terrestrial Planet Finder Coronagraph (TPF-C) demands extreme wave front control and stability to achieve its goal of detecting earth-like planets around nearby stars. We describe the performance models and error budget used to evaluate image plane contrast and derive engineering requirements for this challenging optical system.

Observed Budgets for the Global Climate

NASA Astrophysics Data System (ADS)

Kottek, M.; Haimberger, L.; Rubel, F.; Hantel, M.

2003-04-01

A global dataset for selected budget quantities specifying the present climate for the period 1991-1995 has been compiled. This dataset is an essential component of the new climate volume within the series Landolt Boernstein - Numerical Data and Functional Relationships in Science and Technology, to be published this year. Budget quantities are those that appear in a budget equation. Emphasis in this collection is placed on observational data of both in situ and remotely sensed quantities. The fields are presented as monthly means with a uniform space resolution of one degree. Main focus is on climatologically relevant state and flux quantities at the earth's surface and at the top of atmosphere. Some secondary and complex climate elements are also presented (e.g. tornadoe frequency). The progress of this collection as compared to other climate datasets is, apart from the quality of the input data, that all fields are presented in standardized form as far as possible. Further, visualization loops of the global fields in various projections will be available for the user in the eventual book. For some budget quantities, e.g. precipitation, it has been necessary to merge data from different sources; insufficiently observed parameters have been supplemented through the ECMWF ERA-40 reanalyses. If all quantities of a budget have been evaluated the gross residual represents an estimate of data quality. For example, the global water budget residual is found to be up to 30 % depending on the used data. This suggests that the observation of global climate parameters needs further improvement.

The WCRP/GEWEX Surface Radiation Budget Project Release 2: An Assessment of Surface Fluxes at 1 Degree Resolution

NASA Technical Reports Server (NTRS)

Stackhouse, P. W., Jr.; Gupta, S. K.; Cox, S. J.; Chiacchio, M.; Mikovitz, J. C.

2004-01-01

The U.S. National Aeronautics and Space Administration (NASA) based Surface Radiation Budget (SRB) Project in association with the World Climate Research Programme Global Energy and Water Cycle Experiment (WCRP/GEWEX) is preparing a new 1 deg x 1 deg horizontal resolution product for distribution scheduled for release in early 2001. The new release contains several significant upgrades from the previous version. This paper summarizes the most significant upgrades and presents validation results as an assessment of the new data set.

Jupiter's Decameter Radiation as Viewed from Juno, Cassini, WIND, STEREO A, and Earth-Based Radio Observatories

NASA Astrophysics Data System (ADS)

Imai, Masafumi; Kurth, William S.; Hospodarsky, George B.; Bolton, Scott J.; Connerney, John E. P.; Levin, Steven M.; Clarke, Tracy E.; Higgins, Charles A.

2017-04-01

Jupiter is the dominant auroral radio source in our solar system, producing decameter (DAM) radiation (from a few to 40 MHz) with a flux density of up to 10-19 W/(m2Hz). Jovian DAM non-thermal radiation above 10 MHz is readily observed by Earth-based radio telescopes that are limited at lower frequencies by terrestrial ionospheric conditions and radio frequency interference. In contrast, frequencies observed by spacecraft depend upon receiver capability and the ambient solar wind plasma frequency. Observations of DAM from widely separated observers can be used to investigate the geometrical properties of the beam and learn about the generation mechanism. The first multi-observer observations of Jovian DAM emission were made using the Voyager spacecraft and ground-based radio telescopes in early 1979, but, due to geometrical constraints and limited flyby duration, a full understanding of the latitudinal beaming of Jovian DAM radiation remains elusive. This understanding is sorely needed to confirm DAM generation by the electron cyclotron maser instability, the widely assumed generation mechanism. Juno first detected Jovian DAM emissions on May 5, 2016, on approach to the Jovian system, initiating a new opportunity to perform observations of Jovian DAM radiation with Juno, Cassini, WIND, STEREO A, and Earth-based radio observatories (Long Wavelength Array Station One (LWA1) in New Mexico, USA, and Nançay Decameter Array (NDA) in France). These observers are widely distributed throughout our solar system and span a broad frequency range of 3.5 to 40.5 MHz. Juno resides in orbit at Jupiter, Cassini at Saturn, WIND around Earth, STEREO A in 1 AU orbit, and LWA1 and NDA at Earth. Juno's unique polar trajectory is expected to facilitate extraordinary stereoscopic observations of Jovian DAM, leading to a much improved understanding of the latitudinal beaming of Jovian DAM.

Solar Irradiance Changes And Photobiological Effects At Earth's Surface Following Astrophysical Ionizing Radiation Events

NASA Astrophysics Data System (ADS)

Thomas, Brian; Neale, Patrick

2016-01-01

Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth for decades. Although there is some direct biological damage on the surface from redistributed radiation several studies have indicated that the greatest long term threat is from ozone depletion and subsequent heightened solar ultraviolet (UV) radiation. It is known that organisms exposed to this irradiation experience harmful effects such as sunburn and even direct damage to DNA, proteins, or other cellular structures. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In the present work, we employed a radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light). Using biological weighting functions we have considered a wide range of effects, including: erythema and skin cancer in humans; inhibition of photosynthesis in the diatom Phaeodactylum sp. and dinoflagellate Prorocentrum micans inhibition of carbon fixation in Antarctic phytoplankton; inhibition of growth of oat (Avena sativa L. cv. Otana) seedlings; and cataracts. We found that past work overestimated UVB irradiance, but that relative estimates for increase in exposure to DNA damaging radiation are still similar to our improved calculations. We also found that the intensity of biologically damaging radiation varies widely with organism and specific impact considered; these results have implications for biosphere-level damage following astrophysical ionizing radiation events. When considering changes in surface-level visible light irradiance, we found that, contrary to previous assumptions, a decrease in irradiance is only present for a short time in

Proposed NASA budget cuts planetary science

NASA Astrophysics Data System (ADS)

Balcerak, Ernie

2012-02-01

President Barack Obama's fiscal year (FY) 2013 budget request for NASA would sharply cut planetary science while maintaining other science and exploration priorities. The total proposed FY 2013 budget for NASA is $17.7 billion, a slight decrease (0.33%) from the previous year (see Table 1). This includes $4.9 billion for the Science directorate, a decrease of about 3.2% from the previous year, and about $3.9 billion for the Human Exploration directorate, a n increase of about $200 million over FY 2012. The latter would include about $2.8 million for development of a new heavy-lift rocket system, known as the Space Launch System (SLS), to take humans beyond low-Earth orbit, along with the Orion crew vehicle.

Isotope composition and volume of Earth's early oceans.

PubMed

Pope, Emily C; Bird, Dennis K; Rosing, Minik T

2012-03-20

Oxygen and hydrogen isotope compositions of Earth's seawater are controlled by volatile fluxes among mantle, lithospheric (oceanic and continental crust), and atmospheric reservoirs. Throughout geologic time the oxygen mass budget was likely conserved within these Earth system reservoirs, but hydrogen's was not, as it can escape to space. Isotopic properties of serpentine from the approximately 3.8 Ga Isua Supracrustal Belt in West Greenland are used to characterize hydrogen and oxygen isotope compositions of ancient seawater. Archaean oceans were depleted in deuterium [expressed as δD relative to Vienna standard mean ocean water (VSMOW)] by at most 25 ± 5‰, but oxygen isotope ratios were comparable to modern oceans. Mass balance of the global hydrogen budget constrains the contribution of continental growth and planetary hydrogen loss to the secular evolution of hydrogen isotope ratios in Earth's oceans. Our calculations predict that the oceans of early Earth were up to 26% more voluminous, and atmospheric CH(4) and CO(2) concentrations determined from limits on hydrogen escape to space are consistent with clement conditions on Archaean Earth.

The Langley Parameterized Shortwave Algorithm (LPSA) for Surface Radiation Budget Studies. 1.0

NASA Technical Reports Server (NTRS)

Gupta, Shashi K.; Kratz, David P.; Stackhouse, Paul W., Jr.; Wilber, Anne C.

2001-01-01

An efficient algorithm was developed during the late 1980's and early 1990's by W. F. Staylor at NASA/LaRC for the purpose of deriving shortwave surface radiation budget parameters on a global scale. While the algorithm produced results in good agreement with observations, the lack of proper documentation resulted in a weak acceptance by the science community. The primary purpose of this report is to develop detailed documentation of the algorithm. In the process, the algorithm was modified whenever discrepancies were found between the algorithm and its referenced literature sources. In some instances, assumptions made in the algorithm could not be justified and were replaced with those that were justifiable. The algorithm uses satellite and operational meteorological data for inputs. Most of the original data sources have been replaced by more recent, higher quality data sources, and fluxes are now computed on a higher spatial resolution. Many more changes to the basic radiation scheme and meteorological inputs have been proposed to improve the algorithm and make the product more useful for new research projects. Because of the many changes already in place and more planned for the future, the algorithm has been renamed the Langley Parameterized Shortwave Algorithm (LPSA).

Bridging the Gap between Earth Science and Students: An Integrated Approach using NASA Earth Science Climate Data

NASA Technical Reports Server (NTRS)

Alston, Erica J.; Chambers, Lin H.; Phelps, Carrie S.; Oots, Penny C.; Moore, Susan W.; Diones, Dennis D.

2007-01-01

Under the auspices of the Department of Education's No Child Left Behind (NCLB) Act, beginning in 2007 students will be tested in the science area. There are many techniques that educators can employ to teach students science. The use of authentic materials or in this case authentic data can be an engaging alternative to more traditional methods. An Earth science classroom is a great place for the integration of authentic data and science concepts. The National Aeronautics and Space Administration (NASA) has a wealth of high quality Earth science data available to the general public. For instance, the Atmospheric Science Data Center (ASDC) at NASA s Langley Research Center houses over 800 Earth science data sets related to Earth's radiation budget, clouds, aerosols and tropospheric chemistry. These data sets were produced to increase academic understanding of the natural and anthropogenic factors that influence global climate; however, a major hurdle in using authentic data is the size of the data and data documentation. To facilitate the use of these data sets for educational purposes, the Mentoring and inquirY using NASA Data on Atmospheric and Earth science for Teachers and Amateurs (MY NASA DATA) project has been established to systematically support educational activities at all levels of formal and informal education. The MY NASA DATA project accomplishes this by reducing these large data holdings to microsets that are easily accessible and explored by K-12 educators and students though the project's Web page. MY NASA DATA seeks to ease the difficulty in understanding the jargon-heavy language of Earth science. This manuscript will show how MY NASA DATA provides resources for NCLB implementation in the science area through an overview of the Web site, the different microsets available, the lesson plans and computer tools, and an overview of educational support mechanisms.

First-principles definition and measurement of planetary electromagnetic-energy budget.

PubMed

Mishchenko, Michael I; Lock, James A; Lacis, Andrew A; Travis, Larry D; Cairns, Brian

2016-06-01

The imperative to quantify the Earth's electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this paper we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting-vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated notions of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

First-principles definition and measurement of planetary electromagnetic-energy budget

NASA Astrophysics Data System (ADS)

Mishchenko, M. I.; James, L.; Lacis, A. A.; Travis, L. D.; Cairns, B.

2016-12-01

The imperative to quantify the Earth's electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this talk we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting-vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated concepts of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

First-Principles Definition and Measurement of Planetary Electromagnetic-Energy Budget

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Lock, James A.; Lacis, Andrew A.; Travis, Larry D.; Cairns, Brian

2016-01-01

The imperative to quantify the Earths electromagnetic-energy budget with an extremely high accuracy has been widely recognized but has never been formulated in the framework of fundamental physics. In this paper we give a first-principles definition of the planetary electromagnetic-energy budget using the Poynting- vector formalism and discuss how it can, in principle, be measured. Our derivation is based on an absolute minimum of theoretical assumptions, is free of outdated notions of phenomenological radiometry, and naturally leads to the conceptual formulation of an instrument called the double hemispherical cavity radiometer (DHCR). The practical measurement of the planetary energy budget would require flying a constellation of several dozen planet-orbiting satellites hosting identical well-calibrated DHCRs.

Implications of a reduced Arctic sea ice cover on the large-scale atmospheric energy and moisture budgets

NASA Astrophysics Data System (ADS)

Porter, David Felton

New estimates of the current energy budget of the north polar cap (the region north of 70N) are synthesized by combining data from new atmospheric reanalyses and satellite retrievals. For the period 2000-2005, monthly means from the Clouds and the Earth's Radiant Energy System (CERES) satellite data set are considered to provide the most reliable top-of-atmosphere (TOA) radiation budget. The remaining components of the energy budget, comprising of the energy storage, horizontal convergence of energy, and the net surface flux between the atmospheric and subsurface columns, are compiled using data from the Japanese 25-year Reanalysis Project (JRA) and the NCEP/NCAR Reanalysis (NRA). The annual cycles of energy budget components for the polar cap are fairly consistent between the JRA and NRA, but with some systematic differences. Estimates of the Arctic energy budget from WRF are compared with estimates from reanalyses and satellite observations. Apart from a few systematic shortcomings, WRF sufficiently captures the Arctic energy budget. The major deficiency, with differences from reanalyses and satellite observations as large as 40 W m-2 in summer months, is in the shortwave radiative fluxes at both the surface and top of the atmosphere, due to a specified constant sea ice albedo of 0.8, which is too high during the summer. Finally, the WRF model (version 3.2.0) is used to explore the sensitivity of the large-scale atmospheric circulation to prescribed changes in Arctic sea ice. Observed sea ice fractions and sea surface temperatures (SSTs) from 1996 and 2007, representing years of high and low sea ice extent, respectively, are used as WRF lower boundary conditions. This yields two 15-member ensembles that sample a large range of true climatic variability. Results of the simulations show both local and remote responses to the sea ice reduction. The local response is largest in October and November, dominated by increased turbulent heat fluxes resulting in a

Uncertainty and Sensitivity Analysis of Afterbody Radiative Heating Predictions for Earth Entry

NASA Technical Reports Server (NTRS)

West, Thomas K., IV; Johnston, Christopher O.; Hosder, Serhat

2016-01-01

The objective of this work was to perform sensitivity analysis and uncertainty quantification for afterbody radiative heating predictions of Stardust capsule during Earth entry at peak afterbody radiation conditions. The radiation environment in the afterbody region poses significant challenges for accurate uncertainty quantification and sensitivity analysis due to the complexity of the flow physics, computational cost, and large number of un-certain variables. In this study, first a sparse collocation non-intrusive polynomial chaos approach along with global non-linear sensitivity analysis was used to identify the most significant uncertain variables and reduce the dimensions of the stochastic problem. Then, a total order stochastic expansion was constructed over only the important parameters for an efficient and accurate estimate of the uncertainty in radiation. Based on previous work, 388 uncertain parameters were considered in the radiation model, which came from the thermodynamics, flow field chemistry, and radiation modeling. The sensitivity analysis showed that only four of these variables contributed significantly to afterbody radiation uncertainty, accounting for almost 95% of the uncertainty. These included the electronic- impact excitation rate for N between level 2 and level 5 and rates of three chemical reactions in uencing N, N(+), O, and O(+) number densities in the flow field.

Regional aerosol radiative and hydrological effects over the mid-Atlantic corridor

NASA Astrophysics Data System (ADS)

Creekmore, Torreon N.

A thorough assessment of direct, indirect, and semi-direct influences of aerosols on Earth's energy budget is required to better understand climate and estimate how it may change in the future. Clear-sky surface broadband (measured and modeled) irradiance, spectral aerosol optical depth, heating rate profiles, and non-radiative flux measurements were conducted at a state-of-the-art site, developed by the NOAA-Howard University Center for Atmospheric Sciences (NCAS) program, providing a best estimate of aerosol radiative atmosphere-surface interactions. Methods developed by the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Program were applied to: (1) temporally quantify regional aerosol forcing, (2) to derive an empirical equation describing a relationship between aerosol optical depth and normalized diffuse ratio, (3) evaluate aerosol impacts on atmospheric heating, and (4) evaluate how aerosol forcing impacts may possibly reduce latent and sensible fluxes. Measurements were obtained during the period of May--September for the years of 2005, 2006, and 2007. Atmospheric aerosols are among the key uncertainties affecting the Earth's climate and atmospheric radiative processes. Present-day increases in aerosol concentrations directly, indirectly, and semi-directly impact the Earth's energy budget (i.e., cooling the surface and heating the atmosphere), thereby contributing to climate change. The Howard University Beltsville Site (HUBS) has experienced a greater loss in mean normalized aerosol radiative forcing with time, as observations show a decrease from --0.9 in 2005 to --3.1 and --3.4 W/m2 for 2006 and 2007 respectively, in mean net surface irradiance. The mean normalized aerosol radiative forcing estimated for the period considered was --2.5 W/m2. The reduction in surface solar insolation is due to increased scattering and absorption related to increased aerosol burdens v for the period, promoting surface cooling and atmospheric heating

Cloud Radiative Effect in dependence on Cloud Type

NASA Astrophysics Data System (ADS)

Aebi, Christine; Gröbner, Julian; Kämpfer, Niklaus; Vuilleumier, Laurent

2015-04-01

Radiative transfer of energy in the atmosphere and the influence of clouds on the radiation budget remain the greatest sources of uncertainty in the simulation of climate change. Small changes in cloudiness and radiation can have large impacts on the Earth's climate. In order to assess the opposing effects of clouds on the radiation budget and the corresponding changes, frequent and more precise radiation and cloud observations are necessary. The role of clouds on the surface radiation budget is studied in order to quantify the longwave, shortwave and the total cloud radiative forcing in dependence on the atmospheric composition and cloud type. The study is performed for three different sites in Switzerland at three different altitude levels: Payerne (490 m asl), Davos (1'560 m asl) and Jungfraujoch (3'580 m asl). On the basis of data of visible all-sky camera systems at the three aforementioned stations in Switzerland, up to six different cloud types are distinguished (Cirrus-Cirrostratus, Cirrocumulus-Altocumulus, Stratus-Altostratus, Cumulus, Stratocumulus and Cumulonimbus-Nimbostratus). These cloud types are classified with a modified algorithm of Heinle et al. (2010). This cloud type classifying algorithm is based on a set of statistical features describing the color (spectral features) and the texture of an image (textural features) (Wacker et al. (2015)). The calculation of the fractional cloud cover information is based on spectral information of the all-sky camera data. The radiation data are taken from measurements with pyranometers and pyrgeometers at the different stations. A climatology of a whole year of the shortwave, longwave and total cloud radiative effect and its sensitivity to integrated water vapor, cloud cover and cloud type will be calculated for the three above-mentioned stations in Switzerland. For the calculation of the shortwave and longwave cloud radiative effect the corresponding cloud-free reference models developed at PMOD/WRC will be

Reduced gas accretion on super-Earths and ice giants

NASA Astrophysics Data System (ADS)

Lambrechts, M.; Lega, E.

2017-10-01

A large fraction of giant planets have gaseous envelopes that are limited to about 10% of their total mass budget. Such planets are present in the solar system (Uranus, Neptune) and are frequently observed in short periods around other stars (the so-called super-Earths). In contrast to these observations, theoretical calculations based on the evolution of hydrostatic envelopes argue that such low-mass envelopes cannot be maintained around cores exceeding five Earth masses. Instead, under nominal disk conditions, these planets would acquire massive envelopes through runaway gas accretion within the lifetime of the protoplanetary disk. In this work we show that planetary envelopes are not in hydrostatic balance, which slows down envelope growth. A series of 3D global, radiative hydrodynamical simulations reveal a steady-state gas flow, which enters through the poles and exits in the disk midplane. Gas is pushed through the outer envelope in about ten orbital timescales. In regions of the disk that are not significantly dust-depleted, envelope accretion onto cores of about five Earth masses can get stalled as the gas flow enters the deep interior. Accreted solids sublimate deep in the convective interior, but small opacity-providing grains are trapped in the flow and do not settle, which further prevents rapid envelope accretion. The transition to runaway gas accretion can however be reached when cores grow larger than typical super-Earths, beyond 15 Earth masses, and preferably when disk opacities are below κ = 1 cm2/g. These findings offer an explanation for the typical low-mass envelopes around the cores of super-Earths.

Wave-Particle Interactions in the Earth's Radiation Belts: Recent Advances and Unprecedented Future Opportunities

NASA Astrophysics Data System (ADS)

Li, W.

2017-12-01

In the collisionless heliospheric plasmas, wave-particle interaction is a fundamental physical process in transferring energy and momentum between particles with different species and energies. This presentation focuses on one of the important wave-particle interaction processes: interaction between whistler-mode waves and electrons. Whistler-mode waves have frequencies between proton and electron cyclotron frequency and are ubiquitously present in the heliospheric plasmas including solar wind and planetary magnetospheres. I use Earth's Van Allen radiation belt as "local space laboratory" to discuss the role of whistler-mode waves in energetic electron dynamics using multi-satellite observations, theory and modeling. I further discuss solar wind drivers leading to energetic electron dynamics in the Earth's radiation belts, which is critical in predicting space weather that has broad impacts on our technological systems and society. At last, I discuss the unprecedented future opportunities of exploring space science using multi-satellite observations and state-of-the-art theory and modeling.

Feasibility of modifying the high resolution infrared radiation sounder (HIRS/2) for measuring spectral components of Earth radiation budget

NASA Technical Reports Server (NTRS)

Koenig, E. W.; Holman, K. A.

1980-01-01

The concept of adding four spectral channels to the 20 channel HIRS/2 instrument for the purpose of determining the origin and profile of radiant existence from the Earth's atmosphere is considered. Methods of addition of three channels at 0.5, 1.0 and 1.6 micron m to the present 0.7 micron m visible channel and an 18-25 micron m channel to the present 19 channels spaced from 3.7 micron m to 15 micron m are addressed. Optical components and physical positions were found that permit inclusion of these added channels with negligible effect on the performance of the present 20 channels. Data format changes permit inclusion of the ERB data in the 288 bits allocated to HIRS for each scan element. A lamp and collimating optic assembly may replace one of the on board radiometric black bodies to provide a reference source for the albedo channels. Some increase in instrument dimensions, weight and power will be required to accommodate the modifications.

A method to detect ultra high energy electrons using earth's magnetic field as a radiator

NASA Technical Reports Server (NTRS)

Stephens, S. A.; Balasubrahmanyan, V. K.

1983-01-01

It is pointed out that the detection of electrons with energies exceeding a few TeV, which lose energy rapidly through synchrotron and inverse Compton processes, would provide valuable information on the distribution of sources and on the propagation of cosmic rays in the solar neighborhood. However, it would not be possible to measure the energy spectrum beyond a few TeV with any of the existing experimental techniques. The present investigation is, therefore concerned with the possibility of detecting electrons with energies exceeding a few TeV on the basis of the photons emitted through synchrotron radiation in the earth's magnetic field. Attention is given to the synchrotron radiation of electrons in the earth's magnetic field, detector response and energy estimation, and the characteristics of an ideal detector, capable of detecting photons with energies equal to or greater than 20 keV.

A GCM simulation of the earth-atmosphere radiation balance for winter and summer

NASA Technical Reports Server (NTRS)

Wu, M. L. C.

1979-01-01

The radiation balance of the earth-atmosphere system simulated by using the general circulation model (GCM) of the Laboratory for Atmospheric Sciences (GLAS) is examined in regards to its graphical distribution, zonally-averaged distribution, and global mean. Most of the main features of the radiation balance at the top of the atmosphere are reasonably simulated, with some differences in the detailed structure of the patterns and intensities for both summer and winter in comparison with values as derived from Nimbus and NOAA (National Oceanic and Atmospheric Administration) satellite observations. Both the capability and defects of the model are discussed.

THE OUTER RADIATION BELT OF THE EARTH AT THE ALTITUDE OF 320 KM

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

Vernov, S.N.; Savenko, I.A.; Shavrin, P.I.

1962-11-01

Scintillation and gas-discharge counters on the second Soviet spaceship allowed a detailed investigation of the outer radiation belt near the earth and established its boundaries in relation to longitude. The spaceship orbit was almost circular at an altitude of 306 to 339 km. The energy threshold of the counter channel was 25 kev. (W,D.M.)

Impact of fire on global land surface air temperature and energy budget for the 20th century due to changes within ecosystems

NASA Astrophysics Data System (ADS)

Li, Fang; Lawrence, David M.; Bond-Lamberty, Ben

2017-04-01

Fire is a global phenomenon and tightly interacts with the biosphere and climate. This study provides the first quantitative assessment and understanding of fire’s influence on the global annual land surface air temperature and energy budget through its impact on terrestrial ecosystems. Fire impacts are quantified by comparing fire-on and fire-off simulations with the Community Earth System Model (CESM). Results show that, for the 20th century average, fire-induced changes in terrestrial ecosystems significantly increase global land annual mean surface air temperature by 0.18 °C, decrease surface net radiation and latent heat flux by 1.08 W m-2 and 0.99 W m-2, respectively, and have limited influence on sensible heat flux (-0.11 W m-2) and ground heat flux (+0.02 W m-2). Fire impacts are most clearly seen in the tropical savannas. Our analyses suggest that fire increases surface air temperature predominantly by reducing latent heat flux, mainly due to fire-induced damage to the vegetation canopy, and decreases net radiation primarily because fire-induced surface warming significantly increases upward surface longwave radiation. This study provides an integrated estimate of fire and induced changes in ecosystems, climate, and energy budget at a global scale, and emphasizes the importance of a consistent and integrated understanding of fire effects.

Low Earth orbital atomic oxygen and ultraviolet radiation effects on polymers

NASA Technical Reports Server (NTRS)

Dever, Joyce A.

1991-01-01

Because atomic oxygen and solar ultraviolet radiation present in the low earth orbital (LEO) environment can alter the chemistry of polymers resulting in degradation, their effects and mechanisms of degradation must be determined in order to determine the long term durability of polymeric surfaces to be exposed on missions such as Space Station Freedom. The effects of atomic oxygen on polymers which contain protective coatings must also be explored, since unique damage mechanisms can occur in areas where the protective coatings has failed. Mechanisms can be determined by utilizing results from previous LEO missions, by performing ground based LEO simulation tests and analysis, and by carrying out focussed space experiments. A survey is presented of the interactions and possible damage mechanisms for environmental atomic oxygen and UV radiation exposure of polymers commonly used in LEO.

Linear Energy Transfer (LET) spectra of cosmic radiation in low Earth orbit

NASA Technical Reports Server (NTRS)

Parnell, T. A.; Watts, J. W., Jr.; Akopova, A. B.; Magradze, N. V.; Dudkin, V. E.; Kovalev, E. E.; Potapov, Yu. V.; Benton, E. V.; Frank, A. L.; Benton, E. R.

1995-01-01

Integral linear energy transfer (LET) spectra of cosmic radiation (CR) particles were measured on five Cosmos series spacecraft in low Earth orbit (LEO). Particular emphasis is placed on results of the Cosmos 1887 biosatellite which carried a set of joint U.S.S.R.-U.S.A. radiation experiments involving passive detectors that included thermoluminescent detectors (TLD's), plastic nuclear track detectors (PNTD's), fission foils, nuclear photo-emulsions, etc. which were located both inside and outside the spacecraft. Measured LET spectra are compared with those theoretically calculated. Results show that there is some dependence of LET spectra on orbital parameters. The results are used to estimate the CR quality factor (QF) for the COSMOS 1887 mission.

Comparison of Global Cloud Fraction and TOA Radiation Budgets between the NASA GISS AR5 GCM Simulations and CERES-MODIS Observations

NASA Astrophysics Data System (ADS)

Stanfield, R. E.; Dong, X.; Xi, B.; Del Genio, A. D.; Minnis, P.; Doelling, D.; Loeb, N. G.

2011-12-01

To better advise policymakers, it is necessary for climate models to provide credible predictions of future climates. Meeting this goal requires climate models to successfully simulate the present and past climates. The past, current and future Earth climate has been simulated by the NASA GISS ModelE climate model and has been summarized by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, AR4, 2007). New simulations from the updated AR5 version of the NASA GISS ModelE GCM have been released to the public community and will be included in the IPCC AR5 ensemble of simulations. Due to the recent nature of these simulations, however, they have yet to be extensively validated against observations. To evaluate the GISS AR5 simulated global clouds and TOA radiation budgets, we have collected and processed the NASA CERES and MODIS observations during the period 2000-2005. In detail, the 1ox1o resolution monthly averaged SYN1 product has been used with combined observations from both Terra and Aqua satellites, and degraded to a 2ox2.5o grid box to match the GCM spatial resolution. These observations are temporally interpolated and fit to data from geostationary satellites to provide time continuity. The GISS AR5 products were downloaded from the CMIP5 (Coupled Model Intercomparison Project Phase 5) for the IPCC-AR5. Preliminary comparisons between GISS AR5 simulations and CERES-MODIS observations have shown that although their annual and seasonal mean CFs agree within a few percent, there are significant differences in several climatic regions. For example, the modeled CFs have positive biases in the Arctic, Antarctic, Tropics, and Sahara Desert, but negative biases over the southern middle latitudes (30-65 oS). The OLR, albedo and NET radiation comparisons are similar to the CF comparison.

[An investigation of ionizing radiation dose in a manufacturing enterprise of ion-absorbing type rare earth ore].

PubMed

Zhang, W F; Tang, S H; Tan, Q; Liu, Y M

2016-08-20

Objective: To investigate radioactive source term dose monitoring and estimation results in a manufacturing enterprise of ion-absorbing type rare earth ore and the possible ionizing radiation dose received by its workers. Methods: Ionizing radiation monitoring data of the posts in the control area and supervised area of workplace were collected, and the annual average effective dose directly estimated or estimated using formulas was evaluated and analyzed. Results: In the control area and supervised area of the workplace for this rare earth ore, α surface contamination activity had a maximum value of 0.35 Bq/cm 2 and a minimum value of 0.01 Bq/cm 2 ; β radioactive surface contamination activity had a maximum value of 18.8 Bq/cm 2 and a minimum value of 0.22 Bq/cm 2 . In 14 monitoring points in the workplace, the maximum value of the annual average effective dose of occupational exposure was 1.641 mSv/a, which did not exceed the authorized limit for workers (5 mSv/a) , but exceeded the authorized limit for general personnel (0.25 mSv/a) . The radionuclide specific activity of ionic mixed rare earth oxides was determined to be 0.9. Conclusion: The annual average effective dose of occupational exposure in this enterprise does not exceed the authorized limit for workers, but it exceeds the authorized limit for general personnel. We should pay attention to the focus of the radiation process, especially for public works radiation.

Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit.

PubMed

Chancellor, Jeffery C; Scott, Graham B I; Sutton, Jeffrey P

2014-09-11

Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO). Shielding is an effective countermeasure against solar particle events (SPEs), but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR) nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other "omics" areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts.

Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

PubMed Central

Chancellor, Jeffery C.; Scott, Graham B. I.; Sutton, Jeffrey P.

2014-01-01

Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO). Shielding is an effective countermeasure against solar particle events (SPEs), but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR) nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts. PMID:25370382

Optical radiation measurements II; Proceedings of the Meeting, Orlando, FL, Mar. 27, 28, 1989

NASA Astrophysics Data System (ADS)

Palmer, James M.

1989-09-01

The present conference discusses topics in the characterization of imaging radiometers, laboratory instrumentation, field and spacecraft instrumentation, and quantum and thermal standard detectors. Attention is given to UV radiometric imaging, dual-color radiometer imagery, a novel diode-array radiometer, a novel reference spectrophotometer, radiance calibration of spherical integrators, instrumentation for measurement of spectral goniometric reflectance, and a real-time IR background discrimination radiometer. Also discussed are a multichannel radiometer for atmosphere optical property measurements, the UV spectroradiometric output of a turbojet, characterizations of the Earth Radiation Budget Experiment scanning radiometers, total-radiation thermometry, future directions in Si photodiode self-calibration, and radiometric quality Ge photodiodes.

Atmospheric dynamics and habitability range in Earth-like aquaplanets obliquity simulations

NASA Astrophysics Data System (ADS)

Nowajewski, Priscilla; Rojas, M.; Rojo, P.; Kimeswenger, S.

2018-05-01

We present the evolution of the atmospheric variables that affect planetary climate by increasing the obliquity by using a general circulation model (PlaSim) coupled to a slab ocean with mixed layer flux correction. We increase the obliquity between 30° and 90° in 16 aquaplanets with liquid sea surface and perform the simulation allowing the sea ice cover formation to be a consequence of its atmospheric dynamics. Insolation is maintained constant in each experiment, but changing the obliquity affects the radiation budget and the large scale circulation. Earth-like atmospheric dynamics is observed for planets with obliquity under 54°. Above this value, the latitudinal temperature gradient is reversed giving place to a new regime of jet streams, affecting the shape of Hadley and Ferrel cells and changing the position of the InterTropical Convergence Zone. As humidity and high temperatures determine Earth's habitability, we introduce the wet bulb temperature as an atmospheric index of habitability for Earth-like aquaplanets with above freezing temperatures. The aquaplanets are habitable all year round at all latitudes for values under 54°; above this value habitability decreases toward the poles due to high temperatures.

Radiometric calibration and performance trends of the Clouds and Earth's Radiant Energy System (CERES) instrument sensors onboard the Terra and Aqua spacecraft

NASA Astrophysics Data System (ADS)

Shankar, Mohan; Priestley, Kory; Smith, Nathaniel; Smith, Nitchie; Thomas, Susan; Walikainen, Dale

2015-10-01

The Clouds and Earth's Radiant Energy System (CERES) instruments help to study the impact of clouds on the earth's radiation budget. There are currently five instruments- two each on board Aqua and Terra spacecraft and one on the Suomi NPP spacecraft to measure the earth's reflected shortwave and emitted longwave energy, which represent two components of the earth's radiation energy budget. Flight Models (FM) 1 and 2 are on Terra, FM 3 and 4 are on Aqua, and FM5 is on Suomi NPP. The measurements are made by three sensors on each instrument: a shortwave sensor that measures the 0.3-5 microns wavelength band, a window sensor that measures the water vapor window between 8-12 microns, and a total sensor that measures all incident energy (0.3- >100 microns). The required accuracy of CERES measurements of 0.5% in the longwave and 1% in the shortwave is achieved through an extensive pre-launch ground calibration campaign as well as on-orbit calibration and validation activities. Onorbit calibration is carried out using the Internal Calibration Module (ICM) that consists of a tungsten lamp, blackbodies, and a solar diffuser known as the Mirror Attenuator Mosaic (MAM). The ICM calibration provides information about the stability of the sensors' broadband radiometric gains on-orbit. Several validation studies are conducted in order to monitor the behavior of the instruments in various spectral bands. The CERES Edition-4 data products for the FM1-FM4 instruments incorporate the latest calibration methodologies to improve on the Edition-3 data products. In this paper, we discuss the updated calibration methodology and present some validation studies to demonstrate the improvement in the trends using the CERES Edition-4 data products for all four instruments.

Earth Reflected Solar Radiation Incident upon an Arbitrarily Oriented Spinning Flat Plate

NASA Technical Reports Server (NTRS)

Cunningham, Fred G.

1963-01-01

A general derivation is given for the earth reflected solar radiation input to a flat plate--a solar cell paddle, for example--which is spinning about an axis coincident with the axis of symmetry of the satellite to which it is affixed. The resulting equations are written for the general case so that arbitrary orientations of the spin axis with respect to the earth-satellite line and arbitrary orientations of the normal to the plate with respect to the spin axis can be treated. No attempt is made to perform the resulting integrations because of the complexity of the equations; nor is there any attempt to delineate the integration limits for the general case. However, the equations governing these limits are given. The appendixes contain: the results, in graphical form, of two representative examples; the general computer program for the calculation is given in Fortran notation; and the results of a calculation of the distribution of albedo energy on the proposed Echo II satellite. The value of the mean solar constant used is 1.395 times 10 (sup 4) ergs per centimeters-squared per second; the mean albedo of the earth is assumed to be 0.34; and the earth is assumed to be a diffuse reflector.

7 CFR 3402.14 - Budget and budget narrative.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 15 2010-01-01 2010-01-01 false Budget and budget narrative. 3402.14 Section 3402.14... GRADUATE AND POSTGRADUATE FELLOWSHIP GRANTS PROGRAM Preparation of an Application § 3402.14 Budget and budget narrative. Applicants must prepare the Budget, Form CSREES-2004, and a budget narrative...

The role of the oceans in changes of the Earth's climate system

NASA Astrophysics Data System (ADS)

von Schuckmann, K.

2016-12-01

Any changes to the Earth's climate system affect an imbalance of the Earth's energy budget due to natural or human made climate forcing. The current positive Earth's energy imbalance is mostly caused by human activity, and is driving global warming. Variations in the world's ocean heat storage and its associated volume changes are a key factor to gauge global warming, to assess changes in the Earth's energy budget and to estimate contributions to the global sea level budget. Present-day sea-level rise is one of the major symptoms of the current positive Earth Energy Imbalance. Sea level also responds to natural climate variability that is superimposing and altering the global warming signal. The most prominent signature in the global mean sea level interannual variability is caused by El Niño-Southern Oscillation. It has been also shown that sea level variability in other regions of the Indo-Pacific area significantly alters estimates of the rate of sea level rise, i.e. in the Indonesian archipelago. In summary, improving the accuracy of our estimates of global Earth's climate state and variability is critical for advancing the understanding and prediction of the evolution of our climate, and an overview on recent findings on the role of the global ocean in changes of the Earth's climate system with particular focus on sea level variability in the Indo-Pacific region will be given in this contribution.

Selection of extreme environmental conditions, albedo coefficient and Earth infrared radiation, for polar summer Long Duration Balloon missions

NASA Astrophysics Data System (ADS)

González-Llana, Arturo; González-Bárcena, David; Pérez-Grande, Isabel; Sanz-Andrés, Ángel

2018-07-01

The selection of the extreme thermal environmental conditions -albedo coefficient and Earth infrared radiation- for the thermal design of stratospheric balloon missions is usually based on the methodologies applied in space missions. However, the particularities of stratospheric balloon missions, such as the much higher residence time of the balloon payload over a determined area, make necessary an approach centered in the actual environment the balloon is going to find, in terms of geographic area and season of flight. In this sense, this work is focussed on stratospheric balloon missions circumnavigating the North Pole during the summer period. Pairs of albedo and Earth infrared radiation satellite data restricted to this area and season of interest have been treated statistically. Furthermore, the environmental conditions leading to the extreme temperatures of the payload depend in turn on the surface finish, and more particularly on the ratio between the solar absorptance and the infrared emissivity α/ε. A simple but representative thermal model of a balloon and its payload has been set up in order to identify the pairs of albedo coefficient and Earth infrared radiation leading to extreme temperatures for each value of α/ε.

First Estimates of the Radiative Forcing of Aerosols Generated from Biomass Burning using Satellite Data

NASA Technical Reports Server (NTRS)

Chistopher, Sundar A.; Kliche, Donna V.; Chou, Joyce; Welch, Ronald M.

1996-01-01

Collocated measurements from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner are used to examine the radiative forcing of atmospheric aerosols generated from biomass burning for 13 images in South America. Using the AVHRR, Local Area Coverage (LAC) data, a new technique based on a combination of spectral and textural measures is developed for detecting these aerosols. Then, the instantaneous shortwave, longwave, and net radiative forcing values are computed from the ERBE instantaneous scanner data. Results for the selected samples from 13 images show that the mean instantaneous net radiative forcing for areas with heavy aerosol loading is about -36 W/sq m and that for the optically thin aerosols are about -16 W/sq m. These results, although preliminary, provide the first estimates of radiative forcing of atmospheric aerosols from biomass burning using satellite data.

First Estimates of the Radiative Forcing of Aerosols Generated from Biomass Burning Using Satellite Data

NASA Technical Reports Server (NTRS)

Christopher, Sundar A.; Kliche, Donna A.; Chou, Joyce; Welch, Ronald M.

1996-01-01

Collocated measurements from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner are used to examine the radiative forcing of atmospheric aerosols generated from biomass burning for 13 images in South America. Using the AVHRR, Local Area Coverage (LAC) data, a new technique based on a combination of spectral and textural measures is developed for detecting these aerosols. Then, the instantaneous shortwave, longwave, and net radiative forcing values are computed from the ERBE instantaneous scanner data. Results for the selected samples from 13 images show that the mean instantaneous net radiative forcing for areas with heavy aerosol loading is about -36 W/sq m and that for the optically thin aerosols are about -16 W/sq m. These results, although preliminary, provide the first estimates of radiative forcing of atmospheric aerosols from biomass burning using satellite data.

Exploring uncertainty in the radiative budget of the Antarctic atmospheric boundary layer at Dome C

NASA Astrophysics Data System (ADS)

Veron, D. E.; Schroth, A.; Genthon, C.; Vignon, E.

2017-12-01

In the past two decades, significant advances have been made in observing and modeling the atmospheric boundary layer processes over the Eastern Antarctic plateau. However, there are gaps in understanding related to the radiative and moisture budgets in the very bottom of the ABL. Since 2009, continuous meteorological observations have been made at 6 heights in the bottom 40-m of the atmosphere as part of the CALibration and VAlidation of meteorological and climate models and satellite retrievals (C ALVA) campaign to improve understanding of the atmospheric state over Dome C. A recent case study that is part of the GEWEX Atmospheric Boundary Layer Study, GABLS4, has also focused on the ability of models to simulate stable summertime boundary layers at the same location. As part of the intercomparison, a model derived summertime climatology based on 10-years of PolarWRF simulations over the Eastern Antarctic plateau was developed. Comparisons between these simulations and data from the CALVA campaign suggest that PolarWRF is not capturing the small-scale variations in the longwave heating rate profile near the surface, and so predicts biased surface temperatures relative to observations. Additional work suggests that modifications of the surface snow representations may also be needed. Studies of the sensitivity of these results to changes in the moisture budget are ongoing.

Viscous-shock-layer solutions with coupled radiation and ablation injection for earth entry

NASA Technical Reports Server (NTRS)

Gupta, Roop N.; Lee, Kam-Pui; Moos, James N.; Sutton, Kenneth

1990-01-01

Results are obtained for the forebody of a planetary exploration vehicle entering the earth's atmosphere. A viscous-shock-layer analysis is used assuming the flow to be laminar and in chemical equilibrium. Presented results include coupled radiation and ablation injection. This study further includes the effect of different transport and thermodynamic properties and radiation models. A Lewis number of 1.4 appears adequate for the radiation-dominated flows. Five velocities corresponding to different possible trajectory points at an altitude of 70 km have been further analyzed in detail. Sublimation and radiative equilibrium wall temperatures are employed for cases with and without coupled injection, respectively. For the cases analyzed here, the mass injection rates are small. However, the rates could become large if a lower altitude is used for aerobraking and/or the body size is increased. A comparison of the equilibrium results with finite-rate chemistry calculation shows the flowfield to be in chemical equilibrium.

An intercomparison of longwave measurements by ERBE radiometers on the NOAA-9 and ERBS satellites

NASA Technical Reports Server (NTRS)

House, Frederick B.

1989-01-01

Two instrument modules of each satellite on which the Earth Radiation Budget Experiment (ERBE) is orbiting observe components of the earth radiation budget with three different scales of earth view. An intercomparison of longwave measurements by these instruments provides relative information concerning radiometric performance at satellite altitude, techniques of estimating upwelling exitances, and an end-to-end evaluation of the data processing system. Results indicate that the ERBE radiometers are mildly sensitive to varying thermal loads from the spacecraft and/or the earth-space environment. Radiometric variations at the satellite and methods of data interpretation contribute about equally to the uncertainty of radiant exitances from the earth.

Radiative Transfer Simulations of Earth Spectra as Registered by ROSETTA/VIRTIS

NASA Astrophysics Data System (ADS)

Hurley, Jane; Irwin, P.; Adriani, A.; Moriconi, M.; Oliva, F.; Coradini, A.

2010-10-01

Rosetta, part of ESA's Horizon 2000 programme, will orbit and land on the comet 67P/Churyumov-Gerasimenko in May 2014. However, launched in March 2004, its trajectory has thus far muchly consisted of a series of planetary fly-bys and gravitational assists using Mars (2007) and Earth (March 2005, 2007 and 2009). During these close fly-bys Rosetta captured measurements of these planets - and of particular interest are those registed by the Visual Infrared Thermal Imaging Spectrometer VIRTIS of Earth, which were taken to help calibrate VIRTIS. Rosetta/VIRTIS measures at high spectral resolution from 0.25 - 5.0 microns, a spectral range which has been well studied by Earth observing instruments such as Meteosat Second Generation Spinning Enhanced Visible and Infrared Imager (MSG/SEVIRI) and the Advanced Along-Track Scanning Radiometer (AATSR). Earth observing instruments, whilst having superior spatio-temporal coverage to the data provided during the Rosetta/VIRTIS fly-bys, are typically constrained to measuring in only a few spectral channels. Hence, Rosetta/VIRTIS should yield more detailed spectral information than these instruments - and is a good candidate for intercomparison studies. To this end, the radiative transfer software NEMESIS (Irwin et al., 2009) is employed for the first time on Earth simulations, having been used extensively for other bodies such as Venus, Mars, Jupiter, Saturn, Neptune, Uranus and Titan. This work compares Rosetta/VIRTIS measurements with NEMESIS-simulated spectra, concentrating on quantifying the ability of NEMESIS to reproduce spectral features associated with different surface topographies (such as ocean, desert and vegetation) in combination with clear and cloudy atmospheric states. Preliminary estimations of temperature and trace-species concentrations and distributions are presented as sample products.

Coloration Determination of Spectral Darkening Occurring on a Broadband Earth Observing Radiometer: Application to Clouds and the Earth's Radiant Energy System (CERES)

NASA Technical Reports Server (NTRS)

Matthews, Grant; Priestley, Kory; Loeb, Norman G.; Loukachine, Konstantin; Thomas, Susan; Walikainen, Dale; Wielicki, Bruce A.

2006-01-01

It is estimated that in order to best detect real changes in the Earth s climate system, space based instrumentation measuring the Earth Radiation Budget (ERB) must remain calibrated with a stability of 0.3% per decade. Such stability is beyond the specified accuracy of existing ERB programs such as the Clouds and the Earth s Radiant Energy System (CERES, using three broadband radiometric scanning channels: the shortwave 0.3 - 5microns, total 0.3. > 100microns, and window 8 - 12microns). It has been shown that when in low earth orbit, optical response to blue/UV radiance can be reduced significantly due to UV hardened contaminants deposited on the surface of the optics. Since typical onboard calibration lamps do not emit sufficient energy in the blue/UV region, this darkening is not directly measurable using standard internal calibration techniques. This paper describes a study using a model of contaminant deposition and darkening, in conjunction with in-flight vicarious calibration techniques, to derive the spectral shape of darkening to which a broadband instrument is subjected. Ultimately the model uses the reflectivity of Deep Convective Clouds as a stability metric. The results of the model when applied to the CERES instruments on board the EOS Terra satellite are shown. Given comprehensive validation of the model, these results will allow the CERES spectral responses to be updated accordingly prior to any forthcoming data release in an attempt to reach the optimum stability target that the climate community requires.

Budget update: Future is looking gloomier for science

NASA Astrophysics Data System (ADS)

As the wheels of the new Republican-controlled Congress have been turning, it looks like belts are indeed going to be tighter around U.S. research and development budgets. In mid-March, the House Budget Committee voted to cut $100 billion over the next five years from federal agency budgets and published guidelines for how this could be done. NASA's Earth Observing System and the U.S. Geological Survey were again mentioned as potential targets and so was the National Oceanic and Atmospheric Administration. If the reduction bill goes the legislative mile, the appropriations committees in each house of Congress will have to figure out where the cuts will fall. Republican and Democratic members of the House Science Committee quickly jumped into the traditional fray with their respective “Views and Estimates” on how science dollars should be doled out for fiscal year 1996. President Clinton has also jumped in the budget-cutting game with the release last week of a plan to cut $13 billion from four federal agencies over the next 5 years. In the meantime, a rescission bill for FY 1995 has been on the fast track through Congress. Here are some of the latest highlights:

A preliminary comparison of scanning vs nonscanning radiometer data from Earth Radiation Budget Satellite (ERBS)

NASA Technical Reports Server (NTRS)

Wu, X.; Smith, W. L.; Herman, L. D.

1986-01-01

A cross validation technique is used to simulate the radiation flux detected by the nonscanning wide FOV (WFOV) and medium FOV (MFOV) radiometers on the ERBS by integrating the top of atmosphere spectral radiance recorded with narrow FOV (NFOV) sensors. Consideration is given to both bidirectional and isotropic radiance contributions, including all shortwave and longwave components. A weighting procedure is defined to adjust for missing or inaccurate data records and a coordinate transformation is devised to account for angular discrepancies among the views of the WFOV, MFOV and NFOV sensors. Student t-test values were calculated for values generated for whole orbit average, morning, noon, evening and night subsatellite views.

Mission description and in-flight operations of ERBE instruments on ERBS and NOAA 9 spacecraft, November 1984 - January 1986

NASA Technical Reports Server (NTRS)

Weaver, William L.; Bush, Kathryn A.; Harris, Chris J.; Howerton, Clayton E.; Tolson, Carol J.

1991-01-01

Instruments of the Earth Radiation Budget Experiment (ERBE) are operating on three different Earth orbiting spacecrafts: the Earth Radiation Budget Satellite (ERBS), NOAA-9, and NOAA-10. An overview is presented of the ERBE mission, in-orbit environments, and instrument design and operational features. An overview of science data processing and validation procedures is also presented. In-flight operations are described for the ERBE instruments aboard the ERBS and NOAA-9. Calibration and other operational procedures are described, and operational and instrument housekeeping data are presented and discussed.