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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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An Earth Science Imaging Spectroscopy Mission: the Earth Surface Mineral Dust Source Investigation (emit)
No abstract provided
Overview of the NASA Earth Surface Mineral Dust Source Investigation (EMIT)
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Status of the Earth Surface Mineral Dust Source Investigation Imaging Spectroscopy Mission
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A New Fast Algorithm to Completely Account for Non-Lambertian Surface Reflection of The Earth
Surface bidirectional reflectance distribution function (BRDF) influences not only radiance just about the surface, but that emerging from the top of the atmosphere (TOA). In this study we propose a new, fast and accurate, algorithm CASBIR (correction for anisotropic surface bidirectional reflection) to account for such influences on radiance measured above TOA. This new algorithm is based on a 4-stream theory that separates the radiation field into direct and diffuse components in both upwelling and downwelling directions. This is important because the direct component accounts for a substantial portion of incident radiation under a clear sky, and the BRDF effect is strongest in the reflection of the direct radiation reaching the surface. The model is validated by comparison with a full-scale, vector radiation transfer model for the atmosphere-surface system. The result demonstrates that CASBIR performs very well (with overall relative difference of less than one percent) for all solar and viewing zenith and azimuth angles considered in wavelengths from ultraviolet to near-infrared over three typical, but very different surface types. Application of this algorithm includes both accounting for non-Lambertian surface scattering on the emergent radiation above TOA and a potential approach for surface BRDF retrieval from satellite measured radiance.
Mass Redistribution in the Core and Time-varying Gravity at the Earth's Surface
The Earth's liquid outer core is in convection, as suggested by the existence of the geomagnetic field in much of the Earth's history. One consequence of the convection is the redistribution of mass resulting from relative motion among fluid parcels with slightly different densities. This time dependent mass redistribution inside the core produces a small perturbation on the gravity field of the Earth. With our numerical dynamo solutions, we find that the mass redistribution (and the resultant gravity field) symmetric about the equator is much stronger than that anti-symmetric about the equator. In particular, J(sub 2) component is the strongest. In addition, the gravity field variation increases with the Rayleigh number that measures the driving force for the geodynamo in the core. With reasonable scaling from the current dynamo solutions, we could expect that at the surface of the Earth, the J(sub 2) variation from the core is on the order of l0(exp -16)/year relative to the mean (i.e. spherically symmetric) gravity field of the Earth. The possible shielding effect due to core-mantle boundary pressure variation loading is likely much smaller and is therefore negligible. Our results suggest that time-varying gravity field perturbation due to core mass redistribution may be measured with modem space geodetic observations, which will result a new means of detecting dynamical processes in the Earth's deep interior.
An automated model for predicting the kinetic temperature of the aerospace environment from 100 to 60,000 kilometers above the surface of the earth
Equations for predicting kinetic temperature of aerospace environment from 100 to 60,000 kilometers above earth surface
The Investigations of the Temperature and Spectral Emissivity Characteristics of Cloud Tops and of the Earth's Surface Second Semiannual Progress Report
Temperature and spectral emissivity characteristics of cloud tops and surface of earth
Atmospheric environment - Problems of remote sensing of the earth's surface
Atmospheric difficulties in earth surface remote sensing by satellites, describing absorption, emission and scattering as wavelength functions
The measurement of the surface temperature of the earth technical paper no. 64
Measurement of earth surface temperature by thermistors and airborne radiometers
On the difference between perigee and the point of minimum height above the earth's surface
Difference between perigee and point of minimum height above earth surface
Early Evaluation of the VIIRS Calibration, Cloud Mask and Surface Reflectance Earth Data Records
Surface reflectance is one of the key products fromVIIRS and as withMODIS, is used in developing several higherorder land products. The VIIRS Surface Reflectance (SR) Intermediate Product (IP) is based on the heritageMODIS Collection 5 product (Vermote, El Saleous, & Justice, 2002). The quality and character of surface reflectance depend on the accuracy of the VIIRS Cloud Mask (VCM), the aerosol algorithms and the adequate calibration of the sensor. The focus of this paper is the early evaluation of the VIIRS SR product in the context of the maturity of the operational processing system, the Interface Data Processing System (IDPS). After a brief introduction, the paper presents the calibration performance and the role of the surface reflectance in calibration monitoring. The analysis of the performance of the cloud mask with a focus on vegetation monitoring (no snow conditions) shows typical problems over bright surfaces and high elevation sites. Also discussed is the performance of the aerosol input used in the atmospheric correction and in particular the artifacts generated by the use of the Navy Aerosol Analysis and Prediction System. Early quantitative results of the performance of the SR product over the AERONET sites showthatwith the fewadjustments recommended, the accuracy iswithin the threshold specifications. The analysis of the adequacy of the SR product (Land PEATE adjusted version) in applications of societal benefits is then presented. We conclude with a set of recommendations to ensure consistency and continuity of the JPSS mission with the MODIS Land Climate Data Record.
Gravity gradients on the earth's surface as deduced from satellite orbits
Gravity gradients on earth surface deduced from satellite orbits