Cloud Properties of CERES-MODIS Edition 4 and CERES-VIIRS Edition 1

The Clouds and Earth's Radiant Energy System (CERES) analyzes MODerate-resolution Imaging Spectroradiometer (MODIS) data and Visible Infrared Imaging Radiometer Suite (VIIRS) to derive cloud properties that are combine with aerosol and CERES broadband flux data to create a multi-parameter data set for climate study. CERES has produced over 15 years of data from Terra and over 13 years of data from Aqua using the CERES-MODIS Edition-2 cloud retrieval algorithm. A recently revised algorithm, CERESMODIS Edition 4, has been developed and is now generating enhanced cloud data for climate research (over 10 years for Terra and 8 years for Aqua). New multispectral retrievals of properties are included along with a multilayer cloud retrieval system. Cloud microphysical properties are reported at 3 wavelengths, 0.65, 1.24, and 2.1 microns to enable better estimates of the vertical profiles of cloud water contents. Cloud properties over snow are retrieved using the 1.24-micron channel. A new CERES-VIIRS cloud retrieval package was developed for the VIIRS spectral complement and is currently producing the CERES-VIIRS Edition 1 cloud dataset. The results from CERES-MODIS Edition 4 and CERES-VIIRS Edition 1 are presented and compared with each other and other datasets, including CALIPSO, CloudSat and the CERES-MODIS Edition-2 results

Techniques for Improving the Performance of Multiple Writer Memory Protocols in Distributed Shared Memory Systems

Distributed shared memory systems are an important tool for developingand executing parallel computations on networks of workstations. However, their performance strongly depends on the efficient implementation of concurrent access totheshared data. We propose several techniques withthepotential of improving the performance of important basic protocols utilized in the existing distributed shared memory systems

OAI-PMH Architecture for the NASA Langley Research Center Atmospheric Science Data Center

Abstract. We present the architectural decisions involved in adding an Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) interface to the NASA Langley Research Center Atmospheric Science Data Center (ASDC). We review four possible implementation strategies and discuss the implications of our choice. The ASDC differs from most OAI-PMH implementations because of its complex data model, large size (1.3 petabytes) of its Earth Science data holdings and its rate of data acquisition (>20 terabytes / month)