BOX 2.1 ONGOING CONTRIBUTIONS FROM NASA’S EARTH SCIENCE EXTENDED MISSIONS
NASA’s aging Earth science satellite fleet continues to support many advances in Earth science and applications. Some recent examples include the following:1
• Contributing to the accuracy of weather forecasts and warnings;
• Extending and improving the record of sea-level measurement through continuation of the Jason mission using the precise geodetic infrastructure maintained largely by NASA (Figure 2.1.1);
• Obtaining unique perspectives on water mass changes, including ice loss and the water stored in major river basins around the world, through continuation of the GRACE missions (Figure 2.1.2);
• Continuing the record of stratospheric ozone depletion and recovery through continuation of the Aura mission;
• Understanding the link between fires and air quality through continuation of the Terra, Aqua, and Aura missions;
• Maintaining a continuous, precise measure of the solar energy reaching Earth through continuation of the Solar Radiation and Climate Experiment (SORCE);
• Providing ongoing observations for improved hurricane prediction through continuation of the Tropical Rainfall Measuring Mission (TRMM);
• Determining the relationship between Earth's radiation budget and cloud systems and precipitation, and characterizing clouds' microphysics, morphology, and convection through the continuation of CloudSat;
• Collecting the only civilian high-spectral-resolution imagery available through the continuation of EO-1 and 36 bands of global multispectral environmental imagery through the Moderate Resolution imaging Spectroradiometer (MODIS) on Terra and Aqua;
• Producing a high-quality time series of global sea-surface topography through the continuation of the Ocean Surface Topography Mission (OSTM);
• Measuring cloud optical depth and cloud depth and detecting cloud occurrence through the continuation of the Cloud-Aerosol Lidarand infrared Pathfinder Satellite Observation (CALIPSO) satellite; and
• Estimating wind speed and direction over the ocean through the continuation of the Quick Scatterometer (QuikSCAT).
data have shown encouraging results (Figure 2.1). In October 2011, the NPOESS Preparatory Project was successfully launched, and in December 2011 the first images from its VIIRS instrument were acquired.
LDCM is intended to replace the aging Landsat 7 mission to provide continuity of land cover measurement. Although the 2007 decadal survey recommended securing such a replacement before 2012,7 LDCM is currently slated for launch no earlier than December 2012. This delay was in part due to the congressionally directed addition of the thermal infrared sensor (TIRS) to the platform. GPM, recommended in the survey to “launch in or before 2012” to ensure continuity of precipitation measurements, is now targeted
7 National Research Council, Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond, 2007, p. 6.