The 2007 National Research Council (NRC) Decadal Survey report, "Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond, " provides the basis for the future direction of NASA’s space-based Earth observation system. Missions were ranked according to scientific merit, contributions to long-term observational records, societal benefits, affordability, and technological readiness. The four missions recommended for earliest implementation by NASA were classified as “Tier 1” missions. The Soil Moisture Active-Passive (SMAP) and the Ice, Cloud, and land Elevation Satellite (ICESat-II) missions will be implemented first, with Launch Readiness Dates (LRD) of 2014 and 2015, respectively. CLARREO and the Deformation, Ecosystem Structure, and Dynamics of Ice (DESDynI) are the remaining Tier 1 missions with a LRD of 2018.

NASA will implement these Decadal Survey missions as directed missions, prioritized as defined by the NRC. Langley Research Center (LaRC) will lead the CLARREO mission working with the Program Scientist and Program Executives at NASA HQ, and the Earth Systematic Missions Program Office. The CLARREO Project team successfully completed a Mission Concept Review in fall 2010. The team defined the mission’s science purposes and requirements and a conceptual mission design that demonstrated CLARREO's readiness to proceed into Phase A.

Decadal Survey recommendations represent the integration of community input on the future direction of space-based Earth science; therefore, NASA will continue to engage the scientific community to refine mission requirements during the planning for CLARREO. In addition to the NRC Decadal Survey, a summary of the policy documents that support the science goals of the CLARREO mission can be found here. 

The baseline CLARREO mission as described in the Decadal Survey can be found here.

CLARREO is recommended as a joint NASA/NOAA mission. NOAA will contribute the total and spectral solar irradiance measurements and the Earth energy budget climate data records by flying the Total Solar Irradiance Sensor (TSIS) and the Clouds and the Earth’s Radiant Energy System (CERES) sensors. The NASA portion involves the measurement of spectrally resolved thermal IR and reflected solar radiation at high absolute accuracy.