On December 22, Dr. Ghassem Asrar, Associate Administrator of the Office of Earth Science, announced the selection of winning proposals for end-to-end small spacecraft missions known as Earth System Science Pathfinders (ESSPs). Under the terms of the competition, these ESSP mission proposals included not only instruments and data analysis, but also spacecraft, launch vehicle, and satellite command and control systems, and were cost capped at $90 M for the first mission and $120 M for the second mission. These principal investigator-led missions are to be developed from approval to launch in just three years (for the first mission) with little direct NASA oversight, and are expected to yield exciting new science that complements, but does not duplicate, the science from NASA's Earth Observing System (EOS). Furthermore, NASA policy precludes development of any mission that competes with or duplicates other capabilities available from foreign or commercial partners.
The Pathfinder Instruments for Cloud and Aerosol Spaceborne ObservationsClimatologie Etendue des Nuages et des Aerosols (PICASSO-CENA), led by Dr. David Winker of NASA Langley Research Center, Hampton, VA, was selected as the primary second mission for full-scale development. It is designed to address the role of clouds and aerosol particles and their impact on the Earth's radiation budgeta balance of solar energy reaching the Earth, and lost to space, that ultimately controls the temperature of the Earth.
PICASSO-CENA will employ a dual-wavelength polarization-sensitive lidar to profile the vertical distribution of clouds and aerosol particles, along with a high-spectral-resolution oxygen A-band spectrometer, an imaging infrared radiometer, and a high-spatial-resolution wide-field camera. PICASSO-CENA, together with the Earth Observing System satellites, will establish the scientific basis for understanding the dynamics and energetics of the Earth's atmosphere in support of short-term weather and long-term climate forecasts. Its orbit is optimized to coincide closely with EOS PM-1 and especially the MODIS and CERES sensors onboard the spacecraft.
In addition to PICASSO-CENA, NASA has selected two additional ESSP missions, CloudSat and VOLCAM (the Volcanic Ash Mission), as alternate missions. CloudSat and VOLCAM will go through an extended development and technology assessment prior to the decision of which mission will be the primary and alternate.
CloudSat is a mission focused on understanding the role of optically thick clouds on the Earth's radiation budget, and is led by Prof. Graeme Stephens of Colorado State University. CloudSat would use an advanced cloud-profiling radar to provide information on the vertical structure of highly dynamic tropical cloud systems. This new radar would enable measurements of cloud properties for the first time on a global basis, revolutionizing our understanding of cloud-related issues.
VOLCAM is a pathfinder mission for demonstrating the operational and scientific applications of monitoring volcanic clouds and aerosols from a geostationary orbit, and is led by Dr. Arlin Krueger of NASA Goddard Space Flight Center. Volcanic clouds are a potential hazard to jet aircraft, and have, on several occasions, damaged commercial airliners when volcanic ash has been injected into the airline engines. In addition to causing air traffic hazards, volcanic eruptions increase the amount of aerosol particles in the upper atmosphere that leads, in turn, to less solar radiation reaching the Earth's surface and subsequently cooler temperatures at the Earth's surface. The information provided by VOLCAM would provide data to better represent the transport of volcanic aerosols in global atmospheric-circulation models of the Earth's climate and weather.
The ESSP selections were made from a group of ten proposals that were evaluated in the second phase of a rigorous, two-phased selection process that began eight months ago with the April 1998 release of the second ESSP Announcement of Opportunity (AO). The original announcement generated 20 proposals that were subsequently evaluated on the basis of scientific merit. An initial ESSP AO resulted in the selection of two missions now under full-scale development for flight, namely the Vegetation Canopy Lidar (VCL) and the Gravity Recovery and Climate Experiment (GRACE). VCL will launch in 2000, while GRACE will be launched in 2001.
The estimated mission cost of PICASSO-CENA, including launch vehicle, is $173.5 million. NASA will provide $117.4 million, with France providing $56.1 million. The spacecraft will be launched in 2003. The provision by France of a PROTEUS spacecraft, the infrared imaging system, and science analysis support make this mission a true international partnership. The estimated mission cost of CloudSat would be $144.6 million, with NASA contributing $119.6 million. Collaboration with Canada is being explored for the provision of critical components for CloudSat's cloud-profiling radar. The estimated mission cost of VOLCAM would be $48 million, of which NASA would provide $45 million, and other U.S. government agencies would provide $3 million. The VOLCAM mission is intended to be launched using a "piggyback" approach involving one of several potential spacecraft of opportunity.
NASA plans to announce an opportunity for continuation as well as new research in the EOS Interdisciplinary Science (IDS) Program. This will involve a complete recompetition of research projects and will require a proposal from all PIs wishing to continue or initiate new research. This recompetition will include the original, long-term IDS grants, the more-recent three-year investigations, and the JGOFS Science investigations. The NRA should be released to the public around mid-May with proposals due in mid-August. Both mail and panel reviews are scheduled to be completed by the end of October, and the first six-month's worth of funding will begin approximately March 1, 2000. Subsequent yearly funding periods will begin on January 1 to minimize the uncosted carryover problem.
The scientific scope of this NASA Research Announcement (NRA) will cover the six areas of scientific emphasis in the forthcoming Earth Science Enterprise (ESE) Science Implementation Plan, namely the Global Carbon Cycle, the Global Energy and Water Cycle, Climate Variability and Prediction, Atmospheric Chemistry, Solid Earth Science, and other Interdisciplinary Science.
Finally, I am happy to report that Dr. Mark Schoeberl has once again agreed to serve as EOS Chemistry Project Scientist, replacing Dr. P. K. Bhartia, who has served effectively as Chemistry Project Scientist for the past two years. Dr. Schoeberl is a nationally recognized scientist with expertise in stratospheric dynamics, satellite instrumentation, and data analysis. He has extensive knowledge of issues of atmospheric chemistry, has previously served as EOS Chemistry and UARS Project Scientist as well as chair of the EOS Atmospheres Panel, and is Principal Investigator of an EOS Interdisciplinary Science Investigation. He is a senior scientist in the Laboratory for Atmospheres at Goddard Space Flight Center. Mark will have two deputy Project Scientists, Dr. Anne Douglass and Mr. Ernie Hilsenrath. The Chemistry Project Science Office has established six working groups to address the following specific issues: science, data systems, flight operations, education/outreach, algorithm development, and validation.