20 A Review of the USGCRP and NASA's MTPE/EOS NASA's Earth Observing System The National Aeronautics and Space Administration (NASA) Earth Observing System (EOS) should reflect the integrated observational strategy called for above. A series of previous reviews reshaped the program and guided it toward more responsiveness to scientific needs, greater resiliency, and increased opportunities for the introduction of new technology. In the plans presented to the present review, smaller spacecraft were scheduled to follow the AM-1, PM-1, and Chemistry-1 (Chem-1) missions. Furthermore, there was a shift by NASA in 1994 and 1995 from a fixed series of 9 missions involving intermediate-class spacecraft to a mixed fleet of 21 missions exploiting small to medium-class spacecraft. Our review supports that trend. The present review also has confirmed that continued evolution is essential for successful implementation of NASA's Earth Observing System; therefore, the capability for future evolution must be maintained. In keeping with the above recommendation that the USGCRP develop an integrated observational strategy, and in anticipation of the advancement in understanding that will be achieved during this first phase of the EOS program, NASA, in concert with the USGCRP community, should consider carefully the observational strategy appropriate for the post-2004 era. Specific consideration must be given to the balance between monitoring, which requires certain long-term, calibrated measurements, and focused process studies, which may be accomplished in shorter periods. NASA's plans for biennial assessments are consistent with this recommendation and should also help ensure that the near-term observational strategy remains technologically current and scientifically relevant. The present review has concluded, however, that structural changes to the near-term EOS missions beyond the limits achieved in the 1995 reshaping exercise would cause severe program dislocations. Further budgetary reductions or imposed constraints on technical options could mean the elimination of key sensors, slips in schedule, loss of data continuity, and the elimination of advanced technology development that could enhance future research and lower costs. Our review has concluded that a shift to smaller platforms for the first group of instruments would be premature, since it could eliminate key measurements. As a result of technological advances, new scientific insights, programmatic changes by NASA in 1994 and 1995, and the evolving needs of the USGCRP as a whole, it is now appropriate to rebalance the program across space assets, in situ measurements, modeling and process studies, and the data and information management system. This rebalancing must be done carefully and must fully recognize the importance of certain calibrated long-term measurements for the USGCRP. The basis for this rebalanced EOS observational strategy is the 1995 reshaping of NASA's Earth Observing System. Recommendations The USGCRP as a whole, and NASA's Mission to Planet Earth (MTPE) Program specifically, should maintain a science-driven approach to observation and information FINDINGS AND RECOMMENDATIONS 21 technology that employs current technology while investing in the development of new technology with clear applications to support the program's specific scientific priorities. NASA should implement most of the near-term components of MTPE/EOS, including Landsat 7, AM-1, PM-1, and the Tropical Rainfall Measuring Mission (TRMM), without delay or reduction in overall observing capability. In situ observational programs, process studies, and large-scale modeling activities should be expanded (e.g., through coordinated field programs focused on high-priority scientific issues and utilization of advances in technology). NASA should develop advanced technologies to reduce the costs of continuing the essential observations initiated by the AM-1, PM-1, and Chem-1 missions. · Because global mapping of tropospheric ozone is central for understanding and monitoring changes in the chemistry of the troposphere, the tropospheric component of the Chemistry-1 mission should be focused on global measurements of tropospheric ozone and its precursors in conjunction with the international ozone network. NASA should evaluate the capabilities of both space-based and in situ approaches to define the best scientific framework for obtaining critical information on ozone precursors in order to interpret tropospheric ozone trends. This evaluation must involve a wide spectrum of the scientific community. In addition, the evaluation should consider the critical aspects of the coupling between the chemistry of the troposphere and the stratosphere and the contributions from the European ENVISAT mission. An overall need to simplify and focus the Chem-1 mission and thereby reduce its cost and complexity must be recognized; however, the Chemistry-1 mission should not be delayed. Coordination with Other Space Remote-Sensing Programs Convergence of observing activities among the programs of U.S. agencies and those of other nations offers the potential for significant savings. However, the current convergence planning process does not have the charter or authority to consider the scientific requirements of 22 Recommendations A Review of the USGCRP and NASA's MTPE/EOS · Science requirements should be considered for inclusion in the specifications for the converged NOAA/Defense Meteorological Satellite Program system. In 1996, a scientific and technical review of the federal convergence activities should be conducted with special attention to their connection to the USGCRP. Small-Satellite and Advanced Technologies Those small satellites that have relatively low costs and short development times may provide mission and programmatic flexibility that can stimulate innovation. They can also provide a means to introduce new technology and conduct focused observing missions. The reshaped 1995 MTPE/EOS program anticipates the application of such satellites where appropriate. In some cases, physics, economics, and engineering constraints may preclude the application of small satellites. A balanced architecture for MTPE employs satellites of various sizes as appropriate to scientific needs. Recommendations • NASA should explore the possibility of using advanced technologies on small satellites for measuring tropospheric aerosols and winds, soil moisture, and other key parameters through laser, radar, and other advanced technologies. The Earth sciences component of the New Millennium Program (NMP) should be integrated into the Mission to Planet Earth Program; it should be science driven and not treated as a separate technology program. A small-satellite program should recognize two linked challenges: 1. to develop capabilities that will lower mission costs; and 2. to develop measurement capabilities that advance our observational capabilities in critical priority areas in Earth system science and global change. Again, however, any shift in observational strategy and its implementation must be done carefully and must fully recognize the importance of certain calibrated long-term measurements for the USGCRP. FINDINGS AND RECOMMENDATIONS Practical Applications of EOS 23 MTPE/EOS, including the TRMM, Landsat 7, AM-1, PM-1, Chem-1, and the associated smaller missions, represents significant advances over previous space observation systems. The capabilities of these systems will contribute to practical applications such as natural hazards mitigation, water resources management, and food and fiber production, as well as advances in the Earth sciences. Recommendation The capabilities of MTPE/EOS should be exploited fully via enhanced public access to the information products. EOS Data and Information System The EOS Data and Information System (EOSDIS) is an essential component of the EOS program for linking space and ground observations and converting them into accessible geophysical information that will contribute to new scientific understanding. Originally designed by NASA as a centrally controlled and operated system to meet ambitious performance and reliability requirements, the system was redesigned after a National Research Council (NRC) review as a logically distributed system based on a client-server model in order to accommodate evolving computer system concepts and technologies. Despite this improvement, current performance requirements, a centrally controlled system of stand-alone computer centers, and an extensive engineering and management superstructure are stressing the bounds of affordability. Moreover, the committee is concerned that the management structure may not be sufficiently flexible to meet rapidly evolving scientific needs and opportunities. The current system should therefore be reconsidered in light of technological opportunities and possible management efficiencies. The present problems with EOSDIS are not related to engineering concepts. Instead, the concerns are much more fundamental and are related directly to the conceptual model of its operations and management. For EOSDIS to succeed in enabling new levels of achievement in the Earth sciences and applications in a wide range of activities in the public and private sectors, its management must be open and community based. That is, the community of researchers and users must take the lead in making key decisions, and the assignment of responsibilities and evaluations of performance must be based on peer review. The system must encourage innovation and creativity through broad participation of the scientific, public, and private sectors. Recent progress in redesigning the EOSDIS architecture, coupled with extraordinary new capabilities in computer telecommunications and recent experience by the scientific community in the management of large and diverse data sets, now permits a significant change in the r 24 A Review of the USGCRP and NASA's MTPE/EOS conceptual model that governs the management and operation of the system. Thus, although the initial processing (e.g., through geo-located and calibrated radiances at the spacecraft) of the data flowing from spacecraft should remain with NASA and could be conducted largely at existing centers, the subsequent processing and creation of products useful in science and applications should be distributed widely and thereby take advantage of the concepts and technology involved in the rapid growth of the Internet and the World Wide Web. Thus, the current distributed client-server design of EOSDIS is responsive to community needs, and its engineering development, and should continue. However, the Committee on Global Change Research believes that the EOSDIS management and operations concept should be redefined to involve the broad user community effectively. Recommendations The components of the EOSDIS now under development for flight control, data downlink, and initial processing should be retained but streamlined. Responsibility for product generation, publication, and user services should be transferred to a federation of partners selected through a competitive process open to all. Representative actions to respond to these recommendations are given in Appendix F with the aim of aiding NASA, the EOS investigators, and EOSDIS contractors in designing and conducting a collaborative study of the feasibility and cost of the proposed approach. Clearly these recommendations imply a major change in EOSDIS management and operations. Under the proposed concept, the initial processing of observational data from EOS spacecraft would remain the responsibility of NASA. After a transition period, however, the responsibility for generating products and accounting for interdependencies among instruments would be distributed through a competitive process to a federation that might include government, academic, and private sector entities. Members of the federation would receive geophysically located, calibrated radiances over the Internet or via overnight express; process the data to higher levels, resolving any necessary interdependencies; create appropriate data products; and make them available to users over the Internet or by shipment of media. Among the higher-level data products that would be produced and distributed in this manner would be EOS Standard Data Products. To be successful, this approach must incorporate community leadership and acceptance of responsibility in decisionmaking, and it must encourage innovation and creativity by providing users with ready access to scientifically meaningful data sets. The new approach must be based on powerful incentives, permissive standards that encourage wide participation and electronic publication of results, and meaningful criteria for assessing the performance of the partners |