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Climate Data Records: From Environmental Satellites E Previous NRC Recommendations Report Recommendations Global Environmental Change: Research Pathways for the Next Decade The strategy for obtaining long-term observations designed to define the magnitude and character of Earth system change must be reassessed. Priority must be given to identifying and obtaining accurate data on key variables carefully selected in view of the most critical science questions and practically feasible measurement capabilities. The USGCRP must revitalize its strategy for the data systems used for (NRC, 1998) global change research. Emphasis must be placed on designing and selecting flexible and innovative systems that appropriately reflect focused responsibility for data character that provide open access to the scientific community and the public, and that rapidly evolve to exploit technological developments. In particular, the USGCRP must closely monitor the progress of the innovative “federation” concept for data systems. Adequacy of Climate Observing Systems Stabilize the existing observational capability. Identify critical variables that are either inadequately or not measured at all. Build climate observing requirements into the operational programs as (NRC, 1998) a high priority. Revamp existing climate research programs and some climate-critical parts of operational observing programs through the implementation of the ten principles of climate monitoring. Establish a funded activity for the development, implementation, and operation of climate-specific observational programs.
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Climate Data Records: From Environmental Satellites Report Recommendations Issues in the Integration of Research and Operational Satellite Systems for Climate Research: Part I. Science and Design (NRC, 2000) Climate research and monitoring capabilities should be balanced with the requirements for operational weather observation and forecasting within an overall U.S. strategy for future satellite observing systems. The Integrated Program Office for NPOESS should give increased consideration to the use of NPOESS for climate research and monitoring. The NASA Earth Science Enterprise should continue to play an active role in the acquisition and analysis of systematic measurements for climate research as well as in the provision of new technology for NPOESS. Joint research and operational opportunities such as the NPOESS Preparatory Project (NPP) should become a permanent part of the U.S. Earth observing remote sensing strategy. Ensuring the Climate Record from the NPP and NPOESS Meteorological Satellites (NRC, 2000) NOAA should begin now to develop and implement the capability to preserve in perpetuity the basic satellite measurements. NOAA should guarantee climate researchers affordable access to all raw data records in the long-term archive, with an emphasis on large-volume data access. NASA, in cooperation with NOAA, should support the development and evaluation of CDRs, as well as their refinement through data processing. NOAA and NASA should define and develop a basic set of user services and tools to meet specific functions for the science community, with NOAA assuming increasing responsibility for this activity as data migrates to the long-term archive. NASA, in cooperation with the Integrated Program Office, should develop the NPOESS Preparatory Project as an integral component of a climate data system. NOAA, in cooperation with NASA, should invest in early, limited capability prototypes for both long-term archiving and the NPP data system. NASA and NOAA should develop and support activities that will enable a blend of distributed and centralized data and information services for climate research.
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Climate Data Records: From Environmental Satellites Report Recommendations Issues in the Integration of Research and Operational Satellite Systems for Climate Research: Part II. Implementation (NRC, 2000) Data should be supported by metadata that carefully document sensor performance history and data processing algorithms. The research community and government agencies should take the initiative and begin planning for a research-oriented NPOESS climate data system and the associated science participation. Quality assessment should be an intrinsic part of operational data production and should be provided in the form of metadata with the data product. Radiometric characterization of the Moon should be continued and possibly expanded to include measurements made at multiple institutions in order to verify the NASA results. If the new reflectance calibration paradigm is adopted, then the objective of the lunar characterization program should be to measure changes in the relative reflectance as a function of the phase and position of Earth, the Sun, and the Moon rather than absolute spectral radiance. The system should have the ability to reprocess large data sets as understanding of sensor performance, algorithms, and Earth science improves. Examples of sources of new information that would warrant data reprocessing include the discovery of processing errors, the detection of sensor calibration drift, the availability of better ancillary data sets, and better geophysical models. The results of sensitivity studies on the parameters in the data product algorithms should be summarized in a requirements document that specifies the characterization measurements for each channel in the sensor. Blanket specifications covering all channels should be avoided unless justified by the sensitivity studies. Competitive selection of instrument science teams should be adopted to follow the progress of the instrument from design and fabrication through integration, launch, operation, and finally, data archiving, thereby promoting more thorough instrument characterization. Science teams responsible for algorithm development, data set continuity, and calibration and validation should be selected via an open, peer-reviewed process (in contrast to the approach taken with the operational integrated data processing system [IDPS] and algorithms, which are being developed by sensor contractors for NPOESS). Validation, an essential part of the information system, should be undertaken for each data product or data record to provide a quantitative estimate of the accuracy of the product over the range of environmental conditions for which the product is provided.
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Climate Data Records: From Environmental Satellites Report Recommendations Reconciling Observations of Global Temperature Change (NRC, 2000) The nations of the world should implement a substantially improved temperature monitoring system that ensures the continuity and quality of critically important data sets. The scientific community should perform a more comprehensive analysis of uncertainties inherent in the surface, radiosonde, and satellite data sets. Natural as well as human-induced changes should be taken into account in climate model simulations of atmospheric temperature variability on decade-to-decade time scales. The scientific community should explore the possibility of exploiting the sophisticated protocols that are now routinely used to ensure the quality and consistency of the data ingested into the operational numerical weather prediction models to improve the reliability of the data sets used to monitor global climate change. Improving Atmospheric Temperature Monitoring Capabilities (NRC, 2000) NESDIS should create a web site that includes information on spacecraft and instrument condition and changes that are of interest for the construction of CDRs. In addition to the official NESDIS TIROS Operational Anomaly Reports (TOAR), this site should be interactive to allow climate investigators to communicate their findings and opinions concerning the behavior of specific instruments and/or channels. The site should be well organized, with cross-referencing by category, and should include a good search capability to enable interested parties to find what they want. An attempt should be made to hierarchically construct the site so that issues judged by NESDIS to be of greatest importance to the climate record are most prominently featured. The information contained on this web site would become part of the permanent metadata record for each instrument. NESDIS should take responsibility for the construction and validation of CDR-quality bulk-layer temperature time series from the SSU and AMSU for the analysis of stratospheric climate variations and trends. NESDIS should establish for each POES operational instrument a structure by which the communication of information may be assured as CDRs are developed and refined. This could be implemented with the establishment of an ad hoc group of individuals who are involved in some way with the development of the instrument and the CDRs. Sponsored meetings or workshops, possibly with published proceedings, would help ensure that the right mix of people have access to one another. Another approach could be the formal establishment of, for example, an MSU/AMSU Climate Science Team which would afford the members the opportunity to deal with issues of calibration, validation, long-term stability, and future requirements for deep-layer atmospheric temperature (as well as other microwave-based products). The team could also advise NESDIS/NCDC on issues of data storage, data access, and which significant products to archive.
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Climate Data Records: From Environmental Satellites Report Recommendations A network performance monitoring system to identify both random errors and time-dependent biases in both space-based and in situ observing systems would enable NOAA and the scientific community to identify and correct errors as soon as possible in these critical observing systems. These diagnostics should become part of the metadata associated with the observations. NOAA should reinvigorate its efforts to “ensure a long-term climate record” (NOAA, 1995). This perspective should permeate the full range of activities related to climate observation, including instrument design and specification, instrument siting, specification of observing methods, data and metadata archiving, production and validation of CDRs, data analysis, and dissemination of products. NOAA should take responsibility for identifying proven CDRs and ensuring that the construction of these be maintained. In addition, NOAA should assume responsibility for supporting and developing the required scientific expertise, documenting the CDR construction methodology, and ensuring that the scientific expertise has been institutionalized, rather than merely residing with individual scientists. It is also important that the time series can be reproduced by future investigators. NOAA should put a high priority on measuring all aspects of the radiometer’s system gain function and baseline offset during prelaunch testing. The usual set of thermal-vacuum tests should be expanded and done more rigorously, and the test results should be made readily available to the scientific community for evaluation. Since the calibration drift seems to be related to temperature, a sufficient number of precision thermistors should be mounted on the various radiometer components (antenna, feedhorn, front-end receiver, detector, etc.) for on-orbit monitoring and drift detection. More robust on-board calibration systems (e.g., additional reference loads) should be considered for future missions. Satellite Observations of the Earth’s Environment (NRC, 2003) NASA and NOAA should jointly work toward and should budget for an adaptive and flexible operational system in order to support the rapid infusion of new satellite observational technologies, the validation of new capabilities, and the implementation of new operational applications. A strong and effective Interagency Transition Office for the planning and coordination of activities of NASA and NOAA in support of transitioning research to operations should be established by and should report to the highest levels of NASA and NOAA. All NASA Earth science satellite missions should be formally evaluated in the early stages of the mission planning process for potential applications to operations in the short, medium, or long term, and resources should be planned for and secured to support appropriate mission transition activities. NOAA and NASA should improve and formalize the process of developing and communicating operational requirements and priorities.
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Climate Data Records: From Environmental Satellites Report Recommendations Planning Climate and Global Change Research: A Review of the Draft U.S. Climate Change Science Program Strategic Plan (NRC, 2003) Ensure the existence of a long-term observing system that provides a more definitive observational foundation to evaluate decadal- to century-scale variability and change. The observation system must include observations of key state variables such as temperature, precipitation, humidity, pressure, clouds, sea ice and snow cover, sea level, SST, carbon fluxes, and soil moisture. More comprehensive regional measurements of greenhouse gases would provide critical information about their local and regional source strengths.
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