GEWEX—CLIVAR

Coordination of U.S. Activities

In December 1998, scientists and policymakers from the United States will travel to Paris to participate in a planning meeting for the international Climate Variability and Predictability (CLIVAR) Programme. Some of the key purposes of the meeting are to set intergovernmental and interprogram directions and priorities for CLIVAR and to develop mechanisms to facilitate CLIVAR implementation, ensuring that its whole is more than the sum of its parts. The objectives of CLIVAR are to describe and understand climate variability on seasonal to centennial time scales, identify the physical processes responsible, including anthropogenic effects, and develop modeling and predictive capabilities where practicable. In this brief report we, the National Research Council's Global Energy and Water Cycle Experiment (GEWEX) Panel, discuss issues pertaining to the coordination of U.S. activities within GEWEX and between GEWEX and CLIVAR that we hope will be considered in the deliberations associated with the Paris CLIVAR meeting.

As two of the primary drivers of the climate system, energy and water constitute and connect the myriad of climate phenomena to be explored in CLIVAR. If the objectives of CLIVAR are to be realized, then the complementary strengths of GEWEX must be exploited. These strengths lie in global observations of key components of the water and energy cycles, as well as in interpretation of land surface–atmosphere interactions and the physics and human dimensions of surface hydrology. GEWEX also focuses on the processes through which clouds, water vapor, aerosols, and radiation force climate on time scales within those broadly spanned by CLIVAR.

Several recent NRC reports have extensively documented the necessity of GEWEX-related research to the various components of CLIVAR. These reports are: Decade-to-Century-Scale Climate Variability and Change: A Science Strategy (NRC, 1998a); A Scientific Strategy for U.S. Participation in the GOALS (Global Ocean-Atmosphere-Land System) Component of the CLIVAR (Climate Variability and Predictability) Programme (NRC, 1998b); Global Environmental Change: Research Pathways for the Next Decade -- Overview (NRC, 1998c); The Atmospheric Sciences: Entering the Twenty-First Century (NRC, 1998d); and GCIP: A Review of Progress and Opportunities (NRC, 1998e). They specifically identify the improvements in understanding of the processes, properties, and observations of the water and energy cycles that are needed to effectively advance climate research on all time scales, including:

  • calibration and evaluation of remotely-sensed variables of the hydrological and energy budgets (A9, B7, E2, E3);1

  • cloud–water-vapor–radiation interactions (A1, A5, A6, A8, A9, A10, D4, D7, D8, D9, E4);

    1  

    The letter/number combinations given in parentheses correspond to the citations attached to the end of this document. A=Dec-Cen, B=GOALS, C=Pathways, D=21st Century, E=GCIP.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 1
GEWEX—CLIVAR: Coordination of U.S. Activities GEWEX—CLIVAR Coordination of U.S. Activities In December 1998, scientists and policymakers from the United States will travel to Paris to participate in a planning meeting for the international Climate Variability and Predictability (CLIVAR) Programme. Some of the key purposes of the meeting are to set intergovernmental and interprogram directions and priorities for CLIVAR and to develop mechanisms to facilitate CLIVAR implementation, ensuring that its whole is more than the sum of its parts. The objectives of CLIVAR are to describe and understand climate variability on seasonal to centennial time scales, identify the physical processes responsible, including anthropogenic effects, and develop modeling and predictive capabilities where practicable. In this brief report we, the National Research Council's Global Energy and Water Cycle Experiment (GEWEX) Panel, discuss issues pertaining to the coordination of U.S. activities within GEWEX and between GEWEX and CLIVAR that we hope will be considered in the deliberations associated with the Paris CLIVAR meeting. As two of the primary drivers of the climate system, energy and water constitute and connect the myriad of climate phenomena to be explored in CLIVAR. If the objectives of CLIVAR are to be realized, then the complementary strengths of GEWEX must be exploited. These strengths lie in global observations of key components of the water and energy cycles, as well as in interpretation of land surface–atmosphere interactions and the physics and human dimensions of surface hydrology. GEWEX also focuses on the processes through which clouds, water vapor, aerosols, and radiation force climate on time scales within those broadly spanned by CLIVAR. Several recent NRC reports have extensively documented the necessity of GEWEX-related research to the various components of CLIVAR. These reports are: Decade-to-Century-Scale Climate Variability and Change: A Science Strategy (NRC, 1998a); A Scientific Strategy for U.S. Participation in the GOALS (Global Ocean-Atmosphere-Land System) Component of the CLIVAR (Climate Variability and Predictability) Programme (NRC, 1998b); Global Environmental Change: Research Pathways for the Next Decade -- Overview (NRC, 1998c); The Atmospheric Sciences: Entering the Twenty-First Century (NRC, 1998d); and GCIP: A Review of Progress and Opportunities (NRC, 1998e). They specifically identify the improvements in understanding of the processes, properties, and observations of the water and energy cycles that are needed to effectively advance climate research on all time scales, including: calibration and evaluation of remotely-sensed variables of the hydrological and energy budgets (A9, B7, E2, E3);1 cloud–water-vapor–radiation interactions (A1, A5, A6, A8, A9, A10, D4, D7, D8, D9, E4); 1   The letter/number combinations given in parentheses correspond to the citations attached to the end of this document. A=Dec-Cen, B=GOALS, C=Pathways, D=21st Century, E=GCIP.

OCR for page 1
GEWEX—CLIVAR: Coordination of U.S. Activities mechanisms and processes of aerosols' impact on the Earth's radiation budget, including their indirect effects (A4, A5); land–atmosphere interactions, including soil moisture, vegetation, and snow and ice feedbacks and anthropogenic forcing (A6, A8, A9, A10, A13, B2, B3, B10, B12, B15, C1, C2, D1, D5, D11, D12, D14, E3); effects of land surface conditions on large-scale circulation (A8, A12, B12, E3); rates, storage, redistribution, and cycling of freshwater; important variables include precipitation, evapotranspiration, soil moisture, and runoff (A3, A5, A7, A9, A10, B6, C4, C5, D8, D10, E1, E3); vertical and horizontal distribution of clouds and water vapor and their changes through time (A7, A9, A15, B6, D3, D4, D8, D9); patterns, mechanisms, and prediction of drought and flooding (A9, A10, C2, D2, E5); effects of freshwater balance on salinity, and thus oceanic stratification/convection (A9, A11); model parameterization and prediction of the aforementioned large-and sub-grid-scale processes (A5, A8, A10, A14, B13, B14, C2, D6, D8, D11, E1, E2, E4); hydrological applications and human dimensions (B14, B16, C3, E1, E2, E6). GEWEX addresses all of these components through the following three foci: (1) Hydrometeorology Projects, which include the GEWEX Continental-Scale International Project (GCIP) and the International Satellite Land-Surface Climatology Project (ISLSCP); (2) Radiation Projects, which include the International Satellite Cloud Climatology Project (ISCCP), the Surface Radiation Budget (SRB) Project, the Global Water Vapor Project (GVaP), the Global Precipitation Climatology Project (GPCP), the Baseline Surface Radiation Network (BSRN), and the Global Aerosol Climatology Project (GACP); and (3) Modeling and Prediction Projects, which include the GEWEX Cloud System Study (GCSS) and the Project for Intercomparison of Land-Surface Parameterization Schemes (PILPS). Currently, funding decisions for these activities are made on an ad hoc, agency-by-agency basis. An increase in overall coordination of U.S. GEWEX activities and between these activities and CLIVAR could help better meet the broad needs of the U.S. research and policy communities by establishing interagency priorities and ensuring efficient allocation of resources to scientific objectives. The elements of GEWEX and CLIVAR listed above are related pieces of the same climate system puzzle that must be addressed in its entirety to gain the greatest utility from individual advances. As stated in the CLIVAR Initial Implementation Plan (WCRP, 1998; pg. A-25), “so complementary are GEWEX and CLIVAR that it will be essential for CLIVAR to develop close working relationships with all of the component projects of GEWEX, which are “process-related” projects, each of which also has the development of global data sets as a key ingredient.” The importance of developing effective coupling mechanisms between the various facets of GEWEX and CLIVAR is repeatedly emphasized by the Dec-Cen, GOALS, 21st Century, and GCIP reports (A2, A9, A16, B1, B2, B3, B4, B5, B7, B8, B9, B10, B11, B17, B18, B19, D13, E3, E6). This coupling is succinctly encapsulated in the following statements from the Dec-Cen and GOALS reports: “Issues related to... common processes and patterns warrant particular attention, and a dec-cen program that is highly coordinated with GOALS and GEWEX would enable them to be studied most effectively. ” (A16) “Combining the focus of GOALS... and those of GEWEX and DecCen, leads to a complete program that addresses key issues concerning the predictability of climate on all time

OCR for page 1
GEWEX—CLIVAR: Coordination of U.S. Activities scales—a primary concern of the USGCRP, and the international CLIVAR program of the WCRP.” (B4) The GOALS report makes several specific recommendations as to how these common interests between GEWEX and GOALS (and, by extension, CLIVAR) might be facilitated: coordinated organization of scientific meetings, program development meetings, and announcements of opportunity; exchange of data between programs and coordinated development of data sets of relevance and value to more than one program; exchange, testing, or coordinated development of process sub-models that are relevant to research undertaken in more than one program; coordination of the timing of complementary regional studies; coordination of the calibration and evaluation of remotely sensed variables of relevance and value to more than one program; interprogram support in the form of advice and guidance in the case of activities that are properly fostered within one program but also address the objectives of another program joint development of coupled ocean-atmosphere-land models; and joint activities addressing regional issues and the local application/interpretation of the seasonal-to-interannual predictions fostered under GOALS (B19). There is no interagency mechanism within the United States to ensure that this type of coupling will occur, nor is there one to ensure that the individual GEWEX activities within the United States are coordinated. A high degree of coordination between GEWEX- and CLIVAR-related activities would help ensure that the advances in one program directly feed into the other, minimize duplication of effort, and promote the most efficient avenues for progress. Despite the somewhat higher infrastructural burden that may come with enhanced coordination, the reality is that programs such as GEWEX and CLIVAR cannot work collaterally without having collateral infrastructures. One practicable vehicle for bringing about the necessary inter- and intra-program coupling may be the establishment of a U.S. GEWEX program office that parallels and is closely integrated with the one being discussed for CLIVAR. Whatever integrating approach is chosen, the terms of reference that are established should include coordination between GEWEX and CLIVAR. This coordination must, from the outset, be vigorously and consistently applied; otherwise, the common promise of GEWEX and CLIVAR is not likely to be fully realized. We hope that the considerations raised here are kept in mind during the preparation and participation in the Paris meeting, and will be considered in subsequent interagency deliberations.