GEWEX-CLIVAR: Coordination of U.S. Activities (1998)

NRC, 1998b. A Scientific Strategy for U.S. Participation in the GOALS (Global Ocean-Atmosphere-Land System) Component of the CLIVAR (Climate Variability and Predictability) Programme. National Academy Press, Washington, DC. pp. 69.

B1. “...the [GOALS] panel proposes that the scientific development and implementation of GOALS should be closely coordinated with the Global Energy and Water Cycle Experiment (GEWEX) and the Climate Variability on Decade-to-Century Time Scales (Dec-Cen) programs, thereby contributing to a cohesive and overarching structure consistent with the objectives of the U.S. Global Change Research Program (USGCRP) and international CLIVAR.” (pgs. 3-4)

B2. “Land surface processes, including vegetation and the biosphere, are explicit elements of GOALS and are to be studies in conjunction with GEWEX.” (pg. 6)

B3. “At the higher-frequency end of the spectrum and where land surface processes are more directly involved, GOALS plans on specific interfaces with GEWEX.” (pg. 9)

B4. “Combining the focus of GOALS (seasonal-to-interannual time scales) and those of GEWEX and DecCen, leads to a complete program that addresses key issues concerning the predictability of climate on all time scales--a primary concern of the USGCRP, and the international CLIVAR program of the WCRP.” (pg. 10)

B5. “GOALS should explicitly take into account the activities of these other programs when developing its own strategies so as to minimize redundancies. For example, it is important to note that GOALS emphasizes process studies, empirical studies, and observations focused on ocean-atmosphere coupling. This emphasis is proposed because another component of the WCRP, GEWEX, is a complementary climate research program that focuses on the role of land in the coupled ocean-atmosphere-land system. Therefore, the panel recommends that GOALS should actively pursue collaborative research with GEWEX as the means of conducting process studies in select land areas. Close collaboration with GEWEX is also envisaged to develop pilot long-term monitoring systems covering the role of the land and land-surface processes in climate variability. ” (pg. 19)

B6. Table 6-1:

Key “State” and “External (or Forcing)” Variables -- [those supplied by GEWEX or those that are an investigative focus of GEWEX are listed] (pg. 26)

• radiation: net surface and downwelling long- and short-wave; net top of the atmosphere

• precipitation

• vertical and spatial distributions of atmospheric water in its liquid and vapor phases

• soil moisture

• water runoff

• evaporation

• evapotranspiration

B7. “To be useful to other components of WCRP/CLIVAR and the USGCRP, long-term observations must be quality controlled, organized, and ultimately processed into gridded fields for use by scientists involved in GOALS research, as well as other programs such as DecCen and GEWEX.” (pg. 27)

B8. “The panel highlights several issues that need to be considered seriously in the implementation of the observing systems and networks supporting the scientific objectives of GOALS. They are important for the programs complementary to GOALS such as GEWEX and DecCen.” (pg. 28)

B9. “To help define and develop appropriate ocean, atmosphere, and land observing elements for incorporation into the GCOS, the GOALS Panel recommends that close coordination should be maintained with the DecCen component of CLIVAR and other WCRP programs such as GEWEX and ACSYS.” (pg. 28)

B10. “Complementary land process studies are being proposed under the framework of GOALS, but their implementation will be coordinated with and undertaken by GEWEX. An example is the GEWEX Asian Monsoon Experiment (GAME) under which land surface processes are being investigated in a variety of climatic regimes ranging from tropical forests to tundra.” (pg. 34)

B11. “The panel recommends that GOALS process experiments should be coordinated either with GEWEX process studies, such as GAME and the GEWEX Continental-Scale International Project (GCIP), or with DecCen process studies. Close coordination is considered necessary with climate-related U.S. and international programs to achieve mutual objectives. This is important for producing a critical mass of observations as well as for sharing the funding of process studies.” (pg. 35)

B12. “The impacts of local and remote forcing on the hydrological cycle (especially over land) should be determined, and feedbacks to the atmosphere through changes in ground hydrology and other land surface processes should be estimated. The role of snow cover and soil moisture over land in inducing anomalies in large-scale circulations should likewise be determined.” (pg. 38)

B13. “The improvement of Land Surface Process Models (LSPMs) to a stage where they represent adequately the interaction between the land surface and vegetation and the atmosphere is necessary... On the large scale, LSPMs should also be constructed to account for the significant time lags between winter snow or ice and their melt in spring, leading to ground water recharge in spring. The coupling of land surface processes with the oceans through river outflow should also be examined. On shorter time scales, especially in the tropics, LSPMs should be able to characterize moisture recycling processes. Evapotranspiration through the vegetation canopy and albedo changes and feedbacks are important processes that have to be modeled better. ” (pg. 41)

B14. “With regard to applications and human dimensions, the panel recommends that auxiliary models be designed to predict societally important quantities not routinely produced by seasonal-to-interannual climate forecast models. These models can be based on both empirical and physical techniques and could involve predictions of quantities including regional rainfall and storm track activity that are not predicted by intermediate models or, for example, the likelihood of tropical storms or extreme events that are not predicted by coupled GCMs. ” (pg. 42)

B15. “Other activities recommended by the [GOALS] panel include experiments to determine the contributions of the upper-ocean heat content (tropical and extratropical) and land surface moisture and heat content to the sources of memory for seasonal-to-interannual variability.” (pg. 43)

B16. “The activities recommended by the panel to be carried out to investigate vulnerability and impacts of seasonal-to-interannual variability include determination of the following:

...

4. impact of seasonal-to-interannual variability on water resources and the implications of this variability for flood control and conservation decisions;” (pg. 47)

B17. “The [GOALS] panel also underscores that strong interfaces need to be sustained with GEWEX because of the common interests in global energy and water cycles and their role in seasonal-to-interannual variability. This common interest of GOALS and GEWEX includes overlapping objectives aimed at improving the understanding and modeling of processes and in interpreting predictions in terms of terrestrial water resources. ” (pg. 55)

B18. “Specifically, the panel recommends partnerships between GOALS and the following programs:

1. GEWEX-GCIP, PACS, and its international program VAMOS--The former process study focuses on energy and water exchange between the atmosphere and the land. PACS, on the other hand, seeks linkages between variations in the tropical oceans adjacent to the Americas and seasonal-to-interannual climate variability in the Americas. Internationally, the VAMOS subprogram under CLIVAR also focuses on the variability of the American monsoons. ” (pgs. 55-56)

B19. “The following are recommended as examples that will facilitate the coordination necessary between GOALS and other programs:

1. coordinated organization of scientific meetings (or workshops) and program development meetings and announcements of opportunity, with a focus on topics of common interest between programs, for example, a scientific meeting sponsored jointly by GOALS and GEWEX (Joint NRC panel meetings have proven useful in the past and should be encouraged.);

2. exchange of data between programs and coordinated development of data sets of relevance and value to more than one program (For example, time series of surface forcing variables for atmospheric models should be made ;universally available for use in sensitivity and predictability tests.);

3. exchange, testing, or coordinated development of process sub-models that are relevant to research undertaken in more than one program (For example, land-atmosphere interaction sub-models might be involved in the case of GOALS and GEWEX, and atmospheric radiation transfer sub-models in the case of GOALS, ARM, and GEWEX.);

...

5. coordination of the timing of complementary regional studies (For example there might be simultaneous intensive observations such as between PACS and GCIP, PACS and the Land-Biosphere-Atmosphere program, and the GOALS JASMINE and other process studies, such as GAME.);

...

8. coordination of the calibration and evaluation of remotely sensed variables of relevance and value to more than one program (Examples include the calibration and evaluation of TRMM and EOS data by observations from in situ monitoring under GOALS and GEWEX.);

9. 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 (For example, GOALS's scientists could participate in workshops that address the development and testing of coupled land-atmosphere sub-models under GEWEX or the development of atmospheric radiation transfer sub-models under ARM.);

10. joint development of coupled ocean-atmosphere-land models (For example, GOALS and GEWEX might undertake the joint development of global-scale, coupled ocean-atmosphere models that include nested mesoscale models in specific regions.);

11. joint activities addressing regional issues and the local application/interpretation of the seasonal-to-interannual predictions fostered under GOALS (For example, GOALS and GCIP could work jointly to create a capability to predict and interpret seasonal-to-interannual variability of meteorological fields covering North America.)...” (pgs. 57-59)