January 2014 Issue
Coordinated International Activities On Ocean-Atmosphere Climate Study
By Nico Caltabiano
Roger G. Barry, Director
International CLIVAR Project Office
National Oceanography Centre, U.K.
Climate science has had in the last few months good coverage in the media with the release of the Fifth Assessment Report (AR5) of the United Nations Intergovernmental Panel on Climate Change (IPCC). Behind the scenes and media coverage, the work done by programs and projects on scientific coordination continues at full speed, including responding to changes in the international research agenda.
CLIVAR is the World Climate Research Programme (WCRP) project that addresses Oceans and Climate variability, predictability and change, with a recently redefined focus on ocean-atmosphere interactions. A set of five research challenges have been agreed on since 2012 (Sea Technology, January 2013), but this past year, two others were added after proposals were received from the scientific community: consistency between planetary heat balance and ocean storage, and El Niño Southern Oscillation (ENSO) in a changing climate.
Ocean Heat Balance
Improving the accuracy of our estimates of Earth's climate state and variability is critical for advancing our understanding and prediction of the evolution of the global climate. Determining exact values for energy flows in the Earth system is an area of ongoing climate research. There are independent measurement approaches based on remote sensing and in-situ measurements, and each approach has problems. While deriving budgets of the Earth's climate, errors involved in deriving the single components can accumulate and have major impacts on the accuracy of climate indicators, leading to large imbalances in estimates of Earth's global climate budgets.
There is merit in pursuing all methods because confidence in the results will become high only when they agree, or at least the reasons that they differ are understood. Reconciling the different approaches remains a challenge. Energy balance can also be estimated from climate models, which in turn require validation to provide confidence in their results. Only by using conservation and physical principles can we infer the likely resolution. The main research themes in this topic are: Earth observation measurement constraints on ocean heat budget, in-situ observations of ocean heat content changes, and ocean reanalysis for atmosphere-ocean heat exchange and ocean heat content estimate.
ENSO in a Changing Climate
The El Niño Southern Oscillation is a well-known phenomenon, a naturally occurring fluctuation that originates in the tropical Pacific region and affects ecosystems, agriculture, freshwater supplies, hurricanes and other severe weather events worldwide.
Despite considerable progress in our understanding of the impact of climate change on many of the processes that contribute to ENSO variability, it is not yet possible to say whether ENSO activity will be enhanced or dampened, or if the frequency or character of events will change in the next decades.
Over the past few years, new promising methods have emerged, which can improve ENSO simulations, for example, by bridging ENSO theoretical frameworks and coupled global climate models (CGCM) work. Not only can these new methods and research areas help address the question of whether the characteristics of ENSO are changing in a changing climate, but potentially they can also improve reliability of decadal and centennial-scale climate projections and predictions on seasonal time scales.
It is very important to remember that ocean observations are a crucial component of CLIVAR science, and as the Earth's climate enters a new era where climate change is forced by human activities, it is critically important to maintain an observing system capable of detecting and documenting global climate change. Policy makers and the general public require climate observations to assess the present state of the ocean, cryosphere, atmosphere and land, and to place them in context with the past. To be of large-scale societal and scientific value, these observations must be sustained over many decades and remain of the highest quality. Assessments of the sustained ocean observation network are essential for guiding national and international policies that govern climate-related resources, and agreements aimed at mitigating long-term climate change.
One example is the review of the tropical Pacific observing system, particularly the TAO/TRITON array, and the need to identify a strategy for the future of the system that U.S.'s NOAA and Japan's Agency for Marine-Earth Science and Technology (JAMSTEC) are sponsoring, and of which CLIVAR is a key partner. Three CLIVAR panels (Pacific, Indian Ocean, and Global Synthesis and Observations Panel - GSOP) together with the GCOS/GOOS/WCRP Ocean Observations Panel for Climate (OOPC) and GODAE OceanView are coordinating to assess the impacts of TAO/TRITON data on ocean analysis/reanalysis and operational forecasts.
50th Anniversary of IIOE-2
Also in the Indian Ocean, CLIVAR, the Intergovernmental Oceanographic Commission (IOC) via its Perth Regional Programme Office, the Scientific Committee on Oceanic Research (SCOR), and the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER) program are preparing the celebrations for the 50th anniversary of the International Indian Ocean Expedition (IIOE), which was one of the greatest international, interdisciplinary oceanographic research efforts of all time.
The IIOE-2, as the follow-on project is known, will organize and define a science plan and implementation strategy and an international participant list for a new international, interdisciplinary research program in the Indian Ocean. Moreover, it will motivate and coordinate an integrated outreach and education component in the region aimed at, among other things, recognizing and celebrating the history of Indian Ocean research. An important challenge will be to identify key gaps in our understanding of the Indian Ocean, which will be crucial for justifying ship time for research expeditions and repeat lines in times of tight budgets and economic constraints.
The climate research community is facing a complex challenge that includes improving current knowledge on the climate system, the interactions among its components and the limits of predictability. The challenge also involves enhancing its ability to interact with other disciplines, particularly decision makers (including those who elaborate policy) and social scientists in order to translate climate knowledge into actionable information.
This year, CLIVAR has supported WCRP in the organization of two large conferences that are helping to bridge the interactions of different scientific communities. The Africa Climate Conference 2013 (ACC2013) was organized by the WCRP, the Africa Climate Policy Centre (ACPC) and the University of Dar es Salaam, and held October 15 to 18, 2013 at the Arusha International Conference Centre in Arusha, Tanzania. It discussed the state of knowledge on the African climate system, identified current gaps in climate knowledge, identified priority areas and outlined an agenda to advance the frontiers of African climate research that will inform development and adaptation decisions, drafted a road map for mainstreaming climate information into decision making, and identified key African institutions to nurture research ideas and further develop them into pan-African research program proposals that enhance climate services. The ACC2013 brought together diverse experts in climate science research, applications and policy to provide suggestions on translating climate information and knowledge to areas such as agriculture and food production, water resources management, risk management, health and adaptation planning.
In Latin America, the WCRP Conference for Latin America and the Caribbean: Developing, Linking and Applying Climate Knowledge (WRCP-LAC) will happen in 2014 and is aimed at identifying gaps and ways to overcome limitations in the chain of knowledge, going from basic to applied climate science and to informing policy and decisions that are particularly relevant for the region.
This will imply building interdisciplinary capacity and fostering the participation of decision and policy makers, climate and social scientists, and key intermediary institutions.
Moreover, it is also expected that the WCRP-LAC could contribute to the discussions on the emerging provision of regional climate services.