CLIVAR 2004 Session Descriptions

1. Short term climate prediction

This session will consider climate variability and predictability on time-scales from months to a few years including processes, elements, and modes of the climate system, which affect variability and predictability on these time scales. A particular aspect will be to review progress in ENSO prediction, as well as other seasonal-to-interannual variability/predictability, and results of extended prediction in general.

2. The monsoon systems

This session will consider the different monsoon circulation systems, their role in the Earth’s climate, the physical mechanisms behind them, and progress in their predictability. This will include monsoon variability, intensity, duration and occasional breaks in the monsoon. The response of the monsoon circulation systems to anthropogenic forcing may also covered.

3. The challenge of decadal prediction

The causes of decadal to centennial modes of the climate system as observed during the 20th century were initially identified as key objectives of CLIVAR. This is still the case and this session will address these modes, e.g. PDO, NAO, and annular hemispheric modes. This includes for example the long–term variations in the Asian monsoon, in Sahel rainfall, in water storage in lakes, such as the Caspian Sea, and extremes of Arctic temperatures, such as the warming event 1930-1940. A fundamental challenge to CLIVAR and the essence of this session is to determine sources of predictability and in what degree such fluctuations are predictable.

4. Understanding long-term climate variations

This session will consider climate variations on very long time scales covering in principle the whole Holocene but with emphasis of the last few thousand years. Climate reconstruction based on paleodata, model experiments as well as specific model studies to interpret the paleodata will be considered in this session.

5. The role of oceans in climate

Ocean processes are essential for longer-term climate variations. It is expected that the contributions in this session in difference to other sessions, will be to better identify the role of specific oceans on climate but with the emphasis more on specific processes. There is no specific time scale in mind but the emphasis is expected to be on decadal and longer time scales. Additionally, this session will address the potential role of the ocean in abrupt climate change, the role of ecosystems on the ocean-atmosphere system, and sea level change.

6. Human influence on climate

This session will review progress in our understanding of human influences on climate. It will consider the role of greenhouse gases (including ozone), atmospheric aerosols and anthropogenic changes in land surface condition on climate trends and variability. Not only are these forcings to be considered, but also the feedbacks (including that from the ocean) to the climate system. Contributions on detection of climate changes and variability of climate extremes (e.g. droughts, hurricanes) are also encouraged.

7. Application of CLIVAR science to society

It is expected that there will be two kind of contribution here. First, we welcome contributions describing examples and methodologies of how climate information, such as predictions on shorter climate time scales, supports society in areas of health, water, energy, agriculture and fisheries/ecosystems. How is climate information being explored in the general information expert systems in these fields? How can ensemble prediction systems be applied? Secondly, how can climate simulations best be applied and interpreted for different applications? How shall for example ensemble predictions best be composed in order to better estimate risks of extreme climate events?

8. CLIVAR - future challenges

It is expected that the outcome of the conference will contribute to the formulation of the future CLIVAR program including setting priorities for CLIVAR and to identify new areas of research following the progress in observational technology and advanced modeling (development and application). This is likely to include more advanced systems to assimilate ocean, land and atmospheric data and introduction of more advanced climate models making use for example non-hydrostatic equations at higher resolution. Descriptions of new approaches that link process-oriented and observation-based research to better climate models, assimilation, and prediction systems are also encouraged.