The climate system is an interactive system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the land surface and the biosphere, forced or influenced by various external forcing mechanisms such as solar variability, volcano eruption, and human activities. In the presentation, several examples (global warming, El Nino, global thermalhaline circulation, and India Summer Monsoon) are given to show the complexity of physical processes in the system. Then I will introduce the history of numerical weather prediction and the research activities in our laboratory.
Numerical weather prediction forms the basis of most of modern weather forecasting services since 1950s. Atmospheric models have proceeded from predicting large-scale systems to resolving mesoscale systems. Models have been much improved for predicting mean variables like pressure, temperature and moisture, but it is still poor in predicting rainfall. There are a number of technical difficulties to be solved: steep orogaphy, polar singularity, model initialization, sub-grid scale processes (I am not familiar with the topic, please don’t expect too much).
Studies on the climate have to talk two aspects: energy cycle (e.g. global warming) and water cycle (e.g. water resources availability and variability). Basically, we understand global water and energy cycles much better than regional ones. Because there are numerous processes that have not been fully understood, model uncertainties are still quite large. The GEWEX (global water and energy cycle experiments) is initiated to implement continental scale experiments and international model intercomparisons to investigate these physical processes and model uncertainties. Our laboratory is being involved in GAME (GEWEX Asia monsoon experiments) and is initiating the international project of CEOP (Coordinated Enhanced Observing Period). In the presentation, our work in these fields and some relevant topics will be addressed.