Multiscale Processes in the Tropics (09w5073)


Boualem Khouider (University of Victoria)

(New York University)

(Canadian Centre for Climate Modelling and Analysis)

Adam Monahan (University of Victoria)


The Banff International Research Station will host the "Multiscale Processes in the Tropics” workshop next week, April 26 - May 1, 2009.

The tropical climate is characterized by dramatic variability affecting billions of lives, with sudden storms bringing heavy rainfall and floods or extended droughts resulting in crop failure. Unlike the mid-latitude regions, the large-scale organisation of irregular tropical weather was a mystery, and tropical weather events were believed to be unpredictable. Recent developments have significantly improved our understanding of tropical atmosphere dynamics and the associated rainfall variability. It is now recognized in the scientific community that tropical climate is organized into a hierarchy of almost-periodic oscillations occurring on different time scales (from days through months to years), and embedded one in the other. On longer timescales lies the celebrated El Nino phenomenon, which repeats on timescales of 3-5 years. The dominant atmospheric signal is known as the Madden-Julian oscillation (MJO, in honour of its discoverers) with a period of 40-50 days. The MJO is characterized by a local rainfall increase and changes in wind strength and directions, as it propagates over Indonesia and across much of the Pacific Ocean. Moreover, it is now well established that the MJO affects the monsoon seasons as well as the mid-latitude weather and climate. In particular, severe floods in British Columbia have been associated with individual MJO events. However, because of its complex nature, the inherent physics of the MJO are still not very well understood and today's climate models are unable to predict it adequately.

University-based mathematicians and physicists together with scientists from operational climate modelling centres will be gathered in the Banff International Research Station to discuss "Multiscale Processes in the Tropics." New theoretical and observational results in tropical meteorology, with a particular emphasis on the MJO and other features of organised tropical convection, and bringing to bear on the problem modern techniques of applied mathematics such as asymptotic analysis, stochastic and statistical physics, and numerical modeling.

The Banff International Research Station for Mathematical Innovation and Discovery (BIRS) is a collaborative Canada-US-Mexico venture that provides an environment for creative interaction as well as the exchange of ideas, knowledge, and methods within the Mathematical Sciences, with related disciplines and with industry. The research station is located at The Banff Centre in Alberta and is supported by Canada's Natural Science and Engineering Research Council (NSERC), the US National Science Foundation (NSF), Alberta's Advanced Education and Technology, and Mexico's Consejo Nacional de Ciencia y Tecnologí­a (CONACYT).