Research program: The effects of tropical convection on Australia's climate

Convection is the atmospheric phenomenon that leads to upward and downward air motions, producing most clouds and rain. It can be shallow and produce little rain, or reach all the way to the lower stratosphere and produce heavy rains, as well as thunder and lightning. Deep convection in the Tropics can be triggered by very subtle influences, and drives atmospheric wind systems that can affect the weather or climate thousands of kilometres away. Convective processes are also often critical in extreme weather events, such as tropical cyclones and hail storms.

While the processes of convection are broadly understood there remain significant gaps in our knowledge. These gaps have made it impossible for weather and climate models to provide reliable predictions of precipitation, particularly where convection is a dominant process.

The Centre will conduct a fundamental re-examination of convection processes that when completed should substantially improve the physical foundation of climate models. This has the potential to lead to significant improvements in the ability of climate models to reliably simulate rainfall over key regions in Australia over a variety of time scales.

This will help us predict changes to precipitation in important regions and put in place infrastructure to adapt to changes in the frequency and intensity of extreme rainfall events.

Convective Parameterization Development

A long-term goal motivating our research is the development of a new convective scheme for atmospheric models. Work toward this is just getting underway--see these publications.

Modeling and Dynamics of Tropical Convection

Our primary tool for better understanding atmospheric convection is the use of numerical models that explicitly simulate the phenomenon in realistic settings. We are using these models to explore the role of sea breezes and other triggers of convection, quantify transports of energy and momentum, and examine the dynamics of individual air parcels in a convective environment.

Observations of Tropical Convection

Observations of convection are also crucial, especially from radars and satellites. Much of our work observing convection is in conjunction with CAWCR, our most closely involved Partner Institution.

Role of Convection in Climate

Last but not least, we are exploring the roles played by convection in regulating the character of variations in climate, both natural and resulting from external influences.