Centre Project: Weather Systems in a Warmer World

As the Earth warms, the circulation of the oceans and atmosphere will change, and so will the weather systems they interact with. These weather systems include low-pressure systems (like cyclones) and high-pressure systems (anticyclones), which often produce stable and dry conditions.

The exact nature of weather system change will be determined by a complex interaction of thermodynamic factors (the interplay of heat, temperature and energy), changes in surface conditions, and changes in the major modes of climate variability (such as the El Niño-Southern Oscillation, or ‘ENSO’).

All three of these factors are themselves strongly affected by weather systems, creating a complex system with unpredictable feedbacks.

This project will consider the relationship between weather systems and global warming to identify the mechanisms that underpin weather system change, providing a foundation for better estimates of their future behaviour.

Knowledge Gaps

We know that the rise of global mean temperature and more water vapour in the atmosphere can change planetary circulation. But we need to better understand how these thermodynamic changes and modified atmospheric circulation affect weather systems and lead to weather change near the Earth’s surface. Targeted numerical experiments and high-resolution computer models will be used to tackle this challenge.

Benefits

Climate change is warming the Earth’s surface in different ways in different places. For example, there is uncertainty over how sea surface temperatures in the tropical Pacific region will change, which can determine how wet or dry Australia will be in the future. Given their large effect on Australian weather, being able to anticipate changes in the frequency and intensity of the major modes of climate variability affecting Australia, such as ENSO and the Indian Ocean Dipole (IOD), is vital to predicting weather change.

In conjunction with the Climate Variability and Weather Systems projects, we will improve our understanding of how the ocean, atmosphere and land interact, to develop better information about change and variability of sea surface temperatures. We will also learn more about how  changes in surface warming patterns influence where future weather systems are likely to occur and how they will manifest.

Ultimately, this project will enable us to know more about the future of the Australian monsoon, tropical cyclones, and tropical climate variability, to develop a clearer picture of Australia’s weather patterns, weather resources and hazards.

Goals & Objectives

• Identify and quantify the mechanisms by which thermodynamic climate changes interact with weather systems;
• Identify the processes that connect changes in climate variability with weather-regime characteristics as the Earth warms;
• Assess the ability of climate models to simulate the mechanisms involved in weather system change.