Physics is key to understanding and predicting our changing climate, one of the most pressing challenges facing the world today. Research carried out within the Atmospheric, Oceanic and Planetary Physics sub-department focuses on the physical processes in the Earth’s climate system, spanning the atmosphere, oceans and cryosphere. We combine observations of the Earth’s climate system with theoretical ideas and computational models. We seek to understand how the climate system works today and how this could change in the future.

We collaborate widely with the international community and with industry.  Our academics have taken leading roles in producing the Intergovernmental Panel on Climate Change’s Assessment Reports. As a Met Office Academic Partner, we work closely with the Met Office to strengthen the physical understanding that underpins weather and climate prediction.

From extreme weather to climate change

Our research interests span from the weather tomorrow to the climate next century.

Our research covers phenomena such as the jet streams and storm tracks (Tim Woollings and the Climate Dynamics group), which are key to understanding the weather we experience in the UK. We probe how predictable are these and other weather phenomena, and how we can accurately estimate uncertainty in our forecasts on a range of timescales (Tim Palmer and the Predictability of Weather and Climate group).

For example, seasonal forecasts sit at the intersection of weather and climate (Antje Weisheimer and the Predictability of Weather and Climate group). We seek to understand what processes in the Earth System can provide us with information on these longer timescales. One possible source of skill is the stratosphere. Moreover, the stratosphere displays a range of intriguing dynamical properties which we seek to understand using theoretical ideas and large climate models (Lesley Gray, Scott Osprey  and the Climate Dynamics group).

Throughout these themes, our research seeks to understand and quantify the changing dynamics of our atmosphere due to anthropogenic climate change.

From the microscopic to the global

We study processes happening on the micrometre scale up to the global scale.

We are actively involved in observing the atmosphere using satellite instruments. We use these measurements to monitor the global state of the atmosphere (Anu Dudhia and the Earth Observation Data Group) and to detect the presence of trace gases and tiny particles, such as volcanic ash and gases, and aerosols, which are solid or liquid particles suspended in the air (Don Grainger and the Earth Observation Data Group).

As well as being a type of pollution, aerosols have a key role in cloud physics. Our research seeks to understand the myriad of interactions between aerosols and clouds, and to quantify the role that these interactions for climate change (Philip Stier and the Climate Processes group). Through better understanding of the interactions between small scale processes and the larger climate system, we can improve the computer simulators that we use to make predictions, refining our estimates of future climate change (Hannah Christensen and the Atmospheric Processes group).

On the local scale, we maintain a weather station on the roof of our building, providing real-time measurements of the weather over the Department of Physics.

From theoretical ideas to practical applications

We investigate fundamental theoretical questions related to climate physics, and pull our theoretical ideas through to practical applications. We use laboratory experiments on rotating, stratified fluids to study geophysical fluid dynamics (Peter Read and the Geophysical and Astrophysical Fluid Dynamics group). We then use ideas from fluid dynamics to understand the evolution of the Earth System. For example, our research combines theory with realistic models to probe how and why the ocean circulates, and how this might change in the future (David Marshall and the Physical Oceanography group). We apply fluid dynamics and thermodynamics to understand the physical interactions of sea ice, glacial ice sheets and the ocean, and resulting feedbacks on climate and sea level change (Andrew Wells and the Ice and Fluid Dynamics group).

Our research led to the proposed idea of a ‘carbon budget’, namely that it is cumulative emissions of carbon dioxide that determines the level of global warming (Myles Allen  and the Climate Dynamics group). This idea has transformed policy debates around global carbon emissions. We develop idealised mathematical models to understand fundamental questions in planetary climate, such as the runaway greenhouse effect, and termination of ‘snowball Earth’ climate state (Ray Pierrehumbert and the Planetary Climate Dynamics group), applicable to both the Earth’s climate and to the atmospheres of other planets (see Planetary Physics).