Profile

Prof Mitchell has a BSc in Physics and Astronomy and a PhD in Atmospheric Physics from The University of Sheffield and worked at The University of Wales Aberystwyth before joining The University of Bath in 2002.

He is an Honorary Researcher at the British Antarctic Survey, an emeritus professor in Electronic and Electrical Engineering at Bath, and a member and former Director of Bath’s Centre for Space, Atmospheric and Oceanic Science.

Research

Prof Mitchell researches the physical processes that are critical in coupling the different layers of the Earth’s atmosphere. Understanding the nature of these processes is essential in developing the new generation of whole-atmosphere computer Global Circulation Models models (GCMs) for climate research and numerical weather prediction. He is particularly interested in experimental work to determine the role of gravity waves, tides and planetary waves that couple the stratosphere and mesosphere to the thermosphere/ionosphere above and to the troposphere below. Measurements are made by satellites, radars and other techniques to determine the fluxes and variability of these waves and tides on time scales from as short as the day-to-day up to the decadal timescales associated with climate change and the solar cycle.

A strong focus of his recent work is studies of the winds, waves and tides of the atmosphere at latitudes near 60 S, where modern computer models suffer their most significant, long-standing and perplexing biases - collectively known as the “cold pole problem”. Prof Mitchell and his colleagues are addressing this problem by measuring the fluxes of waves generated by winds blowing over the mountains of the Southern Andes, the island of South Georgia and the Antarctic Peninsula and by sources over the open Southern Ocean. They are investigating how these waves couple the atmosphere to heights of 100 km, effectively the edge of space.

Prof Mitchell was PI on the first permanently sited meteor radars deployed in both the Arctic and Antarctic and has been PI of radars deployed on Ascension Island and on the remote, isolated mountainous island of South Georgia. The radar measurements are complemented by satellite observations made by instruments including NASA’s MLS and AIRS and the COSMIC constellation. There is strong research collaboration with The British Antarctic Survey and with leading international groups in Europe, the US, Australia and Japan.