|Scheme:||Royal Society Research Professorship|
|Dates:||Oct 2009 - Sep 2014|
University of Exeter
My research area is the carbon cycle and its interactions with climate, particularly sources and sinks of atmospheric CO2 and how it they are changing as we emit more carbon dioxide to the atmosphere. I'm also interested in what caused atmospheric CO2 to vary naturally in the past, both relatively recently (the last million years or so, where we know from ice cores how CO2 varied) and much further back in time. We know less about the variations as we go back in time, but hypothesise that atmospheric CO2 is one of the most important variables controlling past climate variations. Humans release close to 10 billion tons of carbon into the atmosphere annually, about half of which is taken up by vegetation on land and by absorption into the ocean. These natural "sinks" are very important for us, because they slow the build-up of CO2 in the atmosphere and the rate of climate change. However, it is difficult to measure accurately how much is going into a given region of land or ocean. Though we know that the natural sinks are variable from year to year, we don't know precisely why, or how they may change in the future. My research encompasses observational studies, especially in the oceans, of the uptake and release of CO2 to the atmosphere and experiments to investigate the processes responsible for it, be they physical, chemical or biological. We also perform modelling of the Earth system, aimed at synthesising our knowledge of both the modern and ancient carbon cycles. Both this year and last year, I spent several months at sea in the Southern Ocean, as part of a major experiment that we have initiated into the mixing and circulation that controls the "overturning circulation", which determines how surface water enters the deep sea and which is thought to be critical to the carbon cycle.