| Citation | For his contribution as a world leader in the understanding and prediction of climate change. Through individual contribution and leadership of his research group he has developed complex numerical models of climate research. He has led the way in quantifying the uncertainties in predictions, in particular being first to quantify uncertainties in cloud-climate feedbacks. His work has led to substantial advances in the prediction and detection of climate change; he was the first to show sulphate aerosols could explain much of the discrepancy between simulations and observations of recent climate. With colleagues, he first showed the potential complexity of the Atlantic thermohaline circulation response to increases in greenhouse gases. He is one of the pioneers of model simulation of past climates. He has made major contributions to the assessments of the Intergovernmental Panel on Climate Change and exerts a strong influence on the development of his field through collaboration and membership of international bodies. |