2014 Dirac medal

Professor Tim Palmer, University of Oxford. For the development of probabilistic weather and climate prediction systems.


During the last three decades, Palmer has led in a revolution in the fields of weather and climate by establishing a physical basis for understanding nonlinear error growth in prediction models and for developing practical ways of estimating flow-dependent predictability. He has challenged old ideas and has changed the way that weather and climate are viewed both by the public, by associates in the same field, and by scientists in other disciplines.

Palmer’s work in weather and climate predictions is a beautiful blend of theoretical insight and practicality. Based on his insights into chaotic behaviour of fluids, he has created a system that gives the wealthy and the poorest of the poor throughout the world a determination of the probability of drought, flood, tropical cyclones or hydro-meteorological hazards in general. This probability has allowed them to determine their levels of risk and, if worthwhile, allows them to instigate mitigation. For example, Palmer’s probabilistic predictions have been used in Bangladesh where, for the first time, societies can anticipate slow-rise, long-lived floods. The savings for the mitigating actions in Bangladesh are of the order of annual incomes.

Normally, the societal benefits of ideas take a long time to permeate to the practical level. But Palmer, having practical applications in mind, has formed an almost immediate link between his theoretical insights and practical applications.