Lennart Bengtsson, a Swedish meteorologist with 50 years experience in weather forecasting, will be awarded the prestigious Alfred Wegener Medal for his notable contributions to climate modelling. Bengtsson, a former director of the Max Planck Institute for Meteorology, will present his latest findings on extratropical cyclones and their impact on this century’s climate change at the EGU 2009 in Vienna. On this occasion he will receive the prestigious Alfred Wegener Medal & Honorary Membership. This award, named after the discoverer of continental drift, is presented each year to a scientist who has achieved “exceptional international standing in atmospheric, hydrological or ocean sciences”. For Bengtsson, it crowns a long and remarkable career.

Understanding ice: Eric W. Wolff to receive Louis Agassiz Medal

For cryospheric scientists, ice is more than just frozen water. The chemical composition of accumulated snow in ice sheets contains a wealth of information about the earth's climate in the past. Ice cores show us global fluctuations in temperature and greenhouse gas concentration. Most importantly, they reveal ice ages. The study of these huge periodic swings in temperature is crucial for our understanding of the climate system. Eric Wolff, researcher at the British Antarctic Survey, has played a central role in the successful European Polar Ice Coring in Antarctica Programme (EPICA), recovering a 740,000 year long climate archive. Eric Wolff also studied physical properties of ice sheets such as electrical conductivity and mechanical strength. In his medal lecture at the EGU General Assembly, Wolff will give a comprehensive overview of the science of ice. Eric Wolff will receive the Louis Agassiz Medal at the EGU 2009.

Soil erosion: Gerard Govers to receive Ralph Alger Bagnold Medal

Soil erosion is a natural process, shaping landscapes over the course of time. However, in those parts of the world where population density is high and cultivatable land is scarce, soil erosion is a major problem. When vegetation cover on a slope is reduced, usually for growing crops or grazing livestock, soil is washed away easily during rain showers. Geomorphologists study these processes; their laboratory and field research have already produced a considerable amount of knowledge that can be used to counter this problem. Yet up until now, they haven't really made use of short-term, small-scale agriculturalists’ data. Gerard Govers, researcher at Leuven University, has found that incorporating this knowledge into long-term landscape evolution models can greatly benefit the science of geomorphology. For this, and many other significant contributions to the field of geomorphology, Govers will receive the Ralph Alger Bagnold Medal at this year's EGU General Assembly.

Grasping the geodynamo: David Gubbins to receive Arthur Holmes Medal

Since Einstein described the origin of the Earth’s magnetic field as one of the greatest unsolved problems of science, this phenomenon has been studied thoroughly by physicists and geologists. Arthur Holmes, after which this award is named, made an important contribution to so-called dynamo theory in 1944 by suggesting that convection might take place in the earth’s mantle. Indeed, convection is a critical factor in the genesis of the geodynamo, as David Gubbins will show in his EGU 2009 medal lecture in Vienna, even though it is the deeper convection in the earth’s core that defines earth magnetism. Gubbins, a research professor at Leeds University, studies the still largely unknown processes at the border of the earth’s solid inner and liquid outer core, as well as at the core-mantle boundary. Convection and heat flux between these layers are responsible for the behaviour of the magnetic field, including geomagnetic reversals. The causes behind these reversals are still a major topic of debate. At the EGU 2009, David Gubbins will receive the Arthur Holmes Medal.

Looking for life on Mars: Rafael Navarro-Gonzáles to receive Alexander von Humboldt Medal

Deserts on earth can be so inhospitable that hardly any form of life can survive there. Traces of life may be present in the soil, but they are difficult to find. Rafael Navarro-Gonzáles, a biochemist at the National Autonomous University of Mexico, studies life in such extreme environments. His most renowned research focussed on the Atacama Desert in South America, west of the Andes Mountains and one of the driest and oldest deserts in the world. Here, Navarro-Gonzáles managed to indicate the presence of organic material by conducting incubation experiments. For the search for life on Mars, this is an interesting finding as the geological circumstances in the Atacama Desert are similar to those on Mars Both NASA and ESA are now testing their new equipment there. In the autumn of 2011, the Mars Science Laboratory will be launched. Rafael Navarro-Gonzáles will be a member of the science team that will analyse the collected data. At the EGU 2009, Navarro-Gonzáles will receive the Alexander von Humboldt Medal, awarded each year to a scientist from a developing country, for his outstanding scientific achievements.

Feedbacks in climate: J. Ray Bates to receive Vilhelm Bjerknes Medal

Feedback loops are a vital feature of the climate system as they cause a change in conditions to be either amplified or weakened. The Albedo feedback, for example, increases temperature in polar regions even further when ice is melting, as the darker ground absorbs more heat as it is being exposed to the sun. Feedbacks make our climate less stable and less predictable; climatologists struggle to correctly incorporate them into their models. J. Ray Bates, an expert in mathematical issues like these, will present new results from his study on the use of feedbacks in climate modelling at the EGU 2009. A major problem, Bates argues, is the lack of internationally agreed standardised definitions. A clear distinction needs to be made between different types of feedbacks, such as the distinction between stability-altering and sensitivity-altering feedbacks. Currently employed at the University College of Dublin, Prof. Bates previously worked at NASA Goddard Space Flight Center in Maryland, USA and at the Niels Bohr Institute in Copenhagen, Denmark. At the EGU 2009, J. Ray Bates will be awarded the Vilhelm Bjerknes Medal for his distinguished achievements in atmospheric sciences.