1997: Peter S. Eagleson, USA

With his open mind, Eagleson is exposing the role played by natural selection in the development of the various shapes, features and functions of forests, as well as the role of climate in this process. Eagleson’s equation for a climatic water budget led him to exciting conclusions about how limitation of water in the soil can control vegetation patterns.

Professor Peter S. Eagleson, Massachusetts Institute of Technology, United States - Stockholm Water Prize 1997

What makes Professor Peter S. Eagleson special is that he is no traditional hydrologist; he is also at ease with Darwinian ecology and mathematics.

Long before he involved Darwin, Eagleson had frequently ‘disturbed’ hydrology as an established science.

He did so in 1970, for example, when he published his book Dynamic Hydrology, which provided a new, modern base for the entire discipline. Since 1952, Peter Eagleson has worked at the renowned MIT, Massachusetts Institute of Technology, in Cambridge, Boston. Since 1965, hydrologist Eagleson has been holding a chair as Professor of Civil and Environmental Engineering, a combination which hints at multidisciplinary aspirations.

For decades he has been seeking to develop new models of dynamic hydrology, looking at the hydrological cycle as the key process linking the physics, biology and chemistry of the Earth system. It was for this work, among other things, that he was rewarded with the Stockholm Water Prize in 1997.

“By working on a larger scale in hydrology, and taking into account a greater range of the complex geophysical-ecological interactions, we can do a lot better at long-term forecasting of both the availability and the hazardousness of water,” he explains.

“"We need to get away from a view of hydrology as a purely physical science. Life on earth also has to be a self-evident part of the discipline. In particular, I’m thinking of vegetation and its powerful interactive relationship with the atmosphere, at both a local and a global level. In attempting to get the full picture, we must not be afraid to express the role of plants in our mathematical equations. Until we can successfully describe the behaviour of a tree – for example, establish the relationship between productivity and environment – it will not be possible to make credible statements about changes in the climatic water balance. ”

Peter S. Eagleson

Peter Eagleson is the scientist who integrated ecology and hydrology into what Europeans often consider to be a new science, ‘ecohydrology’, and who redefined hydrology from an ad hoc engineering speciality to a multidisciplinary, global environmental geoscience, in which the green, living features of the ecosystems have an important part to play.

Professor Peter S. Eagleson at the MIT created a new platform for longer-term and more credible forecasts, be it of weather, water availability, or threats from water and potential floods. And he dared to bring different disciplines together, for example by integrating hydrological processes into mathematical computer models for large-scale climate forecasts.

Since 1997, Professor Eagleson has continued his exploration of the Darwinian connections between vegetation and climate; the practical goal being to anticipate, temporally and spatially, the biological changes that climate change will bring. His book, Ecohydrology: Darwinian Expression of Vegetation Form and Function, containing early results was published in 2002. The book bridges the fields of hydrology and ecology and proposes new unifying principles derived from the concept of natural selection. It also has potential application in determining the response of vegetation to slow variations in climate. He is now writing a second book dealing with the geographical range and diversity of tree species.