• Environmental Physics
• Water Cycle 
• Climate Change Science
• Ecohydrology (including plant-water relations)
• Carbon-water-nutrient cycling
• Remote Sensing
• Ecological Dynamics

Changing Hydroclimates

Changes in water availability is perhaps one of the most important impacts of climate variability and climate change and has impacts on agriculture (food supply), ecology (terrestrial ecosystems) and water supply for human settlements. My research uses both historic observations and climate model simulations and projections to understand how water availability has changed, and how it might change into the future.

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Do the wet get wetter and dry get drier?

It is widely assumed that the “wet get wetter and dry get drier” but is this actually what climate models project? In a recent paper we set out to investigate this idea using the output from 23 different climate models. In terms of the difference between precipitation (P) and evaporation (E) over land we found that climate models project that the dry stay dry while the wet can getter wetter or drier depending on how P changes. We also found that climate model projections of P-E follow the empirically determined Budyko-based framework of catchment hydrology.

Drought Physics

During drought the air is usually warmer. The most common interpretation in the wider public is that the warmer causes faster evaporation leading to drying.  However, land surface scientists have long interpreted this correlation in a more or less opposite fashion. Their interpretation is that the decline in evaporation causes warming of the air. Which interpretation is correct? This had never been determined because it is very difficult to separate cause and effect using standard weather observations. We recently developed a new approach to separate the cause from the effect using radiation observations made by global satellites. Our results supported the scientific interpretation that a decline in evaporation leads to more warming during meteorological drought. Physically based findings of this sort enable a better assessment of climate variability and climate change.