Any discussion of the impact of climate change will quickly identify water availability as a key for both societies and for nature. As well as considering the impact on the water cycle, we also recognise that water cycle is itself intrinsically linked with the global energy balance by evaporation. For example, the water that sustains rainfall is ultimately the water evaporated from oceans and land. Hence, in the context of climate change one can consider impacts on the water cycle, but a broader view of the topic emphasises inter-connectedness of the water cycle with the global energy balance.
Much of the traditional knowledge of the water cycle has been gained by integrating point measurements of rainfall with point estimates of evaporation and catchment estimates of streamflow. However, in the last decade, the Hydrology discipline has been developing a new approach stimulated by the ever-growing availability of satellite measurements. The satellite database toolbox now includes observations, of, for example, (i) rainfall, (ii) the total change in water mass as observed by the GRACE satellites, and a new series global radiation databases (called CERES) developed at NASA. These core hydrologic databases are complemented by satellite observations of vegetation cover and salinity observations that can be used to infer the balance between rainfall and evaporation over the ocean.
For the first time in history we now have more data than we have theory.
A number of suitable projects are available for students at different levels (e.g. undergraduate projects, Hons, MSc, PhD).
Contact: Prof. Michael L. Roderick, GFD Group