Date: April 15, 2015
Source: Department of Energy, Office of Science
A team applied sophisticated mathematical solutions to fine tune water and energy exchange parameters, numerical stand-ins for complex processes, to more accurately simulate water and energy fluxes in an important model under different conditions.
The exchange of water and energy between the atmosphere and land is among the most uncertain aspects of climate modeling. For example, when rain falls on land, the amount of water that evaporates back into the atmosphere or gets carried by groundwater to rivers and the ocean is unclear. The answer to this and similar questions could be estimated using climate models, but these models have numerous variables or "parameters" that must be adjusted based on observations of different regions of Earth. One way to adjust these parameters is to run the model repeatedly, each time changing the parameters individually until a solution that matches observations is found. However, it is possible that a different set of solutions would also match observations. Researchers evaluated inversion methodologies at select field sites based on global sensitivity analyses. They found significant improvements in the model simulations that better match the observed heat flux and runoff by using the estimated parameters compared to using the default parameters.Improvements in heat flux were found especially in areas with strong energy and water constraints.
