Vegetation-Atmosphere Interactions.
It has become increasingly evident that vegetation plays a fundamental role in the climate system. Deforestation results in changes in energy and water budgets that can influence climate at multiple scales. We have been examining these effects in the tropics, with particular attention to predicting how fire regimes are likely to respond to large-scale deforestation. More recently, we have working to improve simulations of surface processes in the Community Land Model (CLM) by incorporating a physically realistic representation of water transport through the soil-plant-continuum.
Projected decrease in mean annual precipitation due to large-scale clearing of tropical savanna, as simulated by CCM3-LSM	Projected increase in fire risk, as measured by the McArthur Forest Fire Danger Index (FFDI) due to large-scale clearing of tropical savanna.
Publications Jackson, R.B., Farley, K.A., Hoffmann, W.A., Jobbagy, E.G., McCulley, R.L. (2007) Carbon and water tradeoffs in conversions to forests and shrublands. Pp 237-246 in J. Canadell, D. Pataki, L. Pitelka (eds.) Terrestrial Ecosystems in a Changing World. Hoffmann, W.A., W. Schroeder and R.B. Jackson. 2003. Regional feedbacks among climate, fire, and tropical deforestation. Journal of Geophysical Research – Atmospheres, 108, DOI: 2003JD003494. Hoffmann, W. A., W. Schroeder, and R. B. Jackson. 2002. Positive feedbacks of fire, climate, and vegetation change and the conversion of tropical savannas. Geophysical Research Letters, 15: doi: 10.1029/2002GL015424 Dickinson, R.E., J.A. Berry, G.B. Bonan, G.J. Collatz, C.B. Field, I.Y. Fung, M. Goulden, W.A. Hoffmann, R. Jackson, R. Myneni, P. Sellers, M. Shaikh. 2002. Nitrogen controls on climate model evapotranspiration. Journal of Climate, 15:278-295. Hoffmann, W. A. and R.B. Jackson. 2000. Vegetation-climate feedbacks in the conversion of tropical savanna to grassland. Journal of Climate 13:1593-1602.