Social and Behavioral Sciences Commons^™

Interannual Variability Of Photosynthesis Across Africa And Its Attribution, Christopher A. Williams, Niall P. Hanan, Ian Baker, G. James Collatz, Joseph Berry, A. Scott Denning

Geography

Africa is thought to be a large source of interannual variability in the global carbon cycle, only vaguely attributed to climate fluctuations. This study uses a biophysical model, Simple Biosphere, to examine in detail what specific factors, physiological (acute stress from low soil water, temperature, or low humidity) and biophysical (low vegetation radiation use), are responsible for spatiotemporal patterns of photosynthesis across the African continent during the period 1982-2003. Acute soil water stress emerges as the primary factor driving interannual variability of photosynthesis for most of Africa. Southern savannas and woodlands are a particular hot spot of interannual variability in …