chapter  17
20 Pages

Integration of Remote Sensing and Modeling to Understand Carbon Fluxes and Climate Interactions in Africa

ByChristopher A. Williams

African carbon dynamics are of global significance, with as much as 40% of the world’s fire emissions, about 20% of each of global net primary production, heterotrophic respiration, and land-use emissions, and acting as a major source of interannual variability in global net carbon exchange (Williams et al., 2007). Much of the continent is vulnerable to degradation from multiyear drought cycles (e.g., Nicholson, 2000), jeopardizing the livelihoods of millions who depend on local ecosystem services such as food, forage, fuel, and fiber (UNCTAD, 2002). The potential release of large amounts of carbon currently stored in African ecosystems is cause for concern (IPCC, 2001). Additionally, global environmental changes could trigger strong biophysical feedbacks to the climate system that may accelerate warming and prolong droughts (e.g., Wang and Eltahir, 2000a; Zeng and Neelin, 2000). Appraising

CONTENTS

Introduction ......................................................................................................... 327 Climate and Disturbance Controls ................................................................... 328 Analytical Framework ........................................................................................330 Geographic Variation in Emergent Limitations .............................................. 332 Teleconnections to Climate Indices ..................................................................334 Unique Patterns of Variability ...........................................................................336