6533b82bfe1ef96bd128d330

RESEARCH PRODUCT

Interannual memory effects of vegetation in semi-arid Africa

Nadège Martiny Pierre Camberlin Yves Richard Nathalie Philippon

subject

[SDU.STU.CL] Sciences of the Universe [physics]/Earth Sciences/Climatology[SDE.MCG.CG] Environmental Sciences/Global Changes/domain_sde.mcg.cg[ SDE.MCG.CG ] Environmental Sciences/Global Changes/domain_sde.mcg.cg[ SDU.STU.CL ] Sciences of the Universe [physics]/Earth Sciences/Climatology

description

Over 15 years of Normalized Difference Vegetation Index (NDVI) data from the Advanced Very High Resolution Radiometers (AVHRR) are used to study the response of vegetation activity to rainfall in three semi-arid regions of Africa, diversified in terms of geography (Western, Southern and Eastern Africa), topography, rainfall regime and vegetation. The relationships between annual NDVI and annual precipitation (PPT) time series are examined using statistical approaches (simple and partial correlations, linear multiple regressions). It appears that annual NDVI highly depends on PPT of the concurrent year and the previous year. An analysis of particularly dry and wet years enables to better diagnose two asymetrical memory effects of vegetation. The first effect represents the difficulty of vegetation to recover from previous two-year drougth conditions. The second effect represents the capacity of semi-arid ecosystems to benefit from a water surplus at a one-year time-lag.

yearjournalcountryeditionlanguage
2006-01-01
https://hal.archives-ouvertes.fr/hal-00092463