Monitoring seasonal and interannual variations of gross primary productivity, net primary productivity and net ecosystem productivity using a diagnostic model and remotely-sensed data

Abstract

A NPP model is coupled to a soil respiration model, calibrated in order to balance the resulting net ecosystem productivity (NEP) over a year. The model seems to be able to simulate the effects of events such as El Nino on the terrestrial net primary poductivity. The NEP outputs are compared to CO2 concentration measurements in the atmosphere and seasonal evolution of NEP and atmospheric CO2 are well in phase in latitudes of the temperate Northern Hemisphere, but the correspondence is weaker or absent in the tropics and Southern Hemisphere. -from Authors