5 research outputs found
A mobile system for quantifying the spatial variability of the surface energy balance: design and application
El Niño-La Niña cycle and recent trends in continental evaporation
The hydrological cycle is expected to intensify in response
to global warming. Yet, little unequivocal evidence of such
an acceleration has been found on a global scale. This
holds in particular for terrestrial evaporation, the crucial
return flow of water from land to atmosphere. Here we use
satellite observations to reveal that continental evaporation
has increased in northern latitudes, at rates consistent with
expectations derived from temperature trends. However, at the
global scale, the dynamics of the El Niño/Southern Oscillation
(ENSO) have dominated the multi-decadal variability. During
El Niño, limitations in terrestrial moisture supply result in
vegetation water stress and reduced evaporation in eastern
and central Australia, southern Africa and eastern South
America. The opposite situation occurs during La Niña. Our
results suggest that recent multi-year declines in global
average continental evaporation reflect transitions to El
Niño conditions, and are not the consequence of a persistent
reorganization of the terrestrial water cycle. Future changes in
continental evaporation will be determined by the response of
ENSO to changes in global radiative forcing, which still remains
highly uncertain