Summary: How robust are observed and simulated precipitation
responses to tropical ocean warming?
Viju O. John,1
Richard P. Allan,2
and Brian J. Soden3
Received 22 March 2009; revised 6 May 2009; accepted 27 May 2009; published 17 July 2009.
 Robust responses and links between the tropical energy
and water cycles are investigated using multiple datasets and
climate models over the period 19792006. Atmospheric
moisture and net radiative cooling provide powerful
constraints upon future changes in precipitation. While
moisture amount is robustly linked with surface
temperature, the response of atmospheric net radiative
cooling, derived from satellite data, is less coherent.
Precipitation trends and relationships with surface
temperature are highly sensitive to the data product and the
time-period considered. Data from the Special Sensor
Microwave Imager (SSM/I) produces the strongest trends
in precipitation and response to warming of all the datasets
considered. The tendency for moist regions to become