The world might get unexpectedly wetter than earlier believed, a new study carried out by the California-based Remote Sensing Systems (RSS) has said.
According to the satellite-based research undertaken by Frank Wentz and his colleagues, global temperatures have risen, but precipitation has also kept pace.
The findings also cast doubt on the ability of climate models to accurately predict precipitation on regional scales.
The study and conclusions of satellite data of the previous two decades, which will appear in Saturday's issue of the journal Science, further says that this work marks the first test of the models' accuracy predicting rainfall.
The authors of the study are quoted by the National Geographic as saying that computers tend to underestimate the amounts of rain and snowfall.
They say that simulations also mask exact year-to-year changes in moisture, fail to register El Niņo events, and fail to capture precipitation trends on decade scales.
Most computer models say that as the globe heats up, "the wetter areas on the planet are going to get wetter and the drier areas are going to get drier, which is a gloomy prediction," Wentz said.
The satellite data showed slight support for that prediction, but not enough to convince the authors that it will continue to hold true.
If the models are wrong about regional effects, that could be good news for places like the U.S. Southwest, which has withered under varying degrees of drought since the turn of the century. But for other regions already prone to heavy rains, more precipitation could spell disaster.
Brian Soden, a professor at the University of Miami who was not involved with the study, said the new paper is likely to be controversial.
It suggests that "all models used to predict global warming underestimate the rate at which precipitation increases in response to surface warming. If these models turn out to underpredict the global mean precipitation response, it seems plausible that they would also underpredict the increased frequency of heavy rain events," Soden said.
Wentz believes that computer experts have to now reconcile the differences between their models and what the satellites show.