Study finds wet areas of world getting wetter, dry areas more parched

Researchers deployed 3,500 robotic buoys around world's oceans to collect data (Image: CSIRO: Alicia Navidad)
Researchers deployed 3,500 robotic buoys around world's oceans to collect data (Image: CSIRO: Alicia Navidad)

New Orleans and other relatively wet areas of the world could be in for more rainfall in coming decades while drier regions become more parched, if the findings of a new study prove accurate.

Scientists say they have measured changes in salinity of the world's oceans and in the water cycle that drives rainfall and evaporation.

The findings published on Friday helps refine estimates of how different parts of the globe will be affected by increased rainfall or more intense droughts as the planet heats up, affecting crops, water supplies, and flood defenses.

The researchers, led by Australia oceanographer Paul Durack of the Lawrence Livermore National Laboratory, reported clear changes in salinity patterns across the world's oceans between 1950 and 2000.

Oceans cover 71 percent of the planet's surface and store 97 percent of the world's water and are therefore the main source of moisture in the atmosphere through evaporation.

Warmer air allows for more water vapor, leading scientists to predict a more intense pattern of evaporation and rainfall.

"What we found is that regions that are salty in the main are becoming saltier," Durack said.

Durack and his colleagues from Australia looked at ocean salinity measurements from roughly 3,500 robot buoys—collectively known as Argo—that have been deployed since 2000.

The stronger water cycle will mean stronger rains and intensified droughts over the oceans, Durack's team predicts.

The results of the study are detailed in a number of publications, including Scientific American.