Water cycle accelerating

Researchers at the Institut de Ciencies del Mar in Barcelona have discovered that global warming is accelerating the water cycle, which could have serious consequences on the global climate system. 

This acceleration of the water cycle is caused by an increase in the evaporation of water from the oceans resulting from the rise in temperature. As a result, more water is circulating in the atmosphere in the form of vapor, 90% of which will eventually precipitate back into the sea, while the remaining 10% will precipitate over the land. 

“The acceleration of the water cycle has implications both at the ocean and on the continent, where storms could become increasingly intense. This higher amount of water circulating in the atmosphere could also explain the increase in rainfall that is being detected in some polar areas, where the fact that it is raining instead of snowing is speeding up the melting,” says Estrella Olmedo, the lead author of the study. 

The study also shows that the decrease in the wind in some areas of the ocean, which favors stratification of the water column, i.e. water not mixing in the vertical direction, could also be contributing to the acceleration of the water cycle. 

“Where the wind is no longer so strong, the surface water warms up, but does not exchange heat with the water below, allowing the surface to become more saline than the lower layers and enabling the effect of evaporation to be observed with satellite measurements,” says Antonio Turiel, another author of the study. In this sense, Turiel adds that “this tells us that the atmosphere and the ocean interact in a stronger way than we imagined, with important consequences for the continental and polar areas.”

To perform the study, researchers analyzed ocean surface salinity data—which is measured by satellites. Unlike subsurface salinity data—obtained with in situ instruments—the satellite data allowed them to detect this acceleration of the water cycle and, for the first time, the effect of stratification over very large areas of the ocean.

https://phys.org/news/2022-04-global-relevant-climatic-consequences.html