Climate change is intensifying the water cycle at twice the rate expected, as it is now showing

The water cycle on our planet is becoming increasingly intense. Global temperature rise According to new analysis It diverted at least twice as much fresh water from warm regions to Earth’s poles than previously thought. What that means is that we’re seeing stronger and more frequent droughts and more torrential rain than the models predicted.

The water cycle describes all the processes in which water circulates through the Earth’s system. Surface water, such as seawater, evaporates during this process. In the atmosphere, this vapor forms clouds from which precipitation falls. This returns to land in waterways, or sinks as groundwater. A large portion collects again as surface water.

Climate change has intensified the global water cycle by 7.4% – compared to previous model estimates of 2 to 4%. The water cycle has traditionally been viewed as an unchanging process that constantly replenishes our water resources. But scientists have long known that rising global temperatures are intensifying the global water cycle, which means arid subtropics are likely to become drier as fresh water flows into wetter regions.

Stronger and more frequent droughts and heavy rains

Last August, the Sixth Assessment Report of the Intergovernmental Panel on Climate Change concluded that climate change will lead to long-term changes in the water cycle, leading to stronger and more frequent droughts and heavier rainfall.

Scientists estimate that the amount of additional fresh water that moved from warmer regions between 1970 and 2014 ranges from 46,000 to 77,000 cubic kilometres. This is a higher intensification of the water cycle than expected.

The team used ocean salinity as a way to measure precipitation in their study. The ocean is saltier in some places and less salty in others. When rain falls into the ocean, it tends to soften the water, making it less salty. When there is more evaporation, more salt is left at the end. The researchers had to take into account the mixing of the waters with ocean currents.

All data show that current climate modeling has underestimated the potential effects of climate change on the water cycle.

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