Global warming driving shift in water cycle: Australian study

CANBERRA, Jan. 12 (Xinhua) -- An Australian report has warned that global warming is changing the global water cycle.

The Global Water Monitor Consortium, led by the Australian National University (ANU), on Thursday released its first report, warning that flash droughts will become more common in the short-term future.

According to the report, the water cycle in 2022 was dominated by warmer-than-average ocean waters in the western Pacific and eastern and northern Indian Ocean, driving severe heat waves in South Asia and a severe monsoon that caused flooding in Pakistan.

In Europe and China, it said heat waves caused droughts to develop rapidly while a third consecutive La Ni a event caused catastrophic flooding in Australia but exacerbated droughts in North and South America.

Overall air temperature over land followed the long-term warming trend in 2022 while humidity declined.

"This means that nature, crops and people will need more water to stay healthy, which compounds the problem," Albert van Dijk, lead author of the report from the Centre for Water and Landscape Dynamics at ANU's Fenner School of Environment and Society, said in a media release.

"It is a safe prediction that we will see more and more of these heatwaves and flash droughts. We also see evidence of the impact of global warming on glaciers and the water cycle in cold regions, and in fact melting glaciers contributed to the Pakistan floods. That will continue until those glaciers are gone."

The first-of-its-kind report was compiled using water measurements made at thousands of ground stations and by satellites.

It forecast that dry conditions would intensify droughts in the Americas, Asia and the Horn of Africa in 2023 but said unwinding La Ni a conditions could offer some respite.

Van Dijk said it was too early to tell if the three consecutive La Ni a years were a coincidence or an indication of a trend.

"If La Ni a or El Ni o patterns are going to stay around longer in future, that is going to cause a lot of trouble, with worse, longer droughts and worse floods alike," he said.