- Navin Singh Khadka
- Environment correspondent at BBC International
image source,AFP
“Sudden droughts” are more common than droughts caused by prolonged periods of lack of rainfall.
Scientists generally point out that the world is experiencing its most widespread drought in decades, with weather records set in some places. Sudden “sudden droughts” are also becoming more common.
“This year has been a lot of drought in the northern hemisphere,” said Benjamin Cook, a senior scientist at NASA (NASA) who specializes in droughts. “North America, Europe, the Mediterranean and China have suffered simultaneously. Near-record or even record-breaking heat and drought impacts.”
But experts say East Africa, South America, parts of Asia and parts of Australia are also badly affected.
One of the hardest hit areas is the Horn of Africa (Northeast Africa). The lack of water for four consecutive monsoons has prompted Nuur Mohamud Sheekh, a spokesman for a regional trade association (IGAD; an intergovernmental development organization), to call it “the worst drought in 40 years”. This, he said, would pose a food security risk to an estimated 50 million people.
According to a report by the secretariat of the United Nations Convention to Combat Desertification (UNCCD), Africa suffers from more droughts than any other continent. Of the 134 droughts that occurred between 2000 and 2019, 70 occurred in East Africa, the report said.
China also issued a nationwide drought warning this year, with persistent high temperatures drying up rivers, including parts of the Yangtze River, the world‘s third longest river.
Climate scientists have warned that extreme weather such as droughts, heat waves and forest fires are becoming more common.
image source,Reuters
Parts of the Yangtze River in China are severely dry, and the meteorological department will issue a drought warning.
The hydropower generation in Sichuan Province has dropped significantly, resulting in power cuts and suspension of navigation in some waterways. Chinese government officials said more than 2 million hectares of farmland in six provinces and municipalities were affected.
According to the European Union’s Copernicus Atmosphere Monitoring Service, the record low rainfall in western Europe has been refreshed, and the severe drought experienced by Central Asian countries such as Afghanistan and Iran has so far lasted for more than a year.
In the southern hemisphere, South America has also been affected by drought in recent years.
A UN report said the drought will reduce the global cereal harvest by 3% in 2020-2021, and central Chile is experiencing a 13-year “megadrought” – the region’s once-in-a-millennium drought.
“Additionally, the multi-year drought in the Parana-La Plata Basin was the worst since 1944, affecting south-central Brazil and parts of Paraguay and Bolivia,” the report added.
Is “sudden drought” normalized?
Severe drought in China, Poyang lake bed turned into grassland
In the past, typical droughts took several consecutive seasons or even years to develop, but scientists say the pattern has changed in many places.
The combination of low rainfall and extreme heat has created an instant drought, a phenomenon seen in parts of the northern hemisphere this summer.
“What we’re seeing right now is what’s called a sudden drought,” said Roger Pulwarty, a senior scientist at the US National Oceanic and Atmospheric Administration.
“It may only last one to three months, but if it happens during the peak crop season, or when there is a high risk of bushfires, it can cause a lot of damage.”
image source,AFP
Some parts of Africa have been suffering from prolonged drought.
He pointed out that places prone to “sudden drought” include Brazil, the Sahel region of northern Africa, the Great Rift Valley of East Africa, India, the central United States, southwestern Russia and northeastern China.
With four months to go until the end of the year, scientists say it’s too early to say whether the drought in 2022 will be worse than in 2012 – seen as the worst drought in contemporary history.
Weather records from the 20th century are also not perfect enough to rank any year in the Long-Term Drought League, but scientists told me this year’s drought was the most extensive in decades.
image source,AFP
In March 2022, the total water volume of Peñuelas Lake, an important water storage area in central Chile, shrank to only 0.2% of its original maximum.
When it comes to the future, the scientists’ words are not encouraging.
Scientists have long stated that global warming will increase the risk of droughts in some vulnerable regions, due to reduced rainfall and reduced air and soil moisture, and they expect droughts to become more severe and more frequent.
According to the “Drought in Numbers” report published by the UNCCD secretariat earlier this year, if global temperatures are to rise by 3 degrees Celsius by 2100 compared to today – as predicted, if current greenhouse gas emissions are not significantly reduced The economic costs of crop failure and other droughts would be five times higher than they are today.
“Regardless of how climate change is affecting these droughts (this year), we must prepare for these events as we move toward a warming future,” said NASA scientist Benjamin Cook.