Three massive sandstorms hit China in five weeks. Here’s how climate change is worsening their impacts on humans and the environment.
We’re bringing you exclusive content from our newsletter, The Forecast, right here on Medium. Sign up for our newsletter here. This story is from our feature called the Weather Corner, where we take a deep dive into weird weather around the world, from our May 6th, 2021, newsletter.
View of Beijing, March 17. Source: Felton Davis via Flickr.
Almost every spring, Chinese and Mongolian cities are pelted by sand and dust as particles originating in the Gobi Desert are swept into more residential urban areas across the region by high winds.
This year has been no exception: the worst dust storm in a decade hit mid-March and grounded flights, closed schools, and shrouded the air in cities of hundreds of millions of residents in an apocalyptic grey-yellow haze across much of East Asia, according to the New York Times. At least 10 people died in Mongolia, and hundreds of herders went missing searching for their cattle. At least two more sandstorms have hit since then. Beijing’s air quality index, which measures the level of pollutants in the air and last year averaged around 80, saw readings at 999 during the March 15 storm, according to NPR (anything over 300 is characterized as “hazardous” and a “health warning of emergency conditions”). In the April 15 storm, some parts of the city saw readings of 1,300, according to Reuters.
Experts point to a confluence of factors, including climate change, as the reason this year’s storms have been so strong, frequent, and dangerous.
Here’s how it happened: In early March, winds of up to 45 mph during a late winter storm in Mongolia were enough to start up these deadly sandstorms. The storm came at the tail end of a winter with climate change’s fingerprints all over it. There was lower-than-average winter snow cover and precipitation — meaning lower moisture levels in the soil, so the top layer isn’t held down as well — as well as higher-than-normal temperatures and winds across Mongolia and northern China. (Mongolia has warmed at three times the global average rate over the past 70 years.) The winds carried tiny sand and dust particles from northern China to eastern China and even to South Korea. More storms hit at the end of March and mid-April.
The path of the March 15 sandstorm. Credit: NASA
For context: Sandstorms are a naturally occurring weather phenomena. They occur when winds are strong enough to lift small grains of sand off the ground and carry them through the air — this can occur with winds as low as 25 mph, so not even hurricane-force winds (a Category 1 hurricane’s wind speed is 74–95 mph). Still, the faster the wind blows and the more sand around, the higher and farther the particles can be blown.
The Gobi Desert, which straddles the China-Mongolia border, has always had regular dangerous dust storms, but scientists have linked the severity of recent ones to human activities and climate changes. Intensified droughts and higher temperatures, which are impacts of climate change, dry out land. Urban development, mining, farming, and grazing kick up dust in previously untouched arid regions. Plus, these processes destroy ground vegetation that previously held soil in place, making the land vulnerable to wind erosion.
China has tried to pursue adaptation and mitigation solutions to these sandstorms for over 40 years. It initiated a massive infrastructure project more than 40 years ago called Three-North Shelter Forest Program, when it began planting a series of forest strips through its northern areas around the Gobi Desert in 1978, in an attempt to prevent the desert’s surrounding grasslands from degrading and becoming desert. Also known as “Great Green Wall,” it has been somewhat effective at reducing erosion and slowing desert expansion, but is unable to block against dust that’s being carried on winds at such high altitudes.
Climate change-exacerbated extreme weather events like these sandstorms have largely negative impacts on human and economic health, though they impact both urban and rural areas differently. For people in the midst of these storms, exposure to their horrifying air quality levels can make people sick. Particles less than 10 micrometers in diameter — which these storms carried across the continent — can get deep into people’s lungs and even get into their bloodstreams.
These particles might be invisible on their own, but they come together to create the most striking visuals from these storms: the disorienting orange-y haze that shrouded Chinese cities. Some of them, like Beijing, are already notorious for their poor air quality and greyish smog, with some calling the situation the “airpocalypse.” (Mid-pandemic, its air pollution levels dropped, but now, they’re rising again, thanks to increased industrial activity in post-lockdown rebounds.)
Smog in Beijing in 2014. Source: Lei Han via Flickr
“The (air) quality is much worse than in previous years,” Gary Zi, a 48-year-old Beijing resident working in finance, told The Guardian. “Breathing becomes difficult. Sand gets into your eyes and your nose.”
Sand and dust storms also affect agriculture in rural areas that depend upon it as a livelihood. These storms bury seedlings under sand deposits, reducing crop yields. They sandblast plants, which can lead to the loss of plant tissue and reduced photosynthetic activity, as well as delayed plant development. They can injure livestock and reduce their productivity. In addition, sediment can fill up irrigation canals, also leading to closed transportation routes and affected water quality of rivers and streams.
Sandstorms can provide certain benefits, however. Windborne deposits of sand and dust are a source of micronutrients for ecosystems around the world: Saharan dust, for example, is believed to fertilize the Amazon rainforest. Plus, the iron and phosphorus transported during dust storms can benefit marine biomass production in parts of the oceans lacking these elements.
Like all weather phenomena, sandstorms are neither good nor bad on their own — they’re just changing due to climate change. And more unpredictable weather can cause chaos and confusion for people living in affected locations.
