Recently, a new study found that the Colorado River, an important river in the United States, is in danger of drying up due to global warming, and millions of people who depend on the river are expected to face the risk of "serious water shortage". More than half of the Colorado River's lost flow is related to rising temperatures, according to a study published in science on February 20 local time, CNN reported Monday.
The researchers found that for every 1.8 degrees Fahrenheit (about 1 degree Celsius) warming in the river basin, the flow decreased by nearly 10%. Between the 20th century and the beginning of the 21st century, the region has risen by an average of about 1.6 degrees Fahrenheit (about 0.9 degrees Celsius). At present, the flow of this river has been reduced by 20% compared with last century.
Brad Udall, a senior climate scientist at Colorado State University, said the current flow of the Colorado River was not optimistic. When it flowed into the Gulf of California, the flow had been reduced to a "trickle".
Scientists have found that the river's problems existed before it reached the city - global warming is seriously damaging the snow that feeds the river. As temperatures rise, snow is falling at the source of the river, which means less energy is reflected from the ground and more heat is left on the ground, leading to more evaporation and less flow.
The Colorado River originates from the Rockies in Colorado and Wyoming, winds through the southwest of the United States and flows into the Gulf of California, providing water for more than 40 million people along the coast, agricultural development of coastal cities and food for millions of people around the world. This important river supports about 1 trillion US dollars (7 trillion RMB) of economic activities every year.
It is understood that for most of the past 20 years, due to the sharp decrease of river flow, its two main reservoirs, Lake Powell and Lake Mead, can only barely hold half of the water.
It also exacerbates the controversy over water resources in the Colorado River region. In 2019, seven states that rely on river water sources reached a new agreement to allocate their rights to manage water resources by 2026.
However, scientists Chris Miley and Christa A. Deng, the authors of the latest study, believe the only way to save the river is to address the root causes of the problem: climate change. And said that no matter what measures are taken, the flow may be reduced, but without curbing climate change, the Colorado River flow may be reduced by 19 to 31 percent by the middle of the century.
"Science is very clear - we must immediately reduce greenhouse gas emissions. We have technology, policies and favorable economic conditions to achieve greenhouse gas emission reduction, but what we lack is will," said Udall, a climatologist.