Drought causes Yangtze to shrink

A record-breaking drought has caused parts of the Yangtze River to dry up – affecting hydropower, shipping routes, limiting drinking water supplies and even revealing previously submerged Buddhist statues.

The Yangtze is China’s most important river, providing water to more than 400 million Chinese people. This summer, it has reached record-low water levels with rainfall in the Yangtze basin around 45% lower than normal with entire sections and dozens of tributaries drying up. The loss of water flow to China’s extensive hydropower system has created problems in Sichuan, which receives more than 80% of its energy from hydropower.

Images captured by the Copernicus Sentinel-2 mission show a comparison of the Yangtze and Jialing rivers, near Chongqing, over the last three years. Higher than normal temperatures increase the evapotranspiration of the river’s waters and, together with missing precipitation, result in lower water levels and sediment transportation downstream, which explains the significant colour difference of the Yangtze in the 21 August 2022 acquisition. Several areas of dry and exposed riverbed can also be seen west of Chongqing.

Major rivers around the world are drying up as record-breaking heatwaves take their toll, including the Rhine and Po rivers in Europe as well as the Colorado River in the US. Sentinel-2 is a two-satellite mission to supply the coverage and data delivery needed for Europe’s Copernicus programme.

The mission’s frequent revisits over the same area and high spatial resolution allow changes in water bodies to be closely monitored, as well as measuring turbidity – giving a clear indication of health and pollution levels of rivers around the world. For more information on Sentinel-2, click here.