Extreme flooding in South Korea this week submerged streets, cars and buildings, as torrential downpours brought more than a month’s worth of rainfall in the space of a few days. Between Monday and Wednesday a cumulative total of 525mm – a little over 20 inches – was recorded in Seoul.
At least nine people are confirmed to have died from the floods and many more are reported injured or missing. High rainfall rates and flooding during the monsoon season in South Korea is common, with average rainfall of up to 10mm a day and 250mm in the month of August. However, this week rainfall accumulations far exceeded these typical conditions.
We can expect to see continued extreme flooding scenarios into the future as average temperatures across the Korean peninsula have increased by about 1.7C since 1912. The warmer air is able to hold more moisture and therefore there will be more frequent and intense rainfall events.
East Asia has also been subject to extreme heat over the past week, particularly affecting China. The temperature at Shanghai’s Xujiahui station reached 40.1C on Thursday. Since records began in 1873 there have been 20 instances of temperatures surpassing 40C in Shanghai, six of which have occurred in 2022.
In addition to the extreme heat across China, drought is becoming an increasing problem, in particular for the Yangtze River basin, which comprises a fifth of the total area of China and contains a third of China’s population. As of July, the basin had seen 40% only of the rainfall it had during the same period last year, with some places seeing 20 consecutive days without any measurable rainfall.
Water levels in the main flow of the river are about 5 metres lower than this time last year. Drought is affecting 830,000 people, along with large areas of farmland. Throughout next week the basin is likely to see very little or any rain at all, with intense heat dominating and the drought worsening.