Tokyo, 5 August, 2021 – Scorching temperatures are becoming much more frequent in cities across East Asia, according to a new analysis from Greenpeace East Asia. Researchers analyzed temperature data for 57 cities across China Mainland, Korea and Japan and found that hot weather was arriving earlier in the year in more than 80% of cities.

“Over the past two weeks we have seen multiple Olympic athletes collapse due to heat stroke. Earlier this summer, extreme temperatures in Guangdong, China forced factories to shut down, and in Korea hundreds of thousands of livestock were reported dead due to heat waves. These extreme heat events are consistent with the region’s changing climate. Dangerous temperatures will only become more frequent unless governments switch from polluting fossil fuels to cleaner energy sources, including wind and solar,” said Greenpeace East Asia climate urgency project manager Mikyoung Kim.

In Tokyo and Seoul, the first hot day of the year (30​​°C or higher) arrived on average 11 days earlier during the period 2001-2020 compared to the previous two decades. In Shanghai, the first hot day arrived 12 days earlier, and in Sapporo it shifted forward a full 23 days.

Cities across the region are experiencing increasingly severe and frequent heat waves, according to the research. Between 2001 and 2020, the frequency of heat waves in Beijing was nearly three times that of the previous 40-year period. In Tokyo the number of days with a temperature of 33°C or higher has more than doubled since the 1960s, the analysis shows.

Extreme temperatures and the early arrival of hot weather cause severe ecosystem, agriculture and health impacts. The elderly, people who work outdoors, and those with chronic health conditions are particularly at risk. Between 2000 and 2018, heat-related deaths in people over the age of 65 increased by 54% worldwide, with Japan and eastern China facing disproportionate impacts.

Greenpeace East Asia urges that governments take action to reduce emissions of climate change-causing greenhouse gases.

“Governments must take immediate measures to protect people’s health amid extreme weather.  There is an urgent need to strengthen climate targets, including an end to all financing of the fossil fuel industry, and implement a switch to 100% renewable energy as quickly as possible,” said Kim.



Temperature data for each city is available here.

Analysis is available here.

Temperature data is from the Japan Meteorological Agency, Korea Meteorological Administration and Global Historical Climatology Network (GHCN). This study adopts a threshold of 30C to define “hot days” and 33C to define “extreme hot days.” In each region, cities were selected based on population size. Cities with insufficient temperature records were excluded from the analysis. Please refer to the report Climate Risk in Chinese Cities: Identifying At-Risk Communities for temperature analysis of China Mainland cities.


Erin Newport, International Communications Officer, Greenpeace East Asia: +886 958​ 026 791, [email protected]