Extreme heat hits cities earlier, temperatures higher than before

The Central Meteorological Observatory of China issued the country's first orange alert in 2024 for high temperatures on June 9.

China has a four-tier, color-coded weather warning system, with red representing the most severe warning, followed by orange, yellow and blue.

This year's first orange alert came earlier than in previous years, with it being issued on June 17 in 2022 and on June 22 in 2023.

Extreme high temperatures occur not only in China, but affect almost the entire Northern Hemisphere, and are coming earlier and are more intense, said Wei Ke, a research fellow at the Institute of Atmospheric Physics of the Chinese Academy of Sciences.

Temperatures exceeded 38 degrees Celsius in southwestern parts of the United States in early June. The temperature in Phoenix, the capital of Arizona, reached 45 degrees Celsius on June 6, and Las Vegas, Nevada, reached 48.3 degrees Celsius on June 7. Both have broken records and the extreme heat occurred about two weeks earlier than in previous years.

In early April, temperatures in parts of Thailand, Vietnam and the Philippines exceeded 40 degrees Celsius. Many Pakistani cities faced heat waves with temperatures approaching 50 degrees Celsius in late May.

India has had more than 16,000 cases of heat stroke since March 1. Temperatures in its northern states and capital New Delhi have continued to rise, with the highest record approaching 50 degrees Celsius this month.

Extreme high temperatures are not only a threat to human health, but also aggravate drought, cause wildfires and impact agricultural production and urban power systems.

According to the report "The Human Cost of Disasters 2000-2019" released by the United Nations Office for Disaster Risk Reduction, the number of extreme high temperature events worldwide has increased by 232 percent over the past 20 years. "The days just get hotter and hotter," said Wei. "The reasons for the frequent occurrence of extreme high temperature events are diverse, including special weather conditions and the general background of global climate change."

Countries around the world are taking climate actions, but the progress appears slow. Heating up globally is inevitable in the next few decades. Extreme high temperatures, which were rare previously, are becoming more and more common. The world has entered a "new normal" with temperatures above 40 degrees Celsius.

In addition to accurate monitoring, forecasting and early warning, society's adaptability to climate change must be improved. Public awareness must be raised so that more can understand the impact of climate change on their lives and take protective measures, Wei said.

"Our cities are not ready for a world with continuous high temperatures over 40 degrees Celsius. More greenery should be added to streets and squares to improve the cities' heat resistance and ventilation. Emergency measures and long-term adaptive constructions should be combined for people to better protect themselves in the scorching summer," Wei noted.

(Cover: People play beach volleyball in Domino Park in Brooklyn, New York, as a heat wave hits the northeast United States on June 18, 2024. /CFP)