WMO: Extreme heat events seriously degrade air quality

Geneva, Sept 6 (EFE).- Extreme heat events, exacerbated by wildfires and the spread of desert dust, are severely degrading air quality around the world, with adverse impacts on human health and agriculture, according to data by the World Meteorological Organization (WMO) presented on Wednesday.

“Heatwaves are worsening air quality, affecting human health, ecosystems, agriculture and our daily lives,” said WMO Secretary-General Prof. Petteri Taalas.

“Climate change and air quality cannot be addressed in isolation. They go hand in hand and must be tackled together to break this vicious cycle,” he added.

Although the report presented on Wednesday examines uses data from 2022, experts did not hesitate to point out that on 2023 the situation has been “more extreme” in the northern hemisphere.

“July was the hottest month on record, with intense heat in many parts of the northern hemisphere, and this continued into August,” said Prof. Taalas.

“Wildfires ravaged large parts of Canada, caused tragic devastation and death in Hawaii, and also caused major damage and casualties in the Mediterranean region. This has led to dangerous air quality for many millions of people and sent plumes of smoke across the Atlantic and into the Arctic,” he added.

According to the data collected in 2022, exposure to ozone (which is harmful to human health near the Earth’s surface) exceeded the maximum level allowed at hundreds of points where the World Health Organization (WHO) monitors air quality.

Harmful levels were first recorded in southwestern Europe, but similar readings were later seen in central and northwestern Europe as the heat wave spread and dust from the Sahara desert reached the continent.

WMO scientist Dr. Lorenzo Labrador said that “heat waves and wildfires are closely linked. Smoke from wildfires contains a witches’ brew of chemicals that not only affect air quality and health, but also damage plants, ecosystems and human health.”

However, he also stated that “it would be inappropriate to say that because what we have seen so far is so serious, we can anticipate worse episodes of air pollution, there is a probability, but we cannot guarantee that it will be so”.

Regarding Latin America, Labrador told EFE that this region has the advantage of being very large, very green and with a relatively low population density, with urban centers that – in most cases – are not megacities.

“Therefore, it should not be so difficult to implement measures to control air quality, especially to reduce greenhouse gas emissions. Without a doubt, emission controls would have an almost immediate positive impact,” he explained.

In a vicious circle, poor air quality also has a negative impact on the ecosystem, as nitrogen, sulphur or ozone damage the environment and reduce crop yields.

The WMO pointed out that the loss of crops due to ozone ranges from -4.4% to -12.4% for staple crops, although in the case of soybeans and wheat, losses can reach 30% in key areas such as India and China. EFE is