The ozone concentration increases with the currently high temperatures.
Sore throat, cough or headache and increased asthma attacks – these can be the consequences of increased ozone concentrations in the air we breathe. When exercising outdoors, there is a risk of a reduction in lung function and physical performance in general.
The current heat wave has caused the ozone levels in Germany to rise sharply. As early as Monday, 15 measuring points reported that the “information threshold value” of 180 micrograms of ozone per cubic meter was exceeded. A warning is issued from 240 micrograms because such high ozone concentrations are hazardous to the health of the entire population.
Fires drive up values
The ozone forecast by the Federal Environment Agency predicted ozone levels of over 180 micrograms on Tuesday up to and including today, mainly for Baden-Württemberg, Hesse, North Rhine-Westphalia and Lower Saxony, with most of the exceedances expected on Tuesday in North Rhine-Westphalia and on Wednesday in Hesse became. In isolated cases, the warning threshold could also be exceeded, it said.
Ground-level ozone (molecule: O3) is formed when sunlight hits pollutants such as those from traffic, such as nitrogen dioxide, or volatile organic compounds from solvents. The pollution on the outskirts of conurbations or in rural areas is often higher than in the centers, since the ozone produced there is broken down again by other exhaust gases such as nitrogen monoxide that are present in large quantities.
Meanwhile, the European earth observation program Copernicus reported that southern European countries had already recorded extremely high ozone pollution last week, particularly in Spain and Portugal and parts of northern Italy. The heat wave that has been going on there for a long time and the devastating forest fires on the Iberian Peninsula have led to the values rising to over 200 micrograms per cubic meter.
Mark Parrington, senior scientist at the Copernicus Atmosphere Monitoring Service (CAMS), warned: “The human health impacts of very high levels of ozone exposure can be significant in terms of both respiratory and cardiovascular disease.” He cited estimates , according to which ozone pollution causes about one million additional deaths worldwide every year. “That’s why it’s so important that we continuously monitor ozone levels at the Earth’s surface.”
decline since the 1990s
In Germany, the average peak values for ozone pollution have decreased significantly since the mid-1990s. The cause is improved air pollution control, for example thanks to car catalytic converters and nitrogen filters in coal-fired power plants. However, according to the Federal Environment Agency, the target value for the protection of human health valid in the EU – 120 micrograms of ozone per cubic meter in the eight-hour average – is still exceeded, as an evaluation in autumn 2021 showed. In addition, in contrast to the development of the peak values, the annual mean ozone values in urban residential areas even increased in the same period.
Incidentally, in the stratosphere above an altitude of 15 kilometers, ozone has a positive function for humans, animals and plants. The ozone layer found there protects against UV radiation.
