Environment. In North America, heat wave is “almost impossible” without global warming

In late June, a heat wave hit western North America. The states of Washington and Oregon in the United States found themselves under a “dome of heat”, and Canada also faced extreme mercury, with high pressures catching hot air. Temperature records across the country have been broken several times, especially in the village of Lytton on June 30, which was completely destroyed by severe fires. The exact human number of this heat wave is not yet known, but at least several hundred deaths.

According to scientists from World weather characteristic (1), an effort to bring together experts from various research institutes around the world, said on Wednesday that these phenomena were “almost impossible” without human-caused global warming.

The exception is June

The temperature experienced in North America is actually extraordinary compared to the regular averages recorded in this region. June 2021 is the warmest month since the start of the measurements: it averaged 1.2 C during the period 1991-2020, which means that in June 2012 the region was warmer than the previous June at 0.15 C.

With 2 ° C warming (which is likely to occur in early 2050) the global meteorological characteristic is that by the end of June the US western temperature would have been as high as 1 ° C. After all, there is a probability that such an event will recur every 5 to 10 years.

The temperature of this heat wave in litton in red. We see that they are completely stagnant compared to the average.

Scientists have determined that if this episode of extreme heat had occurred at the beginning of the Industrial Revolution, the recorded temperatures would have been about 2 C higher than they were. According to them, with the current climate, such a heat wave could occur statistically once every 1000 years.

With regard to the “heat dome”, this climatic phenomenon was not unprecedented, but more powerful than ever observed.

Call for action

As for the future, two scenarios are possible, according to researchers. First, although the climate crisis has made such an event quite possible, it is still rare. The second is of great concern: the general rise in temperature may exceed a threshold, which could lead to higher-speed warming than previously predicted, and current climate models fail to predict.

Scientists therefore call for action: to take action in accordance with these new conditions, especially for the construction of high heat warning systems and suitable buildings for the population. But most of all, in the long run, to reduce greenhouse gas emissions at all costs, they hammer home.

(1) The global meteorological characteristic has made a specialization in analyzing the possible relationship between a particular extreme weather event and global warming, by calculating the probability that it will occur even in the shortest possible time. The greenhouse is connected to the exhaust. Here, 27 researchers from seven different countries participated in the analysis.