At 40°C, heat in the Midwest reaches historic levels – 10/20/2023 – Daily Life

After the dangerous heat that passed through the country recently, another heat wave is occurring in the country. This time, however, the very high temperatures are concentrated in the Center-West of the country. Cuiabá, capital of Mato Grosso, is already passing and will continue to spend the next few days above 40°C.

Inmet (National Institute of Meteorology) points out great danger and health risk for almost the entire state of Mato Grosso, for the northern portion of Mato Grosso do Sul, for the southern slice of Amazonas and for stretches close to the borders of Mato Grosso with Tocantins and Goiás.

According to Inmet, this area has and will have, for the next few days, temperatures up to 5°C above average, for a period longer than five days. The Inmet alert began late this Friday afternoon (20).

MetSul Meterologia predicts that the region will reach levels never before recorded in the country with temperatures of up to 46°C between Friday and the beginning of next week.

The capital Cuiabá is expected to record the highest temperatures. On Thursday afternoon, the maximum temperature in the city reached 44.2°C, and the municipality entered the list of the ten highest temperatures ever officially recorded in Brazil, by Inmet. It was the highest temperature in the capital’s history.

According to Estael Sias, meteorologist and managing partner of MetSul, the heat experienced by the region in question is explained by a sequence of events. “It’s a seasonal condition. The drier climate in late autumn, winter and early spring. There was already an extreme heat wave in September. The rain did not return in sufficient conditions for the soil to recover and prevent a new heat wave “, says the expert.

Taking Cuiabá as an example again, Inmet points out that, in September, the average temperature in the month was 31°C, a value 3°C higher than the climatological normal (i.e., the historical average). Furthermore, the volume of rainfall was 30% lower than the climatological normal. In August, the city was also more than 3°C above the historical average, but with a volume of rain (14.4 millimeters) also slightly exceeding (9%) the climatological normal.

Sias says there’s a huge mass of dry, hot air causing a so-called “heat dome” — imagine trapped hot air causing more warming through compression. According to the meteorologist, very hot air dries out vegetation and very dry soil ends up radiating even more heat.

“One condition intensifies the other and this heat dome is formed. Rain does not enter this area. It is a lid that keeps this heat on the surface”, says Sias, who points out that temperatures can exceed 45°C in the affected region by the heat wave.

The hot air mass will bring the same intense heat to states in other regions, such as the north of São Paulo, Minas Gerais, Tocantins, Rondônia and the south of Amazonas and the state of Pará.

All will also have highs of 40ºC or more in the coming days. In some cities, which do not have instrumental temperature measurement, even higher maximums can be recorded

“Two waves of extreme heat in the same year really draw attention. And also catching areas of repetition”, points out Sias. Although El Niño and seasonal drought contribute to the situation, the meteorologist points to the climate crisis as another actor to consider.

Recommendations from health experts include drinking plenty of fluids, wearing light clothing, protecting yourself with a hat, sunglasses, using sunscreen and avoiding physical exertion during the hottest hours of the day.

Climate crisis increased the chance of a recent heat wave in Brazil by 100 times

A recent attribution study found that the climate crisis generated by human action increased the chance of extreme heat — like the one seen at the end of September in Brazil — occurring by up to a hundred times.

Even looking at a more restricted period of time within the heat wave that occurred in August and September this year, scientists pointed out that there were extremely high temperatures for more than 50 consecutive days in Brazil.

According to the analysis carried out by WWA (World Weather Attribution), without global warming caused by humans —associated mainly with the burning of fossil fuels, but also with actions such as deforestation—, the heat at the end of winter and at the beginning of spring in Brazil it would be 1.4°C to up to 4.3°C lower.

The analysis done by WWA is an attribution study. Such research, based on climate models, compares the chance of an event in the current world, that is, in the presence of the climate crisis, and in a world without the increase in temperature caused by human action.