An extreme heat wave is leading to dramatic situations in Mexico, with water shortages in many regions and nearly 40 percent of the country’s water supply. natural reservoirs, the water level has dropped by half. Record high temperatures are also being recorded in Central America, parts of the United States and Guatemala. Meteorologists point out that the current situation in these areas is responsible for the so-called “”new” situation. heat dome.
What is a heat dome and why is it such a nuisance?
A heat dome is a meteorological phenomenon in which bands of high pressure persist over a region for an extended period of time, trapping warm ocean air and causing air temperatures to rise. They lead to extreme heat that can last for days or even weeks. This phenomenon in 2015. in Poland resulted in the persistence of a heat wave for more than a month.
As mentioned above, the mechanism for the formation of heat domes is the result of strong, high atmospheric pressure, which acts as a kind of lid that restricts air movement in the vertical direction. This phenomenon causes the air to be forced downward, leading to adiabatic heating, resulting in the accumulation and trapping of heat in the lower layers of the atmosphere. Temperatures in the “heat ceiling” thus created can exceed 45°C, creating a dense layer of heat over the area. This process is further compounded by the lack of wind, which significantly reduces natural air exchange and hinders the dissipation of accumulated heat. The weak winds occurring at this time are unable to significantly modify the position of the stable atmospheric high, which extends up to the high layers of the troposphere.
Heat waves caused by heat domes are just one of many serious consequences of this meteorological phenomenon. The accompanying effects of high temperatures, low humidity and minimal cloud cover contribute to extreme drought conditions, which in turn increase the risk of forest fires. In addition, heat domes can lead to serious infrastructure problems, including damage to road surfaces and overloading of power grids, which contributes to frequent power outages and interruptions. Such phenomena pose significant challenges to crisis management and require comprehensive adaptation and prevention strategies.
Extreme high temperatures are more dangerous than floods and earthquakes
Although heat waves are less violent than floods or earthquakes, they are considered one of the deadliest weather events. In 2023, Europe experienced another disastrous summer in terms of heatwaves, which caused a significant increase in deaths. High temperatures have affected Mediterranean countries such as Italy, Spain and Greece the most.
2023 was the warmest or second warmest year on record, depending on the dataset,” WMO. Over the past 20 years, heat-related mortality has increased by about 30 percent, with an estimated 94 percent of monitored European regions experiencing an increase in heat-related deaths.
The hot air mass currently lingering over Mexico is also taking a deadly toll. As a result of its impact, nearly 50 people have died in the region so far. Impacts associated with this phenomenon also affect fauna. Typical of regions in Mexico, howler monkeys experience fatal heatstroke due to extreme temperatures and limited access to water. As experts from the Institute of Atmospheric Sciences and Climate Change at the National Autonomous University of Mexico (UNAM) point out, the meteorological conditions currently being observed are only a prelude to an intensifying heat wave, which could herald a further deepening of the environmental crisis and increased threats to local ecosystems.
In Texas, Florida and other southern parts of the country, on the other hand, temperatures as high as 46°C are forecast for the coming week. Because of this, 4 million people have received warnings about critical conditions conducive to wildfires. Guatemala is also currently facing a heat wave. The growing number of fires in the country, caused by extreme soil drying, is becoming a growing threat. As a result of this and record high temperatures, authorities in the capital have decided to ban outdoor school activities.
Current heat waves the result of climate change
The current extreme high temperatures recorded in Mexico, southern regions of the United States and Central America are the result of climate change and increasing global warming, according to scientists. According to a 2020 study by researchers at UNSW Sydney and UNSW Canberraod since 1950. a significant increase in the frequency and duration of hot weather has been reported around the world. In the Amazon rainforest, for example, the period increases by five and a half days each decade, and in the Mediterranean region by two and a half days.
Global warming is also being felt in our country. According to IMGW-PIB, from 1970 to 2020, the average annual temperature in Poland rose from 7.2 degrees to 9.1 degrees. In contrast, the number of hot days has tripled to 15 per year. Given the above data, meteorologists’ predictions for the coming summer, which we wrote about in the 11/2024 issue of Water Matters, are also not optimistic. According to them, we are facing the hottest months in thousands of years. Their greatest consequences will be felt mainly by urban residents. The ubiquitous concrete in them resulting in heat islands, will threaten nearly 75 percent of the Europe’s population.