Climate change is a reality we can’t stop. As the Earth’s climate warms, cases of extreme heat and humidity are increasing, which is having a significant impact on human health. Climate scientists are tracking a key measure of heat stress that could warn us of harmful conditions. Spain has not escaped this either, and NASA itself has revealed the cities that will be uninhabitable in 2050.
“The extreme level of heat stress They have more than doubled in the last 40 years. And this trend is expected to continue,” he explains. colin raymond from NASA’s Jet Propulsion Laboratory in Southern California and lead author of the study “Too Hot to Handle: How Climate Change May Make Some Places Too Hot to Live,” published in Science Advances.
In this context, the report points out, meteorologists use various tools to evaluate the likelihood of thermal stress. In fact, heat stress measurements are prominently featured in daily weather reports. In addition to forecasts of Temperature and Relative Humidityyou’ll see something called the heat index or apparent temperature. The heat index is a measure of the air temperature we feel when relative humidity is taken into account. Calculated for shaded areas, the heat index shows how uncomfortable we feel when it’s hot and humid.
Importance of Wet Bulb Temperature
Raymond argues that The highest wet bulb temperature that a human can survive This is about 35 degrees Celsius when exposed to the elements for at least six hours. The issue, according to the study, is that wet bulb temperatures are rising around the world and the Earth’s climate is starting to exceed this limit.
wet bulb temperature The minimum temperature to which an object can cool when moisture evaporates. The lower the wet bulb temperature, the easier it is for us to cool down. It measures our body’s ability to cool itself through sweating when it’s hot and humid, and tells us if conditions could be harmful or even fatal to our health.
The results have important implications. The hotter it is, The more stressed our bodies feel the more we need to sweat to cool down.. But humid air is less able to hold extra moisture, so water evaporates more slowly in humid conditions.
“Once the wet bulb temperature exceeds 35 °C (95 °F), No amount of sweating or other adaptive behavior is enough to bring the body up to a safe operating temperature” Raymond explains. “Most of the time this is not a problem, as the wet bulb temperature is typically 5 to 10 degrees Celsius below body temperature, even in hot and humid places,” he adds.
Future hot spots
Raymond says it’s hard to predict when we might see global wet-bulb temperatures regularly exceed 35 degrees Celsius. That’s because it’s a complex process that happens gradually and develops differently in different places. But climate models tell us it’s likely Some regions will warm even more in the next 30 to 50 years. The most vulnerable regions include South Asia, the Persian Gulf and the Red Sea around 2050; and eastern China, parts of Southeast Asia and Brazil by 2070. The United States, however, is not immune. “Within 50 years, Midwestern states such as Arkansas, Missouri and Iowa will likely reach the critical wet-bulb temperature threshold,” he added.
Urban heat islands and the areas of Spain “in danger”
Apart from global warming, there is another phenomenon that contributes to the increase in temperature in cities and it is called “Urban Heat Island”; These are urban areas that are hotter than the surrounding rural areas.
According to a UN report, some of the origins and solutions of these risk factors are similar to climate change, particularly in the energy and transport sectors, and are particularly important as urbanisation increases. The intensity of urbanisation and population growth contribute greatly to non-communicable diseases and climate change. Urban areas facilitate activity in multiple areas where interventions can be made.So, far from presenting enormous challenges, urban areas also provide great opportunities for achieving positive and lasting change.
According to NASA’s report regarding Spain, the region of Madrid, the Valencian Community and Andalusia In 2050 more than three months will be experienced with temperatures of 35 degrees or more. To manifest this scenario, the space agency has taken into account the relationship between temperature and humidity, so if only the maximum degrees are achieved the number of uninhabitable areas could increase.
How satellites can help
Many locations with extreme wet-bulb temperatures are in developing countries in the subtropics, where there are few reliable long-term weather stations. This makes it difficult to fully understand extreme heat events. However Satellite data can help identify hot spots and the processes that increase the wet bulb temperature at those locations.