Visualize how many people will be seriously affected by the heat and heat waves by 2100

In July 2010, Moscow died of thousands of citizens from the record hot weather and air pollution, the death toll was 1.5 times the same month of the previous year. There are many news reports on how hot heat and heat waves affect people, but on the other hand, how will people be influenced by future heat waves? It is said that prediction is difficult. Meanwhile, Camilo Mora, a geographer at the University of Hawai'i, found that from 900 studies of 784 heat waves that occurred in 36 countries around the world, people who are severely affected by heat waves are expected to recover by 2100 It analyzes and predicts whether it increases, and makes it visible on the world map.

Global risk of deadly heat: Nature Climate Change: Nature Research
https://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3322.html

Heat can kill and we're turning up the thermostat | Ars Technica
https://arstechnica.com/science/2017/06/heat-can-kill-and-were-turning-up-the-thermostat/

The research team first defined a "dangerous line" where human bodies are seriously affected by environmental factors such as temperature and humidity. The power of heat dissipation of the human body decreases as the ambient temperature approaches body temperature. In addition, people radiate heat from the body surface using a mechanism that evaporates sweat, but when the humidity is high, sweat does not evaporate and heat can not be dissipated, so you can not lower body temperature. For this reason, even if the temperature is lower than the body temperature, humans will overheat if the humidity is high. Researchers investigated the frequency of such overheating occurring all over the world and at what frequency. Then, for example, in 2000, 30% of people in the total population of 13% of the earth were experiencing the environment beyond this dangerous line. Many of them are tropical areas including Southeast Asia and India.

After that, researchers applied the above analysis to "some scenarios of global warming that greenhouse gases are thought to bring by the year 2100". Then, in the scenario that "The greenhouse gas could be reduced to the utmost," the temperature rise is only two times before the Industrial Revolution and 2100 compared to the scenario, but still the heat that is dangerous to the body We found that the percentage of people experiencing waves rose from 30% to 48%.

The influence of heat waves on people is visualized on the following website.

Deadly Heatwaves
https://maps.esri.com/globalriskofdeadlyheat/


By opening the tab "Year" on the right side of the screen, you can see how many people will receive the influence of dangerous levels of heat waves from 1950 to 2100. When "2100" is selected ... ...


By default the setting is "RCP 2.6 (when greenhouse gas emissions are greatly suppressed)", so the 2100 year risk level assumed in RCP 2.6 was displayed.


The coloring is as follows and the area where there is a day that goes over the danger line for more than 50 years a year becomes yellow, and as the color gets darker from it, the number of days over the danger line will increase.


On the other hand, if set to "RCP 8.5" assuming that the emission of greenhouse gases will continue to increase, three-quarters of the population will cross over 20 danger lines each year He said he was experiencing heat waves. In wet tropical areas it will cross this danger line nearly every day and it is thought that heat waves of more than 50 days per year will affect people in most of the earth, including Africa, Australia and southern New York. When I looked at the map in Japan, it is clear that there are more than 50 days of intense heat waves annually in the northern and northeast regions from Tokyo.


The tropical region where there is a trend of population increase · urbanization and the region where the number of elderly people are increasing, the more serious the influence of heat wave is. Researchers commented, "The research we announced strongly insists on the importance of actively reducing the risks in regions where the risk of death is high and the areas where adaptation to the environment is needed I am talking. "