Why is the hot summer heat more and more intense?

According to the World Meteorological Organization (WWO), from the summer of 2016, the recent years have been the hottest period in the northern hemisphere in the record of the climate for 140 years . Unusually high temperatures in the first half of 2016 due to El Nino weather phenomenon.

Although greenhouse gas emissions have decreased recently, the summer of 2020 is expected to break the previous record.

According to the forecast, in 2020, the temperature in the world may be higher than the average temperature of about 1 degree Celsius . 2020 is expected to break all temperature records, extending the string of erratic weather phenomena over the years.

The National Oceanic and Atmospheric Administration (NOAA) and the United Kingdom Meteorological Agency (Met Office) both believe that the likelihood of 2020 will be one of the highest temperature years. NOAA estimates that the hottest year in meteorology history is 75%, otherwise, 99.9% will be in the top 5 of the hottest years.

Extreme temperatures are becoming more common and more intense

A research project by scientists found that, if humans did not take measures to reduce pollution from heat-trapping emissions, there would be three-fourths of summer days in most of the Northern Hemisphere. Extremely high temperatures.

Research shows that the number of extreme hot days is increasing. Since 1960, there are currently about 5 days of hotter special days in the Northern Hemisphere and these days are about 2.7 ° F (1.5 ° C) hotter.

It's a period of time and intense heat can be deadly, according to Dr. Kristie Ebi, a professor at the Center for Global Health and Environment at the University of Washington.

A construction worker washes his face by a tap to cool down in Washington, DC, USA during the heatwave of July 2019. (Photo: CNN).

The authors of the study said that the increase in both frequency and intensity of hot days and nights is mainly due to the pollution of warming gases from the human planet - that is, natural combustion. fossil fuels and other sources.

The study also found that the regions saw the largest increases during extreme hot days - South America, Northwest and Southeast Canada, Western and Southern Europe, Mongolia, Southeast China - may feel hotter in the coming decades.

Heat waves in recent years in Europe and India have led to tens of thousands of deaths.

While temperatures rise dramatically, the prediction shows whether or not the summer is hotter in the future will depend on the actions of people today to reduce pollution from the gases that trap heat in the atmosphere. , according to CNN .

Under a fairly optimistic scenario, if humans continue to burn fossil fuels but take steps to reduce greenhouse gases in the coming decades, the number of days of extreme temperatures every summer can increase from around 8 to 32 days before 2100 - 4 times the number of hot days recorded in 2012.

But if humans fail to reduce pollution from heat-trapping gases, many parts of the Northern Hemisphere can catch about 69 days of devastating daytime and nighttime heat by 2100 - eight times more. with 2012.

The study also found that the number of people exposed to extreme hot days would increase. Even as the world develops towards a sustainable future with moderate emissions reductions and low population growth, the population exposed to extremely hot days can quadruple in the Northern Hemisphere.

And if pollution from heat-keeping emissions continues to go unmanaged, human exposure to this near-constant summer heat could multiply eight times by the end of the 21st century.

Health is seriously affected by extreme temperatures

Historically, heat waves have been an extremely dangerous weather pattern, making the average number of deaths more than floods, cyclones and even storms, according to National Weather Service.

While daytime heat is undoubtedly dangerous to human health, the risk increases when combined with high night temperatures. ' If you have hot days and then can't cool down at night, the physiological mechanisms that regulate the heat in our bodies are affected,' says Dr. Ebi.

The poor, living alone, the elderly and those with poor health are most vulnerable to heat , according to Jane Wilson Baldwin, researcher at the Lamont-Doherty Earth Observatory at the University. study Columbia.

'They can stay in their apartment alone, the heat accumulates and they don't have air conditioning , ' Mr. Baldwin said. ' After that, heat stress can lead to cardiovascular or respiratory effects that kill them.'