Unusual summer alerts in the tropics

Tropical regions in Africa, Asia and South America may witness 'the long-term emergence of unprecedented summer heat' in the next 20 years - scientists have warned.

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The tropics and most of the northern hemisphere will experience a rise in summer temperatures if greenhouse gas emissions continue to rise at the current rate.

Red sand dunes in Namibia. Most of Africa, Asia and South America can witness
Unusual heat of summer .

Researchers at Stanford University say that North America, including the US, southern Europe and China, is vulnerable to extreme changes in summer temperatures over the next 60 years. This major change will be able to have serious consequences for human health, and to agricultural production and ecosystems.

The author of the study by Noah Diffenbaugh said: ' According to our predictions, large areas of the Earth are prone to heat up so quickly that by the middle of the century, even the coolest summers will be hotter. the hottest summer of the last 50 years '- he said - ' When scientists talk about global warming causing heat waves, people often ask if that means the highest temperature will become 'new average ' or not "

To determine the effect of the season on global warming in the coming decades, Dr. Diffenbaugh and colleagues analyzed more than 50 experimental models. Among them are simulations in the 21st century when the concentration of greenhouse gases is expected to increase.

The simulations of the 20th century had previously "correctly" guessed the Earth's climate over the past 50 years. An example of serious consequences caused by harsh summer, Dr. Diffenbaugh points out that the record heat waves in Europe in 2003 killed 40,000 people.