What Natural Disasters Threaten Our Environment of Tomorrow ?
Since its creation, the Earth has suffered many avatars, and has always recovered from it. Will it be the same tomorrow? What natural disasters could our planet of tomorrow face and what are the impacts on the environment ?
The greenhouse effect
Present in trace amounts in the atmosphere, certain gases act like the windows of a greenhouse: they trap infrared rays and warm our planet. Without them, life on Earth would be impossible. But due to human activity, their concentration has increased: in the space of 150 years, that of carbon dioxide has thus increased by 30% and that of methane by 145%. As a result, since the end of the 19th century, the Earth has warmed from 0.3 to 0.6 degrees Celsius, while the sea level has risen from 10 to 25 cm. By 2100, average global warming could reach 1 to 3.5 degrees Celsius and the sea to rise from 15 to 95 cm ...
The extinction of species
The World Conservation Union estimates that, since 1600, 108 species of mammals have become extinct. This rate of extinction, 40 to 200 times higher than it should be under natural conditions, is attributable to human activities (deforestation, urbanization, pollution, fishing and excessive hunting, etc.).
The hole in the ozone layer
Ozone in the upper atmosphere protects us from harmful ultraviolet rays. Above the poles, this stratospheric ozone layer tends to shrink, due to the use of chlorofluorocarbons (CFCs): the chlorine they release accumulates in the polar zone during the winter and becomes destructive in the spring, with the return of solar radiation.
Since 1982, with the exception of the tropics, the reduction in the level of stratospheric ozone in the northern hemisphere is estimated at 6.5% and the decrease in the southern hemisphere by 9.5%.
Deforestation and desertification
Forests, which covered half of the continents 5,000 years ago, now account for only 20% of the surface. This deforestation causes the disappearance of many plant species, induces major disturbances in the water cycle, but also a strong erosion of the soil. With the exclusion of existing deserts, nearly a quarter of the world's emerged surface is thus threatened with desertification...
Pollution of all kinds
Since the beginning of the industrial era, in the 19th century, there has been a very marked increase in the atmospheric concentration of greenhouse gases (carbon dioxide, CFC, methane, nitrogen oxides), but also sulfur oxides which acidify precipitation.
Air, water and soil are also contaminated by pollutants that are both toxic and very persistent, including lead, cadmium, mercury, but also dioxins or hydrocarbons.
