The climate on Earth depends a lot on the exchanges between the ground and the atmosphere. On a planetary scale, there are currently 2,500 billion tons of carbon stored in the soil, which represents two to three times more than in the atmosphere. What are the consequences of global warming on soils?
There are currently 2500 billion tonnes of CO2 stored in the soil (mainly in the form of organic matter), which represents two to three times more than in the atmosphere.
Ever-increasing temperatures risk increasing the decomposition and mineralization of the organic material in soils, thereby reducing the organic carbon content. Let’s imagine that all this C02 starts to be released…
What are the consequences of global warming on soils?
The first thing is that climate change could accelerate the risk of soil degradation and its main properties. This could impact the ability of soils to support ecosystems, which would further aggravate the impacts of human pressure.
Global warming could therefore have multiple consequences on soils, each more dramatic than the next.
1. Water regulation
Soils are involved in the water cycle. Soil quality determines the proportion of water that runs off and that which infiltrates. Soils thus regulate the groundwater fillingas well as the regime of the rivers.
If the temperature of the soil increases, the water risks evaporating more and there will therefore be less water to replenish the water tables and supply the rivers.
In addition, water infiltrating less on dry soils, this increases the risk of runoff and therefore of flooding of rivers and floods.
2. Floods
Healthy soil can prevent us from flooding. Especially with crops that limit erosion and capture water. Conversely, hard surface surfaces, such as the bitumen that covers the arteries of our cities, waterproof the floors. They promote water runoff. Urbanization is therefore an aggravating factor for flooding.
3. The melting of permafrost
The melting of permafrost, this permanently frozen layer of the basement, present under Alaska, Siberia or even the Arctic region, is another threat that has already become a reality. When it melts, permafrost releaseshuge amounts of CO2 in the environment, which further accelerates global warming and the unfortunate consequences for ecosystems.
Some scientists also warn of another equally terrible risk: the melting of permafrost can also release viruses and bacteria dormant for hundreds or even thousands of years.
4. Coastal erosion
Climate change is accelerating coastal erosion rates due to sea level rise and increased frequency of storms and extreme events.
Some ecosystems, such as dunes and salt marshes, provide natural buffers to help withstand severe storms.
Residents of all potentially affected coastal regions are encouraged to maintain the natural capacity of beaches, dunes, cliffs and salt marshes to move to earth as the sea level rises.
5. When floors sink or collapse
Faced with the central question “What are the consequences of global warming on the soil?” many studies also draw attention to the risks of landslides and soil collapse due to the destabilization of underground cavities.
Global warming is not the only cause, but it is what accentuates the drought phenomena which destabilize the soil. The other person responsible is, unsurprisingly, the Man who (as usual) depletes resources of the planet, starting with underground water reserves.
One of the most emblematic examples is Tehranthe Iranian capital with 13 million inhabitants including some parts sag from 25 centimeters per year. The reason ? By drawing water from its basement, the city depletes the water tables located under its foundations.
Read also:
The consequences of ocean warming
The consequences of melting glaciers and sea ice
The impact of global warming on soils
What does a temperature increase of +2°C mean?
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Mexico City also experienced a spectacular collapse 8 cm per year. The city was built on an ancient lake which rests on soft and very unstable clays. The city’s cathedral has been undergoing consolidation for several years…
The acceleration of global warming opens gloomy prospects for the future of many other cities in the world. Under the combined effect of land subsidence and rising waters, some are already doomed to disappear before the end of the century.
This is particularly the case of Venice which is sinking 0.8 to 1 cm per year. In the southern United States, Miami and the New Orleans are also at risk of being submerged by water before 2100, according to a study published in 2015 by the American Academy of Sciences.
What are the consequences of global warming on soils? Now you have an idea…
