Causes and consequences of climate change

Humans are exerting an increasing influence on the climate and on the variation of the earth's temperature, in particular through activities such as: the burning of fossil fuels; deforestation; and livestock farming. These activities add huge amounts of greenhouse gases to those naturally present in the atmosphere, thus increasing the natural greenhouse effect and determining the phenomenon of global warming. Greenhouse gases are so called because they act much like the glass of a greenhouse, capturing the heat emitted by the Earth after receiving solar energy, preventing it from returning to space (thus trapping it in the atmosphere). Many of these gases are present in nature, but human activity is increasing the concentrations of some of them in the atmosphere, in particular: carbon dioxide, methane, nitrous oxide, fluorinated gases... CO2 is a greenhouse gas produced mainly by human activity and is responsible for 63% of the global warming caused by mankind (its concentration in the atmosphere currently exceeds 40% of the level recorded at the beginning of the industrial era, now exceeding the concentration of 400 ppm in the atmosphere). Other greenhouse gases are emitted into the atmosphere in smaller quantities but have a much higher "greenhouse capacity" than CO2, i.e. they are capable of capturing much more heat than CO2, sometimes thousands of times more. Methane is responsible for 19% of man-made global warming, nitrous oxide for 6%. The objective set in 2015 at the COP 21 in Paris is linked to controlling the increase in the Earth's temperature "well below" +2°C compared to the pre-industrial era, in order to avoid consequences that are too great for the planet - but above all for mankind.

The consequences of climate change

First of all, it must be stressed that climate change affects - and will affect - all regions of the world, albeit in different ways and in different forms. Generally speaking, a huge category of consequences can be expected, such as the melting of the polar ice caps and perennial ice, rising sea levels, an increase in the frequency and intensity of extreme weather events, changes in the annual distribution of precipitation, and increased hydrogeological and flood risks, increased risk of drought and fire, increased heat waves with health consequences for the population, change in the distribution of animal habitats, disappearance of species, change in the distribution of snow and certain water-borne diseases, extension of the range of action of insects, vector diseases (insects, etc.), and the spread of diseases such as malaria, tuberculosis and tuberculosis. )), changes in agricultural productivity and nutritional quality/capacity.

Implications for Europe

First of all, it should be pointed out that temperatures in Europe are rising, with a sharp increase since the early 2000s: As a result, heat waves, forest fires and droughts are increasingly frequent in central and southern Europe. The Mediterranean is becoming an arid region, making it even more vulnerable to drought and forest fires. Northern Europe is becoming much wetter and winter flooding could become a recurring phenomenon. Urban areas, where 4 out of 5 Europeans live today, are exposed to heat waves, floods and rising sea levels, but are often unprepared to adapt to climate change.

Implications for developing countries

Developing countries are often severely affected. Their populations are generally highly dependent on their natural habitat and have few resources to cope with climate change.

Risks to human health

Climate change is already having an impact on health. In some regions, there is an increase in the number of deaths due to heat and in others there is an increase in the number of deaths due to cold.

Costs to society and the economy

Damage to housing, infrastructure and human health results in high costs to society and the economy. Between 1980 and 2011, floods affected more than 5.5 million people in Europe and caused direct economic losses of more than EUR 90 billion, while in Europe alone, extreme weather and climate events caused economic losses totalling EUR 433 billion over the period 1980-2016. Sectors that are highly dependent on certain temperatures and precipitation levels, such as agriculture, forestry, energy and tourism, are particularly affected.

Risks to wildlife

Climate change is occurring at such a rapid pace that many plant and animal species are struggling to adapt. Many terrestrial, marine and freshwater species have already moved to other regions. Some plant and animal species will be at greater risk of extinction if the global average temperature continues to rise uncontrollably.

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