Tesina di maturità in inglese sulle cause e conseguenze dei cambiamenti climatici (30 pagine formato pps)
CAMBIAMENTI CLIMATICI: TESINA MATURITA'
I cambiamenti climatici.
The greenhouse effect
This phenomenon is called "Greenhouse Effect": UVA rays are sent to the Earth from the sun, bouncing on the ground and become Infrared are returned to the atmosphere but they can't go outside because they find the layer of smog and remain imprisoned warming Earth's surface.
Consequently, the glaciers melt and flood coastal areas and increase flooding seaside city like Venice. The area of glaciers in the North Sea has been reduced by almost 10%, mountain. A few of mountains between 1850 and 1980 have lost about a third of their surface and half of their mass. (The Dolomites Marmolada glacier has lost Within a few years about 16 meters extension).
TESINA MATURITA' SUL CLIMA
The gulf stream
Another consequence of the greenhouse effect is the melting of glaciers and as a result the block of the Gulf Stream: the hot and salt water leaves the Mexico’s Gulf and arrives at the North Pole, during the way the water evaporates so its density grows, and it starts to go downward. For that reason the water is getting cold and it’s going down until it changes rout. If the melting of glaciers makes much fresh water, the salt water will not grow the density and will not go downward, so the Gulf Stream will be stopped.
Furthermore the increase of temperatures will lead to an increase of force 4 and 5 cyclones and typhoons and as has already been seen, in the last thirty-five years temperatures have doubled.
Because according to scientists the temperature could increase by 5.5° by 2100. The IPCC report lists the foreseeable calamities that will accompany this climatic disruption . Above 2° higher than the normal temperature of 1900, droughts will be increasingly catastrophic and frequent in third world territories, whilst in Northern regions there will be an increase in agriculture. In a comparatively short time afterwards the temperature will rise and between 1.1 and 1.3 billion people will die.
TESINA MATURITA' SUL CAMBIAMENTO CLIMATICO
Half the glaciers will melt and sea levels will increase dramatically, covering thousands of kilometres of coastline. Droughts, floods and temperature increases will be ideal conditions for tropical infections.
Animals and plants will experience enormous difficulty to adapt to climatic changes and many species will die out. The amount of water in the oceans will increase and the salt water percentage will rise, killing many species of fish and thus breaking the food chain of the entire planet. In some cases experts have stated that in recent decades the habitats of species have shifted many kilometres towards the North Pole and eggs are being laid almost five weeks earlier than before. The number of desert regions will increase because the rise in temperature will dry up and impoverish the earth.
The ozone is a vital gas for the life on the earth . In the stratosphere about 40 kilometeres from the earth’s surface this gas makes a protective shield that stops the ultraviolets rays. If there isn’t this shield the life on hearth can’t be possible . In the course of time was registered a depletion of this shield ; and if we don’t stop polluting that can cause: - the increase of skin cancers and of problems to the eyes; - the degrease of the harvestes; - damages to the ocean ecosystem.
The depletion of this shield was called “ozone hole”. The most dangerouse substances for the ozone hole are the substances whose contain atoms of chlorine or bromine because one atom of these two elements can destroy 30 000 molecules of ozone. So if we don’t stop polluting with these two elements the ozone hole will expand all over in the world.