Climate change
This topic deals with its causes, symptoms and consequences for nature and people
Effects of climate change I
"Our biggest problem is that we can no longer imagine what we do.“ Anders, Gunther; Philosopher
First it should be mentioned that the climate always responds to external influences with a certain time lag. Climate researchers assume that the responses of the climate system to our actions will not be observable to their full extent until 2050. The consequences of climate change interact with one another, form a global network and are also felt around the world. As such, local loss of crops for example, can have effects such as global changes in prices, quality and availability.
Find out which manifestations of climate change are being referred to in the various descriptions. You will also receive information about what impacts these manifestations have.
Worldwide I am retreating and becoming thinner. In the northern hemisphere, I have shrunk by 10% since 1960. I am, in addition to the thermal expansion of sea water, also part of the reason that sea level has risen by 10-20cm in the 20th century. Through me the Antarctic is darker and therefore heats up even faster. My decline threatens the existence of polar bears, because they depend on me while hunting. In the long run my retreat could threaten many river basins, which I still feed.
Correct answer: a reduction in ice and snow
Considered over a longer time scale I do not appear more frequently, but rather more intensely. Due to global warming, on the one hand there is more water vapour in the atmosphere, on the other hand, more water vapour is transported from the oceans to the continents and therefore I appear increasingly in inland areas. I vary greatly regionally, in the tropics and high latitudes I appear frequently, in the subtropics, however, rarely. I also appear a different number of times in the winter and summer months. So I am decreasing in the summer across Europe and in the winter, appear only in southern Europe. In addition to river regulation, dams, irrigation systems or changes in the land use in catchment areas I am partly responsible for flooding. Accordingly, I am, in addition to hurricanes and rising sea levels, also a threat to important monuments, archaeological sites and other physical remnants of history and cultural heritage. Floods also increase the risk of infection by diseases transmitted by water.
Correct answer: intense rainfall and following floods
Two thirds of the damage caused by natural disasters are caused by me and I cause destruction in rural areas especially. If I come over the Atlantic, I am called something different from when I come over the Indian and Pacific Oceans, even my precursors have a different name depending on their strength. In 2011 I struck more often than at any other time since measurements began in 1850, that is to say exactly 34 times. It is striking that the strongest of me have become more frequent in recent decades, at best I can be seen as an indication of the influence of man, because the natural fluctuations from decade to decade are very large. What is certain is that my frequency goes hand in hand with an increase in sea surface temperature, which in turn is due to both natural and anthropogenic causes.
Correct answer: intensification of tropical cyclones
On the one hand the Gulf Stream’s circulation affects me, on the other hand global warming. Because I am very large, my measurements vary depending on location, for example if I grow warmer in the northern hemisphere, I show no significant changes in the southern hemisphere. Climate models have, however, already explained this curiosity: first, there is less land there and secondly I mix vertically there. I encourage the spread of disease and parasites. For example, in 1990 thousands of dolphins died of an epidemic and the coral reefs are becoming increasingly pale because they are abandoned by the algae.
Correct answer: extreme temperatures
Due to the ocean currents I do not behave the same everywhere. Satellite measurements in recent years have shown that I have been consistently rising by 2.7mm per year. I could become one of humanity’s greatest problems as whole islands and coastal regions are endangered by me and therefore millions of people could become environmental refugees. Irrespective of this, 40% of the world’s population lives less than 100km from the coast. If all the mountain glaciers melted, I would rise around 0.5m. In the short term I vary partly due to wind or the tides, in the long run global warming also affects me, for example through the melting of the ice sheets in the Antarctic and Greenland as well as the melting of mountain glaciers. In addition I can change due to the rising or falling of the earth’s crust.
Correct answer: sea-level rise
I change the oceans as carbon dioxide behaves chemically actively in the water. The world’s oceans serve as a CO2 store. They hold 50 times more CO2 than the atmosphere, but the more CO2 there is in the atmosphere, the further this natural circulatory system is brought out of balance. As a consequence more CO2 finds its way into the upper layers of the ocean and eventually into its depths. I am caused by CO2 in the world’s oceans which dissolves and reduces the pH level of the water. This value has been sinking since the start of industrialisation. This effect on the chemical balance of the oceans also impacts on life and ecosystems there. As such I have, for example, an influence on chalk formation by groups of plankton, mussels, snails and coral as well as on their growth and reproduction.
Correct answer: acidification and warming of the oceans
Surface water evaporates faster due to me. This means first and foremost that the demand for water increases. In addition I cause snow and glaciers to melt more quickly. In effect I intensify water shortages in some areas and increase the risk of drought and forest fires. A lack of water, poor water quality, a lack of water for sewage and waste disposal as well as desertification impact the production of food and the spread of disease at the same time. In extreme cases I also change the habitats of many mammals, amphibians, birds and plant species, thereby destroying the ecosystem.
Correct answer: summer droughts
Sources
Schüppel, Katrin (2007): Klimawandel und Klimaschutz. Informationen, Hintergründe, Diskussionsanregungen. Mülheim/Ruhr: Verl. an der Ruhr
Wegner, Jochen (2013): Die Zeit.Wochenzeitung für Politik Wirtschaft Wissen und Kultur. Nr.24. Hamburg: EIT Verlag Gerd Bucerius GmbH & Co
Latif, Mojib (2007): Bringen wir das Klima aus dem Takt? Hintergründe und Prognosen. Frankfurt/M.: Fischer Taschenbuch
Dow, Kirstin/ Downing, Thomas E. (2007): Weltatlas des Klimawandels. Karten und Fakten zur globalen Erwärmung. Hamburg: Europäische Verlagsanstalt