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The Climate ProblemClimate change refers to a range of climatic and weather events, such as increased average temperatures, sea level rise and greater rates of ice melt in the polar caps and glaciers around the world. For most of human history and hundreds of millions of years before that, such changes were brought about independently of human action. However, there is a broad-based scientific consensus that since the 1960s, human activity has itself been causing changes in our climate. This has happened chiefly through the burning of fossil fuels, deforestation and other industrial activities which release carbon dioxide, methane and other gases into the atmosphere. Once there, these gases trap heat, causing a warming effect which is akin to how a greenhouse works – hence the name greenhouse gases.
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Why do we need to worry about it? |
There are two reasons for worrying about climate change.
First, because it’s not fair. This map is distorted to show which countries, historically speaking, are responsible for the greenhouse gas emissions in our atmosphere. This second map is distorted to show who is at the sharp end of current extreme weather events, such as droughts and floods. The increase in these is associated with human induced climate change and projected to get worse if we don’t reduce greenhouse gas emissions.
Second, climate change, in combination other harmful environmental problems resulting from dominant modes of economic growth and consumption, has the potential to turn the world into a much less liveable place for human beings. Such is our impact on the environment already that it is increasingly common to talk of the ‘Anthropocene’. This term refers to an era in which human activity determines prevailing global environmental conditions as much as, or more than, changes in the oceans or the atmosphere determined previous entire geological ages. Some scientists are warning that we may risk tipping ourselves out of the Holocene itself – a surprisingly climatically stable period over the last 10,000 years during which humans have thrived – and into conditions in which activities fundamental to how we organise our societies, such as agriculture, become much more difficult and even unviable. The figure below indicates the temperature variability of the last glacial cycle, over a period of 100,000 years, suggesting that some of the greatest social and technological achievements that we most value have been greatly helped by these stable climatic conditions. Leaving these conditions behind, such scientists suggest, is potentially a very risky business.
(Rockström, J., W. Steffen, K. Noone, Å. Persson, F. S. Chapin, III, E. Lambin, T. M. Lenton, M. Scheffer, C. Folke, H. Schellnhuber, B. Nykvist, C. A. De Wit, T. Hughes, S. van der Leeuw, H. Rodhe, S. Sörlin, P. K. Snyder, R. Costanza, U. Svedin, M. Falkenmark, L. Karlberg, R. W. Corell, V. J. Fabry, J. Hansen, B. Walker, D. Liverman, K. Richardson, P. Crutzen, and J. Foley. 2009. Planetary boundaries: exploring the safe operating space for humanity. Ecology and Society 14(2): 32. Freely available online: http://www.ecologyandsociety.org/vol14/iss2/art32/)
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