global warming — English

A general increase in global temperatures over periods of at least several decades believed to be caused by increased levels of so-called “greenhouse gasses” (such as CO2, CO and methane [CH4]) released into the atmosphere by human activities. These gases “trap” the longwave radiation from the Earth to the atmosphere and, therefore, the Earth-atmosphere system retains more of the heat energy than it would if the greenhouse gasses were absent. The theory holds that the global climate is changing at an unusually fast rate and warmer climatic conditions now prevail all over the Earth than did a hundred years ago. This does not mean that the everyday atmospheric temperature all over the Earth is notable higher than it was 50 to 100 years ago, so proving this is a difficult task and since there are always abnormally cold winters to disprove the theory (an example is the exceptionally cold winters of 2010-2011 and 2012-2013 in both Europe and North America). However, the average temperatures over the past 30 or so years seem to be higher than a 100 years ago. This slow warming of the climate is largely blamed on the anthropogenic (human-made) actions such as releasing large volumes of carbon-rich compounds into the atmosphere (see “air pollution”), but proving these assumptions is extremely difficult and many people remain unconvinced. Global climate is undoubtedly changing, but that is a normal process which had been happening repetitively (actually continuously) for thousands of years. In fact, the composition of the Earth’s atmosphere has continuously been changing ever since the creation of the Earth some 4 500 million years ago. The current phase of warming is often ascribed to human activities that cause atmospheric pollution as a result of the combustion of fossil fuels, but many creditable scientists believe that human actions have a very small to negligible effect compared to what nature itself is doing. Statistics irrefutably show that the CO2 (carbon dioxide) concentration in the atmosphere has increased by approximately 15% since 1890 and the Earth’s temperature has increased by 0,5˚C during the twentieth century, but the cause is by no means certain. Owing to industrial development, enormous volumes of greenhouse gasses have been released into the atmosphere since about 1850. The question is whether this caused the higher temperatures now being recorded. In other words, are human activities responsible for the recorded warming of the atmosphere? We cannot prove it, but we make the assumption that they are. Since global warming could have many serious impacts on human life on Earth, we take the notion of global warming seriously enough to hold one international conference after the other in order to curb the release of greenhouse gasses, but little success has yet been achieved.

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