Climate change is a global phenomenon, about which there are few doubts from a scientific point of view, but difficult to perceive in daily life. Furthermore, as it is a planetary problem and is conditioned by factors that seem beyond the reach of the common citizen, it is difficult to really get involved in the debates on how to face it and the problem is discussed from a distance. These conditions favor the consolidation of perceptions that have nothing to do with reality, but fit well with one's own ideological tendencies. We present some myths commonly wielded by deniers, but also others by those who admit the reality of warming, but ignore discussions about its effects.
The scientific consensus
97.1% of the studies on global warming published in the last 20 years conclude that it is real and point to humans as guilty. The compilation was made by a group of scientists in 2012 taking scientific articles on the subject published since 1991 in thousands of scientific journals. The results were published in Environmental Research Letters. Even former skeptics like Mariano Rajoy have accepted that warming is real. The pope, too.
The sun is not the cause
Some of those who question climate change affirm that the current trend is natural and that it is due to the change in the solar cycle, which would have increased the radiation of the star on Earth. However, measurements from satellites in Earth orbit since 1978 show that the amount of solar energy reaching the upper part of the atmosphere has not changed. The problem is that once it enters, due to the greenhouse effect of gases such as CO2, less and less leaves.
A hot past, but ...
The study of the millennial ice of the glaciers has made it possible to study the concentrations of carbon dioxide during the last 800,000 years and to estimate the temperatures of the remote past. This information shows that both the temperatures and the concentration of greenhouse gases have been higher in the past. However, what seems different is the rate of growth. During the last warming periods, the average temperature took 5,000 years to rise between four and seven degrees. In the last century alone it has risen almost one degree, 10 times faster.
Although that does not mean that there were no cyclones or torrential rains before, scientists are managing to associate extreme weather events with global warming. A report by the American Meteorological Society published this month has analyzed several of these events and has tried to distinguish which can be attributed to the global increase in temperatures and which cannot. The document states, for example, that the extreme winter rains of 2013 and 2014 in the United Kingdom were not related to warming, but a link was found with the heat wave of 2013 in Argentina, which climate change caused five times more likely.
More ice in Antarctica
That there is less and less ice in the Arctic has little discussion among scientists. The same is not the case with Antarctica where the issue is more complex. According to NASA, in December 2013, the sea ice surrounding the continent reached its greatest extent. This increase, however, does not imply that the consequences of warming are downplayed. Although there is still debate, some researchers have argued that the change in ocean currents and winds caused by global change has favored the formation of ice in Antarctica, but NASA believes that the general rise in temperatures will eventually affect it as well. This continent holds among its ice about 80% of the planet's fresh water, with an ice layer of 2,500 meters high on average.
Some countries such as Russia or Canada may benefit from the effects of climate change. The increase in temperature can make available to these countries natural resources blocked until now by ice or turn into fertile lands some that are not now due to the cold. However, other regions, such as southern Europe, would see droughts worsen. The consulting firm Mercer has carried out an analysis to estimate the economic effects according to the degrees that the temperature increases. As explained in a recent article in the Financial Times, returns on investment in infrastructure or agriculture in emerging markets could improve if warming is limited to 2 degrees until 2050, but they would decline in developed countries or smaller companies. Until then there would be losers and winners. But if the rise is four degrees, practically all investments would be harmed, with exceptions such as nuclear energy or renewables.