Scientists around the world continually warn for the risks of global warming and its causes, and blame mainly the human activity, which increased the carbon dioxide concentration in the atmosphere, for the climate changes. Although they are correct when mention the temperature rising in the last century they do not consider in their forecasts facts as the temperature growth rate, inexperience with long term climate systems and new coming technologies. Ponder these aspects is extremely important to not wrongly take decision that have economical effects.
According to IPCC (Intergovernmental Panel on Climate Change), the temperature on the earth will rise from 1.1 to 6.4°C during the XXI century if the human activity does not change. These rates are an absurd because during the last century the global surface temperature increased only 0.74°C and in the last 5 years the warming rate has been constant, which implies in a growth of 1.7°C for this century. Moreover, according to Tom Harris, CEO of Natural Resources Stewardship Project, the annual temperature has decreased between 1998 and 2007, in contrast to the carbon dioxide concentration which has increased 4%. In addition, there were two periods of warming in last century: from 1910 to 1945 and from 1970 lasting until now. If we compare these two periods the warming rate was statistically equal in both periods, remembering that the first period had less influence of human beings and more of sun’s temperature increasing. Thus, it is not possible to blame just the human activity for the warming; there must be other unknown climate factors.
It is fact that the earth temperature increases according to the dioxide carbon concentration rising, but it is not the only neither the main factor. Two Russian solar physicists, Galina Mashnich and Vladimir Bashkirtsev, have made a bet of $10,000 with the Britain climate expert James Annan that the earth will cool over the next decade. Corroborating to their argument that the global temperatures are driven more by changes in the sun’s activity than by the emission of greenhouse gases is the Medieval Warming Period: between the 10th and 14th centuries, the North Atlantic region faced a warmer climate, which was followed by a cooler period, named Little Ice Age. Hence, as we only have statistical information about climate since 1850 it is too ambitious to predict a century with only 150 years of sampling. It is necessary to analyze the long term.
The model used to estimate the earth’ surface temperature for the XXI century is based on our actual reality. It assumes that in 100 years we will be under the same technology existing today. This is meaningless, because it is notorious the evolution of industries technology in the last 50 years. The automobile industry is an example: since 70s they started to reduce their size due to new computer-based technologies. Another example is the possibility people have today to work at home due to the huge existing connectivity; this means less people using cars and polluting less. While new coming technologies are unpredictable, investments in developing new technologies must be carefully evaluated. The urgent need to find alternative energy sources has led to a lack of supply of corn and sugar around the world. The lands previously dedicated only to food, now it is also explored for ethanol, which generates a price increase at food market and impacts the economy. Thus, it must be seriously reevaluated the climate warming forecast, otherwise decisions will be taken in a haste, without estimating other impacts.
Considering all the exposed above, people must be more critical when talking about global warming. It doesn’t mean stopping all the actions taken to reduce the carbon dioxide emission, but to understand that there are other factors involved in global temperatures changes. If the week weather forecasts have accuracy of 70% for only the first three days, it is irrational to think that IPCC is right. Thus, the IPCC should not only revise their forecasts but also show people that there is a great margin for error, because it is a long term forecast and there is no solid statistical data to make inferences with high accuracy.


