In the previous articles I wrote about this subject, I’ve been exposing some data and facts that make me believe that global warming is true, although there are some groups of individuals claiming it is a hoax – “Global warming I: Is it true or is it a hoax?”. In my second article, “Global warming II: The polar ice caps and the sea”, I presented more concrete data regarding the thawing of the polar ice caps, the sea level rise and its acidification.
In this article I will talk about the theme’s controversy with the opposers claiming that global warming is a lie and a hoax.
It has been said that around 97% of the climate researchers around the world agree that human activity is causing the global warming. Just 3% state the opposite but it is with this apparent minority that the biggest controversies rise!
Some of the scientists of each part claim the other part is being supported by funds. The defenders of the global warming also allege that they are being put under pressure by politicians who want them to distort and hide results that suggest human activity is behind global warming.
The most daring accusation is from the defenders who claim that Exxon Mobil (US) is funding institutions where the sceptical voices against global warming emerge. According to some obtained documents, Exxon Mobil should have funding The Independent Institute with about $20,000 between 2002 and 2003. Later on 2003, this organization released a study claiming that the evidence of imminent global warming, found during the Clinton administration, was based in “bad science”.
And this shouldn’t have been the only consortium of sceptics to have been funded by Exxon Mobil. The George C. Marshall Institute would have received around $630,000 in funding for climate change researches between 1998 and 2005 and more $472,000 were used to fund The Board of Academic and Scientific Advisors for the Committee for a Constructive Tomorrow, also between 1998 and 2005. Curiously, or not, the well known as the “god father” of the climate change sceptics, Dr. Frederick Seitz, served as both Chairman Emeritus of The George C. Marshall Institute and a board member of the Committee for a Constructive Tomorrow from 1998 to 2005…
But what are the basis used by sceptics of global warming to oppose most of the defenders?
The percentage of CO2 in Earth’s atmosphere is insignificant:
The percentage of carbon dioxide in Earth’s atmosphere is insignificant comparing to other greenhouse gases, sceptics say. In fact, when we talk about “ppm”, we are talking about “parts per million”. In the composition of the atmosphere, CO2 appears with a concentration of only around 0,04%, which comparing to the almost 78% of nitrogen and 20% of oxygen, is really a very small amount.
But it’s also important to know that regarding to greenhouse gases themselves, carbon dioxide plays a role of 9 to 26%, water vapour 36 to 70%, methane 4 to 9% and ozone 3 to 7%. Sceptics say that the contribution of carbon dioxide from human activities is just around 1%.
It’s also said that in the past our planet had much greater concentrations of carbon dioxide and even so, some glaciations should have been observed. Studies show that in the Ordovician period of the Paleozoic Era (480 to 443 millions years ago) the concentration of CO2 was 4400ppm, 0.44% of the composition of the atmosphere, and there are signs of some possible glaciations.
Recent observations shows that an increase of warming is followed by an increase of CO2 levels with a 5 month delay. This time lag is being used by the sceptics to argue that that the current rise in CO2 is a result of warming and not a cause.
On the other hand, analysis of carbon isotopes in atmospheric CO2 shows that the recent rising of CO2 concentration cannot have come from the oceans, volcanoes, or the biosphere, which might prove that this rising is not related with the warming but with human activities as the defenders of the global warming say.
Global warming is being caused by natural causes:
Most of the sceptics argue that global warming is being caused by natural factors such as ocean currents, solar activity increases, solar winds and cosmic radiation.
Our Sun has periodical oscillations with activity peaks. Some studies show that current solar activity is being historically high by the observation of sunspot activities and other factors. Some say that solar activity for the last 60 to 70 years has reached the highest levels in 8 thousand years.
One big point of controversy between both parts – defenders and opposers – is in the correlation of temperature with solar variation. But it is a fact that Sun’s behaviour has direct and indirect influence on our planet, specially in the atmosphere, from the amount of cloud formation to lighting strikes. For example, a recent study even suggests that when Earth is hit by solar winds there’s an increase in the occurrence of lightning strikes.
There are also some that claim the rising of CO2 concentrations on the seas, and consequent acidification, is being caused by submarine volcano activity and not by human activities.
Regarding the rising of seas temperature, a study shows that 70% of the temperature rising in the Atlantic ocean is caused by a decrease of sand storms in Sara’s desert and the decrease of volcanic activity in the tropics. In this case, only 30% of the temperature rising is due to climatic changes. However, one of the researchers and main author of the study Amato Evan, a climatologist in the University of Wisconsin, does not depreciate the importance of climatic changes and says this particular fact might explain why the Atlantic ocean is warming faster than the Pacific.
Temperatures in the Antarctic:
The temperature records in the Antarctic is another hot issue that is bringing a lot of debates and controversies from both parts. While the IPCC claims that the overall temperatures are rising in that region, sceptical say that there are areas in the Antarctic where the inverse is being observed, meaning a decrease of temperature.
A 2011 study shows an average warming in the Antarctic in the last 30 years, thus favouring the IPCC arguments. On the other hand, a paper released on 2002 stated that some areas of the Antarctic have cooled between 1966 and 2000, specially during Summer and Autumn.
This data has being used by sceptics to create more arguments against global warming. However, the article’s author, Doran, claims a misinterpretation was made regarding the data, explaining that about 58% of the Antarctic cooled between 1966 and 2000 but the rest of the continent was warming in the same period. NASA data confirm this trend.
More controversy came up with a Michael Crichton’ novel, “State of Fear”, written in 2004, where a character says that only a small area of Antarctic, called the Antarctic Peninsula, was melting while the rest of the continent was cooling and the ice getting thicker.
Data interpretation and the scientific (“un”)consensus:
To get things more confused, there are several different interpretations of the data and even to possible consequences. From those who claim that there are no evidences of global warming at all to those who even argue that a rise of CO2 is beneficial, with positive consequences, we can also find different opinions even among the sceptics. In the last case, there are even those who claim that the rise of carbon dioxide will be good to the nature in general, which needs this gas in the photosynthesis process.
Many sceptics criticise the pessimist scenarios from the IPCC, and other organizations, claiming that the recorded data has not enough relevance to proof the global warming theory. Others also claim that the climatic models, created by the organizations that are in favour of the global warming theory, have no scientific bases to support such “alarmist” projections about future weather, criticizing the processes used in the models calculations.
On the other hand, from the activists defending global warming, there are those who say that the IPCC is hiding the true extension of the problem by issuing reports with conservative estimates because of political reasons, in order to secure the consensus among governmental representatives, and underestimating the pace of climate changes and respective effects on population.
The controversies spread while general public is being bombarded with hundreds of Youtube videos with people defending global warming and others claiming it is a hoax. The public opinion is getting more and more divided between the believers and the opposers and in a geographical level.
The following chart shows the percentage of positive answers to the question: “Temperature rise is part of global warming or climate change. Do you think rising temperatures are a result of human activities?”
But, in fact, what might awaits us in the future? There are several climate models and projections that are quite worrying, as I will describe in the next article – Global warming IV: The climate models and our future.