The science that supporting global warming and climate change are under endless scrutiny by sceptics who blatantly promoting incorrect assertions without checking the facts. Many of them continue to publicly challenge and claiming that human activities are not to be blamed. Countless recent statements and reports by many prestigious world leading scientific bodies have suggested that warming of the Earth over last half-century has been caused largely by human activities such as usage of fossil fuels as the main sources of energy, changes in land use, agriculture and deforestation.
Positive and healthy debates are always welcome, which de facto keeps the science on its toes, but the combination of myths, common misconceptions and sceptic's incorrect assertions have created spheres of mistrust, ignorance and change of perception among general public who may or may not genuinely have the knowledge of Climate Change. Therefore, it’s not surprising when we hear that in the UK 14th November 2009 ).
To some extend public should not be blamed as the roots of climate change science recently have been shaken by the leaked emails which were shared by climate scientists from the University of East Anglia in the UK and Intergovernmental Panel on Climate Change (IPCC) 2007 report mistakenly claimed that all Himalayan glaciers could melt by 2030. Everyone thought that the leaked email was a part of conspiracy, which directly played into the hands of sceptics who always look for more ammunition to reload their guns of denial.
What follows is only (among many) a main list of myths, misperceptions and some incorrect statements, in addition with some brief correct scientific clarifications. It is claimed that anthropogenic (man-made) sources of CO2 are so tiny that they can't change climate, on the contrary volcanoes and other natural sources are producing more. According to the U.S. Geological Survey man made CO2 amounts to about 30 billion tons annually, which is more than 130 times as much as all the volcanoes produce. 95% of CO2 releases to the atmosphere are natural but these CO2 draws back to the nature by plant growth and absorption process by the oceans which ultimately off set the total amount but leaving behind the amount produced by humans. Many experimental measurements including carbon isotopes have shown that burning fossil-fuel and deforestation have been the primary reasons where atmospheric CO2 levels have risen 35% since 1832.
Ongoing sceptic arguments on whether CO2 levels are strongly related to global temperature rise have played upon people’s misunderstanding of the relationship between CO2 versus temperature. Of course there are cases when this up or down relationship hasn’t worked in perfect synchrony as CO2 is not the only factor that determines global temperature variation, hence sceptics quickly point to the period where CO2 went up but during the same period temperature remained unchanged or didn’t rise. Evidences from Antarctic ice cores have revealed the history of last 400000 years, where they show strong correlation between CO2 and temperature. Evidently they fall and rise together. Furthermore, when the ocean temperature rises it tends to release more CO2, which further help rising the temperature. Due to more temperature rise, consequently there would be further release of CO2; therefore CO2 appears to be both the cause and effect of further warming.
We can not expect scientists to invent miracles. It is virtually impracticable applying traditional science on the entire atmosphere where all the variables are unpredictable, keeping one variable constant to see the trends of other variables or even replicating the same experiment is not feasible. Critics always argue that scientific climate models are not reliable; they are not very good projecting the future climate change. Climate models are mathematically representation of interactions of processes that occur in the atmosphere, ocean, land, frozen surfaces of the earth and the sun. General Circulation Models or GCMs is the most advanced tool available so far which can simulate the global climatic changes in response to increased amount of green house gas concentration. Models have been verified with the past temperature variations and if they can predict past correctly then why it wouldn’t reasonably predict changes in the future.
No doubt those who has read ‘New Nasa Model: Doubled CO2 means just 1.64C warming’ – a piece written by Lewis Page on ‘The Register’ news site has perhaps been marvelled over not to fret about mere temperature rise. Lewis Page wrote ‘it now appears, however, that the previous/current state of climate science may simply have been wrong and that there’s really no need to get in an immediate flap. If Bounoua [Lahouari Bounoua of Nasa] and her colleagues are right, and CO2 levels keep on rising the way they have been lately (about 2ppm each year), we can go a couple of centuries without any dangerous warming.’
But Nasa’s research conclusion never said so. Out of three models, Nasa’s first simple control model suggests that a doubling of CO2 would lead to warming of around 1.94C. Researchers also stated that their control result was at the low end of a range of other models from 2C to 4.5C. The purpose of controlled model was to include evapotranspiration data and find out if there were any differences and it showed that warming dropped to 1.68C, with the difference 1.9.4C – 1.68C = 0.26C, but researchers never suggested any absolute conclusion on temperature. Lewis Page most likely took the value of the control model and subtracted the dropped temperature 0.26C (rounded figure 0.3) and wrote that we don’t have any problems with the temperature rise as it would be just 1.64C (Hadley in Guardian, 2010).
Based on another Nasa model Lewis Page combined doubling of CO2 concentration of 780ppm (today’s accepted figure 390ppm multiplied by 2) and growth rate of 2ppm/yr, which would take 195 years. Later he quoted we can go a couple of centuries without any dangerous warming. But the Nasa researcher’s actual figure was 700ppm, not 390 ppm or Lewis’s imaginary figure 780ppm. Considering 700ppm is more than 310ppm of today’s accepted figure, therefore it will take 155 years not 195 years (Hadley in Guardian, 2010).
Lewis Page’s conclusion at best one classic example where a myth has intentionally been created, at worst it has spread like virus through the internet and it is rightly the winner when people have experienced extreme cold and big snowfalls particularly in the northern hemisphere during the last winters. No one dares talk about global warming when there is such extreme cold weather and certainly for many big freezes have been further indication that the notion of climate change is all empty and exaggerated talk.
Plethora of similar myths, ambiguous challenges by sceptics and misunderstanding of core scientific knowledge by general public have polarised the climate change debates. The challenges as well as the success for international climate science community lies in transparency, accuracy, honesty and knowledge sharing, otherwise perpetuators will continue push frontier to the wrong end.
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