In the last and final part of the article, Kunal elucidates two other different truths about CO₂ and Climate Change. He tells us about far reaching consequences wherein four of the nine cognitive abilities are adversely affected by increased levels of CO₂.

In part I of the article, we established the first different truth, i.e. global warming is a topic of recent concern and has been built upon contributions of scientists, policy makers, and concerned public over a time period exceeding 150 years. In part II, we indulge into two additional different truths. Thus, the second different truth is concerned with the seemingly benign issue of semantics – whether to use global warming or climate change. The third truth is the one that has been the least discussed in both scientific and non-scientific media and is concerned with how high CO₂ levels in atmosphere could have direct impact on our physical growth and mental faculty.

(ii) Global Warming or Climate Change?

What’s in a name, you ask. It’s a lot, in this case. Ask yourself – what image gets conjured when you hear the phrase ‘global warming’? I’d bet that your mind is simply connecting the obvious meaning of the two words – global (as in across the globe) and with warming (as in the increase of temperature). Thus, global warming would imply an increase in the average temperature of Earth. According to NASA educational website [6], the first usage of the term global warming “was in a 1975 Science article by geochemist Wallace Broecker of Columbia University’s Lamont-Doherty Geological Observatory: “Climatic Change: Are We on the Brink of a Pronounced Global Warming?” Somehow, we chose to adopt the first two words of the title. i.e. “climatic change”. The reason many of us, now refrain from using the term ‘global warming’ is that the phrase masks many severe effects of the change in climate due to increased global temperature. One such effect is the change in precipitation patterns, which can result in drought and have large-scale loss of human life in relatively short time frame. Another effect of increased temperature is the melting of the Arctic and Antarctic ice sheets, which are predicted to increase the sea levels significantly, ever so slowly, but exodus of humans from many coastal regions of the world, are inevitable. Bangladesh is one such country that will be greatly impacted with rise in sea level. Other effects of a warm Earth include changes in the incidence of floods (and drought) as well as tropical cyclones and storms; increase in ocean warming and its impact on ocean currents; absorption of more CO₂ leading to ocean acidification; melting of ice sheets and glaciers and changes in snow covers of mountains and in poles (Arctic and Antarctica).

Since, an increased global temperature caused by anthropogenic addition of CO₂ to the atmosphere has multiple effects, one must strive to use the phrase “Climate Change”, which conveys a much broader meaning to the phenomenon.

(iii) A Direct Impact of High Atmospheric CO₂ Level on Flora, Fauna & Humans

Earlier this year, in February, I was attending a talk by Prof. Don DePaolo of Berkeley Earth and Environmental Sciences. Amongst his various research interest is the topic of underground storage of CO₂, which could be one of the possible approaches to curb CO₂ levels in the atmosphere. In any case, while most of us are concerned with weather forecast for the day or week, and some of us are interested in looking at temperature trends over the past 150 years, this geochemist was presenting how Earth’s atmosphere and temperature may have been tens and hundreds of millions of years ago. He presented in great depth, the current understanding of Earth’s carbon cycle but what piqued my interest was this slide where he talked about “Paleocene/Eocene Temperature Maximum” or the acronym PETM as it is commonly referred to in that scientific community. This phenomenon existed around 55 million years ago – about 10 millions years after dinosaurs had gone extinct. There are many interesting aspects of the PETM, wherein Earth’s temperature rose by 5-6 ºC over a geologically short time period of 20,000 years. Recall, that our current concerns of increasing CO₂ levels and climate change and the associated global efforts to minimise the impact is to limit the temperature increase to less than 2 degrees. In any case, at the end of the talk, I asked him this question, “If the Earth has previously seen such a dramatic increase in the temperature and the flora and fauna largely survived, why we are concerned so much?” He smiled and gave a facetious response, “Look, I don’t know what the impact on life will be but likely we humans will be dumber”. Later that evening, I had the privilege to have dinner with him and I probed him further and he said we must examine the effect of higher CO₂ concentrations on our functioning. My obsession took over and after I returned home that night, I spent a few hours reading more about PETM and what impact it had on life. I also searched if there were studies on the effect of high CO₂ levels on humans.

I found a few studies on the impact of PETM on life forms at the time. Both flora and fauna were affected but only little is known as of yet. Discovery of fossils of two now extinct species – Ectocion and Copeciondavisi in the North American landmass (Wyoming) indicated that these mammals had smaller size that era preceding and one following after [7]. That is, high CO₂ levels are correlated with dwarfism in these species. Can we extrapolate the same effect for humans and other animals, if the CO₂ level were to rise? My answer would be – No, we do not have sufficient information but the scientists must start having a serious discussion on this so-far-neglected aspect of high CO₂ levels.

I also found a groundbreaking joint study by Harvard and Berkeley that was released in late 2015 regarding the effect of high CO₂ on human cognitive abilities [8]. Although the study discussed the results in context of indoor air quality and emphasised the need for good ventilation for buildings, the implications of high CO₂ level in the atmosphere has truly stirred my interest in this less-talked- about tale of the source of climate change. Nine cognitive functions were evaluated in this study and one set of data for how four of the nine key cognitive functions are affected by increase in _CO2 levels is shown in Figure 4.

What is clear from the results of the study is that if the CO₂ levels in the air that we breathe doubles, our ability for the following functions – to use information, to apply strategies, and for basic cognitive functions can drop by 50-60 percent. The data for crisis management is more scattered, it indicates that some will maintain or even increase their ability for crisis management – perhaps our instincts for survival kicks in – whereas other’s ability for crisis management will be impaired. These results are only for humans who were subjected to a short-term exposure of enhanced levels of CO₂. How will we respond, behave, evolve when exposed continuously to high levels of CO₂ in the air we breathe remains unclear.

Final Thoughts

As is the nature of science, ideas and theories are built and refined bit by bit – through evidence-based strengthening of propositions and, if need be, annulment of some. There is no debate about the radiation-absorbing properties of CO₂. The link between warming of Earth and increased CO₂ levels is becoming increasingly un-refutable. That the increased level of CO₂ in the atmosphere is anthropogenic in nature is also established now. The real unknowns are how rapidly will the climate change and what exactly will be the magnitude of the climate change impact. The rise in sea levels will be gradual and we may be able to move and migrate. Rapid migration away from drought-prone and flood-prone regions is feasible even if it is not ideal. After all, war has displaced millions in a short-time frame. How will we cope up with a constant high level of CO₂ level in the air is the question that is something I am wondering more and more about. We could imagine a world, where all the buildings take in the air and process it to reduce the CO₂ – much like moisture is condensed out during air-conditioning (Ah, and you thought air conditioning is about air cooling only… well, the word ‘conditioning’ refers to altering/conditioning the humidity of the air and in the process, the air is cooled as well… more on this topic some other time). That addresses the air quality inside. For outside excursions, perhaps a mask would suffice….I really hope we can curb the emission problems rather than live like an alien in our planetary home.

Reference:

[6] http://www.nasa.gov/topics/earth/features/climate_by_any_other_name.html; last accessed 09 April,       2016

[7] Philip D. Gingerich,Geological Society of America Special Paper 369, 2003 Mammalian responses to             climate change at the Paleocene-Eocene boundary: Polecat Bench record in the northern Bighorn Basin,       Wyoming.

[8] Joseph G. Allen, Piers MacNaughton, Usha Satish, Suresh Santanam, Jose Vallarino, John D. Spengler;         “Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic                 Compound Exposures in Office Workers: A Controlled Exposure Study of Green and Conventional                 Office Environments,” Environmental Health Perspectives, October 26, 2015, doi: 10.1289/ehp.1510037

Pix sourced by Author from Net

Feature Pic : “World In Fire Stock Photo” Photo by Danilo Rizzuti. Published on 03 August 2010 Stock photo – Image ID: 10019458

Kunal Karan

Kunal aka KK has B.Tech, MSc and PhD in Chemical Engineering. He is Professor of Chemical Engineering at a Canadian University. Environmental concerns have motivated his research, which is focused on next-generation clean energy technologies, viz., fuel cells and batteries. He has published over 70 peer-reviewed research articles in international journals and given numerous talks across the globe. He fills up his research-free time experimenting with photography and casual writings.

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