Living Green Living Well - Global Warming is NOT other people

Click here to read other recent entries

Flat

Global Warming is NOT other people

User: josh
Date: 3/12/2009 12:59 pm

Views: 708
Rating: 0

Its been said more than once, "It is difficult to get a man to understand something when his salary depends upon his not understanding it." So we should not be surprised when a small Alberta Daily prints an op-ed piece claiming global warming is caused by human and animal breath. To distract us from the ecological disaster of the oil economy, the proselytes of hydrocarbons will lay the blame on anything from killer house cats to smog emitting forests.

Still, I was surprised to see the article “Human, animal breath creates 50% of GHGs, pessimist warns” reprinted in the Winnipeg Free Press. My response letter has generated some interest. It is reprinted below:

Greenhouse nonsense. Re: Human, animal breath creates 50% of GHG, pessimist warns, March 9.

The notion that human or animal breath is a major contributor to greenhouse gas emissions is nonsense. There were just as many animals on the planet 10,000 years ago -- fewer humans, more mastodons. Still, there has been a 37 per cent increase in carbon dioxide in the air since the industrial revolution. This has nothing to do with the number of breathers on Earth. We only breathe in what the plants breathe out. What has changed is that now, with our automobiles and coal-fired electricity plants, we have found a way of releasing the huge stores of carbon from millennia past. Only a shift in the way we live can stem the rise in greenhouse gases, not a shift in the number of creatures living.

- Josh Brandon

If you don’t trust me on this point, the US Carbon Dioxide Information Analysis Center, a branch of the US Department of Energy, gives the following response on their FAQ page:

Q. Should we be concerned with human breathing as a source of CO2?

A. No. While people do exhale carbon dioxide (the rate is approximately 1 kg per day, and it depends strongly on the person's activity level), this carbon dioxide includes carbon that was originally taken out of the carbon dioxide in the air by plants through photosynthesis - whether you eat the plants directly or animals that eat the plants. Thus, there is a closed loop, with no net addition to the atmosphere.

Humans and all other animals break down carbon-based plants in combination with oxygen to produce carbon dioxide and water. Plants do the reverse, keeping the system in balance, with generally no net gain or loss either way.

In order for respiration to make a difference, we would need to not eat those plants, stop breathing, while at the same time managing sequester all that carbon by keeping the plants that we would have otherwise eaten stored safe away from insects, herbivores and the rest. Would we then (in exchange for the sacrifice of not eating or breathing) regain our privilege to bulldoze another six lanes of traffic down Route 90 for our expanded SUVs? Probably not. There are several ways of calculating human emissions from breathing, but none of the sources I looked at came close to a figure of 23% given in the Op-ed, mostly ranging between 5-12 %. There are certainly better ways of reducing our carbon footprint more dramatically than this!

Re: Global Warming is NOT other people

User: josh
Date: 3/27/2009 9:50 am

Views: 0
Rating: 0

University of Winnipeg Climatologist, Danny Blair had this response to the Winnipeg Free Press which the paper declined to publish. Blair's letter below clearly explains the connection between breathing in and breathing out, if that were not apparent.

9 March 2009

I take great exception to the way in which “Human, animal breath creates 50% of GHGs, pessimist warns” (WFP, 9 March 2009), reprinted from the Red Deer Advocate, misrepresented the thoughts of Dr. James Lovelock. It is true that the human population, now approaching 7 billion, collectively emits a very large amount of carbon dioxide, simply by breathing, and in particular by breathing out. So, too, do our herds of pets and farm animals. However, the article conveniently neglected to mention that the carbon dioxide that we breathe out is extracted from the air by other organisms that, effectively, breathe it in. The food we eat, to keep ourselves breathing in and out, is comprised of plants or plant-eating animals, and all of their tissues can be traced back to the photosynthetic process, in which carbon dioxide from the air is used by plants to produce carbohydrate-based tissues. Thus, the carbon dioxide that we breathe out is essentially balanced by the amount of carbon dioxide extracted from the atmosphere by the plants that we eat, directly or indirectly. Consequently, the net contribution of the human population’s metabolic activity to the amount of carbon dioxide in the atmosphere is essentially zero. Lovelock knows this better than most people on the planet; to insinuate that he has suggested that human and animal breathing contributes to the ongoing accumulation of greenhouse gases is absurd.

The provocative and overly dramatic title of the article in question is extremely misleading and is ostensibly meant to convince readers, whether in Alberta or elsewhere, that the planet’s global warming problem is not really very much related to, oh, the Alberta tar sands project, for example. Yes, the mass of the carbon dioxide added to the atmosphere by the breathing of humans and their animals every year may actually be about 50 percent of the mass of carbon dioxide emitted by planes, trains and automobiles (to name but a few sources), but the mass of carbon dioxide we emit when we breathe out is, and must be, balanced by our food intake.

The more important issue is that the carbon dioxide emitted to the atmosphere by those planes, trains and automobiles largely originates from fossil fuels which have long been buried in the ground. More to the point, the carbon from these sources, a good portion of which is used to grow and transport our food in very unsustainable ways, is being added to the atmosphere much faster than Lovelock’s Gaia can “breathe” it back in. The oceans, the forests and the extremely slow geologic cycle simply cannot inhale our collective industrial exhaust as fast as we have been releasing it into the atmosphere. Unfortunately, this has resulted in a very rapid rise in the strength of the greenhouse effect and is causing an alarming amount and rate of global heating, as Lovelock calls it. If we do not rapidly reduce our non-metabolic carbon dioxide emissions, I am afraid, really afraid, that Lovelock’s grim vision for humanity will come true.

Danny Blair
Professor in the Department of Geography
University of Winnipeg

Previous • Next •