“Stopping global warming” had no place in Presidential debate

Blog, Climate, Tom Harris

Logic defeats the climate scare

Sometimes logic trumps even the loudest voices. That is what happened on Wednesday night when climate change and greenhouse gas emission reduction were completely missing from the first Presidential debate.

Nine climate activist groups—the League of Conservation Voters, the Environmental Defense Fund, the Sierra Club, the National Wildlife Federation, The Climate Reality Project, MomsRising.org, GlobalSolutions.org, iMatter Campaign and Moms Clean Air Force—delivered petitions with over 160,000 signatures to the office of debate moderator PBS newsman Jim Lehrer urging him to ask the candidates about climate change. For weeks, main stream media have been pushing climate change, asserting that President Obama and Governor Romney must address this, “the most crucial issue of our time.”

But they did not, and Lehr completely ignored the topic as well.

It appears that Obama, Romney and Lehr all instinctively understood that, in comparison with the nation’s pressing issues, discussions about “stopping global warming” were not worth even a single minute of air time.

Properly addressing climate change requires an understanding of advanced science, economics, engineering and policy issues, something most people do not have. But a simple exercise in logic shows that Wednesday’s debate participants were right to ignore climate change.

The approach involves estimating, in some instances guessing, the likelihood of an affirmative answer to a number of simple, but crucially important, questions. The questions are chosen such that a “yes” answer, or at least a high probability of the answer being in the affirmative, is needed in each case for there to be a high net likelihood that costly greenhouse gas (GHG) emission reduction policies are worth implementing.

Note: Not counting  water vapour (the most abundant GHG in the atmosphere), 85% of all human emissions of GHG in developed countries such as Canada and the U.S. is carbon dioxide (CO2). Not surprisingly, most climate mitigation policies (mistakenly) address CO2 emissions. Therefore, the questions below are asked in terms of CO2, not GHG, emission reduction.

Since this summer’s supposedly record low level of Arctic sea ice has been regularly cited by activists as “proof” that severe CO2 reductions are urgently needed, let’s use that as a test case to see if that argument is logically tenable. This general method can also be used to assess the veracity of other “proofs” that we need to reduce CO2 emissions—atmospheric temperature change, sea level change, trends in the incidence and severity of extreme weather events, etc. The questions would be different, but the method is the same.

So, here are typical questions one needs to ask about the connection between Arctic sea ice extent and the necessity of severe CO2 reduction actions. Throughout, I cite the assessment of leading historical climatologist Dr. Tim Ball, former climatology professor, University of Winnipeg, and an advisor to the Frontier Centre for Public Policy.

Question #1: Was last month’s Arctic sea ice extent unusual?

Scientists who study long term climate change tell us that there have been many times in Earth’s past when the Arctic was mostly, or completely, free of sea ice. As recent as the 1930s, it is believed the Arctic was warmer than today and so would almost certainly have had less sea ice than in 2012. We don’t know for sure, of course, since satellite sea ice monitoring only started in 1980 but Dr. Ball and many other experts would say that the likelihood of this question having a “yes” answer is essentially zero. Dr. Ball points out that this summer’s minimum sea ice extent as calculated by different groups varied by as much as 30%, even though each were using the same raw data set.

But, for the sake of this analysis, let’s be generous to climate campaigners and say the probability is 50%.

Question #2: Assuming the ice extent was unusual, is it dangerous?

As before, Dr. Ball and many scientists would assign a probability of an affirmative answer to this question at zero since both human society and nature (including polar bears, which obviously survived warmer periods in the past) are not dangerously affected by low extents of sea ice in the short term. In the longer term, some scientists assert that a significant reduction in Arctic sea ice will amplify global warming since less incident sunlight will be reflected back into space by the relatively bright ice (the ocean, being darker, absorbs most of the incident sunlight). However, since Antarctic sea ice set a record high this year (see here) and generally offsets the drop in Arctic sea ice each year (see here), net global sea ice is not known to be changing significantly (see here).

However, for this discussion let’s assign (unrealistically high) 50-50 odds to the likelihood that the answer to question #2 is yes. Since one multiplies individual probabilities to determine the overall likelihood of a specific event occurring, we are now down to a 25% (i.e., 50% times 50%) chance that Arctic sea ice extent this year was both unusual and dangerous.

Question #3: Assuming the low sea ice extent is unusual, and dangerous, is it due primarily to atmospheric warming?

Sea ice coverage is not just a function of air temperature. Winds, cloudiness, precipitation, particulate pollution levels, ocean currents and ocean temperature play important roles as well. In fact, Arctic air temperature was lower in the summer of 2012 than in 2007, even though sea ice extent was supposedly lower this year than in 2007. This year’s change was primarily due to a storm in the region causing stronger than usual winds that broke up the sea ice, leading to accelerated melting (note: the change in sea ice cover between 2007 and 2012 was actually less than the uncertainty in the measurement so, statistically speaking, there was no different in sea ice coverage between the two years).

Dr. Ball assigns a 0% probability that “yes” is the correct answer to this question as well. Some other scientists say that warming does play a large role in summer sea ice extent in the Arctic. So, while warming was clearly not the major factor in setting a record this year, we could perhaps assign a probability of “yes” being the correct answer to question #3 as, say, 50%.

But, let’s be generous to climate campaigners again and give it, 90% odds. Despite these unrealistic assumptions, we are now down to a 22.5% chance that it is worth enabling extreme CO2 controls.

Question #4: Assuming the low sea ice extent is unusual, dangerous, and due to atmospheric warming, is the warming primarily due to an increase in CO2?

There is intense debate in the climate science community about this question. Are variations in the output of the sun the major driver of recent climate change? Is it ocean currents? Is it CO2 emissions. No one knows for sure.

Dr. Ball assigns the probability of this question as having a yes answer at 0%. Other scientists give it a higher value, although no one who understands the field would give it 100%.

For the sake of this analysis, let’s give it 50-50 odds. We are now at an 11.25% chance that low sea ice extent is unusual, dangerous, and due to atmospheric warming caused by an increase of CO2.

Question #5: Assuming the ice melt is unusual, dangerous and due to atmospheric warming caused by CO2, is the major part of that CO2 rise due to human activity?

The main source of CO2 emissions are the oceans. It takes only a tiny rise in ocean temperature for massive quantities of the gas to be released. Of course, oceans have always warmed and cooled for entirely natural reasons so the change in CO2 levels in the atmosphere could be essentially all due to natural factors.

Dr. Ball says that there is a 0% chance that yes is known to be the correct answer to question #5. He points out that the estimated magnitude of humankind’s total emissions is significantly less that the uncertainty in the measure of atmospheric CO2 quantities.

But, again, let’s give it 50-50 odds and see where this gets us. We are now down to a 5.6% chance that low sea ice extent is unusual, dangerous, and due to atmospheric warming caused by an increase of CO2 primarily because of human emissions.

Question #6: Assuming the ice melt is unusual, dangerous, due to atmospheric warming caused by human CO2 emissions, is it more effective to reduce CO2 emissions or to prepare for and, later, adapt to the sea ice melt and other climate change?

Dr. Ball explains that the uncertainties in ascertaining an answer to this question are so high that he will not assign a probability to a yes answer at all. However, to complete our analysis, let’s give it 50-50 odds. We are now down to about a 2.8% chance that it is worth enabling extreme CO2 controls as a result of events in the Arctic.

In other words, even with unrealistically high probabilities that we have chosen that the correct answer to each of the above questions is yes, it is more than 97% likely that it is not worth enabling extreme CO2 controls because of the sea ice argument.

To end up with an overall probability of a paltry 50% that it is worth enabling the sorts of emission controls that David Suzuki and Al Gore advocate, one would need to answer “yes”, with an average likelihood of 90% that that is the correct answer, to every one of the above six questions. It seems inconceivable that anyone, even Suzuki or Gore, would do that.

Precisely the same sort of logical analysis may be performed, with similar results, on other evidence supposedly supporting the need for severe CO2 controls (some of which are, as mentioned previously, atmospheric temperature change, sea level change, trends in the incidence and severity of extreme weather events, etc.).

“Oh dear,” responds the climate scare, “I hadn’t thought of all this”, and promptly disappears in a puff of logic.

Clearly, climate activists who want us to pay a king’s ransom to reduce CO2 emissions have not examined the issue in a systematic, logical fashion. Most true believers seem prepared to make huge leaps in faith from answering “yes” to one or more of the questions one need address to sensibly consider the issue to the conclusion that severe emission reductions are urgently required. That is irrational, no matter what you believe about the science.

Of course, logic rarely plays much of a role in partisan and emotionally charged issues such as climate change. With Gore’s intense multi-media event “24 Hours of Reality: The Dirty Weather Report” only 5 weeks away, this week’s brief recess from climate hysteria will probably be short lived. But, it was nice while it lasted.
Tom Harris is Executive Director of the International Climate Science Coalition and an advisor to the Frontier Centre for Public Policy.