“The whole purpose of education is to turn mirrors into windows.” ~Sydney J. Harris
Wow, it’s disheartening to see how many people truly don’t understand climate change but still post comments on various websites. My last blog addressed the cover story in last week’s Maclean’s magazine, Canada’s national newsmagazine. The article, entitled “The Canadian WInter the Never Was” addressed the fact that this past winter was Canada’s warmest and driest in the last 65 years, suggesting global warming may well be real.
Not surprisingly, many responses to the article were posted online including some to an poll regarding what readers thought about the article and the facts behind it. It was amazing how many people think they understand the facts but don’t. I felt the need to clear up some of the most blatant errors and thought it might be useful to to address the more common mistakes here. Hopefully I can clarify some information for those who don’t believe the changes our planet is experiencing are related to human activities, or who simply don’t understand the facts:
1. Global warming is global, not regional; you can’t look to some warmer region here as proof of global warming in the same way you can’t look to some colder region there and claim it as evidence against. It’s the global temperature that’s increasing on average, so never mind what’s happening in someone’s backyard, because that just does’t matter. The Maclean’s article was interesting and provocative because it reflected changes seen across the country, not simply one little corner of it. Indeed, northern latitudes are predicted to be most susceptible to climate change. This fits with the observation that Canada’s average temperature has increased more than the global average. But a cold winter next year won’t be proof that global warming isn’t real. What one city, one province or state, one country or even one continent experiences doesn’t count as proof. It’s what the whole planet is experiencing.
2. Orbital tilt as some describe it—more properly referred to as orbital “forcings” which aren’t only “tilt” or axis, but also changes in obliquity and precession that our planet experiences—don’t explain what we’re observing either. They help explain previous ice ages; i.e. changes that took thousands of years to occur, but not those that take only a few decades, such as what we’re observing now.
3. The sun hasn’t been more active lately and can’t explain what we’re observing. In fact, the last sunspot cycle was the lowest in the last 200 years, reaching the lowest point in 2008-9 which has been described as a “deep solar minimum.” This is one of the reasons global warming has received more attention in the last 15 years—less solar output yet hotter temperatures than usual in spite of it. If the last sunspot cycle had been average or—I shudder to think—more active than usual, we’d be in much deeper trouble than we are at present. This recent solar minimum helps explain why temperatures were rather stable over the last decade rather than continuing to climb, something deniers and skeptics often refer to as evidence that climate models are wrong or that global warming isn’t real.
4. Carbon dioxide levels are only one thing that contributes to global temperature change. Other factors include:
a) Orbital forcings as described above, but these take millennia to manifest, not decades.
b) Increased particulate matter in the atmosphere such as volcanic activity which helps screen out the sun’s rays and cool the planet ( a cool 1991 after Mt. Pinatubo’s eruption in the Philiipines is a good example).
c) The higher the greenhouse gas levels, the higher the temperature because these effectively insulate the planet.
d) And the El-Nino Southern Oscillation plays a part although that’s still more regional than global.
The only observation that adequately explains a change in such a short time span as we’ve observed is the increase in greenhouse gas emissions from human activities such as combustion of fossil fuels, deforestation, and increasing agriculture. That’s why 98% of the world’s climate scientists say that the culprit is us.
It seems unfathomable to me that some can’t believe 7 billion people spewing 30 billion tons of carbon dioxide into the atmosphere every year isn’t going to cause a problem. Physics tells us these greenhouse gas molecules will absorb infrared radiation and trap heat. This is science people, not opinion.
Clearly we need to educate people better, but as long as there are those with loud voices who have a vested interest in sticking with business-as-usual, we’re not likely to change enough people’s minds. Daniel Patrick Moynihan stated it very eloquently: “You’re entitled to your own opinions, but you’re not entitled to your own facts.”
I’ve done my best to help by writing a book on the subject with the goal of explaining the facts so that those with an open mind can learn the truth for themselves. Now if we can only find more people with open minds…