This is the third and final article in my series of three principles for thinking about climate change (you can find links to the previous two at the bottom of this article). I have deliberately made these articles as simple as possible. There is no shortage of incredible content (including powerful visuals) available on the internet provided by climate scientists for those who wish to learn more. After this I will be moving on to consider local, regional and national consequences and what responses are available to us, as well as how climate change is an excellent way to think about other signs of decay in our society.
In the last article, I talked about the certainty of the basic mechanisms and consequences of rapidly changing the climate, even while acknowledging that specific events can rarely be predicted with any certainty. This is like knowing that you have a leaking head gasket, knowing what the eventual result will be, but not knowing exactly when it will happen.
This brings me to the last principle, which is the most important for understanding why we’re already in an emergency.
3) Understanding why climate change is dangerous requires thinking in terms of delayed consequences.
It’s a cold Wawa night and you jump quickly into bed so you can get underneath the blankets. But you’re still cold, so you add a couple of extra ones on top. A short while later you wake up drenched in sweat. There was a lag in the time from when you put the blankets on until their full effect was felt. Now imagine that you could not remove any of the blankets!
You can think of the climate as a system of interacting machines full of moving parts, where some parts respond immediately if you make a modification, while other parts of the system do not show changes for some time.
Again, many of the mechanisms involved are ones that we are all familiar with, even if we have not thought much about them. Anyone who enjoys swimming in lakes knows that water warms (and cools) slower than the air, which is why swimming around Wawa is much more pleasant in August than in June, even if the air temperature is the same.
The earth’s surface is mostly water, and a lot of that water is very deep. A lot of the extra energy trapped by greenhouse gases goes into warming the water. While the earth as a whole has warmed approximately 1.2 degrees Celsius since pre-industrial, that is an average that includes oceans and land. Taken on their own, temperatures over land have increased by about 2 degrees Celsius.
While it takes more energy to warm water than air (or land), it takes even more energy to melt ice. To be specific, it takes over 4 times as much energy to melt 1kg of ice at 0 degrees Celsius, as it does to raise the temperature of that 1kg of water from 0 degrees to 20 degrees Celsius. That is one reason why what is happening to Arctic sea ice is so important. As the ice disappears not only is less sunlight reflected away from the earth by the ice, there is less energy going into melting ice, and more into warming water, air and land.
Because of all these moving parts, it is hard to give an exact timeframe for how long it takes for the full effect of carbon dioxide (CO2) and other greenhouse gas emissions to be felt. Depending on how many of these effects are taken into account, the science tells us that delays in maximum warming from CO2 emissions are 10 to 40 years.
This is very bad news. While the effects of climate breakdown are now beginning to make themselves known at a scale that makes them difficult to ignore, we already have significant debt —in terms of past emissions —that remain to be paid.
If you are 10 years old (the short end for maximum effects of emissions to be felt), over 20% of CO2 emitted since the beginning of the industrial era have occurred in your life time. That means we have not begun to deal with the consequences of 1/5th of all emissions we’ve already put into the atmosphere.
If we take the 40 year time period, which includes some of the slower responses, it turns out that 65% of global emissions of CO2 have occurred over the last 40 years.
More than 30 years after the first international agreements on climate change, we are emitting more CO2, more methane (CH4), and more nitrous oxide (N20), per year than we ever have. Temperature rise is accelerating, as is the growth rate of CO2 in the atmosphere.
Our approach to the problem has clearly failed. Meanwhile some oil companies, and those with economic interests in the industry, continue to fund campaigns of obfuscation designed to confuse, mislead and prevent the sort of collaborative action that is required to face this crisis. Canada continues to provide large subsidies to these industries.
If we now try to synthesize the three principles I have written about we should understand that we are in an emergency. While the recent effects of climate change in Wawa have included cooler winters and springs than in recent memory, looking at the rest of the world we see that this year in Alaska all of the spring temperature records were shattered, and that the Arctic just had its warmest May ever. We see that Alberta and BC are dealing with more massive fires early in the year, that there is record flooding in the U.S., and that extreme weather events are happening more and more, as insurance companies well understand.
Moreover, even though many people knew we could expect such things to happen for decades, we have been unable to slow our global emissions. Finally, we know that what we are seeing now is only the beginning of what we’ve already set in motion. We know, for example, that the West Antarctic Ice Sheet will collapse no matter what we now do, and that there will be devastating consequences from sea level rise, including in the Maritimes; it is only a question now of how fast it will occur.
Ecology teaches us that when coyote populations have grown in response to an abundance of snowshoe hares, the coyotes still believe (if you’ll grant me the personification) that they are in a Golden Age for sometime after the hare population has begun to collapse. That is the consequence of a lag within the system, the same sort of lag we find throughout the earth’s systems. We have been living in a dream, as though we have multiple Earths to support us. The alarm bells are ringing, and have been ringing for sometime. The longer we wait to wake up, the more rude our awakening will be.
I am not a climatologist. In some ways that gives me freedom to speak frankly. Globally, we have already entered a time of great tribulation and calamity, and it is quite possible that it is already too late to avoid catastrophic warming. We are in the early stages of a global migration crisis that will see at least hundreds of millions of people on the move before the end of this century. We are in a global extinction crisis, where 25% of known species are currently at risk of extinction. How will our public institutions respond? That largely depends upon how we respond.
My next few articles will get into some more specifics and focus on our ways we might respond, from the national level to the local. While I have more questions than answers, I am confident that there is no more important conversation to be having.