You can't do science with politics. Razors cannot slice glue. Science is a razor. Politics is glue. Everything, no matter how sharp, gets stuck in it.
The "climate change debate" illustrates the problem. There's really no debate about what we need to do. We got past that last December in Paris where it was agreed, much belatedly, that our "never exceed" temperature limit had to be 1.5C. That's 1.5 degrees Celsius above pre-industrial levels. Anything beyond that invites, perhaps even ensures, climatic calamity.
1.5C it is then.
Everyone came away from Paris patting themselves on the back. Not sure why. What they left in Paris were national commitments, promises, by each nation of the cuts in greenhouse gas emissions it was willing to implement by specified dates. Such and such a percent by such and such year.
Unfortunately, when you add up all those promised cuts what you're left with is 3.5 degrees Celsius of warming and not to put too fine a point on it but that's not survivable for most life on Earth, including you and me and our kids and theirs.
The problem with a political approach to climate change is that it gets bogged down with man-made (anthropogenic) global warming. It's as though we're the only players at the table. That 1.5C is for us. We don't have to share it. That ignores who else is sitting at the table - nature.
Nature, represented by physics, geology, chemistry, hydrology, biology, zoology, botany, meteorology, glaciology, atmospherics, and every other Earth science, also has a handful of cards and that hand is also in play.
We don't know how Nature will play its hand. We do know that it's upping the ante.
That 1.5C goal reached at Paris? There's a hitch. We're already there. We've already loaded the atmosphere with enough man-made greenhouse gas that we've locked in 1.5C of overall warming. Every fossil-fuel generating station, every wildfire, every tank of SUV juice, every truckload of cement - that's all atop the existing 1.5C loading. Congratulations. We've set ourselves an ambitious target we have already exceeded.
Don't worry, we're working on a plan and it's going to be a dandy. We'll have carbon taxes even as we ramp up the extraction and export of bitumen to world markets. Oh yeah, and we're still selling coal to boot.
But what about Nature? Well, what about it? The 1.5C target? That's all about preventing catastrophic, runaway climate change. What does "runaway climate change" mean? It means Nature, natural processes that we cannot control that will overheat the Earth. Science tells us these natural impacts can eclipse anything man-made.
Well, we're at 1.5C or we soon will be so what then? The mechanism of runaway global warming is thought to involve triggers known as "tipping points" that, when reached, will activate "natural feedback loops" that are unstoppable. Our best guess is that those tipping points will be passed at 1.5C of man-made global warming or at least that's the political narrative.
When this whole scenario was first floated (not all that long ago) it imagined the Arctic being ice free - by about the year 2100. No one imagined it could happen by 2016, more than 80-years sooner than anticipated. Oopsie!
So, what happened? Natural feedback loops, that's what happened. The Arctic warmed, sea ice thinned and then disappeared. In place of that white, reflective ice cover that once bounced solar radiation safely back into space, dark green ocean water began absorbing that solar energy, heat. The Arctic Ocean got warmer and it warmed the atmosphere above it and that set a whole bunch of wheels in motion.
There are knock-on effects, one feedback loop triggering others. As the Arctic warmed, boulders of frozen methane, "clathrates" a.k.a. "fire ice,"
lining the ocean floor and many lakes began thawing, releasing plumes of methane gas to the surface and upwards into the atmosphere. Methane is a more powerful greenhouse gas than CO2. It's not as long-lasting as carbon dioxide but it's persistent enough (about 12-years) to do a lot of damage.
Much of the terrestrial Arctic is comprised either of exposed rock or tundra, which is basically ancient peat. Peat, of course, is rich in hydrocarbons and makes a dandy fuel, ask any Irishman. Until now most of the CO2 held in the tundra has been safely sequestered by cold temperatures. However the warmer Arctic temperatures have been causing the tundra to dry out which transforms it into dandy fuel for wildfires. As you might imagine, we don't have much firefighting capacity in the Arctic, no way to extinguish tundra fires.
A tundra fire has three knock-on effects. The combustion releases CO2 to the atmosphere. The fires also produce "black soot" that is blanketing the surface, absorbing heat to speed up the melting of snow and ice. This is a big problem for the Greenland ice sheet, accelerating the melting which contributes to sea level rise around the planet. The third, knock-on effect is that, as the tundra burns, it exposes the layer beneath it, the permafrost. That is a huge methane trap. As it becomes the perma-no-more-frost, as it thaws, that methane is also released to the atmosphere.
So there you have a neat little bag of feedback loops. If you reverse engineer it, the existence of feedback loops evidences tipping points that were passed some time ago. There may be other, perhaps slower onset feedback loops that haven't come to our attention yet.
Two that are in evidence are the retreat of glaciers and the broken hydrological cycle. We have warmed the atmosphere. 15 of the 16 hottest years on record have occurred during this century. Heat melts glaciers. It also causes physical changes in the atmosphere.
A warmer atmosphere is capable of holding more water vapour, a lot more as it turns out. That disrupts the hydrological cycle. Surface water is released to the atmosphere as water vapour through evaporation, perspiration and respiration by animals, and by plants through transpiration. It goes up into the air, condenses into clouds and then into rain and falls back to the surface where, among other things, it gives agriculture the water needed to grow our crops.
Once you have a warmer, wetter atmosphere it changes things. More water retained in the atmosphere means less water on the surface. This new reality contributes to precipitation changes. A warmer, wetter atmosphere is a more powerful atmosphere capable of triggering severe storm events of increasing frequency, intensity and duration. Bummer. Gives new meaning to "it never rains but it pours." Some places get sustained and severe drought. Other places get increasing precipitation, sometimes floods (thinking of you, Calgary). Some places get cyclical droughts and floods which, due to the soil compacting of drought can lead to destructive flash flooding. Double bummer.
Today's broken hydrological cycle can play utter hell on one of our most important carbon sinks, our forests. Trees absorb a lot of CO2 as they grow. Even when they die they can rot and create humus for the soil, another form of CO2 that nurtures microbial growth - the "circle of life" thing. What keeps that all going is rain, precipitation.
Drought causes trees to dry out, even die off, which transforms the forest from immensely valuable carbon sink into disastrous carbon bomb. As the forest dries out it becomes fuel for wildfires (thinking of you, Fort Mac). These fires are also increasing in frequency, intensity and duration beyond our ability to control them. We're now dependent on rain to put them out. What a terrific time to have a broken hydrological cycle, eh?
Oh yeah, one more thing. Water vapour, of which we now have ever more in the atmosphere, thanks to anthropogenic global warming, is one of the most powerful greenhouse gases. There's more of it up there and it's accelerating the power of the atmosphere to trap solar radiation, blocking its escape back into space.
So, we've got these powerful feedback loops in play but the political narrative ignores them entirely. No, the political narrative focuses on how we cut, no "reduce," greenhouse gas emissions to stay within a target that we have already exceeded in order to avoid tipping points that we've already tipped that could trigger natural feedback loops that are already looping. Hmm, what's with that?
Well then what's the point of this political exercise after all if it's only Kabuki theatre? Ask yourself this. How would the public react if the government said, "Oh, to hell with it. What's the point?"