MOUNTAIN LIFE - Coast Mountains | Winter Spring 2019

50 MLCM WINTER/SPRING 2019 The quantum leaps of climate change go forward and backward. Some span years or decades, others stretch across eons. Take, for instance, the concentration of carbon dioxide in our atmosphere, currently hovering around 408 parts per million. The last time there was that much carbon in the air—about three and a half million years ago—sea levels were 18 metres higher than today. Because of the time lag between cause and effect at geological scales, we’ve ‘only’ warmed the planet by one degree so far (sea levels, which rise far slower than air temperatures, have only come up a few centimetres). Our one- degree world was created two or three decades ago, locked in by the carbon emitted up to that point; even if we’d stopped burning fossil fuels by the turn of the new millennium, southern BC’s snowpack would still be down 20 per cent, California would still be on fire, there would still be a 78 per cent reduction in Artic summer ice… and on and on, across the globe. The difference would have been that things would soon get better. They won’t. Because we haven’t stopped or even slowed our rate of carbon emissions. Instead, 2017 and 2018 set two consecutive records for the amount of carbon spewed into the atmosphere. We’re dumping 37 billion tons per year into the sky. That number, like the gas itself, is impossible to visualize, so think of it this way: the closest the earth has ever come to such a precipitous a rise in atmospheric carbon dioxide was in the lead up to the Eocene, 56 million years ago, when volcanoes warmed the planet by eight degrees. Only we’re pumping CO2 out at 50 times the rate those volcanoes did. This kind of behaviour will turn the kilometre-thick ice sheets over Greenland into a Louisiana swamp. The good news is that scenario is still avoidable. According to the latest report from the International Panel on Climate Change (IPCC), there remains a chance we could limit warming to 1.5 degrees, as world leaders pledged in Paris. To achieve this goal, we’d have to cut today’s global emissions roughly in half by 2030, then reach zero by 2050. This feels like the global equivalent of starting a term paper the night before it’s due. Another major international report released soon after the IPCC’s latest assessment found that we’re currently on track for 3.3 degrees of warming by the end of this century. Nobody really knows what that would look like, let alone what to expect for the following century. Climate change isn’t incremental. Once we go past two degrees, all kinds of unpredictable domino effects and feedback loops start to kick in. This could well be the last decade to avoid irreversible, deep- time catastrophe. The actions we take between now and 2030 will reverberate across millennia. What are our chances? In its penultimate report, the IPCC, time traveller extraordinaire, gamed over a thousand climate scenarios for the coming century. Of these, only eight showed humanity keeping the change to two degrees or less. Climate change is bigger, deadlier, more complex than any challenge our species has faced since we were born in southern Africa more than a million years ago. Back then, fossils suggest, proto-humans were under such constant threat of predation that natural selection kicked into overtime. We had to evolve or go extinct. In response, we developed the very intelligence that carried us around the world, straight into the current fix. Once again, we’re under the kind of pressure that made us who we are. This time it’s not our brain that needs to evolve, it’s our culture. The solutions are drastic but available, spelled out in all the same reports that warn us of the problem. They don’t make for easy reading. But if you like stories about time travel, they might be worth the trouble. 2017 and 2018 set two consecutive records for the amount of carbon spewed into the atmosphere.