Today came a report from the top of the world. The Arctic Ice-Cap is disappearing much faster than was expected. Instead of disappearing (in summer) in fifty years’ time, we are now looking at ten to fifteen years. Boy, are the polar bears in trouble!
This is yet more evidence of a climate-change event we call ‘Global Warming’. There is a large body of evidence to say that this is a man-made event. There are those, in scientific circles who maintain that it’s mostly a natural, cyclical, event. Either way, the planet is getting warmer.
When we look at the long-term history of climate-change events, both cooling and warming, we can tell (from studying ancient ice-cores and geology) that major climate change has never been gradual. It seems that the climate has a habit of ‘tipping’ from one state to another in a few decades. This is because the climate is a very delicate interwoven structure where relatively small changes cause ‘cascades’ of events.
This is where we seem to be now. The loss of thousands of square miles of floating ice won’t have a huge effect on sea levels. It’s when the ice that sits on land melts and adds to the volume of the oceans that levels will be radically affected. However that huge expanse of floating ice (which is also disappearing in the Antarctic) reflects a huge amount of sunlight back into space. The result is a lot more solar energy staying in the atmosphere. The earth warms a little more, the oceans heat up a little more (liquids, by the way, expand when heated) and the sea levels rise a little more.
As the Northern climate heats up, just a little, and as the winters get milder, the Northern Tundra is retreating. On the positive side, releasing vast expanses of relatively unproductive land for agricultural use, on the negative side, causing the permafrost to melt.
The permafrost is a deep layer of surface soil that, just a metre or so from the surface, stays frozen all year round. If you live far enough north, you can freeze your food by digging a hole and putting it in. Free refrigeration! This layer of earth is full of vegetable matter that has never fully broken down, because its frozen state prevents the bacteria in the soil from going to work. As the soil melts, the vegetable matter starts to rot and break down. This process releases methane gas. Methane is a very powerful greenhouse gas. Methane makes carbon dioxide look like pretty tame stuff, when it comes to greenhouse gasses. Kilo for kilo, methane has between twenty and twenty five times the climate effect of CO2. The more methane is released, the faster the permafrost melts, and the methane release accelerates. This is already happening. If you take a look at the globe, the Northern Tundra (and therefore the permafrost) is huge. The amount of methane about to be released is enormous.
And so it goes, one small event triggers a slightly larger one. Then that event triggers others. This is what’s known as a ‘cascade’. Cascades have a habit of starting slow and small then accelerating, at an ever increasing rate, until they become huge. The cascade has begun. The climate is going to tip, and tip very quickly. I’m nearly 60 and I will see it unfold before I pop my clogs. My children’s generation will experience the consequences, and the flora and fauna of the planet are headed for a mass-extinction event.
Of course, the planet will survive. Mass extinctions are nothing new. The long –term result will be the same old planet, populated by a plethora of new species. So why worry?
I worry because when countries drown, huge shifts occur in agricultural production and coastlines change, massive geo-political pressures will doubtless be generated. There will be a whole new balance of ‘Haves’ and ‘Have-Nots’. There will be big winners and big losers. This is the kind of event that starts wars. World wars.
We’ve lived for many decades in a world where global cataclysms haven’t occurred. My parents’ and grandparents’ generations lived through two of them. We seem to think it can’t happen to us. I think it most certainly can, and probably will. My offspring are going to go through some extreme times. They will need to learn to be survivors, fighters and many things they have not been brought up to be, if their off-spring are to survive and floursish.
There are many things we could do to slow-down, and eventually reverse, climate change (man-made or not). All of these things we could have started thirty or forty years ago, but we didn’t. There will now be no way of avoiding the cascade, it has already begun.
The planet will survive. The human race will survive. Many creatures won’t survive. In the meantime, things are going to get very dodgy indeed.
