Check out this week's Monbiot article. Our favourite loose cannon has hit the target, what does all this cold weather have to do with climate change? Quite a lot. Firstly, this is why we emphasise climate change, not global warming. The global climate is a fascinating system, which we only roughly understand and certainly can have no hope of controlling, especially if we drastically alter it.
Britain, the landmass, is in an especially interesting place. London is roughly parallel to central Canada. Our local climate is temperate, not subarctic, because of systems of heat distribution; most important is the Gulf Stream, which picks up heat in the Gulf of Mexico and forces it through the 90 mile straits between Florida and Cuba, ending up on the European coast.
In the winter we generally sit between warm air from the Azores and cold air from the Arctic. When there is a large pressure difference warm air advances toward the British Isles, when there is little difference in pressure cold air from the north tends to dominate. A key input in this system is artic ice. Ice reflects heat while seawater absorbs and re-radiates it. The arctic ice pack is shrinking. This is reducing the temperature difference between Azores and Artic air, allowing cold air to dominate.
The point about a changing climate is the relative unpredictability of the effect of changing even a single input, such as the amount of sunlight reflected by ice, has. Most human civilisation is based on or near water, either rivers or seas. We are dependent on a reliable climate for reliable food and water. If we mess with our climate we will introduce a number of radical and potentially dangerous variables into the other great system, human society.
As a final note, it is testament to how relatively abstract this subject still is to many people, the fact that climate change deniers are able to obfuscate, confuse and throw up smokescreens. It is still perhaps an issue for propaganda rather than agitation.
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