Climate change

I can almost hear the groans” Oh no not that again”. My reason is that this is an existential threat to all mankind. As Al Gore said – it’s an inconvenient truth. I know it doesn’t sound too bad – the climate a few degrees warmer. It would perhaps be quite nice if England changed to something like the south of France. The reality is much darker. As arctic ice melts huge amounts of fresh water are entering the North Atlantic. This is interfering with the existing circulation in the ocean. It is this flow of warmer surface water, the Gulf stream, which gives England its mild climate. If it stops, and it is already slowing, then Britain becomes more like Norway, wet and cold with a lot of snow.

The basic physics is simple, to a first approximation.  Carbon dioxide is transparent to light from the sun. However it is opaque at the longer infra red ( heat ) wavelengths which are re radiated from the earth after it absorbs sunlight. This radiation is trapped in the earths atmosphere and causes it to warm up. Other gases show similar effects with the most important, methane, far worse than carbon dioxide. Carbon dioxide is produced when fossil fuels like coal,  oil, natural gas or petrol are burnt.

Incidentally diesel engines which are more efficient than petrol ones produce less carbon dioxide. The issue is that they also produce more oxides of nitrogen which can cause respiratory problems at higher levels. There has been much publicity around this issue as some manufacturers tried to cheat by making it appear their engines produced less than reality. The most modern diesel engines have a mechanism for reducing nitrogen oxides. Diesel engines also produce fine particles but particle traps in the exhaust alleviate this.  

Now we can , and will adapt to climate change. Better insulated houses, warmer clothing, agriculture done differently are things which can be changed. The rising ocean level which will flood many coastal cities is a more dramatic change requiring massive adaption. A more aggressive weather with more frequent stronger storms and heatwaves will be more difficult, again stronger structures with better drainage and air conditioning for hot spells is all doable but at a big cost in money and dislocation.

Climate change deniers seem to cluster at the rightward end of the political spectrum. It seems to me they are reacting to those on the left who are trying to piggyback on climate change to urge their political agenda. For example some left leaning critics have tried to say the free enterprise system must be abolished and authoritarian government is necessary. In fact a whole series of leftish views have been tagged on the climate change banner under pretext they are in some way necessary to its resolution. This is almost always absolute rubbish.

Some ideas have a germ of truth. For example meat production is relatively inefficient and ruminants such as cattle produce methane in their digestion. It is therefore legitimate to say one potential way of adapting would be to eat less meat. This is all the more likely as reduced land will be available for agriculture in the future. There are interesting technological developments such as meat free burgers. It may be that there are health benefits from eating less meat.

My sense is that the truth about the reality of climate change is slowly dawning. It seems to me this realisation is being driven by increasingly extreme and destructive climate events. These include droughts leading to fires on a massive scale through to unprecedented rainfall leading to floods. It is depressing that many political leaders not only can’t lead but are active deniers.

It is very encouraging that free enterprise is coming up with some answers. Partly this is some known technology becoming more efficient and lower in cost. For example offshore wind turbines operators are now offering electricity at or below fossil fuel prices. It is depressing that so called climate activists try to criticise big oil companies who are in fact looking hard at alternatives. In all it does appear that industry as a whole is starting to react; for example in the flood of electric vehicles coming on the market. Much now depends on societies reaction. I’m unsure that the hysteria around the “Children’s strike” and Greta Thunberg is helpful.

It seems increasingly clear that the climate crisis will require some form of “negative emissions”; that is actively reducing carbon compounds in the atmosphere. There are also possible ways of reducing solar input. These must be approached with great caution as potential side effects would need careful study. One suggested method is to release a lot of reflective particles high in the atmosphere.

On a lighter note

How many psychologists does it take to change a light bulb?

One, but it really has to want to change.