Question: Is Globel Warming That big an issue?

Kristian Harder answered on 19 Nov 2013:

Predicting climate is very difficult, because it depends on a lot of different factors. Temperature distribution on land, in sea (both surface and deep sea) and of the atmosphere, amount of cloud cover (more clouds means less heat from sun reaches Earth, but also that less heat from Earth radiates back into space – which effect wins?), amount of dust and pollution in the atmosphere, and so on. Even the colour of the surface plays a role. Snow reflects a lot of light. Dark roof tiles and roads much less so – unless covered by snow.
So it’s very difficult to get reliable predictions as to what exactly will happen if temperatures go up by a few degrees on average. But simulation of climate is getting better and better because we understand more and more of those details thanks to a lot of research. And we can test how well we understand the system by feeding our simulations with old weather data and check it really predicts the kind of climate we really ended up having.
Taken all that into account, there is no serious doubt anymore that global warming is happening, and that it’s not a normal fluctuation as they have happened naturally all the time, but that this time it’s something that humans have caused. I say “no serious doubt” because there are many people who question the result of serious and honest climate research, but, quite frankly, those people are absolute lunatics. Or try to protect their own financial or political interest against common sense.
But ok, question number two is: even given that we do seem to warm up the atmosphere by a few degrees, is it really a problem? Three degrees more or less wouldn’t even prompt me to change my jacket, after all. But it really could be a *massive* problem. Three degrees change in *average* temperature can have much more dramatic effects than just having one slightly warmer day. Three degrees more can change the circulation of water in the atmosphere a lot. It can change the amount of ice stored in glaciers and ice caps a lot. The results include a much larger number of massive storms such as the one that just devastated the Philippines. Raising sea levels just a little bit might eradicate island nations such as the Maldives. Low-lying countries like Bangladesh or the Netherlands would see many more serious floods. Rich countries like the Netherlands could probably cope. Poor countries like Bangledesh probably won’t. Changing rain patterns can turn fertile countries into deserts, and of course the other way round. This can cause famine, mass migration, revolution. So, yes, global warming is that big an issue. We may be lucky and things don’t turn out so bad. But is that a risk worth taking? We might not have a second chance of doing it right.
A slight problem in this whole business is that it would take a lot of money and technology from rich countries to address global warming. But the rich countries tend be the ones least affected, because they have money and technology to cope with changing climate. That is a bit of an obstacle in addressing the problem…