Global dimming

My brother-in-law has pointed me to a recent BBC Horizon documentary about something called Global Dimming. Horizon is a science programme that revels in doomsday scenarios (like the island in the Canaries that will soon collapse into the sea creating a mega-tsunami that will devastate the eastern seaboard of the US).

Apparently, the worst effects of Global Warming have been held at bay because of Global Dimming which is caused by the reflection of the sun’s rays by aircraft contrails and high level pollution particles from our industrial output, forest fires and volcanoes.

Proof of Global Dimming became clear as a by-product of 9/11. The global temperature rise over the last century was only 0.6 degrees C. Following 9/11, with all flights in the USA grounded for three days, readings from 5,000 temperature points across 48 states showed an increase of more than 1 degree C for just these three days. In other words, Global Warming is being neutralised by our own high-altitude pollution.

This is a weird one. Environmentalists can take this as proof that Global Warming is actually worse than it seems. On the other hand, polluters can say, "hey, who cares about Co2 output! Just as long as planes keep pumping out their pollution we'll be OK".

All of this leads us to a new headlife league table - the world's top Co2 emitters (tonnes per capita):

1. United States - 5.37
2. Australia - 4.63
3. Saudi Arabia - 3.88
4. Canada - 3.76
5. North Korea - 3.09

(Source: USDOE)

I always knew that the US was the worse offender, but it's interesting to see that they're not that much worse than supposedly "enlightened" countries like Australia and Canada. I believe in Global Warming and something needs to be done: but even as I say that, with three kids I'm not going to get rid of my gas-guzzling minivan. There's the crunch - what are you prepared to give up? Your car? Your big fridge? Are you not going to heat your house?