Global Dimming - Global warming model may be too optisimtic
Global dimming is reducing the amount of direct sunlight falling on the Earth's surface. This is supported by three independent evidences; long term direct sunlight measurement and pan evaporation data; and a short term measurements (during the three days after 9/11 when all air planes were banned in USA) daily temperature differences increased by over 1 degree C.
The cause of global dimming is the particles from the air pollution - which makes the cloud reflects more sunlight back to the space. It seems that global dimming is protecting us from the damaging effect of global warming. However, we all knows that air pollution has significant implication on health and climate change. If we just clean up the air without reducing green house gas at the same time, the current temperature of global warming models would be wrong by several degress - accelerating the effect of global warming and we may reach the point of no return much earlier than models have been predicting.
Here is the transcript of a BBC Horizon program (from 2005) and if you are lucky you may be able to download a copy of the program from the Pirate Bay using search term such as 'global dimming'.
Instead we have to take urgent action to tackle the root cause of both global warming and Global Dimming - the burning of coal, oil and gas. We may have to make very difficult choices, about how we live and how we generate our electricity. We have been talking about such things for 20 years. But so far very little has been done in practical terms. The discovery of Global Dimming makes it clear that we are rapidly running out of time.