I am boarding an emission creating aircraft this morning to fly to the East Coast of the United States. I should be back on Friday and will do my best to keep the web log going, as I work on the East Coast.
Flying is universally acclaimed to be a bad thing for the environment because it emits its carbon dioxide and water vapour in the upper atmosphere, where they will do the most damage increasing the green house effect by preventing energy escaping the atmosphere.
These high level particulates released by aircraft also deflect light as it enters the atmosphere, preventing some light from reaching the surface of the earth making the surface receive less light. Studies have shown that in the days when all commercial flights were banned in the United States, after the destruction of the Twin Towers by terrorists, levels of insolation (light reaching the surface) in the United States actually rose measurably and significantly.
The process by which the amount of light reaching the earth’s surface is gradually diminishing is called global dimming. A great deal of work on global dimming has been done by Gerry Stanhill who has been studying sunlight records. He has found that sunlight levels have been falling since the 1950s although the amounts by which they fall varies greatly from one place to another. Falling light levels exist virtually all over the world and occur as the world’s climate is getting hotter. Most scientists were sceptical at first but global dimming is being seen as a real phenomenon and they believe that a chief cause is flying as well as airborne particulates created when we burn fossil fuel and non fossil fuel. The high level vapour trails that aircraft leave behind deflect light as do the emissions that come out of our cars power plants and even those from biomass power plants (such as is proposed at Port Talbot), reducing its intensity and probably in doing so prevent the planet’s climate changing even faster than it is changing now. Paradoxically that which helps cause global warming also disguises its true effects by at the same time causing global dimming.
I do not recommend that increased flying is the solution to rapidly on setting climate change, but merely point out the complexities that are involved.
Filed under: carbon emissions, climate change, pollution, solar energy | Tagged: , aircraft, emissions, global dimming, green house effect, particulates, pollution. global warming
