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Planet Earth Under Threat

This type of Forest could turn against us

  • Julian Hector
  • 20 Dec 06, 02:56 PM

sprucelandscapeblog.jpg

Spruce forest, like this in the rocky mountains, could actually make make global warming worse.

In the last programme of PEuT we run a story by Lara Kueppers of University of California, Merced. She explains in perfect detail the two great physiological processes of plants: Respiration and photosynthesis - And it's the tussle between these two processes, with a forest fire to boot that can make temperate forests contribute to global warming, not combat it.

Gloabl warming is drying the forests in the Rocky Mountains, her research shows. And her work points to the idea that in warming and drying conditions, forests might give up more of their carbon than they absorb. If they do that, they are feeding back positively on global warming..making it worse.

Photosynthesis is the process unique to plants where the (usually) green pigment absorbs sunlight and fuels a process where by the plants make sugars from atmospheric carbon dioxide. Plants also respire just like we do as they go about their bodily functions. Respiration gives off carbon dioxide to the surroundings.

we've all been assuming that if you plant trees the increased forest cover will absorb more carbon. Lara's work shows that with increasing temperatures the fungi and microbes in the forest floor actually speed up their respiration, so the over all effect of the forest is to give up more carbon than they can abosrb.

Drying conditions also make forest fires more serious...burning more than a damp forest - and giving up even more carbon - And fires can be more frequent..releasing the stored carbon.

These are powerful ideas. Forests have been a comfort zone up to now. They also store a lot of carbon - that's a fact. Tropical forests are different to the boreal forests above...they do absorb more than they emit - buit maybe not if they dry out. And they can dry out. The tropical forest fires of Indonesia and Borneo are probably fresh in your minds. We also hear reports of the Amazon dying out. El Nino coupled with global warming can cause havoc with rainfall patterns, so even the tropical forests could cease, in places, to be the damp strore houses of carbon - and if they catch fire, could contribute to the "runaway climate change".

Back to so many of your blogs..the issue is about tackling global warming...And as is discussed in the last programme - let's not rely on trees to bail us out.


Comments  Post your comment

  • 1.
  • At 04:16 PM on 20 Dec 2006,
  • Mark wrote:

The rain forests of Indonesia and the Amazon aren't dying out, they are being deliberately burned down. Those who are concerned about global warming don't seem too interested in putting pressure on governments like Brazil to put a stop to it. They'd rather rant and bash the US for not signing the Kyoto sham.

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  • 2.
  • At 11:09 PM on 27 Dec 2006,
  • Mark Bell wrote:

Actually huge tracts of the US citizenry are also bashing the current US administration's non-Kyoto stance by getting their local city/county authorities to implement the Kyoto protocols anyway. For example please see California's exhaust emission regs.

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  • 3.
  • At 11:43 AM on 17 Feb 2007,
  • Martina Novotna wrote:

This point made here is amazing and underpins the scientific uncertainty about the use of carbon sinks to offset emissions, particularly sought after by the USA and Australia among other countries. However, there is a great danger that this argument can be misused to justify deforestation. The danger is especially enhanced due to the political importance the global warming gained over the last 25 years. Everything seems to be driven by the concern about global warming while other environmental problems cease their importance. Forests are vital habitat and are of great importance to humans. Deforestation is happening at allarming speed and must be stopped. Yes, we cannot rely on trees to bail us out but at the same time this shouldn't be to say that they stay in the way of battling global warming.I know that it wasn't ment in this way but unfortunately there is lot of people out there, unfortunately mostly those in power, who will happilly use this argument to justify the damage caused to the planet by cutting down the trees.

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Concerning global climate change.
New kind of clean energy has been invented!!!
Please open GOOgle and klick metozor and after : index of metozor At is site that explains technical details in easy to understand language. example : http://www.nets.pl/%7Emetozor/for_greenpeace.html or
http://www.nets.pl/%7Emetozor/energy_for_everybody.html
http://www.nets.pl/%7Emetozor/prolog_for_metoz.html
Everyone is able to build just the model of METOZ machine and test it. Please, have a look at http://www.nets.pl/%7Emetozor/supplement.html Perhaps METOZ is some duplicating machine of a clean energy.
Thank you for your time and interest.
E-mail this article to friends.

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  • 5.
  • At 12:03 PM on 20 Feb 2007,
  • Philip V Hackett wrote:

This article explains all about Global Warming

http://www.newsmax.com/archives/articles/2007/2/14/151325.shtml?s=lh

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Phil Brennans editorial linked at comment No. 5 is just another demonstration of the provincial approach of the US media and the manipulation of information by rightwing US politics. While it is true that Canada and the US suffered a particularly cold Winter of 2007 (and this fact is broght forward as proof that no such thing as global warming exists), it's equally true that the same latitudes in Europe had an extremely mild Winter, and that the world's average temperature was the highest ever recorded for the period. It's anyway bad science to use data from one single Winter to prove or confute a theory on climate - a longer view is mandatory and only statistics over decades or even centuries have some meaning in climatic terms.

One fact remains: regardless whether we face a new glaciation or endless draught, we are consuming this planet's resources at an alarming speed. What will we do when we've got no oil or gas left?

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  • 7.
  • At 08:17 PM on 18 Aug 2007,
  • Anonymous wrote:

It not only forests that affect the global warming. Nobody notices the greates and unavoidable threat that perfectly pumps heat into the atmosphere - paved surfaces and roofs. In my estimation, black asphalt emits 10 times more heat than the coresonding surface of a green spot. Red roof is not much behind. On a global i can't say but in my town the temperature is about 4 gegrees higher than in the country side, not to mention forests. In my opinion planting trees and covering roofs with grenery should be stipulated for every new construction. Otherwise humans will have to say ferewell to the planet sooner than expected- but is it bad?

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