how will global warming disrupt the natural evolution of ecosystems?

Question

will it simply adjust the rate of species migration and habitat change? do you believe it will also have an impact on the diversity found in ecosystems?
and how will it cause man to adjust his actions to affect the land differently?

what will happen?

Answer 1

Kind of hard to provide an answer as I haven't specifically studied the effects of global warming on evolution although I am aware of the effects on ecosystems in general. Hopefully this answer may give you something to go on...

EFFECT ON ECOSYSTEMS
Global warming affects animals and plants as well as humans.

Parts of Antarctica are now covered in grass and there is a massive migration of animals towards the polar regions, these migrations extend an average of 6.1km further from the equator each decade. Butterflies have extended their territory by some 200km further north in Europe and North America.

In the Arctic the habitat of polar bears and emperor penguins is being threatened. The waters of the Hudson Bay for example, are now ice free for three weeks more each year than they were 30 years ago. Polar bears are starving because they need to venture onto the frozen ice to hunt food. In the worst case scenario in another 10 or 20 years there may no longer be polar bears in this region and within a hundred years they could be extinct.

The ecosystems are interlinked, if one species is affected it will undoubtedly affect others which in turn will affect others. The enforced migration of one animal for example, may result in the starvation of another which in turn could have other knock on effects and so ad infinitum (note 1).

The most extensive report into global warming and climate change predicts that up to 40% of animal species could become extinct due to global warming.


MARINE ENVIRONMENT
The world’s oceans absorb carbon dioxide, a little less than half the amount we have produced – about 150 billion tons in the last 200 years (note 2). Carbon dioxide dissolves in water to form carbonic acid and this is affecting the alkalinity of the oceans. Normally they have a pH of 8.3 (note 3) but this has been reduced to 8.2 and is falling, it’s thought that by the end of the century the pH could drop to 7.7.

Many forms of marine life are highly sensitive to the level of alkalinity. The formation of corals is being affected and plankton, which forms the basis of the marine food chain, is also very sensitive. The increasing levels of carbon dioxide make it harder for many species of fish and shellfish to breathe and reproduce. Changes in the ecology and chemistry of the seas and oceans reduce their ability to absorb CO2, which consequently increases the rate of global warming.


SOURCES AND FURTHER INFO
London Times - http://www.timesonline.co.uk/tol/news/uk/article405824.ece
Animana - http://www.animana.org/tab2/22refugespeciesfeelingtheheat.shtml
Nature - http://sun1.rrzn.uni-hannover.de/nhedinst/NATURE_416_389-395_2002.pdf
BBC - http://news.bbc.co.uk/1/shared/bsp/hi/pdfs/30_10_06_exec_sum.pdf
BBC - http://news.bbc.co.uk/1/hi/sci/tech/4633681.stm
Stanford Uni - http://iis-db.stanford.edu/pubs/20115/naturefingerprints.pdf
AAIS - http://www.sciencemag.org/cgi/content/abstract/305/5682/367


NOTES
1) The effects on ecosystems were studied by Nature and the summary findings published by various organisations. A summary can be downloaded from Stanford University.

2) The amount of CO2 we are emitting is greater than at any other time and the proportion absorbed by the oceans is much smaller.

3) pH stands for per Hydrogen, it is a measure of acidity and alkalinity on a scale of 0 to 14. Seven is neutral, the closer to zero the more acidic and the closer to 14 the more alkaline.

Answer 2

There have been several mass extinction events for which no clear explanations are known. Some work is now going on that has H2S generation in the oceans as a basis.
As water gets warmer, the solubility of oxygen decreases to the point where fish and other oxygen users cannot survive. That level of lowered oxygen solubility will enable the dominance of anaerobic bacteria which generate H2S. Those clouds of H2S kill. The crazy creatures that so massively tilted the ecosystem will be the first species to die off.

Answer 3

Trevor: "In the Arctic the habitat of polar bears and emperor penguins is being threatened. "

Dang!! This global warming is some serious stuff if the "Arctic" habitat of indigenous Antarctic Emperor penguins is affected. That's some environmental sensitivity.

Compared to all the ways in which man has "disrupted" natural evolution, global warming has to be the most natural. The globe is under constant change and ALL life should be thankful for it. Every species in existence today owes that existence to the fact that some other species could not adapt to its habitat/environment.

I think that some of the hair-brained schemes to decrease sunlight reaching the planet, artificial carbon sequestering, and other grandiose climate engineering ideas pose a greater threat to living things. Temperature change will have an impact for sure, pretty much as it has every other time the globe has gone through it. Ultimately it will lead to an increase in biodiversity as living things venture into newly created/vacated niches, trying to capitalize. Over time, some of those species will fail, while others will succeed. It's a pattern that repeats itself constantly over billions of years.

Does that give us an excuse to keep on doing what we have always done? No. We all should re-examine our lives and lifestyles to remove or reduce the excesses which overburden the environment. At the same time, we are going to have to come to terms with the fact that WE ARE NATURAL despite the fact that we have cars and jets, fly into space, or talk over the internet halfway across the globe, all this and many things which we aren't "naturally" hard-wired to do. And everyone of those things have an environmental cost...we just have to have a more economical "budget".

Answer 4

FIRST of all you need to understand GLOBAL WARMING is a NATURAL PHENEMENON which takes place every few thousand years.

The problem today is human impact due to which rate of rise in temperature has gone up considerably and this is not giving species enough time to adjust itself. With slow and natural process species migrate or get accoustmed slowly and once who are not able to adopt to changes get extinct.

Due to fast rise in temperature for which we are the only once responsible, species are dying fast and many will be extinct soon.

Eco system and bio diversity of every region will certainly change, we will loose a vast tract of land to sea and water but will also gain some from under snow, yes, in Arctic region especially. With such wide changes in climatic conditions, environment and the whole system as a whole certainly we will loose many important species.

We need to change our way of living, save forests and try to live more sustainably.

Answer 5

Natural evolution of eco systems.
It will cause the ecosystems to migrate (to keep up with the temperature zones). Slower species have a bigger chance of becoming extinct. There are estimates that the transition between postindustrial climate and when the total effect of climate forcing factors is achieved will cause 33% of all species to become extinct. This will, of course, lead to a great reduction in diversity in the eco systems. As diversity is reduced, the eco system risks total collapse especially if key species are removed. Large diversity in eco systems tend to stabilize them. When abiotic conditions (non-living components in a eco system) stabilize the diversity will once again increase as new species take up niches. Although, the most species diversifull eco systems are the very old ones, such as the rain forest, or the Great barrier reaf. It takes time to develop such large systems.

Human efforts will likely be aimed at containing the effetcs of precipitation in an effort to keep up crop yeilds.

Answer 6

3DM, good catch. Global warming must really be bad if the antarctic penguins are now all up in the arctic region. On the other hand, maybe they don't like the cold, so they moved north. I think Trevor is confused.

Trevor also seems to be confused with this astounding statement - "Parts of Antarctica are now covered with grass..." Parts of Antarctica are closer to the equator than the north slope of the Arctic National Wildlife Refuge, but ANWR thaws every summer. They show us pictures of beautiful grassy plains to convince us that we shouldn't drill for oil there.

So why would it be strange for parts of Antarctica, which are closer to the equator than northern Alaska, to be covered with grass, but perfectly normal for ANWR to be covered with grass? The obvious answer is that it is perfectly normal for parts of Antarctica to be grass covered, but confused global warming alarmists probably wouldn't know that.