What do you make of these recent findings related to global warming and tipping points?

Question

Global warming this century could trigger a runaway thaw of Greenland's ice sheet and other abrupt shifts such as a dieback of the Amazon rainforest, scientists said on Monday.

They urged governments to be more aware of "tipping points" in nature, tiny shifts that can bring big and almost always damaging changes such as a melt of Arctic summer sea ice or a collapse of the Indian monsoon.

"Tipping elements in the tropics, the boreal zone, and west Antarctica are surrounded by large uncertainty"

A projected drying of the Amazon basin, linked both to logging and to global warming, could set off a dieback of the rainforest.

"Many of these tipping points could be closer than we thought," lead author Timothy Lenton, of the University of East Anglia in England, told Reuters of the study.

But it played down some other fears, such as of a runaway melt of Siberian permafrost, releasing stores of methane

http://news.yahoo.com/s/nm/20080204/ts_nm/climate_tipping_dc

Thoughts?

Answer 1

Since the majority of earths scientists agree with the global warming scenario, I find it disheartening that these boards are dominated by these know nothing reactionary types who spout their venom with nothing constructive to say.  They don't believe.  Ok I get it.  So we'll just continue to destroy our planet's ecosystems and its ok because anyone who mentions it is just a pinko trying to foist some hoax on the American people.  Boy and you think environmentalists believe in absurd ideas?

These guys take the cake.

Answer 2

There was a tipping point 2.5 million years ago.  It resulted in the ice age we are currently living in.  Probably increased glaciation from continents nearing the poles resulted in ice which increased the reflection of solar radiation which caused increased glaciation that theoretically resulted in our ice age.  Prior to this, rain forests were more extensive.  More arid forests and savannas were created in Africa and S. America 2.5 million years ago.  It is hard for me to believe that somehow reverting to less glaciation will lead to less rainforest now.  It sounds more likely to be fear mongering.  It seems there can never be a positive result from alarmists.  It would defeat the purpose I suppose.

Answer 3

Pretty sobering.  I wonder why this is coming out years after the 2005 meeting.

Scientists identify 'tipping points' of climate change

http://www.independent.co.uk/environment...

Most and probably all of the nine scenarios are likely to be irreversible on a human timescale once they pass a certain threshold of change, and the widespread effects of the transition to the new state will be felt for generations to come, the scientists said.

"Society may be lulled into a false sense of security by smooth projections of global change. Our synthesis of present knowledge suggests that a variety of tipping elements could reach their critical point within this century under anthropogenic [man-made] climate change," they report in the journal Proceedings of the National Academy of Sciences.

The study came out of a 2005 meeting of 36 leading climate scientists who drew on the expertise of a further 52 specialists. It is believed to be the first time that scientists have attempted to assess the risks of what they have termed "tipping elements" in the Earth's climate system.

The nine elements range from the melting of polar ice sheets to the collapse of the Indian and West African monsoons. The effects of the changes could be equally varied, from a dramatic rise in sea levels that flood coastal regions to widespread crop failures and famine. Some of the tipping points may be close at hand, such as the point at which the disappearance of the summer sea ice in the Arctic becomes inevitable, whereas others, such as the tipping point for the destruction of northern boreal forests, may take several more decades to be reached.

While scenarios such as the collapse of the Indian monsoon could occur within a few years, others, such as the melting of the Greenland ice cap or the West Antarctic ice sheet, may take several centuries to complete. "Our findings suggest that a variety of tipping elements could reach their critical point in this century under human-induced climate change," said Professor Timothy Lenton, of the University of East Anglia, who led the study.

Answer 4

Why don't you look at other less liberal sources before making an assumption.

Answer 5

Just the ramblings of someone reciting the predictions of a theory that does not have data to support itself.

http://wattsupwiththat.wordpress.com/200...

http://wattsupwiththat.wordpress.com/200...

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Answer 6

Can you say alarmist?  I knew you could.  (You have to be a certain age to get that meaning)

Answer 7

Jim:

Don't forget that although warmer air holds more water, the dewpoint is also higher, so there can be a lot of water in the air, yet it doesn't precipitate because the air doesn't cool off.  That is sort of what is going on with the Amazon, a combined effect of dewpoint elevation and shifts in atmospheric circulation.  You have to consider all of the physics, not just the ones you think are in your favor.  

To answer the question:  It's a big old nonlinear system, to think there might not be critical control points is whistling in the dark.  I'm betting the ones they haven't figured out are there are the ones that will be killer.

Answer 8

Ridiculous!

Answer 9

Can you explain in your own words how the amazon is going to die off in ways not including human deforestation?  Also, can you explain how the monsoon's will change in areas like india?  In your own words please.

Because to my understanding, the earth gets wetter as it warms, and drier when its cool.  So are you suggesting that it is just going to stop raining in the amazon?  Are the Andes mountains going to disappear?  How is there going to be less moisture in the air if it gets warmer?

See, you can use your common proponent arguement of, " global warming will cause more rain in some areas, and droughts in others."  Then where is this rain going to be falling if it isnt going to be falling in india, south america, australia, africa, the american south.  It has to rain somewhere, and usually the laws of nature remain constant.  Water will evaporate off of the ocean, and fall on the land somewhere.  Global warming looses credibility every time I read an article like that...

P.S. Jim Z, the "tipping point" 2.5 million years ago was caused by the formation of the land bridge of panama, which changed the ocean currents in ways we arent quite sure of yet.

Answer 10

i don't mind was 65 degrees supper time. think of the people that will eat more because of extra money not spent on winter heating bills. Utilies Companies rich enough.