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The Great Global Warming/Cooling Thread Part 2

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Sorry Dolos but I'm simply not interested in arguing with you over any of these dodgy opinion pieces any more.

The reason I'm not going to argue with you (and please don't take this too harshly) is because I feel that you, like many other deniers, simply don't want to see the truth, and are clutching at straws. Textbook Denial is core of the problem. That is just my personal opinion, nothing more nothing less and that's why people won't argue with you over everything you post.

Anyway, have a nice day and by the way our carbon emissions are on the rise again. Got any ideas what to do about it? I would genuinely like to hear it.

Edited by Halcyon Daze

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From the evolution of this thread I have read articles from both sides of the argument. Whilst I still remain skeptical about man made global warming I still see no harm in curbing our emissions. If the current western world was to cut all its spending on oil I think that the third world would use this to their advantage to rise into the modern era. Its such a huge argument that can only naturally run its course. There is cause and effect to each possible out come that have major implications to life as we know it. No scientist, engineer, economist or politician could possibly predict the outcome let alone a computer model. We are a long way from resolving this debate......

Peace

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Yes, a long way off. That's why every little step is so important.

People are always looking for some 'silver bullet' to save them but only blood sweat and tears will do it in the end.

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Yes, a long way off. That's why every little step is so important.

People are always looking for some 'silver bullet' to save them but only blood sweat and tears will do it in the end.

But Halcyon...I'm confused! You have repeatedly said the 'debate is over'....but in responding to this by Slybacon

We are a long way from resolving this debate

You reply. "Yes a long way off" Which is it?

And I do agree 100% with what Sly had to contribute. I have no issue in reducing pollutions of any kind even including carbon. I want clean air and a clean planet as well. But thats not at issue. At issue is wether the human contribution to levels of carbon dioxide in the atmosphere are creating catastrophic climate change. I'm not seeing it. So far we have carbon dioxide levels way above what the IPCC warned about and yet the worlds temp has failed to warm up in the last 16 years. But the IPCC said it would. We can measure the accuracy of their predictions and up to now you couldn't argue against the fact that their predictions come to naught...

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I had a random thought. This is just a brain storm and does not represent any plausible evidence to support it. ...

What if the climate was naturally cooling and was heading for an ice age but the human caused global warming has balanced out the effect and now the climate is in some kind of middle ground artificial state?

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Good news

Good snowfall gives new life to glaciers

MANALI: With high-altitude mountains in Himachal Pradesh experiencing up to 100 cm fresh snowfall in November month after 10 years, the abundance of snow on mountains has rejuvenated nearly one thousand glaciers and has ensured uninterrupted supply of water for drinking, irrigation and hydel projects.

Even after years of research on glaciers and climate of Himalayas, scientists have failed to learn the pattern of the weather here. While scanty snowfall and rising temperature in last decade had sparked the possibilities of fast shrinking of glaciers, good spells of snowfall in last three years have changed the trend with glaciers almost growing to their original size. Some scientists say that despite heavy snowfall in winters, the extreme heat in summers is causing the melting of the glaciers with abnormal speed and others say extreme cold in winters is neutralizing the minor effect of risen temperature in summer. Overall, speed of melting of glaciers has reduced over the past few years only due to good snowfall in winter months.

Some say this some say that....

http://articles.time...aciers-snowfall

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I post this as a good news story but for some reason I feel some amoung us get depressed when I do...why is that?

The Himalayas and nearby peaks have lost no ice in past 10 years, study shows

Meltwater from Asia's peaks is much less than previously estimated, but lead scientist says the loss of ice caps and glaciers around the world remains a serious concern.

The world's greatest snow-capped peaks, which run in a chain from the Himalayas to Tian Shan on the border of China and Kyrgyzstan, have lost no ice over the last decade, new research shows.

The discovery has stunned scientists, who had believed that around 50bn tonnes of meltwater were being shed each year and not being replaced by new snowfall.

The study is the first to survey all the world's icecaps and glaciers and was made possible by the use of satellite data. Overall, the contribution of melting ice outside the two largest caps – Greenland and Antarctica – is much less than previously estimated, with the lack of ice loss in the Himalayas and the other high peaks of Asia responsible for most of the discrepancy.

Bristol University glaciologist Prof Jonathan Bamber, who was not part of the research team, said: "The very unexpected result was the negligible mass loss from high mountain Asia, which is not significantly different from zero."

The melting of Himalayan glaciers caused controversy in 2009 when a report from the UN's Intergovernmental Panel on Climate Change mistakenly stated that they would disappear by 2035, instead of 2350. However, the scientist who led the new work is clear that while greater uncertainty has been discovered in Asia's highest mountains, the melting of ice caps and glaciers around the world remains a serious concern.

"Our results and those of everyone else show we are losing a huge amount of water into the oceans every year," said Prof John Wahr of the University of Colorado. "People should be just as worried about the melting of the world's ice as they were before."

His team's study, published in the journal Nature, concludes that between 443-629bn tonnes of meltwater overall are added to the world's oceans each year. This is raising sea level by about 1.5mm a year, the team reports, in addition to the 2mm a year caused by expansion of the warming ocean.

The scientists are careful to point out that lower-altitude glaciers in the Asian mountain ranges – sometimes dubbed the "third pole" – are definitely melting. Satellite images and reports confirm this. But over the study period from 2003-10 enough ice was added to the peaks to compensate.

The impact on predictions for future sea level rise is yet to be fully studied but Bamber said: "The projections for sea level rise by 2100 will not change by much, say 5cm or so, so we are talking about a very small modification." Existing estimates range from 30cm to 1m.

Wahr warned that while crucial to a better understanding of ice melting, the eight years of data is a relatively short time period and that variable monsoons mean year-to-year changes in ice mass of hundreds of billions of tonnes. "It is awfully dangerous to take an eight-year record and predict even the next eight years, let alone the next century," he said.

The reason for the radical reappraisal of ice melting in Asia is the different ways in which the current and previous studies were conducted. Until now, estimates of meltwater loss for all the world's 200,000 glaciers were based on extrapolations of data from a few hundred monitored on the ground. Those glaciers at lower altitudes are much easier for scientists to get to and so were more frequently included, but they were also more prone to melting.

The bias was particularly strong in Asia, said Wahr: "There extrapolation is really tough as only a handful of lower-altitude glaciers are monitored and there are thousands there very high up."

The new study used a pair of satellites, called Grace, which measure tiny changes in the Earth's gravitational pull. When ice is lost, the gravitational pull weakens and is detected by the orbiting spacecraft. "They fly at 500km, so they see everything," said Wahr, including the hard-to-reach, high-altitude glaciers.

"I believe this data is the most reliable estimate of global glacier mass balance that has been produced to date," said Bamber. He noted that 1.4 billion people depend on the rivers that flow from the Himalayas and Tibetan plateau: "That is a compelling reason to try to understand what is happening there better."

He added: "The new data does not mean that concerns about climate change are overblown in any way. It means there is a much larger uncertainty in high mountain Asia than we thought. Taken globally all the observations of the Earth's ice – permafrost, Arctic sea ice, snow cover and glaciers – are going in the same direction."

Grace launched in 2002 and continues to monitor the planet, but it has passed its expected mission span and its batteries are beginning to weaken. A replacement mission has been approved by the US and German space agencies and could launch in 2016.

• This article was amended on 9 February 2012. The original sub-heading read "Melting ice from Asia's peaks is much less then previously estimated" as did the photo caption and text: "Melting ice outside the two largest caps - Greenland and Antarctica - is much less then previously estimated". These have all been corrected.

http://www.guardian....ains?intcmp=122

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There's a very simple explanation for this so I won't bother.

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Why not post your explaination. Other people are reading as well ;)

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Researchers have found parts of our coral reefs are more resistant to ocean acidification than first thought, casting a ray of hope on the future of our reefs.

The study, published in Nature Climate Change today, details their analyses of the mineral structure of coralline algae, which form a hard ridge around the reef, protecting delicate corals from harsh waves and holding the structure together.

They discovered an extra mineral, dolomite, in coralline algae, which made the organism less susceptible to being dissolved in increasingly acidic oceans.

“A coral reef is like a house – the coral are the bricks, but the coralline algae are the cement that holds it all together,” explains lead author and PhD candidate with the ANU Research School of Physics & Engineering, Merinda Nash.

“Researchers are concerned that when atmospheric carbon levels rise and ocean acidity increases, the magnesium calcite which makes up the coralline algae will dissolve first, threatening the very foundations of the reef.

“However, in a rare piece of good news, we found when we analysed algal samples from Heron Island on the Great Barrier Reef that the cell spaces in the algae were filled with dolomite, the same strong mineral that makes up the Dolomite Alps in Italy.

“Dolomite is about half magnesium and half calcium and is less susceptible to acidity than the magnesium calcite, meaning the structure of the coral reefs is stronger than previously thought.”

Dr Brad Opdyke from the ANU Research School of Earth Sciences, who collaborated with Nash on the paper, together with other researchers from Australia, Japan and America, said:

“Coralline algae play a really important role in the architecture of the reef. Without it, the reef would just be a big pile of rubble.

“The clouds of climate change are very dark, but now there is this thin silver lining. The dolomite may just make some of the coralline stable enough to keep holding things together.”

Past research has shown that the structure of a coral reef consists mainly of forms of calcium carbonate, a mineral formed in the skeletons of coral and algae and laid down in sedimentary layers over thousands of years.

The algal skeletons are made of a type of calcium carbonate called magnesium calcite which contains about 10 to 20 per cent magnesium instead of calcium.

“It’s a much weaker structure than the version used by other organisms and is quite vulnerable to rising acidity levels.

“But the dolomite-rich coralline algae are better able to resist rising acidity levels. There is less space for sea water to circulate and less surface area for the acidic water to act,” said Nash.

http://news.anu.edu....-climate-cloud/

A WIDESPREAD belief that the world's coral reefs face a calamitous future due to climate change is proving less resilient than the natural wonders themselves.

Rising sea temperatures, storm damage and ocean acidification have grabbed the headlines as looming threats to reef survival.

But as each concern is more thoroughly investigated, scientists are finding nature better equipped to cope than they had imagined.

The latest research, published in Nature: Climate Change today, blows away the theory that reefs were doomed due to rising ocean acidification caused by the higher take-up of carbon dioxide in the seas.

Researchers have found a common coralline algae that grows at the leading edge of coral reefs is not nearly as susceptible to changing ph levels as coral because it contains high levels of dolomite.

In fact, the dolomite-laden algae has a rate of dissolution six to 10 times lower than coral's.

The good news is that dolomite-rich coralline algae is common in shallow coral reefs across the world.

"Our research suggests it is likely they will continue to provide protection for coral reef frameworks as carbon dioxide rises," the paper says.

Lead author Merinda Nash, a PhD candidate with the Australian research school of physics and engineering, says the phenomenon has been overlooked because research to date has been on coral, not coralline algae.

"It is not very sexy so it has not got a lot of attention," she said.

"What the research demonstrates is there is a lot we have yet to understand about coral reefs."

This is a sentiment echoed by James Brown of the Kimberley Coral Research Station, who believes the hot water corals of the Kimberley coast hold a treasure trove of answers for marine biologists.

Mr Brown has questioned why the Kimberley coral reefs were thriving in water temperatures and at acidification levels well outside of the limits that conventional science said should be inhospitable for their survival.

"Measurements of dissolved carbon dioxide have shown levels of up to 50 parts per million compared with the average of 28 parts per million," Mr Brown said.

"This is the outer limit of what scientists had believed would be habitable for corals.Water temperatures are also at the top end of what coral biologists say it is possible for corals to survive in.

"The more we find out about the Kimberley, the more it rewrites the book on coral biology."

Further counter-intuitive results on coral survival have come from an extended project on the Great Barrier Reef to measure the health of deep corals.

The Catlin Seaview Survey has found the damage to coral reefs is literally skin deep, with corals located in deeper water below even the worst impacted sites thriving and in pristine condition. The findings raise the possibility that damaged corals may have an increased opportunity for recovery by recruiting new corals both from adjoining reefs and those located immediately below.

The early findings from the survey have astounded the scientists involved, including Ove Hoegh-Guldberg, a leading global figure in raising concerns about crown of thorns starfish, coral bleaching and ocean acidification.

"The survey has shown that deeper reefs may be protected to an extent from some of the perils of climate-driven events such as mass coral bleaching and storms," he said. "These deeper corals may be important refuges if we get big changes in the shallows."

http://www.theaustra...6-1226533259306

fascinating

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Such a heated debate here! I like!

Of all the back and forth arguments I'm seeing here, only a small percentage of them deal with or make comparison in any sort of definitive time period. Global warming/cooling is something that is generally measured in hundreds even thousands of years? Talk of "ice ages" for example. An "age" would be a significant period of time.

Then there is people arguing apparent temperature rises and emissions increases over the period of the "industrial revolution". Now in retrospect to the aforementioned "ages"; being massive changes in our global state, the industrial revolution has lasted for a blink of an eye.

Now, considering that we have to make logical inferences on previous changes in the earths climate through scientific inquiry and mathematical guess work (that could prove fallacious in years to come) and had no accurate measuring tools for measuring mean ocean temperatures, atmospheric concentrations of varying substances, etc, etc until very recently... How can we make such broad assumptions, for example the worlds temperatures are rising/cooling because of X reason?

Is it possible that this variation is simply an anomaly in measurement, or in the earths natural cycle? Or does it lack relevance because it is only measuring changes of such a small period of time?

I digress.

I think the insatiable need for profit from exploiting such an abundant energy source as fossil fuels is incredibly wasteful and short sighted. It has stymied/suppressed research into utilising some of the most obvious of energy sources that power our planet, for example Solar/thermal and tidal forces. That of course is another topic entirely and I'm yet to have an opinion on whether or not use of non renewables such as fossil fuels post industrial revolution is having an impact on the planet. Has had an impact on society, sure. Made an impact on the overall state of the planet? Undetermined. Also why would any civilisation build an existence that is reliant on a non renewable resource anyway?

Edited by Safez
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Also why would any civilisation build an existence that is reliant on a non renewable resource anyway?

The same reason they still continue to hold renewables back. They make billions of dollars out of it.

They can control fossil fuels but renewables are 'power to the people'.

Has had an impact on society, sure. Made an impact on the overall state of the planet? Undetermined.

It's easy to measure how much carbon dioxide we are adding to the atmosphere.

Just add up all the coal, oil and gas we are burning, then add to it all the carbon added through deforestation and farming. Add in the methane from the livestock industry while we're at it, and now add all the feedback cycles that are starting to become measurable (like increasing rates of bushfires and melting permafrost).

we've nearly doubled the amount of carbon dioxide that should be in the atmosphere

post-8867-0-14251100-1355287003_thumb.pn

More carbon means higher temperatures. It really is that simple.

Edited by Halcyon Daze

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I think the insatiable need for profit from exploiting such an abundant energy source as fossil fuels is incredibly wasteful and short sighted. It has stymied/suppressed research into utilising some of the most obvious of energy sources that power our planet, for example Solar/thermal and tidal forces. That of course is another topic entirely and I'm yet to have an opinion on whether or not use of non renewables such as fossil fuels post industrial revolution is having an impact on the planet. Has had an impact on society, sure. Made an impact on the overall state of the planet? Undetermined. Also why would any civilisation build an existence that is reliant on a non renewable resource anyway?

Money, together with very little in the way of forward planning from governments. This is a great post and to me it gets to the crux of the matter, even if it wasn't for climate change, this is a really stupid way to run our civilisation. Then chuck climate change on top, and you realise that it's more than just stupid, it's criminal and has the potential to destroy the one thing we need to survive; out environment.

Of all the back and forth arguments I'm seeing here, only a small percentage of them deal with or make comparison in any sort of definitive time period. Global warming/cooling is something that is generally measured in hundreds even thousands of years? Talk of "ice ages" for example. An "age" would be a significant period of time.

Then there is people arguing apparent temperature rises and emissions increases over the period of the "industrial revolution". Now in retrospect to the aforementioned "ages"; being massive changes in our global state, the industrial revolution has lasted for a blink of an eye.

Now, considering that we have to make logical inferences on previous changes in the earths climate through scientific inquiry and mathematical guess work (that could prove fallacious in years to come) and had no accurate measuring tools for measuring mean ocean temperatures, atmospheric concentrations of varying substances, etc, etc until very recently... How can we make such broad assumptions, for example the worlds temperatures are rising/cooling because of X reason?

Is it possible that this variation is simply an anomaly in measurement, or in the earths natural cycle? Or does it lack relevance because it is only measuring changes of such a small period of time?

Actually, the science is pretty cut and dried. CO2 is a greenhouse gas, it causes heat to be trapped in an atmosphere. There is much debate on how much damage the extra heat will cause, but damage is certain. Only climate change deniers don't accept that CO2 is a greenhouse gas and will cause damage - why, is anybody's guess, and why they want to continue to increase production of a pollutant that is destined to run out with severe consequences, is way beyond my understanding.

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Both valid points, I must ask though, as the atmosphere of the earth is not really a constant, even body and is constantly in flux; Is there a possibility that these kind of reasonably high emissions haven't existed in the vast history of the Earth and we are reading the warning signs incorrectly.

For example. A lot of the world used to be covered in megaflora and fauna. Can you imagine a wildfire that wipes out an area of vegetation the size of say California, combined with the usually reported high volcanic and tectonic plate action sending mass amounts of emissions into the atmosphere? Yet Earth has still managed to maintain life to this point.

I think what we should be more concerned about is environmental pollution caused by irresponsible companies peddling non renewables to the masses. The Deepwater Horizon oil spill in the Gulf of Mexico being one example.

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Good points Safez, these are the same questions I've often pondered myself.

The way I see it the earth's carbon dioxide levels are in flux but it is over a time scale of millions of years.

The mega fauna and flora came out of the carboniferous period where the atmosphere had high carbon levels and the planet was much warmer resulting in large life forms.

In the long term, things will probably repair and evolution will keep rolling along but it will take millions of years to happen. Such mass extinction events have also happened naturally but this one is man made and that's not something we should be particularly proud of.

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Is it worth the risk? Are fossil fuels really that good that it's worth risking destroying the environment? Especially since they are going to run out at some point anyway? A a society, we run risk assessments all the time, the risk of cancer is so high that we run massive advertising campaigns to try and stop it, even when it is not particularly preventable!

Your doctor says you have increased levels of cholesterol in your blood, you don't want to stop eating the foods (they taste sooo good!) and so your excuses for not cutting back are "the doctor can't tell me when I will die of a heart attack, let alone if I will, he just says there is an increased chance of it, so I'm going to chance it because I like eating the food, even though there are alternatives which will do the job, I just don't like them very much".

But this is potential death on a planetary scale, for many, many species, and, unlike the human lifespan, nature is likely to live indefinitely so ultimately the risk is much, much greater.

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Both valid points, I must ask though, as the atmosphere of the earth is not really a constant, even body and is constantly in flux; Is there a possibility that these kind of reasonably high emissions haven't existed in the vast history of the Earth and we are reading the warning signs incorrectly.

For example. A lot of the world used to be covered in megaflora and fauna. Can you imagine a wildfire that wipes out an area of vegetation the size of say California, combined with the usually reported high volcanic and tectonic plate action sending mass amounts of emissions into the atmosphere? Yet Earth has still managed to maintain life to this point.

I think what we should be more concerned about is environmental pollution caused by irresponsible companies peddling non renewables to the masses. The Deepwater Horizon oil spill in the Gulf of Mexico being one example.

Awesome post and contribution Safez. Thankyou. I look forward to more from you.

Quick question, many more will likely follow but what is your opinion on the term denier as frequently used here? The question may seem odd but there is a point I will get to....

And please whitewind...no more anologies... :lol:

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I think the term 'denier' runs in the same parallel as 'alarmist'. It's a broad categorization that seems to try and lump people into two categories, forcing them to a black and white opinion on the subject. This is something I don't like to see as it's pretentious and really, shows the narrow mindedness of some people.

The mega fauna and flora came out of the carboniferous period
. Sure, this may be the case but what about the permian, triassic and jurassic periods that followed? The age of the dinosaurs. Some of the largest creatures to inhabit the earth. Scientific inquiry has us believe that atmospheric concentrations of Co2 and global temperature in general was higher than it is today.

Was the Earth indeed warmer during this period? Ok. So could it not become warmer again as part of it's regular cycles or is the temperature trends we are observing in our very recent history the cause of the Earth playing "catch up" looking to return to these levels? Possibly due to an collision with an interstellar body that caused climate change on a scale that is orders of magnitude greater than the emissions of all mankind in the short period of our industrial revolution?

Let's remember the debate here is whether the planet is warming/cooling as a result of man made emissions. It's not a debate on mankinds pollution of the environment. That has been more than demonstrated (acid mine drainage, offshore oil spills, deforestation, etc).

Man made extinction event? Perhaps. Could also be that it's not possible to make such a broad statement such as this because of the period of time being measured. I'm still interested to know how our climate change scientist arrived at the decision that the earth has gained X degree of global temperature rise/fall over pre industrial levels... How long have they been monitoring atmospheric concentrations of particles in our atmosphere and the global temperature of the earth? They'd be forced to make a judgement call based on scientific enquiry and mathematical guesswork.

Now one could argue that the science is solid, however someone else could argue that scientific opinion is based on general consensus and hasn't always proven to be the correct answer to some pretty fundamental opinions on our existence (eg: The world being flat. The sun revolving around the earth, General Relativity, The standard model of particle physics, etc)

I think there is no question or debate that mankind needs to curb it's use of non renewables and reduce emissions from an environmental point of view. Whether those emissions will have any kind of bearing, to the point of causing temperature changes that will have a calamitous effect on life as we know it, is yet to be determined. I'm of the opinion we will fuck our landmasses and oceans to the point of non-sustainability through other means before atmospheric disparity and temperature increase/decrease can affect us. Those "other means" as I've so broadly termed it may indeed be a causative agent in that atmospheric disparity and temp increase/decrease but I think it's too early to say that climate change will be the number one cause of our demise or "mass extinction event"

Out of curiousity, what is the main concern of those who believe in global warming/cooling? Is it fear that if the temperature increases/decreases we will be unable to sustain food crops and we will have to deal with rising sea levels?

Edited by Safez
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EDIT - Deleted double posts -_-

Edited by Safez

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Warming climate unlikely to cause extinction of ancient Amazon trees, study finds

warmingclima.jpg

A giant kapok tree on the banks of the Amazon River.The species, Ceiba pentandra, was the youngest (less than 1 million years) Amazon tree species in a genetic study by University of Michigan evolutionary biologist Christopher Dick and his colleagues. Photo by Rogerio Gribel, Instituto Nacional de Pesquisas da Amazonia and Instituto de Pesquisas Jardim Botanico do Rio de Janeiro.

New genetic analysis has revealed that many Amazon tree species are likely to survive man-made climate warming in the coming century, contrary to previous findings that temperature increases would cause them to die out.

A study, published in the latest edition of Ecology and Evolution, reveals the surprising age of some Amazonian tree species – more than 8 million years – and therefore shows that they have survived previous periods as warm as many of the global warming scenarios forecast for the year 2100.

The authors write that, having survived warm periods in the past, the trees will likely survive future warming, provided there are no other major environmental changes. Although extreme droughts and forest fires will impact Amazonia as temperatures rise, the trees will likely endure the direct impact of higher temperatures. The authors recommend that as well as reducing greenhouse gas emissions to minimise the risk of drought and fire, conservation policy should remain focused on preventing deforestation for agriculture and mining.

The study is at odds with other recent research, based on ecological niche-modeling scenarios, which predicted tree species' extinctions in response to relatively small increases in global average air temperatures.

Study co-author Dr Simon Lewis (UCL Geography) said the findings were good news for Amazon tree species, but warned that drought and over-exploitation of the forest remained major threats to the Amazon's future.

Dr Lewis said: "The past cannot be compared directly with the future. While tree species seem likely to tolerate higher air temperatures than today, the Amazon forest is being converted for agriculture and mining, and what remains is being degraded by logging, and increasingly fragmented by fields and roads.

"Species will not move as freely in today's Amazon as they did in previous warm periods, when there was no human influence. Similarly, today's climate change is extremely fast, making comparisons with slower changes in the past difficult.

"With a clearer understanding of the relative risks to the Amazon forest, we conclude that direct human impacts – such as forest clearances for agriculture or mining – should remain a focus of conservation policy. We also need more aggressive action to reduce greenhouse gas emissions in order to minimise the risk of drought and fire impacts to secure the future of most Amazon tree species."

The 12 tree species used in the study are broadly representative of the Amazon tree flora. Samples were collected in Panama, Ecuador, Brazil, Peru, French Guiana and Bolivia.

To determine the age of each tree species researchers extracted and sequenced DNA, analysing the number of genetic mutations. Using a molecular clock approach and population genetic models they estimated how long it would take for each of the species to accumulate the observed number of mutations, providing a minimum age for each species. They determined that nine of the tree species had existed for at least 2.6 million years, seven for at least 5.6 million years, and three for more than 8 million years.

With reference to climatic events that have occurred since those tree species emerged, the authors inferred that the tree species had previously survived warmer climates. Air temperatures across Amazonia in the early Pliocene Epoch (3.6 million to 5 million years ago) were similar to Intergovernmental Panel on Climate Change (IPCC) mid-range projections for the region in 2100. Air temperatures in the late Miocene Epoch (5.3 to 11.5 million years ago) were about the same as IPCC projections for the region in 2100 using some of the highest carbon-emission scenarios.

More information: The paper "Neogene origins and implied warmth tolerance of Amazon tree species" is published in the December 2012 edition of Ecology and Evolution.

http://phys.org/news/2012-12-climate-extinction-ancient-amazon-trees.html

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I was discussing this today with a friend. Many species can survive quite well out of their natural range, but frequently what is most impacted by a change in environment is the frequency of flowering and the incidence of seed set. So while trees may continue to live for a long time, it might be that they do not produce offspring as easily. Combined with massive habitat loss and the introduction of weed species, the impact on natural environments will still be significant.

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yeah, i don't think the authors were saying the trees are in the clear, just that all other things being equal, atmospheric warming won't be as harmful as previously thought. but all other things aren't equal. besides, there's lot and lots of other tree species being systematically wiped out due to climate change.

although i did think of a fun game, "what would the australian headline be?"

something like "new study shows global warming effect on amazon harmless"

or from the daily telegraph:

"new study blows climate change effects out of the water"

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Combined with massive habitat loss and the introduction of weed species, the impact on natural environments will still be significant.

This isn't climate change, it's environmental pollution by manmade actions, let's not confuse or compare this. Environmental pollution would seem to be much more significant than "a degree or two of warming"

there's lot and lots of other tree species being systematically wiped out due to climate change.

Could you be more specific? and by who's authority or 'scientific finding' are these trees being eradicated due to climate change?

Also, lets put things into perspective here for a moment before people start screaming think of trees! or We need our trees for carbon capture to reverse this climate change!

The biggest carbon sink on the planet is the worlds oceans. That is because the oceans of the world cover around 97% of it. Terrestrial plants provide atmospheric oxygen through their respiration and yes, do provide some carbon capture. However it's a fraction of the amount.

Again, I'm not "having a dig" at anyone's opinion on this subject so don't be offended if my writing style comes across that way. Although I really shouldn't have to say that, because if people do take it personal, they're likely not worth talking to about the issue anyway.

Edited by Safez

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Ryan S Anderson et al., Modeling the Effects of Climate Change on Whitebark Pine Along the Pacific Crest Trail

The Pacific Crest Trail (PCT), one of eight National Scenic Trails, stretches 2,650 miles from Mexico to the Canadian border. At high elevations along this trail, within Inyo and Sierra National Forests, populations of whitebark pine (Pinus albicaulis) have been diminishing due to infestation of the mountain pine beetle (Dendroctonus ponderosae) and are threatened due to a changing climate. Understanding the current and future condition of whitebark pine is a primary goal of forest managers due to its high ecological and economic importance, and it is currently a candidate for protection under the Endangered Species Act (ESA). Using satellite imagery, we analyzed the rate and spatial extent of whitebark pine tree mortality from 1984 to 2011 using the Landsat-based Detection of Trends in Disturbance and Recovery (LandTrendr) program. Climate data, soil properties, and biological features of the whitebark pine were incorporated in the Physiological Principles to Predict Growth (3-PG) model to predict future rates of growth and assess its applicability in modeling natural whitebark pine processes. Finally, the Random Forest algorithm was used with topographic data alongside recent and future climate data from the IPCC A2 and B1 climate scenarios for the years 2030, 2060, and 2090 to model the future distribution of whitebark pine. LandTrendr results indicate beetle related mortality covering 14,940 km2 of forest, 2,880 km2 of which are within whitebark pine forest. By 2090, our results show that under the A2 climate scenario, whitebark pine suitable habitat may be reduced by as much as 99.97% by the year 2090 within our study area. Under the B1 climate scenario, which has decreased CO2 emissions, 13.54% more habitat would be preserved in 2090.

Wendy Foden et al., A changing climate is eroding the geographical range of the Namib Desert tree Aloe through population declines and dispersal lags

While poleward species migration in response to recent climatic warming is widely documented, few studies have examined entire range responses of broadly distributed sessile organisms, including changes on both the trailing (equatorward) and the leading (poleward) range edges. From a detailed population census throughout the entire geographical range of Aloe dichotoma Masson, a long-lived Namib Desert tree, together with data from repeat photographs, we present strong evidence that a developing range shift in this species is a ‘fingerprint’ of anthropogenic climate change. This is explained at a high level of statistical significance by population level impacts of observed regional warming and resulting water balance constraints. Generalized linear models suggest that greater mortalities and population declines in equatorward populations are virtually certainly the result, due to anthropo- genic climate change, of the progressive exceedance of critical climate thresholds that are relatively closer to the species’ tolerance limits in equatorward sites. Equatorward population declines are also broadly consistent with bioclimatically modelled projections under anticipated anthropogenic climate change but, as yet, there is no evidence of poleward range expansion into the area predicted to become suitable in future, despite good evidence for positive population growth trends in poleward populations. This study is among the first to show a marked lag between trailing edge population extinction and leading edge range expansion in a species experiencing anthropogenic climate change impacts, a pattern likely to apply to most sessile and poorly dispersed organisms. This provides support for conservative assumptions of species’ migration rates when modelling climate change impacts for such species. Aloe dichotoma’s response to climate change suggests that desert ecosystems may be more sensitive to climate change than previously suspected.

David B. Lindenmayer1, William F. Laurance2, Jerry F. Franklin3, Global Decline in Large Old Trees

Large old trees are among the biggest organisms on Earth. They are keystone structures in forests, woodlands, savannas, agricultural landscapes, and urban areas, playing unique ecological roles not provided by younger, smaller trees. However, populations of large old trees are rapidly declining in many parts of the world, with serious implications for ecosystem integrity and biodiversity.

edit: this is from a brief 5 minute search. i'm sure if i was willing to spend any more time on it i'd come up with a lot more.

Edited by qualia

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