Current Science and Climate Change

welsh

Junkmaster
As the politicans debate in Montreal, what is science telling us about Climate Change.

Changing science

Dec 7th 2005
From The Economist print edition

As delegates from around the world meet in Montreal to discuss climate change, what science should inform their deliberations?

THE climate changes. It always has done and it always will. In the past 2m years the temperature has gone up and down like a yo-yo as ice ages have alternated with warmer interglacial periods. Reflecting this on a smaller scale, the 10,000 years or so since the glaciers last went into full-scale retreat have seen periods of relative cooling and warmth lasting from decades to centuries. Against such a noisy background, it is hard to detect the signal from any changes caused by humanity’s increased economic activity, and consequent release of atmosphere-warming greenhouse gases such as carbon dioxide.

The problem is that minor fluctuations that become regular and fuck the ecology up.

Detection is, nevertheless, important, because the climate seems particularly changeable at the moment. Moreover, forming sensible policies towards climate change, as this week’s United Nations Climate Change Conference in Montreal aspires to do, depends on knowing what is going on. Fortunately, the past year has seen the publication of a series of results that help to disentangle signal and noise.

Ok, so what is the evidence that the climate is kind of getting fucked up.

The first, and most basic, is the continuation of the warming trend at the Earth’s surface that has been happening since the early 20th century. The first chart below, assembled by Britain’s Hadley Centre for Climate Prediction and Research and the University of East Anglia, shows that the ten years to 2004 were the warmest decade since reliable measurements began in the early 19th century. Estimates of earlier temperatures made from data such as ice cores and tree rings, though not as reliable as thermometers, suggest the decade may have been the warmest in the past millennium.

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The second result is that the Arctic, a place where any warming trend would be amplified by changes in local absorption of heat as the ice melts, does, indeed, show signs of rapid warming. A report published this year as part of the Arctic Climate Impact Assessment, which synthesised the work of 300 researchers, showed that the amount of sea ice has fallen by 8% in the past 30 years, and also found signs that Greenland’s ice cap is melting more rapidly than in the past.

The third finding is the resolution of an inconsistency that called into question whether the atmosphere was really warming. This was a disagreement between the temperature trend on the ground, which appeared to be rising, and that further up in the atmosphere, which did not. Now, both are known to be rising in parallel.

The fourth is a study by researchers at the Scripps Institution of Oceanography, in California, into changes in the way the world’s oceans have warmed up at different depths over the past 65 years. These match climate models’ predictions of what happens when warming is induced by greenhouse gases better than it matches predictions of the result of changes in the sun’s activity, the main alternative hypothesis for what might be causing the climate to change.
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The fifth is the observation in reality of a predicted link between increased sea-surface temperatures and the frequency of the most intense categories of hurricane, typhoon and tropical storm.

And the sixth, as reported in last week’s Economist, is an observation that ocean currents in the North Atlantic are faltering in ways that computer models of the climate previously suggested would happen in response to increased temperatures.

The signal, in other words, looks strong. That said, there are still a number of uncertainties. For instance, the solar hypothesis is not yet dead. A few researchers who look at the data and agree they show a warming trend nevertheless argue that this may be caused not by man but by nature, in the form of minute increases in the sun’s heat output. That output is known to vary during the course of the 11-year sunspot cycle, as well as over the longer term, and although such changes have not been matched to temperature changes in the way that rises in the level of greenhouse gases have been, they may still be making a contribution.

Another issue is that a second type of pollutant, aerosols such as the minute sulphate particles that form when sulphurous fuel is burned, promote the formation of clouds. These reflect sunlight away from Earth and thus oppose the effect of greenhouse gases. Some have seen this as a possible counterbalance and, indeed, such “dimming” has been noticed in several parts of the world. However, yet another study published this year suggests it is going away as anti-sulphur pollution-control measures kick in.

Perhaps the most important uncertainty, though, is that caused by a lack of enough good-quality, long-term, internally consistent data. Even the industrialised parts of the world, Europe and North America and their adjacent seas, have been well studied for only a century and a half. Too much climate science relies on drawing conclusions from patchy information. It is therefore a nice irony that only under the presidency of George Bush, the bête-noir-in-chief of many environmentalists, has a unified Earth Observation System of satellites, ocean buoys, terrestrial weather stations, balloons and aircraft started to take shape. Though the system involves some 60 countries, the moving spirit is America’s National Oceanic and Atmospheric Administration.

Hoot! America!
(There is hope for us yet!)

Watcha gonna do about it?
That the climate is warming now seems certain. And though the magnitude of any future warming remains unclear, human activity seems the most likely cause. The question is what, if anything, can or should be done.

One option, of course, is to do nothing

Or, the "W" Solution

—or, at least nothing beyond eliminating the sort of economic nonsense, such as subsidising coal mining, that not only encourages global warming (because coal is the most carbon-rich fuel around), but wastes money. Indeed, it is often forgotten that parts of the world would benefit from a hotter climate. In particular, the warming of the Arctic is opening sea lanes that early European navigators avidly sought but were unable to penetrate. The clearing of sea ice will also permit oil-drilling in places hitherto off limits. And a gentle warming should extend the growing season in places such as Canada and Russia.

Always look on the bright side of your life!

Never you mind about those unusually strong tropical storms or the receding coastlines.

Afterall, New Orleans is a den of hedonism, homosexuality and alcoholism (and thus one of the funnest places in the US). Surely this is God's wrath.

Too rapid or too great a warming, though, risks serious, unpleasant and in some cases irreversible changes, such as the melting of large parts of the Greenland and Antarctic ice caps. There is, to put it politely, a lively debate about how far the temperature can rise before things get really nasty and how much carbon dioxide would be needed to drive the process. Unfortunately, existing models of the climate are not accurate enough to resolve this dispute with the precision that policymakers would like.

If greenhouse-gas emissions are to be capped, however, a mixture of political will and technological fixes will be needed. Political will is the subject of the Montreal meeting, which is seeing the opening shots about what, if anything, will replace the Kyoto climate-change protocol after 2012. But a good way to think about the technology is called “stabilisation wedges” and was invented by Rob Socolow of Princeton University.

See chart above.

Political will? Lacking in the US.
Technological fixes- Are they even possible?
Dr Socolow observes that on current trends the amount of carbon dioxide emitted by human activity will double over the next 50 years. He calls the space on the graph below between the trend line and the line representing stability at current levels the stabilisation triangle. That triangle can, in turn, be divided into a number of wedges, each of which represents a way that carbon dioxide emissions might be curbed. This way of looking at things, he observes wryly, decomposes a heroic challenge (eliminating the emissions in the stabilisation triangle) into a limited set of monumental tasks.

Happily most of us old folks will not be around to see you young folks attempt to acheive this heroic task.

What constitutes a wedge is, to a certain extent, a matter of taste. Dr Socolow lists six: greater efficiency, decarbonised electricity, decarbonised fuels, fuel displacement by low-carbon electricity, methane management (methane is a more potent greenhouse gas than carbon dioxide) and natural carbon sinks. Each wedge then breaks down into sub-wedges (for example, decarbonised electricity includes nuclear power, renewable energy, substituting coal with less carbon-intensive natural gas, and capturing and storing carbon dioxide from power stations).

As can be seen from this list, a lot of Dr Socolow’s subwedges rely on the wider deployment and sharpening up of existing technologies, such as ways of generating electricity from renewable energy sources. They also rely on building what might be called “emissions awareness” into a huge range of things that either generate or consume power—a fact that some firms see as a new business opportunity (see article).

The wedge approach also lubricates conceptual shifts. The more hair-shirt sort of environmentalism has emphasised the idea of moving away from fossil-fuel use (though not, heaven forfend, towards nuclear power). Wedge theory, if it may so be described, balances that with thinking about ways to continue burning fossil fuels while keeping the carbon dioxide that generates out of the atmosphere.

One way to do this is to extract it at the power station and inject it into porous rocks deep underground, from which it cannot easily escape. Some oil firms do this already to carbon dioxide that forms part of raw natural gas. Statoil, Norway’s national oil company, has had such a “carbon sequestration” project in the North Sea for almost a decade, and BP now has a similar plant in Algeria.

Power-station extraction could either use the exhaust gases or be pre-emptive, by reacting the fuel with water in a process called steam reformation that yields hydrogen (which is then burned to make the electricity) and carbon dioxide. America’s Department of Energy is sponsoring a series of projects designed to see if either of these techniques can succeed without raising costs too much.

Then comes Dr Socolow’s last wedge. One other carbon-sequestration technology exists, and it is a tried and tested one—photosynthesis. Plants form themselves literally out of thin air, combining carbon dioxide, water and the energy of sunlight to give themselves substance. Photosynthetic carbon sequestration is a game that anyone, rich or poor, can play.

According to David Kaimowitz of the Centre for International Forestry Research, an intergovernmental organisation, 15-20% of greenhouse-gas emissions caused by human activity are the result of the degradation and destruction of forests. Simply replanting the equivalent of what is being lost would thus make a useful subwedge. Indeed, an annex to the Kyoto agreement allows rich countries to pay poor ones to do just that, instead of cutting their own emissions. Not every good idea has to be a new one.

Possible?
Foreseeable?

What do you think?
 
Double post!
More on climate change from popular mechanics-

Looks like that flick The Day After Tomorrow (also known as two days from now and not to be confused with "The Day Before Tomorrow") might have had some point afterall-

http://www.popularmechanics.com/blog/science/2060346.html

Coming Soon to a Region Near You

Looks like The Day After Tomorrow may be arriving as early as this century ... minus the cheesy teenage love story and deep-freeze of the New York Public Library, of course. Computer models now show that—absent of any climate policy—the thermohaline circulation in the North Atlantic Ocean has a 70 percent probability of shutting down in the next 200 years, and a 45 percent chance of doing so in the next 100.

OOps.
Fig2.jpg


This giant oceanic conveyor belt, critical to maintaining the current climate, is driven by cold, dense water that sinks in the Arctic, flows south, and pushes warm surface water from the tropics back up toward the pole. If a combination of melting sea ice and increased precipitation caused by global warming reduces the salinity and density of the sinking water, this conveyor belt could slowly grind to a halt.

Though the same principle inspired rapid, blockbuster-scale climate change on the big screen last summer, New Yorkers are not likely to see a Russian tanker floating up Fifth Avenue any time soon (and thank God, as that would really interfere with my commute). The southern hemisphere would become warmer and the northern hemisphere would become colder, however, heralding a significant shift in climate.

SO buy real estate in the southern hemisphere now!

According to the team of scientists, who are presenting their work today at the United Nations Climate Control Conference in Montreal, a rigorous carbon tax on fossil fuels reduces the potential of a complete collapse to 25 percent. That risk is still unacceptably large, they say, so measures such as carbon sequestration should be given serious consideration.--J. Bogo

And the responses-

Re: Coming Soon to a Region Near You
We will be okay till Jesus returns, so relax. Remember, God is in charge :)

Whatever
What liberal America doesn't want you to know is that the entire atmosphere and carbon dioxide levels can, in fact ,fix itself. So... if we stop now. Maybe it will be okay for our children. But the question is how do you stop. How do you get everyone to stop driving and burning fossil fuels? You can't! Besides everyone who brings up the idea of driving less in the first place never wants to be the one to carry out the plan.

Re: Coming Soon to a Region Near You
It is mind blowing the amount of change we as humans are making to our planet.. which is still increasing expotentially year to year. There OBVIOUSLY has to be a downside to all this change. Significant changes to delicate balance of mother nature should have been obvious when we started. And even if we curb our habits now, the damage to Earth has already been done (and will still continue). I am 20 and this is sad for our future families.
 
We don’t know what the exact effect will be of climate change. There may be benefits as well as drawbacks.

All I know is that Canada has a little more to gain from global warming than most of the world.
 
Funny you mention that. One of my students wrote a paper mentioning that Canada is not that anti-global warming as it means more agricultural output.

But if it also means more extreme weather, I would think the Canadians have more to fear from some wicked Northern storms.
 
I suppose, but in the long run it could mean less cold weather period, as we obtain more of the climate of the American heartland. Although this would mean by area of the country obtaining the climate of the American deserts that are east of the Rockies.
 
one thing to keep in mind is that all this is just theory. they may have evidince backing up their theories, but so did newton before some of his theories were proven wrong.

of course there are also the "laws" put forth by aristotle and plato...

"a lighter object falls at a slower pace than a heavier object"

which is true with air-resistance but that matters more for the shape, but once you put them in a vacum, thats no longer true.

there are always qualifiers for every law or theory, the problem is we may not know what the qualifiers are at this point.
 
Yeah, but doubting or assuming that lighter objects falling slower didn't jeopardize the future development of the planet's ecology at large.

Physics and Mathematics are ALL about theories. There is no knowledge, only assumptions.

The thing with global warming is that the theory fits pretty neatly into the construct of assumptions and theories we already have, more so than any rivaling theory -- and that means it's very likely to be right.

Ignoring the theory would be fatal if it turns out to be accurate -- and with it being accurate being considerably likely, that means by ignoring it you're playing at high stakes and very bad odds.
 
Ah, were totally fucked.

Just learn to accept it and love entropy.

(damn America with its scant regard for the environment)
 
Kan-Kerai said:
It's not just America, chuckles.

That doesn't make it better, does it?

Besides, everyone loves scapegoats -- especially Americans.
 
Incedentally, there are also more pirates now than there were 500 years ago. More shipping, cheap pirate boats, etc. etc. I guess Somalia alone has more than 35000 pirates.
 
Yes, I think that more global warming leads to more pirates. Think about it- more global warming means more open ports, means more potential for pirates.
 
I don't see the connection beteween more open ports and global warming since the water level wil rice and create less ports, however more water means more ocean for the pirates to roam. Soon they will probably steal all of our fish those bastards.
 
Loxley said:
I don't see the connection beteween more open ports and global warming since the water level wil rice and create less ports, however more water means more ocean for the pirates to roam. Soon they will probably steal all of our fish those bastards.
ummmm...as far as I know, if there is more water, due to the ice caps melting through increased global temperatures, there would have to be more ports to facilitate rising water levels and the like, for transport and stuff.

yes all these are, are theories that seem to fit in perfectly with the temperature and climatic change we are experiencing. However, as far as I know from Karl Kruzselnicki, an Australian Scientist/Doctor, we are actually slipping into an ice age that is being negated by the ever increasing global temperatures that MAY be bought upon due to global warming processes. There is strong evidence that suggests that in a few thousand years or so we will be sitting in a deep freeze.

Every hundred thousand (or so) years the world experiences an Ice Age but now we are screwing around with natural systems...o well anything we would do now to try and resolve these problems would have little effect, so we are screwed anyways.

but them damn pirates....

Cheers,
The Duckman
 
That we will eventually have to endure an ice age doesn't neglect global warming.

Global warming doesn't mean the planet gradually heats up until all water is steam and all rock is lava.

Of course the system will eventually stabilize, but the problem is that we might be having an impact on HOW it will stabilize and we might not like the outcome.

Mars pretty stable, but I'm sure most humans are sane enough not to seriously consider living there as-is.


(posted while slightly irritated by the constant soccer bullshit on tv, ignore all contents)
 
Well whenever we experience the full brunt of any supposed global warming, the earth won't be lava and steam crap everywhere, it will just be a swampy, desolate wasteland, probably uninhabitable by no one due to infertile soils and all.

All we are doing now is negating any effect that an ice age may have on our world if it were to hit fairly soon. The earth goes through cycles of ice house and greenhouse satges. Right now we are on the brink of an ice house stage where our world cools. By pumping thousands of tons of Carbon Dioxide into the atmosphere, it creates a greenhouse age (well nearly) and gradually heats our world... Its just one big cycle of cooling and heating... And we are screwing around with it...

Cheers,
The Duckman
 
I think there would be more of every profession, including Pirates, than 500 years ago since there are about 7 times the world population now than 500 years ago.
 
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