Prepare for global temperature rise of 4C, warns top scientist

GV:

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Look up Atlantic conveyor and thermohaline circulation.

You might want to rethink:

"Funny enough, any of these events would not have much effect on the average global temperature really...  Just the tropics would hit one extreme while the arctic hit the other extreme.  "

Heh, a bit snide of a comment GV, though why would I expect less? 

Wanna consider the question I was trying to answer and expand on your comment a bit?  Or should I respond in kind with "look up Atmospheric waves, ocean basins, and... umm...  speed of solar wind?"

 

ETA for bubbles....  The second link you've posted goes to a 1997 lecture.  We've learned alot in the past 10 years, which often makes dated material irrelevent today.  Although in this case, it looks like the article is still accurate.  This information is still quite relevant:

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A look at a simple stability diagram shows how it works (Fig. 3). The key feature is that there is a definite threshold for how much freshwater input the conveyor can cope with. Such thresholds are typical for complex, non-linear systems. The diagram is based on Stommel's theory, adapted for the Atlantic conveyor, but experiments with global circulation models also show the same behaviour (Rahmstorf 1996). Different models locate the present climate at different positions on the stability curve - for example, models with a rather strong conveyor are located further left in the graph, and require a larger increase in precipitation to push the conveyor 'over the edge'. The stability diagram is a unifying framework that allows us to understand and compare different computer models and experiments.

The model st?????eudies also revealed another kind of threshold where the conveyor flow can change or break down (Rahmstorf 1995). While the vulnerability in Stommel's theory arises from the large-scale transport of salt by the conveyor, this second type of threshold depends on the vertical mixing in the convection areas (e.g. the Greenland Sea and the Labrador Sea). If the mixing is interrupted, then the conveyor may break down completely in a matter of years, or the locations of the convection sites may shift. This process is known as 'convective instability', and is the 'fast' transition mechanism. We do not yet know where the critical limits of convection are, nor what it would take to set off such an event. Current climate models are not powerful enough to resolve such regional processes accurately. Convective instability could be the mechanism responsible for some of the very fast climatic changes seen in the paleo-climate records. Both mechanisms are summarised in table 1.

"cancel out their net rise in the 20th century" after "several years flatling"?

This is the bean counting world equating statistical results  with events on the ground. Not net effect but "net rise"?

And who has found global termperatures "flatlining"?

Please tell me I'm reading this wrong, that I'm not doing a Rip Van Winkle.

Umm... My answer was in speculation to Bubbles question...  I had included 'I'd be speculative of my answer to this... but here goes  :P" in that post as well.  So there was no quoted material, tis my speculation.

If you want the reasoning...  The circulation stopping wouldn't affect the average temperature of the world, just the distribution of the energy...  Total doesn't change, where it's located does.  Admittadely the forming of new ice around the arctic would add energy to the system, but would be counteracted by the amount of water vapor forming in the tropics.

 

Make sense?  It was a speculative answer to a question posed by Bubbles that none of us seemed to wanted to try to answer.

Noise wrote:

Heh, Dave... That article is painful.

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Last winter, as temperatures plummeted, many parts of the world had snowfalls on a scale not seen for decades.

Global temps haven't plummeted.  We've had a slightly below average north american season (isolated mostly to the west), while the majority of the globe has consistantly been 4-5 degrees warmer than the baseline (1969-1990 I think?).

The snowfall arguement is funny to...  Snowfall comes from freezing rain... The act of water freezing would release energy ;)   If anything, increased snowfall reflects there is additional humidity in the air from warming temperatures.

Normals are set every 10 years, so the current 30 year period for establishing normals is 1971 to 2000. The year isn't over yet. but it appears to be the coldest year globally since 2000, but still warmer than 1999 and any previous year in recorded history prior to  1998 (2005 and 1998 are not statistically different). A short term leveling off of temperatures due to natural variability is not inconsistent with a general warming trend due to the enhanced greenhouse effect from anthropogenic greenhouse gas emissions, and there are forecasts from the Hadley Centre and others that anticipated this leveling off, with significant warming to come in the next decade. The long-term trend is still up, and statements by the denialist fringe that global warming has totally reversed are just so much bullshit.

Heavy snowfalls can occur with both above normal and below normal temperatures. The warmer the airmass is the more moisture it can hold, and thus greater precipitation is associated with warmer termperatures. However below normal temperatures may result in the precipitation falling as snow rather than rain. Snow generally results from the interaction of ice crystals, supercooled water droplets and water vapour within clouds, but can also result from evaporation cooling of raindrops below the cloud.

 

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Normals are set every 10 years, so the current 30 year period for establishing normals is 1971 to 2000. The year isn't over yet. but it appears to be the coldest year globally since 2000

 oh, sorry policywonk... I was referring to the graph in this [url=http://rabble.ca/babble/babble-book-lounge/warmest-october-ever-0] thread[/url] that relates the month of november and october to 1961-1990 means.  Somehow that thread is in the babble book lounge forum though.  hehe.  They'll use 1971-2000 once we hit 2010.

 Though... Where are you getting this year as the coldest since 2000?  I would agree with coldest since 2003 atleast.

 

 

Great post ElizaQ, it was a good read.

 

ElizaQ wrote:

Unfortunately I've heard a couple of people, due to the amount of snow we've gotten this year proclaim that this global warming thing must be a hoax cause look it's cold.  Makes me want to bang my head against the wall.

 
I know how you feel. Aside from pointing out that they are talking about weather, not climate, I tell them that year-to-year and decade-to-decade variation, even extreme hot and cold weather events, have always happened in cool and warm eras alike, even in the Medieval Warm Period and Little Ice Age--even in the last actual Ice Age! Then I ask them what in the world makes them think that those variations would vanish simply because global average temperture is increasing, or that it would negate the effects of Earth's axial tilt, i.e. winter?

Remember, your goal is not to convince or convert the global warming/climate change heckler/denier/obfuscater, which is a total waste of time, but rather to turn it into a teaching moment to reach those watching the discussion who are not knowledgeable enough to know who is telling the truth, you or the heckler/denier/obfuscater. The best way to do that is to make the heckler/denier/obfuscater sound like an ignorant fool without insulting them and calling them an ignorant fool, which would certainly put off others viewing the exchange. Do it with facts, wit and humor, not rancor and insult.

Here's the skinny on the dangers of global warming:

Global temperatures have varied widely over time (up and down).  There have been repeated period of time when nearly all of North America has been covered in hundreds of feet of ice and other periods of time when there has been no ice whatsoever at the poles (and ocean levels were very, very high--at least relative to today).  All of those temperature swings occurred without human intevention.

In outcroppings on my sister's farm in Iowa, her kids routinely find fossilized sharks' teeth.  So, obviously, there was an ocean once covering what today is the midwest USA. 

Did the planet shrivel up and die because of those temperature swings?  No.

If the ocean rises several meters because of a 4 degree increase in temps, will humans now living in coastal regions become inconvenienced? No doubt.

Will the planet die?  No.  No more than the planet was harmed by sea levels being several hundred meters higher than they are today because there was no ice.

It's curious that humans are fixated on what the temperature was in 1998 or 1997 (or 1898, for that matter).  In the long-term scheme of things, a 4 degree temperature swing is meaninglessly insignificant.

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[b]Eleutherophobics of the World...Unite!!![/b]

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In outcroppings on my sister's farm in Iowa, her kids routinely find fossilized sharks' teeth.  So, obviously, there was an ocean once covering what today is the midwest USA. 

That would have been Pangaia days...  There are also glacial boulders littering the midwest landscape.   Earth has been close to a giant snowball and has been warm enough to have a tropical arctic pole.  Yes the Earth can change independant of us...  This does not mean that we cannot influence these changes.

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Will the planet die?  No.  No more than the planet was harmed by sea levels being several hundred meters higher than they are today because there was no ice.

Of course the planet will not die...  But how will we fare?  I forget, how effective was our agriculture back when the sea levels were that many meters higher?

 

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It's curious that humans are fixated on what the temperature was in 1998 or 1997 (or 1898, for that matter).  In the long-term scheme of things, a 4 degree temperature swing is meaninglessly insignificant.

 

Once again, in Earth terms yes.  In our terms?  You've got me curious now Sven, how many lives need to be at risk before you'll consider it meaningfully significant?

How sad for those poor people without airconditioning in Oz.

 

http://www.sciam.com/article.cfm?id=australia-heat-wave-subsi

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By the time global temperatures reach four degrees, much of humanity will be short of water for drinking and irrigation: glaciers in the Andes and Himalayas, which feed river systems on which tens of millions depend, will have melted, and their rivers will be seasonally running dry. Whole weather systems like the Asian monsoon (which supports 2 billion people) may alter irrevocably. Deserts will have spread into Mediterranean Europe, across most of southern Africa and the western half of the United States. Higher northern latitudes will be plagued with regular flooding. Heatwaves of unimaginable ferocity will sear continental landscapes: the UK would face the kind of summer temperatures found in northern Morocco today. The planet would be in the throes of a mass extinction of natural life approaching in magnitude that at the end of the Cretaceous period, 65m years ago, when more than half of global biodiversity was wiped out.

Four degrees of warming would also cross many of the "tipping points" which so concern climate scientists: the Amazon rainforest would likely collapse and burn, as part of a massive further release of carbon from terrestrial ecosystems – the reverse of the current situation, where trees and soils absorb and store a good portion of our annual emissions. Most of the Arctic permafrost will lie in the melt zone, and will be steadily releasing methane, accelerating warming still further. The northern polar ice cap will be a distant memory, and Greenland will be melting so rapidly that sea level rise by the end of the century will be measured in metres rather than centimetres.

[url=http://www.guardian.co.uk/commentisfree/2008/aug/07/carbonemissions.clim...

Now an even newer study from the Tyndall Centre has more bad news:
[url=http://news.scotsman.com/latestnews/Temperature-rises-39will-be-double.4...° temperature rise "almost certain"[/u][/color][/url]

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It is "improbable" global warming will be kept below 4C - double the rise considered safe to avoid climate catastrophe - according to an influential new report.

Internationally, it has long been agreed governments should be aiming to keep a global temperature rise below 2C, to avoid climate change spiralling out of control.

However, a bleak new study by scientists at the Tyndall Centre, a leading organisation for climate change research at the University of Manchester, now suggests we should be adjusting our expectations towards far higher rises.

It warns [b]carbon dioxide in the atmosphere will almost certainly stabilise at levels of at least 650 parts per million (ppm), which is roughly equivalent to a four-degree temperature increase.[/b]

The authors write: "Given the reluctance, at virtually all levels, to openly engage with the unprecedented scale of both current emissions and their associated growth rates, [b]even an optimistic interpretation of the current framing of climate change implies that stabilisation much below 650ppm is improbable."[/b]

 

Transplant wrote:

Sven, you are conveniently ignoring the fact that every single thing that comprises human civilization developed since the end of the last glaciation. That includes cities, agriculture and all technology since stone and bone tools. The human species survived the last glaciation, perhaps even spread across the globe because of it, but human civilization did not because it had not yet developed. And that civilization is designed and built to cope with the climate that we have now, not the altered climate and geography that would be the result of a 4C increase in average temperature.

A 4C or 6C temperature rise would, indeed, be very, very bad.  I do not, however, believe it would result in the extinction of humans, as humans are very adaptable.

That all being said: If global warming is an existential threat (and perhaps it is), then why the hell are we talking about anything else but global warming?  Yet, "climate change" is lost in a veritable blizzard of other "pressing issues".  And doesn't every discussion about a lack of affordable college tuition, insufficient arts funding, middle class wages, GMO foods, etc., etc., etc. only serve to suck vital energy and attention away from the one issue that everything else depends on?  The one issue that, if not addressed, causes everything else to be irrelevant?

If life itself really depended on addressing that one issue, then I would think that people would say, "Let's put aside discussing A, B, C,...Z and focus our attention on addressing the one issue upon which everything else depends.  Once that's solved, we can return to other issues."  And, yes, I understand that some issues are inextricably linked to the issue of global warming...but most are not.

But, because most of those who are concerned about global warming simultaneously engage in discussing, protesting, and hand-wringing about a million other subjects, I am led to conclude that the very advocates of concern about global warming don't really believe that is is as serious as they claim it to be.  Either that or they don't know the first fucking thing about actually getting something done.

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[b]Eleutherophobics of the World...Unite!!![/b]

I quite agree, Sven.  Even many self described "progressives" don't get just how serious climate change is going to be, and especially how long it will last: basically a thousand years or more.

For some insight you might want to listen to Gwynne Dye's three-part Ideas series Climate Wars. You can donload it as three podcasts here:

http://www.cbc.ca/ideas/podcast.html

 

The thread title is "Prepare for global temperature rise of 4C"

Really looking forward to instructions for preparation. Where to start?

Old Jim Lovelock isn't really helpful by this time, eh, FM? But maybe the old fart is not perfect, has overlooked some natural response to rising ocean levels that will save the day? (Besides the culling, I mean). Some physical reaction.

What do these untrained, undisciplined, would-be biologists know, anyway? Right, Sven? (Thanks for the latest Lovelock interview by the way).

George Victor wrote:

The thread title is "Prepare for global temperature rise of 4C"

Really looking forward to instructions for preparation. Where to start?

As posted at #21 above:

 

[url=http://www.guardian.co.uk/commentisfree/2008/aug/11/climatechange][color... a planet 4°C hotter, all we can prepare for is extinction[/u][/color][/url]

Is that cliff more than a metre high? If so, you're safe for now.

M. Spector wrote:

Is that cliff more than a metre high? If so, you're safe for now.

Yes, I think it's about 20 to 25 feet above the water (I never did master Metric) but shoreline erosion is a problem. The back of my garden, close to the edge, has already started to leak over the edge. The Municipality said there's absolutely nothing they can do until the house actually starts to hang over the edge - and the house is probably fifty feet from the edge, as are all the six other homes on this street facing the water. I think I can shore up the edge of the garden with plywood.

Can someone please point me to one or more links showing recent and historical global sea level rise? I think these would be enlightening. A google search found only the Univ of Colorado for me.

 That site shows sea level rising at 3.1mm per year since 1993 and it seems to me holding at that value i.e. not accelerating. This would result in a 30 cm rise over the next 100 years (a bit ove 1 foot). This is far below the projections I think. So: why has it not accelerated? I wonder if other sources give similar results.

Thanks

Thanks Transplant. I will follow up on those leads. If I find any data specific sources I will post them.

nycndp, some area's will see colder temperatures in a warming globe...atleast in the short term...local patterns giving way to stronger global ones.  Altering pressure systems and a changing jet streams will have that effect.  If you look across most of Canada, we've been between 2.5-3 degrees lower for the winter (December to Febuary).  However, if you go into Northern Canada and into the arctic, the temps there have been several degrees above average.  The mainstay of Europe was a little cooler than normal, while the majority of China was over 4 degrees warmer than normal.

Transplant:

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1) We have yet to see the full warming impact from the CO2 that has already been emitted due to the thermal inertial of the ocean, and since that CO2 is not going anywhere soon it will continue to give its gift of warming for many decades to come, if not centuries.

Does this make a technology to 'scrub' the atmosphere of CO2 that much more important?  Not talking simple carbon capture to reduce whats emitted, I mean capturing and isolating CO2 that currently in the atmosphere.

And a side question...  Is water vapour included in the global dimming discussion, or is that only focused on aerosols and particulates?  I ferget.

[url=http://www.guardian.co.uk/environment/2009/mar/12/copenhagen-summary][co... key messages from the scientists at the Copenhagen conference:[/u][/color][/url]

[b]1) Climatic trends[/b]

Recent observations confirm that, given high rates of observed emissions, [color=red]the worst-case IPCC scenario projections (or even worse) are being realised.[/color] For many key parameters, the climate is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived. These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts.

[b]2) Social disruption[/b]

The research community is providing much more information to support discussions on "dangerous climate change". Recent observations show that societies are highly vulnerable to even modest levels of climate change, with poor nations and communities particularly at risk. [color=red]Temperature rises above 2C will be very difficult for countries to cope with,[/color] and will increase the level of climate disruption through the rest of the century.

[b]3) Long-term strategy[/b]

[color=red]Rapid, sustained, and effective mitigation based on coordinated global and regional action is required to avoid "dangerous climate change"[/color] regardless of how it is defined. Weaker targets for 2020 increase the risk of crossing tipping points and make the task of meeting 2050 targets more difficult. Delay in initiating effective mitigation actions increases significantly the long-term social and economic costs of both adaptation and mitigation.

[b]4) Equity dimensions[/b]

Climate change is having, and will have, strongly differential effects on people within and between countries and regions, on this generation and future generations, and on human societies and the natural world. [color=red]An effective, well-funded adaptation safety net is required for those people least capable of coping with climate change impacts,[/color] and a common but differentiated mitigation strategy is needed to protect the poor and most vulnerable.

[b]5) Inaction is inexcusable[/b]

There is no excuse for inaction. We already have many tools and approaches - economic, technological, behavioural, management - to deal effectively with the climate change challenge. But they must be vigorously and widely implemented to achieve the societal transformation required to decarbonise economies. A wide range of benefits will flow from [color=red]a concerted effort to alter our energy economy now,[/color] including sustainable energy job growth, reductions in the health and economic costs of climate change, and the restoration of ecosystems and revitalisation of ecosystem services.

[b]6) Meeting the challenge[/b]

To achieve the societal transformation required to meet the climate change challenge, we must overcome a number of significant constraints and seize critical opportunities. These include reducing inertia in social and economic systems; building on a growing public desire for governments to act on climate change; removing implicit and explicit subsidies; reducing the influence of vested interests that increase emissions and reduce resilience; enabling the shifts from ineffective governance and weak institutions to innovative leadership in government, the private sector and civil society; and engaging society in the transition to norms and practices that foster sustainability.

George Monbiot said:

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If this continues, what does it mean? Six? Eight? Ten degrees? Who knows?

Faced with such figures, I can’t blame anyone for throwing up his hands. But before you succumb to this fatalism, let me talk you through the options.

Yes, it is true that mitigation has so far failed. Sabotaged by Clinton(5), abandoned by Bush, attended half-heartedly by the other rich nations, the global climate talks have so far been a total failure. The targets they have set bear no relationship to the science and are negated anyway by loopholes and false accounting. Nations like the UK which are meeting their obligations under the Kyoto protocol have succeeded only by outsourcing their pollution to other countries(6,7). Nations like Canada, which are flouting their obligations, face no meaningful sanctions.

 So basically it's an overall lack of democracy and accountability in the very nations claiming to be the torch bearers of freedom and democracy.

The most advanced accounting methods are taught in colleges and universities, and include costing of labour, materials, and capital. What else could possibly have value? And governments are finally switching over to more exacting methods used by corporations for years - highly successful corporations, like: General Motors, Ford, World Com, Nortel, Enron, Lehman brothers, Bear Stearns etc 

They can even tell us approximately how many thousand people in Ontario will die of air pollution this year and the next, and scientists can tell them how near we all are to dangerous climate change. And they still drag their feet on things. Why? It's because profit motive and democracy are incompatible.

Noise wrote:

lol, thats a great invisa-post Spector.   People read that one while you can!  I do realize this post brings us one closer to the closing of the thread, but whateva.

What George Monbiot has said here has been echoing around the climate community for quite sometime, though he's the first to bring it to public spotlight like this.  In 2006 (maybe even 2005) on a wunderground discussion blog, the question of 'when will the world take notice' was discussed--posters were betting on the scale of change that must occour, how much of an average temperature change would be needed, and when that would happen. 

Might make an interesting Babble thread...  what type of event would it take before the globe puts the environment as a higher priority than the economy?

I actually don't think that's possible. Environmental changes are too slow for people to notice.

A meteor strike or a major volcanic eruption might do it. Global warming unfortunately does not work on human attention span timescales.

Transplant wrote:

Not water vapour per se, since it is a greenhouse gas, and thus a positive forcing, but definitely water droplets and clouds are. But clouds can be both negative (cooling) and positive (warming), depending on cloud type and altitude.

Water vapour is a positive feedback, not a forcing, due to it's short atmospheric lifetime.

Policywonk wrote:

Water vapour is a positive feedback, not a forcing, due to it's short atmospheric lifetime.

It depends on how you are using the term 'forcing,' PW.

You are quite correct that in the atmosphere water vapour can only act as a feedback to some initial warming, or 'forcing,' and water vapour then adds still more amplifying warming as a greenhouse gas.

But the term 'forcing' is also used to describe any factor that produces a net change in energy balance, be it negative (cooling) or positive (warming). The energy balance does not know or care if that change comes from a 'forcing' or from an amplifying 'feedback,' is merely warms or cools in resonse to it.

The dual use of the term 'forcing' can definitely be confusing.