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Nov 20, 2012

Why 4 degrees will end the world as we know it: World Bank

The World Bank has produced an alarming report that puts in context the risks of inaction on emissions reduction and climate change. It doesn't make for pleasant reading.


The World Bank yesterday released a report prepared by the Potsdam Institute spelling out what the world is likely to experience if it warmed by 4 degrees — that’s looking increasingly likely by the end of the century without some serious policy changes by governments globally.

The report essentially attempts to summarise much of the research literature that has built up since the 2007 fourth IPCC Assessment Report and puts it in the context of the path we’re on unless we start taking this problem seriously. It doesn’t make for pleasant reading. World Bank President Dr Jim Yong Kim says “it is my hope that this report shocks us into action”, as he believes “a 4 degree world can, and must, be avoided”.

For the World Bank, with a primary purpose to help impoverished nations out of poverty, “the lack of action on climate change not only risks putting prosperity out of reach of millions of people in the developing world, it threatens to roll back decades of sustainable development”.

The chart below provides an impression of the alternative emission paths and their likely implications for temperature rise. According to the report, we are on a path illustrated by the red line. However, if governments follow through on the pledges they’ve made at the UN’s Copenhagen and Cancun summits then it would put us on the purple line, giving a mean temperature rise estimate of 3 degrees.

But even this path still carries a 20% chance of temperature exceeding 4 degrees. If governments don’t make good on their pledges then the red line would imply a 40% chance of warming above 4 degrees.

Median estimates of temperature rise from probabilistic projections for several scenarios

The latest research, unlike older assessments, is more confident that land-based ice, and not just thermal expansion of existing sea water, will play a significant role in sea level rise. Older assessments were hopeful that increased snow falls might occur over Greenland and the Antarctic that could offset any melting from higher temperature. Unfortunately, the rate of land ice contribution to sea level rise has increased by about a factor of three since the 1972–1992 period. And both the Greenland and Antarctic ice sheets have been losing mass since at least since the early ’90s.

The chart below illustrates that our current emissions path (the red line) gives a mean estimate of a one metre rise in sea level by the end of this century. However, sea level would continue to rise substantially after this point. For example, even if global warming was limited to 2 degrees, global mean sea level could still rise by between 1.5 and 4 metres above present-day levels by the year 2300.

Probablistic projections of sea level rise for different emission scenarios

Rising temperatures will lead to increased likelihood of extreme weather events and heat waves. The report notes that the past decade has seen an exceptional number of extreme heat waves around the world. These events — Victoria’s 2009 heat wave and associated severe bushfire; Russia in 2010 (which claimed 55,000 lives); Europe in 2003 (70,000 premature deaths); the US in 2012 — were highly unusual with monthly and seasonal temperatures typically more than three standard deviations warmer than the local mean temperature for that period.

Another well understood feature of this warming will be a strengthening of the hydrological cycle because a warmer atmosphere can hold more water vapour. This tends to exacerbate droughts and flooding rains.

The table detailed below documents a series of extreme events over the past decade and the degree of confidence that these could be attributed to human-induced climate change. Many of these events are so outside the bounds of past experience that it seems there is a medium to high likelihood that global warming has contributed to the event’s severity.

Note: numbered references available from page 18 of the report

These extreme events, in conjunction with rising overall temperature, will take their toll on agriculture. While modelling prior to 2007 predicted some improvement in food production with warming of 1 to 3 degrees, according to the analysis, “research since 2007 is much less optimistic”. The report observes:

“These new results and observations indicate a significant risk of high-temperature thresholds being crossed that could substantially undermine food security globally in a 4°C world.”

The effect of 4 degree warming would be disastrous for coral reefs. Coral reefs would stop growing at a CO2 concentration of about 450ppm, which we’re well on the way to hitting within the next few decades. And coral reefs are at high risk of dissolving by around 2050 unless we seriously turn our emissions growth around.

Those who aren’t inclined towards conspiracy theories already know this is a serious problem. This report simply provides an exclamation point on the already apparent urgent need for action.

*This article was originally published at Climate Spectator



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35 thoughts on “Why 4 degrees will end the world as we know it: World Bank

  1. Mark Duffett

    Given geological evidence of coral reefs thriving at CO2 concentrations far in excess of 450 ppm, “coral reefs would stop growing at a CO2 concentration of about 450ppm” is probably an oversimplification. While currently dominant coral species begin to labour under these conditions, it’s certain that other, better adapted species currently restricted to niches will come to the fore. Reef systems as a whole will thus be maintained – if (and yes, it’s a biggie) there is enough time for the system adaptation to occur.

  2. Microseris

    Mark, I would prefer not to watch whole suites of species go extinct and wait for development of new ecosystems, just because we are too lazy and selfish to act.

    If it was war, who would argue about the personal sacrifice and action required or associated costs. However the potential outcomes look far worse than any war – a habitable planet.

  3. Al Black

    “It doesn’t make for pleasant reading.”
    Fortunately it doesn’t make credible reading either: the so-called research is just a rehash of dated and largely discredited IPCC material: The Himalayan glaciers are not melting, nor are the ice-caps on Greenland or Antarctica, and the Antarctic sea ice continues to grow: the exact opposite of what the IPCC models predicted. Polite Peer review articles say “the Antarctic ice spread has the effect of limiting confidence in the models’ predictions”. That means the World Bank is pontificating on outdated conclusions: What runaway warming?

  4. Merve

    Al, your claims should read “a few Himalayan glaciers are not melting, though most are, the ice caps on Greenland are melting faster than anticipated, the Antarctic sea ice is growing to a small degree with normal bounds, as expected, but the overall sea ice is shrinking dramatically. Overall, the global cryosphere is shrinking faster than expected”. Your statement is either wrong, or leaving out that you are looking at a few cherries amongst the global melt.

  5. Harry1951

    Al Black: pray tell what is your source for the “largely discredited IPCC material”? BTW, no one is talking about “runaway warming”. That reads suspiciously like a “straw man” argument to me.

  6. Observation

    Now I am skeptical. What is the world bank up to with this report. I smell a rat!

  7. Brent Hoare

    Isn’t it hilarious when some random anonymous internet guy chimes into a serious debate, and with a ridiculous rhetorical rant claims to know better than respected climate scientists, in this case the Potsdam Institute and a panel of eminent peer reviewers?

    Or it would be if the promotion of such wrong-headed ideas did not help to create the political space for the Opposition’s silly non-policy on carbon pricing and climate change.

  8. floorer

    “Poles apart: satellites reveal why Antarctic sea ice grows as Arctic melts”, copy and hit google and that will take you to the article in the Guardian/Environment/Climate Change section. No point putting up a direct link it will only go into moderation. Btw do you why the Arctics melting faster than the Antarctic? Because hot air rises, boom boom, all my own work can you tell?

  9. fractious

    Mark Duffett @1
    That ‘“coral reefs would stop growing at a CO2 concentration of about 450ppm” is probably an oversimplification’ is doubtless true.

    However, your claim “it’s certain that other, better adapted species currently restricted to niches will come to the fore” is similarly oversimplified. Where – given coral reefs are not contiguous – would these “other, better adapted species” come from? How would they migrate given that it isn’t simply a case of elevated temperature as a cause of their demise but sea level rise and (notably) rapidly falling oceanic alkalinity?

  10. Brent Hoare

    Mark Duffet @1 I suggest you go and read the report, and find some references that disprove the studies cited therein before making such sweeping generalisations. No wait, I’ll copy a relevant bit here for everyone:
    “Ocean Ecosystems
    “Disruption of the ocean ecosystems because of warming and ocean acidification present many emerging high-level risks (Hofmann and Schellnhuber 2009). The rising atmospheric carbon dioxide concentration is leading to rapid acidification of the global ocean. Higher acidity (namely, lower pH) of ocean waters leads to reduced availability of calcium carbonate (ara- gonite), the resource vital for coral species and ecosystems to build skeletons and shells.
    “The combination of warming and ocean acidification is likely to lead to the demise of most coral reef ecosystems (Hoegh-Guldberg 2010). Warm-water coral reefs, cold-water corals, and ecosystems in the Southern Ocean are especially vulnerable. Recent research indicates that limiting warming to as little as 1.5°C may not be sufficient to protect reef systems globally (Frieler et al. 2012). This is a lower estimate than included in earlier assessments (for example, the IPCC AR4 projected widespread coral reef mortality at 3–4°C above preindustrial). Loss of coral reef systems would have far-reaching consequences for the human societies that depend on them. Moreover, their depletion would represent a major loss to Earth’s biological heritage.” And it goes on…

  11. Bart Tony

    Our national paper “The Australian” chose to ignore this topic. Not one word has been printed about the World Bank’s report. Instead of investigating critical, relevant issues to all Australians and indeed all humans the “Liberal Party Gazette” is more interested in wasting news print on non issues such as Julia’s involvement in the AWU saga from which bugger all evidence has been produced.

  12. Achmed

    I think we can debate the rights or wrongs on global warming and there will never be concensus. Irrespective of the information put forward by both sides of the debate being credible or not has become in some ways irrelevant.
    All major political parties have a Carbon Plan to reduce carbon emissions. The debate is now about how the Liberals and Labor will take the money out of the pockets of the taxpayer. When you vote next year it will not be about whether or not climate is real or not. It will be about the whether or not polluters should be made to pay and Govt provide compensation by way of tax cuts etc or Govt giving taxpayer money out of the budget to the polluters.

  13. Nancy Peters

    What is going on in the world of climate change? Why have the IPCC not been invited to Doha for the first time in 18 years? Why is the US said to be downgrading the UN to a monitoring role only in climate change? Why is the emphasis being switched to the economics of the big emitters? Why has the World Bank prepared this report? I am confused.

  14. AR

    Hey, Tamas, any reassuring, rabble soothing words?

  15. Mark Duffett

    Brent, I am not convinced by Hoegh-Guldberg on this particular point. He extrapolates coral reef system destruction at the 450 ppm threshold from short-term, highly restricted experiments with artificially elevated CO2. This conclusion flies in the face of contrary geological evidence, to which he makes scant reference.

    While there uncertainties over what rates of change (as opposed to thresholds) are sustainable, the weight of evidence for mine is that coral reefs will prove more resilient than Hoegh-Guldberg believes.

    In any case, I hasten to add that this experiment (sustained global CO2 concentration > 450 ppm) is not an experiment we should be running, for a whole bunch of other reasons, even if it proves me right.

  16. Frank Campbell

    Global warming used to be cool. Every urban poseur from Margaret Simons to Hunter S. Rundle and Annabel Crabb genuflected in the Church of Armageddon. Briefly. Before returning to more pressing concerns.

    How things have changed in three years…Crikey, once a cauldron of climate hysteria, is now largely silent on the greatest moral challenge. Just the occasional outsourced professional propaganda piece like this one today.

    The hubris of the urban progressive is now archived, a memory stick of embarrassment. The Liberals didn’t split into impotence. There was no apotheosis of the Greens. The metrosexual banker swears allegiance to the simian priest. A corrupt and demoralised ALP, presiding over climate policy farce, couldn’t give a frack about global warming. The country clings to its fossil fuel export bonanza while killing off the renewable energy scams.

    Meanwhile, out in the Environment, rednecks flourish like noxious weeds. Operation Roll-back has begun. The fragile environmental gains of the past 30 years are being dismantled. Logging will restart in State Forest here a decade after it was killed off.

    No surprise that low postcode Crikey failed to replace the mass of climate hysteria verbiage with anything about the real environment…

  17. fractious

    It wouldn’t be a Crikey article on climate change without a Frank Campbell rant. But anyway, leaving your hysterical rhetoric aside, I fully agree with you on one thing – that the few, slender gains made for the environment made in the 70s, 80s and early 90s are being lost. Not “dismantled” as you put it, but clearfelled and bulldozed. A rash of COALitiion state guvmints and a weak federal environment minister, Fatty O’Barrell unleashing the feral shooters, extending cattle grazing rights in high conservation areas, signing off open cut and longwall mine leases as fast as the applications come through the door, CSG licences ten-a-penny, making election promises to ditch the “corrupt” Part 3A EP&A Act and replacing it with something identical… and that’s just NSW, I won’t even mention what’s going on north of the Tweed or south of the Murray.

    Whether you accept the facts of climate change or not, we will still be screwed if we keep up the rate we’re ra ping the environment.

  18. Liamj

    We at the voluntary human extinction movement applaud this progress report and look forward to another v.strong year, particularly from our flood, fire and famine divisions. Many thanks to our allies in denial, both the fossil fool denier camp and the tech dreamers.

  19. Frank Campbell

    But it’s people like you who got us into this mess, Fractious. Three years ago I predicted the current shambles, every fracking day, on this site. You call yourselves environmentalists, but you were seduced by climate extremism. This fascistic hysteria not only sent cane toads like Jones and Bolt into a spawning frenzy, it’s ruined any chance of intelligent policy on climate. The ridicule, ostracism and abuse directed at anyone who expressed the slightest doubt about climate Armageddon will never be forgotten. The intellectual dishonesty stinks like a fart in a lift.
    We need a new Greens party, and we need it now.

  20. Hamis Hill

    But single-issue conservationist extremism was never ever going to be ecologically sustainable.
    Not without also equally applying the International Greens Principles of Economic and Social Justice; Grassroots Participatory Democracy and Disarmament and Non-Violence.
    All too hard for the coalitions between Labor and the Wilderness Society, ACF etc, set up to cynically exclude those watermelons from political influence.
    To be inevitably overturned on the demise of Labor State administrations.
    In the meantime Abbott and Joyce destroy their Coalition’s ETS on the argument that single issue conservationist extremism is a heretical, planet worshipping religion enjoying a supernatural ascendancy owed to a deal with the Devil.( As preached by the good Cardinal)
    Abbott and Joyce carrying on ever since like demons called up from the depths of Hell to fight a fire versus fire end game against the red-greenies for the souls of the planet.
    Democracy being the sidelined antidote to such politico-religious dementoids as Abbott, Joyce, Pell TWS, ACF and other totalitarian chancers.
    Sorry, but you already knew all that, didn’t you?
    Stating the bleeding obvious again.
    Greenies Ain’t Greens!(Clue: Direct or participatory democracy; not on the greenie song sheet)

  21. fractious

    Not me Frank, I’ve been battling greedy developers, serial fibbers in state guvmints and opposing changes to environment and planning laws that screw our ecology and scupper community participation for 15 years or more (fat lot of good it did). As for climate change, as far as I’m concerned science is science, you might think you can pick and choose which bits of science you like and which you don’t, but IMO that makes you look silly. How polly ticks deal with the science is a whole other thing. On one hand the fed guvmint had to start somewhere, OTOH what’s been delivered won’t deliver any meaningful GHG reductions. What much of the last 10 years or so focus on climate has been very successful at is diverting funds and resources needed for conservation of terrestrial and marine ecosystems. Same with media coverage – just about every “environment” article in the MSM and here at Crikey in recent years turns out to be about climate change – it’s as if the dire state of our ecosystems is no longer worth mentioning.

  22. Karen

    @Frank Campbell – it’s quite clear you were completely hopeless at maths and science. Not to mention you pseudo intellectual dishonesty stinks like a fart in a lift.

  23. Frank Campbell

    The trollposts from Karen and Liamj show how incorrigible the Cult is…
    They stagger about in the wreckage of progressive politics,
    but no one’s listening to them any more.

    And at least we agree on one thing Fractious- the media focus on climate to the exclusion of everything else environmental…

    Lovelock has apologised (his name never mentioned since his recantation- airbrushed from history by the Cult), and Lomberg is the new guru of choice for recovering climate fanatics…

  24. Ian

    Lets face it we have a problem…sorry, many, many problems and climate change in the medium to longer term is the mother of all problems but we are also rapidly running out of all sorts of resources, oil, fish and phosphorous to name but a few. Yes and the environment is being wrecked here in Australia and elsewhere.

    At the same time we have a peak debt problem. About the only thing not in short supply at the moment is money which they keep printing and feeding to the bankers, the military and so forth but not to you or I.

    We have the US and allies running wild looking to satisfy the needs of the military/industrial complex and we have the mainstream press ignoring or trivializing these problems and creating a culture of selfishness, ignorance and apathy.

    To be fair on Crikey, at least they do cover most of the issues in a more enlightened way but what we are all neglecting to discuss is why the problems continue and are, in fact, escalating. There is no simple answer to that but perhaps a start would be to recognize that our capitalist system is broken and our major parties as well as those in the the rest of developed world refuse to let go of it.

    We must realize that the relentless pursuit of growth, trickle down economics and the “free market” controlled by corporate monopolies or oligopolies will have a sad ending. I began to recognize the problem around about the time of the failed Copenhagen climate summit and events since then have reinforced my belief.

  25. Ian

    My comment is under moderation. Why?

  26. wyane

    let’s just go full pelt and let the 800 million luckiest people deal with the scraps next century. oh yeah. we already are.

  27. Hugh (Charlie) McColl

    Frank Campbell, electricity demand is down. Someone is listening.

  28. Frank Campbell

    Now I wonder why demand is down, Hugh. Let me guess. Doubling the price might have something to do with it, and the 10% carbon tax impost on power will further depress demand.

    Mild conditions and continued de-industrialisation also have something to do with it, right Hugh?

  29. Liamj

    How dare Frank Campbell allege i am involved in progressive politics, out here in the sticks nobody mentions politics or the climate, ever. Lot of talk about the weather tho, and some blo ody early fires..

  30. fractious

    Frank, take a minute out from the polemic will you. Even I – a political ingenue according to you – has joined the dots. If you campaign to save terrestrial, aquatic and marine ecosystems, you by default help preserve carbon sinks. Conversely if retaining and augmenting terrestrial and oceanic carbon sinks is a significant part of reducing atmospheric GHG emissions then by default some (admittedly not all, and certainly not all endangered) ecosystems are valued and retained.

    Not “win-win” (to use a revoltingly trite phrase) but certainly acknowledging the one is intimately and intricately linked to the other. In a world of ever-increasing population and resource extraction, ya gotta take what ya can git.

  31. Frank Campbell

    I must have misunderstood your satire, Liamj…

  32. Frank Campbell

    Polemic is fun, Fractious, but just for you I’ll desist for a moment…

    Your argument is precisely what I’ve said since the birth of the cult. We had to channel/placate the ferocity/energy of the millenarian cult- because it had for a few brief years the power of Savonarola. The idea was to tie every “carbon” policy to environmentalism- i.e.make every “carbon” policy consonant with environmental policy. So that even if the entire CO2 theory turns to dust, we’ve still gained. This strategy has been a total failure: the policies adopted have been irrelevant or inimical to the real environment. Whether it be the carbon tax or wind turbines or geothermal, the policy (and often implementation) has been counter-productive. Politically, the battle is almost lost.

    As I say often- the carbon cult is its own worst enemy. It’s failed to make any constructive use of the power it once had, and its fascistic stupidity is delivering us into the hands of the hard Right, rednecks, feral corporations etc.

    So the natural carbon sinks are being screwed a bit more every year…Even in 20 years I’ve seen a marked decline in species abundance in the areas I know- areas with no apparently “new development”. We’ve slowly gone backwards for the past decade. The next decade will be a lot worse, unless we can kill the cult in order to target the enemy, which is our old friend, corrupt, rapacious corporate capitalism.

  33. Liamj

    Thats okay Frank, i don’t get yours either. 😉

    It is true that habitat loss/biodiversity/persistant toxics/asbestos/radiation/lead/etc (all the ‘little’ problems) have dropped even further down the to-do list, but we were never more than pretending to care about those problems anyway, just like we pretend (5% ?? pfft!) about anthropogenic global warming.

    What those issues lack is AGWs easy faith. One can accept AGW and simply conclude that those at fault lie far away (eg. China), and then get on with BAU in the meanwhile. No messy lying in front of machinery, tedious meetings, or personal change required!

  34. Ian

    Frank,you say:-

    “A corrupt and demoralized ALP, presiding over climate policy farce, couldn’t give a frack about global warming. The country clings to its fossil fuel export bonanza while killing off the renewable energy scams.” I agree but not the scams part. But frankly the rest of your stuff is… shall we just call it crap and leave it at that.

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