climate change
26 Mar 2008
What Happens After 2030?
If climate change is even partially as destructive as we suspect, our notion of national sovereignty is about to be challenged by new forces, writes Julie Macken
When the world renowned climate scientist, James Lovelock, declares that catastrophe is inevitable and the world's population will be reduced by 80 per cent by the end of this century, it is probably time to think about either heeding his advice and partying hard, or spending what time there is left trying to achieve a different outcome.Unlike Lovelock's prophesy, the language of the Intergovernmental Panel on Climate Change (IPCC) reports is by necessity cool and calm. The numbers, percentages and statistics suggest an imaginable world of cause and effect, a future and a planet we can all do business with - after we've switched to renewable fuel and planted a few more trees.
This is not to suggest the authors of the reports are relaxed and comfortable about what their modelling tells them. As the Bali Declaration suggests, quite the opposite is true.
No, the illusion of manageability and containment is maintained by our collective refusal - or inability - to front up to the implications of the numbers. How much hope do we hold for adoption of the 90 per cent emissions reductions recommended by the Garnaut Climate Change Review? And further, given there is now at least a 1.7 degree increase in temperature built into the system, whatever we do about carbon emissions, how will China, India and Africa feed their people? And with the projected decrease in rainfall, loss of glacier run-off and increase in evaporation, where will their water come from?
For some, these are questions for today, not tomorrow. For the Dalits of India, the Rakhain fishing community in Bangladesh, the pastoralists of Kenya and the Afro-Colombians in Colombia, climate change is already a brutal reality they are struggling to live with. As are the citizens of Tuvalu, Darfur and Uganda, who are already dealing with water supplies contaminated by saltwater, reduced herds due to drought and, in Darfur, a resource war that is daily redefining horror.
The time is fast approaching when the West too will struggle with the impacts of climate change on access to resources we take for granted. Unfortunately, history teaches us that if we wait until resources are stressed or disappearing, despair and fear will determine our actions, not our collective will or humanity. Therefore the time for thought, reflection and action is now.
Having finally rejoined the international community last December, Australia will spend the next two years locked in climate change negotiations to create a post-2012 agreement. The Rudd Labor Government has said it wants an international agreement that is "equitable and efficient".
This is all to the good. The carbon dioxide content of the world's atmosphere is now at 385 parts per million (ppm). To have a 50/50 chance of avoiding more than a 2 degree increase in the world's temperature, the carbon in the atmosphere needs to not exceed 450ppm. However, with all the indicators going in the wrong direction - carbon emissions are not declining or even stabilising, but rather surging - the chances of achieving stabilisation at 450ppm is extremely unlikely.
This is why the post-2012 international agreement, while important, needs to be run in parallel with the development of international agreements that assert and reinvigorate the basic human rights of all citizens, whether their particular nation state survives the coming climatic conditions intact or not.
Current scientific modelling draws into question the ongoing viability of many nation states in light of a 2 degree plus global temperature increase. Examples of some projected regional impacts by the IPCC include:
Africa: by 2020, between 75 and 250 million of people are projected to be exposed to increased water stress due to climate change. By 2020, in some countries, yields from rain-fed agriculture could be reduced by up to 50 per cent. Agricultural production - including access to food - in many African countries is projected to be severely compromised, exacerbating food security and malnutrition. A situation the citizens of Darfur know only too well.
Asia: by the 2050s, freshwater availability in Central, South, East and South-East Asia, particularly in large river basins, is projected to decrease. Coastal areas, especially heavily populated mega delta regions in South, East and South-East Asia, will be at greatest risk due to increased flooding from the sea and, in some mega deltas, flooding from the rivers. Climate change is projected to compound the pressures on natural resources and the environment associated with rapid urbanisation, industrialisation and economic development.
Europe: climate change is expected to magnify regional differences in Europe's natural resources and assets. Negative impacts will include increased risk of inland flash floods and more frequent coastal flooding and increased erosion (due to storms and sea level rise). Mountainous areas will face glacier retreat, reduced snow cover and extensive species losses (in some areas up to 60 per cent under high emissions scenarios by 2080). In southern Europe, climate change is projected to reduce water availability, hydropower potential, summer tourism and crop productivity - and increase heat waves and the frequency of wildfires.
Latin America: by 2050, increases in temperature and associated decreases in soil water are projected to lead to gradual replacement of tropical forest by savannah in eastern Amazonia. There is a risk of significant biodiversity loss through species extinction in many areas of tropical Latin America. Productivity of some important crops is projected to decrease and livestock productivity to decline. Overall, the number of people at risk of hunger is projected to grow. Changes in precipitation patterns and the disappearance of glaciers are projected to significantly affect water availability for human consumption, agriculture and energy generation.
It is the human response to these projections that will drive the destabilisation of international relations and test our collective capacity for co-operation. This is why the human rights system has so much to offer by way of preventative work - and why the science needs to inform the development of a reinvigorated and globalised human rights agenda.
If climate change is even partially as destructive as we suspect, the foundation of national sovereignty - territorial integrity - is about to be challenged by new forces.
Previously, territorial integrity was at most risk from armed forces. But the nation state may now be at risk from natural forces and the response of its citizens. The nation state and its population may be transformed by climate events that make the state meaningless, reducing social groupings to collections of individuals.
In such circumstances, we need to ask ourselves: who becomes responsible for the preservation of human rights?
The International Covenant on Economic, Social and Cultural Rights, the International Covenant on Civil and Political Rights and other treaties and human rights norms which have acquired the status of customary international law and jus cogens provide important guidance on how we need to think about the basics of life.
The marriage of science and human rights discourse has posed many challenges - particularly recently where genetic technologies race ahead of ethical and rights discussions - but a strong working relationship union between the two is necessary now.
As Professor Nicholas Stern suggests in his response to the Productivity Commission's criticism of his Report: "Notions of rights, duties, vital needs and the virtues may all be relevant to the crucial question of what we 'should' do about climate change. More research, and the involvement of moral philosophers, would be welcome in this area."
Indeed it would.
This article has been updated from its original form for accuracy.
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Oh no! Not the nation-state! Damn you environment! Is there nothing you can leave unchanged?! I guess we’ll need to have a ‘war on carbon’ soon! Smoke that carbon out of its hole…
…But seriously…
"The marriage of science and human rights discourse has posed many challenges…"
According to whom? I see only a persistent complementarity between the two.
"…the involvement of moral philosophers, would be welcome in this area."
I’m not aware of any "moral philosopher" willing to stick their proverbial neck out for the type of ‘human rights’ the article seems to be advocating. Regardless of what Mr Stern may believe, we are not forever engaged in replaying the Scottish Enlightenment.
Nation states have HUGE resources and momentum. A lot of other things will change before they do … communities, industries … nation states will probably be the last concept standing.
Actually, there was at least one major philosopher who focussed on the links between human responsibility and the environment, Hans Jonas. Look him up on Google.
Joe
fluff4
Hi joe
Since reading this man, global warming is off my radar.
http://www.middlebury.net/op-ed/global-warming-01.html
Reading his qualifications to comment too has put my mind to rest, as I believe it would for the posters here’s about. If you too need a rest from the terror being promulgated I suggest you read the article written by a retired climate expert.
It is long but not tortured. Unlike me you may comprehend the maths
nuff to say his claim "the atmosphere max’s at 8% CO2"
fluff
Joe,
Hans Jonas, eh? Mr ‘imperative of responsibility’ Himself.
If you can show me how the much lauded ‘imperative of responsibility’ translates into a pragmatic human rights regime, I’ll eat my hat. (Note the ‘pragmatic’ condition)
Jonas epitomizes fear. That’s probably why he was so popular in the perpetually terrified element of the German psyche, and probably why more generous reviewers often group him with Hegel. It is definitely why politicians interested in drumming up support appropriated his language. His premise is itself unoriginal, and it is also the premise of conservativism: we don’t know, so we should be careful. This is a poor universal principle. (Its actually completely congruous with the universal principle of consumerism - buy now, pay later = because you never know what could happen!)
I prefer ‘dare to think!’ Or, ‘have the courage to use your own reason!’
Environmental solutions are pragmatic, and require a moral orientation that is pragmatic. Solutions (and we are talking about solutions) are not universal, so there is no need for any inalienable environmental rights (or responsibilities) of man (or womyn).
Kudos though Joe, on actually taking the discussion somewhere…
As I understand him, Jonas maintained that ever since human societies came into , over the millenia, they have developed technology to ‘manage’ the environment, i.e. get sustencance from it, and this technology in turn conditioned the development of culture: that this development in knowledge (with off-shoots and abandonments) is cumulative, that it rarely is reversible, that it shapes culture and further technology symbiotically but inexorably - to the point now across the world where human societies are responsible for technological activity and developments on a scale, and with all sorts of unforeseen possible consequences, that force us to, yes, be fearful of what we can achieve.
Therefore, like it or not, we have responsibility to be extremely careful now and into the indefinite future how we act on the environment, how we modify it, how we try to ‘correct’ it as a consequence to the generations of pollution and now climate change (to the extent that it is genuinely occurring as a result of human activity). Why should we care ? Because, as Jonas (as a Jew with very powerful memories of the mortality of humanity: read his wonderful article about the fallibility of God), would say, the environment belongs to the future, it must be sustainable in supporting the unavoidable burden of us, humanity, for generations now and those in the future.
Maybe I’m reading too much into what he writes but I don’t see anything particularly wrong or bad about being so mindful of our awesome responsibilities (and those of our descendants) that we are fearful - it’s not a bad emotion to feel on behalf of the planet, rather than the smugness that will infuse so many (dare I say it?) young people tonight when they turn out the lights for an hour and wander around, all excited, with multitudes of candles: they will have done their bit for another year.
I think that Jonas is saying that environmental responsiblities will be with us forever, and to the extent that fear comes into it, we need to be fearful for our grandchildren’s sake, and theirs.
Back to Julie Macken, guys…
Foundations of the nation-state are about to be challenged…right.
Refusal or inability to face up to the numbers… right.
Fear and despair likely to determine our actions… right again.
But I am skeptical of a way out via ‘human rights recognition’.
Why? The charters etc. we are familiar with are usually drawn up
and pondered by those whose rights are NOT under threat. In this case, NOT SO!
The situation is likely to be more akin to the world of Mutually Assured Destruction (remember the MAD nuclear 1980s?)
And this is not a Singapore ‘42 type alarm; rather, it’s a ‘frog in the slowly heating pot’ scenario.
If it were not that the leadership and populations of the world’s ‘educated’ citizens looks set to wake up too late to stop the runaway rise in temperature, we’d be lucky in that the rights under threat would be seen to belong to ALL, including US - inducing measured, fair and forthright action…because anything less would risk the other guys stuffing up OUR future, through non-cooperation with universal regulation to reverse the climbing carbon count.
It’s not rights the frog needed, it was awareness. We are the frogs, right now. How long till fear breaks out?
No, we are not going to be condemned to forever play out the Enlightenment.
It is highly likely that long before 2030 the people will have recognised and will no longer put up with the likes of Julie Macken and her ilk endlessly promoting, in the name of a post modernist, scandalously selfish moral philosophy, their own MAD - Massively Apocalyptic Destruction scam.
It is also likely that long before then we will have faced up to dealing pragmatically with the modest degree of climate change that MIGHT be occurring.
http://www.rocketscientistsjournal.com/2007/06/on_why_co2_is_known_not_t…
http://moderatesunited.blogspot.com/2008/03/climate-change-issue-simplif…
Of course, there are a hell of a lot of environmental issues besides global warming to worry about, and have been for a long time now. Salination, deforestation, desertification, pollution of waterways and ground-water and the oceans, etc. And yes, most of us might be like frogs in a pot if we don’t work out ways to manage these environmental problems, and resolve them if possible. But it will be up to us, putting pressure on governments, to turn things around - the Murray-Darling situation is a good example. Can the people of the world, the frogs in all of the various pots, coordinate and organise effectively enough to control these problems ? Or do we throw our hands up and talk of MAD ? Was Hanrahan right ? Are we all doomed ? Or is this the easy way out ?
Joe
"but I don’t see anything particularly wrong or bad about being so mindful of our awesome responsibilities (and those of our descendants) that we are fearful"
Sorry Joe,
But I see everything wrong with being so mindful of our awesome responsibilities that we are fearful. This sound like dogma to me.
Being against the universality of the precautionary principle is not the same as being against the precautionary principle universally.
I challenge anyone to a discussion of specifics. Show me how you think the precautionary principle should be applied. Be specific: to what, where, when, for how long, who will be affected, who will benefit etc. etc.
"It is through pragmatic discussion that change is wrought, so
it is in pragmatic terms that we should frame our thought."
The resentment driven howls of universal this, transcendent that, serve - like comfort food or a cigarette - only to temporarily numb the reality of one’s predicament.
Hi Bob,
Thanks for your circuitous reply. Mindful, fearful, precautionary, x - I don’t care what you call it, surely we should all be x, given the demands of six billion people, us, on the environment, the only one we’ve got, and the fearful power of modern technology, us, to take more from it than it puts back. Fearful - and permanently fearful - seems to do it for me.
Specific: cut back on demand, use less, recycle, devise comfortable ways of going without; cut back on use of resources, alternative energy, recycle resources like water.
Cheers,
Joe
So, ecoeng, you concede there MIGHT be a "modest degree of climate change occurring".
With all the lack of awareness that’s about, and not a little conscious issue-avoidance by some elected leaders, the planet needs denialists just for variety’s sake?
Stop ignoring what the science is saying and concede that most experts agree there’s a huge problem looming, and that the vast majority of them aren’t ego-tripping.
Of course there is bloody global warming - not necessarily by human activity, but I wouldn’t bet against that. Yes, it might be sun-spots. Either way, do we sit on our arses and complain, or nit-pick, while the planet burns ? Either way, we have to act, certainly to minimise human effects on the environment, no matter who is to blame (you are ! no, you are ! no, you are ! I’ll tell my father on you, and he’s a policeman ! I don’t care, nyah nyah !)
So what do we do, children ? Switch to renewable energy, fish-farm, re-cycle, economise, clean up the oceans, of course, among other things. Get dirty industries off the planet, not just out of our backyards. Take Phillip Adams’ advice and paint everything green: that would be as much use as your pissy arguments about who did what. Be mindful of the damage we are doing and will continue to do, by our very existence, and try to minimise it.
Joe
A new book ”The Deniers’, examines what should still be active debate concerning the degree to which human CO2 emissions (or CO2 per se) is a driver for significant climate change, what role the solar wind and cosmic ray flux may play in climate, what role the present warming trend (and human activities) play in hurricane and tropical/parasitic disease patterns, and the reliability of the General Circulation Models (GCMs), amongst other issues.
Many scientists have endured harsh treatment simply because they followed the scientific method, the evidence from their research, and their own consciences, all of which led them to the conclusion that this or that facet of the global-warming consensus view was woefully incomplete or flat-out wrong. This treatment has had the effect intended by global warming scaremongers — to shut down promising areas of research and to silence credible critics.
The term ‘sceptic’ has historically been a badge of honor proudly worn by scientists as indicating their commitment to the idea that in the pursuit of truth, nothing is beyond question, every bit of knowledge is open to improvement and/or refutation as new evidence or better theories emerge. However, in the upside down field of climate science, “sceptic” has become a term of opprobrium and to be labeled a sceptic is to be dismissed as a hack.
Being a sceptic concerning global warming today is akin to being a heretic in the Middle Ages — you may not be literally burned at the stake, but your reputation and integrity will be put to the flames. This is largely because of the high degree of ignorance of basic science held by those who have bought the whole ‘global warming is an apocalypse just around the corner package’ hook, line and sinker.
Many scientists whose research calls into question one or more of the fundamental tenets of global warming orthodoxy, have learned to couch their conclusions carefully. They argue, for instance, that while their research does not match up with this or that aspect of global warming theory, or would seem to undermine this or that factor, they are not denying that humans are causing global warming and they cannot account for the discrepancy between their work and the theory’s predictions. These scientists have learned the hard lesson that when reality and the theory conflict, for professional reasons, they’d better cling to the theory: a replay of Galileo recanting his theory that the earth revolves around the sun under pressure from the Catholic Church’s Inquisition.
Though there are many good books on global warming, The Deniers is effective in showing how the integrity of science is being fundamentally undermined in the current politicized atmosphere of climate research. In addition, it provides a concise but thorough overview of the many technical weaknesses of the so-called consensus view, the quality and depth of the criticisms of that view, and the outstanding technical qualifications of most scientists labeled derisively by the ignorant masses as “deniers.”
This book should be read by anyone with an open mind who seriously wants to understand where and why substantive debate still remains concerning the degree of anthropogenic climate change and why there is now so much vitriol surrounding what until recently was a relatively quiet, unheralded, or unnoticed (except by its practitioners) field of science.
I rest my case. Yes there is global warming. Let’s do something about it, however it is caused, instead of thinking we have resolved anything by blaming human activity.
Real world observations of the climate response to recent volcanic eruptions suggest that the earth’s climate sensitivity is quite a bit less than the sensitivity predicted by GCMs. Observations suggest that the sensitivity lies near or below the low end of the IPCC4 range of 1.5 to 4.5ºC for a doubling of CO2.
The lower the climate sensitivity, the lower the potential future temperature rise, and the lower the potential impact. This is precisely the same conclusions that one arrives at when relating observed temperature changes to other observed quantities such as carbon dioxide emissions or carbon dioxide concentration.
Even James Hansen, the ‘godfather’ of global warming is now taking this position. See here for example:
http://www.worldclimatereport.com/index.php/2004/04/14/observations-not-…
As time goes on, and hard scientific research continues, it is becoming clearer that the high end of the range of temperature increases projected by IPCC4 is simply scientifically unsupportable. All the while, the evidence mounts which suggests the low end is the more probable outcome.
Douglass, D.H., and R. S. Knox, 2005. Climate forcing by volcanic eruption of Mount Pinatubo. Geophysical Research Letters, 32, doi:10.1029/2004GL022119.
Michaels, P.J., and P.C. Knappenberger, 2000. Natural signals in the MSU lower tropospheric temperature record. Geophysical Research Letters, 27, 2905-2908.
Santer, B.D., et al., 2001. Accounting for the effects of volcanoes and ENSSO in comparisons of modeled and observed temperature trends. Journal of Geophysical Research, 106, 28,033-28,059.
Wigley, T.M.L., 20000. ENSO, volcanoes and record breaking temperatures. Geophysical Research Letters, 27, 4101-4104.
Wigley, T.M.L., et al., 2005. Effect of climate sensitivity on the response to volcanic forcing. Journal of Geophysical Research, 110, doi:10.1029/2004JD005557.
In effect, we are now being asked to believe in an ‘Apocalypse Soon’ by professional doomsayers (otherwise known laughingly as ‘climate change consultants’), most of whom don’t even have a hard science degree, on the basis of un-validated mathematical models they couldn’t even understand themselves! RIRO - rubbish in, rubbish out.
ecoeng, you point to the "…current politicized atmosphere of climate research" but then admit there’s "…so much vitriol surrounding what until recently was a relatively quiet, unheralded, or unnoticed field of science".
Surrounding - yes. Obviously. But I’d assert that accusations of ‘bad science’ thrown by denialists just fly in the face of all those verifications of what we are into by 000’s of experts not out of loopy colleges in the Deep South.
You just give oxygen to the populist media to go on whipping up controversy where there no longer is any.
"But I’d assert that accusations of ‘bad science’ thrown by denialists just fly in the face of all those verifications of what we are into by 000’s of experts not out of loopy colleges in the Deep South."
Would you now! I’d say that "…not out of loopy colleges in the Deep South." sounds remarkably like vitriol to me. There are a number of good universities in the ‘Deep South’ of the US just as there is one (James Cook Uni) in the Far North of Australia which houses a prominent, mainstream sceptic (noting the term ‘denialists’ is for the immature). It also sounds to me like you have been mentally too lazy and/or insufficiently educated to examine the so-called consensus for yourself.
There’s a little vitriol thrown back at you.
You also don’t seem to have noticed that I try to reference everything I assert - in particular wherever possible from the (non-loopy) mainstream, peer reviewed scientific literature. This is only natural given that I am a mainstream earth scientist myself with approximately 60 peer-reviewed journal papers and book chapters. How about you exhibit the guts to make some concrete statements in relations to the matters I have posted AND do the same?
Then we could try to debate the matter at an adult level.
fluff4
ecoeng
Thanks for posting your quals to comment. if support is needed read
http://www.middlebury.net/op-ed/global-warming-01.html
I would be interested in your comment, critisim, whatever. I’m no scientist and have been reading myself blind trying to understand the truth on this subject, "Dad" has explanations that clearly don’t try to confuse, you may also comprehend the maths presented. please post your opinion, his quals too are impressive.
regards fluff
Surely the crucial issue is:
Is global warming occurring ? Yes ? No ?
A much less important issue is: is human activity to blame (rather than sun-spots or the will of God) ? But it’s more fun and if we can find something to blame, then we are off the hook: it’s all capitalism’s fault, or religion’s, or China’s, or somebody else’s. But no, stuff whose fault it is - it’s all our problem. What do we do about it ?
Joe
fluff4
No Joe it ain’t
http://www.middlebury.net/op-ed/global-warming-01.html
fluff4
I am happy the lay my cards on the table.
Is global warming occurring ? Yes ? No ?
Is human activity largely to blame? Yes, No?
In my view, considering as much scientific literature as my spare time will permit, I think the answer to the 1st question is Yes and to the 2nd, Maybe.
I also take the view that a really important question is: How much global warming is likely to be produced over the next several hundred years if the level of atmospheric CO2 doubles (the so-called sensitivity). Only when we know, as accurately as possible, how much trouble we are in for can we plan and implement measures relating to human civilization (not the only issue) on appropriate timescales.
Again, in my view, on the same basis described above, I conclude the current best estimate is a rise of the order of 0.5 - 1.5 degree with (again in my view only) a current best estimate around 1.0±0.25 degree at about the one standard deviation level.
I have two overarching problems, as follows:
1) Decisions relating to AGW and atmospheric CO2 buildup are possibly the biggest decisions mankind has had to collectively face. I don’t like the Apocalypse Now bandwagon because very few wise decisions get made under states of Panic, Fear OR Excessive Group Think. Look at the ‘Warrior Religions’ (still around to bu us ‘dog’ damn it), Nazi Germany, the Iraq War etc. etc. (ad nauseam). I also think that the whole concept of ‘consensus’ in Science is essentially a crock of ……. No good scientist I’ve ever known really buys that concept.
2) While we are getting hyped up about radically controlling human CO2 emissions in the near term, I very much fear (from the literature) that we are missing critically important wider issues and effects. I refer to issues such as insufficient understanding of the true nature of the Sun, terrestrial climate, the (all important) oceanic CO2 conveyor i.e. the power of the sub-polar cold water bands to scrub physically and chemically CO2 from the atmosphere, including the effects of surficial acidification on the health and mass of the planet’s standing crop of oceanic cyanobacteria (NB: the biggest component of the global biomass). There are strictly no GCMs which consider all these and to that extent they are still quite primitive tools.
More than ‘nuff for now.
After I posted this (in a hurry from work - sorry about the typos) it struck me that most intelligent New Matilda readers should really be able to calculate this out for themselves. Then they can truly decide for themselves whether the alarmist claims of people like Julie Macken, Christine Milne etc are justified.
All you will need for this calculation is a simple mortgage or investment appreciation calculator. It goes like this.
Let us use 1990 (i.e. the Kyoto baseline year) as our convenient start point. In 1990 the average atmospheric CO2 level at Australia’s Cape Grim station was 351 parts per million by volume (ppmv).
www.environment.gov.au/soe/2006/publications/drs/pubs/274/atm/a_07_green…
The web-published Cape Grim record also shows that CO2 levels have been rising by 0.46±0.16%/year over the period May 1976 - November 2004. BTW, the ± figure is the uncertainty at the ± standard deviation level i.e. there is a 67% probability that the true value is within that ± band.
Don’t ask me why they can’t possibly keep their published spreadsheet up to date to at least the end of 2007 - maybe they don’t really care about all those poor, sleepless, deeply alarmed, non-scientific mug punters out there (;-).
Using your mortgage or investment calculator, setting the mortgage or investment to (say) $351 and the interest to 0.46±0.16 %/year (i.e. use separately 0.30 and 0.62%/year) you will be able to show that your $351 investment or mortgage doubles to $702 in 151+80, -39 years i.e. 112 - 231 years. Therefore the 1990 atmospheric CO2 level of 351 ppmv is predicted to double in somewhere between 112 - 231 years from 1990.
It is well known and agreed certainly by all AGW adherents that the relationship between global atmospheric CO2 and global lower atmosphere (troposphere) temperature is a log-linear relation i.e double the CO2 and you push up the temperature by a fixed amount. This is a consequence of the bulk physics of the whole process. For a CO2 doubling the temperature rise is called the ‘sensitivity’ (just another geek term). The key issue is just what is that CO2 ‘sensitivity? IPCC4 says 1.5 - 4.5 degrees.
So the question is: what is the temperature rise likely to be 112 or 231 years from 1990 (i.e. in the years 2102 - 2221)?
It is generally agreed that global temperatures rose by approximately 0.7 degrees between 1890 and 1990 i.e. approximately 0.070 degrees per decade.
However, AGW alarmists also say things like; that rate had increased to about 0.082 degrees per decade by the end of the 20th Century, citing e.g. evidence from 460 stations between 60 and 90 degrees south (i.e. between Patagonia and the Pole) from 1958 - 2002. However, DESPITE the ‘Inconvenient Truth’ that almost all of this temperature rise occurred in a small area around the (volcanically active) Antarctic Peninsula:
Chapman, W.L. and J.E. Walsh. 2007. A Synthesis of Antarctic Temperatures. Journal of Climate, 20, 4096-4117.
let us ignore such ‘minor quibbles’ and actually use this higher (0.082 degrees/decade) figure. This, by the way, for the Julie Macken’s of this world, would put the global average temperature in 2030, only 22 years from now, up by a whopping 0.18 degrees!
However, the real question is: What would the temperature rise be, by as early as 2102 (for a maximal CO2 increase rate of 0.62%/year) or as late as 2221 (for a minimal CO2 increase of 0.30%/year) if we were unable to stop the CO2 doubling from the 1990 level to hit 751 ppmv?
The answer is of course 0.92 degrees in 2102 for the faster CO2 increase rate (0.62%/year) and 1.89 degrees in 2221 for the slower CO2 increase rate (0.30%/year).
So, what is the bottom line? It is this.
Unless the AGW alarmists have some super duper private data which enables them to say that, more recently than 2004, the average rate of CO2 concentration increase in the lower atmosphere has been, or will be more than say 0.62%/year then it is highly unlikely that world temperatures would be more than about 1 degree above where they are now in 2100.
However, this ‘special knowledge’ would require NOT ONLY a massive increase in current global CO2 emissions rates BUT ALSO significant failure of the ‘Oceanic CO2 Conveyor’ which takes CO2 into cold sub-polar waters, moves it through the ocean currents and spits most of it back about 1400 years later on average from warm equatorial waters. We may be comforted by the fact that this ‘Conveyor’ has successfully lived with atmospheric CO2 levels as high as 2% (20,000 ppmv) in the past without destruction.
I have previously noted that the ‘father’ of global warming James Hansen was supporting an estimate of a 0.75 degree rise by 2100 as early as 2004.
I don’t think Hansen has revised that position since then - particularly in the light of what has happened to world tropospheric temperatures between 1998 and 2008 i.e. a slow cooling - another ‘inconvenient truth’ which further erodes the best estimate of the average CO2 sensitivity value.