Bishop Hill Green spouts on drought
Aug 8, 2011 Climate: WG2 Duncan Green is head of research at Oxfam GB and has written an article exploring the question of whether the drought in the Horn of Africa is caused by climate change. The article is here and an edited version appears at the Guardian. I'm sure that comment will be freer at Mr Green's place.
Green presents evidence to support the idea that the drought in the Horn of Africa is global warming in action: anecdotal evidence from the locals and increases in surface temperatures. He also notes rather more importantly that the rainfall records are ambiguous.
He then goes on to look at the models:
Globally, climate change modelling projects an increase in the frequency and severity of extreme weather events like droughts and floods. In the absence of urgent action to slash global greenhouse gas emissions, temperatures in the region will probably increase by 3°C-4°C by 2080-2099 relative to 1980-1999.
As we can see, Mr Green skirts over all the uncertainties in the IPCC storylines and portrays no sense of just how tentative the conclusions about extreme weather events are. This is par for the course for political campaigners, I suppose.
The models also suggest that rainfall will increase in a warming world. This being the case, one should presumably conclude that drought is not an issue we should worry about. This is, however, another issue that Mr Green chooses not to discuss.
Reader Comments (49)
I think that the general conclusions of all the modelling is no better than:
'It'll be dry where it doesn't rain, but where it rains it'll be wet'
Perhaps Richard Betts or another climate scientist can correct me if the 'predictions' are actually any better than I have represented them. References to where such predictions are easily accessible outside academe (i.e. to private individuals without journal subscriptions) would help.
If he can show how a fractional increase in a trace gas drives ENSO he'd have a point, otherwise not so much.
The Oxfam "background briefing" his opinion seems to be based on is downright schizophrenic, it identifies the main causes such as "entrenched poverty due to marginalization, conflict and lack of investment."..." this crisis has been caused by people and policies, as much as by weather patterns. An adequate response to the current crisis must not only meet urgent humanitarian needs, but also address these underlying problems."
but the recommendations are all "To avoid catastrophic levels of global warming:"
Hello Oxfam... HELLO...
Just £2 per month
Oxscam
I kept wondering how long it would be before some-one tried to blame the drought on AGW, now i know!
I wouldn't trust any "research" coming from Oxfam, Greenpeace, WWF, FoE or any other politically-motivated environmental pressure group. The BBC trusts these organisations without question.
There's a lot of waffle along the lines of "some say tomarto but a recent study says tomayto".
Underneath the babble, the underlying theme seems to be a bizarre circular argument:
This is a new type of fallacy but it's already got a name: it's called the "wet pavements caused by wet pavements" argument*.
*Micheal Crichton identified the "wet pavements cause rain" fallacy.
Judith Curry links to a post by Andy Revkin on the same question of whether the famine/drought can be blamed on AGW. Whenever she discusses attribution of extreme weather to AGW (e.g. in this recent post), Judith is fairly dismissive of the idea that there is any detectable "signal" of global warming in current weather events. I see also that the Oxfam post links to the Myles' Fludd Nature paper in support of the statement that "there are now a few cases in which scientists have been able to estimate the extent to which man-made climate change has made a particular extreme weather event more likely". At the time that the Myles' Fludd paper appeared, Judith wrote about it: "I find this kind of analysis totally unconvincing."
/Quibble Mode on
Bish, The question posed is actually - 'So is famine in the Horn of Africa linked to climate change or not?'
Since the article includes the line - 'Firstly remember that while the drought is caused by lack of rainfall, famine is man-made.'
The answer would seem to be - 'No.'
/Quibble Mode off
That said, it manages to get there via such gems as - 'The current drought conditions have been caused by successive seasons with very low rainfall.' Who'da thought it?
Many years working in Africa led me to decide to never again put a penny in a tin on the high street. I often wonder what damage has been done to the tin shakers efforts by people such as Duncan Green.
The oft made mistake by the Greens is they automatically think the sceptics do not care about the environment. Take that viewpoint along with the "we know better" attitude and you have a disaster when it comes to raising funds, as many Greenpeace/WWF etc tin rattlers have found out in the last few years!
It is interesting how Green used "The historical record does not ‘prove’ that the current drought is directly attributable to climate change" in his argument and then goes on to use models that...are not really proving anything.
The one thing that makes me smile is what you picked up on Bish...
"But again, rainfall projections are unclear. Most modelling, as reflected in the IPCC’s last assessment, suggests more rain will fall in the East Africa region as a whole, with an increase in ‘heavy events’ (sudden downpours, so more flood risk).
How can he say the models show "sudden downpours"? The "flood risk" has always been there despite how much money being poured in over how many years?
What was that old saying..."Do not give a man a fish, give him a net and teach him to fish" and possibly a PDF on the Southern Oscillation may come in handy!
Local land-use factors are not relevant?
Frosty.
The "underlying problems" are, of course, the lack of proper infrastructure. Drought is not something we can do much to prevent (global warming or no global warming); famine certainly is. I am very cynical about the willingness of the NGOs actually to take steps to solve this problem. We are continually being asked to "firefight" by pouring money into short-term famine relief which is why I refuse to support the likes of Oxfam (see my reply to Philip on the Discussion page here - http://www.bishop-hill.net/discussion/post/1545815, not to mention this on my own blog last November - http://standstoreason.wordpress.com/2010/11/29/charity-begins/).
Perhaps if the EU were to put boots on the ground in North-East Africa instead of Iraq, Libya, and Afghanistan which, for all they may be (or have been) unpleasant regimes and potential future threats (maybe) are not actually turning their own citizens into starving refugees, we might get round to solving this problem.
But the cynic in me asks whether the NGOs really and truly want to solve the problem or whether they are misguided enough to believe that dragging these people out of abject poverty and death by starvation represents a threat to the future of mankind.
For sure there are some that do and there are names that spring fairly readily to mind.
More of the shrinking capital of goodwill for Oxfam will be spent by this article by Green. I suspect the environmentalists are now sitting on a much reduced pile of such goodwill, and that the 'developmentalists' such as Oxfam will suffer the same fate. They have all aided and abetted the political initiatives, such as the plainly lunatic Climate Change Act, that are blighting industries and landscapes, as well as physical and mental wellbeing, in so many places.
No doubt Oxfam will be again clamouring for 'climate tribunals', as it did in Bangladesh.
By the by, does anyone know what its position on GM is? While I am well aware that FOE and Greenpeace were foremost among the NGOs that have exacerbated starvation in Africa by misleading African governments over the 'risks' of GM, I'm not clear where Oxfam stands.
Once you've created a model where every change in the weather 'is consistent with' global warming, then every time there's a storm, or the lack of one, you can start bleating about global warming and point to the models as justification.
It's taking a long time to break that down, but their constant crying 'wolf' is slowly getting the derision it deserves.
'Proper' land use is in the eye of the beholder and is usually culturally defined. I know little about Africa except for generalities, but I do know that in the UK most urban dwellers are so far removed from the ramifications of weather that they cannot see the innate stupidity of covering flood plains with buildings, concrete and tar sealing. Seeking 'magic' solutions from 'climate science' when the inevitable flood seriously damages buildings and infrastructure on said flood plains ignores the mechanisms that created the nice, handy flood plains in the first place over a very long period of time.
Transport these same weather-ignorant urban dwellers to Africa where the climate and the indigenous cultural practices are utterly foreign to them and which they do not even begin to understand and the transported urban-dwellers' response of looking for answers in the wonky models of climate science is just as innappropriate and just as silly when applied to Africa as it is in the UK.
on land management and drought, the work exampled in this video of Allan Savory "argued that while livestock may be part of the problem, they can also be an important part of the solution. He has demonstrated time and again in Africa, Australia and North and South America that, properly managed, they are essential to land restoration. With the right techniques, plant growth is lusher, the water table is higher, wildlife thrives, soil carbon increases and, surprisingly, perhaps four times as many cattle can be kept."
the video examples reversing desertification, during a drought, by changing grazing management, indicating it was poor grazing management that caused desertification in the first place.
http://vimeo.com/8239427
Mike Jackson: I may be even more cynical, specially concerning our involvement in N.Africa, the "revolution" may not be all it seems.
The Revolution Business (Serbian Subtitle)
http://www.youtube.com/watch?v=os0xWtohvjo
News items you might have missed in the past week -
'Thousands of displaced Somalis fleeing drought and famine are now dealing with heavy rain and flooding which have left their make shift tents demolished.'
http://digitaljournal.com/article/309786
If Oxfam learned that some potential donors could be sceptical about their conflation of climate change and CAGW, they might be forced to reconsider. Which would be interesting...
this analysis struck me as being a fair assessment of the situation in East Africa. there are other reasons as well, e.g. some of the refugees in the main kenyan camp are Ethiopians who have fled because their villages have been burned down by their own government:
30 July: Aljazeera: Abdi Ismail Samatar: Genocidal politics and the Somali famine
The blame for Somalia's devastating famine should not be levelled at the weather, but at geopolitics and armed militia.
Abdi Ismail Samatar is a professor of geography at the University of Minnesota and a research fellow at the University of Pretoria, South Africa.
http://english.aljazeera.net/indepth/opinion/2011/07/2011726135256169831.html
AFP's Karin Zeitvogel wrote a piece on 2 Aug which had the following headlne in most countries, including France:
2 Aug: AFP: Karin Zeitvogel: Africa bank says Somalia war key to famine
http://www.modernghana.com/news/343077/1/africa-bank-says-somalia-war-key-to-famine.html
for reasons unknown, Australia's Fairfax media either changed the headline to include "climate change" or Zeitvogel (for whom alarmist articles are de rigeur) presented Fairfax (and Sky News Australia) with an inaccurate headline, as Donald Kaberuka, the head of the African Development Bank, makes no mention whatsoever of AGW aka "climate change" in the AFP text:
2 Aug: Sydney Morning Herald: AFP: Famine due to climate change: African bank
http://news.smh.com.au/breaking-news-world/famine-due-to-climate-change-african-bank-20110802-1i8nn.html
and now we have:
5 Aug: Greens MP Lee Rhiannon: Greens praise Newcastle anti-coal direct action
Federal Greens Senator for NSW Lee Rhiannon today congratulated Rising Tide activists who scaled a coal conveyor belt at the Port of Newcastle to highlight the link between coal, climate change and famine in Somalia.
“Non-violent actions are a courageous way to underline the urgent need to combat the global impacts of climate change by constraining the growth of NSW’s coal industry,” Senator Rhiannon said.
“Ship after ship leaving Newcastle Port, heaped with coal, are contributing to the greatest threat we face in human history...
http://lee-rhiannon.greensmps.org.au/content/news-story/greens-praise-newcastle-anti-coal-direct-action
so much for the scientific method.
"caused by climate change"
This struck me as peculiar as well, Jack Hughes.
Climate Change is cause and effect. It's All Things To All People At All Times. It's Everything.
Andrew
What has some of us banging our heads on the wall (or chewing the carpet, according to taste) is this deliberate and either dishonest or pig-ignorant conflation of global warming and famine.
People are dying literally in their thousands, possibly millions, and this eco-prat either doesn't understand why or, worse, he does understand why but is prepared to lie about it for his own purposes.
Words (unusually) fail me.
Mike
When it comes to Oxfam - and others - misrepresenting the effects of poverty, politics, population, over-grazing, deforestation and water resource mismanagement as those of climate change, I prefer the corner of my desk.
Famine and climate change – what’s the link?
Well the answer is none!
1. Drought in this part of Africa is closely associated with La Nina.
2. Famine is closely associated with war and political strife.
3. The IPCC AR4 projected that East Africa will see a rise in percipitation due to climate change.
4. Famine in the Horn of Africa is due to civil war (a human factor) and La Nina (a natural factor).
5. Climate change has sod-all to do with famine in this part of Africa.
6. Oxfam should sack their head of their research, Duncan Green, because his analysis has brought the NGO into disrepute.
Among many other papers about this subject, there is new paper in Science this week demonstrating that East Africa and the Horn of Africa rainfall is very strongly correlated to the ENSO and to general temperature conditions.
During La Ninas, there is less rainfall and drought. During El Ninos, there is substantially more rain.
In warmer climate conditions, like the Medieval Warm Period, there is more rain. When the climate is cooler, as in the Little Ice Age and Ice Ages, there is less rainfall. So we have an ENSO signal superimposed on the general climate conditions.
This was already generally well-known and is portayed in ENSO climate impact maps for example. In addition, during the Holocene Optimum, the Horn of Africa and the Sahara was more like savana as it received more rainfall.
http://www.sciencemag.org/content/333/6043/743.abstract
BBD
With salt and pepper or mustard?
Latimer
I am extremely cautious about what can sensibly be said about the impacts of future climate change on agricultural productivity - here is a paper by my team on the subject.
I'd be even more cautious about attribution statements concerning specific events now or in the recent past. The signal to noise ratio for precip is, as you know, extremely high. It might be possible to do something on "fraction of attributable risk" ie: using climate models to run multiple versions of recent climate with all current forcings and then multiple versions of "the world that might have been" (ie: without anthropogenic forcings) to see if the likelihood of a particular event has changed - assuming of course that the models are a reasonable guide to this. I don't think anyone has done that yet for the current event in East Africa, and even if they had it would require a lot of looking at to see if it was saying anything sensible.
I agree with mondo that local land use effects should be considered. There are good reasons to think that anthropogenic land cover change may play a role in regional climate change, and in the tropics, reduced vegetation cover seems to lead to reduced precip. See this submitted paper by Roger Pielke Snr and others, including myself and Andy Pitman (another IPCC AR4 author) - in particular, note the discussion on the famous "Bunny Fence Experiment" in W. Australia.
So overall I personally think the climatic causes of the current E African famine are very much an open question.
95% of East Africa's forests have been destroyed in the last 60 years by a rapidly increasing local population so it would be surprising if this did not impact on the regional climate. Nothing to do with carbon emissions however.
Richard Betts -
Dr Pielke Sr wrote recentlythat "there has been NO demonstrated multi-decadal climate regional predictive skill."
Perhaps the real state of affairs is more nuanced than that. Can you expand upon the degree to which regional effects can be reliably predicted?
Bishop
Chris Funk et. al. recently pointed out in Nature that the IPCC global climate models have it all wrong. using the global models, in 2007 the IPCC forecast [I know they say they don't forecast, but they do..] that AGW/ACC would cause the Horn of Africa to become WETTER, not dry out as it has.
As Pielke Sr and others [including Trenberth] have pointed out repeatedly, GCMs are useless, and we need to focus on regional data and models if we are to understand anything.
Meanwhile energy and agricultural policies continue to be based on fundamentally flawed 'science".
Your conclusion that drought is not an issue we should worry about is based on the same uncertainties (and imprecisions) in the projections you claim are being skirted over.
An interesting article from Nature.com "The global climate models used by the Intergovernmental Panel on Climate Change were never intended to provide rainfall trend projections for every region". It suggests the problem of famine is largely political.
The same uneducated argument was recently made by Herve Le Treut, academician, IPCC author, Director of the LMD, pillar of pseudo climatology at the IPSL...
Here is a report showing the droughts in Africa were predicted in as early as 2008
http://nzclimatescience.net/index.php?option=com_content&task=view&id=767&Itemid=1
Of course if this drought and famine was not caused by climate change, this would be consistent with the Ethiopian drought and famine in the early 80's. Politics and civil war, man made, yes. Not so much climate change as history repeatng itself
Mike
Re desk corner chewing, you ask:
Usually just bile, but I'll take cracked pepper and lemon juice, or even horseradish sauce if they are to hand.
Hengist
the problems of famine are largely political. Drought is a fact of nature. It rains or it does not. Still, the impacts can be altered by Governments building reservoirs, water-transport systems. Do you ever think before you post or do you just accept unreasoningly the pronouncements of whatever soundpiece is plugged in your ear?
Hengist , was the UK drought of 1976 due to global warming?
HaroldW
Predictions of regional climate change should definitely be treated with caution, and while there is greater confidence in some parts of the world (eg: the Mediterranean) than others (eg: the Amazon) due to the specific physical mechanisms involved, I share Roger’s concern that there is a significant degree of over-confidence in these projections (usually by third parties rather than the modellers themselves, although the latter clearly have a responsibility to make the limitations clear to the former).
It actually worries me quite a lot that the IPCC AR4 multi-model ensemble (and regional models projections nested within this) are becoming regarded in some quarters as some kind of authoritative statement on what the future really holds for specific regions. Generally speaking, my view is that the projections should only be regarded as physically plausible scenarios of what may happen - not what will happen.
Tetris
While the AR4 projections were indeed for an increase in annual mean rainfall in East Africa, this was for average changes in the longer term (several decades away) not the next few years after 2007. If what is happening now is merely natural variability then this would not be inconsistent with a longer-term trend toward wetting – you are bound to get both wetter and drier episodes around any kind of trend. The AR4 models were not designed to make near-term forecasts. Basically it is too early to say whether the models are either right or wrong.
Incidentally, Roger specifically does not say that regional models are preferable to global models – indeed he correctly points out that RCMs are limited by the boundary conditions provided by the GCMs. If the projections of the latter are rubbish, then all you get from the RCM is high-resolution rubbish! It is a common misconception that RCMs are somehow better simply because they are higher resolution, but this is not correct – they only give you a higher-resolution interpretation of what the GCM is doing.
I’m not saying that either RCMs or GCMs are worthless – they can be informative if interpreted appropriately. But there is still a long way to go before they can be relied upon for actual forecasts at the regional scale.
I agree with Hengist that it is wrong to conclude that we should not worry about drought. While the models (and physical reasoning) suggest that global average precipitation should increase in a warming world, this doesn't imply an increase in rainfall everywhere. Differential patterns of warming around the world can be expected to alter atmospheric circulation and hence rainfall patterns such that some places get wetter and others get drier. The challenge is knowing which will happen where! Just because we can't predict the regional detail doesn't mean it's not an issue. Of course to some extent this could, in theory, be dealt with through adaptation (possibly with limits) - but one thing the current situation in East Africa shows us is that this is not always possible in practice due to other (non-climatic) constraints.
Dr Betts --
Thanks for your elucidation of the merits and limitations of such forecasts.
Perusing the various climate-related websites, I often feel as if in a classroom. The great advantage over merely reading papers and postings, is the ability to ask questions. Thank you for providing your tuition here; it is greatly appreciated even if not always acknowledged.
It's a disgrace.
Oxfam is one of the aid-organisations to blame for these tragedies.
And now again they will only feed them but not help them.
I wonder if Duncan Green ever thinks of that when he gets his pay.
http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/books/book_extracts/article7107052.ece
Richard
Re your point about over-confidence in the IPCC model ensembles - I think there is a problem with the use of the word "expected", which implies a high degree of confidence. "Plausible" is a better term IMHO.
Richard again
Re worrying about drought. I am in broad agreement with your assessment of the question - to paraphrase, we know nothing about whether any particular region will get wetter or dryer, but overall we expect (I think we are pretty confident of this, assuming warming) wetter. In those circumstances I would have thought we can find other things to worry about.
Hi Richard
Thanks for your replies to me and to others, It is always good to hear the views of the practitioners directly rather than through the interpretations of third parties.
I found two things particularly interesting.
1. In your referenced paper, you and your team conclude
'...even the sign of crop yield projections is uncertain' and
'Overall, it does not appear to be possible at the present time to provide a robust assessment of the impacts of anthropogenic climate change on global-scale agricultural productivity'
Which I take to mean that we do not (yet/ever?) know whether climate changes will be a Good Thing (= more grub) or a Bad Thing (=less grub). And not knowing this severely weakens the case for drastic action on CC issues.
2. You also state that
'there is a significant degree of over-confidence in these projections (usually by third parties rather than the modellers themselves, although the latter clearly have a responsibility to make the limitations clear to the former)'
which also seems to make a lot of sense to me.
But I don't see your remarks to this effect in the Comments section of the Oxfam article that began this discussion? Though Green ducks and dives his way through the discussion about models, it would be good to see your expert remarks added there so that nobody runs away with the idea that modles should be taken more seriously than they deserve.
And while I agree entirely with your personal sentiment of your modelling colleagues responsibilities to make these limitations clear, I see almost no evidence of them ever publicly discharging those duties.
In general the blogs are not full of modellers asserting that their work has been oversold. Indeed one (in)famous blog run by a high profile modeller is noted for its lack of introspection or doubt. The letters page of the Telegraph or Grauniad are not swamped with climatologists urging the activists not to build policy castles on soft foundations.
So please continue to tell it like it is...and to urge your colleagues to clarify the weight (or lack of) to be put on their results. Passively allowing your work to be hijacked as an excuse for any agenda does you no long-term favours. I know that you personally understand this, but your colleagues need to address it with more vim and vigour.
@Latimer Alder
Hear, hear.
BH
I agree on "expected". I try to only use that word when I consider it to appropriately reflect the level of confidence, but in the end it will rely to a certain extent on opinion (and you and I, and indeed others, may differ!)
On "we" "worrying" about drought - I guess it depends on who "we" means, and what we are worrying "for".
If it's about the need to consider GHG emissions cuts, then drought is merely one of several reasons for concern in the long term, and I agree with you (and Latimer) that it is probably less of a compelling issue than others (like sea level rise, river flooding, or biodiversity loss).
But if it's about adapting to climate change and variability (from whatever cause), and you live in a marginal area (or are involved in development or humanitarian assistance in such areas) then drought risk may be of huge concern. This morning one of our partners from the Regional Climate Outlook Forum in East Africa was telling us about the process they have in place for responding to seasonal drought forecasts (the situation would have been even worse if this was not in place), and there are issues requiring longer-term planning too - eg: the majority of energy in Kenya comes from hydroelectric, and they are currently in trouble because of lack of water - hence when further developing their energy infrastructure they need to think about how to make it resilient.
So when I talk about "worrying" about climate issues, my interest goes beyond the mitigation agenda. Adaptation is critical (hence the need to keep trying to improve the models' forecast skill, especially on seasonal to decadal timescales!)
BTW Latimer: I'd not seen the original Oxfam article. I will continue to encourage more of my colleagues to engage directly :-)
Latimer
I've sent a post to Duncan Green. Having now read his article I think he did make it fairly clear that the models gave no clear signal - maybe it was the fact that he cited the "drying" projections after the "wetting" ones that caused the concern here?
@Richard Betts
Thanks again. I think that interactions like this serve to illustrate the great value of fora where civilised discussion between people of different views is possible and encouraged.
I'm sure our host would agree that the more you can persuade your colleagues to contribute here and elsewhere the better.
The drought is climate related though not necessarily 'climate change ' related.
The famine is politically related.
Duncan's article contains less substance and more evasions and banalities than a Barack Obama speech.
Hi Latimer
I've tweeted a call for other climate scientists consider joining the discussion here.
I'm no climate scientist (or any other kind), and imo,
In a land where floods are possible, droughts are caused by lack of water storage capacity - and so are floods.