I wish it would rain

by Bryan Walker on November 28, 2010

We (or at least some of us) rightly feel apprehension and alarm at the prospect of melting glacial and polar ice. There are new reminders that we should be equally alarmed at the prospect of Amazonian drought. Joe Romm has written a lengthy post on Climate Progress drawing attention to the 2010 drought which may prove more widespread and severe than the 2005 drought, itself identified as a 1-in-100-year type event.  He quotes an email to that effect from forest scientist and Amazon expert Simon Lewis (he of the Sunday Times fightback and subsequently granted apology).

Lewis recommends an article in the Global Post which is well worth reading.  It refers to three scientists. Oliver Phillips, a tropical ecology professor at the University of Leeds, speaks of his concern that parts of the Amazon may be approaching a threshold point beyond which the eco-system can’t go. He led a team of researchers who studied the damage caused by the 2005 drought which caused a massive die-off of trees and led to the forest expelling carbon dioxide rather than absorbing it. He’s worried that another severe drought is following so soon after the last one.  Greg Asner, an ecologist at the Carnegie Institution for Science, points out that some tropical forests in the world now are starting to be exposed to temperatures they’ve never experienced. His studies show that higher temperatures and shifts in rainfall could leave as much as 37 percent of the Amazon so radically altered that the plants and animals living there now would be forced to adapt, move or die. Foster Brown, an environmental scientist at the federal university in the Brazilian state of Acre, comments that drought has made ecosystems so dry that instead of a being a barrier to fire, the forest became kindling.

Nikolas Kozloff’s book No Rain in the Amazon which I reviewed earlier this year refers to much-cited scientist Philip Fearnside of Brazil’s National Institute for Research in the Amazon, who for some years has observed the connection between drought and El Niño-like conditions which are expected to become more frequent with continued global warming. He too is concerned that the Amazon might dry out and be placed in jeopardy as a result of climate change. Kozloff also reports the belief of some researchers that warming sea surface temperatures in the tropical North Atlantic Ocean are linked to Amazon drought.

In an October press release Brazil’s Amazon Environmental Research Institute (IPAM) comments:

“The drought of 2010 still hasn’t ended in the Amazon and could surpass that of 2005 as the region’s worst during the past four decades… Even if this doesn’t occur, the forest will have already experienced three extreme dry spells in just 12 years, two of which occurred during the past five years: 1998, 2005 and 2010. And this is not including the drought of 2007, which affected only the Southeastern Amazon and left 10 thousand sq. km. of forest scorched in the region…`The Amazon that had wet seasons so well-defined that you could set your calendar to them – that Amazon is gone,’ says ecologist Daniel Nepstad of IPAM…”

Deforestation of the Amazon by humans has long been a major international concern, and Simon Lewis’s communication with Jo Romm indicates that there is a degree of good news on that front in that since 2005 deforestation rates have been radically reduced. But the droughts are bad news. They kill trees and promote damaging fires, “potentially leading to a drought-fire-carbon emissions feedback and widespread forest collapse”. Lewis expresses particular concern that while two unusual droughts clearly don’t make a trend, they are consistent with some model projections made well before 2005: “that higher sea surface temperatures increase drought frequency and intensity, leading later this century to substantial Amazon forest die-back.”

Hot Topic commenter Tony on a previous post linked to an Al Jazeera video clip (which I’ve posted below), with the observation that if anything should motivate a sense of urgency in Cancun, what it portrayed should. Simon Lewis also linked what may be happening in the Amazon to the Cancun conference. Not with any great expectation, but with a dry reminder that the risks to which we are exposing humanity don’t diminish because we ignore them. “While little is expected of the climate change talks in Cancun next week, the stakes, in terms of the fate of the Amazon are much higher than they were a year ago in Copenhagen.”

I hope it doesn’t appear as incidental if I note before concluding that the droughts affect not only the forest and through it the welfare of the whole planet but also the local populations whose livelihood and wellbeing is jeopardised. The Global Post article reports the anxiety of village chief Mariazinha Yawanawa. Her people are sustained by the forest. They hunt in the woods, fish the rivers and grow crops in the clearings where they live.  “Everything has changed. We don’t know when we can plant. We plant and then the sun kills everything. If it continues like this, we expect a tragedy

[The Temptations]

{ 41 comments… read them below or add one }

Dappledwater November 29, 2010 at 8:11 am

His studies show that higher temperatures and shifts in rainfall could leave as much as 37 percent of the Amazon so radically altered that the plants and animals living there now would be forced to adapt, move or die

Moving won’t be an option for many. The rainforest is constrained by the frost-free zone. The large equator to pole temperature gradient which now exists, and is expected to do so for the remainder of this century, plus encroaching farmland, means the rainforest is going to be “squeezed”. Sadly, dying seems the most likely scenario.

They kill trees and promote damaging fires

This is perhaps one of the the most damaging positive feedbacks of drought in the Amazon. Because fire is historically such a rare natural occurrence in the rainforest, trees there have not developed any adaptive mechanisms to deal with it. Even piddly little low level primary fires (flames reaching about only 200mm in height) kill over 40% of trees, because they typically have very thin bark. Drying of the leaf litter and falling branch debri provide kindling for subsequent fires and cause more intense fires. Secondary fires kill over 95% of trees.

“If” the Amazon rainforest undergoes die-back we are likely to see an extra 16 to 36ppm jump in the levels of atmospheric carbon dioxide, and a major change to the world’s hydrological circulation.

Great piece by the way Bryan. Any plans on covering the vast coral bleaching which has occurred this year?. Skeptics might delude themselves that the Earth isn’t warming, but out in the real world there are worrying signs that natural systems are undergoing profound change that will have consequences for life on Earth.

Bryan Walker November 29, 2010 at 9:21 am

I’ll see how I go on putting something together on this year’s coral bleaching Dappledwater. I retain a strong memory of the sombre concerns expressed by John Veron in a lecture on which I posted last year. The scope of climate change effects is certainly telling, and alarming. While I was writing the above post I found myself reflecting on the massive ignorance of the politicians in the US (and elsewhere no doubt) who seem to have no idea of the range of the science which in so many different aspects of Earth’s life is bearing news of disruption and danger.

cynicus November 29, 2010 at 10:57 am

Thanks for the pointer to Veron’s talk at the RS, Bryan. I had a little difficulty locating the talk and other people might want to watch it too (highly recommended), so here’s the link (search for “barrier reef” to find the presentation): http://royalsociety.org/All-our-Web-casts/

What a thoroughly depressing message…

Thomas November 29, 2010 at 11:04 am

Another interesting paper is this here by NASA on the warming of major lakes. Lakes are a useful GW thermometer with a particularly useful combination of thermal latency and responsiveness.


“They reported an average warming rate of 0.45 degrees Celsius (0.81 degrees Fahrenheit) per decade, with some lakes warming as much as 1 degree Celsius (1.8 degrees Fahrenheit) per decade. The warming trend was global, and the greatest increases were in the mid- to high-latitudes of the Northern Hemisphere. ”

Note the speed of up to 1 Deg/decade!!!

Tony November 29, 2010 at 11:54 am

Reading about the Amazon reminds me of this famous quote from the movie Planet of the Apes (1968).

“[reading from the sacred scrolls of the apes] Beware the beast Man, for he is the Devil’s pawn. Alone among God’s primates, he kills for sport or lust or greed. Yea, he will murder his brother to possess his brother’s land. Let him not breed in great numbers, for he will make a desert of his home and yours. Shun him; drive him back into his jungle lair, for he is the harbinger of death.”

Perhaps the denialists can explain to us how all the extra CO2 fertiliser will help boost productivity in the Amazonian die-back.

MrSmith December 2, 2010 at 7:19 pm

I sometimes wonder if climate change is evolutions way of keeping in check the Human race.

Artful Dodger November 29, 2010 at 1:25 pm

I wish we would stop clear cutting our heritage. And not just in the Amazon.

R2D2 November 30, 2010 at 9:43 am

So Britain has been hit with a cold snap while the early signs are NZ seems set to have a warm dry summer. The debates on weather vs climate set to begin again????

laurence November 30, 2010 at 1:51 pm

Since you are the genius who knows all about it why don’t you explain it all to us mere mortals. While you’re at it tell us why we should listen to you and not the people that actually put in the hard yards. Give it your best shot, see if you can surprise us.

R2D2 November 30, 2010 at 3:26 pm

It’s very difficult to tell. We may yet have a wet summer. That is the norm for La Nina. But it has started dry, and the last major drought in 2007-08 was a La Nina. That was a hundred year drought so to have another anywhere near as bad would seem extraordinary. Hopefully the highs blocking the tropical lows move soon and we get rain. But we will have to wait and see. Climate change or just weather? I don’t know. But I would say/guess we have to wait to find out – not enough data.

I think the cold spells in the UK are caused by changes to the jet stream and my understanding is they are not CO2 related. But I’m not an expert. I’m interested in other people’s opinions and expertise.

Carol Cowan November 30, 2010 at 9:40 pm

What is causing changes to the jet stream, R2D2?

R2D2 December 1, 2010 at 12:33 pm
Macro December 1, 2010 at 4:38 pm

I couldn’t read anywhere that this was linked to Solar Activity R2?
Actually I followed the link but as it is only a “teaser” and does not give the full article I can’t fully say – If N S suggests somewhere later in the article that it may be changes in solar activity I would say that that was drawing a pretty long bow! No one else seems to be drawing those conclusions as to the root cause for such an extreme event.
Yes I went further and had a look elsewhere – almost same article – certainly same words – and a full article to boot. In the later part of the article I read I found this:
“Blocking events are not the preserve of Europe and Asia. Back in June, a similar pattern developed over the US, allowing a high-pressure system to sit over the eastern seaboard and push up the mercury. Meanwhile, the Midwest was bombarded by air from the north, with chilly effects. Instead of moving on in a matter of days, “the pattern persisted for more than a week”, says Deke Arndt of the US National Climatic Data Center in North Carolina.
So what is the root cause of all of this? Meteorologists are unsure. Climate change models predict that rising greenhouse gas concentrations in the atmosphere will drive up the number of extreme heat events. Whether this is because greenhouse gas concentrations are linked to blocking events or because of some other mechanism entirely is impossible to say. Gerald Meehl of the National Center for Atmospheric Research in Boulder, Colorado – who has done much of this modelling himself – points out that the resolution in climate models is too low to reproduce atmospheric patterns like blocking events. So they cannot say anything about whether or not their frequency will change.”

R2D2 December 1, 2010 at 8:56 pm

The last 2 paras:

“There is some tentative evidence that the sun may be involved. Earlier this year astrophysicist Mike Lockwood of the University of Reading, UK, showed that winter blocking events were more likely to happen over Europe when solar activity is low – triggering freezing winters (New Scientist, 17 April, p 6).

Now he says he has evidence from 350 years of historical records to show that low solar activity is also associated with summer blocking events (Environmental Research Letters, in press). “There’s enough evidence to suspect that the jet stream behaviour is being modulated by the sun,” he says.

Blackburn says that blocking events have been unusually common over the last three years, for instance, causing severe floods in the UK and heatwaves in eastern Europe in 2007. Solar activity has been low throughout.”

There are plenty of links here:


Sorry, my answer to Carol’s question should have been, “it is not known for sure”. But I took the bait. I think there is a little evidence for solar activity and no evidence that AGW is causing the blocking events. It could be random weather. It could be something people haven’t thought of.

CTG December 2, 2010 at 7:49 am

Anything But Carbon. Just keep repeating it to yourself, R2, Anything But Carbon.

Say it often enough and it becomes true. Voila, problem solved – no more global warming. Anything But Carbon.

Macro December 2, 2010 at 10:35 am

hmmm Interesting R2..
So you are happy to take “tentative evidence” regarding blocking events as a fact.
But you seem very reluctant to accept the huge mountain of evidence (which grows daily) concerning anthropogenic global warming.

R2D2 December 2, 2010 at 11:42 am

“So you are happy to take “tentative evidence” regarding blocking events as a fact.”

That’s a little unfair Macro.

My quotes, (emphasis added)

“New Scientist suggested it could be solar activity”

“I think there is a little evidence for solar activity and no evidence that AGW is causing the blocking events. It could be random weather. It could be something people haven’t thought of.”

I’m happy to take the evidence as fact. The only conclusion that can be yet drawn from that evidence is that solar activity could have a link to these events, and further investigation is warranted to better understand them.

I also suggest that if a theory, in this case AGW, predicts one trend (more extreme weather), it is not OK to then conclude that any increase in that trend must be caused by that theory without investigating the trend fully. Especially when the subject being investigated (weather) is subject to randomness anyway.

“But you seem very reluctant to accept the huge mountain of evidence (which grows daily) concerning anthropogenic global warming.”

I am not sure what you expect me to do. I accept CO2, CH4 and N20 are greenhouse gases. I accept that increasing them should lead to increased radiative forcing, ceteris paribus. I even accept that the developed world should aim to reduce the use of fossil fuels. I do not accept uncritical conclusions linking every catastrophe to “global warming”. I do not accept emotive debate. I do not accept broad sweeping all conclusive statements on subjects we know little about.

Macro December 2, 2010 at 12:54 pm

“I think the cold spells in the UK are caused by changes to the jet stream and my understanding is they are not CO2 related. But I’m not an expert. I’m interested in other people’s opinions and expertise.”
Perfectly fair!
You are happy to shift any climatic extreme to a blocking of a jet stream – thereby shifting the cause from FF to which you are heavily addicted.

R2D2 December 2, 2010 at 3:56 pm

Well the changes to the jet stream were observed!


The only ‘debate’ is about the influence AGW may have on the jet stream vs natural blocking events. The heat wave wasn’t caused by the world climate suddenly rising 10C Macro, an issolated event of some kind has occured.

Macro December 2, 2010 at 8:13 pm

“The only ‘debate’ is about the influence AGW may have on the jet stream vs natural blocking events. The heat wave wasn’t caused by the world climate suddenly rising 10C Macro, an issolated event of some kind has occured.”
Sorry but I don’t think it’s as black or white as that. There is a tentative suggestion that low solar activity my have some influence on blocking events,
“Professor Hoskins does not expect a drastic change in the way blocking events happen, though their locations may alter a bit. The climate-change message from what is going on this summer, he says, is not to do with the blocking itself, but its consequences. In a cooler world, this sort of high pressure over Russia would be less likely to result in such a dramatic heatwave; nor, probably, would the floods in Pakistan have been so bad.”

R2D2 December 2, 2010 at 9:21 pm

Macro, to me that quote says that the event was caused by a natural event but was made worse by climate change. That seems perfectly reasonable. But that is a very different statement to saying the event was caused by climate change. And that is the message that is being put out by some quarters (Oxfam).

CTG December 3, 2010 at 8:01 am

R2, you are the one who keeps saying “caused by”, and trying to split things into “natural” and “man-made”. If you would just take the time to read some of the scientific literature, you would not see anyone claiming that AGW “causes” any particular weather event. The earth’s atmosphere is a complex system, with multiple factors involved in the evolution of all weather systems.

Now, there is certainly plenty of evidence that the high SSTs in the Arctic Ocean play a part in these blocking events, but you completely ignore that, for some reason. Could it be because a rapidly warming Arctic is one of the signatures of CO2-forced warming?

In any case, it is unlikely that it is going to come down to solar activity or Arctic warming that is “the cause” of blocking events. It is highly likely that both of these, and probably other factors as well, are involved.

The simple fact that you are desperately ignoring is that the earth’s atmosphere is in a different state today than it would have been if we hadn’t pumped billions of tons of CO2 into it. This extra CO2 means that there is a systematic influence on the earth’s weather systems that is due to human activity.

So please, please, stop all this unscientific nonsense about whether this or that “caused” a weather event.

Le Chat Noir December 2, 2010 at 11:04 am
Mark December 1, 2010 at 10:12 am

“Hot debate. What do you think?”

We have seasonal fluctuations that are partly related to the chaos of individual weather events, partly to larger-scale modes of atmosphere-ocean variability (ENSO, NAO) that may well affected by anthropogenic forcing, but generate intrinsic variability of their own, against a background of an Earth that is warming, more in some areas than others, very likely due to anthropogenic forcing. What sort of hot debate are you envisaging?

R2D2 December 1, 2010 at 12:32 pm

I was imagining a more ludicrous one, like these threads:


Your comment is spot on. I guess by prompting it I have successfully directed the debate back to the middle ground?

bill December 1, 2010 at 9:50 pm

Interesting – that first link goes to a virtuoso display of trolling from Wrathall and someone running the ‘Rachel Carson has killed millions’ meme – is this the ludicrous behaviour you’re referring to?

Carol Cowan December 1, 2010 at 8:32 pm

“Hot debate. What do you think?
The comment above is software-generated, not typed by the person writing the post. Just to clarify for you.

Mark December 2, 2010 at 8:14 am

Oh I see. That’s the system that hides the posts that people dislike? And it adds silly captions too? Whoopee.

Gary Young November 30, 2010 at 6:26 pm

So R2D2

‘It’s very difficult to tell’, ‘we will have to wait and see’, ‘I don’t know’.
‘not enough data’, ‘But I’m not an expert’.

Um…so what exactly was the point of your initial comment?

R2D2 December 1, 2010 at 12:16 pm

My point was to front foot the kind of comment made by ‘Joe Fone’ on the Cancun thread. I am not going to say that cold weather is proof AGW doesn’t exist. I am equally not going to say a dry summer is evidence that it does. I assume some at either end of the spectrum (but that are not actually that different) will try to argue this.

Carol Cowan December 2, 2010 at 11:03 pm

R2D2, I am tending to agree with you, especially that global warming is intensifying some natural events. I am not sure why you are getting so many “dislike” ticks on your last few comments – they have seemed reasonable to me.

Le Chat Noir December 3, 2010 at 11:35 am

This is Galactica Actual:

Monsieur RD’s principal contribution here is to harass, disrupt, impede or prevent the positive forward flow of any discussion. He should change his handle to Y2≠2.

When others are diligently searching for the 13th Colony, constant “why-notism” only hinders progress. Cylons (and other artificial or phoney life forms including members of the genus Trollius) should not be surprised when any contribution, however reasonable, is greeted with a collective “frack you”.

Carol Cowan December 3, 2010 at 1:05 pm

Oh well, I was just noticing he wasn’t being as troll-like as some other visitors here. I am teacher aide to a ‘special needs’ kid – I tend to hand out stickers for better-than-usual behaviour.

bill December 3, 2010 at 2:19 pm

Actually, I thought it was rather apt when he was still called C3PO!

I agree that R2 is broadly a member of the Concern Troll (Trollus concernus) species, in his case he’s rather marked out his own territory as sub-species lucius – always just about to be convinced by some overwhelming piece of evidence but can never quite manage it, always claiming not to deny AGW but never accepting any piece of evidence for it, just as Lucy invariably pulls the football* away from Charlie Brown just as he’s about to kick it, though Charlie is always oddly compelled to go through the ritual! Just as some will always feel they have to respond…

However, unlike some of our ‘regulars’ who really merit the name ‘Troll’ he’s not routinely abusive – in my view they forfeited any right to participate some time ago – and he manages to stick to the topic about as often as the rest of us do.

Arguments that amount to ‘yes, but there is some doubt’ become rather wearing, but may be useful in honing counter-arguments.

*why to the Americans call it a football?

RW December 3, 2010 at 4:09 pm

Well put Bill. My take is that R2D2 is simply being more cunning and therefore more polite – rather than being a more obviously obnoxious cherry-picking automatic-gainsaying denier in the Joe Fone, Wrathall, Dewhurst, Lank, …. mould. But I think the objective is just the same – to distract, delay and disrupt.

adelady December 4, 2010 at 3:18 pm

why do the Americans call it a football?
Same reason as rugby I suppose. Because they sometimes kick the ball.

In my view the only real *foot*ball games are those where one is *not* allowed to run with the ball in hand – soccer, AFL, Irish football.

adelady December 4, 2010 at 3:25 pm

Distract, delay and disrupt? I’m not so sure. At least for the person you’re referring to.

Defend might be better. That is, defending your own belief, approach, sanity from intrusions that would upset the balance you currently have. You know, smiling desperately at the bank manager while discussing your not-so-wonderful financial position.

The rest of them? A pox on all their houses.

Macro December 4, 2010 at 3:47 pm

Rationalisation it’s called.
rationalisation – (psychiatry) a defense mechanism by which your true motivation is concealed by explaining your actions and feelings in a way that is not threatening
The addict says – “I can handle this – I can give it up any time I want”.
To be committed to consumerism and “growth” is much the same. Those who can see no other way of life could never conceive that in fact western lifestyles could be much improved by abandoning the relentless pursuit of growth above all else. To be faced with the stark reality that western lifestyles based on a consumer economy is killing the planet is something those of a more neo-liberal bent do not wish to face up to. It was market economies that got us here – and this is pretty good! So why give it up?

Le Chat Noir December 4, 2010 at 7:18 pm

Adelady, maybe a few quotes will help to convince you? No prizes for guessing the source….

But my main premise is that anthropogenic global warming is an unproven, and unquantified theory, and nothing you have said changes my opinion on that.

So not only is AGW unproven and unquantified, its based on loose science.

How mush of an affect on climate is the pacific decadal oscillation going to have? How much of an affect is the current solar minimum going to have? Are the current temperature readings right? Or do satellites disagree with them?

Sorry but I will listen to pro AGW arguments for a time, but once they start claiming the hockey stick graph ‘has stood up to scrutiny’ they lose all creditability

Yeah we we we, you and all the great meteorologists while people like William Kininmonth are just cranks.

Bryan Walker December 4, 2010 at 7:46 am

Jeff Masters’ Wunderblog has an interesting post on the Amazon today, announcing the return of rain after the months of drought, and also including observations on the part the warmer Atlantic waters may have played in the drought and more generally on the importance of the Amazon for earth’s climate. Well worth a look.

Dappledwater December 4, 2010 at 10:43 am

announcing the return of rain after the months of drought

About time. The Amazon wet season occurs during the Southern Hemisphere summer (it’s a tad more complex than that, but that’s the general picture for much of the Amazon), so that’s a relief.

La Nina over the wet season historically means more rain than normal. Hopefully this will re-charge soil moisture in the region and help trees survive the next drought.

As for warming tropical Atlantic waters, both coral bleaching and Amazonian drought will both be prominent features as sea surface temperatures continue to warm, and may even worsen as aerosol pollution in the Northern Hemisphere decreases:

Increasing risk of Amazonian drought due to decreasing aerosol pollution

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