Yes, Climate Change Is Worsening U.S. Drought — NOAA Report Needlessly Confuses The Issue

NOAA has issued a report on a small part of the recent brutal droughts that have hit the United States over the past few years. The report — “An Interpretation of the Origins of the 2012 Central Great Plains Drought” — is needlessly confusing, scientifically problematic, and already leading to misleading headlines.

Dr. Kevin Trenberth, former head of the Climate Analysis Section at the National Center for Atmospheric Research, has sent to reporters a Commentary on the report, which I repost below. He concludes:

This report has some useful material in it describing aspects of the drought in 2012 in the central US. But it is quite incomplete in many respects, and it asks the wrong questions.  Then it does not provide very useful answers to the questions that are asked.

Indeed, it seems odd to do a 44-page report on the drought in the Central Great Plains (in the spring and summer of 2012) when so much of the Great Plains — and Southwest — have also been in a brutal extended drought that continues to this day.

As InsideClimate News reported two weeks ago:

Drought conditions in more than half of the United States have slipped into a pattern that climatologists say is uncomfortably similar to the most severe droughts in recent U.S. history, including the 1930s Dust Bowl and the widespread 1950s drought.

The 2013 drought season is already off to a worse start than in 2012 or 2011….

A variety of leading experts explained how human-caused warming worsened the 2011 drought (see Warming-Enhanced Texas Drought Is Once in “500 or 1,000 Years … Basically Off the Charts,” Says State Climatologist). And numerous scientific studies have projected that global warming will dry out the Southwest and at least parts of the Central Great Plains:

Amazingly, in the AP story, “Federal report says don’t blame global warming for freak of nature 2012 US drought,” the lead author, NOAA’s Martin Hoerling, dismisses any possible role of Arctic ice loss in the drought:

Researchers focused on six states — Wyoming, Kansas, Nebraska, Colorado, Missouri and Iowa — but the drought spread much farther and eventually included nearly two-thirds of the Lower 48 states. For the six states, the drought was the worst four-month period for lack of rainfall since records started being kept in 1895, Hoerling said.

He said the jet stream that draws moisture north from the Gulf was stuck unusually north in Canada.

Other scientists have linked recent changes in the jet stream to shrinking Arctic sea ice, but Hoerling and study co-author Richard Seager of Columbia University said those global warming connections are not valid.

Hoerling used computer simulations to see if he could replicate the drought using man-made global warming conditions. He couldn’t. So that means it was a random event, he said.

Yet, a 2012 Geophysical Research Letters study, “Evidence linking Arctic amplification to extreme weather in mid-latitudes,” found that the loss of Arctic ice favors “extreme weather events that result from prolonged conditions, such as drought, flooding, cold spells, and heat waves.” Indeed, as Climate Central explained in April 2012:

One does not have to look hard to find an example of an extreme event that resulted from a huge, slow-moving swing in the jet stream. It was a stuck or “blocking weather pattern” – with a massive dome of high pressure parked across the eastern U.S. for more than a week – that led to the remarkable March heat wave that sent temperatures in the Midwest and Northeast soaring into the 80s. In some locations, temperatures spiked to more than 40 degrees above average for that time of year.

The strong area of high pressure shunted the jet stream far north into Canada. At one point during the heat wave, a jetliner flying at 30,000 feet could’ve hitched a ride on the jet stream from Texas straight north to Hudson Bay, Canada. In the U.S., more than 14,000 warm-weather records (record-warm daytime highs and record-warm overnight lows) were set or tied during the month of March, compared to about 700 cold records.

According to the study, Arctic climate change may increase the odds that such high-impact, blocking weather patterns will occur. The study cites examples of other patterns that led to extreme events that also may bear Arctic fingerprints, including the 2011 Texas drought and heat wave….

In fact, in October 2012, NOAA scientists themselves led research that found Arctic ice loss was driving a shift in Arctic summer winds that in turn “could also bring about shifts in North American and European weather,” as NOAA’s own release pointed out.

Indeed, the NOAA release explained:

The effects of Arctic amplification will increase as more summer ice retreats over coming decades. Enhanced warming of the Arctic affects the jet stream by slowing its west-to-east winds and by promoting larger north-south meanders in the flow. Predicting those meanders and where the weather associated with them will be located in any given year, however, remains a challenge.

The researchers say that with more solar energy going into the Arctic Ocean because of lost ice, there is reason to expect more extreme weather events, such as heavy snowfall, heat waves, and flooding in North America and Europe but these will vary in location, intensity, and timescales.

The point is that just because Hoerling couldn’t replicate the drought with his computer simulations doesn’t mean climate change had nothing to do with the 2012 Central Great Plains Drought — let alone the entire 2012 drought and the current 2013 drought.

As I’ll discuss in a future post, other models have predicted that Arctic ice loss will drive drought in the U.S. Southwest and adjacent areas.

Finally, Dr. Kevin Trenberth argues in an extended analysis that in fact Hoerling’s analysis is seriously flawed:

This report has some useful material in it describing aspects of the drought in 2012 in the central US. But it is quite incomplete in many respects, and it asks the wrong questions. Then it does not provide very useful answers to the questions that are asked.

It fails completely to say anything about the observed soil moisture conditions, snow cover, and snow pack during the winter prior to the event in spite of the fact that snow pack was at record low levels in the winter and spring. Soil moisture is touched upon in Fig. 8 from a model but not validated with any data or indices of vegetation health such as NDVI. In Colorado on 1 May 2012, snow pack was lowest on record since 1968 and just 19% of average. As a result there was subsequently no snow melt and soil moisture or runoff. All the heat went into desiccating vegetation and raising temperatures and there was no snow melt or evaporative cooling effects to be had. In their Fig. 1 they show that on 1 May 2012 the widespread drought was already present throughout the entire Southwestern parts of the country, and this of course translated into extreme fire risk by June when major wildfires caused havoc in Colorado and burned over 600 houses. The dryness and heat appeared to spread eastwards, even as Colorado had some rains in July. But none of this is mentioned.

In the experiments performed with climate models, no indication is given that the model used or the forecast results from several other models, have any skill or utility at the task set them. The distinctive La Niña pattern in 2011 giving extremes of dryness in Texas and wetness further north was not simulated or predicted either! In the lower 48, it has been distinctly wetter after about the 1970s in all seasons other than winter, but none of the models simulate this. Not one! The model biases are not dealt with and their skill, or lack of it, is not given. They are not shown to be appropriate to the task at hand. There is a complete failure to provide any reasons to believe the results. Moreover the experiments are woefully incomplete. SSTs [sea surface temperatures] were specified but no attempt was made to include soil moisture, snow cover anomalies, or vegetation health, for instance.

It is well established that all events such as the one nominally analyzed have a large component from natural variability that create anticyclonic conditions (which are better seen at 300 hPa not 500 hPa). The question never addressed is what does global warming and human influences bring to that? There is no discussion of evaporation, or potential evapotranspiration, which is greatly enhanced by increased heat-trapping greenhouse gases. In fact, given prevailing anticyclonic conditions, the expectation is for drought that is exacerbated by global warming, greatly increasing the heat waves and wild fire risk. The omission of any such considerations is a MAJOR failure of this publication.

There are several other things that are quite misleading. They deal with the “morphology” of the drought. Certainly that should include a comprehensive description of the factors involved, including actual soil moisture, snow cover, vegetation, and evapotranspiration, for instance. This includes what they call the “proximate cause” but which is really just part of the description and not a “cause” at all. Yet that is quite incomplete.

Several aspects of the report comment almost as if the extreme dryness and heat did not really happen. It could not be simulated or predicted and no cause can be found, so did it really happen? The paper fails to offer a plausible way in which the whole drought evolved and the role of humans, and climate change, and even natural variability.

The fact is that such events have happened somewhere on the planet every year in recent times. Perhaps we could go back to the 2003 heat wave in Europe. Years of drought in Australia led to the exceptional drought and heat waves and wild fires in February 2009 in particular, and again in 2013 (with record flooding in 2010-11); Russia in 2010, and the US in 2011 and 2012.

Some things were mixed and turn out to distort the results: comparing the summer of 2012 with the whole year of 1934 and 1936. Both of the latter years were dryer than 2012 for the 48 contiguous states for the year as a whole. Why the focus was on the Great Plains (which were not defined) is not clear. In some Figures, Colorado is included but it is not a “Great Plains” State.

So wrt global warming and increased greenhouse gases, say we have 1 W m-2 of extra heat for, say, the first 6 months of 2012 and it has no where to go because there is no snow pack or moisture. That is 0.1 W m-2 per sq foot. I use a sq ft as this is about the size of a small microwave oven. So if we add this up for 180 days, it amounts to zapping everything with a microwave oven (every sq foot) at full power for 36 minutes. (That’s at 700 W). No wonder we had major wild fires here in Colorado. The report fails completely to deal with the cumulative effects of drought on heat and wild fire risk.

89 Responses to Yes, Climate Change Is Worsening U.S. Drought — NOAA Report Needlessly Confuses The Issue

  1. Jim says:

    Thanks. I should have known you’d be all over it with a monster post.

  2. Camburn says:

    It would be wise to stick to the evidence, as provided by NOAA, rather than conjecture.

    The 2012 drought was expected for many years by farmers, and in fact was overdue.

  3. M Tucker says:

    A random event! This is why there will never be a climate “Pearl Harbor.” Because the extreme weather events will be separated out in time and space and you will never get consensus from scientists. Even if the 2012 drought is a continuation of the 2011 drought and that was preceded by a smaller drought in 2010…time and space baby. You will always have winter coming between the summers of drought. Winter will always bring some rain and snow and the time lapse will allow people to put it out of their minds. Oh, a West Texas farmer will remember but the scientists will never agree that climate disruption is the cause. Maybe this year Iowa will get just enough rain while West Texas and New Mexico suffer again. Or, maybe Dubuque will get hammered by unprecedented rain like Louisville, KY 2009. Maybe the Southeast will have another summer drought but they got some rain this past winter so it will not be seen as a continuation of a prolonged drought. Then there is always natural variability that creates doubt and makes consensus very problematic. Time, space and natural variability. The people will just say, “It’s just the natural cycles of the weather.”

    The media will always have trouble with scientific reports. Look at the trouble they are having with the Marcott et al. paper. Look at the report in the Economist. And, after all, the majority of news nowadays is all about entertainment so you have to bring in the dissenting opinion. You gotta keep it fun. You gotta have controversy. So the majority of the public will not really know what to believe and we will continue with business as usual.

  4. Michael Tanton says:

    Climate change “loads the dice” and makes extreme weather more likely to happen.

  5. Sasparilla says:

    Thank you for the extensive analysis Joe, I was thinking of you and what’d you say when I heard the headline on the radio today – had to check that News Corp wasn’t in charge of my radio since it was perfect for them – and also noting that this was a great “keep the natives calm and climate change on the back-burner of their concerns” headline – perfect really.

    Frankly I was 1/2 expecting a bunch of old retired GOP members (from these organizations) to be putting this out (like the couple of old climate denying ass-tronauts that come out every once in while).

  6. Sasparilla says:

    Well said M…if you want to diffuse virtually any of these climate change affected 100/1000 year conditions – just have your Country’s leading scientific organizations come out and say it was a “one time freak of nature not connected to climate change”…

    The perfect keep the natives calm and put climate change concerns on the back burners of their brains headline – if this was the former Bush administration I’d have been sure it was manufactured/created for just that purpose.

    With this administration its hard to square (I don’t think we’re at the point where this administration would intentionally do something like this – just to diffuse rising public concerns over climate change).

  7. catman306 says:

    When something needs to be said, Joe will say it well.

  8. Daniel Coffey says:

    Climate change connected to drought, how could it be? This is the frailty of language when terms are selected with vagueness in mind. Global warming and a warmer atmosphere and oceans are pretty easy to understand in relation to drought, since the physics are pretty simple. The obsession with direct causal linkages is really a waste of time and one which engages doubters in their strongest position – as doubters. When the burden of proof and the burden of persuasion and the obligation to produce evidence beyond a particularly high standard is adopted, the other side always wins the argument.

  9. Mulga Mumblebrain says:

    Ohm Catbum-I really missed you! The drought was ‘overdue’, was it? Please explain how so?

  10. Douglas says:

    Who ya gonna believe — my model or your lyin’ eyes?

    Seriously, what I find interesting is that most of the arctic ice loss/slowing Rossby wave studies I’ve read have been based on real-world observations. If these changes are not captured in a particular model, maybe the model is wrong!

  11. SecularAnimist says:

    M Tucker wrote: “The media will always have trouble with scientific reports.”

    They don’t seem to be having any trouble misrepresenting this one.

  12. Merrelyn Emery says:

    Models do not come in ‘right’ or ‘wrong’. They are to various degrees adequate/inadequate, inclusive/exclusive of relevant variables. Modelling is inherently based on probabilities, ME

  13. This is from the Hoerling report summary and, as far as I can tell, is the only reason he and his team give for saying the drought is not connected to global warming:

    ” • Neither ocean states nor human-induced climate change, factors that can provide long-lead predictability, appeared to play significant roles in causing severe rainfall deficits over the major corn producing regions of central Great Plains.”

    Note that it says “can” provide long-lead predictability, not “provide” long-lead predictability. Think for a moment about the great Arctic meltdown of 2012. The IPCC’s long-lead predictability for that season’s ice extent/thickness was for around 2075-2095. Then all of the sudden it happened.

    As Trenberth pointed out here, the conditions for the sudden-onset drought were preset by various climate change-caused and-related factors then, wham, the drought hit.

    My own contention as a non-scientist but careful observer of developments is that we can expect many more such sudden-onset, essentially unpredictable events and developments in the coming years. Everything is out of whack — no one knows how the jet stream will behave, when or to what extent is is likely to meander as it continues to slow down. What happens when the southern oscillation shifts? When and where can we expect the heat content of the oceans to produce specific effects such as the mass die-off of temperature sensitive marine organisms that will in turn change the carbon cycle? Is there a tipping point beyond which the CO2 uptake of the oceans will drop precipitously? And, of course, how much CH4 and CO2 will come whooshing out of the permafrost, and how fast?

    In short, we can probably pretty much toss all the old models about what will happen and when — we’ve destabilized the system and entered the era of global weirding, climate chaos.

    For Hoerling to pretend that events such as last summer’s drought are not connected to continued radiative forcing, or not connected to each other is just silly. And for him to publish such information as “fact” that the media can run with is irresponsible.

  14. Joan Savage says:

    Thanks for your thoughtful approach.

    You touched on what seems to be a key issue; the gap between out of date long-lead climate models and the immediate need for seasonal meteorologic prediction.

    There are some ways of better predicting what you call chaos, but we need to get onto that task, pronto.

  15. BlackDragon says:

    Completely agree. The only “facts” we can pin down here so far: 1) this drought took place within an already destabilized climate system, so it must have been affected to some degree by these new factors, and 2) our models are already missing all kinds of things, at least as far as onset speet – the arctic meltdown, the change in the jet stream, and so on.

    Things are well into the weird, and I agree strongly that coming out so quickly with any “this couldn’t be climate change” is extremely irresponsible. At least give this a reasonable length of time for real analysis. We haven’t had enough time to say what all the factors were, that is certain.

    Also, it would seem wise to wait a few more years, or even one more summer, and see if this is could be a longer term regional drought, before thinking we have a handle on all the cause and effect.

  16. Merrelyn Emery says:

    It isn’t just that factors may be missing, the whole basis and methodology of modelling cannot adequately deal with a systemic response, ME

  17. BlackDragon says:

    Sorry, I meant “missing” as in “not predicting” – not missing as in missing variable factors.

  18. jyyh says:

    Well, duh, it’s pretty hard for a drought to be unprecedented with these:

    so these types will have some ways to avoid the obvious conclusions at least for the next 17 years, ‘we’re sorry we seem to have entered a repeat of MWP, we’ve no idea how that happened since the hockey stick’

  19. Right On, ME and others. Last year when the great Arctic meltdown happened, somebody — Wadhams? — said we (climatologists and the climate-hawk community) need to rethink everything. The more I learn and think the more I realize just how far up the creek we are and how far from our paddle.

    Joan Savage — if you know better ways to predict chaos, would you mind sharing.

    One thing I do know is that diversity is the key to adaption in stressed ecosystems. How that is applied — other than locally — I’m not sure at the moment. But let’s start thinking about it.

  20. rollin says:

    The speed of climate change and it’s unforeseen effects are causing a scientific lag. By the time something has been studied, analyzed, written, peer reviewed and published, climate has changed.
    Add in the delay to any climate action and we are truly “fighting the last war” as far as stopping and reversing global warming.

  21. Edith Wiethorn says:

    As set forth in this BBC Documentary summarizing scientific observations – the interaction of global warming from greenhouse gasses with solar dimming from particle pollution would explain the shifts in macro weather patterns that have caused extreme droughts.
    49min BBC Global Dimming Documentary About Geoengineering & Global Warming
    Uploaded on Dec 31, 2011
    A BBC documentary about how unintentional increased reflectance due to man made pollution has actually hidden the affects of increased carbon dioxide in the atmosphere.
News & Politics

  22. BlackDragon says:

    I think our stressed ecosystems just need a vacation from their problems.

    Diversity is the key to adaptation, but are we ready for the kind of diverse perceptions of reality that are necessary to seize the adaptations that will enable the leap to the other side?

    The Supreme Illusion will chaotically change and require us to rethink everything about how we play The Cosmic Game. I predict severe unpredictability, and fun times will be had by all. Keep light, and see you in flight!

  23. Anne van der Bom says:

    So the GOP will conclude that God’s to blame. How convenient.

  24. Mulga Mumblebrain says:

    It looks awfully like Hoerling is peddling his wares in public, hoping to be picked up by some rich suitor, like Fox News, as a ‘consultant’. That may be my habitual cynicism, but one can never be too thin, too cynical or too drunk, I find.

  25. Mulga Mumblebrain says:

    Very true. If global dimming was lessened, say by China moving quickly to renewables and dumping coal, in order to clean up the atmosphere as the holders of the ‘Mandate of Heaven’ are supposed to do, in order to succour the people, then we’d be even deeper in the liquid doo-doo. In fact we’d need a periscope to discern just how deep we are in it.

  26. Vincent Pawlowski says:

    While precipitation is more difficult to predict than global temperatures, generally, climate predictions are getting more skillful. The trend toward more extreme weather events will continue. So will the arguments.

    Overall, expect the drought to continue in most of the mid-west and southwest. 2013 is already behind in precipitation in many areas. This is because climate change makes the water cycle more extreme as more energy circulates. The missing Arctic ice also adds to the extremes. Overall, higher evaporation rates can make heavy rainstorms heavier, and droughts deeper and longer.

    Then, when rain finally falls, it often comes as a violent downpour it doesn’t do much to help crops or other plants. Instead of gently soaking into the soil, heavy rain can cause flooding, but then all that extra water quickly runs off into rivers to be carried back to the sea.

    Even if global warming weren’t affecting the drought, the increased temperatures would. Excess evaporation dries out soils and plants more. Think about watering your lawn on a scorching hot afternoon. Some of the water from your sprinkler evaporates before it even hits the grass, and the rest has little chance to soak into the soil before it moves back into the air.

  27. Joan Savage says:


    Apologies for a longish answer.

    Here’s the cut to the chase part:
    With climate change, the pattern shifts are developing. Putting the new data through various kinds of multivariate stats is basic, and I’d hope they’d also use non-parametric analysis.

    When I was a grad student in ecology, my adviser sent me to a presentation on chaos by the famous Mandelbrot. It wasn’t as mathematically brilliant as billed, though the graphics were and are awesome. The chaos graphics illustrate that even “chaos” develops pattern at some level of iteration.

    In ecosystem development it is typical for the inception of a new system to begin with what humans call disturbance – tumultuous conditions with big shifts in selection pressures. In contrast, what humans think of as ‘normal’ are just adaptations to something or other.

    High-quality seasonal weather forecasting from the National Weather Service ( may have already picked up on changing factors that might not yet be incorporated in Hoerling’s long-lead climate model.

    An identified element to include in both weather and climate modeling is the increased amplitude of the Rossby waves of the formerly-circumpolar jet stream. That is an important new pattern in the new normal.
    On an individual human scale it can feel chaotic.

    Taking a decadal scale view, even the Rossby wave factor is likely to be complicated by yet other factors as added heat further alters the system.

  28. Ryan says:

    I’m liking the reaction at WUWT.
    One model fails to show a scenario?IT MUST BE IMPOSSIBLE!!!
    As contrasted to their usual:
    Many models show something is likely? MODELS ARE SO DUMB.

  29. Joan Savage says:

    Not NOAA, just Hoerling.

  30. David Goldstein says:

    We all know the upshot here: A less than careful study is turned into much-less-than-careful headlines which is than seen by millions of eyeballs (most of which do not bother to read beyond the headline in any case). So- voila – in one careless stroke, millions are reassured that the droughts in the U.S. have nothing to do with AGW. Meanwhile. Joe and the folks over at Skeptical Science, and perhaps a few other sources will write accurate contradictions to the misleading headlines- but how many of the millions will ever know? (or care)

  31. gomezjunco says:

    Carbon pollution puts the weather on steroids. It greatly increases our risk of extreme weather like heavy storms, droughts, and heat waves.

  32. Camburn says:

    It is Camburn, thank you.

    There is an approx 19 year cycle to drought conditions. Some droughts are worse than others.
    The 19 year cycle is part of a longer 80 year cycle.
    I farm. The types of weather that some folks attribute to climate change have ALWAYS been part of the ag discussion.

    The Ag community is well aware of these cycles. The general public, who do NOT rely on climate/weather seem to not be aware.

    Most of my ag friends just shake their heads and smile at how little city folks know.

    Heck, there is even a 400 year cycle to all of this.

    Ivory towers are not good places to learn real world observations.

  33. Joan,

    Thanks for your answerer, and I get it. My question still is — using the Rossby waves as one example — how can we predict the unpredictable in our disintegrating complex system. Let’s say, for example, that Jennifer Francis’s concept becomes widely accepted and we start trying to model the phenomenon. My guess — and, obviously it’s only a guess — is that there are so many possible influences on the Rossby meanders that it’s impossible to predict, on a regional or even a continental scale, when and where the next blocking pattern will develop.

    Influences could include the continuing disintegration, at unpredictable rates, of the temperature differential that drives the jet stream, flips in the northern or southern oscillations, and so on. Meanwhile, longer-term patterns driven by long-term forcings such as the drying of the continental interiors, increased atmospheric water vapor, growing ocean heat content and expansion and so on would override the blippy short-term stuff like sliding Rossby waves only in fits and starts that, while measurable as steady progress (or degradation) over centuries would seem erratic on a decadal scale.

    Just a guess. I’d like to correspond — you can reach me through my web site if you’d like.

  34. rollin says:

    NOAA and NASA are being throttled by the executive branch. It’s what we are not hearing and what is not being pursued that are the important things. Agenda driven science is not science nor does it reveal reality.

  35. Hoerling’s been at this before. Below is a whole page of articles from Dot Earth where he weighs in on extreme weather events, including Hurricane Sandy, and disses any global warming connection — attributing everything to “natural cycles” and “chance occurrences.” Sound familiar? Yes, but not coming from a scientific organization like NOAA. (On the other hand, wasn’t NOAA down there in the Gulf trying to cover up the damage from the BP spill?)

    The occasional outlier climate scientist isn’t so much the problem — although Hoerling’s clearly wrong in my view. The problem is the corporate media loves Hoerling, so every time remarks that amount to denier nonsense comes out of his mouth it’s all over the front page. Discouraging for those us who are trying to wake up the public to the danger it faces.

  36. Camburn says:

    Sir William Herschel did not know the cause of the wheat production decline in relation to the sun, but he documented that it is a very real world relationship.

    Part of that cause is now somewhat understood. TSI varies very little from the sun. But the variation in the light bands is huge. This affects the jet stream, which affects the weather. The long term pattern of the sun affects the jet stream long enough to change climate parameters.

    Don’t you really think it is time to look at the “total” picture, and not just a fractional part of it?

  37. I suspect you’re right. Got any links so we can read up on it?

    I wonder if “Go with the Science Obama” is somehow related to that other guy, “All of the Above Obama?”

    Ya think?

  38. Jan Freed says:

    Yes, I follow his career with interest.

    The deniers claim that “nay sayers” in the science community will be drummed out of their profession; this will NOT occur (though I won’t invite Hoerling to my party because I think his study is poor). Hoerling may just “drift” out of his position for other reasons.

  39. Joan Savage says:

    A time line for Texas droughts taking it up to Fall 2011.

    Of the thirteen droughts since 1885, Texas droughts typically last 2-4 years, with the exceptional drought of record being the seven year drought, 1950-57.

    With that in mind, Texas could be entering a fourth year, counting from 2010 inclusive. 2012 was identified as breaking the previous record for severity in a single year. This is already among the longer drought for Texas and it has beat the 1950s for single-year severity.

    That’s not proof of climate change, in itself. Being more specific about the drivers in this drought is where the issue lies.

  40. Jan Freed says:

    So, can you find a prediction of this drought anywhere by farmers, actually written down?

    Ivory tower? Actually, scientists study the real world far from the tower, in far greater detail and extent than farmers who are busy farming, to reach new conclusions beyond “folk wisdom” (which is sometimes rife with nonsense).

    Their conclusions are thereby based in their real world observations.

    So, when we have had 332 CONSECUTIVE months of temperatures higher than pre-oil averages


    and that beats odds of 1 divided by the number of stars in the universe, don’t be surprised if we have more frequent and extreme droughts.

  41. Susan Anderson says:

    Thanks for the straight-up on this. Sadly, this will be cited out of context and without the details and blow up the vast hot air balloon, obscuring the light.

  42. rollin says:

    Good luck to you farmers out there, droughts always have devastating effects. Climate change does predict more frequent and more severe droughts in certain areas, but from a daily and local point of view it is still a drought. The trend toward further desertification is clear but how long this will take and the details of how much are not clear yet. No one can say this will be a three year drought or a fifty year drought. One thing you do have on your side is atmospheric pollution, global dimming from aerosols has reduced over-all evaporation rates due to decreased sunlight reaching the surface.
    Again, good luck and hope you get enough rain.

  43. rollin says:

    Best place to start is James Hansen’s “Storms of My Grandchildren”. Usually some of the local libraries carry it.

  44. Camburn says:

    Actually, the atmosphere has become more clear since 1996 as confirmed by NCAR. The idea that there is dimming is not correct.

    As a farmer, I deal with cycles which are not only folk lore, but well established.

    An example is the 400 year cycle.

    Even within that cycle there are shorter cycles which are well documented.

    Before climate became so stupidly politicized, Ag universities were diligently studying cause and effect. It is of huge importance to a farmer, who risks tremendous amounts of capital annually to understand natural cycles etc.

    A lot of folks may think we are a bunch of dumb hicks who tote guns etc. That could not be further from the truth.

    We embrace new tech, we use the tech so that we can survive economically and feed the masses in the city.

    My Grandpa was a smart man, and watched the Greenland high for signals in the 1930’s. Way before computer models, he had certain parameters well in hand.

    I would advise all who read this board to not ignore that “folk wisdom”.

  45. Camburn says:

    I hate to break the news to you, but the last 50 years have been the MOST drought free years out of the last 200 years.

  46. Camburn says:

    The earlier droughts in Texas during the 1700’s put the current drought to shame as a period of wetness.

    Droughts come, and droughts go. We do not know many of the causes, but we do know they happen.

  47. Camburn says:

    Best place to start is with the published literature.

  48. Camburn says:

    When you farm in the 21st Century, you use all tools available to mitigate risk.

    One of those tools is knowledge.

    Prof Trenbeth is a swell fellow, but he is clutching at straws in regards to his response.

  49. Camburn says:

    I posted some links to literature in responses above.

    The authors of the NOAA study are correct, in that to tease a climate change signal out of the 2012 drought is about impossible.

  50. Wrong question. They’re asking the wrong question if they are trying to “tease a climate change signal out of the…drought.”

    This ordinary citizen is going to challenge the brass at NOAA with a version of the right question. For 800,000 years CO2 levels varied between 180 and 280 ppm, roughly corresponding with glacial and interglacial periods respectively. During the Holocene, prior to the industrial revolution, the levels varied between 260 and 280.

    It seems reasonable to assume that the weather during the Holocene, the ALL of the “natural cycles,” and “freak occurrences” were driven or in some way conditioned by those CO2 levels. Put another way, what’s “natural” is what is determined by the amount of CO2 in the atmosphere.

    Now we live on a planet where the atmospheric CO2 levels are at 400 ppm. How is it possible that ANY weather event or climate development is not connected to that reality?

  51. Camburn says:

    MIS-5 is documented to have had temps approx 5.0C warmer than present, yet CO2 levels were approx 280ppm.
    The Arctic Sea was ice free during the summer, most of the Greenland Ice Sheet melted.
    The orbital parameters were similar to present.

    There are just a lot of things about climate that we just don’t know yet.

  52. Joan Savage says:

    You could have gone even further back in Texas history to severe droughts in the 1600s and 1500s, as indicated by tree ring study.

    More is known about drought factors than in the past, particularly the ENSO cycle.

    I am not as optimistic as you about droughts simply going away. The droughts are obviously affected by heat and the distribution of atmospheric moisture, and those have changed, so droughts are likely to change.

  53. Superman1 says:

    “This is why there will never be a climate “Pearl Harbor.”” Agreed; that’s the wrong analogy. Climate change is characterized by once extreme events increasing in frequency and magnitude as temperature increases; it is an integral phenomenon.

  54. rollin says:

    5.0 deg C? No. 2-3 deg C at the poles maybe, that is where the ice data was taken. The poles always show the highest temperature extremes and are not the global temp.

    As a climate change denier, why are you picking evidence of previous climate change and trying to prove some pre-determined point? The science has been done. Change is happening.

  55. Roger Lambert says:

    “The 2012 drought was expected for many years by farmers, and in fact was overdue.”

    Bullshit. Believe it or not, scientists actually have access to long-term records and this curious branch of mathematics called statistics. No doubt news to you.

    These clearly show that the climate phenomena we are beginning to experience is NOT part of a natural cycle, and the droughts we are seeing are well beyond what would have been expected.

    As a farmer, you must be well-acquainted with various types of manure, but you need to get your head out of it if you are going to stop making unsupportable assertions about climate.

    And feel free to chastise the large and growing numbers of farmers in Oklahoma and Texas who have lost ancestral farms due to these droughts – I am sure they will appreciate the opportunity to learn from your wisdom.

  56. Joan Savage says:

    I left a previous reply that went into moderation before vanishing entirely.

    Here’s the gist.

    I hope I’m not asking too much from multivariate ANOVA, statistical regression, or non-parametric analyses, but that’s what they are good at, looking at phenomena where we admit we don’t have a full roster of known factors, or in some cases don’t have a strong basis to believe there is a normal distribution (statistical distribution) of events.

    Back when the climate modeling was new, there was a lot of such sorting out to get down to a few measurable factors sufficient to build a model with predictability. I was around people who did the real-deal on environmental modeling of several kinds. I took the stats courses and didn’t do the hands-on, so I’m an informed critic, not a practitioner.

  57. Mulga Mumblebrain says:

    Camburn, you really seem incapable of grasping the simple fact that the global climate regime is destabilising more rapidly than at any stage in recent human history, and any stage in planetary history save after meteor and comet impacts. The history of drought in the USA over the last 50 or 200, or 2000 years, for that matter, is now rendered almost meaningless as a predictor of future events. Is that really so hard to grasp?

  58. Mulga Mumblebrain says:

    It reads like you’ve been ‘Chasing the Dragon’ Black Dragon. Time to return to this dimension, I’m afraid.

  59. Mulga Mumblebrain says:

    Now you’re just making yourself look silly, Camburn. Your one-eyed approach doesn’t impress. Going back to the 18th century, even before the Industrial Revolution got going, is simply daft. And to imply that climate scientists take no note of solar influences, that have the greatest effect on our planet’s climate, is simply the crudest denialist gibberish, worthy of Rush Limbaugh. Must do better.

  60. Mulga Mumblebrain says:

    The same thing happens in Oz. One maverick, on the make or driven by Rightwing ideology, speaks out against the consensus, and he becomes an instant MSM darling. The Murdoch sewer naturally, is the worst offender. Our MSM could hardly become more malignant and malevolent than they already are.

  61. Mulga Mumblebrain says:

    There is nothing ‘careless’ about it, I’m very much afraid. This stuff is carefully and coldly calculated.

  62. Mulga Mumblebrain says:

    To concur with your casuistry, one must believe that increasing the atmospheric concentrations of known greenhouse gases by over 40% in the last 200 years, has not, and can not, have any effect on climate and weather, and that is plainly in Rush Limbaugh territory. Perhaps we should start calling you ‘Little Rush’?

  63. Mulga Mumblebrain says:

    And the global human population then was precisely how many? And how rapidly had the world moved into this climate regime from that immediately prior?

  64. Camburn says:

    Ah yes, the curious use of stats.
    That is why I posted a link to published literature showing the SLOWING of drought conditions in the US.

  65. Camburn says:


    We do NOT know a lot about the sun and its effects. Dr. Leif Svalgaard will admit this with no remorse.

    There are lots of foolish correlation to sun ideas out there, and he has picked them apart with known knowledge.

    Sir William Herschel, might be long gone but his literature still stands.

  66. Camburn says:

    My good fellow, your perception is 100% wrong in regards to my understanding of climate, implications etc.

    I live, eat, breath climate study. It has tremendous implications on whether I am a failed business or a successful one.

    I deal with agronomic scientists on an almost daily basis. I also deal with climate scientists that I have come to know.

    Thank you for the chuckle.

  67. Camburn says:

    No, it is potentially you who could wear the name Rush Limbaugh proudly. It would seem both of your knowledge about the metrics of climate are similar, but with a different political bend.

  68. Camburn = TROLL ALERT, folks.

    Move on and ignore the trumped up sci-fi.

  69. Mulga Mumblebrain says:

    How do drought conditions SLOW? It’s like speaking of a car INTENSIFYING.

  70. Mulga Mumblebrain says:

    Herschel’s literature stands, but is almost entirely irrelevant to our current predicament. The science most germane to our current circumstances commenced with the likes of Joseph Fourier and John Tyndall, and concerns not the peculiarities of solar activity, but the workings of greenhouse gases. You seem to me to be simply dismissing their crucial importance ie denying reality.

  71. Mulga Mumblebrain says:

    Interesting but irrelevant. The current crisis is one caused by anthropogenic emissions of greenhouse gases, not variations in solar activity. Do you actually deny the greenhouse effect, that CO2, CH4 et al are greenhouse gases, that their levels in the atmosphere have risen by 40% in the last 200 years and that that occurrence is the prime driver of the climate change that is rapidly unfolding. Or do you simply deny them all, or, perhaps, soft deny by inferring that these facts are somehow of no or little consequence?

  72. Mulga Mumblebrain says:

    Camburn lives in the 18th century, and imagines that Herschel is an up to the minute authority. It is a peculiar form of casuistry to imply that the scientific understanding of the 18th century is somehow superior to that of today, as if three centuries have brought us no advances in scientific understanding. Also strangely unconvincing is the idea that droughts in the past, when atmospheric concentrations of greenhouse gases were 40% less than today, are somehow absolutely alike to those today, thereby refuting the anthropogenic climate change theory. One could just as comfortably argue that conditions were considerably colder in 1816, that, in fact, there was no summer in the northern hemisphere that year, while ignoring the eruption of Tambora, and put it all down to some sort of abrupt, short-lived, solar activity minimum. When you start, as Camburn plainly does, with the rigid belief that anthropogenic climate change caused by the emissions of greenhouse gases is not, perhaps can not be, occurring, then you have to turn the scientific method on its head, and make the facts fit the theory. Camburn doesn’t set out to falsify or disprove his dogma-like the Jesuit he knows, a priori, what the truth MUST be, so he then twists and distorts the facts to suit his beliefs.

  73. Mulga Mumblebrain says:

    Yes, but we know that the greenhouse effect warms the planet, and that atmospheric levels of these gases, principally CO2 and CH4 have risen by 40% in 200 years to levels unknown for hundreds of millennia, yet you dismiss that as irrelevant. How odd.

  74. Mulga Mumblebrain says:

    It certainly looks that way. I must be bored.

  75. FrankD says:

    “most of the Greenland Ice Sheet melted”
    As I understand it Greenland’s contribution to SLR during MIS-5 was no more than 2m, meaning less that 1/3 melted. Not really “most”, is it?

    “The Arctic Sea was ice free during the summer.”
    Again, the papers I’ve seen suggest that while the North Atlantic was much warmer, the Arctic Ocean was probably colder and would have had good sea ice coverage. Not really “ice free”, is it?.

    “The orbital parameters were similar to present.”
    Obliquity (axial tilt) was a little greater, orbital eccentricity was substantial more, perihelion occurred in the NH summer, not the NH winter, summer insolation the North Atlantic/Northern Europe was as much as 10% higher than today. Not really “similar to the present”, is it?

    “a failed business or a successful one” – There are many examples of technical incompetants who were successful businessmen, due to good marketing or plain dumb luck. You haven’t provided enough information for us to exclude those possibilities. Contrary evidence appears to be accumulating…

  76. Merrelyn Emery says:

    I know this study doesn’t help but I think most ordinary people all over the world now know what the score is. Enough of the real stuff gets through to reinforce the normal human response of ‘seeing is believing’, ‘feeling is believing’. We know that denial is fading, apart from the paid and organized perpetrators, and renewables are up, up and away. It’s time now for grand popular action to reinforce the growing grass roots conviction, ME

  77. Merrelyn Emery says:

    Yep Joan, I think you are asking too much. I know my way around a few stats and most of them are inadequate to deal with the functioning of systems. They are built entirely on synthesis from individual variables which can never approximate a systemic response. Maths for systems have been available for quite a while now but are up against the orthodoxy of reductionism, ME

  78. Merrelyn Emery says:

    It has become obvious for some time now. He (I’m sure) is just unveiling, parading, the latest fashion in denial – good old folk wisdom. Hope you’ve had a drink or n by now, ME

  79. renewable guy says:

    Camburn says:

    April 13, 2013 at 11:56 am

    Actually, the atmosphere has become more clear since 1996 as confirmed by NCAR. The idea that there is dimming is not correct.

    As a farmer, I deal with cycles which are not only folk lore, but well established.

    An example is the 400 year cycle.
    The article you have referenced is talking about cycles but is using data to try to make a correlation in the past. But the past did not have 40% more co2 added to its atmsophere. There is an increased radiative forcing from co2. Why wouldn’t you take that into account? The article below talks about net radiation, yet if I understand you correctly, you are saying the net radiation isn’t a factor. Which is what increased co2 does to the land and oceans.

    The 400-Year Wet-Dry Climate Cycle in Interior North
    America and Its Solar Connection

    Aridity could be caused by either decreased precipitation (moisture availability and atmospheric
    circulation support) or increased evapotranspiration (net radiation and temperature). Either of these
    changes could occur either during particular seasons or throughout the year.

  80. Spike says:

    “There is no discussion of evaporation, or potential evapotranspiration, which is greatly enhanced by increased heat-trapping greenhouse gases.”

    Quite astonishing really – like others i wasn’t surprised when Hoerling’s name cropped up. I recall his comments in the NYT about Hansen’s documentation of the massive rise in actual +3SD heatwaves and resulting worsening droughts:

    Dr. Hoerling has published research suggesting that the 2010 Russian heat wave was largely a consequence of natural climate variability, and a forthcoming study he carried out on the Texas drought of 2011 also says natural factors were the main cause.

    Dr. Hoerling contended that Dr. Hansen’s new paper confuses drought, caused primarily by a lack of rainfall, with heat waves.

    “This isn’t a serious science paper,” Dr. Hoerling said. “It’s mainly about perception, as indicated by the paper’s title. Perception is not a science.”

  81. Again, where Hoerling blows it: There is no such thing as “natural climate variability” that doesn’t account for the CO2 and CO2e contents of the atmosphere. Of course there is variability — but within parameters which are determined by the factors such as the overall radiative balance of the system. That, it turn, is determined by the primarily by greenhouse gas content of the atmosphere and secondarily by other factors.

    Within those parameters variability happens— lots of it as we continue to energize the system. In fact, a lot more “variability ” is happening than has happened for at least 11,500 years, and quite possibly the last 800,000 years or more.

  82. Camburn says:

    “The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 °C warmer than today.”

  83. Joan Savage says:

    Please name the stats / maths that you have in mind.

  84. thanes says:

    Oh someday they’ll know. Fat lotta good….

  85. thanes says:

    Do you dress up like Wilford Brimley when you sit down to assume this persona?

    Is this going to be a new paid troll variant? It may be the most annoying one out there. I’d rather they go back to the disillusioned hippie, Mememine

  86. velvetfish says:

    What is abundantly clear is that within the past 100 years the global mean temperature has risen 0.8°C or 0.008°C/yr.

    To find any period in Earth history in which the rate has risen anywhere near as quickly one must go back to the Paleocene-Eocene Thermal Maximum 55 mybp during which the mean global temperature rose about 6 °C (11 °F) over a period of approximately 20,000 years. That is a 0.0003 °C/yr increase (.00055 °F/yr.

    Thus, we reach the undeniable realization that currently the Earth is heating faster than 26 times faster than the fastest rate of heating in the past 55 million years. If one recognizes that most of the heating has occurred in the past 20-30 years rather than the past 100, according to satellite and ground based measurements, the rate is probably closer to 100 times faster.

    During the past 100 years the amount of solar radiation reaching the earth has not increased anywhere near 26X, much less 100 times, nor have there been any changes in orbits that are larger than 26-100 times what they were 100 years ago. Nor have geologists discovered vast undersea ranges of previously unknown volcanoes. However, we do know that the amount of carbon dioxide in the atmosphere has doubled and is approximately what we would expect if we summed either the amount of fossil fuels mined or the amount of fossil fuels burned over the past 100 years. We also know that atmospheric forcing by carbon dioxide could and almost certainly does explain virtually all the observed heating. Since the effect is cummulative and we are burning more fossil fuels faster than ever, we can expect the worst is yet to come.

    When one realizes that during the Paleocene-Eocene Thermal Maximum virtually the entire then existing mammal fauna of North America went extinct to be replace by smaller species, most fossorial and entire ecosystems disappeared.

    Earth to Houston. We have a problem! Ignore it your peril.

  87. Bill D. says:

    It’s probably just a coincidence that we keep getting 100-year droughts, floods and storms almost every year these days. So let’s just keep our heads firmly buried in the sand; you know, the stuff we used to call “soil?”