I noted in this post that the GISS data since 1975 show a seasonal pattern (an annual cycle) in spite of being temperature anomaly. This is because they’re anomaly relative to a 1951-1980 baseline, so the seasonal pattern which is subtracted from the data is the average annual cycle from 1951-1980. The annual cycle in global temperature isn’t perfectly constant, and the difference between the annual cycle at any given moment and its average for the baseline period is detectable in the GISS data.
DeepClimate pointed out that the trend is different for different seasons. He linked to this interesting graph of trends by month of the year for data from 1979 to 2008. It’s not equivalent to the annual cycle in GISS data, which depends on comparison to the average annual cycle 1951-1980 — but it is a reflection of the same phenomenon, namely that some times of year have warmed more or less than others. For the 1979-2008 period studied by DeepClimate, it’s the later months of the year (northern hemisphere autumn) that show the greatest warming in the NASA GISS data, and in fact there’s a hint of the same behavior in the HadCRU and NOAA data (but not as pronounced as in GISS data). Note also that UAH is definitely the oddball, with an implausibly low trend for 8 months of the year and implausibly high difference in trends between different months.
We can also investigate the issue by seeing what the annual cycle looks like in GISS data, which will of course actually be the difference between the annual cycle and its 1951-1980 average. We can even call this “annual cycle anomaly.” First I’ll take GISS data from 1975 to the present and subtract the linear trend, so the global warming trend won’t interfere with our analysis. Then I’ll take 5-year segments of those residuals, starting with 1980-1985 and ending with 2005-2009.667 (the last segment is 4 months shy of 5 years), and estimate the annual cycle anomaly by fitting a 2nd-order Fourier series.
Here’s the result for GISS global temperature: colors code the decade (blue for the 1980s, black for the 1990s, red for the 2000s) and solid lines are the first 5 years of each decade, dashed lines the second 5 years of each decade, and I’ve shown two full repititions (two years) of the cycles.
We see right away that for most of the 5-year spans, the annual cycle peaks early in the year (winter/spring), showing that winter/spring has warmed more than other seasons compared to the 1951-1980 average. But we also see that the effect had already reached its full strength by 1980-1985. This means that there hasn’t been any further enhanced winter/spring warming since then. In fact, we note that for the 2005-present time span, the annual cycle anomaly is no longer as strong in winter as it was before. For this latest 5-year span, not only has summer warming “caught up” with winter warming, but the autumn warming is now more pronounced.
This agrees with what DeepClimate noted in this comment. He calculates that the warming rates from 1975 to 2008 for winter, spring, and summer are nearly identical while the warming rate in autumn is higher.
I also did the same analysis for NASA GISS data from the northern hemisphere:
The annual cycle anomaly is much stronger for the northern hemisphere than it is for the globe as a whole, although the pattern is the same. But again, it has already reached its full strength by 1980-1985, and again, it peaks in winter/spring until 2005-present, when it peaks in autumn. Again we conclude that there was enhanced winter/spring warming to 1980-1985 but it didn’t increase further after that, and enhanced autumn warming for 2005-present.
And of course, I did the analysis for the southern hemisphere:
The southern hemisphere annual cycle anomaly is much weaker than its northern-hemisphere counterpart, and also shows more irregularity over the last 3 decades. Still, for the most part in the southern hemisphere the cycle peaks just after mid-year, which is winter/spring “down under.” We also note that for 2005-present the annual cycle anomaly is pretty “normal” for the south, but for 2000-2005 there was enhanced late-year warming (NH autumn but SH spring).
It’s quite interesting to note that when it comes to differences between warming rates in different seasons, there’s more to the story than just the oft-quoted “enhanced winter warming” scenario. Both hemispheres show enhanced winter/spring warming culminating about 1980-1985 but it doesn’t continue to grow after that. And the very recent enhanced autumn warming in the northern hemisphere is worth keeping an eye on.
102 responses so far ↓
Slioch // September 15, 2009 at 12:17 pm |
I think phenologists would be interested in this kind of analysis. Phenology is involved with the recording of natural events, particularly in the spring and autumn (fall). In recent years there has been an upsurge in interest in phenology in the UK and many people are involved in recording events, see:
http://www.naturescalendar.org.uk/
We are fortunate here in that records go back for centuries, due an assortment of country vicars and retired schoolmasters and similar eccentrics jotting down such matters as the first swallow or primrose or ripe fruit or falling leaf. No doubt the most appropriate series to use to tie in with such local data would be the local temperature series such as the Central England temperatures.
I understand there are moves to encourage phenology in the US and other places.
Jim Galasyn // September 15, 2009 at 3:57 pm |
Speaking of phenology: Graph of the Day: Timing of Flowering in Greenland, 1996-2008
TrueSceptic // September 15, 2009 at 12:51 pm |
Tamino,
That graph of trends by month really does show something weird going on at UAH, doesn’t it?
Am I correct in thinking they use the same raw data as RSS? Looks to me like some “auditing” is desperately needed! ;)
[Response: They do use the same raw data, but that is not of lower-troposphere temperature. The lower-troposphere estimate is a combination of various channels from the microwave sounding units. Also there are numerous critically important correction factors involved. All in all, satellite-based lower-troposphere temperature estimates are NOT the simple direct measurements some think they are.]
TrueSceptic // September 15, 2009 at 2:32 pm |
Thanks. I did know that the temperatures are not direct measurements but the 2 datasets both purport to show lower troposphere, i.e., the same thing, don’t they?
[Response: Yes they do. But they don't agree on much else.]
Timothy Chase // September 15, 2009 at 5:40 pm |
Interesting views of the data. I guess what I would have expected would have been for it to warm more in the later days of the year early on — perhaps into the early part of January, but as a rule after the winter solstice. Tilt of the sun plus thermal inertia. But even at the onset Deep Climate is showing the peak somewhat earlier in the year, before the winter solstice. Leaning backward rather than forward.
The fact that summer is catching up with winter doesn’t surprise me so much.
After a relatively quick change in forcing to something that remains nearly constant, the difference between winter and summer should grow only so much. Then one might expect difference to partially diminish due to a form of equilibration as the climate system adjusts to the state of being subject to a relatively constant warming trend.
Alternatively, we know that the earth has been subject to a degree of global dimming (from one of Gavin’s papers), but it is too early to tell whether it has been subject to some more recent (~ 1990-2000) global brightening. But if it has this in itself would lead to a decrease in the difference between winter and summer.
Both of these wouldn’t necessarily imply a shift in the annual timing of the maximum rate of warming — but it wouldn’t be that surprising if they did. Nevertheless I wouldn’t have predicted it.
But, believing that there has been some recent global brightening (then even more recent but less significant dimming), I would have predicted the decrease in the difference between summer and winter. Barring that I probably would have expected the decrease in the difference as the result of the climate system “settling into” its warming trend. And personally I suspect it is a little of both.
Obviously there are other variables one might consider for viewing the temporal evolution of the system. Trend in warming by latitude — showing success five year lines would be one example.
There are undoubtedly others. Perhaps you could suggest what you are going to calculate, have people make predictions as to what you will find and explain why they expect it — and then plot it?
That is, if it at all interests you — and when you feel like doing it. This is after all your baby and your precious time.
*
PS I don’t always have the time to comment. Other times I do but don’t really have anything worth contributing. And other times I think I do and start to write something — only to decide it is redundant or not as valuable as I might have thought — and decide not to submit. But I do check this blog every day — even when I am not participating for days at a stretch.
Marcus // September 15, 2009 at 6:15 pm |
So, I realize that this is the usual refrain of the skeptics, but… might the annual pattern changes you’re seeing be linked to the PDO? Eg, you see a quick change in the late 70s/early 80s, and another change back in recent years, which just happens to be the standard PDO transitions.
(and whereas I don’t believe that the PDO controls long-term temperature trends, I might be willing to believe that the PDO could affect distribution of heat _within_ a year)
Deep Climate // September 15, 2009 at 8:23 pm |
True Sceptic (and any others interested),
I originally produced the monthly trend graph as an introduction to a post analyzing the wide divergence of trends in UAH LT (which are in turn the result of a strong recent annual cycle in that data set).
That post is at:
http://deepclimate.org/2009/03/26/seasonal-divergence-in-tropospheric-temperature-trends-part-2/
Tamino posted on the UAH annual cycle a year ago, IIRC (and those posts were the impetus for my generating a “trend” view of the phenomenon).
For more on these data sets try IPCC AR4 WG1 3.4.1 pp. 265-271 (section on “free atmosphere”). You can also follow Tamino’s data links to get to the RSS and UAH websites.
Deep Climate // September 15, 2009 at 8:53 pm |
Tamino,
I knew you’d fall into my trap! Thanks for this – I was hoping you would do annual cycle analysis.
When I look at the NH GISS annual cycle, I see fair similarity from 1980-2000 and, as expected, a much different cycle from 2005 on (“autumnal bump”). The 2000-2005 cycle looks somewhere “in between”.
Looking at the 30-year trends as I did in one of my comments also seems to show a possible break point around 2002-3.
So … it might be interesting to break the NH annual cycle analysis into two parts, say 1980-2003 and 2003-2009 (or whichever year would give the largest “swing” in annual cycle).
As to what it means, it may be too early to say (not to mention requiring more knowledge than I possess). But I do have ideas for further analysis that might shed some light.
Probably it would be good to look at it zonally – to see if this “new” NH annual cycle can be mainly attributed to certain latitude bands. As I said before, I expect it to be strongest north of 60, but that’s just a hunch. At least, that might plausibly explain why it is strongest in GISS.
Timothy Chase // September 16, 2009 at 2:06 am |
Marcus wrote in part:
I believe the following may be relevant — particularly what I have bolded — which was quite novel at the time that it was proposed, but is I believe now mainstream:
At one point I had concluded in relation to this,
“One can easily argue that to a first approximation, forcing is forcing, whether it is solar or anthropogenic, and climate modes can be expected to respond to forcings in roughly the same manner regardless of the nature of those forcings.”
But there will of course be differences.
For example, if warming of the troposphere is due to solar forcing then the stratosphere will warm, summers will warm more quickly than winters and so on. In contrast, if the warming of the troposphere is due to greenhouse gas forcing then the stratosphere will cool and the winters will warm more quickly than summers.
But to a first approximation forcing is forcing, and warming due to greenhouse gases will largely have the same effects as warming due to increased solar insolation. As such, warming due to forcing by greenhouse gases should largely affect climate modes the same way as warming due to forcing by solar radiation — resulting in the same sort of regime changes with respect to climate modalities (“climate oscillations”). As such one should expect the behavior of climate modalities to reflect changes in forcings in essentially the same way and at roughly the same time as the trends in temperature.
Or so I would presume. If so, then the changes in timing of the warming could be the result of both the warming and the change in the behavior of the PDO — without the degree to which one is responsible in any way necessitating a reduction in the degree to which the other is responible.
Except in the case of identity, all causation is mediated, but some causes are more direct than others, and in this case it could be the behavior of climate modalities that acts as the more immediate cause and thereby mediates causation due to the forcing of greenhouse gases — in much the same way that the bullet may be “the cause of death,” but the pulling of the trigger may also be “the cause of death” — as viewed from within a different albeit intimately related context.
cce // September 16, 2009 at 4:27 am |
Could the post 2005 autumn “bump” be attributed to (or compounded by) the accelerated arctic ice loss of late? Isn’t autumn when the ice albedo feedback should be strongest? i.e. when ice levels are at their lowest, but before the lights go out. I thought I read that somewhere.
Gareth // September 16, 2009 at 9:34 pm |
Re Arctic influence on autumn temps. Have a read of chapter one in the WWF’s recent Arctic report (PDF) — Atmospheric circulation feedbacks, by Serreze & Stroeve. It’s a very good overview of what the latest work suggests is going on. One key finding: amplified warming in the Arctic itself spreads over the land around the ocean, and is most pronounced in autumn and winter.
Deep Climate // September 16, 2009 at 9:58 pm |
I would think albedo effects would be strongest in September, when ice is at a minimum and the largest difference between recent and past sea ice extent occurs. So if there is some sort of lag effect, maybe …
The albedo feedback effect would have to be felt at the nearest reporting stations. i.e. coastal stations that have less ice nearby than they did formerly.
BTW, as mentioned above, it appears to me that the “autumn bump” is post-2002, not 2005.
mspelto // September 16, 2009 at 10:45 pm |
Deep Climate the albedo effects are strongest in September. However, the impact of reduced sea ice extent is more important in the changes in long wave radiation fluxes. By September the role of solar radiation is diminishing. Serreze et al (2009) noted that radiant fluxes from the surface have increased in the autumn. That is the warmer open water is radiating more heat than a cooler sea ice cover would initially.
Timothy Chase // September 16, 2009 at 11:02 pm |
Deep Climate wrote:
That explains it.
With me I was thinking of the fact that winter temperature trends will be more determined by greenhouse gas reducing longwave emissions to space than moist air convection, but at arctic temperatures moist air convection will be fairly low anyway as the rate of evaporation (or sublimation, for that matter — at least above -40°C) doubles for every 10°C — and as such should be fairly negligible in the arctic.
The earlier warming would then be a function of the melt beginning earlier in the year — and even if the ocean itself isn’t showing, the ice will have darker ponds on top, or alternatively, simply turn dark as the result of increased moisture.
I should have thought of that. Just about anyone else would have been thinking in terms of albedo first, at least with respect to the arctic. Oh well.
Timothy Chase // September 16, 2009 at 11:54 pm |
Gareth wrote:
Deep Climate // September 17, 2009 at 2:49 am |
Mauri, it’s great to have you commenting here.
If there is strong warming observed in autumn at stations near the Arctic ocean, and it seems from Garth’s comment that there is, then the open water radiant flux phenomenon could plausibly explain the “autumn bump” in GISS. As I recall, GISS uses those stations to estimate Arctic Ocean warmth (via “teleconnection”). And that could also help explain why the bump is less evident in HadCRU, which doesn’t estimate Arctic Ocean temperatures, at least not up to 90N.
From the WWF summary linked to by Gareth:
That would appear to be enough to create a strong “autumn bump”, especially as that warming trend spreads to the surrounding land, as mentioned above.
And, of course, it implies that the “autumn bump” is physically realistic – scarily so.
Layman Lurker // September 17, 2009 at 3:10 am |
So your take then is that the “autumn bump” is independant of the winter “annual cycle anomaly” seen prior to 2005?
Deep Climate // September 17, 2009 at 3:15 am |
More complete quote from body WWF summary:
From the WWF report, ARCTIC CLIMATE FEEDBACKS: GLOBAL IMPLICATIONS
1. ATMOSPHERIC CIRCULATION EEDBACKS by Mark C. Serreze and Julienne Stroeve
The rest of the report is also sobering (well, depressing actually). It covers ocean circulation, sea level and carbon cycle feedbacks. If nothing else, read the executive summary.
I second Gareth’s recommendation – the link is worth repeating:
http://assets.wwf.org.nz/downloads/wwf_arctic_feedbacks_report.pdf
Deep Climate // September 17, 2009 at 4:08 am |
Layman Lurker:
My “take” ( (FWIW, which may not be very much), after reading Mauri Spelto’s comment and Gareth’s link: It’s not independent, but rather the changing seasonal pattern is evidence of a certain type of feedback coming to the fore. And it’s happening faster than previously projected by climate models.
Layman Lurker // September 17, 2009 at 5:37 am |
I think that Spelto’s comment was interesting and seems plausible in explaining a growing “autumn bump” through decreasing Sept. minimums. Could you explain how this would tie in with a “shift” from the winter “annual cycle anomaly” of the previous 25 years (itself a departure from the baseline).
jyyh // September 17, 2009 at 8:48 am |
the ‘autumn bumb’… the decomposition of plant matter happens already in autumn? might it be the spring time warming has speeded up plant life cycles so that they start to wither and decompose even though there is still enough light and warmth present? are we seeing a response from ecosystems? probably there is also some signal from the permafrost methane, since the added spring/summer warmth gets deeper in the ‘non-active layer’ as some conservationist might say.
Kevin Stanley // September 17, 2009 at 2:18 pm |
I’m pretty sure it’s Mauri (S.) Pelto rather than Mauri Spelto.
Deep Climate // September 17, 2009 at 2:56 pm |
My apologies to Mauri S. Pelto (not “Spelto”) for getting his name wrong.
Layman Lurker // September 17, 2009 at 3:10 pm |
Apologies, Dr. Pelto. I went by DC’s response to me and hadn’t clicked on your link.
Sekerob // September 17, 2009 at 3:42 pm |
Lurking the climablogs and not knowing Mauri Pelto? Shame.
Visited a few weeks ago the Maiella Cirque, about 2450 meter altitude and low and behold, late August and still a substantial patch of snow. Rather clean at the top, so it must have survived the summer freshly down from the 2009 winter and there I mused… this topples any global warming stories… a new most Southern of Europe glacier in the making ;>)
Yes, I’ve got photographic evidence. I’ll return when the first Capellino is at the top to see if it becomes second year snow.
Down below, we had a 32C real-feel day. Summer ain’t over yet. The Italian meteorology report for August was 40-87% less precipitation.
mspelto // September 17, 2009 at 3:45 pm |
The BAMS State of The Climate 2008, report has a very thorough review of the Arctic Climate for the year, including the following two quotes. I suggest it is worth a look, it cannot be done in a few minutes. The editors due an excellent job of condensing, I had to rewrite my section many times, shorter and shorter without taking out areas covered, but that means slower digestion. http://www.ncdc.noaa.gov/oa/climate/research/2008/ann/bams/full-report.pdf
“It is apparent that the heating of the ocean in areas of extreme summer sea-ice loss is directly impacting surface air temperatures over the Arctic Ocean, where surface air temperature anomalies reached an unprecedented +5°C during October through December 2008. “…”There is evidence that by creating a new major surface heat source, the recent extreme loss of summer sea-ice extent is having a direct feedback effect on the general atmospheric circulation into the winter season (Francis et al. 2009).”
Layman Lurker // September 17, 2009 at 5:25 pm |
Thank you for your response and the link Dr. Pelto. In the context of Tamino’s post, it is particularly interesting to read about how the trend of decreasing arctic sea ice likely affects frequency changes and persistence of atmospheric circulation patterns in the arctic.
GFW // September 17, 2009 at 8:33 pm |
If the autumnal bump is a result of the greater amount of open arctic water giving up heat in the fall – isn’t that a *good* thing? It would be the first significant negative feedback I’ve heard of – loss of ice in summer allowing greater loss of heat (ultimately to space) in the fall.
Layman Lurker // September 17, 2009 at 9:36 pm |
GFW, here is a description in the in the BAM report which Dr. Pelto linked to (page 98):
“The summer of 2008 ended with nearly the same extreme minimum sea-ice extent as in 2007, characterized by extensive areas of open water (see section 5d). This condition allows extra heat to be absorbed by the ocean from longwave and solar radiation throughout the summer season, which is then released back to the atmosphere the following autumn (Serreze et al. 2009).”
Layman Lurker // September 17, 2009 at 9:39 pm |
That should read “BAMS report”
Gareth // September 17, 2009 at 10:52 pm |
Timothy: If you really want to scare yourself about methane hydrates, the last chapter in the WWF report should do it. I blogged about it here.
Mauri: Thanks for the BAMS link. Tremendous overview.
Re: the “autumn bump”. It’s not a negative feedback, it’s the system responding to a change in heat flows. As the ocean cools, it gives up heat to the atmosphere, and the atmospheric circulation (weather) takes that heat and spreads it around. In so doing, it also moves a lot of water vapour, so we can expect increased snow fall around the Arctic.
The presence of the extra heat will also affect the circulation patterns around the northern hemisphere, down to the mid-latitudes. Exactly how is the interesting question… ;-)
Kevin McKinney // September 18, 2009 at 3:09 am |
Re “autumn bump”: additionally to the radiation fluxes, there’s the heat given up during freezing. (This, too, should correlate well with the reduced extent–as opposed to ice volume–as thickening of the ice subsequent to the initial freeze presumably gives up heat to the ocean, not the atmosphere.) Is this effect large enough to be part of the picture?
Timothy Chase // September 18, 2009 at 4:00 am |
Gareth wrote:
In my case more likely depress myself. Feels a bit like watching a train wreck in slow motion. But thank you for the recommendation. I will check it out. (Should just read the whole pdf but next week or two is going to be fairly hectic — including a possible stint in hospital.)
Juliette // September 18, 2009 at 8:04 am |
Very slightly off topic: we apparently got ourselves a yearly minimum sea ice extent. Expect al skeptics who usually claim the temperature records isn’t long enough to make trends to suddenly claim three years of growth means there’s a recovery.
Gareth // September 18, 2009 at 8:18 am |
Get well soon.
And extended bed rest is very good for catching up on reading…
Deech56 // September 18, 2009 at 11:10 am |
Timothy – good wishes also from this neck of the woods.
J // September 18, 2009 at 11:24 am |
Gareth writes: Timothy: If you really want to scare yourself about methane hydrates, the last chapter in the WWF report should do it
Thanks for the link. I followed the link on your blog and read that chapter of the report. You’re right, it really is disturbing.
dhogaza // September 18, 2009 at 1:37 pm |
Yes, they’ve been actively doing this all month as the slow-down made it obvious that the minimum was near.
Timothy Chase // September 18, 2009 at 5:29 pm |
Gareth wrote:
Gareth, all,
The hospital stay is more or less certain. But it will be short and very little risk. An angiogram — a very simple procedure. I’ve had two put in before. Then only a day or so or even less if they can’t put in a stint.
I am hoping for the stint, though. Angina has been making the simple act of walking up a slight incline a few blocks difficult for the past year or so. I enjoy brisk and long walks — the latter particularly while taking photographs.
But even without the stint things can improve quite considerably. My cardiologist told me the last time I saw her that over time exercise will create new, collateral blood vessels.
I remember reading how during morpheological development organisms will development less or more extensive circulatory systems, compensating for the altitude and consequent air pressure of their environment. The consequent organismal plasticity leads to greater evolvability.
Didn’t realize the same ability to develop more extensive circulatory systems applied to adults as well. Makes sense that it would I suppose.
Anyway, no worries.
Steve Bloom // September 18, 2009 at 9:38 pm |
Tamino, this recent paper finding a phase change in the seasons seems relevant to your discussion. Abstract:
“The annual cycle in the Earth’s surface temperature is extremely large—comparable in magnitude to the glacial–interglacial
cycles over most of the planet. Trends in the phase and the amplitude of the annual cycle have been observed, but the causes
and significance of these changes remain poorly understood—in part because we lack an understanding of the natural
variability. Here we show that the phase of the annual cycle of surface temperature over extratropical land shifted towards
earlier seasons by 1.7 days between 1954 and 2007; this change is highly anomalous with respect to earlier variations, which
we interpret as being indicative of the natural range. Significant changes in the amplitude of the annual cycle are also
observed between 1954 and 2007. These shifts in the annual cycles appear to be related, in part, to changes in the northern
annular mode of climate variability, although the land phase shift is significantly larger than that predicted by trends in the
northern annular mode alone. Few of the climate models presented by the Intergovernmental Panel on Climate Change
reproduce the observed decrease in amplitude and none reproduce the shift towards earlier seasons.”
[Response: You omitted the link.]
Ray Ladbury // September 18, 2009 at 10:08 pm |
Timothy,
Allow me to add my best wishes for a speedy and full recovery to the pile. Best of luck.
Deep Climate // September 19, 2009 at 3:37 am |
The link for the article abstract given by Steve Bloom.
http://www.nature.com/nature/journal/v457/n7228/abs/nature07675.html
Nature 457, 435-440 (22 January 2009) | doi:10.1038/nature07675; Received 25 April 2008; Accepted 20 November 2008
Changes in the phase of the annual cycle of surface temperature
A. R. Stine, P. Huybers & I. Y. Fung
Gavin's Pussycat // September 19, 2009 at 9:48 am |
http://www.nature.com/nature/journal/v457/n7228/abs/nature07675.html
That Huybers guy again ;-)
TCO // September 19, 2009 at 1:05 pm |
http://www.people.fas.harvard.edu/~phuybers/
He has links to a free pdf and interestingly an opinion piece by Thomson, which I really liked. It’s not “anti-AGW”. But it is anti-modeling. Lot of money. Lot of code. Lot of flux adjustments. But “basic physics” my ass. I LOVE Huybers! I loved him before any of you. He’s a real scientist. Not a DKos agitator. Not a Canadian penny stock agitator. I would buy him and Zorita drinks in a heartbeat.
Ray Ladbury // September 19, 2009 at 3:18 pm |
TCO, your antipathy toward modeling is puzzling. Certainly, the empirical evidence we have about the radiative behavior is sufficient to establish it as a greenhouse gas. We know greenhouse gasses are responsible for about 33 degrees of warming for Earth over what it would be otherwise. This, coupled with phenological and climate observations and the paleoclimate record is sufficient to establish a significant, credible risk arising from greenhouse gasses. Models play much more of a role in placing upper limits on that risk. If you don’t trust the models, I would think you should be much more concerned about the risks of climate change–at least if your position is at all evidence based.
dhogaza // September 19, 2009 at 4:25 pm |
He must hate modern science and engineering, then. From bridge building to airplanes to drug efficacy to epidemiology to population ecology, all points in between, left, right, above and below you’ll find models. Some statistical, some from first principles, but pervasive.
Models are useful. I experience this every day in the pacific northwest, where seven day forecasts are far, far more accurate than when I was young (the PNW has the reputation of being one of the most difficult places to forecast weather in the lower 48).
TCO // September 19, 2009 at 5:12 pm |
My “betting Bayesian” prior for the century effects would be similar to the general IPCC/model consensus. I just don’t think the modeling exercises add that much. They are super complicated and don’t predict eka-silicon (germanium). I think the rise in temps along with the rise in CO2…as well as the simple greenhouse intution…is powerful in creating my Bayesian prior. No offense to all the people drawing white collar salaries doing something they love and feel helps the world. But I’m darn skeptical of extremely complex models that are essentially untestable without some parallel earths.
Doesn’t mean I don’t think AGW is happening. And will continue. Just means I think this area of science is not adding insight.
Huybes on the other hand kicks ASS. Loved when he analyzed MBH and MnM. I didn’t even understand all the blather about correlation and covariance “matrices” that McI likes to put up as squid ink. (There is actually no need to even conside linear algebra…it’s just an issue of normalization factors…Huybers cleared up that McI was changing two “factors” in the method and then attributing the impact to one factor (with some slimy evasions of course).
But Huybers is a genuinely curious guy. He’s like the high school math teacher that inspires you to really track down answers…wherever they go. El Nino guy (can’t remember his name) is also. So is Atmoz, actually. Definitely Zorita too.
Now…feel free to get back to another discussion of how details don’t matter and what does is taking on Watts and Inhofe. Yawn…
Philippe Chantreau // September 19, 2009 at 5:14 pm |
As soon as you can, start walking Tim. And use stairs. Walking and going up moderate inclines are excellent exercises to build collateral circulation, so long as you do it every day for a significant amount of time (ideally one hour, best if it is in one stretch, with shorter periods throughout the day).
Best of luck
TCO // September 19, 2009 at 5:18 pm |
Basically Zorita and Huybers would each get 4 drinks. El Nino guy would get…2 maybe. Tammy would get 1. You guys…well I would only do it out of gentlemanliness if trapped in an airport TGIF…but wouldn’t cross the room to make the offer. Atmoz would get unlimited…because I have a warm spot in my heart for grad students. If we’re talking…they’re not paying for food or drinks. The professors can ante up, though. ;)
Deep Climate // September 19, 2009 at 5:40 pm |
I wrote up some comments based on the abstract of Stine et al. – and then found the whole article, thanks to TCO! So I’ll hold off for now.
The first thing I noticed is that the study is based on HadCRU only.
Here are the links:
http://www.people.fas.harvard.edu/~phuybers/Doc/seasons.pdf
http://www.people.fas.harvard.edu/~phuybers/Doc/seasons_supplementary_info.pdf
dhogaza // September 19, 2009 at 6:33 pm |
Good. That would save me the trouble of having to call security.
TCO // September 19, 2009 at 6:59 pm |
Cyber-smooches, Deep Climate.
dhogaza // September 19, 2009 at 7:00 pm |
Words like “super” complicated and “extremely” complex are meaningless. I’ve been writing programs measured in 100s of thousands of lines of code since my early twenties (and measured in 10s of thousands of lines in high school), so I’m just not impressed with your superlatives. Conceptually climate models aren’t terribly complex. The complexity is mostly in the physics being modeled, but my own exploration has led me to learn that most if not all of that is described in a series of papers. So, for instance, the cloud convection portion of NASA GISS Model E is covered by publications so you can go study it without having to laboriously work through a bunch of FORTRAN.
I remember from a previous conversation that you did a bunch of shoot-from-the-hip claims about model shortcomings that, upon investigation, turned out to be baloney.
“essentially untestable” is just false BTW,
TCO // September 19, 2009 at 7:06 pm |
Deep Climate would get a Sammie as well…
Steve Bloom // September 20, 2009 at 12:24 am |
Thanks to all for filling in the links for Stine et al. Tamino, does this affect your results?
Steve Bloom // September 20, 2009 at 12:41 am |
Briefly, TCO (since I seem to recall having made this point to you before):
It’s been widely understood for more than 20 years that the sort of CO2 levels we’re headed toward will be enough to flip us out of the late Pliocene/Pleistocene ice age and back into something like a mid-Pliocene climate (with little permanent ice and much higher sea levels as the most obvious effects). In a sane world, this information would be enough to put the brakes on hard. Rather than act, the people in charge of public policy seem to want to know with as much precision as possible the pace at which the changes will occur so they can engage in what amounts to a large-scale game of blackjack. Climate modeling is the only possible way to get a handle on this information, thus the emphasis on it. If you have any bright ideas about how else to proceed, by all means let us know.
Ray Ladbury // September 20, 2009 at 1:41 am |
TCO, allow me to introduce two concepts:
1)Too complicated for TCO to understand.
2)To complicated for even experts to understand.
My hypothesis is that the two concepts are not equivalent.
Models work when they elucidate the physics, and by this definition, climate models work.
Steve Bloom // September 20, 2009 at 2:30 am |
Speaking of climate blackjack, it’s being played in China. The lede from the second article is striking:
“Don’t expect China to keep global warming below 2C, a senior government adviser warned in Beijing today at the launch of an influential report on the nation’s prospects for low-carbon growth.”
dhogaza // September 20, 2009 at 3:48 am |
Ray’s summary is decent.
TCO, are you *really* going to make me search this site for the earlier demolishment of your anti-model claims?
Or are you going to disappear for some months, only to reappear again, causing us who have hope that you’re honest (well, actually, I don’t, I’ve known you for years), to resurrect yet again the trivial rebuttals to your ignorance?
All I’m seeing is that you’re the kind of TCO who should die in battle, rather than go round-and-round, because a good, clean, ignorant death in duty is more likely more acceptable to you than to be proven wrong.
As you have been, often.
Even though you’re smarter than all of us.
dhogaza // September 20, 2009 at 3:51 am |
“Don’t expect China to keep global warming below 2C, a senior government adviser warned in Beijing today at the launch of an influential report on the nation’s prospects for low-carbon growth.”
Umm, how would we keep global warming below 2C? I think this essentially falls into the bin that China’s not going to fall on her sword so the first world can take half-assed measures and reach a modest, painless, goal.
What would you do if you were in charge in China?
Would you say … “The first world has caused this problem, so China will devote herself to another century of poverty, death, and low life expectancy so you can continue to drive your GMC Yukon!”
I don’t think so …
Timothy Chase // September 20, 2009 at 6:46 am |
Gavin’s Pussycat wrote:
From the article:
Would I be correct in concluding that the “thermal mass” that they are referring to is that of the ice (where heat will penetrate only so far) vs that of the ocean (with its greater thermal mass), and that it is in essence the greater thermal inertia that would retard a warming atmosphere from reaching its peak temperature.
In any case, clearly a trouble maker — giving the modelers a hard time like that.
And then towards the end:
Oh dear!
Looks like he doesn’t want anyone to be happy…
Gavin's Pussycat // September 20, 2009 at 7:29 am |
TCO:
> I just don’t think the modeling exercises add that much._
That’s an optical illusion… they add robustness. Climatic sensitivity is notoriously hard to pin down, so you don’t ignore any independent approach. If very different approaches — paleo, volcanic explosions, models — give results that are close, it adds confidence that there isn’t any large structural uncertainty you have overlooked.
That being said, we are moving into territory for which there is no precise paleo analogue (though, PETM…). Modelling is all we have there.
About Huybers and MBH yeah… I read that too.
Deep Climate // September 20, 2009 at 7:30 am |
Steve Bloom wrote:
Personally, I don’t see that it does.
For one thing, HadCRU has much less of an “autumn bump” in recent years than GisTemp (presumably because HadCRU does not include estimates for the Arctic Ocean), so the phenomenon studied in this post, would not have shown up in Stine et al.
Also note that Stine et al. were studying the absolute temperature annual cycle, rather than the anomaly annual cycle, and also examined a longer period (back to the 1950s). At first glance, I don’t think the Stine et al analysis would capture the changes in shape in the absolute annual cycle that would result from changing seasonal patterns of warming.
BTW, I’m not all that convinced that the described discrepancies with model results are that significant, but I need more time with this paper to comment in any detail.
http://deepclimate.files.wordpress.com/2009/03/global-month-trends1.gif
Barton Paul Levenson // September 20, 2009 at 11:21 am |
How untestable are models?
Cribbing from earlier posts here and elsewhere…
Let’s review the successful predictions of the models. The models predicted that the globe would warm, and about how fast, and about how much. They predicted that the troposphere would warm and the stratosphere would cool. They predicted that nighttime temperatures would increase more than daytime temperatures and winter temperatures more than summer temperatures. They predicted polar amplification. They predicted that the Arctic would warm faster than the Antarctic. They predicted the magnitude (0.3 K) and duration (two years) of the cooling from the Mt. Pinatubo eruption. They made a retrodiction for Last Glacial Maximum sea surface temperatures which was inconsistent with the paleo evidence, and better paleo evidence showed the models were right. They predicted a trend significantly different and differently signed from UAH satellite temperatures, and then a bug was found in the satellite data. They predicted the amount of water vapor feedback due to ENSO, the response of southern ocean winds to the ozone hole, the expansion of the Hadley cells, the poleward movement of storm tracks, the rising of the tropopause, the rising of the effective radiating altitude, the clear sky super greenhouse effect from increased water vapor in the tropics, and the near constancy of relative humidity on global average. They predicted the expanded range of hurricanes and cyclones–a year before Katrina showed up off the coast of Brazil, something which had never happened before. Looks like a pretty good track record to me. Not “untestable” by any stretch of the imagination.
Are there problems with the models, and areas where they haven’t gotten it right yet? Sure there are. The double Inter-Tropical Convergence Zone which shows up in some coupled models, ENSO variability, insufficiently sensitive sea ice, diurnal cycles of moist convection, and the exact response of climate to clouds are all areas of ongoing research. But the models are still the best thing we have for climate prediction under different scenarios, and there is no reason at all to think they’re getting the overall picture wrong.
Ray Ladbury // September 20, 2009 at 1:33 pm |
Barton’s summary of the contributions and verification of the models is a good one. All of these confirmations support the models, though some provide more support than others. In particular, I think the strongest results are those that would be unexpected if the current warming were not greenhouse driven or which were otherwise “unexpected”. These inclde:
1)coupled stratospheric cooling and tropospheric warming
2)diurnal and seasonal effects
3)Pinatubo
4)UAH and last glacial sea surface max temp
5)water vapor feedbacks
I don’t consider the data on expanded range of tropical storms sufficiently robust to provide strong support, but it’s getting there.
In my field (radiation effects in seiconductors), the vast majority of studies still merely irradiate a microcircuit or other semiconductor part and report the anomalous behavior. We call this “squirt and tell”. I suspect TCO is a squirt-and-tell scientist if he’s a scientist at all. Unfortunately, the majority of microelectronics (and of nature) is sufficiently complex that you can’t really understand things without modeling. Of course, that presumes that your goal is understanding.
David B. Benson // September 20, 2009 at 5:44 pm |
Barton Paul Levenson // September 20, 2009 at 11:21 am — Very nice summary!
However, I don’t think Katrina was the tropical cyclone observed in the southern hemisphere. Not sure.
Deep Climate // September 20, 2009 at 8:53 pm |
I said:
Rereading this, I should have been more definitive. Since only the linear trend of the phase and amplitude of the annual cycle was analyzed, the study fails to analyze the higher frequency components of interest, let alone how these change over time.
Also there appears to be a discontinuity in the land phase lag anomalies around 1990 (see figure s6 in the SI). The significant negative linear trend for 1954-2007 would appear to be entirely due to this discontinuity.
Turning from an insufficiently deep analysis of the annual cycle, to one that looks much more promising, I’m looking forward to the completion of Tamino’s latest post:
http://tamino.wordpress.com/2009/09/19/seasonal-cycle-in-central-england-temperature/
[Response: I was looking forward to it too. But I had a nasty fall and I've injured one hand, so typing is slow and painful ... I'm not sure when I'll be able to do it.]
TrueSceptic // September 21, 2009 at 11:44 am |
Sorry to hear that. Any bones broken?
Get well soon. :)
Steve Bloom // September 20, 2009 at 9:31 pm |
dhogaza, of course the Chinese statements need to be seen as part of the posturing leading up to Copenhagen. Not enhancing the quality of life of the bulk of their population that hasn’t benefited from recent development is a complete non-starter for them, and they very likely will need outside help finding a sufficiently low-carbon pathway to keep the planet from exceeding 2C (itself a dangerously high target, but that’s another discussion). At the same time, the Chinese will be among the principal near-term victims of exceeding 2C and they (and the people they’re negotiating with) know it. What’s remarkable given recent Chinese history is the extent to which those likely near-term impacts and the implications thereof are being discussed candidly (although sometimes mixed with weird assertions such as the unsupported claim that it’s been hotter earlier in Chinese history). While on the one hand one would think that sort of talk would place them at a disadvantage in the negotiations, a climate-disrupted China would almost certainly be a politically destabilized China, and avoiding that outcome is worth s0me serious money from the U.S. and Europe. We live in interesting times, as the old curse goes.
Steve Bloom // September 20, 2009 at 9:33 pm |
Confusingly, the SH Atlantic cyclone was Caterina.
Steve Bloom // September 20, 2009 at 9:46 pm |
Thanks for all of that, DC. Maybe email Stine to ask for a comment?
Steve Bloom // September 20, 2009 at 9:47 pm |
BPL, just to note that the UAH error was in UAH (the analysis) rather than in the data.
Steve Bloom // September 20, 2009 at 9:52 pm |
I had a similar injury (wrist sprain) a couple of weeks ago, Tamino, and am still feeling your pain somewhat. Get better soon!
David B. Benson // September 20, 2009 at 10:07 pm |
Tamino — We all will be happy to wait until keying for you is no longer painful. In the nonce, no keying will, I believe, speed recovery.
We all want it to be sooner than later.
Timothy Chase // September 21, 2009 at 2:02 am |
Steve Bloom wrote:
Actually Catarina…
“Hurricane” Catarina hits Brazil
http://earthobservatory.nasa.gov/IOTD/view.php?id=4369
Cyclone Catarina
http://en.wikipedia.org/wiki/Cyclone_Catarina
Timothy Chase // September 21, 2009 at 3:24 am |
Steve Bloom wrote:
Certainly seemed that way.
I am not particularly fond of the Chinese government. I know horror stories — some fairly recent — which would probably be a distraction. I am also a former “libertarian,” although I have always tended to think of myself as a “classical liberal.” Spirit of 1776 — that sort of thing.
However, I think it is fair to say regarding the attitude of the Chinese government towards the environment it has been close to non-existent. Gavin visited where he saw “clear days” – not a cloud in the sky – with pollution rendering the sun quite invisible in some parts of the country.
Presumably the pollution may have doubled the rate of regional warming — particularly with dark carbon against the white of the Himalayas — but with the aerosols having slowed the rate of global warming.
That seems to be changing. Health problems imply costs for the Chinese economy — irrespective of the near total lack of concern the government has for individual/human rights.
See for example:
China’s industrialization and fossil fuel aerosols have undoubtedly been masking global warming for most of the world, particularly in recent years — although how much is difficult to say. But this may be beginning to change. A bit like when the United States and Western Europe imposed clean air laws during the 1970s — at the beginning of the modern era of global warming.
Timothy Chase // September 21, 2009 at 3:41 am |
PS
Just to forestall any misunderstanding…
In my view, masking global warming by means of aerosols is a bad idea. There are the health problems associated with ever increasing amounts of aerosols as they are increased to compensate for climbing levels of greenhouse gases — at least if they are tropospheric.
Regardless of whether they are tropospheric or stratospheric there will be problems with increased drought and decreased levels of ultraviolet radiation and thus photosynthesis. Aerosols will reduce the amount of solar radiation — including ultraviolet radiation — that reaches the surface. If we chose the “geo-engineering solution” of using aerosols to further mask warming due to greenhouse gases rather than controlling greenhouse gas emissions, we would be increasing the aerosol levels over time. Thus the increasing consequent droughts and reduction agricultural harvests. And then of course there is the acidification of the world’s oceans — due to rising levels of carbon dioxide.
jyyh // September 21, 2009 at 3:55 am |
Thank you for the list, BPL, there are the things to cite when the models are questioned. Get well, Tamino.
Barton Paul Levenson // September 21, 2009 at 9:30 am |
Very sorry to hear about your injury, Tamino. With your permission, I’d like to pray for healing for you.
[Response: Please do.]
Kevin McKinney // September 21, 2009 at 1:11 pm |
BPL, thanks for your excellent summary of the soi-disant “non-validated” models’ real-world performance.
The question of modeling evokes a lot of denialist distortion–as I suspect few here will be surprised to read–so your list will be very useful for me.
Hal // September 28, 2009 at 6:46 am |
Any comments on the activity at ClimateAudit?
Ray Ladbury // September 28, 2009 at 2:28 pm |
Hal: “Any comments on the activity at ClimateAudit?”
Why?
dhogaza // September 28, 2009 at 5:37 pm |
Apparently they’ve managed to break the already-shattered hockey stick [cough] again or something like that which will again prove that all climate scientists are fraudulent grant-sucking conspirators interested in nothing other than promoting One World Government and the New World Order with a crippled economy, all non-scientists living in caves without even a fire to warm them and nothing to eat but soylent green.
What did you expect, Ray?
Deech56 // September 28, 2009 at 11:58 pm |
From the abstract of Mann, et al (2008): “Recent
warmth appears anomalous for at least the past 1,300 years whether or not tree-ring data are used.” Isn’t the scientific world passing them by?
Steve Bloom // September 29, 2009 at 1:11 am |
McIntyre says he’s broken it even harder this time. Since that would mean much greater climate sensitivity, he should now go into a blind panic, insisting that all of his followers shift to an extreme low-carbon lifestyle. I’m holding my breath starting now…
Hal, CA remains as entertaining as it ever was, but its moment in the sun has passed. This sort of flopping around to try to revover some attention is to be expected.
Ray Ladbury // September 29, 2009 at 1:27 am |
Dhogaza, I’m sorry. I should have been more specific: Why should we give a flying f*** what they are doing over at Climate Fraudit?
dhogaza // September 29, 2009 at 4:01 am |
Copenhagen … you may’ve heard about it.
Though the landscape is much less friendly for denialists these days, you know that there’s going to be a “global warming fraud!” push backed by the usual (but well-funded) suspects based on McI’s recent shit.
I’m sure you understand that it hasn’t been about science for a decade plus.
At this point, it’s only about politics.
Nathan // September 29, 2009 at 4:18 am |
Another Hockey Stick…
http://www.nature.com/ngeo/journal/v2/n1/abs/ngeo390.html
I guess there are too many now for Climate Audit
Chris S. // September 29, 2009 at 5:22 pm |
Does anyone know if there’s a handy link to the full set of hockey stick papers – has anyone collated them in one place yet?
Dappled Water // September 29, 2009 at 11:32 am |
Hey, thanks for that Nathan. I’ll add it to my collection of denier rebuttals.
Dan L. // September 29, 2009 at 11:41 am |
Because CA is still a powerful tool of the denialists’ propaganda machine.
You will have noticed that public awareness of the extent of scientific consensus on climate change has been diverging from the reality of that consensus. CA is helping drive that divergence, and the effects will be seen at Copenhagen and in the U. S. Senate.
Ray Ladbury // September 29, 2009 at 12:13 pm |
Dhogaza,
Yes, I understand the politics. I just think science needs to remain above it. If McI would deign to publish, we might have something to talk about, but if an auditor only babbles on a blog, does he make any sound?
We should simply insist that policy makers ignore any “studies” that are unpublished. If McI publishes, the scientific community can proceed to rip him a brand new and fully functional bunghole. ‘Til then, it’s noise.
dhogaza // September 29, 2009 at 1:53 pm |
You mean like when Inhofe subpoenas scientists so he can accuse them of fraud on nationally broadcast committee hearings, scientists should just ignore him?
I’m afraid that’s impossible. In a very literal sense, those subpoenaed would’ve been held in contempt of Congress.
I, too, wish for a more perfect world, but I don’t expect to live long enough to see it.
Ray Ladbury // September 29, 2009 at 3:15 pm |
Dan L., I would argue that what is needed is to educate people as to what constitutes science and why publication is an essential prerequisite.
Steve Bloom // September 29, 2009 at 6:36 pm |
How much traction would McIntyre have gotten if it hadn’t been for Republican control of Congress? Not that much, I think. Beyond that, recall that he got a fair amount of play in the mainstream media (not happening this time) and some help from a few climate scientists, most prominently von Storch. It’s key that McIntyre has expanded his attack beyond MBH to cover virtually the entire field and is happy to explore any opportunity to attack the science, as a quick glance at his site makes clear. That in itself is going to help squelch media interest.
Ray Ladbury // September 29, 2009 at 10:29 pm |
Dhogaza, At this point, I’m concerned that if we devote much attention to McFraudit, we only lend it a legitimacy it can’t acheive on its own. It’s old news, really. McI has made it clear that he has no intention of playing by the rules of science.
dhogaza // September 30, 2009 at 4:47 am |
Since his motivation is political, not trying to advance science, his decision is obvious.
But the argument, at this point, is political.
McI has had his insight – time to concentrate on the political aspect, shedding all appearances of scientific rigor.
To some degree, I agree that this spells defeat for him. But since any attempt at scientific rigor was just a ways to and end for him, I’d argue that his effectiveness (as always) is simply based on sound bites for RWingnuts (of which about 39 reside in the Senate).
Hank Roberts // September 30, 2009 at 2:44 pm |
Chris S asks about
> the full set of hockey stick papers
Chris, look up “climate reconstruction” and “paleo” — people will call some of the charts “hockey stick” (personally I called a lot of them scythes, to account for the commonly noticed wiggle in the middle, but the term never caught on). But it’s just a label for some of the charts in some of the papers.
There’s no Platonic Hockey Stick of which all visible instances are mere shadows. Nobody’s trying to “prove” a “Hockey Stick” exists.
Nor is there really a “Team” on “one side” of “the debate” nor a Stocky Hick playing the other side, the referee, and the audience for the game.
That’s all Tooth Fairy stuff.
None of that is real. What’s real is the planet and its history; what’s real is the actual papers published that try to describe what we know about it.
bigcitylib // September 30, 2009 at 3:16 pm |
Nevertheless, Steve Mc’s latest has been picked up here and there (National Post in Canada). Some kind of response would seem justified.
[Response: You're entitled to your opinion. Mine is that the "boy who cried hoax" is nothing more than an ideologically-driven broken record. Appropriate response: ignore him.
If he has a point, let him publish. And I don't mean in the National Post of Canada.]
Dan L. // October 1, 2009 at 12:39 am |
Well, that’s another thing we should have been doing for decades.
Meanwhile, McI is stoking the denial furnaces to white heat again, encouraged, no doubt, by the fact that no heavyweight from the reality based climate science world can be bothered to put him in his place.
dhogaza // October 1, 2009 at 3:32 am |
Since the underlying argument is that all climate scientists involved with proxy reconstructions are engaged in fraud …
Perhaps they’re just taking time to prepare a measured response?
Perhaps waiting for McI to grow the huevos to actually submit his work for review?
Not sure. Mostly this seems likely to result in a totally unnecessary diversion from research into trash-assing bullshit.
Ray Ladbury // October 1, 2009 at 10:12 am |
Dan L. says, “Meanwhile, McI is stoking the denial furnaces to white heat again, encouraged, no doubt, by the fact that no heavyweight from the reality based climate science world can be bothered to put him in his place.”
That is because McI is not a heavyweight. A flyweight from the reality-based climate science community could flatten this one.
Basically, his argument is: “Oh, look. If we include data we know not to be representative, we turn the results to garbage.”
Basically McI has rediscovered the 2nd Law of Thermo–the relevant statement of which in this case is:
2nd Law: If you add a teaspoon of wine to a gallon of sewage, you get sewage. If you add a teaspoon of sewage to a gallon of wine, you get sewage.
This effort is weak even by Climate Fraudit standards. The hoopla in the Post-Mortem, the Tel-a-Lie (Telegraph) and the disciples of McI merely demonstrates how pathetically gullible these guys are.