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A Truly Climategate Pathetic Paper

2011/11/22 8 comments

<3373> Bradley:

I’m sure you agree–the Mann/Jones GRL paper was truly pathetic and should never have been published. I don’t want to be associated with that 2000 year “reconstruction”.

And here it is: “Global surface temperatures over the past two millennia” aka “Mann, M. E., and P. D. Jones, Global surface temperatures over the past two millennia, Geophys. Res. Lett., 30(15), 1820, doi:10.1029/2003GL017814, 2003.”

We present reconstructions of Northern and Southern Hemisphere mean surface temperature over the past two millennia based on high-resolution ‘proxy’ temperature data which retain millennial-scale variability. These reconstructions indicate that late 20th century warmth is unprecedented for at least roughly the past two millennia for the Northern Hemisphere. Conclusions for the Southern Hemisphere and global mean temperature are limited by the sparseness of available proxy data in the Southern Hemisphere at present.

[…]

Reconstructions of hemispheric mean temperatures over roughly the past two millennia employing proxy surface temperature data networks with sufficient spatial and seasonal sampling, temporal resolution, and retention of millennial-scale variance, support previous conclusions with regard to the anomalous nature of late 20th century temperature at least about two millennia back in time for the Northern Hemisphere. To the extent that a ‘Medieval’ interval of moderately warmer conditions can be defined from about AD 800– 1400, any hemispheric warmth during that interval is dwarfed in magnitude by late 20th century warmth. The sparseness of the available proxy data in the Southern Hemisphere lead to less definitive conclusions for the SH or global mean temperature at present.

QED.

Pielke Jr is wrong

2011/11/02 2 comments

One can slice and dice trends at will about the latest RC silliness…it doesn’t matter. Radiative effects are negligible in the troposphere, and heat waves are a matter of weather, not statistics.

 Take for example the recent mild UK weather. OF COURSE CO2 has nothing to do with it. Temperatures are higher than normal because southerlies bring warm air over from France. A proper analysis of October/November trends (and we did have quite a few very cold days already) would have to include a research on wind patterns.

Anything that doesn’t, it’s pseudoscience.

Socrates, Or Pointing The Way For The Future Of Climate Science

2011/10/27 1 comment

Roger Pielke Jr laments the withering of climatology:

Climate science — or at least some parts of it — seems to have devolved into an effort to generate media coverage and talking points for blogs, at the expense of actually adding to our scientific knowledge of the climate system

Actually, it was December 2009 when I wrote in the pages of the Spectator (UK):

This might be the most important lesson of the 1974 report on global cooling: that we need to grow up, separate climatology from fear, and recognise — much as it pains politicians and scientists — that our understanding of how climate changes remains in its infancy.

Here we are, almost two years later. For example, what do we understand about the past? Willis Eschenbach at WUWT shows it in the non-smoothed BEST reconstruction graph:

"BEST global surface temperature estimates. Gray bars show what BEST says are the 95% confidence intervals (95%CI) for each datapoint"

And what do we understand about the future? Patrick Frank in Skeptic.com’s Reading Room:

"The Special Report on Emission Scenarios (SRES-SPM-5) A2 projection from Figure 1 showing the physical uncertainty of the projected temperature trend when including ±10.1% cloud error (light shading), or the uncertainty in greenhouse gas forcing (dark shading). Inset: A close-up view of the first 20 years of the A2 projection and the uncertainty limits."

In other words: for the past, all we know for sure it’s that the error bars cover from -5C to +3C if we go back to 200 years ago. For the past, all we can estimate for sure it’s that error bars cover an enormous span if we move forward 100 years (even removing cloud uncertainty, still the 2100 error goes from -10C to +16C).

For all we know, Romans were conquering a world that was 50C colder than today, and oceans will boil before the XXII century. Or vice-versa.

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Please do not start speculating about uncertainty as a reason for doing nothing – it isn’t.

Think of science instead: what’s the way out of this cul-de-sac made up of giant error bars? How can our understanding finally leave its infancy? The way out has actually being indicated already, by a guy born in 469BC:

Socrates was wise in that he knew the he knew nothing, whereas others were unaware of their own ignorance.

If and when such a realization will become widespread, only then climate science will be able to mature away from silly manipulations, towards the approach so nicely described by Professor Sir Bernard Lovell to David Whitehouse:

One evening we unrolled the pen recorder data in a long ribbon down the corridor outside the main observing room. “Now,” he said, “look at the data. Get to know it.” His point was that before us was what the universe was saying, and that it was more important than any theory.” Data is never inconvenient. It beats theory every time.

An unexamined climate is not worth studying…

B.E.S.T. Not Yet

2011/10/21 1 comment

Plenty of brouhaha everywhere about the pre-pre-pre B.E.S.T. papers. Ignorant reactions undoubtedly already abound.

I surmise that the four pre-pre-pre-papers will get torn to pieces in the next few days (here’s my biting off the UHI article, followed by Steven Mosher’s). The quality of the BEST work will be measurable in the way they will react to that ( (a) making the necessary adjustments, (b) ignoring the lot, or (c) circling the wagons).

The jury is still much out. In the case of Anthony Watts, so far it’s been a strong (b). Assuming B.E.S.T. is not a collection of unprofessionals, such a reaction makes little sense.

OTOH we do not even know if B.E.S.T. is really about science, or something else. As I commented at Judith Curry’s blog:

Read what you write Judith! A PR strategy! Did Bohr have a PR strategy, or Maxwell, or Dirac.

The BEST PR strategy is not the best PR strategy because it became so important as to become visible. It’s THE news, as you can read at WUWT. And a total failure: science takes once again the back seat, and who cares if BEST does it for visibility rather than politics?

Your results and your work have just been buried by your team. Congratulations! /sarc

No placebo pill will ever work if it’s got “PLACEBO” written on it: likewise, no PR strategy will work if it’s so much in-your-face to its potential audience.

General Circulation Models – Another Failure (by a factor of 10, possibly 100)

2011/09/30 1 comment

UPDATE: I guess it’s GENERAL CIRCULATION Models (not “Global Climate Models”) and never again will I trust a journalist (when did I say that already… 😉 ) –

From MarsDaily (links added by me):

New analysis of data sent back by the SPICAM spectrometer on board ESA’s Mars Express spacecraft has revealed for the first time that the planet’s atmosphere is supersaturated with water vapour.

[…] descriptions of the vertical distribution of water vapour – a key factor in the study of Mars’ hydrological cycle – has generally been based upon global climate models. This gap in the data has now been addressed by the SPICAM (Spectroscopy for Investigation of Characteristics of the Atmosphere of Mars) imaging spectrometer on Mars Express.

[…] Surprising new results [published in this week’s Science], based on SPICAM data obtained during the northern spring and summer, indicate that the vertical distribution of water vapour in the Martian atmosphere is very different from previous assumptions.

[…] Until now, it was generally assumed that such supersaturation cannot exist in the cold Martian atmosphere: any water vapour in excess of saturation was expected to be converted immediately into ice. However, the SPICAM data have revealed that supersaturation occurs frequently in the middle atmosphere – at altitudes of up to 50 km above the surface – during the aphelion season, the period when Mars is near its farthest point from the Sun.

Extremely high levels of supersaturation were found on Mars, up to 10 times greater than those found on Earth. Clearly, there is much more water vapour in the upper Martian atmosphere than anyone ever imagined. It seems that previous models have greatly underestimated the quantities of water vapour at heights of 20-50 km, with as much as 10 to 100 times more water than expected at this altitude. […]

Times Atlas: Suicide By Wikipedia? – UPDATED

2011/09/20 22 comments

UPDATED: Sort of a confirmation for the below as Hanlon at the Daily Mail has posted an article where HarperCollins, the publishers of the Times Atlas Greenland fiasco, try to argue that they only depicted white the areas with ice>500m thick.

Strange things are always afoot, in matters of climate.

Incredibly, and despite having been shown the wrongness of their ways from multiple and even warmist sources, a spokesperson from the £150-a-piece Times Comprehensive Atlas of the World still maintains their debunked “AtlasGate” Greenland map is correct:

“But a spokeswoman for Times Atlas defended the 15% figure and the new map. “We are the best there is. We are confident of the data we have used and of the cartography. We use data supplied by the US Snow and Ice Data Centre (NSIDC) in Boulder, Colorado.

As the story unfolds, I would like to point to something about the new map that is strange indeed: the level of detail. See for example this comparison from Real Science:

There are two possible interpretations for that: either some people at the Times Atlas have decided to reinvent the world adding fantasy features to a previously fully white map; or, much more likely, they have used some other, existing map of Greenland, embellishing to conform to the Times Atlas style.

In fact, and intriguingly, and twice embarrassingly, there exists one map that strongly resembles the Times Atlas’ “15%” Greenland (see also the Greenland Physical Map from TourTeam.dk). And the embarrassing bits are: it’s one map used on Wikipedia. Worse, it’s supposed to be only showing ice sheet thickness, not “cover” as claimed (it doesn’t highlight the areas where the ice is less than 10m/30ft thick).

Look for example at the outline of Eastern sides of Kong Christian IX Land and Kong Christian X Land, the nearest to Iceland (brown on the Times Atlas to the left, green on Wikipedia to the right).

Look now at the Times Atlas’ Greenland map of 1999 (below, to the left) and the fact that their 2011 map (center) is so much alike the Wikipedia Greenland ice-sheet thickness (right) becomes even more evident.

So the following series of events is consistent with the observations:

  1. Times Atlas personnel read or listen from somewhere that the Greenland ice sheet is melting
  2. They open the Wikipedia page on the Greenland ice sheet
  3. As if by magic…that page contains a map of Greenland
  4. Times Atlas personnel convert that map to the Times Atlas high-quality standard

Now where’s the evidence for it? Where is it indeed, as Michael Corleone would have asked.

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This doesn’t look like a good way to enhance the reputation of a publication like the Times Atlas. As usual, it’s the stubborness of their response the real problem, perhaps even more than the original error. One is left wondering how many more mistakes have been made (perhaps them too, miraculously similar to maps posted on Wikipedia), mistakes simply too small to immediately notice. And the publishers and editor will never admit one anyway.

Global Warming Statistics 101

2011/06/18 4 comments

Averages can only tell you so much, and that’s quite little. As “global warming” is based on worldwide averages, it should be then always looked at judiciously and with a good deal of curiosity to figure out what is happening above and beyond the simple figure that is an average temperature.

Say, one lives in Placeville, a town where it’s -20C in January, +20C in July. Average is zero C (32F).

Imagine now, winters warm by 10C, summers cool by 5C. So it’s -10C in January, +15C in July. Average is 2.5C (36.5F).

Headline news: “Placeville heavily hit by global warming, average temperatures up by 2.5C“. When the real-life news is, it’s much cooler than before: still very cold in January, and now not even warm in July.

This is such a simple concept, I am always amazed how many people don’t get it. But then few grasp the most elemental aspects of statistics. And I wish three people in the world understood what “global warming” might be about.

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