The Swiss alpine region of Valais is pictured in February 2008. German researchers trying to slow melting glaciers have set up a large screen in the Swiss Alps that they hope will trap cold air over the icy mass, Johannes Gutenberg University said Thursday.
German researchers trying to slow melting glaciers have set up a large screen in the Swiss Alps that they hope will trap cold air over the icy mass, Johannes Gutenberg University said Thursday.
“We hope our installations will bring about a net cooling of the area. And if the melt is not stopped, that it is at least slowed,” the project’s leader, geography professor Hans-Joachim Fuchs, said in a statement.
The structure, 15 metres long and three metres high (49 feet by 10 feet), was raised in the middle of the Rhone glacier in Switzerland’s southwestern Valais region by 27 students from the German university.
The purpose of the screen — which sits at an altitude of 2,300 metres — is to keep cold winds over the glacier.
Already successfully tested in a laboratory, the experiment will be studied on site until August 21, according to the university, located in the German city of Mainz.
Portland is one of the “greener” cities in the USA. So it would not be surprising to see some stories blaming the current heat wave on “Global Warming” or “Climate Change”.
It will be interesting to see how they react there in the Portland media to this string of 100 plus days.
PORTLAND, Ore. – Temperatures all over Oregon are expected to shoot past 104 degrees today, making it one of the hottest days in Oregon in years.
KATU Meteorologist Rhonda Shelby said at noon that there is a chance it could get hot enough to break Portland’s all-time heat record of 107 degrees.
Foreword: I had originally planned to post a story on this, but Steven Goddard of the UK Register sends word that he has already done a comparison. It mirrors much of what I would have written. There is a clear discrepancy between the two data sources. What is unclear is the cause. Is it differing measurement and tabulation methods? Or, is it some post measurement adjustment being applied. With a 30 percent difference, it would seem that the public would have difficulty determining which dataset is the truly representative one.
UPDATE: The questions have been answered, see correction below – Anthony
Published Friday 15th August 2008 10:02 GMT – source story is here
Just a few weeks ago, predictions of Arctic ice collapse were buzzing all over the internet. Some scientists were predicting that the “North Pole may be ice-free for first time this summer”. Others predicted that the entire “polar ice cap would disappear this summer”.
The Arctic melt season is nearly done for this year. The sun is now very low above the horizon and will set for the winter at the North Pole in five weeks. And none of these dire predictions have come to pass. Yet there is, however, something odd going on with the ice data.
The National Snow and Ice Data Center (NSIDC) in Boulder, Colorado released an alarming graph on August 11, showing that Arctic ice was rapidly disappearing, back towards last year’s record minimum. Their data shows Arctic sea ice extent only 10 per cent greater than this date in 2007, and the second lowest on record. Here’s a smaller version of the graph:
The National Snow and Ice Data Center (NSIDC)’s troublesome ice graph
The problem is that this graph does not appear to be correct. Other data sources show Arctic ice having made a nice recovery this summer. NASA Marshall Space Flight Center data shows 2008 ice nearly identical to 2002, 2005 and 2006. Maps of Arctic ice extent are readily available from several sources, including the University of Illinois, which keeps a daily archive for the last 30 years. A comparison of these maps (derived from NSIDC data) below shows that Arctic ice extent was 30 per cent greater on August 11, 2008 than it was on the August 12, 2007. (2008 is a leap year, so the dates are offset by one.)
Ice at the Arctic: 2007 and 2008 snapshots
The video below highlights the differences between those two dates. As you can see, ice has grown in nearly every direction since last summer – with a large increase in the area north of Siberia. Also note that the area around the Northwest Passage (west of Greenland) has seen a significant increase in ice. Some of the islands in the Canadian Archipelago are surrounded by more ice than they were during the summer of 1980.
The 30 per cent increase was calculated by counting pixels which contain colors representing ice. This is a conservative calculation, because of the map projection used. As the ice expands away from the pole, each new pixel represents a larger area – so the net effect is that the calculated 30 per cent increase is actually on the low side.
So how did NSIDC calculate a 10 per cent increase over 2007? Their graph appears to disagree with the maps by a factor of three (10 per cent vs. 30 per cent) – hardly a trivial discrepancy.
What melts the Arctic?
The Arctic did not experience the meltdowns forecast by NSIDC and the Norwegian Polar Year Secretariat. It didn’t even come close. Additionally, some current graphs and press releases from NSIDC seem less than conservative. There appears to be a consistent pattern of overstatement related to Arctic ice loss.
We know that Arctic summer ice extent is largely determined by variable oceanic and atmospheric currents such as the Arctic Oscillation. NASA claimed last summer that “not all the large changes seen in Arctic climate in recent years are a result of long-term trends associated with global warming”. The media tendency to knee-jerkingly blame everything on “global warming” makes for an easy story – but it is not based on solid science. ®
Bootnote
And what of the Antarctic? Down south, ice extent is well ahead of the recent average. Why isn’t NSIDC making similarly high-profile press releases about the increase in Antarctic ice over the last 30 years?
The author, Steven Goddard, is not affiliated directly or indirectly with any energy industry, nor does he have any current affiliation with any university.
NOTE OF CORRECTION FROM STEVEN GODDARD:
The senior editor at the Register has added a footnote to the article with
excerpts from Dr. Meier’s letter, and a short explanation of why my analysis
was incorrect.
To expound further – after a lot of examination of UIUC maps, I discovered
that while their 2008 maps appear golden, their 2007 maps do not agree well
with either NSIDC maps or NASA satellite imagery. NSIDC does not archive
their maps, but I found one map from August 19, 2007. I overlaid the NSIDC
map on top of the UIUC map from the same date. As you can see below, the
NSIDC ice map (white) shows considerably greater extent than the UIUC maps
(colors.) The UIUC ice sits back much further from the Canadian coast than
does the NSIDC ice. The land lines up perfectly between the maps, so it
appears possible that the UIUC ice is mapped using a different projection
than their land projection.
Click for larger image
Because the 2007 UIUC maps show less area, the increase in 2008 appears
greater. This is the crux of the problem. I am convinced that the NSIDC
data is correct and that my analysis is flawed. The technique is
theoretically correct, but the output is never better than the raw data.
Prior to writing the article, I had done quite a bit of comparison of UIUC
vs. NSIDC vs. NASA for this year. The hole in my methodology was not
performing the same analysis for last year. (The fact that NSIDC doesn’t
archive their maps of course contributed to the difficulty of that
exercise.)
My apologies to Dr. Meiers and Dr. Serreze, and NSIDC. Their analysis,
graphs and conclusions were all absolutely correct. Arctic ice is indeed
melting nearly as fast as last year, and this is indeed troubling.
Overall long term trend remains positive in lower troposphere.
Most often on this forum we have looked at either surface temperature data from surface observations or lower tropospheric temperature data derived from satellite sounders. Today I’d like to point out a short scale trend in global radiosonde data showing cooling in the last year, as well as examine the record back to 1958.
The HadAT2 dataset from the Hadley Climate Center takes in balloon radiosonde measurements taken twice daily from hundreds of points around the globe and compiles it. Here is how they describe it:
HadAT consists of temperature anomaly timeseries on 9 standard reporting pressure levels (850hPa to 30hPa). The data is also available as equivalent measures to the broad MSU satellite weighting functions. The gridded product is derived from 676 individual radiosonde stations with long-term records. Because of the criteria of data longevity the resulting dataset is limited to land areas and primarily Northern Hemisphere locations. Radiosondes are single launch instruments and there have been many changes in instruments and observing practices with time. HadAT has used a neighbour-based approach to attempt to adjust for these effects and produce a homogeneous product suitable for climate applications.
They also go on to add a cautionary note about data uncertainty:
It is important to note that significant uncertainty exists in radiosonde datasets reflecting the large number of choices available to researchers in their construction and the many heterogeneities in the data.
And they go on to suggest alternate data sets for “robustness”. For now, we’ll just stick to HadAT2, but if readers want to do comparisons against the other datasets I’ll post results here. Just visit the HadAT2 page for links.
Here is the plot of all the pressure altitude levels of temperature data since 1958:
Click for a larger image
The source data set in ASCII text is available here
In the graph above, the warmer (redder) colors represent lower tropospheric data closer to the surface (850mb for example) while the cooler blues (cyans) are the high altitude data (100, 50, and 30mb). You can see in the 850mb data, the familiar signature of the 1998 Super El Nino that raised temperatures globally.
You can also see the slow upward trend in temperature in the lower troposphere data since 1958, about 0.6°C.
To give laymen readers an idea of the vertical scope of the plot above, here is a graphic showing pressure versus atmospheric altitude. Read the rest of this entry »
The National Snow and Ice Data Center (NSIDC)’s troublesome ice graph
Ice at the Arctic: 2007 and 2008 snapshots
Overall long term trend remains positive in lower troposphere.
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