Tag Archives: Temperature record

What is global temperature?

When I write here about climate change you can be sure one or more trolls will pop up and tell me about the snow in the UK. Or accuse scientists of relying on this year’s New Zealand drought in their claims of climate change. It seems surprising that no matter how many times we point out the climate is not the same as weather, and global climate change is not the same as local or regional weather, some people seem to think such arguments are valid.

I have illustrated the difference before here – but here’s another example I picked up from Real Climate (see Response by Marcott et al.). The illustration is in response to the question of what is meant by global Temperature. Here’s what they say:

“Global average surface temperature is perhaps the single most representative measure of a planet’s climate since it reflects how much heat is at the planet’s surface. Local temperature changes can differ markedly from the global average. One reason for this is that heat moves around with the winds and ocean currents, warming one region while cooling another, but these regional effects might not cause a significant change in the global average temperature. A second reason is that local feedbacks, such as changes in snow or vegetation cover that affect how a region reflects or absorbs sunlight, can cause large local temperature changes that are not mirrored in the global average. We therefore cannot rely on any single location as being representative of global temperature change. This is why our study includes data from around the world.

We can illustrate this concept with temperature anomaly data based on instrumental records for the past 130 years from the National Climatic Data Center (http://www.ncdc.noaa.gov/cmb-faq/anomalies.php#anomalies). Over this time interval, an increase in the global average temperature is documented by thermometer records, rising sea levels, retreating glaciers, and increasing ocean heat content, among other indicators. Yet if we plot temperature anomaly data since 1880 at the same locations as the 73 sites used in our paleotemperature study, we see that the data are scattered and the trend is unclear. When these same 73 historical temperature records are averaged together, we see a clear warming signal that is very similar to the global average documented from many more sites (Figure 1). Averaging reduces local noise and provides a clearer perspective on global climate.”

ProxySites_vs_Global1-1024x907

Temperature anomaly data (thin colored lines) at the same locations as the 73 paleotemperature records used in Marcott et al. (2013), the average of these 73 temperature anomaly series (bold black line), and the global average temperature from the National Climatic Data Center blended land and ocean dataset (bold red line) (data from Smith et al., 2008).

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Climate change denier’s false “deep distress” fools no-one

Recently I commented on the High Court rejection of the climate change deniers/contrarians/sceptics arguments against NIWA’s New Zealand temperature record. I said that those attacking NIWA were “getting all falsely indignant because others have pointed out that in effect they were charging that NIWA had acted fraudulently and this had been rejected (see “Leading climate scientists” make false allegation).”

I argued that, in fact, these groups have for several years have accused NIWA scientists of fraud, even if the specific F word had not been used. It is disingenuous of these people to now claim “We never said it was fraud” and limit themselves to the literal words used in the High Court submissions.

The writer of that blog post, the well-known local climate change denier Richard Treadgold, indignantly claimed:

“the Trust did not claim fraud in its Statement of Claim to the High Court, which nowhere uses any derivative of the word fraud. The Coalition never accused NIWA of fraud.”

Come on Richard – enough of the porkies. You are just relying on reader’s ignorance of the statement. (While at the same time avoiding the long history of aggressive accusations of scientific fraud your organisations have made against NIWA scientists).

Someone from NIWA who participated in the High Court case, and therefore is familiar with the statements, sent me these comments:

“here are some accusations in the NZCSET’s statements of claim:

Paragraph 20 in NZCSET’s First Statement of Claim (July 2010), repeated in First Amended Statement of Claim (July 2011):

20.  In making the 1999 decision NIWA was influenced by the expectation that significant NZTR warming would encourage funding for additional climate change research.

If this isn’t accusing us of fraud, I don’t know what is.

Also, from NZCSET’s First Amended Statement of Claim (July 2011):

45. Given the differences in data and calculations utilised by NIWA in producing the 7SS and the NZT7 there is no known scientific basis upon which it could have arrived at the coincidence between the results of the two series. The defendant must therefore have been affected by bias or actuated by some ulterior and/or irrelevant purpose, including:

(a) The advantages of finding a warming trend broadly consistent with the advice on climate matters that NIWA has been offering to judicial, administrative and

legislative bodies during the past decade;

(b) The avoidance of political embarrassment, or reduction in public confidence in NIWA’s scientific advice on climate matters, which might arise if the NZT7 failed to align with the warming trend shown in the 7SS.

Again, this is surely accusing us of fraud, by any other name. The explicit use of the ‘F’ word is not necessary.

Treadgold pretends “deep distress” at Dr Renwick’s comment referring to “the claim by the New Zealand Climate Science Education Trust (CSET, a small group of climate change “sceptics”) that NIWA had acted fraudulently in putting together its ‘7-station’ temperature series.” Treadgold goes as far as to pretend “to those devoted to the even-handed, practical pursuit of truth this accusation is deeply distressing.” (sic). And he calls for Dr Renwick to “man up and admit their mistake, apologise and withdraw the press statement.”

What hypocrisy!

Given the long history of the unfounded attacks by Treadgold and his mates on NIWA’s scientists, that again and again their claims have been exposed as unfounded and NIWA’s position vindicated, and now finally the rejection of these denier claims by the High Court, let me repeat my suggest from 2 years ago in Painted into a corner?

Isn’t it long past the time that Treadgold and his mates “man up”, apologise and withdraw their claims?

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