Tag Archives: Temperature

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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Is your region warming?

New Scientist has produced a little tool which enables you to access regional temperature data illustrating how the world has warmed. Just enter your city and you get an indication of current temperature change from the 1951-1980 average. Together with a plot of that difference over time.

Go to Climate Change or click on the image below to check out your city.

Wellington

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Australia’s “New Normal?”

Sometimes the local climate change deniers/sceptics/contrarians behave as if they aren’t on the same planet as the rest of us. Well, perhaps that’s a bit extreme – but they do sometimes seem to at least be in a different hemisphere. While we are currently sweltering in New Zealand, and Australia is burning, they are scanning Northern Hemisphere newspapers trying to find headlines about local snow, record low temperatures, etc!

For  a while there they did start to discuss the Tasmanian fires – but what do you know? Temperatures were ignored – instead they were blaming the fires on the Australian Green Party (see Greens win, so Tasmania burns)! (Rather supports the idea that climate change denial is motivated by right wing politics).

Of course it’s easy to pontificate on local weather and temperature records (high and low) and cherry pick data to suite one’s prejudices. But as the New York Times recently pointed out the effect of climate change has been to increase the frequency of extreme weather and temperature, rather than cause specific examples (see Heat, Flood or Icy Cold, Extreme Weather Rages Worldwide).

Anyway, just to underline the local extremes here’s a climate change infographic produced by the GetUp Action for Australia Campaign. (see GetUp! – Our New Normal).

BASXeekCIAAbMw1

Click on image to enlarge

Another local climate change denial meme

I commented in Painted into a corner? that the release of NIWA’s report of the recalculation of New Zealand’s 7-station  long term  temperature series had called the local climate change deniers’ bluff. It was time for them to apologise, withdraw their slanderous attacks on NIWA and move on.

Yeah, right! That may have been the sensible thing to do, but of course they are in it for the politics, not the science. So the attacks continue.

Gareth at Hot Topic has an excellent summary of the action (see A Christmas cracker for the cranks). And of course the denier trolls have descended on his post with quite hilarious arguments. One is their claim “this new series shows no warming has occurred here since about 1960.”

Well, of course the series shows nothing of the sort. They appear to basing this incorrect claim on a paragraph in the report which says:

“The unusually steep warming in the 1940-1960 period is paralleled by an unusually large increase in northerly [air] flow during this same period. On a longer timeframe, there has been a trend towards less northerly flow (more southerly) since about 1960. However, New Zealand temperatures have continued to increase over this time, albeit at a reduced rate compared with earlier in the 20th century. This is consistent with a warming of the whole region of the southwest Pacific within which New Zealand is situated.”

Never the less these trolls and their public spokespersons, Richard Treadgold and Brian Leyland are working hardto push this meme. And they claim support from their “eyeball” analysis of the graph in NIWA’s report.

But all the data is available (Seven station data and 11 station data) and anyone can do their own analysis to check these claims.

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Climate change deniers live in glass buildings

There seems to be a big mobilisation of climate change deniers at the moment. Someone on Twitter described selective use of stolen emails, “Climategate”, as pre-Copenhagen smears. They added a quote from Churchill which I think is very apt: “A lie is halfway round the world before the truth can get its pants on.”

Most of the local media seems to be taking a relatively balanced approach to the Climategate email issue (see for example A climate scandal, or is it just hot air?). However, we now have  a “controversy” manufactured by the local Climate Science Coalition an Climate Conversation Group. A group of climate change deniers, none of them climate scientists themselves, who attempt to cast doubt on the science produced by real climate scientists. This started with a press release (Are we feeling warmer yet?). picked up and promoted by Ian Wishart (a local conspiracy theorist and climate change denier) and some local conservative and religious apologist blogs (see for example I confess I now believe in manmade Global Warming, Climate scientists caught lying and New Zealand not warming?).

Basically, it was a manipulation of raw data from NZ weather stations to support their preconceived claim of no temperature change over time. Accompanied by a claim that NIWA has dishonestly adjusted the same data to produce a temperature change.

The issues, and the scientific facts, are well covered by Garth at Hot Topic (NZ sceptics lie about temp records, try to smear top scientist) and items at the NIWA web site. I recommend reading these.

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The entropy fib

The local Christian apologetics blog “Thinking Matters” appears to have made a policy decision to outsource most of the content. Specifically to the subcontinent (where else do New Zealanders outsource to) and a Walter Mitty type of character, Johnson Philip.

Philip claims to be “a physicist, with expertise inter alia in Quantum-nuclear Physics, and has worked extensively on the inner quark-structure of Protons and Neutrons.” However, as he doesn’t appear to have published anything in a scientifc journal I think the more relevant part of his CV is that he “has also specialized in Christian Apologetics, Biblical Archeology, Journalism, Alternative Medicines, and several other fields.” He has written extensively in those areas.

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