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Hilarious claim: “we know when global (cough, cough) warming first appeared in the temperature record, er, models”

From the UNIVERSITY OF NEW SOUTH WALES (via Eurekalert) and the “Where’s Waldo?” department comes this hilarious claim. Why hilarious? Because the headline says “global warming”, yet the research says that warming appeared in different decades in different parts of the world. So much for the “global” part. But, it gets better, the money quote says the USA isn’t conforming to the expected warming signal, but, “…according to the models but it is expected they will appear in the next decade.”

And then there’s this:

Nevertheless, according to model evidence, both hot and cold extremes have already emerged across many areas.

I have to wonder, do these people even read their own press releases and apply a sanity check? Given that UNSW is the source of the Dr. Chris Turney “ship of fools” fiasco, probably not.

Researchers reveal when global warming first appeared
When global warming became clearly evident in the temperature record

Median time of anthropogenic emergence and zonally averaged signal and noise for climate means and extremes are shown. Maps of median TAE averaged across 23 model simulations for (a) and (b) mean surface air temperature, (c) and (d) highest daily maximum temperature, (e) and (f) lowest daily minimum temperature, (g) and (h) total precipitation, and (i), (j) maximum 1-d precipitation for (a), (c), (e), (g) and (i) June-August and (b), (d), (f), (h) and (j) December-February. Zonally averaged values of signal (red) and noise (black) are shown where signal is the mean difference in the variable between 1989-2039 and 1860-1910, and noise is the standard deviation of the variable for 1860-1910.

The indications of climate change are all around us today but now researchers have revealed for the first time when and where the first clear signs of global warming appeared in the temperature record and where those signals are likely to be clearly seen in extreme rainfall events in the near future.

The new research published in Environmental Research Letters gives an insight into the global impacts that have already been felt, even at this very early stage, and where those impacts are likely to intensify in the coming years.

“We examined average and extreme temperatures because they were always projected to be the measure that is most sensitive to global warming,” said lead author from the ARC Centre of Excellence for Climate System Science, Dr Andrew King.

“Remarkably our research shows that you could already see clear signs of global warming in the tropics by the 1960s but in parts of Australia, South East Asia and Africa it was visible as early as the 1940s.”

The reason the first changes in average temperature and temperature extremes appeared in the tropics was because those regions generally experienced a much narrower range of temperatures. This meant smaller shifts in the temperature record due to global warming were more easily seen.

The first signal to appear in the tropics was the change in average temperatures. Later extreme temperature events showed a global warming signal.

Closer to the poles the emergence of climate change in the temperature record appeared later but by the period 1980-2000 the temperature record in most regions of the world were showing clear global warming signals.

One of the few exceptions to this clear global warming signal was found in large parts of the continental United States, particularly on the Eastern coast and up through the central states. These regions have yet to manifest obvious warming signals according to the models but it is expected they will appear in the next decade.

While temperature records generally showed pronounced indications of global warming, heavy rainfall events have yet to make their mark. The models showed a general increase in extreme rainfall but the global warming signal was not strong enough yet to rise above the expected natural variation.

“We expect the first heavy precipitation events with a clear global warming signal will appear during winters in Russia, Canada and northern Europe over the next 10-30 years,” said co-author Dr Ed Hawkins from the National Centre for Atmospheric Science at the University of Reading, UK.

“This is likely to bring pronounced precipitation events on top of the already existing trend towards increasingly wet winters in these regions.”

Importantly, the findings closely correspond to observational datasets used by the IPCC (Chapter 10 – Detection and Attribution of Climate Change) in its most recent report, which showed increasing temperatures caused by global warming.

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Here is the abstract, yes that’s right, the title says the entire thing is a simulation, something not quite so clear from their press release where they say things like:

“…now researchers have revealed for the first time when and where the first clear signs of global warming appeared in the temperature record…”

Uh, no. Model output is not the actual temperature record.

The timing of anthropogenic emergence in simulated climate extremes
Andrew D King, Markus G Donat, Erich M Fischer, Ed Hawkins, Lisa V Alexander, David J Karoly,Andrea J Dittus, Sophie C Lewis, and Sarah E Perkins

Abstract
Determining the time of emergence of climates altered from their natural state by anthropogenic influences can help inform the development of adaptation and mitigation strategies to climate change. Previous studies have examined the time of emergence of climate averages. However, at the global scale, the emergence of changes in extreme events, which have the greatest societal impacts, has not been investigated before. Based on state-of-the-art climate models, we show that temperature extremes generally emerge slightly later from their quasi-natural climate state than seasonal means,
due to greater variability in extremes. Nevertheless, according to model evidence, both hot and cold extremes have already emerged across many areas. Remarkably, even precipitation extremes that have very large variability are projected to emerge in the coming decades in Northern Hemisphere winters associated with a wettening trend. Based on our findings we expect local temperature and precipitation extremes to already differ significantly from their previous quasi-natural state at many locations or to
do so in the near future. Our findings have implications for climate impacts and detection and attribution studies assessing observed changes in regional climate extremes by showing whether they will likely find a fingerprint of anthropogenic climate change.

Source: http://iopscience.iop.org/article/10.1088/1748-9326/10/9/094015/meta

The paper is open source, should you want to bother reading it. http://iopscience.iop.org/article/10.1088/1748-9326/10/9/094015/pdf

Note: this story was edited shortly after publication to remove a duplicated word, “the”.

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