February’s global temperature spike is a wake-up call

This is the largest warm anomaly of any month since records began in 1880.

This article, by Steve Sherwood, of UNSW Australia and Stefan Rahmstorf, of the Potsdam Institute for Climate Impact Research, currently working in Australia, first appeared at The Conversation.

Global temperatures for February showed a disturbing and unprecedented upward spike. It was 1.35℃ warmer than the average February during the usual baseline period of 1951-1980, according to NASA data.

This is the largest warm anomaly of any month since records began in 1880. It far exceeds the records set in 2014 and again in 2015 (the first year when the 1℃ mark was breached).

In the same month, Arctic sea ice cover reached its lowest February value ever recorded. And last year carbon dioxide concentration in our atmosphere increased by more than 3 parts per million, another record.

What is going on? Are we facing a climate emergency?
Continue reading “February’s global temperature spike is a wake-up call”

Still warming after all these years (again)

Spread this excellent new video from the talented team at Skeptical Science far and wide. It explains why the latest denialist trope — no warming for 16 years — is rubbish. Take out the impact of the three biggest factors driving natural variations in the global average temperature — volcanoes, the El Niño Southern Oscillation and the solar cycle — and what’s left is the underlying upwards trend being driven by our CO2 emissions. The world’s warming, Australia’s burning, ice is melting and we did it. No room left for wishful thinking or complacency.

Hansen: it can be cold in a warming world.

“If it’s that warm, how come it’s so darned cold?” is the heading James Hansen has given to a recently finalised essay circulated to his email list. In more sober terms he subtitles it Regional Cold Anomalies within Near-Record Global Temperature

The essay explains how the NASA Goddard Institute for Space Studies (GISS) goes about analyzing global temperature change, using electronic receipt of data from three sources: (1) weather data for several thousand meteorological stations, (2) satellite observations of sea surface temperature, and (3) Antarctic research station measurements. And for those who might suggest that there’s secret manipulation going on Hansen makes it clear that the data is available for others who want to use it:


“Although the three input data streams that we use are publicly available from the organizations that produce them, we began preserving the complete input data sets each month in April 2008. These data sets, which cover the full period of our analysis, 1880-present, are available to parties interested in performing their own analysis or checking our analysis. The computer program used in our analysis can be downloaded from the GISS web site.”

The results are that 2009 tied (with 1998, 2002, 2003, 2006 and 2007 – differences too close to matter) as the second warmest year in the 130 years of global instrumental temperature record.  The warmest was 2005.  Hansen discusses the variance of the GISS figures with the Hadley Centre (HadCRUT) which has 1998 as the warmest year, and which has been used so frequently to support claims that the globe since 1998 is now cooling. After careful comparison he concludes that the differences that have developed between the GISS and HadCRUT global temperatures are due primarily to the extension of the GISS analysis into regions that are excluded from the HadCRUT analysis. He expresses a reasonable degree of confidence in the GISS preference for 2005. Over the decade the conclusion is easier: the world has become warmer, not cooler.

What about that cold 2009 December?  There was an unusual exchange of polar and mid-latitude air in the northern hemisphere, related to the most extreme Arctic Oscillation since the 1970s. His conclusion is that December 2009 was a highly anomalous month. High pressure in the polar region can be described as the “cause” of the extreme weather. There is no apparent basis for expecting frequent repeat occurrences of December 2009 conditions, though high winter variability including cold snaps will surely continue.

Further discussion of seasonal temperature anomalies leads to the observation that the change in the probability that the seasonal mean temperature at any given location will fall in the category that was defined as unusually warm during 1951-1980 has increased from 30 percent during that period to about 60 percent today. This will be illustrated in an upcoming publication.

The bottom line?

“The Earth has been in a period of rapid global warming for the past three decades. The assertion that the planet has entered a period of cooling in the past decade is without foundation. On the contrary, we find no significant deviation from the warming trend of the past three decades.”

I haven’t attempted to offer any of the detail with which Hansen builds his conclusions, but can report it as readily accessible to the lay person prepared to give it reasonably patient attention. The essay is another example of his skill in communicating serious science to non-scientists and of his laudable willingness to do so.

His preliminary remarks are worth separate attention. He notes that scientists reporting global warming have come under attack for a supposed conspiracy to manufacture evidence of global warming. Vicious personal messages are sent to the principal scientists almost daily.

“The spiral into an almost surrealistic situation with ad hominem attacks on scientists may have originated in part with vested interests who do not want society to address climate change. But there is more than that – including honest, wishful thinking that climate change is not really happening. But wishing does not alter facts.”

He stoutly supports the work of scientists:

“The scientific method practically defines integrity… All scientists make honest mistakes, but the scientific method is designed to correct them. The skeptical nature of the scientific method causes conclusions to be reexamined as new data appears. Cases of deliberate fudging of data, of scientific fraud, are so rare that these infrequent episodes live in infamy for decades and even centuries.”

He knows of no cases of fraud in analyses of global temperature measurements. In the face of unfounded accusations “our best approach is simply to continue to report our scientific results as clearly as possible.”

He thinks that most of the public continue to respect scientists for what they do and how they do it. I hope he’s right. Sometimes I think the forces of denial have taken on the aspect of a rampaging demonic power, against which the forces of quiet reason are for the time being ineffectual.

Telling porkies to Parliament

NZETS.jpgThe Emissions Trading Scheme Review committee has released the first batch of submissions it has received — those made by organisations and individuals who have already made their presentations to the committee. There are some heavy hitters in there: from New Zealand’s science and policy community there’s the Climate Change Centre (a joint venture between the University of Canterbury and Victoria University of Wellington, plus all the Crown Research Institutes – from NIWA to AgResearch), VUW’s Climate Change Research Institute, and GNS Science, and from the world of commerce, we have the Business Roundtable‘s “evidence”. Why the quote marks? Because the Roundtable’s submission is a fact-free farrago of nonsense.

Continue reading “Telling porkies to Parliament”

Long hot summer

kanga.jpgThere’s record heat in Australia and deep snow in England (with more to come, say Met men), and it’s all consistent with continuing global warming. Over at Wellington’s leading public transport blog, this is enough to inspire a remarkably ill-informed diatribe:

Following the news as I do, it was delicious today to see the global warmers claiming Melbourne’s summer heatwave was proof of Pope Gore’s alarmism, while ignoring the inconvenient truth that the heaviest snowfalls in decades are falling in London, Paris and much of the north-east of North America.

The really inconvenient truth, of course, is that both weather events neatly demonstrate some of the impacts of global warming and the changes in climate that result.

Continue reading “Long hot summer”