It is likely that by now you have seen the news that NASA declared that 2014 was the warmest year on record - though as usual the facts aren't quite as simple as that. It turns out the pronouncement was based on land-based sensors - thought to be less reliable than atmospheric measures - and that NASA is only 38% confident it was the warmest year year (though it is much more certain it was a warm year by historical standards).
The increase was also very small - some two hundredths of a degree and subject to degrees of certitude - leading warming skeptics to say the some 16-year long "pause" in global temperatures is still on, contrary to nearly all modes uses to predict rising temperatures from CO2. CO2 levels are in fact increasing, but temperatures are not responding as many climatologists thought.
TheGreenSupplyChain.com was going to write our own views on this dichotomy, but ran across instead a fine editorial from Graham Lloyd, environmental editor from The Australian newspaper. Lloyd does a fine and balanced job of analying the situation, and makes the important point that making environmental policies - especially the speed at which they might be implemented - based on temperature models that do not as yet seem to reflect reality - could be a dangerous proposition.
We offer his take below:
2014 was a Scorcher, but We Can't Ignore the Pause in Global Warming
Graham Lloyd
Environmental editor
The Australian
Global temperatures remained at a high level regardless of whether readings were taken on the Earth's surface, both land and sea, or by satellite for the lower 8km of the atmosphere.
Some suggest 2014 was the hottest year since modern record-keeping began more than a century ago, others put the year just past at No 6.
The difference between the warmest years that have all occurred in the past two decades is so small it is considered statistically insignificant. This is why, while many have been quick to claim the hot 2014 as proof of the relentless march of man-made climate change, others contend it provides further pause for thought.
Last year was notable for the fact that high average global temperatures did not coincide with the onset of a much anticipated El Nino weather pattern, which came close to forming but now looks unlikely to materialise this year.
Japan's weather bureau, the last of the big four international agencies to report its provisional global figure, said this week that 2014 was the hottest on record, confirming preliminary estimates released late last year by the World Meteorological Organization.
National meteorological agencies also confirmed it had been a record year for Britain, France and much of Europe, and the third hottest year for Australia since 1910. Maximum temperatures in Australia overall were 1.16C above average and minimum temperatures were 0.66C above average. Australia's hottest year was 2013, followed by 2005.
For the weather obsessed, dramatic conditions have continued into 2015 with searing heat and bushfires and significant rains in southern Australia coinciding with heavy snow and frigid conditions across much of Europe and North America.
Commentary from the Australian science community says the record temperatures and weather patterns are consistent with "our knowledge of what will occur in a climate under the influence of increased anthropogenic activity".
Sarah Perkins, a research fellow at the Climate Change Research Centre at the University of NSW, says in a statement: "The fact that we are experiencing such record-breaking and extreme conditions, both during consecutive years and since the turn of the millennium, is a clear sign that climate change is happening now and here, in Australia."
Australian National University climate scientist Sophie Lewis says "recent extreme heat in Australia is also consistent with global conditions", adding: "All of the 10 warmest years recorded have occurred since 1998 and it is likely that 2014 will be the hottest year globally."
For much of the media, such comments and the headline figures from the 2014 temperature announcements have been taken as confirmation that the so-called "pause" in global warming had ended or did not in fact exist.
The Washington Post says, "2014 may set a new temperature record. So can we please stop claiming global warming has stopped?"
The Sydney Morning Herald has declared "an amnesty on those still engaged in divisive name-calling and facile arguments" because, it says, the unfolding consequences of a few degrees of temperature change make it time to move on from the climate change debate.
Former Australian climate commissioner Will Steffen says the 2014 results are "the latest in a long string of temperature records we have been setting around Australia and around the world".
While the Bureau of Meteorology was criticised by some academics for not linking the record temperatures directly to man-made climate change, Steffen says the link is clear: "These trends are going to go on and on unless we can stabilize emissions of greenhouse gases.
"We need to do this rapidly, we need to do this deeply and we need to basically decarbonise the world economy by mid-century," he says, mirroring the key message going into this year's critical climate change talks in Paris.
Despite the headline figures, however, 2014 has done little to answer one of the most pressing questions in climate change science: why did surface temperatures stop rising more than a decade ago, even though greenhouse gas concentrations have continued to rise at an accelerating pace?
The pause is acknowledged in the Intergovernmental Panel on Climate Change's synthesis report, which lists a host of possible explanations, and by Britain's Met Office, which has called for urgent research and says the latest figures do not signal it is over.
This is because, although still at a high level, global average surface temperatures are not rising in response to increased atmospheric carbon dioxide levels as climate models had suggested they would
.
According to the Japan Meteorological Agency, 2014 was warmer than the previous record year, 2013, by 0.05C, which is within the margin for error for the data. In fact, the top five global temperature years recorded by Japan - 2014, 1998, 2013, 2010 and 2005 - are all within a 0.1C margin of error. The same is true for the global temperature data released by the Met Office and the WMO.
And it is confirmed by satellite measurements of the lower troposphere, the surface of the Earth to about 8km.
 Figures released by US firm Remote Sensing Systems this week put 2014 as the sixth warmest year on record. And satellite measurements by the University of Alabama in Huntsville rank 2014 as the third warmest in the satellite record.
As in the case of surface temperature readings, the narrow band of satellite temperature data makes ranking problematic.
British Met Office climate monitoring scientist Colin Morice says: "Record or near-record years are interesting, but the ranking of individual years should be treated with some caution because the uncertainties in the data are larger than the difference between the top-ranked years. We can say this year will add to the set of near-record temperatures we have seen over the last decade."
In short, despite the variations, all of the surface and satellite temperature records clearly confirm that global temperatures are at a high level relative to those at the start of the 20th century.
But the narrow range of the recent temperature records, both from satellite and ground-based observations, confirms that the pause continues and big questions remain unanswered.
In contrast to the fierceness with which the issue of the surface temperature hiatus has been received in Australia - where mention of the pause is dismissed as a ploy by "vested interests to spread doubt and misinformation" - it is openly acknowledged in serious scientific debate internationally.
It certainly is possible to accept both the pause and climate change science.
Judith Curry, earth sciences professor at the Georgia Institute of Technology in Atlanta, accepts the earth is warming and that human activity is contributing to it. However, she argues the Earth is warming at a slower rate than computer models predict and she differs with many of her colleagues on precisely what the current pause in surface temperature warming means.
In short, Curry says climate models are not fit for the purpose of climate change attribution on decadal to century timescales.
"Convincing attribution of more than half of the recent warming to humans requires understanding natural variability and rejecting natural variability as a predominant explanation for the overall century-scale warming and also the warming in the latter half of the 20th century," she says.
In recent published research, Curry says the Earth's climate is not as sensitive to rising CO2 levels as climate models suggest.
Even if Curry is correct on the issue of climate sensitivity, it will only slow the impacts of climate change, not avoid them altogether.
Many climate scientists believe the answer to the pause can be found in the ocean, and that it will end with the formation of the next El Nino. But in a statement anticipating a record 2014 — at a time when the formation of an El Nino system in 2015 seemed more likely than it does today - Britain's Met Office said it was too early to say the pause was over.
"The changes seen in the surface temperatures in the Pacific Ocean might suggest that the ‘pause' in global mean surface warming is coming to an end," it said in a statement.
"There is as yet no evidence to support this, but new research has continued to reinforce the role of decadal variations in ocean heat uptake as an important contributor,'' it added.
The Met Office said there was growing confidence that oceans had played a significant role in moving heat away from the surface to the depth, so it is was not visible at the surface as warming, with oceans effectively hiding the "missing heat".
And while the focus of attention remains on the Pacific Ocean as the primary player, the Met Office said it was becoming increasingly clear that others, particularly the Atlantic and Southern oceans, may also contribute.
"More research is needed that must involve a combination of theory, observations and modelling", the Met Office said.
"Observations alone are too sparse in the oceans to describe and understand decadal and longer timescale variations in the ocean circulation and hence ocean heat uptake.
"Since these potentially lie at the heart of the current ‘pause' and therefore how it will eventually end, it is vital that this research is pursued as a matter of urgency," the Met Office said.
By acknowledging the pause, the Met Office does not suggest it reduces concerns about the long-term threat posed by climate change.
But other scientists, such as Curry, argue the pause exposes the weakness of climate models on which far-reaching government policy is based, and emphasize that it needs to be properly understood.
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