New NOAA study shows no slowdown in global warming
Meteorologist/Science Writer
Friday, June 5, 2015, 12:21 PM - NOAA's newly-updated global temperature records show that there is, in fact, no global warming "pause", a new video gives us a refresher on how greenhouse gases work and "Big Oil" asks for carbon pricing. It's What's Up In Climate Change!
No Global Warming "Pause"
Despite evidence to the contrary, there's been a persistent rumour floating around on the internet and on certain media outlets about a global warming "pause" or "hiatus." In response to this rumour, scientists have been quick to point out that, although surface air temperature records might show that the rate of warming has slowed somewhat over the past 15 years or so, this does not mean that the Earth is no longer accumulating heat from global warming.
It's been known for years that much of the heat trapped by greenhouse gases ends up being absorbed into the oceans, and other factors such as volcanic eruptions and El Nino/La Nina patterns in the Pacific Ocean have their influence on temperatures, sometimes masking the warming trend from greenhouse gases. Scientists have also been researching various phenomena that could also account for a slowdown in warming, and they have come up with many real and valid findings - factors in our atmosphere and ocean that are certainly capable of influencing global temperatures in this way.
Now, though, NOAA - the US National Oceanic and Atmospheric Administration - has released a new study that provides an updated set of global temperatures, carefully examined and adjusted to account for known issues in instruments and data collection that can introduce biases in the results. As the researchers report:
Much study has been devoted to the possible causes of an apparent decrease in the upward trend of global surface temperatures since 1998, a phenomenon that has been dubbed the global warming “hiatus.” Here we present an updated global surface temperature analysis that reveals that global trends are higher than reported by the IPCC, especially in recent decades, and that the central estimate for the rate of warming during the first 15 years of the 21st century is at least as great as the last half of the 20th century. These results do not support the notion of a “slowdown” in the increase of global surface temperature.
Credit: NOAA National Centers for Environmental Information
Where does this updated analysis come from? According to the study:
Changes of particular importance include: (i) an increasing amount of ocean data from buoys, which are slightly different than data from ships; (ii) an increasing amount of ship data from engine intake thermometers, which are slightly different than data from bucket sea-water temperatures; and (iii) a large increase in land-station data that enables better analysis of key regions that may be warming faster or slower than the global average. We address all three of these, none of which were included in our previous analysis used in the IPCC report.
What of the other temperature records, from other agencies around the world, that support the "pause" - including the latest IPCC report?
"Before this update, we were the slowest rate of warming," Thomas Karl, director of the NOAA’s National Centers for Environmental Information (NCEI) and lead author of the study, told the Washington Post. "And with the update now, we’re the leaders of the pack. So as other people make updates, they may end up adjusting upwards as well."
And what of the research that's been done over recent years, to account for how a "pause" could develop? Karl told the Washington Post that the phenomena discovered in the research are very real and they did cause cause a slowdown in warming - just not to the point where the rate of warming actually slowed. Instead, these factors kept the warming trend from spiking even higher.
"Those things won’t persist, and when they’re gone, that means the rate of temperature is free to increase even more than it would have," Karl said in the interview. "And you can make the case that had those factors not been operating, we might be talking now about why the temperatures have been warming more rapidly."
How are other researchers reacting to the study?
As Penn State climate scientist Michael E. Mann noted in an article on EcoWatch:
"As I have commented numerous times before, there never was any 'pause' or 'hiatus' in global warming. There is evidence, however, for a modest, temporary slowdown in surface warming through the early part of this decade.
"As my colleagues and I discussed in our own article in Science earlier this year, that slowdown appears to have been tied to an interdecadal period (through at least 2012) of more La Nina like conditions, stronger trade winds in the Pacific and greater burial of heat beneath the ocean surface.
"Does the new article contradict evidence for the slowdown? Upon closer inspection, the answer seems to be no."
In his analysis of the findings, Mann notes that the study makes comparisons to the warming trend over the entire second half of the 20th century. This is a slight problem because it includes the 1950-1970 period - a period of relatively little warming, which Mann says is due "primarily to the cooling effect of industry-generated sulphate aerosol pollutants."
According to Mann, comparison to the period after that, the late 1970s through the year 2000, gives a better comparison, since it follows the signing of the Clean Air Act. During this period, as sulfur dioxide emissions fell in accordance with the Act, the warming effect of carbon dioxide and other greenhouse gases dominated.
Also, including 2013 and 2014, which Mann says are "post-slowdown" years, naturally raise the rate of warming, since they reflect the developing El Nino conditions in the Pacific.
"That late 20th century interval is arguably the more relevant period for comparison, and relative to that period, there was indeed a subsequent short-term slowdown," Mann wrote. "The temporary slowdown is an interesting feature in its own right as it is relevant to the matter of decadal climate forecasting. But it never contradicted the unabated nature of human-caused warming."
"To the extent this latest study adds yet another nail to the "warming pause"/"warming hiatus" coffin," he added "I feel it is a useful contribution to the literature and to the larger discourse over human-caused climate change."
How Do Greenhouse Gases Work?
The ideas behind how greenhouses gases work isn't exactly rocket science, but it is very interesting science, and there's a lot more going on than one might think.
Here to explain just how these gases trap heat in Earth's atmosphere is Henry Reich, from MinuteEarth:
Unlike Henry's usual videos, which he very skillfully drawns in "stickfigure" form, the animation for this one was provided by the good people at Kurz Gesagt, who have produced some pretty amazing videos of their own. Check them out!
"Big Oil" Is Ready For Carbon Prices
One of the big criticisms leveled at "Big Oil" is that - as far as how they're providing energy now and their plans for the future - they are just as much of a "dinosaur" as the stuff they're pumping out of the ground. With the rise of clean energy like solar and wind, they're eventually going to "go extinct" unless they adapt.
Well, it now appears as though they're ready to adapt to the realities of our changing climate, and to the future changes in the energy market.
CEOs from the BG group, Shell, BP, Total, Statoil and Eni have signed their name to a letter addressed to Executive Secretary of the UNFCCC Christiana Figueres, recognizing the challenges of climate change and the need to reduce greenhouse gas emissions, and indicating their willingness to take part in reduction plans.
This is a very smart move on their part, to emphasize their role as "energy" companies rather than "oil" companies. With setting carbon prices now, these companies can better plan for their long-term future (and the long-term future of their investors), and rather than extinction, they can look forward to providing the world's energy from other, cleaner sources as the market shifts away from fossil fuels.
Sources: Science | Washington Post | EcoWatch | MinuteEarth | Climate Central
