The "legitimate" (my word) climate scientists would say, yes, he is wrong.
Perhaps you thought that the whole “planet isn’t warming” meme was killed by this summer’s bombshell Koch-funded study. After all, it found “global warming is real,” “on the high end” and “essentially all” due to carbon pollution.
Sadly, denial springs eternal. Long-debunked denier David Rose has an article in the Daily Mail, “Global warming stopped 16 years ago, reveals Met Office report quietly released … and here is the chart to prove it.”
The piece is so misleading, even the UK Met Office felt a need to instantly debunk it with a blog post that included this chart.
UK Met Office graph showing years ranked in order of global temperature.
Since Rose managed to find one misleading chart to push his myth, I thought I would dig up ten serious ones that show the reverse, including the top chart from Skeptical Science, the great Australian blog, which is derived from the data in the Koch-funded study.
Note: “Skeptics” is an Aussie word for denier or disinformer. The British have their own words — Rose or Mail:
So one has to assume going in that any climate piece in the Mail with Rose’s name on it is somewhere between misinformation and disinformation. The latest piece tends toward the latter. Heck, even Judith Curry complains she was misquoted, as Media Matters notes.
The Met Office, part of the UK Defence Ministry, explained, it’s absurd to look at a cherry-picked “trend from August 1997 (in the middle of an exceptionally strong El Nino) to August 2012 (coming at the tail end of a double-dip La Nina)”:
As we’ve stressed before, choosing a starting or end point on short-term scales can be very misleading. Climate change can only be detected from multi-decadal timescales due to the inherent variability in the climate system. If you use a longer period from HadCRUT4 the trend looks very different. For example, 1979 to 2011 shows 0.16°C/decade (or 0.15°C/decade in the NCDC dataset, 0.16°C/decade in GISS). Looking at successive decades over this period, each decade was warmer than the previous – so the 1990s were warmer than the 1980s, and the 2000s were warmer than both. Eight of the top ten warmest years have occurred in the last decade.
Over the last 140 years global surface temperatures have risen by about 0.8ºC. However, within this record there have been several periods lasting a decade or more during which temperatures have risen very slowly or cooled. The current period of reduced warming is not unprecedented and 15 year long periods are not unusual.
The warming trend is clear in a chart from an earlier Met Office post “Noughties confirmed as the warmest decade on record“:
Here’s an analogy to the notion it hasn’t warmed from the El-Nino-fueled summer of 1997 through the La-Nina-cooled summer of 2012. Imagine your kid got 11 B’s and 1 A+ in 9th grade science class. Then, in 10th grade science, she gets 9 A’s and 2 A+’s — but her last grade was “just” an A. Would you say she is doing better in science class or worse in science class?
If you prefer your charts from U.S. agencies using the good ‘ole Fahrenheit scale, here’s NOAA’s version of the previous chart, which notes “Every year of 2000s [was] warmer than 1990s average”:
The recent La Nina, far from providing evidence that the planet isn’t warming, demonstrates the exact reverse, since it was the hottest La Nina on record — as seen in this chart from NOAA:
See also this discussion of the World Meteorological Organization from December 2011: 2011 Is Warmest La Niña Year on Record and Science “Proves Unequivocally” It’s “Due to Human Activities.”
If you want to refute the disinformers with perhaps the biggest dataset, analyzed independently, and backed by Koch money, well, you have to go to the Berkeley Earth Surface Temperature (BEST) Study — and really, what else is it good for? Their key paper from 2011 found it’s warming fast:
… our analysis suggests a degree of global land-surface warming during the anthropogenic era that is consistent with prior work (e.g. NOAA) but on the high end of the existing range of reconstructions.
They compare their findings with all the other datasets, and it looks like this:
“The decadal land-surface average temperature using a 10-year moving average of surface temperatures over land. Anomalies are relative to the Jan 1950 – December 1979 mean. The grey band indicates 95% statistical and spatial uncertainty interval.” A Koch-funded reanalysis of 1.6 billion temperature reports finds that “essentially all of this increase results from the human emission of greenhouse gases.” Via BEST.
Still warming, though that’s just a chart of land-surface temperatures.
In fact, the land has received only a tiny fraction of the manmade warming in recent years as the scientific literature — captured in this great Skeptical Science infographic — makes clear:
Components of global warming for the period 1993 to 2003 calculated from IPCC AR4 126.96.36.199.
Now, if you actually read the scientific literature, you find the oceans have been rapidly warming in recent decades (see “Hottest Decade on Record Would Have Been Even Hotter But for Deep Oceans“):
“Total Earth Heat Content [anomaly] from 1950 (Murphy et al. 2009). Ocean data taken from Domingues et al 2008.”
And no, the ocean didn’t stop warming in the middle the last decade, as a chart from yet another scientific study makes clear (see “Search for ‘Missing Heat’ Ends Myth Global Warming Has Ended“):
Revised estimate of global ocean heat content (10-1500 mtrs deep) for 2005-2010 derived from Argo measurements. The 6-yr trend accounts for 0.55±0.10Wm−2. Error bars and trend uncertainties exclude errors induced by remaining systematic errors in the global observing system. See Von Schuckmann & Le Traon (2011). Via Skeptical Science.
You may have noticed in the infographic that Arctic sea ice has seen 0.8% of global warming — nearly two-fifths of the warming the continents have received. I wonder what has been happening in the Arctic:
Arctic Sea Ice is melting much, much faster than even the best climate models had projected. The reason is most likely unmodeled amplifying feedbacks. Image via Arctic Sea Ice Blog.
Oh, right, it’s in a death spiral — and that’s just the two-dimensional sea ice extent. Let’s remember that “Experts Warn Of ‘Near Ice-Free Arctic In Summer’ In A Decade If Volume Trends Continue.”
Finally we have the Greenland and Antarctic ice sheets, which each have been getting a mere 0.2% of the warming. Let’s check in on those:
- Nature: “Dynamic thinning of Greenland and Antarctic ice-sheet ocean margins is more sensitive, pervasive, enduring and important than previously realized”
- JPL: Polar ice sheet mass loss is speeding up, on pace for 1 foot sea level rise by 2050
- Greenland Ice Sheet Melt Nearing Critical ‘Tipping Point’
- Large Antarctic glacier thinning 4 times faster than it was 10 years ago: “Nothing in the natural world is lost at an accelerating exponential rate like this glacier.”
That’s ten charts, enough for now, but there are many other physical indicators of continued warming (see “How Can It Be Warming When It’s (Almost) Always Cooling?“)
The Koch-funded Berkeley Earth Surface Temperature Study (BEST) verified three things we already knew:
- Recent global warming has been “on the high end.”
- It’s accelerating.
- The data won’t stop the deniers and their media allies from spreading disinformation, including the myth that it has stopped warming.
Figure 1: BEST land-only surface temperature data (green) with linear trends applied to the timeframes 1973 to 1980, 1980 to 1988, 1988 to 1995, 1995 to 2001, 1998 to 2005, 2002 to 2010 (blue), and 1973 to 2010 (red).
Dana of Skeptical Science has a good post on the denier’s latest spin, “Going Down the Up Escalator,” reposted below.
One of the most common misunderstandings amongst climate “skeptics” is the difference between short-term noise and long-term signal. In fact, “it hasn’t warmed since 1998” is ninth on the list of most-used climate myths, and “it’s cooling” is fifth.
This myth stems from a lack of understanding of exactly what global warming is. The term refers to the long-term warming of the global climate, usually measured over a timescale of about 30 years, as defined by the World Meteorological Organization. This is because global warming is caused by a global energy imbalance – something causing the Earth to retain more heat, such as an increase in solar radiation reaching the surface, or an increased greenhouse effect.
There are also a number of effects which can have a large impact on short-term temperatures, such as oceanic cycles like the El Niño Southern Oscillation or the 11-year solar cycle. Sometimes these dampen global warming, and sometimes they amplify it. However, they’re called “oscillations” and “cycles” for a reason – they alternate between positive and negative states and don’t have long-term effects on the Earth’s temperature.
Right now we’re in the midst of a period where most short-term effects are acting in the cooling direction, dampening global warming. Many climate “skeptics” are trying to capitalize on this dampening, trying to argue that this time global warming has stopped, even though it didn’t stop after the global warming “pauses” in 1973 to 1980, 1980 to 1988, 1988 to 1995, 1995 to 2001, or 1998 to 2005 [see Figure 1 above, Hat-tip to Skeptical Science contributor Sphaerica for identifying all of these "cooling trends."]
As Figure 1 shows, over the last 37 years one can identify overlapping short windows of time when climate “skeptics” could have argued (and often did, i.e. here and here and here) that global warming had stopped. And yet over the entire period question containing these six cooling trends, the underlying trend is one of rapid global warming (0.27°C per decade, according to the new Berkeley Earth Surface Temperature [BEST] dataset). And while the global warming trend spans many decades, the longest cooling trend over this period is 10 years, which proves that each was caused by short-term noise dampening the long-term trend.
In short, those arguing that global warming has stopped are missing the forest for the trees, focusing on short-term noise while ignoring the long-term global warming signal. Since the release of the BEST data which confirmed the global warming observed by all other global temperature measurements, climate “skeptics” have been scrambling for a way to continue denying that global warming is a problem, and focusing on the short-term noise has become their preferred go-to excuse.
The Noisy Group
Unfortunately, those making a lot of noise about the noise (and sweeping generalizations that global warming has magically stopped) include several “skeptic” and/or “lukewarmer” climate scientists, who really should know better. One of these, Judith Curry, is actually a member of the BEST team whose data has been used by climate “skeptics” as “proof” that global warming has stopped. Unfortunately, Dr. Curry herself fed these myths in a rather dismaying interview:
“There is no scientific basis for saying that warming hasn’t stopped…To say that there is detracts from the credibility of the data, which is very unfortunate…This is “hide the decline” stuff. Our data show the pause, just as the other sets of data do. Muller is hiding the decline”
Predictably, Dr. Curry’s comments have been disseminated far and wide by climate “skeptics” who desperately want this myth to be true.
Dr. Roger Pielke Sr. has made similar claims in the comments on Skeptical Science:
“Since 2002, as shown in the lower tropospheric plot and in the upper ocean data, little of that heat has accumulated there. There is not enough melt of sea ice or glaciers to account for it there. “Global warming” has nearly stopped using these two metrics”
Dr. Roy Spencer has taken this argument to the extreme, claiming that based on one cool month in his University of Alabama at Huntsville (UAH) tropospheric temperature dataset, “the troposphere is ignoring your SUV” and that (perhaps sarcastically):
“While any single month’s drop in global temperatures cannot be blamed on climate change, it is still the kind of behavior we expect to see more often in a cooling world”
These climate scientists really should know the difference between short-term noise and long-term signal, and it’s a travesty that they’re misinforming the public, the media, and policymakers by conflating the two concepts.
The Signal Comes Through Loud and Clear
On the other hand, other scientists who understand statistics are doing an excellent job explaining the difference between signal and noise. For example, when asked if BEST showed that global warming had stalled over the last decade in response to the interview with Dr. Curry, Dr. Richard Muller (the BEST team lead) said:
“That’s incorrect…I mean, what they have done is an old trick. It’s how to lie with statistics, right? And scientists can’t do that because 10 years from now, they’ll look back on my publications and say, ‘Was he right?’ But a journalist can lie with statistics. They can choose a little piece of the data and prove what they want, carefully cutting out the end. If I wanted to do this, I could demonstrate, for example, with the same data set that from 1980 to 1995 that it’s equally flat. You can find little realms where it’s equally flat. What that tells me is that 15 years is not enough to be able to tell whether it’s warming or not. And so when they take 13 years, and they say based on that they can reach a conclusion based on our data set, I think they’re playing that same game and the fact that we can find that back in 1980, the same effect, when we know it [was] warming simply shows that that method doesn’t work. But no scientist could do that because he’d be discredited for lying with statistics. Newspapers can do that because 10 years from now, nobody will remember that they showed that.”
What the Science Says
The peer-reviewed scientific literature confirms Muller’s comments. For example, Santer et al. (2011):
“Because of the pronounced effect of interannual noise on decadal trends, a multi-model ensemble of anthropogenically-forced simulations displays many 10-year periods with little warming. A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.”
and Easterling and Wehner (2009):
“Numerous websites, blogs and articles in the media have claimed that the climate is no longer warming, and is now cooling.…We show that the climate over the 21st century can and likely will produce periods of a decade or two where the globally averaged surface air temperature shows no trend or even slight cooling in the presence of longer‐term warming.”
Not only are these short-term “pauses” just noise in the data, but observations show that they are entirely expected, and predicted by climate models (i.e. see Meehl el al. 2011).
Other Physical Evidence of Continued Warming
It’s also important to point out that global temperature measurements aren’t our only evidence of the long-term global warming trend. We’ve observed many physical indicators of global warming (Figure 2).
Figure 2: Physical Indicators of a Warming World
When is Warming Cooling?
When constantly confronted with this myth that global warming stopped in 1998, or 2000, or 2002, or 2005, or [insert year], we wonder why distinguishing between short-term noise and long-term signal is such a difficult concept for climate “skeptics.” They remind us of the Penrose stairs made famous by M.C. Escher – a staircase which people can descend forever and not get any lower. This paradoxical perception of an impossible construction seems to be how climate “skeptics” view the world, which is undoubtedly why they’re willing to risk our future on the hopes that 97% of climate scientists are wrong about climate science.
Info about BEST - financed in large part by Koch Foundation -