Paul MacRae, July 11, 2008

Mystification is the process of explaining away what might otherwise be evident.

— John Berger, Ways of Seeing

Britain’s Hadley Centre for Climate Prediction and Research is in a spot of bother at the moment.

On the one hand, the Hadley Centre is a firm believer in the hypothesis that humans are the main cause of global warming and that we’re heading toward catastrophe. It even devotes several of its web pages to waving a nagging finger at those foolish enough or unprincipled enough to believe otherwise.

On the other hand, the Hadley Centre, as part of the British Meteorological Office and one of the world’s foremost climate-monitoring sites, is also churning out data showing that the planet isn’t warming at the moment, and hasn’t for the past 10 years or so. Clearly, increasing human carbon emissions aren’t causing the warming that was expected.

What to do?

As principled scientists, the Hadley staff can’t cook the books so the temperature figures fit the hypothesis, although at least one other major climate centre is doing its best to keep its figures matching the hypothesis.1 On the other hand, if the general public got the idea that maybe the planet wasn’t warming after all, despite what it’s been told so often, the people might rebel against punitive carbon taxes and go back to their materialist-loving ways.

The Hadley Centre’s solution is a combination of spin-doctoring and let’s hope nobody notices.

You find the spin in its finger-wagging admonitions that we mustn’t take this non-warming trend at all seriously. Just temporary. Planet’s still warming. Move along; nothing to see here.

So, in its webpage on Climate Facts #1, it says: “There is indisputable evidence from observations that the Earth is warming.” 2 This is hardly controversial; even the pesky warming skeptics who annoy the Hadley Centre so much agree on the earth is, overall, on a warming trend. But, just to make sure we’re clear so far: the earth is in an overall warming trend (interglacial) right now and would be whether humans were a factor or not.

Humans causing ‘most of the warming’?

Hadley goes on: “Concentrations of CO2, created largely by the burning of fossil fuels, are now much higher, and increasing at a much faster rate, than at any time in the last 600,000 years. Because CO2 is a greenhouse gas, the increased concentrations have contributed to the recent warming and probably most of the warming over the last 50 years” (italics added).

So, just so we’re clear: humans are the primary (Al Gore likes to use the term “principal”) cause of global warming – that’s what’s meant by causing “most of the warming.”

But then, Climate Fact #3 tells us: “Earth’s climate is complex and influenced by many things, particularly changes in its orbit, volcanic eruptions, and changes in the energy emitted from the Sun. It is well known that the world has experienced warm or cold periods in the past without any interference from humans” (italics added).

So, just to be clear: humans are causing “most of the warming” at the moment, but not warming in the past, and there are many other causes of warming as well, all natural, and all, one would think, a lot more powerful — solar orbit changes, volcanoes, variations in solar energy — than anything humans could throw at the planet.

The site goes on: “In recent ice ages, natural changes in the climate, such as those due to orbit changes, led to cooling of the climate system. This caused a fall in CO2 concentrations which weakened the greenhouse effect and amplified the cooling. Now the link between temperature and CO2 is working in the opposite direction. Human-induced increases in CO2 are driving the greenhouse effect and amplifying the recent warming” (italics added).

Driving or amplifying? They aren’t the same thing

We’ve got two processes here, described by two different verbs: driving and amplifying. Even though the planet is warming naturally (Fact #1), which would naturally tend to increase CO2 levels anyway, human-emitted CO2 is “driving” the greenhouse effect.

This is an amazing feat when you consider that human-added concentrations of CO2 are only about five per cent of natural carbon emissions every year from factors like rotting vegetation, volcanoes, outgassing from the oceans, and the like. And amazing considering that 90 to 95 per cent of the greenhouse effect is produced by water vapor, not CO2.

Never mind. For the Hadley Centre, five per cent of a trace gas like carbon dioxide (CO2 is only 380 parts per million in the atmosphere, to which human emissions add about 10 ppm every five years) is “driving” the greenhouse gas system.

Then the Centre backtracks a bit and says we humans are “amplifying,” rather than “driving,” the recent warming. How much are we “amplifying” natural warming? Presumably about five per cent. Is an amplification of five per cent enough to produce “most of the warming” we’ve experienced over the past 30 years? It’s unlikely, especially considering that the planet warmed about the same amount from 1850-1940, when human carbon emissions were still relatively low.

Furthermore, in the 1850s the planet came out of more than 400 years of cooling known as the Little Ice Age. Before that, during the Medieval Warm Period (900-1350), global temperatures were up to a degree Celsius higher than today’s. Temperatures were warmer about 2,000 years ago (the Roman Warm Period) and about 3,500 years ago (the Minoan Warm Period).

Natural warming occurs every 1,000 years or so

This means that over the past 5,000 years there’s been a major warming and cooling cycle every 1,000 years or so. The current warming, a millennium after the Medieval Warm Period, is right on track as part of that natural cycle.

In other words, the planet may be going about its natural warming at the moment, with a bit of “amplification” – five per cent? – from humans. “Amplifying” doesn’t mean the same as “driving” the climate, but the Hadley Centre doesn’t make this fine distinction.

Then there’s that pesky decade of warming. To counter this inconvenient truth, Hadley tells us in its webpage on Climate Facts #2 that “the rise in global surface temperature has averaged more than 0.15 °C per decade since the mid-1970s. Warming has been unprecedented in at least the last 50 years, and the 17 warmest years have all occurred in the last 20 years. This does not mean that next year will necessarily be warmer than last year, but the long-term trend is for rising temperatures.”

Translating this into understandable English, the Centre is saying that just because it’s not warming now doesn’t mean it hasn’t warmed in the past, which is hardly news. Therefore, it concludes, because it’s been warm in the past three decades, the planet is going to be warmer in the future.

It was warm from 1850 to 1940, too, but in 1940 the planet cooled for 30 years. However, this cooling can’t happen again, according to the Hadley Centre. How does it know? Because its computers tell it so — the same computers that couldn’t predict the recent 10 years of non-warming.

But why isn’t the planet warming now? After all, humans are “driving” the climate, aren’t we? Well, not quite. As the Hadley Centre tells us in Fact #2: “The recent slight slowing of the warming is due to a shift towards more-frequent La Niña conditions in the Pacific since 1998. These bring cool water up from the depths of the Pacific Ocean, cooling global temperatures” (italics added; incidentally, “slight slowing of the warming” is an unsual way of describing “no warming”).

So the oceans are driving this non-warming through an La Nina (a cold current), overriding our human-caused carbon dioxide. Maybe humans aren’t as powerful a “driving” force as the Hadley Centre would like us to believe after all. And if humans aren’t the main cause of cooling, maybe we’re not the main cause of warming, either.

How Hadley chart buries non-warming

Finally, again, the Hadley Centre is stuck with a bunch of numbers that show the planet isn’t warming, despite its computers’ predictions that human CO2 will warm things up. It can’t sweep this data under the rug so it does the next best thing: it produces a graph that makes the lack of warming barely discernible. Here’s the chart the Hadley Centre uses to illustrate temperatures (actually, temperature anomalies) over the last 157 years:

Hadley Centre temperature data, 1850-2007
Hadley Centre temperature data, 1850-2007

The current flat-lined warming shows as a tiny, horizontal tail on the right side of the chart. If you get out a magnifying glass, you’ll see that, yes, the blue temperature line flattens out after the year 2000. I’ve searched the Hadley site and can’t find any graphic that shows the last 10 years in detail, although the numbers are there as a long list. (But, see Postscript.)

However, on his site, Anthony Watts has produced a graph of the past 10 years, using the Hadley Centre’s numbers.3 Here’s what that graph looks like (I’ve added a red line to show average temperatures).

Anthony Watts chart, 1988-2008, from Hadley Centre data
Anthony Watts chart, 1988-2008, from Hadley Centre data

Why hasn’t the Hadley Centre produced a graphic like this? Isn’t an average temperature that hasn’t gone up in 10 years worthy of public attention? Shouldn’t even a temporary pause in warming be good news? Why bury that news in a tiny fillip at the end of a very long-term chart? Why work so hard to hide the truth?

Because the truth doesn’t agree with the Centre’s hypothesis that humans are the “driving” force behind climate. In short, it’s an embarrassment, and therefore to be underplayed as much as possible.

I argue that much of what the public is told by “consensus” climate science about global warming is misleading, exaggerated, or plain wrong.

The Hadley Centre’s spin effort isn’t exaggerating the data (far from it), nor is it plain wrong — the true figures are on the site. But the Centre is doing everything it can to mislead the public in hopes that the planet will start warming again before the peasants figure out that, maybe, the “consensus” climate science prophets are, in fact, plain wrong.

Hadley Centre chart showing 1950-2007
Hadley Centre chart showing 1950-2007

Postscript: One of the comment posts below has a link to a Hadley chart that shows the last few decades in more detail (see right). The blue and orange lines both show a slowdown in average warming in the last few years, including a startling drop (orange line) in 2008. The graphic can be found at

Of course, this wouldn’t do, so the Hadley programs revised their way of calculating temperatures to produce the rising blue and orange lines that they wanted (see the web page above for the second, revised graph).

It’s worth noting, as well, that the more detailed graph with the obvious fall in temperature is not the graph that the public sees on the Hadley Centre’s “myths” pages.


  1. See Steven Goddard, “Painting by numbers: NASA’s peculiar thermometer,” available at
  2. Available at You can find all the other “facts” on the same set of webpages.
  3. Available at