SciGuy and “No Warming Since l998” Debunked in GRL

For science reporters, it has to be tempting to throw a curve ball at the climate consensus. Especially in red states, it's what a lot of readers want to hear.

Could this be what led Eric Berger, the SciGuy for the Houston Chronicle, to claim that these are "good times to be a climate skeptic?"

He begins, as skeptics usually do, by saying that the globe has not warmed in ten years; to wit:

The planet has not shown substantial warming for a decade now.

But according to David Easterling, of the National Climate Data Center, and Michael Wehner, of the Lawrence Berkeley National Lab, and their paper in the most recent GRL, called Is the Climate Warming or Cooling?, this statement is flat wrong.

First sentence:

Anthropogenic climate change is one of the most contentious scientific
issues of our time. Not surprisingly the issue has generated numerous
blogs and websites with a wide range of views on the subject. According
to a number of these sources the climate is no longer warming, in fact,
some claim the planet has been “cooling” since 1998 [e.g., Investor's Business Daily, 2008].

The critical graph:

The authors explain:

It is true that if we fit a linear trend line to the annual global land-ocean surface air temperature [Smith et al., 2005] shown in Figure 1
for the period 1998 to 2008 there is no real trend, even though global
temperatures remain well above the long-term average. The unusually
strong 1997–1998 El Niño contributed to unusual warmth in the global
temperature for 1998 at the start of this period resulting in only a
small, statistically insignificant positive trend. However, if we fit a
trend line to the same annual global land-ocean temperatures for the
1977–1985 period or the 1981–1989 period we also get no trend, even
though these periods are embedded in the 1975–2008 period showing a
substantial overall warming. Furthermore, if we drop 1998 and fit the
trend to the period 1999–2008 we indeed get a strong, statistically
significant positive trend. It is easy to “cherry pick” a period to
reinforce a point of view…

The authors use this as a jumping-off point, to consider the larger issue statistically (which in no way reinforces the skeptic claim). But I want to stick with the skeptics' claim, and cite their conclusion:

Claims that global warming is not occurring that are derived from a
cooling observed over such short time periods ignore this natural
variability and are misleading.

So Berger repeats a claim that is not just wrong, but "misleading."

It's bad enough for a reporter to be wrong. To be misleading is even worse, because it raises the question of motive. And one suspects Berger knows better. After all, the scientist Berger quotes in the column on the topic of Arctic ice points to the most obvious reason for its recovery this year…La Nina.

Not global cooling.

[And that's not even mentioning the negative Pacific Decadal Oscillation.
Caption: Time series of shifts in sign of the Pacific Decadal Oscillation (PDO),
1925 to 2008. Values are averaged over the months of May through
September.  Red bars indicate positive (warm) years; blue bars negative
(cool) years.  Note that 2008 was the most negative since 1956. From NOAA Fisheries.]

You're better than that, Sciguy…

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