This is the second of several posts responding to a reader, sTeve, who commented on my NOAA blog article (to read the first post, click here).  sTeve wrote, in part:

You offer the cherry-picked denier meme of the earth “cooling since 1998″, yet you already know that that argument has no merit, as it has been debunked countless times. You don’t mention the very strong El Nino of 1998, which had a major impact on global temps; perhaps you should read the papers written on that subject. Here’s a link to get you started: www .

You already are aware that 1998 is no longer the warmest year on record, having been surpassed by both 2005 and, so far, 2010, yes?

When I first read this from sTeve, I was astonished, just as I was astonished by NOAA’s recent announcement that the planet had warmed .2° Celsius in the decade 2000-2009. Where had sTeve gotten this data? 2005 and 2010 warmer than 1998? Fortunately, a post by Steve Goddard on Anthony Watt’s Watt’s Up With That? site provided the answer.

Temperature estimates

Figure 1 is the Goddard Institute of Space Studies (GISS) estimate of temperatures from 1880 to 2010 and, sure enough, in the upper right corner, the temperatures for 2005 and 2010 are shown as higher than 1998—considerably higher, actually.

Figure 1: GISS temperature estimate 1880-2010

However, the temperature estimates from the other three major climate monitoring agencies—the Hadley Meteorological Centre (HadCrut), University of Huntsville at Alabama (UAH) and Remote Sensing Systems (RSS)—all show temperatures for the last decade considerably lower than the GISS estimate. In fact, they even show some cooling. The latter two agencies, UAH and RSS, rely on satellite data, which many regard as more reliable than ground temperature estimates. The  UAH reading is shown in Figure 2.

Figure 2: UAH temperatures

Figure 3 shows the two satellite-based agencies combined:

Figure 3: UAH and RSS temperature estimates

Neither UAH nor RSS shows 2000-2010 temperatures as higher than 1998. In fact, the last decade’s temperatures are considerably lower.

Finally, Hadley, the other major ground-temperature monitoring agency apart from GISS, has 21st century temperatures as shown in Figure 4. Once again, 1998 is well above any temperature up to 2010. (The green line is the temperature trend from 1998-2010: flat. No warming.) Indeed, as noted in my previous post, the Climategate emails show Hadley operatives in near-despair over the warming that was supposed to be occurring and didn’t.

Figure 4: Hadley temperatures from 1995 to 2010.
Figure 4: Hadley temperatures from 1995 to 2010.

Finally, Figure 5, from Goddard’s post, shows a comparison of the trend estimates by GISS, Hadley, UAH and RSS:

Figure 5: GISS, Hadley, UAH and RSS trends compared

The fast-rising green line is GISS, blue is UAH, purple is RSS and the bottom red line is Hadley. Both RSS and Hadley show slowly rising temperatures from 1998, a mere .02°C in 12 years. UAH is in the middle, with a temperature increase of .04°C for the decade, also a low figure. GISS, on the other hand, shows an increase of almost .2°C. In other words, for RSS and Hadley, any temperature increase in the past decade has been statistically insignificant(.02°C). Which is what former Hadley director Phil Jones said in February 2010 in an interview with the BBC: there has been no “statistically significant” warming since 1995, and since 2002 there may have been some cooling, although he doesn’t consider this cooling “statistically significant.” Of the two options, though, he prefers the “statistically insignificant” warming over the “statistically insigificant” cooling.

GISS estimates seem suspiciously high

As Goddard notes in his post, although not in quite these words, the GISS estimate is suspiciously high. Another Goddard post has two GISS charts—raw and “adjusted”—alternating to show the extent of these adjustments. Why would GISS do this? Could it be because GISS is run by James Hansen, one of the most rabid of the warming doomsayers, and someone with a huge vested interest in showing temperatures as going high—very high?

After all, it was Hansen who, in 1988, started global warming alarmism on its way with his estimates of very high temperatures in the coming decades, as shown in Figure 6 (from a post by UAH climatologist John Christy):

Figure 6: James Hansen estimate in 1988

More recently, Hansen has predicted that sea levels will rise five metres (16 feet) over the next century due to carbon-caused warming, a view that is extreme even by warmist standards, and Hansen has even urged sabotage of coal plants. In other words, Hansen’s reputation, both scientifically and politically, is hugely dependent on the planet continuing to warm uncontrollably.

(And, as an aside, here’s why I tend to dismiss most of the material coming from the Skeptical Science site that sTeve recommends. A recent post there defended Hansen’s 1988 estimates as consistent with the temperature record over the past two decades. However, to defend Hansen, the writer has to use the GISS temperatures, which appear to be inflated. And the writer prefers to dismiss Hansen’s wilder claims, the two higher estimates (GISS-A and -B), as “what if”, outlier possibilities. In fact, as Hansen’s bizarre recent claims reveal quite clearly, the extreme claims were the predictions he believed in 1988 and believes today are most likely. Hansen’s predictions are wrong. Period. Why not just accept that?)

Hansen’s vested interest could explain why, as Goddard notes in his post, the GISS temperature estimates are consistently “adjusted” to be higher than the other agencies. It is clearly the GISS figures that NOAA used when it made its (absurd) claim that the past decade had increased in warmth by .2°C, which is a third of the warming for the entire 20th century. Meanwhile, according to NOAA’s own figures, the United States dropped in temperature by .4°C (see for yourself by clicking here).

Temperatures ‘adjusted’ in New Zealand, too

From New Zealand comes another example of climate alarmists “adjusting” temperatures upward to claim global warming that isn’t, in fact, occurring, as shown by Joanne Nova‘s excellent blog. The New Zealand temperatures from 1853-2008, as “adjusted” by New Zealand’s National Institute of Water and Atmospheric Research (NIWA), show an increase from 1909-2008 of .9°C. (By comparison, the IPCC’s estimate of the global temperature increase over the whole of the 20th century is only .6°C.) NIWA’s temperature graph is shown below (Figure 7). Note the rising temperature line from 1909.

Figure 7: New Zealand temperatures from 1853-2008, adjusted to show an increase of .9°C over the past 100 years.
Figure 7: New Zealand temperatures from 1853-2008, adjusted to show an increase of .9°C over the past 100 years.

However, NIWA also publishes its raw temperature records. When skeptics used the raw, “unadjusted” numbers, they got Figure 8, which shows a flat temperature trend:

Figure 8: Unadjusted temperatures from 1853-2008, showing a flat temperature trend.
Figure 8: Unadjusted temperatures from 1853-2008, showing a flat temperature trend.

In other words, NIWA had reworked its temperatures, as GISS does, to get warming, even considerable warming, where none existed. And so, while most scientists change the hypotheses to fit the data, alarmist climate scientists prefer to change the data to fit the anthropogenic warming hypothesis.

The other intriguing aspect of the New Zealand case is that when the New Zealand Climate Science Coalition took NIWA to court over its distorted figures, NIWA claimed there is no “official” temperature record, and therefore it couldn’t be held responsible for what the figures showed. However, NIWA was quite happy to promote the data if it showed a warming trend that, as the skeptics have pointed out, is essential to NIWA members getting large research grants.

Summing up: My question for sTeve is: why would you choose the GISS estimate of temperatures, which shows parts of the past decade as higher than 1998 and considerable average warming, over the other three monitoring agencies, which show much less or no warming for the decade? How can you be so sure—”dead sure”—that GISS has got it right and the others don’t? Why are you so uncritical of Hansen’s failed prediction in 1988, despite what Skeptical Science says? And why accuse skeptics of being “dead wrong” when the skeptical perception of climate in the last decade is consistent with Hadley, RSS, and UAH (i.e., no statistically significant warming)? Why not keep, at least, an open mind?

In a future post I’ll deal with a few more of the issues brought up in sTeve’s comment, which, again, can be read in full by clicking here.