The National Climatic Data Center wrongly declared July 2012 as America‘s hottest July ever — and hasn‘t corrected itself.First, let's go find the Braintrust's source material. It's here.
Frontier Center for Public Policy advisers Tom Harris, the executive director of the International Climate Science Coalition, and Tim Ball, a former University of Winnipeg climatology professor, give ample reasons to doubt that NCDC claim and its ranking of 2012 as the warmest year on record and one of the top two years for extreme U.S. weather.
Unfortunately, it only takes three paragraphs for these two "experts" invalidate their own case (and thereby the Braintrust's case):
Last summer’s headlines blared, “Hottest July in the history of the United States.” The National Climatic Data Center (NCDC) of the U.S. National Oceanic and Atmospheric Administration (NOAA) said so, so it must be true.Let's star there. Did the Met Office really say all that?
This week, the NCDC is reporting the same, with the added alarm that 2012 was the warmest year on record and one of the top two years for extreme weather in America.
Climate activists are linking this to man-made global warming, ignoring the fact that the area covered in the NCDC reports, the contiguous United States (excluding Alaska), comprises only 2 percent of the Earth’s surface. Trends that may manifest in the United States in no way indicate global phenomena. In fact, the United Kingdom’s Meteorological Office has said that there has been no global warming for 16 years and this week announced that temperatures are expected to stay relatively stable for another five years. [Emphasis added.]
To understand this manipulation of the data, we have to start back in October, 2012 at the Daily Mail:
The world stopped getting warmer almost 16 years ago, according to new data released last week.The headline of the article states that the "Met Office" released the data. But the Met Office itself published a quick rebuttal with this email exchange - which should explain away the Daily Mail's deception:
The figures, which have triggered debate among climate scientists, reveal that from the beginning of 1997 until August 2012, there was no discernible rise in aggregate global temperatures.
This means that the ‘plateau’ or ‘pause’ in global warming has now lasted for about the same time as the previous period when temperatures rose, 1980 to 1996. Before that, temperatures had been stable or declining for about 40 years.
Q.1 [From David Rose, writer of the Mail's article] “First, please confirm that they do indeed reveal no warming trend since 1997.”It's from there that Rose grew his "no global warming in the last 16 years" story - even though the Met Office reiterates its limitations as an observation.
The linear 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) is about 0.03°C/decade, amounting to a temperature increase of 0.05°C over that period, but equally we could calculate the linear trend from 1999, during the subsequent La Nina, and show a more substantial warming.
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.
In fact, Rose is still at it (and I am curious as to why Scaife's Braintrust didn't just go with Rose in the first place). Take a look at this from a few days ago:
Last year The Mail on Sunday reported a stunning fact: that global warming had ‘paused’ for 16 years. The Met Office’s own monthly figures showed there had been no statistically significant increase in the world’s temperature since 1997.And yet again the Met Office explained away Rose's mislead:
We were vilified. One Green website in the US said our report was ‘utter bilge’ that had to be ‘exposed and attacked’.
The Met Office issued a press release claiming it was misleading, before quietly admitting a few days later that it was true that the world had not got significantly warmer since 1997 after all. A Guardian columnist wondered how we could be ‘punished’.
But then last week, the rest of the media caught up with our report. On Tuesday, news finally broke of a revised Met Office ‘decadal forecast’, which not only acknowledges the pause, but predicts it will continue at least until 2017. It says world temperatures are likely to stay around 0.43 degrees above the long-term average – as by then they will have done for 20 years.
The latest decadal prediction suggests that global temperatures over the next five years are likely to be a little lower than predicted from the previous prediction issued in December 2011.Long story short, the "global warming ended 16 years ago" (and therefore it never existed) story's a sham. It's based on a air of arbitrarily chosen starting and ending points.
However, both versions are consistent in predicting that we will continue to see near-record levels of global temperatures in the next few years.
This means temperatures will remain well above the long-term average and we will continue to see temperatures like those which resulted in 2000-2009 being the warmest decade in the instrumental record dating back to 1850.
Decadal predictions are specifically designed to predict fluctuations in the climate system through knowledge of the current climate state and multi-year variability of the oceans.
Small year to year fluctuations such as those that we are seeing in the shorter term five year predictions are expected due to natural variability in the climate system, and have no sustained impact on the long term warming. [Emphasis added.]
It's enough of a sham to overshadow the rest of the "evidence" Harris and Ball put forth. But let me point out one thing. In their article they complain that:
It turns out that the NCDC does not wait for all the data to be received before computing and very publicly announcing the U.S. average temperature and its rank compared to other months and years. While some stations, such as those at airports, send the data quickly via radio links and the Internet, other stations use old paper forms that arrive by mail considerably later.They seem to think that the NCDC presents each monthly report as a final report and that when new data arrives they don't let anyone know that things have changed.
When the printed data finally arrive, the NCDC updates its temperature database, typically “cooling” the country when all the data are used.
Neither the NCDC nor NOAA tells the public and the press that the temperature announcements in previous SOTCs are no longer correct when the complete data set is analyzed.
I guess they missed this caveat on the July 2012 report itself. It's tucked in at the bottom, so if you don't read the whole thing, you'd probably miss it too:
PLEASE NOTE: All of the temperature and precipitation ranks and values are based on preliminary data. The ranks will change when the final data are processed, but will not be replaced on these pages. Graphics based on final data are provided on the Temperature and Precipitation Maps page and the Climate at a Glance page as they become available.If you want a good explanation as to why the "no warming in 16 years" story's wrong, check this out:
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