NOAA/GHCN “homogenization” falsified climate declines into increases
posted at 8:48 am on December 9, 2009 by Ed Morrissey
At least it did in Australia, where Willis Eschenbach took a look at the raw data to determine what effect the “homogenization” process at the NOAA’s Global Historical Climate Network had on the temperature readings. Like alchemists of old, it transformed decades-long declines in temperature into rapid upward spikes completely unsupported by any of the underlying data. Eschenbach calls this “the smoking gun at Darwin Zero,” and it demonstrates further why the East Anglia CRU (which relied on NOAA/GHCN) conspired to destroy evidence requested in a Freedom of Information demand — and why CRU may have destroyed its raw data archives (via Instapundit and Volokh Conspiracy):
The second question, the integrity of the data, is different. People say “Yes, they destroyed emails, and hid from Freedom of information Acts, and messed with proxies, and fought to keep other scientists’ papers out of the journals … but that doesn’t affect the data, the data is still good.” Which sounds reasonable.
There are three main global temperature datasets. One is at the CRU, Climate Research Unit of the University of East Anglia, where we’ve been trying to get access to the raw numbers. One is at NOAA/GHCN, the Global Historical Climate Network. The final one is at NASA/GISS, the Goddard Institute for Space Studies. The three groups take raw data, and they “homogenize” it to remove things like when a station was moved to a warmer location and there’s a 2C jump in the temperature. The three global temperature records are usually called CRU, GISS, and GHCN. Both GISS and CRU, however, get almost all of their raw data from GHCN. All three produce very similar global historical temperature records from the raw data. …
Then I went to look at what happens when the GHCN removes the “in-homogeneities” to “adjust” the data. Of the five raw datasets, the GHCN discards two, likely because they are short and duplicate existing longer records. The three remaining records are first “homogenized” and then averaged to give the “GHCN Adjusted” temperature record for Darwin.
To my great surprise, here’s what I found. To explain the full effect, I am showing this with both datasets starting at the same point (rather than ending at the same point as they are often shown).
Figure 7. GHCN homogeneity adjustments to Darwin Airport combined record
YIKES! Before getting homogenized, temperatures in Darwin were falling at 0.7 Celcius per century … but after the homogenization, they were warming at 1.2 Celcius per century. And the adjustment that they made was over two degrees per century … when those guys “adjust”, they don’t mess around. And the adjustment is an odd shape, with the adjustment first going stepwise, then climbing roughly to stop at 2.4C. …
Intrigued by the curious shape of the average of the homogenized Darwin records, I then went to see how they had homogenized each of the individual station records. What made up that strange average shown in Fig. 7? I started at zero with the earliest record. Here is Station Zero at Darwin, showing the raw and the homogenized versions.
Figure 8 Darwin Zero Homogeneity Adjustments. Black line shows amount and timing of adjustments.
Yikes again, double yikes! What on earth justifies that adjustment? How can they do that? We have five different records covering Darwin from 1941 on. They all agree almost exactly. Why adjust them at all? They’ve just added a huge artificial totally imaginary trend to the last half of the raw data! Now it looks like the IPCC diagram in Figure 1, all right … but a six degree per century trend? And in the shape of a regular stepped pyramid climbing to heaven? What’s up with that?
Those, dear friends, are the clumsy fingerprints of someone messing with the data Egyptian style … they are indisputable evidence that the “homogenized” data has been changed to fit someone’s preconceptions about whether the earth is warming.
Or, in the Climategate parlance, hide the decline. If what Eschenbach says is true — and he’s looking at the raw data — Australia hasn’t warmed at all, except in the fevered imagination of the GHCN. Did the CRU use the raw data or adjusted data to reach its conclusions? Since they’ve destroyed their raw data, we won’t ever know. But what we do know is that the “adjusted” data looks nothing like the raw data, and the rapid warming is as artificial as the thoroughly discredited “hockey stick” graph that started the AGW hysteria in the first place.
Is the Earth warming? Yes, since 1650, as Eschenbach reports. Is that warming trend natural? Perhaps, perhaps not. In order to make that determination, we need a completely transparent data set, one that is free of “adjustments” from advocates masquerading as scientists. As long as the current set of alchemists remain in control of the raw data, their work should be considered completely unreliable.
Update: I changed the headline to accurately represent where the homogenization occurred.