Roger Andrews: How NASA GISS Manufactures Warming in the Antarctic

My thanks to Roger Andrews for his continuing efforts to uncover some of the bigger egregious errors and mannipulations in the historical temperature record. Here he examines the long term Antarctic record as published by Jim Hansen’s NASA-GISS.

HOW GISS MANUFACTURES WARMING (LOTS OF IT) IN THE ANTARCTIC
by Roger Andrews

Those pagod things of sabre-sway
With fronts of brass and feet of clay

These lines from Byron’s “Ode to Bonaparte” provide a fitting introduction to this short post, which I’m submitting as a filler while I delve ever more deeply into the regional, hemispheric and global atrocities committed by GISS’s homogeneity adjustments.

One of the more significant unknowns in climate science is what temperatures did in the Antarctic during the first half of the 20^th century, and the reason it’s an unknown, of course, is that there are no temperature records in the Antarctic in the first half of the 20^th century. There are records in the Antarctic Peninsula that date back to the 1940s, but the Antarctic Peninsula covers only a tiny fraction of the continent and temperature trends there aren’t representative of trends on the Antarctic mainland, and there are no records on the Antarctic mainland before the mid-1950s. So the mid-1950s is as far back as we can make meaningful estimates of Antarctic mean surface air temperatures, and here are mine, estimated as always using unadjusted GHCN v2 data:

The regression line shows a few tenths of warming since 1955 but the trend probably isn’t statistically significant. However, the fact that we can’t make estimates of mean Antarctic temperatures before 1955 doesn’t mean that no one publishes any, because GISS does. Here are the GISS mean annual surface air temperatures for the 64-90S latitude zone, which covers the Antarctic plus a bit, superimposed on mine (GISS data here):

The close match between GISS and me after 1955 is encouraging in that it shows that there’s at least one corner of the Earth where GISS hasn’t seriously mutilated the raw data. But GISS bumps Antarctic warming up from little or none since 1955 to two full degrees since 1900 by extending the Antarctic record back to 1904. Here’s where GISS gets the pre-1955 temperatures from:

The 1945-55 temperatures come entirely from stations on and around the Antarctic Peninsula that show much more warming than the mainland stations over the period of common record after 1955, and the 1904-44 temperatures come from a single station – Base Orcadas in the South Orkneys northeast of the Antarctic Peninsula.

Projecting temperatures from the Antarctic Peninsula over the entire the entire 64-90S latitude zone, which covers an area of 25 million square kilometers, is bad enough, and projecting temperatures from  a single record like Base Orcadas over a zone this large is even worse. But it gets worse yet. The map below shows where Base Orcadas is. At 60 degrees 44 minutes south latitude IT ISN’T EVEN IN the 64-90S latitude zone. It’s in the next GISS latitude zone up – the 44-64S zone.

It’s hard to see how data manipulation in the service of global warming could get much more creative than that.

UPDATE 22-10-12  – [EDITED pending review by RA] Roger Andrews added this additional description of some particularly stupid warmist tricks on the re-posted WUWT discussion:

Roger Andrews says:

October 22, 2012 at 8:36 am

Thank you everyone for you comments. I’ll respond as time permits.

But in the meantime another skeleton has fallen out of the closet. In a comment above Tallbloke posted some graphs from Jostemikk, and I reproduce one of them here:

This graph shows that there are in fact two temperature records in the South Orkneys – Laurie Island GHCNv2 and Louise  Laurie Island GHCNv3, which is something I didn’t know when I wrote the post. Laurie Island (GHCNv3), which shows warming, is the one that GISS and just about everyone else uses as “Base Orcadas”. Louise Laurie Island (GHCNv2), which doesn’t show warming, appears as “Base Orcadas”  in the KNMI “adjusted” GHCNv2 data base.

Another graph posted by Tallbloke in an earlier comment further shows that the Laurie Island record, the one that GISS uses, contains a large artificial discontinuity in 1951 that adds maybe 1.5C of overall warming.

Here’s how the Laurie Island and Louise Island records compare when this discontinuity is removed.

Not perfect, but I think good enough to show a) that the Laurie Island record is indeed warming-biased and b) that there’s been no significant warming in the South Orkneys since 1900. [Note] ‘Louise island’ in this plot is Laurie Island (GHCNv2) – TB

So it seems that GISS based all of its Antarctic series before 1945 on a demonstrably contaminated and heavily ‘adjusted’ record from a station located miles outside the Antarctic.