I’ve moved to WordPress. This post can now be found at Was 2009 The Warmest Year On Record In The Southern Hemisphere?##################
After reading Roger Pielke Sr’s post Reality Check On Science Magazine’s Claim That 2009 Was The Hottest Year on Record in Southern Hemisphere, I plotted Annual GISTEMP Southern Hemisphere Land+Sea Surface Temperature anomalies from 1982 to 2009, Figure 1, and the Annual UAH MSU TLT anomalies for the same period, Figure 2. There’s nothing surprising with those graphs based on Pielke Sr’s post. GISTEMP is showing record 2009 combined surface temperatures for the Southern Hemisphere, while the 2009 TLT anomalies are far from record levels.
The annual NCDC Land+Sea Surface Temperature anomalies from 1982 to 2009, Figure 3, also do not show the record levels in 2009, but the NCDC does not infill with the 1200km smoothing like GISS.
GISS has used OI.v2 SST data since 1982. Figure 3 is an annual graph of SST anomalies for the Southern Hemisphere, and it illustrates that 2009 was not a record year for SST anomalies. That leaves the GISS land surface temperature anomaly data as the culprit.
Hadley Centre data is still not available for December, and they’ve been running late recently. The NCDC and GISS data through KNMI Climate Explorer data should be updated within the next few days, so we’ll be able to do some comparisons and try to determine which of the continents is responsible for the new record GISS Southern Hemisphere temperatures.
OI.v2 SST anomaly data is available through the NOAA NOMADS website:
The GISTEMP Southern Hemisphere Land Plus Surface Temperature data is available from GISS:
The NCDC Southern Hemisphere Land Plus Surface Temperature data is available here:
The UAH MSU TLT anomaly data was retrieved from the KNMI Climate Explorer:
Bob, posted this on WUWT
RE: GISS/UAH SH ‘discrepancy’
Are you sure that the ENSO lag is not playing some part in this, i.e. satellite readings don’t respond as quickly to El Nino development.
The surface temperatures started to rise much earlier in the year. UAH readings for the 6 months since July have been at record levels – higher than the same period in 1998. The SH surface (GISS) temperatures seem to have moderated while it’s not clear that has happened with the satellite temperatures. I think we need to look at the Jan/Feb numbers before jumping to conclusions.
This issue came up some months ago (June??) when UAH was recording near zero anomalies while GISS and Hadcrut anomalies were rising. I reckon there’s a good chance that by May or June, UAH will have recorded it’s warmest ever 12 month period (SH and NH).
Anonymous (6:43AM), John: My reply to you at WUWT is, as of this time, still awaiting moderation. I replied:
Note the difference between the GISTEMP and NCDC data.
Also, this was a quick post, and with the differences in base years, I didn’t create any comparison graphs. There appear to be a few “shifts” in the GISTEMP data that don’t show in the other datasets. I’ll be looking at them in more detail in a follow-up post when KNMI updates.
According to a commenter on recent threads on the Air Vent, vsaluki, GISS is using some heavy extrapolation and interpolation over the pole areas which is leading to highly anomalous results for the poles.
"For example, Hansen’s algorithm takes a row of cells near the Arctic that HadCRUT shows as having a cool anomaly and turns that row into cells having a maximum hot value. In other words, the extrapolation causes a value change for the cells of more than 6.7C."
Perhaps this is the reason for the "discrepancy".
John: You also wrote, “I think we need to look at the Jan/Feb numbers before jumping to conclusions. “
This post is about the claims made by GISS for calendar year 2009. Extending the evaluation is not relevant.
Anonymous (8:21AM): You wrote, "According to a commenter on recent threads on the Air Vent, vsaluki, GISS is using some heavy extrapolation and interpolation over the pole areas which is leading to highly anomalous results for the poles."
GISS uses 1200km smoothing to infill missing data on all continents, not just the poles.
"GISS uses 1200km smoothing to infill missing data on all continents, not just the poles."
Indeed, but the claim is that the sparsity of data at the poles is causing this infilling and extrapolation to over extrapolate, leading to anomalies which cannot be supported by the measurements taken and it is this over extrapolation that is producing trends above those observed in other datasets.
I would therefore predict that when you get round to doing the comparisons, Antarctica will be the continent mainly responsible for the GISS result.
Anonymous 9:03AM: I wasn't contradicting the (your?) prior comment; I was adding to it. Refer to the following post. It's not only Antarctica that gets a warm bias from the GISS 1200km smoothing.
The title of the post is, "Part 2 of Comparison of GISTEMP and UAH MSU TLT Anomalies"
I also think that ANTARTICA is the reason for discrepancy.
There are present very big anomalies, but only during winter (according to NOAA map room).
So, showing a continuous graph with 3-month(seasonal)smooting should confirm or rule out this possibility.
If true, the 2009 warm anomaly will be higher around June-July-August-September.
I guess this is present only in GISS data because the other datasets doesn't include polar regions.
Anonymous (4:57PM): You wrote, "I guess this is present only in GISS data because the other datasets doesn't include polar regions."
Actually, HadCRUT3 data includes the Antarctic:
So does the NCDC when they find the readings to be reliable.
So you need to modify your reason.
araon: Thanks for the kind words, but with the "website develpoment" link, your comment had the appearance of spam, so I deleted it.
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