Coolwire       17                                 January   2006

In many recent media articles and on their Media Release web page the BoM claim 2005 was Australia's hottest year.

 The BoM began making this claim on 14 November and Warwick  Hughes has been critical  on two main grounds.
[1]    Oddly,  none of  our State Capitals felt the heat extremes over 2005 as shown by the first map below.
[2]     The areas .claimed by the BoM to be the hottest are generally remote, tend to have sparse data points and these tend to have relatively short data span compared to better settled regions of the continent.  Furthermore these remote data tend  to be noisier with greater interannual variation, thus being more prone to indicating spurious trends.

On 4 Jan 2006  the BoM definitively claim "2005 Australia's warmest year on record", in a BoM  Media Release by Greg Hunt the Parliamentary UnderSecretary.

This map is from the 4 Jan 06 media release, " Annual Australian Climate Statement 2005",  Mean Temperature Anomaly map for 2005.

BoM colour anomaly fields are; Yellow = 0.5 to 1.0 deg. Brown = 1 to 1.5 deg. Pink = 1.5 to 2 deg.  Red = 2 to 2.5

As a check on the BoM claims Warwick Hughes  is thus asking, "Which of the major climate research groups agree with the BoM ?"
The first comparison between BoM claims and results from a major global climate group is from those "doyens of Global Warming"  at the Climate Research Unit (CRU) at the University of Norwich lead by Dr Phil Jones.  The Climate Monitor website of CRU publish global maps of grid box anomalies for each month in each year from 1960. I have cropped out the Australian region of their maps for 1998 and 2005 and juxtaposed the two years in the panel below.

CRU 1998 vs 2005 for Australia
"Blind Freddy" can see that CRU  measure 1998 to be warmer than 2005 over Australia.

So, CRU DO NOT agree with the BoM that 2005 was "Australia's warmest year on record" as the BoM claims.
The CRU anomalies for 2005 are similar to those of the BoM.

Comparing  BoM trends for 2005 with satellite data from the Lower Troposphere (LT), there is a very clear result showing 1998 to be a hotter year over Australia than 2005.

Temperature anomalies for 2005 and 1998 from  NOAA  Tiros satellites which have data from December 1978

Let's look at  an alternative map of global temperature anomalies for 2005 just generated by Dr John Christy at the University of Alabama at Huntsville (UAH) using data from NOAA satellites  measuring the Lower Troposphere  layer of the atmosphere approximately  up to 5 miles high.  Full global map.   It is interesting that UAH say 2005 is second warmest year in their global record, equal to 2002.
The pale yellow zone covering the vast area of Australia is indicating an average temperature anomaly of only 0.25 to 0.75 degrees C.
This suggests that the east-west Central Australia warm zone so prominent in the BoM map above became established prior to 1979.
UAH satellite T anomalies Australia 1998
Invoking that well respected Antipodean authority "Blind Freddy", it is clear from the global UAH T anomaly map for 1998 that Australia was warmer that year in the Lower Troposphere than in 2005.

Another gaping hole shot in the BoM Media Releases crowing about Australia's Hottest Year.
The Greenhouse effect must warm the atmosphere first, then that warmer air warms the surface,  so to the extent that the BoM claims association between 2005 heat in their surface anomalies and Greenhouse,  they have some explaining to do in terms of the very weak satellite trends over Australia from 1979.
For many articles explaining the measuring of  global temperature by satellite remote sensing instruments at the University of Alabama at Huntsville.

This anomaly map below for 1 Nov 2004 to 30 Nov 2005 is by Dr Jim Hansen's NASA Goddard Institute for Space Studies (GISS)  in New York  Note the GISS pale brown countouring covering the bulk of Australia indicates plus 0.5 to 1.0 degrees C, while their most intense anomaly for Australia indicates plus 1.0 to 1.5 C. As opposed to the BoM 1.5 to 2.0 and higher.

It gets worse because GISS use a 1951 to 1980 averaging period which was cooler  compared to the BoM 1961 to 1990 period.   So all other things being equal, the GISS anomalies should be  slightly higher than the BoM.
However the GISS data runs from 1880  and these more moderate anomalies over Australia compared to the BoM could reflect the more realistic approach by GISS  to early Australian data.    BoM data only runs from 1910.  GISS do agree with the BoM that 2005 over Australia was warmer than 1998.  Phew !!, that is a relief, we were beginning to think that nobody agreed with the BoM about anything.