It is certainly hot in South Australia – over 40 degrees on Kangaroo Island. Adelaide is even hotter – about 43 degrees.

One or two very hot spells in a season are not unusual, however. The hottest day I have ever lived through was 46 degrees in the early 80s, also in Adelaide.

Has the last decade been the hottest on record in Australia, as Australia’s Bureau of Meteorology says? I noted a couple of days ago that even it were, this is no reason to assume that human activity is responsible.

In fact, there is no correlation between human production of CO2 and changes in climate, but very strong correlation between solar activity and global temperature change.

I also noted that there have been no new temperature records, hot or cold, in the last decade.

Warwick Hughes has shown that in the case of Darwin and Alice Springs, the temperature data do not supprt the BOM’s claim.

There is also considerable doubt that the BOM has adequately taken into account the Urban Heat Island Effect.

These graphs, also from Warwick Hughes, demonstrate the IPCC orthodox warming of about 0.6 degrees in large Australian cities over the 20th century, but no warming at all in rural centres:

Australian Capital City Temperatures 1882 -1982

Australian Regional Temperatures 1882 -1982

Then there is the fact that data has been carefully ‘corrected’, almost always so that older temperatures are lowered, and more recent temperatures increased.

This graph from Watts Up With That shows adjusted data versus raw data for Darwin over the period 1880 to 2000:

Darwin Raw vs Adjusted Temperatures 1880 to 2000

Then there is the fact the even the warming alarmists at East Anglia CRU found the Australian temperature records so poor they are almost incomprehensible. A couple of quotes from the Climategate emails:

I am very sorry to report that the rest of the databases seem to be in nearly as poor a state as Australia was. There are hundreds if not thousands of pairs of dummy stations, one with no WMO and one with, usually overlapping and with the same station name and very similar coordinates. I know it could be old and new stations, but why such large overlaps if that’s the case? Aarrggghhh! There truly is no end in sight… So, we can have a proper result, but only by including a load of garbage!

OH F%*# THIS. It’s Sunday evening, I’ve worked all weekend, and just when I thought it was done I’m hitting yet another problem that’s based on the hopeless state of our databases. There is no uniform data integrity, it’s just a catalogue of issues that continues to grow as they’re found.

Getting seriously fed up with the state of the Australian data. so many new stations have been introduced, so many false references.. so many changes that aren’t documented. Every time a cloud forms I’m presented with a bewildering selection of similar-sounding sites, some with references, some with WMO codes, and some with both. And if I look up the station metadata with one of the local references, chances are the WMO code will be wrong (another station will have it) and the lat/lon will be wrong too.

So how much confidence can we have in the BOM’s claim that this has been the hottest decade since records began?

Very little.