Remember the weather at Rutherglen? BoM was right all along, of course!

Do you recall all the kerfuffle a short while ago about the temperature record for Rutherglen? (Graham Readfearn wrote about it at the time, too.) It was pretty obvious to anyone who looked at the data that something changed a few decades ago. The record was adjusted - I should say, straightened out. It was corrected because the data record showed there had been a change at the site.

It didn't stop disinformers kicking up a stink complaining the data had been adjusted and not just adjusted but adjusted "up".. They even roped in Graham Lloyd at the Australian.

Well, they got what they wanted only it's not what they want, I suspect. A diligent BoM researcher did a lot of digging. A lot more than I did. (I only made a couple of phone calls and looked at some BoM data and other stuff on the internet.)

While deniers were chastising BoM for not having someone on hand to hop in a time machine, go up to the research station and look at where the weather station was in the 1950s, one of their people was busy doing the next best thing. Getting records from various different archives.

You can read the result of their efforts here. It's a beautiful little glimpse into history.

Oh. Needless to say, there is very strong evidence, I'd say incontrovertible (don't you love that word) evidence of a station move before 1966. And indications of a change in the weather station in the 1970s. As BoM states:

The need for the adjustment made to Rutherglen data for the period prior to 1966 was determined from an objective statistical test that showed an artificial jump in the data during this period.

While it is not necessary to have supporting documentation to justify correcting a statistically determined artificial jump in the data, it is of interest that the change at Rutherglen is very likely associated with a change in the location of the weather station.

Graham Lloyd will no doubt have an article in tomorrow's Australian, profusely apologising to BoM and chastising Jen Marohasy, Bill Johnston, Anthony Watts and other deniers for (further) besmirching the reputation of the environment section of The Australian.

Don't you think?

[Update: for the answer, see below. Sou: 19 Sept 14]

Congratulations to the scientist at BoM who went above and beyond the call of duty. That is such a lovely account, not just of the history - with photos and maps and records, but an illustration of how back in the 1950s weather was weather and weather stations were used for weather, not climate so much. This example also demonstrates that the science works. That the statistical tests are robust.

It also illustrates how difficult the task must have been for people like Phil Jones and his colleagues at CRU in the early days, trying to put together a climate record of the entire world - on a shoestring budget. They would not have been able to visit every weather station in the world even if they had the funds. They would have been painstakingly putting together a record of the world's temperature trends, based on handwritten records of weather stations all over the world. And all the people in weather bureaux everywhere who've entered data from hand written records into computers. The mind boggles just trying to imagine the humungous task that people have quietly gone about doing back over time, without complaint and without the honour and glory bestowed on them that they deserve.

If you're not careful, you'll find your blood pressure rising, thinking about how carelessly and callously deniers accuse these people of "getting it wrong", cherry picking one example out of hundreds - and deniers don't even get that right as this example shows.

You'll notice, no doubt, that despite all the aggravation heaped on BoM without any reason for it, BoM responded without a trace of snark. Scientists are gracious people, aren't they.

Unlike bloggers:)

Update:

For Billy Bob, disinformer and uber conspiracy theorist. He wanted some information to eyeball. He is one of those people who thinks that a single station at a single site is representative of the entire world. If it hasn't warmed in Rutherglen then it disproves global warming is the gist of Bob's argument.

A single site will show much more variability than a region. A region will show much more variability than a continent. A continent will show more variability than a hemisphere. Global land only surface will show more variability than the entire global sea surface. The global land and sea surface combined will show least variability of all. Averages tend to smooth.

Some places in the world are cooling. Some show no overall trend at all. The vast majority of places on earth are warming, as evidence by the large rise in global surface temperature. At Rutherglen research station it has been getting warmer recently.

I have plotted the max daily temperature for Rutherglen for two periods - the entire history and the period since 1966 (after the break in data). Note these past few years in particular, and how warm even the coolest years were, compared to the past.

Data source: BoM

Data source: BoM

Weather in Rutherglen with WUWT, Jennifer Marohasy and Australia's denier newspaper

Update: see below.

Once again we are drawn into the "making up stuff for the sake of a bad yarn" territory at WUWT (archived here) .

Anthony Watts has written about articles by science denier and "environment" writer for the Australian, Graham Lloyd and one of Australia's resident deniers, Jennifer Marohasy. They are raising a big kerfuffle about the record of temperature trends from the agricultural research centre at DEPI Rutherglen.

I'd normally leave it up to Nick Stokes of Moyhu to analyse denialist claims like this, but he hasn't done so yet. So I'll give it a shot myself.

Rutherglen is wine-grape country just north west of the Great Dividing Range in north eastern Victoria. As well as wine grapes there is dryland farming - animals and cropping, among other things. There has been an agricultural research centre there since the year dot. Well, since the late 1800s - doing viticultural research and education (from 1880), as well as other agricultural research from the early 20th century.  (There used to be two research centres, now one.)

My family has lived in the region since the 1950s. I worked for the Victorian Department of Agriculture in the early 1980s, was on the agriculture faculty at Melbourne Uni in the 1990s, headed the Victorian branch of the ag science professional body for a while, and have since done work with the Victorian primary industries department (including its research arm) so the research centre at Rutherglen is not unfamiliar territory, although I've never worked on site there.

Picking cherries in Rutherglen

Now what the deniers are complaining about this time isn't the mean temperature, nor the maximum daily. Nor is it the climatology of Australia or Victoria or even of the region. What they are talking about is the minimum temperature and in particular, the minimum temperatures up to around the mid-1960s early 1970s recorded at Rutherglen. That's more than forty years ago. A single weather station. The ultimate cherry pick.

I couldn't find another weather station close by that has records going back to the turn of the century, so Rutherglen is about it as far as I can tell. Here is a chart of raw average annual temperatures (from daily). I've included the raw records from Corowa, which is not far away on the Murray as well as Benalla and Wangaratta. Click to view larger.

Data sources: Bureau of Meteorology - Raw as recorded and ACORN-SAT

As you can see from the above, the raw records are shown as lower than the ACORN-SAT (adjusted/corrected) records for the period prior to the gap between 1959 and 1965. I'm not in a position to say why that is the case. I will say that the proper explanation is not nefarious intent. You can leave the conspiracy ideation to deniers who congregate at WUWT. There are any number of plausible explanations for why an algorithm would have detected a break in the record and made an adjustment, some of which I've described below.

One thing you'll notice is where Benalla overlaps with Rutherglen in the earliest records for Benalla, the difference in raw minimum temperature is much less than later on (I've highlighted the two bits to look at). This suggests that BoM was not in error in regard to Rutherglen.