22 Comments

Interesting. I like these mysteries and I hope you do find out what changed around 1980 at Orcadas. I will try to do a bit more digging myself as I do like a bit of detective work. A cursory look threw up talk of an ozone hole which developed in 1980.

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Aha! Ozone is down on my big list of topics. There's a fascinating website I've gone and lost the link to that is banned from all social media channels that reveals the relationship between warming and Ozone. I'll try and find it...

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Found the link using Brave Search. Have a feast on this...

https://ozonedepletiontheory.info/

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Read it - that might just be the smoking gun then.

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Fascinating, innit? Facebook threw a right tantrum when I tried to share the link, which pretty much says it all these days!

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Could site occupancy levels (say year round people numbers) be a proxy for construction and a heat island? It is a very specific turning point with linear trend after.

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To be clear. I'm thinking that the clear linear trend would NOT support my site occupancy model... but it might.

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It sure would be interesting to see an annual census of site staff and buildings!

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I wondered if there had been any upgrade to their equipment about that time. I couldn't find anything for 1980 but I did find a report from about a 2012 upgrade which is worth looking at:

https://nora.nerc.ac.uk/id/eprint/507222/1/Cabrera_etal_IAGAworkshop_BaseOrcadas_2013.pdf

Also at some point they started having visitors:

https://oceanwide-expeditions.com/blog/a-special-visit-to-orcadas-station

and I read '”There are a total of 20 people at the base: two park rangers and a biologist from the Argentine Antarctic Institute who carry out biological monitoring, sample taking, geodesy, and seismology surveys; three Air Force personnel from the National Meteorological Service who carry out meteorological observation and geomagnetism; and 14 Army and Navy personnel from the Cocoantar who attend to the logistical needs of the base,

https://en.mercopress.com/2022/04/26/argentine-antarctica-bases-now-communicated-through-arsat-satellites

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If they're gearing up for tourists that means accommodation, eats places and all the rest. It also means they need to generate more power for lighting and heating.

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I think it might be more of a quick disembark, weather permitting, as the station is so close to the coast but I am sure they will end up with a gift shop so people can buy fluffy penguins to commemorate their visit..... but thinking about it why not serve food in the gift shop and have a toilet for vistors. It will end up as busy as Everest if they are not careful.

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I offer a little antarctic anecodote. (Many!) Years ago I went out with a guy who had recently returned from a couple of years at the British Antarctic Survey station, he was a chef not a scientist, in charge of their culinary welfare. Anyway, they were supplied with copious amounts of cocoa,which nobody liked, so they spread it all round the buildings to help to melt the snow. It's not evidence of anything, but I feel sure he didn't make it up.

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Crazy!

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Meteostat has the following data for Orcadas as reported by the Python meteostat.stations thingy i.e. from 1957 for daily data, 1950 for monthly.

name country region wmo icao ... daily_start daily_end monthly_start monthly_end distance

id ...

88968 Base Orcadas AQ <NA> 88968 <NA> ... 1957-01-01 2023-06-03 1950-01-01 2021-01-01 5633.412994

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I've managed to scoop the daily data for Orcadas and 2005 is indeed missing

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I found 8 duff entries where min > max:

time tmin tmax

11/09/1957 00:00 -13 -19 duff

21/01/1959 00:00 5.4 3.2 duff

01/04/1995 00:00 -2.4 -4.5 duff

02/04/1995 00:00 -1.2 -7.1 duff

03/04/1995 00:00 0.3 -2.2 duff

28/04/1995 00:00 -0.4 -2.2 duff

29/04/1995 00:00 -1.8 -3.6 duff

30/04/1995 00:00 -1 -2.2 duff

so not 100% reliable data

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and about 13% of readings were incomplete - tmax but no tmin or vice versa

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And some entries are just wrong e.g. a 42 degree daily swing :

22/06/1957 00:00 -23 19 42

suspect that should have been -19

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and from eyeballing a plot of "range"= tmax-tmin (= daytime - nighttime temps ?) I'd say something changed around Feb 2021 as the volatility visibly drops... different kit in use?

Also strange (to me) is that the range plot is consistently annual/periodic with peaks in months 5-8 = midwinter down there with minimal sun. How does that work?

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This is all cracking detective work, Dave! I've been wary of data quality from the outset since the Antarctic is not that equipment friendly and staff at bases have far more to worry about than robust temperature measurement. This week I'll be comparing monthly and daily series for a few more bases with the aim of getting some cleaner annual means for the next article.

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gonna analyse the partial results this eve (probably) and I'll post a link to my data when I've tidied it up a bit.

Meanwhile this article https://journals.ametsoc.org/view/journals/clim/34/7/JCLI-D-20-0538.1.xml addresses your suspicions of heat-island effect (and provides lotsa background detail on Antarctic bases). They say in calm wind conditions (< 5kt?) in the summer there could be a positive temperature bias and have a go at removing it. They also say that Orcadas data pre 1956 hasn't been digitised yet ???.

If you want me to scoop any more base data from Meteostat for you, just let me know

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Well, well, well, our suspicions have foundation! I'll chug along with the monthly data to see what this gives but right now I'm putting money on zero warming due to climate change.

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