Milankovitch cycles

[Lisiecki and Raymo (2005) used measurements of δ18O in benthic foraminifera from 57 globally distributed deep sea sediment cores, taken as a proxy for the total global mass of glacial ice sheets, to reconstruct the climate for the past five million years]

I read yesterday of a much grander cycle of climate change into which the current global warming episode can be inserted: a cycle which until about a million years ago oscillated at 40 thousand years and since then at 100 thousand years. A grander cycle about which we appear to know a great deal, plenty enough to run climate models. Data which is mostly derived from analysis of subtle changes in composition – in terms of chemicals or of remains of life – taken from cores of ice or cores of sediment. The point of these last two being that they give you a record over long periods of time.

The argument of the present paper (reference 1) is that there was a run of very cold glacial periods around a million years ago, cold enough to push hominins back from their foothold in Portugal. Hominins did not just arrive there from Turkey (or thereabouts) and stay, they had to have several goes at it.

Plus a certain amount of AMOC flip-flopping, the present possibility of which exercises global warming people.

[Part of Figure 1 from the present paper. Age estimates of European and SW Asian early hominin sites and paleoclimate context. 0.7mya left to 2.2mya right. a, Obliquity variations. b, benthic oxygen isotope record from Eastern Equatorial Pacific Site ODP677]

[Location of Site ODP 677]

Glossary

Atlantic meridional overturning circulation (AMOC). It is characterized by a northward flow of warm, salty water in the upper layers of the Atlantic, and a southward flow of colder, deep waters. The AMOC is an important component of the Earth's climate system, and is a result of both atmospheric and oceanic (thermohaline) drivers.

Benthic oxygen isotope records are commonly used as a proxy for global mean surface temperatures during the Late Cretaceous and Cenozoic, and the resulting estimates have been extensively used in characterizing major trends and transitions in the climate system and for analysing past climate sensitivity.

Marine isotope stages (MIS), marine oxygen-isotope stages, or oxygen isotope stages (OIS), are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data derived from deep sea core samples. Working backwards from the present, which is MIS 1 in the scale, over 100 stages have been identified so far, going back some 6 million years.

Mid-Pleistocene transition (MPT). From 1–3 million years ago, climate cycles matched the 41,000-year cycle in the earth’s obliquity. Around one million years ago, there was a switch to the matching the 100,000-year cycle in eccentricity. The transition problem refers to the need to explain what changed one million years ago

Milankovitch cycles. The collective effects of changes in the Earth's movements on its climate over thousands of years. The Earth's rotation around its axis, and orbit around the Sun, evolve over time due to gravitational interactions with other bodies in the solar system. The variations are complex, but a few cycles are dominant. See reference 2.

Ocean Drilling Program (ODP) Site 677 provided excellent material for high resolution stable isotope analysis of both benthonic and planktonic foraminifera through the entire Pleistocene and upper Pliocene. Site 677 was cored using the Advance Piston Corer (ADC) at 1°12'N, 83°44'W in 3461m depth of water

Stadials and interstadials are phases dividing the Quaternary period, or the last 2.6 million years. Stadials are periods of colder climate, and interstadials are periods of warmer climate. Each Quaternary climate phase is associated with a Marine Isotope Stage (MIS) number, which describes the alternation between warmer and cooler temperatures, as measured by oxygen isotope data. Stadials have even MIS numbers, and interstadials have odd MIS numbers.

Vostok. Ice cores have been studied since the early 20th century and depths of over 400m were reached in the 1950s, a record which was extended in the 1960s to 2164m at Byrd Station in Antarctica. Soviet ice drilling projects in Antarctica included decades of work at the Vostok Station, with the deepest core reaching 3769m. Numerous other deep cores in the Antarctic have been completed over the years.

Other matters

I have also come across two more new-to-me words: cosplay and marplot. With cosplay being what people who like to dress up as characters – for example Batman or Mickey Mouse – in popular culture or in computer games. And with marplot being a person who mars someone else’s plot. Someone who interferes unhelpfully in other people’s business. See references 3 and 4. I think the first turned up in the Economist and the second in Henry James.

Conclusions

Once again I have been impressed both by the amount that we know about the past and by the amount of knowledge that is more or less freely available from the comfort of one’s armchair.

References

Reference 1: Extreme glacial cooling likely led to hominin depopulation of Europe in the Early Pleistocene – Vasiliki Margari, David A. Hodell, Simon A. Parfitt, Nick M. Ashton, Joan O. Grimalt, Hyuna Kim, Kyung-Sook Yun, Philip L. Gibbard, Chris B. Stringer, Axel Timmermann, Polychronis C. Tzedakis – 2023. My copy being an author manuscript rather than the finished paper.

Reference 2: https://en.wikipedia.org/wiki/Milankovitch_cycles. 

Reference 3: https://en.wikipedia.org/wiki/Cosplay.

Reference 4: https://en.wikipedia.org/wiki/Busybody. 

Trolley 606

There were still some remnants of the herd mentioned at reference 1 yesterday, or perhaps they were replacements. But this trolley was a stray, taken a little nearer the High Street, just by the front entrance of T.K. Maxx.

Then, off around the Sainsbury's circuit, not finding any of their trolleys on the way. Not even at the once reliable accommodation block for the creationists on East Street.

And cholesterol was off at Sainsbury's. The Fresh Kitchen cafeteria had been given over to storage and access was closed off, albeit in a rather half hearted way, and even the cholesterol caravan was shut. The shop itself looked busy enough though.

Plenty of litter and leaves in the alley to the side of the store, the one leading to the footbridge over the railway. No doubt they will get around to it in the lull after the holiday.

Might have been tempted by a festive beverage at TB, except that, around noon, they were shut too - and we did not get around to it later in the day.

PS: curiously, while I can find various pages on the Internet about Sainsbury's pulling the Fresh Kitchen operation a decade ago, I can find nothing about the much more recent closure at Kiln Lane. Perhaps this last had a left-over Fresh Kitchen sticker on the window, but was no longer a proper Fresh Kitchen, just a common or garden cafeteria. I then wonder what the staff do now - apart from pulling refreshments off the shelves that is: there must be 100 or more of them on site when the place is busy and one might have thought there ought to be something for them.

References

Reference 1: https://psmv5.blogspot.com/2023/12/trolleys-604-and-605.html.

Group search key: trolleysk.

Trolleys 604 and 605

A regular herd of trolleys at the junction between the Kokoro passage and the ramp up to Station Approach. Three trolleys and two trips to the back of the M&S food hall, so scored as two trolleys. The rest left for any other collectors who might have been prowling about.

We celebrated by taking a few beverages in Wetherspoons, pleasantly busy and cheerful, late afternoon on Saturday. Mainly older people like ourselves, with just some younger people moving into festive gear. Apart from the staff that is, who were mostly pretty young. Quite likely students clocking up a bit of money during the holiday.

Only one bad note, two ladies squabbling over seats. One at fault, the other excitable. The young pot-man did not have a clue how to deal with it, but after a while the manageress came over and sorted it out. A manageress who knew her stuff, mixed with the customers and mixed in with the work, helping to clear tables. A credit to the organisation. Sporting a discrete head set to keep in touch - presumably an open channel job.

By the time we left, the excitable lady had calmed down to cheerful and jolly and a couple of rather amateur looking security people had arrived at the front entrance, perhaps more serious security people would be coming on a bit later.

References

Reference 1: https://psmv5.blogspot.com/2023/12/bit-of-stretch-to-score-this-trolley.html.

Group search key: trolleysk.

Dulwich

I have been taking an interest in Rubens lately, so as noticed at the end of reference 1, I got myself to Dulwich Picture Gallery, which I now know was in business before the National Gallery, in the early nineteenth century. A place which we have been to before, but a long time ago now; I would not to hazard a guess as to exactly when.

A cold, dull morning. Plenty of spaces left in the NCP car park at the foot of Station Approach. The best way appeared to be to get to West Dulwich via Victoria, so train to Victoria it was.

Some probable Wellingtonia on the way, as previously noticed at reference 3. Probably not to be checked up on now until the New Year.

Then there were some festive tents between Battersea Power Station and the river. Not clear how temporary they were. Somewhere else to be checked up on.

Then, pulling into Victoria station, a proper diesel electric locomotive, number not visible, class not known. Then, on arrival at Victoria station, it went one better with a full-on puffing Poirot. One of the chaps minding the fence thought that the circular rides on offer were very expensive. £20 a head? £30 a head? It looks from the web site as if excursions are done for this year and prices, never mind excursions, are no longer available.

No.45231 and Wikipedia knows all about it at reference 4. One of a class of 842 locomotives - which makes one wonder how many steam locomotives there were altogether. Not the sort of thing that one supposes were exported in large numbers, despite Ireland shipping its locos in from the US after independence.

Fine tender full of air-polluting, global warming coal. Could you do them for trade descriptions if they had converted to gas - or even hydrogen - without letting on?

Full size figure sculptures to be seen at Brixton Station.

Out at West Dulwich, with what I took to be a large red-brick school visible right and with Gallery Road more or less straight across. Gallery maybe ten minutes away. Turning out to be off-snap to the right in the snap above. I didn't find out what the chapel like building left was, let alone get in it. Perhaps I should have bought the gallery book which was no doubt available from the shop.

The exhibition turned out to be of modest dimensions, two or three not very big rooms connected by a corridor. Lots of sketches and some lesser works. I wondered whether some artists were touchy about their sketches surviving to be pawed over by arty academics - rather in the way that some writers are touchy about their letters surviving them to be pawed over in the same sort of way. I believe that Henry James, for example, burnt most of his large holding of letters.

An interesting early Adam & Eve, part of which is snapped above.

I think it usually lives in the Rubens House in Antwerp, where they offer the commentary above. I was interested in his treatment of the landscape behind, with his treatment of trees reminding me of the way that 20th century wood engravers did their trees. Also in the curiously pterodactyl-like creature flying over the water. Perhaps it is really a cormorant or a heron.

I rather liked this sketch, which seemed to have a bit more life than some of the more finished paintings. With a composition which seems to pop up in one form or another all over the place - for example in Poussin's 'Dance to the music of time' to be found in the Wallace Collection. As it happens, this gallery ran to a few (what I thought to be) inferior Poussin's too. In one or two of which Poussin only seemed to be really interested in painting the intricate folds and colours of the cloaks, with the other stuff getting rather summary treatment.

Also in the gallery proper, there were some rather striking work by one Sara Shamma, to be found at reference 6. And I had forgotten that Canaletto did time in London: I wondered on this occasion how often somebody bothers to check the large number of churches towers and steeples to be seen in the view of London snapped above. Had he counted or was he just doing an impression of lots? There was also a view of a curious bridge at Walton, which reminded me of the mathematical bridge at Cambridge, snapped below.

The point of this one, as I recall, was that it did not, when built, require any bolts, but then someone took it to pieces and couldn't put it back together again. A recollection which does not tally at all with the explanation to be found in Wikipedia.

But maybe I did better with the association to the bridge at Walton. Presumably the upon Thames one.

A painting by Antony van Dyck of Venetia Stanley, Lady Digby, on her deathbed. One wonders how much time he had to spend with the corpse to make the necessary sketches. Not the sort of thing one can see happening in the UK now - although I believe some parts of the world still support what we would regard as pretty fantastic funerary customs. Not happening in the UK at the behest of the surviving partner that is - but not so far removed from the goings on of the scene-of-crime people if television dramas are to be believed.

I din't find out what this was place at the time, but Google images identifies it fast enough as the College of God's Gift, possibly the original site of the big school already mentioned above, possibly now a supported living operation, all sketchily described at reference 7.

Came out to the east of the gallery, which confused me as I had gone in by the west. But a helpful passer-by got his phone out and all was revealed. Back on the right road.

This building was advertised outside as a bar and restaurant and I had hopes of taking refreshment, but it was very firmly shut. An event operation rather than a walk-in. Belair House of reference 8 - which today suggests that it was open all along. Perhaps I had to try a bit harder.

Passed a special parking space marked out in the road for electric bicycles, scooters and so forth. Regularised to that extent, and I have noticed similar spaces here and there since.

An approximation to a bacon roll from a stall opposite the station, heated up in two halves in one of those fold-over toasting contraptions. A lot of salt and a lot of calories. Tea rather better, despite being in a paper cup.

Very full litter bins in and around the station. Which made one think: Dulwich might be an expensive suburb, but not an expense which runs to looking after their litter bins. Then having been sensitised to litter in this way, on the train I noticed a young man stuffing a banana skin down the side of this seat while talking to his telephone about talking to a friend of his out on license. I was all ready to think the worse of him, but, as it turned out, he took his banana skin with him when he left.

I thought about getting out at Brixton, but didn't. I thought about getting out at Clapham, but the train didn't stop there. Out at Victoria where I failed to find a litter bin for my litter at all, but eventually found a cleaning lady with a trolley to which she invited me to contribute. I think she also said something about security seeing off the regular bins.

Upstairs Wetherspoon's shut, a place I used to enjoy from time to time on the way home. Fine view of the goings on on the concourse.

Settled on going to Tooting Broadway via Balham. There was a chap near me sharing his telephonic noise aka musical art on the train, a chap whom I thought was challenging me to challenge him. But I didn't and I got off that hook by his getting off at Clapham Junction.

We pass over the puffing Poirot, somewhere near Battersea.

By tube to Tooting. Pleased to find that the self winding clocks from New York are still to be found at Balham. A type of clock possibly first noticed at Tooting Broadway at reference 9.

Wetherspoon's at Tooting Broadway had not changed much, with some of the original artwork still present, from what must be near thirty years ago, when Wetherspoon's was not long started and a far cry from what it is now. Pleasantly busy with a buzz of conversation not helped along by musak or television. Quite a lot of solitaties who appeared to be watching films on their telephones, propped up in front of them. The bookshelves had been thinned out, but I still managed a paperback from Bloodaxe featuring poems and photographs from one Ahren Warner: 'Hello, your promise has been extracted'. Of passing interest. A well-made paperback with four sewn signatures.

Onto the Half Way House at Earlsfield, my first visit for a while. No sensible snacks, but they could offer pork scratchings, freshly scratched, as it were, on the premises. I was a bit nervous about my fillings, but eventually I worked my way through them, cheating with a certain amount of breaking by hand rather than by tooth. Fresh, tough when thick and not of tasting of much.

Back onto the platform for a shot at the aeroplane game. Low cloud, but nearly dark and the lights of the aeroplane's showed up well. I heard more planes than I saw, but in 15 minutes I did manage two two's and two two minuses. Whereby a two minus, I mean a two where the first aeroplane disappeared to the west only a few seconds before the second appeared in the east.

Remaining leg of the journey occupied by a young working mum, perhaps in her mid twenties, on her telephone, trying to convince her young child, with a minder for the day, that she was just about to pick him or her up. 'Just start to do something dear and I'll be there before you know it'. At least half an hour in my estimation and it did not sound like the child was convinced either.

PS: Warner has been reprieved. Maybe more to it than I gave it credit for on the day.

References

Reference 1: https://psmv5.blogspot.com/2023/12/cheese.html.

Reference 2: https://www.dulwichpicturegallery.org.uk/.

Reference 3: https://psmv5.blogspot.com/2023/12/wellingtonia-108.html.

Reference 4: https://en.wikipedia.org/wiki/LMS_Stanier_Class_5_4-6-0_5231.

Reference 5: https://en.wikipedia.org/wiki/Peter_Paul_Rubens. 1577-1640. Painter and diplomat. Presumably his workshop was more or less a factory, along the same lines as that operated some years previously by the Breughels.

Reference 6: https://sarashamma.art/.

Reference 7: https://en.wikipedia.org/wiki/College_of_God%27s_Gift.

Reference 8: https://belairhouse.co.uk/.

Reference 9: https://psmv3.blogspot.com/2017/01/cheese.html.

Fake 169

The new timber false ceiling going into the Ashley Centre here at Epsom, to replace most or all of the existing false ceiling, suspended white foam tile variety.

Presumably some made to measure chipboard or fibreboard, cunningly coated with brown wood grain effect. I did have a moment of doubt, was the timber for real after all? But I think I am convinced by the zoom above that it is not.

Still no firm news about who is going to take the slot vacated by the House of Fraser. Beyond it seeming unlikely that it will be a store of that sort: Epsom is no longer big enough to carry such a place. Or, it seems, to carry a proper gents outfitter, like the Lester Bowden of old, which survives in name only, this despite Epsom being a serious commuter town. A proper gents outfitter where a German suit might cost you two or three times what you might otherwise pay in M&S. I still have a fine racing jacket from them, in candy-stripe seersucker. A jacket which still gets the occasional outing. As it happens, cheap too.

References

Reference 1: https://psmv5.blogspot.com/2023/12/fake-168.html.

Reference 2: https://en.wikipedia.org/wiki/The_Ashley_Centre. Opened by no less a personality than our late Queen, back in 1984. In October, so she did not wrap the opening into her annual visit to the Derby up on the Downs.

Group search key: fakesk.

Trolley 603

Bit of a stretch to score this trolley which was inside the Ashley Centre. But it was an M&S trolley parked right outside Waitrose, so I decided that it fell within the rules. Probably to be the last trolley before the festive break.

Handle locks (top right) seem to have come back into use, after a period of absence, perhaps older trolleys pulled out of retirement for the festive rush. So I must resume carrying either pound coins or tokens again.

PS: this being another post with an improper file name. But a simple clerical error rather than one of the senior moments which made their appearance in the last post.

References

Reference 1: https://psmv5.blogspot.com/2023/12/trolleys-601-and-602.html.

Group search key: trolleysk.

Senior moments

Batch No.704 started off well enough. There was a little wholemeal left in the bag (some weeks past its best-before date), so I added that to the mix, topping up the white flour, water and yeast proportionately. This last also taking into account the age of the yeast suggesting that a little more power was needed. All this took the weight of dough up from the normal 5lbs 13oz to all of 6lbs 6oz.

It took its two rises in the usual way, then was popped into the oven at around 15:50. A little later, I thought it looked a bit dark. Then a bit later still, I thought it looked very dark. At which point I realised that I had set the oven to 250°C rather than 200°C, rather a big difference. Much brain work about how to adjust the temperature and cooking time in consequence. With the first move being to cut the temperature to 175°C while I thought about it.

In the end, in the knowledge that bread seems to be quite tolerant of overcooking, I cut the cooking time from 50 minutes to 40 minutes, with half the result snapped above.

Cooled, it tasted fine. No hint of charcoal about the crust either - which, to be fair, was about the colour of the crust of the rustic I buy from Olivier. Perhaps real bakers cook at a higher temperature than I do. Just a hint of settlement at the bottom of the loaf visible right. 

Part of this lower temperature being that I am a bit uncomfortable about cranking our domestic fan oven up to 250°C, right at the top of its range. The oven elements are quite dear to replace, what with call out charges and one thing and another. For which see reference 1 for the last time.

In any event, the first time I have had this particular lapse.

However, it was compounded by the game of Scrabble which took place in the margins, during which I was very conscious of various lapses of word arithmetic. I kept thinking I could place such and such a word in such and such a place, but having made some elementary mistake. Like thinking I had two 'a's when I only had one. Or shifting a consonant to one of its relatives. Or converting the desire to have some particular letter to actually having it. Or focusing on one of the words involved to the exclusion of another. With the word that I was thinking of turning out on inspection, when the tiles were half down, not quite to work. Very much the sort of thing turned up by Warren and others a long time ago and mentioned quite recently at reference 2.

All stuff which is grist to the brain's mill, but stuff which is supposed to be sorted out under the covers, without reaching consciousness or otherwise attracting attention.

Hopefully things will not get worse too quickly.

References

Reference 1: https://psmv5.blogspot.com/2022/03/zanussi-rules-again.html.

Reference 2: https://psmv5.blogspot.com/2023/12/silent-consciousness.html.