Tuesday, 10 January 2023
Sunday, 8 January 2023
Sunday, 1 January 2023
"A STONEHENGE mystery has been solved, according to an expert, after a "smoking gun" discovery was made to provide the "missing piece" of the puzzle.
Wednesday, 28 December 2022
The National Trust has warned that this year’s tumultuous weather is set to become the new ‘norm’ https://www.nationaltrust.org.uk/services/media/weather-and-wildlife-2022 The Stonehenge and Avebury WHS are thought to be at risk from climate change, so it is of interest here - http://www.stonehengeandaveburywhs.org/assets/Climate-Change-RA-for-web.pdf
We hear a lot about climate breakdown, that our climate is getting more unpredictable and tumultuous. We can survive and thrive in nearly any climate if we can plan and prepare for it from the arctic to the equator, from deserts to rainforests. But instability and uncertainty is dangerous. So is it getting more disorderly?
To check if any increasing instability was evident in England I thought a simple, quick and dirty way would be to compare the annual, and each season’s, temperature and rainfall using the long running Hadley Centre Central England Temperature (HadCET) dataset and HadUKP, the UK regional precipitation series available from https://www.metoffice.gov.uk/hadobs/index.html
My method was to compare the differences between years.
For instance the mean spring temperature in 2020 was 9.9°C, in 2021 8°C, and 2022 10.1° so the differences are -1.9°C and 2.1°C. I charted out the differences from 1963.
Wow, the swings are getting larger. English spring temperatures are getting less predictable.
So, I looked at more of the data.
Here’s the mean spring temperatures from 1904 – 1963:
Huh? That looks the same as the 1963 – 2022 chart. Let’s overlay them to see:
So, spring temperature got more unpredictable from 1904 to 1963 and then the pattern repeated from 1964 to now.
What is going on? I don’t know but whatever it is it isn’t unprecedented.
Just eyeballing the rest of the data graphs for the other seasons, years and annually I couldn’t spot any other repeating patterns either for temperature or rainfall. But torturing it with statistical analysis may reveal more. I hope someone with the skills does so.
Another surprise to me from the series is how related the Min and Max series are. It appears that the temperature band is narrow, is it self-regulating? A plot of spring temperatures shows:
A simple plot of Maximum temperature minus Minimum shows this over the whole period:
Sometimes very simple analysis is all that is needed to answer a question.
Friday, 23 December 2022
Wednesday, 21 December 2022
It seems surprising that the number of entrances that Durrington Walls originally had is uncertain.
1, 2, 4 and even 3 have been suggested.
Saturday, 3 December 2022
The route that the great sarsens were brought from the Marlborough Downs to Stonehenge is still debated. This blog was started to investigate it and it is still of interest.
I am using 40 tonnes as the maximum weight of an untrimmed sarsen that was moved. The raft or sledge it was moved on then adds to this weight.
The idea that they were brought down the River Avon from Upavon to Amesbury is still popular despite the impossibility of it.
The River Avon we see now isn't the same as it was in Neolithic times, the main difference is that it has historically been dredged, over-widened and impounded in many places due to past river management.
It would have been a multichannel meandering stream in a marshy valley bottom with trees and bushes growing over and in it.
1) They weren't slid on the frozen river.
The River Avon is largely fed from ground water along its route, water that is referred to as warm during the winter as it stays at near constant temperature all year round. The river doesn't freeze solid and according to Gold's Formula the ice would need to be over 500mm thick
The River at Amesbury has a normal maximum depth of 700mm and is usually half of that, and at Upavon it is a lot less.
2) They weren't loaded onto rafts and floated down.
To float 40 tonnes of stone 40 cubic metres of water must be displaced. If we had a weightless box to load the stone on it would need to be 4 metres wide, 20 metres long and 500mm deep, the depth of the river being a limiting factor here.
A wooden raft made of logs would need to be much larger. Wood has a specific gravity of 500 - 800 kg per m3 . The photo shows how only half of a log raft is out of the water. At the lightest end the raft would need to weigh another forty tonnes to displace enough water, at a more realistic weight for hardwoods of 750kg/m3 it nearly 100 tonnes. A forty five meter by five meter wide raft at 500 mm deep. The river is not big enough.
Only by using hollowed logs or canoes could the weight and size of the raft be reduced but would they be strong enough for the massive stones?
Dragging heavy stones through an overgrown bog didn't happen, they went overland away from the river.