What an awful winter
This week: What an awful winter; Complex statistical analysis;
Last week I said that I thought that we would have another unsettled week this week and we have.
We have received a total of 60 mm / 60 lt/m² of rain just this week, which has taken us nicely above the average for our winter months.
While the rain was falling outside, I was finishing the latest Police History Magazine. I doesn’t seem as though it was three months since the last one.
Going up the hill behind my home on Saturday morning, the first sunny morning we have had, I needed wellingtons and still had wet knees from the dew on the weeds.
Only one feline followed, complaining loudly about getting wet, until he could get onto the old stone walls.
It was worth the walk just to see the carpet of wild flowers everywhere. The yellow flowers are Perennial Wall Rocket, Diplotaxis tenuifolia, loved by butterflies because of their high nectar content.
The Wild Rocket is everywhere at the moment and from a distance it looks like Mustard flowers.
Large numbers of wild Cyclamen, Cyclamen repandum, were in flower.
The Horseshoe Vetch, Hippocrepus comosa, was resplendent in the morning sunshine.
In my orchards the Sow Thistles, Sonchus asper, are in flower and will need cutting once they set seed, otherwise I will have hundreds more next year.
The cool wet weather has really favoured all the weeds though. Small paths are completely overgrown and in the olive groves, the grasses are now more than a metre tall.
The wild Euphorbia helioscopia are looking very healthy.
In fact everything is a bright, verdant green. We may be at the start of astronomical spring now (20th March) but here in Dol, we are well on the way towards summer.
What an awful winter
After yet another grey, wet and miserable week, I have to say that I am fed up and can’t wait for our usual good weather to return.
The Mediterranean winter begins at the start of November and finishes on the 31st March each year, a total of 20 weeks.
However because both September and October last year were cooler and wetter than usual, it feels as though we have had six months of cool, damp, grey and generally miserable weather.
Cool and damp are of course relative terms. We don’t get air frosts here in Dol, just occasional radiation frosts on the ground which don’t in of themselves cause problems to most tender plants.
The 11 day average temperature is what is important for growers and horticulturists. A single cold night will not really affect the 11 day average but several cold nights and cold days will.
One of the things which my weather station records is the amount of sunshine and the strength of the ultraviolet radiation we receive.
UV radiation affects the rate of plant growth and development, hence why some greenhouses use UV growlights to kickstart plant growth on dark, winter days.
Too much can be bad for plants (and definately for humans) so having an idea of the daily UV value is useful.
What is of more interest to me at the moment though is the amount of actual sunlight we receive.
My perception is that this winter, especially the first three months of the year, have been way down on the average for “nice days”.
How do I define a “nice day”? It is a day when the sun shines and I generally feel motivated to really crack on with work in the orchards.
When it rains, when the grass is soaking wet, when the soil is too heavy to dig, when it is cool or there is a cold wind, I just don’t feel like wrapping up well and going out. It is much easier to do work on the computer, and I always have plenty of that to do.
Even the polytunnel is uncomfortable on cold damp days, as the condensation falling from the roof inside drips down your neck.
Complex statistical analysis
All my weather station data is uploaded to various international weather servers, every five minutes of every day.
This means that it can be used by national and international meteorologists when they are producing charts and forecasts.
It is also available to anyone, anywhere in the world who wants to know exactly what the weather is like here in Dol.
Complex charts are available too, but the one for the daily sunshine is not especially useful or user friendly.
It shows when the sun shone (or didn’t) and how strong the received radiation was per square metre and the UV level. But this does not really tell me what the last week was like, when compared to 2023 or 2024.
Downloading the raw data this week, as a spreadsheet file, I was stumped about how I could make sense of the thousands of lines of data I was presented with.
There are 288 data points for every 24 hour period, making 105,120 individual records for each standard year that need to be analysed.
Try as I might, I just cannot visualise this in any sensible way, so I asked in an online weather group for ideas. I was surprised when it was suggested that I use ChatGPT to both suggest ways of presentation and to even analyse the raw data.
Of course I know about ChatGPT, both the positive and the negative, but I have never used it and certainly never thought about asking it to solve this kind of problem.
I’m trying to think three dimensionally; what would I like the data to show so that it makes sense to the average reader?
It hasn’t kept me awake at night, but I have woken up and thought about the challenges.
Things like today, Saturday, where the morning was clear and cloudless then from lunchtime, clouds have rolled past. The UV index has varied between 7 and 1. Solar is the top chart with UV in blue. Rain is the bottom chart.
The atmosphere reflects light (which is why we see the sky as blue), and solar radiation, so my sensitive instrument records a gentle rise from 05:40 to 07:20 when the sun rises above the tree line. But those are not sunshine hours.
A spreadsheet will graph pretty much whatever you want. The problem is I don’t know what I want.
This is really a philosophical question so more thought will need to be put into this before next week. NCG