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How accurate should “accurate” be?

This week: Up the pole without a ladder; How accurate should “accurate” be?; Christmas lights; A happy feline; A new tool has been delivered; Winter continues;

Low winter sun
Low winter sun illuminates the distant Dinaric Alps

This week it is time for our annual expedition to the vets.

Every December, the felines need to have their yearly flu vaccination and parasite tablet. So on Monday morning, I put two of the young adults in one carrier and a third in the other transport box and off we went.

We were the first patients and were quickly in and out of the surgery without a murmur of complaint. Then it was off on a shopping trip to the supermarket and back home.

On Tuesday morning it was the same routine with Pongo the fourth young adult in one carrier and Callie in the other.

My second oldest feline Gizmo, at 4½ years, hates the carriers with a vengeance and I couldn’t get him into it.

I'm not getting into that carrier!
I’m not getting into that carrier!

I need a different strategy for next week.

Pongo cried from the moment we left home, until the moment we got back. Nothing the vet or I did would placate him. No scratching or fighting or anything, just plaintive cries for help, except no one was listening.

We have had more rain this week, over 65mm and some more even this afternoon, however as pressure is rising now, it looks as if the intensive period of six weeks of wet weather is over, at least for now.

I was asked if this is now the new normal: Ten months of drought and two of flood!

I really have no idea…

Up the pole without a ladder

As well as visiting the vet’s clinic, I also called at Volat to get some small pieces of hardware for the new weather station installation.

The combined height of the two poles is almost six meters and whilst the bottom pole is firmly attached to my Stevenson Screen, the top pole needed wire support stays.

The three support wires are to keep the sensor unit steady at the top of the pole.

Top of the pole weather sensors
Top of the pole weather sensors

I did need to drill into some substantial rocks to fix the anchor points and then I used a Hook Eye Turnbuckle at each ground point.

The guy wires were attached to the pole with a thimble and wire rope clip and I then lifted the pole and dropped it over the bottom section.

A frangible engineering solution
A frangible engineering solution

There was only the slightest amount of play, so my engineering design solution had worked.

Finally I adjusted each guy wire to get the pole close to vertical, before fixing the wire to the turnbuckles using more thimbles and wire rope clips.

Ground anchor and turnbuckle
Ground anchor and turnbuckle

I had my long spirit level out, with the intention of checking the upper pole for being true, but in the end I didn’t use it.

With just a few rotations of two turnbuckles, the wires became taught.

Walking around I could see that the pole was now vertical and held in position.

I decided that my eye was a good enough judge so put the spirit level away again.

There is a tiny spirit level on the top of the sensor unit, to help make sure it is horizontal.

I did consider getting the drone out for a short flight to see how accurate my eye was, but the downdraft would affect the anemometer, so I decided not to bother.

How accurate should “accurate” be?

I mentioned last week that the reason why I purchased the new weather station was because it was discounted for Black Friday and my existing system is 12 years old.

In terms of electronics, twelve years is a very long time, especially when all the sensors have been exposed daily to everything the weather can throw at them.

During the shakedown period, I have been looking closely at the two display units, which are mounted one above the other in the hall.

New display on top, old below
New display on top, old below

I have never had the opportunity to do a comparison to see how accurate the IROX (old) sensors were.

Class One weather stations, which are the Government Weather Service or University Meteorological stations have accuracy to 0.01 of a degree for temperature and similar fine tolerances for every other measurement. Their starting price is usually around €45,000 too.

I had wondered about my old digital rain gauge, after a neighbour 50 meters away told me that his plastic rain gauge always gave a much higher precipitation reading then my digital one.

With the rain this week, and with other measurements, I have found that there is a discrepancy of 0.5mm for rainfall. However that could be accounted for by the proximity of trees to the old gauge.

That half millimetre was not apparent during every rainfall event. Several times this week they have recorded exactly the same amount of precipitation.

The temperatures also seem to be occasionally slightly different, but only by 0.2 of a degree Celsius. Granted this is ten times the accuracy required of a class one station.

However when you have heard a radio or TV weather forecast, when were you told that “Tomorrow would be 5.3ºC or 5.5ºC “, and would it matter?

So a variation of one or two tenths of a degree, for me and my users is really not important. The question is, “How accurate is ‘accurate’? and does it matter”?

With the sensors firmly mounted at the top of their pole, I have logged the sensors on-line and they are now reporting to various meteorological organisations, feeding data into their huge computer models.

For locals, who want to know whether they can pick, plant or prune next week, both the old and new stations are online and available.

To see the what my new station is recording now, this minute, click on the picture below. For a ten day forecast, use this link: https://link.hvar-digital.com/Dol2prog

Weather stations in the vicinity
Weather stations in the vicinity

One of the additional sensors I now have is to detect and report lightning strikes.

Lightning detector
Lightning detector

Christmas lights

Rummaging through a box of light fittings, I came across a new packet of outdoor Christmas LED lights. I have no idea when I bought them, but they are marked in Croatian so it was sometime in the past seven years…

Although I am witnessing a change in Christmas here, as displays appear in shops a little earlier each year (now in mid November) and the displays are slightly larger each year, there are still few outdoor lights and decorations.

Looking outside last night, there were no coloured lights visible anywhere in the village and our single pendant light, at the cross roads, has not even been hung up yet.

Down in Stari Grad on Tuesday, the Christmas tree in the main square was on its side, following delivery and was waiting for the Men from the Municipality, to come along and make it vertical once again.

That wasn’t going to happen on Tuesday though, because the sea kept coming over the harbour wall, flooding the square and the streets around about.

I’ve just had a look at the town digital notice board. There is no mention of when the town’s lights will be turned on.

So from these comments of mine you will gather that Christmas here is still rather low key.

With a string of new lights and some empty space, it seemed appropriate for me to put them to use.

First of all I had to install a power supply. The terrace will become the sitting room, so at the moment, there is no electrical supply.

I do have an outside socket, suitably protected at the electrical Consumer Unit, so I ran a lead from it to new outdoor socket and fixed the socket to the wall of the old building.

Two wooden fence posts were repurposed, lashed to the reinforced steel uprights, which will eventually be part of my new building. At three meters apart, the uprights were exactly the right distance apart.

My last task was to plug the lights in, to make sure they worked, before stringing them between the two posts.

Coloured Christmas lights
Coloured Christmas lights

I have added a small timer so they come on at sunset, which is 16:20 at this time of year and go off at 21:30.

As they are the only lights on show, so far, I think they look really nice, even in the pouring rain.

Reflections in a rain puddle
Reflections in a rain puddle

A happy feline

My photo last week of my unhappy senior Cat Callie, tucked up in the corner of the log basket, next to the wood stove has resonated with several blog readers.

Fireside basket
Fireside basket

On a wet Wednesday morning I was in Jelsa and met a friend for a coffee and catch-up. I was presented with a new and smaller log basket as a present.

Callie likes sleeping on fluffy towels, so on the way home I stopped at the supermarket and bought her a new one.

With the wood stove lit, the big log basked moved and the new basket installed as close as is comfortably possible to the fire, Callie had a quick sniff (my friend has dogs) and then climbed in.

New basket -made to fit
New basket -made to fit

She likes the compact size, so thank you for the kind thought. Callie appreciated it!

A new tool has been delivered

As unseasonably warm weather continues, I have not been too worried about the Polytunnel project, which remains only partially completed.

Because I started the project before the rains came, the soil was as dry as everywhere else. The wind has now blown rain inside and the soil is nice and moist

Normally the two coldest weeks of the year here are the week after Christmas and the first week of January.

Part of the rationale for the Polytunnel was to protect my Banana, Mango and Guava and hope that with a little less seasonal cold, I may encourage heavy fruiting.

However the mild autumn, and it has been 17ºC again this week, has given me time to do some other things.

Regular readers will remember that I was trying to locate the correct aluminium extrusion fasteners for the polycarbonate roof.

Aluminium extrusion fittings
Aluminium extrusion fittings

I have given up on the search. Even after going to Split, I simply can’t find any here.

However the drawing gave me an idea, so I have developed my own solution.

I have bought strip wood and will use that as a base for the plastic “H” channel that I already have.

H Profile joint strip
H Profile joint strip

The wood, not as thick as in the photo above, will then be let into the wooden beams and the “H” strip will be bolted to the wood. This will provide the fixed and strong anchor I need to hold everything is place.

I will also add two extra support beams as well. However I realised that I would need to cut a rebate into the existing beams, to take the strip wood.

I could remove all the beams and use a router to cut the rebate, or I could try and cut the rebate with everything in place.

Casting around for a solution, I came across a new BOSCH tool, called a Palm Router.

This wood working tool is a single hand operated machine, using smaller cutting bits and because of its compact size, it can be used in confined spaces.

The machine was delivered this week.

BOSCH Palm Router
BOSCH Palm Router

In addition, an order I placed for some more stainless steel fittings from China was delivered on Thursday.

This means that I now have everything ready to finally finish the Polytunnel project.

Looking at the weather forecast, next week will be fine, dry, sunny and not cold, so it looks as though I have the ideal opportunity to finish my project, ready for any January cold weather.

Winter continues

I say “Winter continues”, but in all honesty, we have had no cold weather.

True, I have had the central heating on for comfort, but only for two or three hours in the evening. So far I have not used the electric blanket on the bed once.

This past week we have been five degrees above the seasonal average.

Winter temperatures this week
Winter temperatures this week

In the garden I have Hyacinth bulbs whose leaves are 10 cm tall.

Hyacinth leaves
Hyacinth leaves

The Narcissi which had just a couple of flowers two weeks ago are now fully in bloom.

Narcissi flowers
Narcissi flowers

I have even seen Hummingbird Hawk Moths flying and collecting nectar from my Lantana this week. They are usually hibernating until early March.

Hummingbird Hawk Moth
Hummingbird Hawk Moth

All this is taking place whilst the sun is barely above the hills to the south of my home for four hours each morning.

The low winter sun
The low winter sun

The good news is that Wednesday is the northern Winter Solstice, so from Thursday the day length begins to increase again.

We may not notice the change for a few weeks, but Spring is definitely on the way in this part of the word. NCG

2 Responses

  1. Jenny Crook

    Hello Norman,

    Since I have just emailed Christmas Greetings to the rest of our Woollons cousins, I didn’t want to leave you out.

    Thanks for the weekly blogs – I find them so interesting, like your weather observations, as well as the themes which run through them so we can see your progress with various projects in your property and garden.

    You never mention any interest in football but maybe your community will tell you about Croatia’s success against Morocco today!

    Finally, did you try a tempting treat to persuade Gizmo into the loathesome cat carrier? Good luck with that next week.

    Best wishes, your cousin Jenny

  2. Marcy

    Norman, absolutely love following your progress on your hothouse. So interesting. And the new weather vein is incredible.

    You always make the week brighter with you blog and wonderful photos. I bet with the narcissus blooming it all smells so wonderful.

    Wishing you a very Merry Christmas. Marcy