Life in a Dol house
2016 - Week 34

Change is in the air

The days are becoming noticeably shorter. 

This week, the early sun no longer shines into my bedroom from sunrise. Around the summer solstice, as the sun rises over the low hills between Dol and Verbanj, the first rays creep into the room around 05:50 and stay until 07:20. Last week it was after 7am that a thin shaft of sunlight illuminated the bay window. This week nothing. The actual sunrise is of course much earlier, but being sheltered on three sides by hills, and being well tucked into the lea of the hills to the south, there is a lag between sunrise and the sun rising above our surroundings. 

The change in day length varies depending upon your latitude. Here in Dol, our day length is reducing by 2 minutes 45 seconds a day. In Newcastle upon Tyne, it is reducing by 4 minutes 15 seconds, and in Tasmania the day length is increasing by 2 minutes 30 seconds a day. As I write this in the early evening, the shadows cast by the trees on the wall are lengthening and the light on the wall outside is turning the limestone cream, rather than the bright white of full sun. By 18:30 the sun has gone for the day, although we still have another hour of daylight.

I was made aware of some local lore this week too. The start of the week was much cooler, creating a very pleasant temperature to work in. I was visiting friends and remarked on the change and they said, "Yes, of course, it is always cooler here after the 17 of Kolovoz". Very specific, but also quite accurate. 

It reminded me of the Al Droor almanac of the Arabian Gulf. In existence for 1,000 years, Al Droor uses stars to chart the seasons.

There are four seasons each with 100 days and one season, mid summer of 60 days. The Almanac then lists five lost days of violent and unpredictable weather. The autumn season, or Al Safri begins around the 17th of August. This accumulated and refined wisdom has been relied upon for centuries by the peoples of the Gulf and is still used today. 

In the years 46 BC Julius Caesar is credited with standardising earlier Roman and Greek based calendars into the Julian calendar, with years of 355 days, with extra days being added to the end of February to keep the calendar in line with the natural seasons. Is wasn't until 1582, more than 1,500 years later, that Pope Gregory created the modern Gregorian Calendar. It then took over 300 years for it to be fully adopted. The last country to change from the Julian to Gregorian calendar was Turkey in 1927. The UK and the Colonies together with some parts of the current USA didn't change until 1752. The year that we know today of 365 days and 366 in most 4th years is a modern invention to keep the annual equinox and solstice to within +/- 1 day of the same date each year, but it is the accumulated knowledge of centuries of working the land that is commonly used by people to sow, harvest and cultivate.

Climate change is likely to alter that, because almost everywhere is experiencing weather which is different from the "normal". This week I have made a start on building the Stevenson Screen for my weather station. Strictly and amateur observer, I have a Class 3 station. That is one where the various instruments record a number of different metrics, but the instruments are not calibrated and are not set to exactly measure.

Take the anemometer for example.
When I set it up, it was on the only available place, but being so close to the pitched roof, it is highly susceptible to vortices's and only when the wind is very light is it completely accurate.

Thomas Stevenson developed his standard for a small thermometer screen in 1864. This was then improved and the design, known as the Stevenson Screen became the accepted standard worldwide for weather instruments. Even today where there are many more highly accurate instruments, most weather stations still have a Stephenson Screen. Up on the promontory, close to St. Michael's Church here in Dol, there is the official Met service of Croatia station - with a Stevenson screen surrounded by olive trees.

The foundations and post holders were put into the citrus orchard last year, when my builder friend Cvjetko, had some spare concrete. I have had to design my own screen, because the plans which were once published by the Royal Meteorological Society of London, are no longer available online. It's not difficult though and the screen will have the required double louvre walls, double sloping roof, false floor (to reflect ground heat) and it is sited in an open position - but still close enough to the house to transmit the readings every five minutes by UHF radio to the base station receiver antenna. 

I made the four corner posts some time ago, and they have been primed, undercoated and finished with gloss paint. First job was to clamp them in their post holders then make sure they were vertical.

The next task was to accurately measure the distances between them. Unfortunately, one of the ground post holders is slightly out of position, and no matter how I tried to get all four sides equal, I couldn't. Eventually I settled for three corners being square and the fourth being offset on one side, which makes that side slightly longer. It's not the end of the world, but it is a lot easier than trying to dig out the concrete and reset the post holder. 

With all four posts vertical, I then measured and marked the height of the bottom of the screen on all the posts.

What I am aiming for is to upgrade my weather station to a Class 2 standard, which means that it uses the same instruments as before, but contained in an approved screen and with less interference from trees, buildings and roofs.. Class one is reserved for fully professional stations, costing many thousands, with a lot more instruments. The Croatian national station I mentioned earlier would not meet a Class One status, because of its protected location in an olive grove. 

With the measurements completed, I then drew a detailed plan from which I cut the four flat pieces from 10mm external plywood. This was again cut to reflect the slightly out of square shape then I let in the four corners with a jigsaw cutter.

I will use my table router to cut a rebate in each upright to accept the plywood pieces and also the double louvres. Everything will then be glued with Cascamite resin glue and painted before the screen is erected on the post holders.

I have continued to dismantle the walls of the old pig sty, at least as best I can. This was the wall at the start of the week.
One wall has been reinforced with 10cm of concrete and I will need the big breaking hammer to demolish it. 


Gentle dismantling is not going to be an option!

As noisy tools are banned until the 21st September, I will have to wait another three weeks for that, but I have other work that I can be doing - a lot of other work in fact.

As part of the preparations for the new Stevenson Screen, I dug out the soil temperature probe, which has been in place for 18 months. Digging out is not a good description, as I had to break up the clay soil with a lump hammer and chisel, before I could get the spade in.

I did mange to dig out between the concrete piles to a depth of 30 centimetres, then riddle the soil to remove all stones before replacing it and reburying the probe, 10 cm deep. This again highlights the differences, because a Class One station will have three soil probes, at depths of 5, 10 and 50 centimetres.

On Wednesday, my friends Željko the Architect and Cvjetko the builder came round for a site meeting.

After much discussion, it seems we have a way forward and have moved another step closer to actually starting to do the building work. We still need the plans and some paperwork from the local council, but otherwise it was a very positive outcome.

Željko is a rail enthusiast and owns a large scale ride on steam locomotive for garden railway use, although at the moment he does not have a track to run it on. It seemed appropriate to set up a small test track in the sunshine and get my Hornby Live Steam "Mallard" out for a run.

What started out as a morning meeting quickly ended up lasting well into the afternoon.

At the end of the week, the temperatures have been increasing again. 

From day time temperatures in the low twenties on Monday, to Friday and Saturday, when the temperature reached almost 31 degrees. So whereas outside work was pleasant at the start of the week, I have retreated inside again at the end. There are still lots of things to do, but I have been finishing my planning for the next month or so.

Some of the planning includes winter plantings. Insect pollinators are crucially important and I want to encourage as many as I can to come into the gardens and orchards. I have planted a number of plants and shrubs to encourage them, but for sheer spectacle, it would be hard to beat the Lantana Camara.

This shrub is an import to Europe from the Americas. It can be seen all around the island but there are two example on the lane leading up to my Dol house.

One is a pink variety,

the other an orange/red.

But from the moment the first flowers appear in late spring, until the cold nights stop growth, the flowers are a magnet for bees and butterflies. 

I am used to the Buddleja Davidii, a lanky shrub which, know in the UK as the "Butterfly bush" which has colonised the railway embankments all over the UK. It was once known as the "Bomb site plant" because of its ability to take over and thrive on broken masonry and destroyed buildings. It sets seed easily and is classed as an invasive species in the UK. Here the Lantana also propagates easily by seed, but this week one one near my gate, I counted more than 20 butterflies of 8 types all simultaneously feeding on the plant. There were numerous bees and hoverflies too, but also a Hummingbird hawkmoth, Macroglossum stellatarum, which required some persistence from me to photograph it.

Very wary of people, it barely stays still at a flower long enough to focus on it. 

It was too quick for the autofocus of my camera. Several of the beautiful swallowtail butterflies were present. There were several Scarce Swallowtail, Iphiclides podalirius.


Also the true Swallowtail,
the Papilio machaon.

Then there were the Painted ladies, Vanessa cardui


and Red Admirals.

And a couple that I cannot identify for certain.

This looks like a Wood white, Leptidea sinapis, with its distinctive rounded wings, but the way it's body is hanging down and the dark mark on the top of the forewing are not typical.

Callie brought me a big hawk moth this week.

Some 4 cm long and with distinctive zig zag markings, it looks similar to a Silver Y, Plusia gamma, but it has an eye on its shoulder and it had its head tucked under its body with distinctive black and yellow striped antenna and there is no prominent whit "Y" on the wings. I released it back into the garden, shaken but otherwise unharmed.

Whilst clearing some grass to put more of the reclaimed stone in the top orchard this week, I disturbed some Katydids. 

This is a Mediterranean Green Katydid, Phaneroptera nana.

Which when in amongst the weeds, has perfect camouflage.

Another perfectly camouflaged Katydid which I am still trying to identify is this sand coloured beauty, who has lost one of its jumping legs.
And with that, I am running out of time. 

It takes three times as long to manage the photographs, mark and identify them, reduce the size for the web and then insert them, as it does to actually write the script. So I will leave you with a picture of a Pearl Fritillary, Boloria euphrosyne in the orchard.

Norman