|Stevenson Screen Installation|
Support post installation
Sensor located in the screen
Screen in position on the post
After I had noticed temperature variations between my equipment and other local weather stations, and following a conversation with my friend Nick from chepstowclimate.com, it was decided to locate the combined sensor from the weather station within a home made Stevenson Screen.
Temperature variation was most noticeable in the winter period, where my recorded minimums could be as much as +3 degrees C above that recorded by others.
My original positioning took no account of the amount of heat retained, and reflected, by the brick walls of our home. I had located the sensor in what I thought was permanent shade up under the eaves, on a north facing part of the building.
Nick very kindly put together the screen shown in the photographs on the left. The hardwood box, which has louvered ventilation slats, was given several coats of white undercoat paint, and finished off with a couple of coats of white exterior gloss.
We mounted a wooden fence post in a good concrete base. Ideally the screen should be located above grass, but as I have no lawn here, a small section of the 'boss's' garden was commandeered... The low growing ground cover plants should give the same effect as grass.
A trench was dug and some 1 inch diameter plastic water pipe buried, through which the sensor cable was pulled back to my radio room. Remember to feed some string through the pipe prior to burying, as this will enable the cable to be pulled through. The plastic pipe will afford the cable some protection from any gardening activities in the vicinity.
The final job was to mount the sensor at the Met Office recommended height of 1.25 meters.
Not quite the final job, as we had to 'make good' and put the garden back.....
Initial results are encouraging, and my thanks go to Nick for all of his help and hard work, which included crawling through my attic routing cables.