This site provides useful practical information related to global and national weather observing practices and instruments, including independent equipment reviews.
You will find much of the background in my new book The Weather Observer’s Handbook (Cambridge University Press, 2012), details of which can also be found on this site, together with useful links and downloads.
Author, The Weather Observer’s Handbook
A nation obsessed with the weather? Yes, certainly, but which nation?
Tip of The Day
Terminal hours based around ‘day maximum’ and ‘night minimum’ temperatures (where the extremes span only 12 hour periods) will generally give results which are incompatible with ‘24 hour’ sites, particularly in temperate latitudes in the winter months.
‘Humidity’ refers to the amount of water vapour in the air, a vital component of the weather machine. Various measures are used to quantify the amount of atmospheric water vapour – relative humidity and dew point being the two most commonly used. Knowledge of any two values can derive other humidity parameters. The amount of water vapour that the air can hold varies significantly with temperature – saturated air at 0 °C holds only a quarter of the amount that saturated air at 20 °C can hold.
The choice of datalogger and automatic weather station (AWS) software is crucial to the effective operation of any AWS. Its specification will define the capabilities (or limitations) of the AWS, and the choice of unit should be given at least as much consideration as the choice of sensors.
Generally speaking, the best exposure to the wind will be obtained by exposing both anemometer and wind vane in as open a position as possible, as high as possible, commensurate with both safety and accessibility for installation and maintenance. The necessarily elevated exposure will increase the vulnerability of the instruments to extreme weather conditions, particularly snow or ice, lightning and of course high winds. Great care should be taken in installation and cabling to minimize the potential for subsequent weather-related reliability issues.
Site and exposure. Site refers to ‘the area or enclosure where the instruments are exposed’, while exposure refers to ‘the manner in which the sensor or sensor housing is exposed to the weather element it is measuring’.