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 book The Weather Observer’s Handbook (published by Cambridge University Press), 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
Earth temperatures at 30 cm or deeper are measured using specially lagged thermometers hung on chains in steel tubes at the required depth, or using electrical sensors. Cabled sensors are ideally suited to measuring grass or earth temperatures, although care needs to be taken in how earth temperature sensors are exposed, as locating them in tubes with higher conductivity than the surrounding soil will introduce significant errors.
The wind is highly variable in both speed and direction, and obtaining good measurements of the wind poses particular challenges for instruments, logging equipment and site requirements.
By convention, 24 hour minimum temperatures read at the morning observation are entered to the day on which they were read, whereas 24 hour maximum temperature and total rainfall are entered to the day prior to the observation (they are said to be ‘thrown back’).
Grass temperatures should be sampled and logged at the same interval as used for air temperatures; for earth temperatures, particularly at depth, an hourly or even once-daily logging interval may be sufficient.
Most air temperature measurements are now made using resistance temperature devices (RTDs), which are steadily replacing liquid-in-glass thermometers. The main types of sensor in use today are the platinum resistance thermometer and the thermistor. The former is more accurate and more repeatable, but more expensive. Both can be made very small and thus highly responsive.