What is Stevenson’s Screen?

Stevenson’s Screen is a wooden box fitted into a steel frame, specially designed to protect weather instruments like thermometer, barometer, etc. from the sun’s rays and other natural heat radiation. British civil engineer Thomas Stevenson designed the first Stevenson’s Screen in 1818. In order to prevent direct sunlight falling on the instruments, it was designed so the door opens to the north in the northern hemisphere. It is painted white to reflect incoming radiation from the sun and is set at a height of 1.25 m above the ground, so as not to be affected by the earth’s low-level radiation.