Sunshine

Sunshine is the term used to describe the number of hours the sun is reflected and seen in the sky. It can also be referred to as insolation.

Insolation is the amount of solar radiation that reaches the Earth’s surface or atmosphere. It’s the primary source of energyEnergy is the ability to do work. Energy exists in several forms such as heat, kinetic or mechanical energy, light, potential energy, and electrical energy. Units of Energy: The SI unit... More for most physical and biological processes on Earth.

The length of the daylight and obstructions in the sky (visibility) are the two major factors that determine insolation (sunshine).

Measurement of Sunshine:

Sunshine Recorder, also known as Campbell-Stokes Recorder is the instrument used to measure the number of hours and minutes of sunshine in a place.

Sunshine Recorder is a glass sphere which is partially surrounded by a metal frame. On the inside of the metal frame is a sensitized card. The sensitized card is graduated in hours and minutes.

When the sun shines, the glass sphere concentrates (focuses) the sun’s rays onto the sensitized card and the rays burn a trace on the card; this continues as the sun moves across the sky.

The tracing can only happen when the sun is shining, in which the trace turns into hours and minutes. Eventually, the total amount of sunshine for the day is then represented on the sensitized card. The card is then taken out for that day.