Campbell Recorder,Blake Larsen Recorder

1. Done by :Girish Raghunathan
(1459409)
SUNSHINE
RECORDING

2. SUNSHINE RECORER
• A sunshine recorder is a device that records the amount of sunshine
at a given location. The results provide information about the
weather and climate as well as the temperature of a geographical
area. This information is useful in meteorology, science, agriculture,
tourism, and other fields. It has also been called a heliograph.
• The popular types of sunshine recorder are :
1)Campbell-Stokes Recorder
2)Blake-Larsen Recorder

3. Campbell Stokes Recorder
• The Campbell–Stokes recorder (sometimes called a Stokes sphere)
is a kind of sunshine recorder. It was invented by John Francis
Campbell in 1853 and modified in 1879 by Sir George Gabriel Stokes.
The original design by Campbell consisted of a glass sphere set into
a wooden bowl with the sun burning a trace on the bowl
Fig. Campbell Recorder in 1853

4. Fig. Improved design of Campbell recorder by Sir George Stokes
• Stokes's refinement was to make the housing out of metal
and to have a card holder set behind the sphere.

5. Working
• The hours of bright sunshine are recorded by the rays of the sun
passing through the sphere, which undergo focus and burn a hole
through the card placed behind it. The card itself is calibrated so
that the hours and minutes of the day are measured across it. At
dawn and dusk, however, the sun will usually leave a scorch mark
rather than a burn and so the readings at those times of day are
somewhat difficult to read at times.

6. Fig. Sunshine record cards

7. Blake Larsen Recorder
Fig. Inventor Alan Blake with the recorder

8. Blake Larsen Recorder
Designed a few years ago , the Blake Larsen Sunshine Recorder is a
more sophisticated sunshine recorder that uses sensors to detect
solar radiation and record them.
The recorder unit and PC software produce a fully automated system
to measure the duration of bright sunlight from dawn to dusk.
The system will be very easy to integrate into WEB based weather
recording systems as the sun shine records are simple text files.
It will also produce sun shine reports including graphical presentation
to a central WEB server and all the installation sites will be available
worldwide using Google Earth .

9. Blake Larsen Recorder
The main advantages of this are :
The system can produce results which are far more accurate than,
the Campbell Stokes recorder which requires manual intervention
and skilled interpretation.
The typical application areas – besides amateur weather enthusiast
of course – could be:
1)Holiday resorts who wants to prove their claim of sunny days
2)Agriculture to establish figures for moisture evaporation which are
dependent on actual sun shine hours.
3)Feasibility of establishing solar energy – water heating and/or
photovoltaic panels.

10. Blake Larsen Recorder
Fig. Blake Larsen Recorder