Solar constants definition

What is solar constant?

The solar constant is the average amount of solar radiation received per square meter on a surface perpendicular to the Sun's rays outside Earth's atmosphere at the mean Earth–Sun distance (1 astronomical unit). Which is shown in the picture below:

Why is the solar constant important?

The solar constant is an important factor in understanding the Earth's climate and energy balance, as it influences the temperature of the planet and drives weather patterns. The solar constant is defined as the amount of solar radiation that is received at the top of the Earth's atmosphere on a surface that is perpendicular to the sun's rays.

Where is solar constant measured?

It is measured on a surface perpendicular to the rays, one astronomical unit (au) from the Sun (roughly the distance from the Sun to the Earth). The solar constant includes radiation over the entire electromagnetic spectrum.

What is a constant solar radiation?

The word 'constant' is a little misleading since, because of the earth's elliptical orbit the intensity of the solar radiation falling on the earth changes by about 7 per cent between January 1st, when the earth is nearest the sun, and July 3rd, when the earth is furthest from the sun.