The value of the Stefan-Boltzmann constant (σ) is 5.6704 x 10Converting to the more familiar Celcius and Fahrenheit temperature scales, we get:Based on this calculation, Earth's expected average global temperature is This calculation of the expected temperature can be done for other planets as well. To visualize this, imagine lighting a small closet with about 13 or 14 one hundred watt light bulbs. The planet will continue to warm until the outgoing infrared energy exactly balances the incoming energy from sunlight. the incident energy which is in the form of sunlight. To determine how much energy Earth absorbs from sunlight, we must multiply the energy intercepted (that we calculated above) times one minus the albedo value; since Now that we have a value for the energy flowing into the Earth system, let's calculate the energy flowing out.The Stefan-Boltzmann law tells us how much infrared energy Earth will emit The law of conservation of energy tells us that the energy emitted must be equal to the energy absorbed. Incident energy is known as irradiance or radiation flux (in Watt/meter

In this case, the circle's radius is simply the radius of Earth, which is about 6,371 km (3,959 miles) on average. Scientist refer to the amount of In order to calculate the total amount of energy arriving at Earth, we need to know how much area is being lit. The equation or formula of solar cell fill factor is as follows:©RF Wireless World 2012, RF & Wireless Vendors and Resources,

The area of a circle is pi times the radius of the circle squared.

Noting that pi times Earth's radius squared appears on both sides of the equation, we can use a little algebra to simplify the result:Earth's overall, average albedo is about 0.31 (or 31%).

Setting these two values equal, we can substitute in the expressions for each.

There is another important parameter which is used to determine solar cell performance. The specific value at Earth of The sunlight Earth absorbs heats our planet. If we multiply this area by the amount of energy per unit area - the solar "insolation" mentioned above, we can determine the total amount of energy intercepted by Earth:Plugging in values and solving for E, we find that our planet intercepts about 174 petawatts of sunlight... quite a lot of energy!Since Earth is not completely black, some of this energy is reflected away and not absorbed by our planet.

It turns out that oceans and atmospheres can have a big influence on a planet's temperature... we'll have more to say about that later.

Scientists call this balance "thermal equilibrium".

If you multiply KWhat do we mean by the "expected temperature" of a planet? It is provided by the World Bank Group as a free service to governments, developers and the general public, and allows users to quickly obtain data and carry out a simple electricity output calculation for any location covered by the solar resource database. That sunlight is absorbed by the planet's surface, heating the ground.

This solar irradiance calculator takes data collated over a 22 year period to provide monthly average irradiance figures.

The specific value at Earth of 1,361 W/m2 is called the "solar constant". As mentioned solar cell efficiency is the ratio of electrical output power (in Watt) to

Any object with a temperature above absolute zero emits electromagnetic (EM) radiation. The units are in solar flux units (1 sfu = 10-22.m-2.Hz-1). Based on observations of similar stars, astronomers think our Sun is brighter now than it was early in its lifetime. Enter latitude and longitude for the location of interest. Although this value varies slightly over time, it is usually very close to 1,361 watts of power per square meter. Above mentioned solar cell efficiency formula or equation is used for this calculator. We then multiply the area by the insolation (in units of energy flow per unit area) to find out the total amount of incoming energy.

A planet completely covered with snow or ice would have an albedo close to 100%, while a completely dark planet would have an albedo close to zero.

For now, lets look at the simple case of a planet without air or water. We then multiply the area by the insolation (in units of energy flow per unit area) to find out the total amount of incoming energy.It turns out that we can simplify our calculation of area by noticing that the amount of light intercepted by our spherical planet is exactly the same as the amount that would be blocked by a flat disk with the same diameter as Earth, as shown in the diagram below.energy from sunlight as "insolation".