1 / 7

Solar constant

Solar constant. The solar constant is the amount of incoming solar radiation per unit area, measured on the outer surface of Earth's atmosphere, in a plane perpendicular to the rays. Solar constant for Earth, S = 1350 W/m 2. Albedo.

muriel
Télécharger la présentation

Solar constant

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Solar constant The solar constant is the amount of incoming solar radiation per unit area, measured on the outer surface of Earth's atmosphere, in a plane perpendicular to the rays. • Solar constant for Earth, S = 1350 W/m2

  2. Albedo Albedo is the fraction of sunlight which is reflected off a planet. When an object reflects most of the light that hits it, it looks bright and it has a high albedo.  When an object absorbs most of the light that hits it, it looks dark.   Dark objects have low albedo. .

  3. Earth’s Albedo • The average albedo of the Earth is about 0.30. • That means that about a third of the solar energy that gets to Earth is reflected out to space and about two thirds is absorbed

  4. One layer model Assumptions: No atmosphere

  5. Energy Balance Pin = Pout Pin = (1-A) S π RE2 Pout = σ TE4 4π RE2 (1-A) S = σ TE4 4

  6. Energy Balance of the One layer model Solar radiation Earth Earth’s infrared radiation to space σT4E (1-A) S 4 Tearth = 257 K = -16° C = 3.2°F

  7. Calculating Surface Temperature of the Earth σ T4 = S x ( 1- A) 4 Where S - Solar constant σ – Stephan constant - 5.67 x 10-8 W/m2K4 A - Albedo

More Related