Atmospheric aerosol Flashcards
What is the earths climate controlled by
The earths climate is controlled by the amount of solar radiation intercepted by the planet and the fraction of that energy that is absorbed
What is fundamental in determining how warm or cool the planet is
The balance between energy absorbed by the earth and energy reflectance tex back into space
Define solar flux / solar constant
The average solar electromagnetic radiation (total solar irradiance) per unit area is a flux density
What is the average value of the solar constant
The average value of the solar constant over space and time is 1368 W.m-2. This is not a
physical constant and is measured by satellites above the Earth’s atmosphere.
What is the albedo
Of the incoming solar radiation the fraction that is reflected back to space is called the albedo
What can albedo range between
Albedo can range between 0 (no reflectance) and 1 (complete
reflectance—like a perfect mirror)
What is the earths albedo know as and denoted as
The Earth’s albedo (also known as planetary albedo or average
planetary reflectance) is denoted here as 𝛼𝑝, known to be 0.31
What contributes to the planetary albedo
Clouds and scattering by air molecules
What is a black body
A black body is a theoretical concept useful in estimating
the maximum absorption and emission of a surface.
What does the black body emissive power depend on
Surface temperature
What is the stefan Boltzmann law
The Stefan-Boltzmann law (𝐹𝐵 = 𝜎𝑇^4) gives the total emissive power of a blackbody
in units of W.m-2
Define greenhouse effect
the heating of the Earth’s near-surface atmosphere by the trapping of out-going infrared radiation by
atmospheric gases.
Define global warming
the increase of the near-surface average global
temperature
Define radiative forcing
describes the net energy in units of W.m-2 made available to the Earth associated with the increase in the
concentration of each greenhouse
gas, since 1750.
