lec 5 energy and the atmosphere

in atmosphere, pressure changes

linearly

in atmosphere, temperature changes

irregularly (rises and falls depending on the layer

atmosphere is composed of

gases, clouds, dust, and microplastics

what interacts with incoming and outgoing radiation

gases, dust, clouds, and the surface

scattering

solar light collides with air, dust, and clouds, which deflect it in all directions

blue sky because

blue light is scattered most effectively as sun passes thru less atmosphere

at sunrise/set, sunlight passes thru more atmosphere, resulting in

more scattering of longer wavelengths → redder appearance

albedo

fraction/percentage of energy that is reflected by a surface rather than absorbed

lighter objects have

higher albedo (more reflection)

absorption

process where energy in form of EM radiation is absorbed by atmospheric substances or surface

absorption involves heat transfer by _

radiation

why doesn't earth continuously warm up if it keeps gaining energy

emission at a longer wavelength, in the infrared

selective absorbers

can be transparent to one wavelength while interacting with another

greenhouse gases

transparent to shortwave but absorb longwave; trap some heat the planet would otherwise emit to space

role of conduction in earth's heat

energy moves directly from ground to first mm of atmosphere

role of convection in earth's heat

warmer air from conduction then rises

latent heat transfer

energy used to vaporize liquid water into water vapor (energy released at later condensation

unequal solar distribution

energy is spread over a greater area closer to the poles

net energy deficit/surplus above/below

35 degrees latitude