Planetary Energy Balance Flashcards
What is the simplest equation for the Earth’s surface temperature, assuming no atmosphere?
T^4_s = \frac{S(1-A)}{4 sigma}
What does sigma represent?
The Stefan-Boltzmann constant, applicable in blackbody emission.
What is the blackbody emission equation for an object of temperature T?
sigma T^4
What assumption is made when we consider energy balance per square metre?
Divides every term by 4.
What does epsilon denote?
The emissivity of an object (how much of a black body an object is when emitting radiation). Ranges from 0 to 1 as it is a proportion.
What is the Leaky Greenhouse model?
A uniform atmospheric slab describing the energy balance, from incoming radiation and outgoing from the surface and to the TOA
What are the longwave emission terms in the Leaky Greenhouse?
Incoming: S/4, and outgoing is SA/4. These pass wholly through the atmosphere.
How does longwave behave in the atmosphere?
The atmosphere is fairly transparent to longwave radiation.
What are the surface terms of emission for shortwave radiation in the Leaky Greenhouse Model?
Outgoing from surface: sigma T^4_s.
Incoming from atmosphere: epsilon sigma T^4_A.
What is the TOA terms from the shortwave radiation (from the atmospheric slab)
(1- epsilon) sigma T^4_s (from surface via atmosphere)
epsilon sigma T^4_A.
How does adding a hydrological cycle (turbulent fluxes) alter the energy balance equations?
It cools the surface and warms the atmosphere.
What is sensible heat flux?
Dry heat transport from upward air motion.
What is latent heat flux?
Upward heat flux from surface water evaporation, increasing the atmospheric temperatures and decreasing the surface’s.
