Geography: Climate/vegetation study Guide 1
things to know:
● Solar energy: from sun to earth
○ Distance and dimensions
○ Be able to calculate top of atmosphere solar radiation based on earth-sun distance
E(top of atmosphere)=Energy(sun)/area of sphere(4 π R ^2)
● Notes that R is the radius of a sphere defined by our distance from the sun.
● Solar energy: from equator to poles If you want to learn more check out Who developed the cognitive theory of depression?
○ Be able to describe the mechanism that causes uneven distribution of solar energy.
■ Lambert's cosine law of illumination:E= E(initial)X cosθ
■ Tropics receive more concentrated isolation due to earth’s curvature. 2.5 × more than the poles.
● The seasons: Be able to list 4 reasons why we experience seasonality in solar radiation. ○ Revolution
■ Earth revolves around sun, takes one year, at a speed of
■ Earth rotates on a axis once every 24 hours. Rotational velocity at Don't forget about the age old question of What are the four roles in organizational change?
equator is 1,674km (1,041mph).
○ Tilt of Earth’s axis
■ Axis is Tilted 23.5 from plane of ecliptic. °
○ Axis parallelism
■ Axis maintains alignment during orbit around sun.
● Annual march of the seasons
○ Winter solstice:december 21 or 22
■ Subsolar point at tropic of capricorn
■ Antarctic circle has 24 hours daylight
If you want to learn more check out How do you calculate the accounting rate of return?
○ Spring equinox: March 20 or 21
■ Subsolar point equator
○ Summer solstice: June 20 or 21
■ Subsolar point tropic of cancer
■ Arctic circle has 24 hours of daylight
○ Fall equinox: september 22 or 23
■ Subsolar point equator
We also discuss several other topics like What gives the stripe appearance of the pyramids?
Things to know:
● Electromagnetic spectrum:
○ Be able to describe relationship between object temperature and the magnitude and wavelength of emitted energy.
■ Hotter objects emit more energy, they also have a peak emission at
■ Planck's law:
● Atmosphere extends 32,000km(20,000mi) from the surface.
● Thermosphere is at 480 km (300mi)- top of principle atmosphere.
● Atmospheric composition:
○ Be able to list the constituents of the layers of the atmosphere
■ Heterosphere: outer atmosphere
■ 80km(50mi) outward, to thermosphere.
■ Homosphere: inner atmosphere
■ Surface to 80km(50mi)
■ Gases evenly blended.
● Atmospheric temperature: We also discuss several other topics like Name the different properties of life.
○ Be able to list the temperatures of the layers of the atmosphere
■ Thermosphere:roughly same as heterosphere
■ 80km(50mi) outward
■ Mesosphere:50t o 80km (30 to 50mi)
■ Stratosphere: 18 to 50km (11 to 31mi)
■ Troposphere: surface to 18 km (11mi)
■ 90% mass of atmosphere
○ Normal lapse rate: average cooling at 6.4C /Km (3.5F ) ° 1000ft °/
○ Lapse rate is defined as the rate of decrease with height for an atmospheric variable.( mostly applied to earth's atmospheres, but it can be applied to any gravitationally supported ball of gas.
● Atmospheric function
○ Be able to describe the function of the different layers of the atmosphere with respect to absorption of gamma rays, cosmic rays, x-rays, and ultraviolet rays. ○ Ionosphere
■ Absorbs cosmic rays, gamma rays, X--rays, and some UV rays.
■ Part of stratosphere
■ Ozone (O3) absorbs UV energy and converts it to heat energy.
● Anthropogenic pollution
○ Carbon monoxide
○ Photochemical smog
○ Industrial smog and sulfur oxides
Things to Know
● Three interactions between energy and the atmosphere: reflection, transmission, absorption
○ Reflection: scattering energy back out to space.(light reflects off clouds) ○ Transmission:scattering energy through atmosphere or water without transformation ( no changes in wavelength as energy passses through medium). ■ Refraction: change in speed and direction of light. Don't forget about the age old question of What are the advantages and disadvantages of using electronic medical records?
○ Absorption: assimilation of energy by molecules and conversion to different wavelength. (ex: solar radiation is shortwave radiation absorbed by atmosphere and the atmosphere emits energy as longwave.
● Transmission; be able to mathematically illustrate why the sky is blue from light scattering principles.
○ Shorter wavelengths scatter more than longer wavelengths and blue is the shortest wavelength which is why the sky is blue.
○ Scattering = 1/ wavelength^4
○ ● Transmission and refraction: be able to describe why refraction occurs and how it dictates the angle and distance light travels through the atmosphere.
○ The energy of the sun is projected on earth at an angle, thus refraction in the atmosphere will change the distance energy travels through the atmosphere ● Be able to describe the relationship between absorption and the distance traveled through the atmosphere(Beer's law- if light travels further more is absorbed). ○ Absorption can be described as the extinction of light as it paasses through a medium. The amount of extinction varies with distance traveled.
Surface energy balance
● Be able to describe terms in the surface energy balance
○ Radiant fluxes: shortwave radiation and longwave radiation.
○ Turbulent fluxes: Latent heat flux (evaporation and any phases change of water) and sensible heat flux (heating surface). Both driven by wind
○ Radiative fluxes=Turbulent fluxes or Rnet − G = H + LE (H= sensible heat flux, LE= latent heat flux)
○ Net radiation= S ↓− S ↑+ L ↓− L ↑
● Be able to calculate outgoing longwave radiation using the stefan-Boltzmann equation ○ Emissivity of a material is the relative ability of its surface to emit heat by radiation.
○ Equation: L = εσT4
○ Earth surface emits long wave radiation as a function of the surface temperature and emissivity.
● Be able to describe controls on latent heat fluxes
○ Driven by difference in vapor pressure between surface and atmosphere. ○ Evaporation: energy directed away from the surface.
○ Condensation: energy towards surface, water gets warmer.
● Be able to describe controls on sensible heat fluxes
○ Driven by difference in temperature between surface and atmosphere. ○ Conduction: exchange of heat between surface and atmosphere. Transferring heat from warmer to cooler materials.
○ Convection: transfer of heat associated with vertical air movement. As surface warms overlying air, air will rise and transfer heat.
● Be able to describe how available energy (from net radiation) is partitioned into sensible and latent heat fluxes.
○ If surface moisture is limiting then we can not expand energy to evaporate water and LE( latent heat) will be low. As a result we heat the surface and H( sensible heat ) is high.
○ Sensible heathas todowithheatingofthe surfaceand latentheathas todowith the phase changeofwater.