Unit 2 Notes
Climate Notes
• Atmosphere
o Troposphere is bottom layer
§ Mostly concerned with climate
§ Holds majority of clouds
§ 75% of atmosphere’s mass
o Tropopause right above troposphere
o Stratosphere above
§ Typically, stratosphere is separate from troposphere
§ Sometimes, volcanos/thunderstorms/etc. can release material into
stratosphere
• Surface Heating of Earth
o Equator, sun strikes at perpendicular angle
§ High energy input
§ Energy from equator à poles
• High à low
o Poles, sun strikes at oblique angle
§ Low energy input
o Factors influencing surface heating
§ Angle of sunlight
§ Distance light travels through atmosphere
§ Albedo of surfaces
• Reflectance
• Climate exists only because Earth is spherical and has non-
uniform albedo (land vs. water)
• Black body has no albedo
o Tendency is to go towards equilibrium
§ Which would be destruction of gradient = death
§ Maintain high à low gradient by inputting energy
• Sun is the energy for Earth’s gradient
o Variation in Temperature by Latitude
§ Mean annual temperature increases at low elevation, mesic, continental
locations
• Mesic: moist climate
o Xeric is dry climate
§ Temperature is about the same for 0-20° latitude
• Closer to equator
• Hottest mean annual temperature
o Not elevated
o Mesic (moist)
o Continental
, • Clouds and rainfall keep temperature uniform across tropics
o Clouds have high albedo
o Without clouds, the temperature would be much hotter at
0° than 20°
o So deforestation in the tropics would exacerbate climate
change
§ No trees = no clouds = hotter
• Hadley cells and adiabatic heating
o ITCZ, intertropical convergence zone, is where sun heats
air
o Heat of vaporization released when water condenses
o Towards the edge of Hadley cells are hot, dry deserts
§ Aka subtropical deserts
§ Xeric climate
o Solar equator hits 23.5° above and below geographical
equator
§ Tropics of Cancer & Capricorn
• Cancer = north = summer
• Capricorn = south = winter
o Trade winds
§ Whatever the name is, is where the wind comes
from
§ Ex: southeast trade winds come from the southeast
and go northwest
• Ocean Currents
o Linked to atmospheric circulation
o Winds push surface water
§ Fetch: when wind is blowing water in a sustained direction
§ Wind creates currents
o Land acts as deflection of currents
§ So due to continental drift, currents can change
o Water keeps surrounding land at moderate climate
o Ocean currents redistribute heat
§ British Isles are warmer than other areas of the same latitude
§ For deserts (Atacama and Namib), cold Antarctic currents veer away from
the land
• Intensifies the dry effect
• Fog, not rain, is main water source
• Fog is from cold water running against warm land mass
o These currents also relate to distribution of animals
§ Organisms on islands could be isolated species that followed currents
o Clouds form in a way that we cannot model well
§ Cloud type and distribution change reflectance
, § Cirrus clouds allow sunlight in but traps infrared radiation coming out
• Can heat planet
• Stratospheric clouds
§ Increase in clouds = increase in rainfall
§ Lower albedo of Earth = intensified heating
• From heat trapped
• Also from sea level rise
• Equations
o Constants
§ 𝑤 = 2897µm*K
• Wein’s constant
§ 𝐼!" = 1350 w/m2
• Incoming solar insolation
§ 𝜎 = 5.57 ∗ 10#$ W/m2K
• Stefan-Boltzman constant
§ 𝛼%&'() = 0.3
• Albedo
+
o Wien’s Displacement Law: λ* = ,
§ Max wavelength = wien’s constant / temperature (Kelvin)
§ 𝑤 = 2897µm*K
§ Black body temperature is the model
• Perfectly emitting black body with no atmosphere
• This is what T is in Wien’s Displacement Law
§ λ*,./0 = 0.5µm at 5800K
• Larger = shorter wavelength
§ λ*,12345 = 11.4µm at 255K
• Temperature at top of the Earth’s atmosphere
o Stefan-Boltzman Law: 𝐼!" = 𝜀𝜎𝑇 6
§ Incoming solar insolation = emissivity * Stefan-Boltzman constant *
temperature4
• Insolation, aka solar flux
• 𝐼!" = 1350 w/m2 = 1350 J/m2s
• 𝜀 = 1 means 100% energy in goes out
• 𝜀 < 1 means more energy out than in
• 𝜎 = 5.57 ∗ 10#$ W/m2K
§ Energy flux into Earth from the sun
§ Small increase in energy = large increase in temperature
§ Again, use black body model
• Assume Earth is perfect emitter of energy
• All energy in must go out
• 𝜀 = 1 for black body model
o 𝐹!" = 𝐼!" ∗ 𝜋𝑟%&'() 7 ∗ (1 − 𝛼)
§ Flux of energy in = insulation incoming * area * (1-albedo)
Climate Notes
• Atmosphere
o Troposphere is bottom layer
§ Mostly concerned with climate
§ Holds majority of clouds
§ 75% of atmosphere’s mass
o Tropopause right above troposphere
o Stratosphere above
§ Typically, stratosphere is separate from troposphere
§ Sometimes, volcanos/thunderstorms/etc. can release material into
stratosphere
• Surface Heating of Earth
o Equator, sun strikes at perpendicular angle
§ High energy input
§ Energy from equator à poles
• High à low
o Poles, sun strikes at oblique angle
§ Low energy input
o Factors influencing surface heating
§ Angle of sunlight
§ Distance light travels through atmosphere
§ Albedo of surfaces
• Reflectance
• Climate exists only because Earth is spherical and has non-
uniform albedo (land vs. water)
• Black body has no albedo
o Tendency is to go towards equilibrium
§ Which would be destruction of gradient = death
§ Maintain high à low gradient by inputting energy
• Sun is the energy for Earth’s gradient
o Variation in Temperature by Latitude
§ Mean annual temperature increases at low elevation, mesic, continental
locations
• Mesic: moist climate
o Xeric is dry climate
§ Temperature is about the same for 0-20° latitude
• Closer to equator
• Hottest mean annual temperature
o Not elevated
o Mesic (moist)
o Continental
, • Clouds and rainfall keep temperature uniform across tropics
o Clouds have high albedo
o Without clouds, the temperature would be much hotter at
0° than 20°
o So deforestation in the tropics would exacerbate climate
change
§ No trees = no clouds = hotter
• Hadley cells and adiabatic heating
o ITCZ, intertropical convergence zone, is where sun heats
air
o Heat of vaporization released when water condenses
o Towards the edge of Hadley cells are hot, dry deserts
§ Aka subtropical deserts
§ Xeric climate
o Solar equator hits 23.5° above and below geographical
equator
§ Tropics of Cancer & Capricorn
• Cancer = north = summer
• Capricorn = south = winter
o Trade winds
§ Whatever the name is, is where the wind comes
from
§ Ex: southeast trade winds come from the southeast
and go northwest
• Ocean Currents
o Linked to atmospheric circulation
o Winds push surface water
§ Fetch: when wind is blowing water in a sustained direction
§ Wind creates currents
o Land acts as deflection of currents
§ So due to continental drift, currents can change
o Water keeps surrounding land at moderate climate
o Ocean currents redistribute heat
§ British Isles are warmer than other areas of the same latitude
§ For deserts (Atacama and Namib), cold Antarctic currents veer away from
the land
• Intensifies the dry effect
• Fog, not rain, is main water source
• Fog is from cold water running against warm land mass
o These currents also relate to distribution of animals
§ Organisms on islands could be isolated species that followed currents
o Clouds form in a way that we cannot model well
§ Cloud type and distribution change reflectance
, § Cirrus clouds allow sunlight in but traps infrared radiation coming out
• Can heat planet
• Stratospheric clouds
§ Increase in clouds = increase in rainfall
§ Lower albedo of Earth = intensified heating
• From heat trapped
• Also from sea level rise
• Equations
o Constants
§ 𝑤 = 2897µm*K
• Wein’s constant
§ 𝐼!" = 1350 w/m2
• Incoming solar insolation
§ 𝜎 = 5.57 ∗ 10#$ W/m2K
• Stefan-Boltzman constant
§ 𝛼%&'() = 0.3
• Albedo
+
o Wien’s Displacement Law: λ* = ,
§ Max wavelength = wien’s constant / temperature (Kelvin)
§ 𝑤 = 2897µm*K
§ Black body temperature is the model
• Perfectly emitting black body with no atmosphere
• This is what T is in Wien’s Displacement Law
§ λ*,./0 = 0.5µm at 5800K
• Larger = shorter wavelength
§ λ*,12345 = 11.4µm at 255K
• Temperature at top of the Earth’s atmosphere
o Stefan-Boltzman Law: 𝐼!" = 𝜀𝜎𝑇 6
§ Incoming solar insolation = emissivity * Stefan-Boltzman constant *
temperature4
• Insolation, aka solar flux
• 𝐼!" = 1350 w/m2 = 1350 J/m2s
• 𝜀 = 1 means 100% energy in goes out
• 𝜀 < 1 means more energy out than in
• 𝜎 = 5.57 ∗ 10#$ W/m2K
§ Energy flux into Earth from the sun
§ Small increase in energy = large increase in temperature
§ Again, use black body model
• Assume Earth is perfect emitter of energy
• All energy in must go out
• 𝜀 = 1 for black body model
o 𝐹!" = 𝐼!" ∗ 𝜋𝑟%&'() 7 ∗ (1 − 𝛼)
§ Flux of energy in = insulation incoming * area * (1-albedo)
