Quaternary EnvironmentsQuaternary EnvironmentsClimate and Climatic VariationClimate and Climatic Variation
Geologic Time ScaleGeologic Time Scale
Glacial Time Glacial Time Scales in the Scales in the Northern Northern HemisphereHemisphere
Blytt-Sernander Scheme of European Blytt-Sernander Scheme of European Peat StratigraphyPeat Stratigraphy
Scale of VariationScale of Variation
The Climate SystemThe Climate System
End-product ofEnd-product of AtmosphereAtmosphere OceansOceans BiosphereBiosphere Land surfaceLand surface CryosphereCryosphere
Major Components of the Climate Major Components of the Climate SystemSystem
AtmosphereAtmosphere
CloudsClouds Atmospheric circulationAtmospheric circulation Greenhouse gasses (Water, Carbon Greenhouse gasses (Water, Carbon
Dioxide, Methane, Nitrous Oxides)Dioxide, Methane, Nitrous Oxides) TemperatureTemperature Incoming solar radiation (INSOLATION)Incoming solar radiation (INSOLATION)
Insolation (W/mInsolation (W/m22))
OceansOceans
Thermohaline CirculationThermohaline Circulation Thermal InertiaThermal Inertia Source of MoistureSource of Moisture Sea Level RiseSea Level Rise
Melting of ice sheetsMelting of ice sheets Thermal expansionThermal expansion
Thermohaline CirculationThermohaline Circulation
(Schmitz 1995)
Cross Section of Thermohaline Cross Section of Thermohaline CirculationCirculation
(Brown et al. 1989)
BiosphereBiosphere
Vegetation Effects on ClimateVegetation Effects on Climate AlbedoAlbedo RoughnessRoughness EvapotranspirationEvapotranspiration Atmospheric compositionAtmospheric composition
Vegetation Response to ClimateVegetation Response to Climate Faunal Response to ClimateFaunal Response to Climate
COCO22 Sequestration Sequestration
Land SurfaceLand Surface
Effects of Land Surface on the Climate Effects of Land Surface on the Climate SystemSystem AspectAspect ElevationElevation AlbedoAlbedo
Response to the Climate SystemResponse to the Climate System River systemsRiver systems Sea level changeSea level change Glacial evidenceGlacial evidence
CryosphereCryosphere
Ice ExtentIce Extent AlbedoAlbedo
Feedback EffectsFeedback Effects Temperature ControlTemperature Control
Energy Balance in the AtmosphereEnergy Balance in the Atmosphere
Sensitive heat flux (H)Sensitive heat flux (H) Latent heat flux (LE)Latent heat flux (LE) Bowen Ratio (H/LE)Bowen Ratio (H/LE)
Energy BalanceEnergy Balance
Time Scales of Climatic VariationTime Scales of Climatic Variation
Climate Varies on All Time ScalesClimate Varies on All Time Scales Driving ProcessesDriving Processes
Climate Variation Over Multiple Climate Variation Over Multiple ScalesScales
Variations of the Earth’s Orbital Variations of the Earth’s Orbital ParametersParameters
James Croll; Scottish natural historian James Croll; Scottish natural historian 18671867
Milankovitch; Elaborated on Croll’s original Milankovitch; Elaborated on Croll’s original hypothesis in 1941hypothesis in 1941
Berger; Advances Milankovitch’s work in Berger; Advances Milankovitch’s work in the late 1970sthe late 1970s
Milankovitch CyclesMilankovitch Cycles
EccentricityEccentricity – 95,800 year period. Changes in – 95,800 year period. Changes in the orbital path of the Earth around the Sun. the orbital path of the Earth around the Sun. Affects the relative intensities of the seasons.Affects the relative intensities of the seasons.
ObliquityObliquity – 41,000 year period. Changes in – 41,000 year period. Changes in axial tilt of the Earth.axial tilt of the Earth.
PrecessionPrecession – 21,700 year period. Wobble of – 21,700 year period. Wobble of the axis causing a precession of the equinoxes. the axis causing a precession of the equinoxes. Perihelion during Northern Hemisphere summer Perihelion during Northern Hemisphere summer occurred 11,000 years ago.occurred 11,000 years ago.
Orbital FactorsOrbital Factors
Wobble on the Earth’s AxisWobble on the Earth’s Axis
PrecessionPrecession
Insolation and Insolation and 1818OO
Long Term Solar RadiationLong Term Solar Radiation
http://www-istp.gsfc.nasa.gov/Education/Intro.html; Illustration by Steele Hill