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Our Corner of the Universe. 100 mil ly. 5 mil ly. Our Neighborhood. Earth’s rotation, orbit and the seasons. Only 50% of the Earth’s surface can be “lit” by the sun Because the Earth’s axis is tilted the area covered by this 50% varies throughout the year. Most important variables. - PowerPoint PPT Presentation
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Our Corner of the UniverseOur Corner of the Universe
100 mil ly 5 mil ly
Our NeighborhoodOur Neighborhood
Earth’s rotation, orbit and the Earth’s rotation, orbit and the seasonsseasons
Only 50% of the Only 50% of the Earth’s surface can Earth’s surface can be “lit” by the sunbe “lit” by the sun
Because the Earth’s Because the Earth’s axis is tilted the area axis is tilted the area covered by this 50% covered by this 50% varies throughout the varies throughout the yearyear
Most important variablesMost important variables
Earth’s orbit is 365.25 days longEarth’s orbit is 365.25 days long
Earth’s axis of rotation tilts 23.5° from the Earth’s axis of rotation tilts 23.5° from the perpendicularperpendicular
These two variables account for the seasonal These two variables account for the seasonal changes in weather patterns that we observe changes in weather patterns that we observe in a given yearin a given year
We have four seasons: why?We have four seasons: why?
The Earth’s axis of The Earth’s axis of rotation is tilted at rotation is tilted at
23.5° from the 23.5° from the perpendicularperpendicular
Earth-Sun RelationsEarth-Sun Relations
LatitudeLatitude
Affects the amount of insolation received Affects the amount of insolation received at the Earth’s surfaceat the Earth’s surface
The The subsolar pointsubsolar point (at right angles to the (at right angles to the plane of the ecliptic) receives most plane of the ecliptic) receives most insolationinsolation Insolation decreases north and south of this Insolation decreases north and south of this
pointpoint The subsolar point migrates from 23.5°N The subsolar point migrates from 23.5°N
in the summer to 23.5°S in the winterin the summer to 23.5°S in the winter
Subsolar point
The latitudinal zonesThe latitudinal zones
Perihelion vs AphelionPerihelion vs Aphelion
MILANKOVITCH CYCLESMILANKOVITCH CYCLES
- ACCOUNTS ACCOUNTS FOR FOR PERIODIC PERIODIC GLACIATION GLACIATION OF EARTHOF EARTH
MILANKOVITCH CYCLESMILANKOVITCH CYCLES
MILANKOVITCH CYCLESMILANKOVITCH CYCLES
THE NEXT ICE AGE?
WHEN
