Quiz 4 Flashcards
Why does Earth have seasons?
The axis is tilted
When is Earth closest to the Sun in its present orbit? How does this “close pass” position affect the amount of radiation received on Earth?
earth is (closest) to sun on (perihelion) on January 3.
This is more radiation. The distance of 147 million kilometer from the earth.
as it moves fastest during perigee the solar day would be largest. Whereas the solar day the solar day wold be smallest during apogee( aphelion = is away on July, 4 ) because the earth moves much slower at this position.
when earth is in aphelion it receives less radiation from sun and temperature would be the lowest.
Earth’s tilt is slowly decreasing today. As it does so, are the Polar Regions receiving more or less solar radiation in summer? In winter?
earth tilt decreases, the poles would be away from sun during (summer). less radiation in the summer.
during the (winter), the poles will be directly towards the sun. they would receive more solar radiation.
How is axial precession different from precession of the ellipse?
Axial precession is the wobbling motion of the earth caused by the gravitational pull of sun and moon causing slight bulge in the diameter of the earth at the equator. 23.5
precession of the eclipse( precession is slower) is the entire elliptical shape of earth orbit tends to rotate. It is slower in space.
*the combined motions of these precessions leads to the occurrence of equinoxes( twice a year, march, & September same length day&night). and solstices (revolution around sun .
How does eccentricity combine with precession to control a key aspect of the amount of insolation Earth receives?
both combine would result variations of distance between earth and the sun by the seasons with the cycle of 23,000 years. solar radiation is more on perihelion and less on aphelion.
the high eccentricity would result in large contrast in the distance between the earth and sun low eccentricity would result in low contrasts.
