Lecture 4 Radiation, Earth-Sun Relations Flashcards
At ______, which is Earth’s closest position to the Sun, occurring on January 3 during the Northern Hemisphere winter
perihelion
1.47×10^8
km
At ______, which is Earth’s farthest position from the Sun, occurring on July 4 during the Northern Hemisphere summer
Aphelion
1.52×10^8
km
The ______ is the periodic variation in the Sun’s activity and appearance over time.
Solar cycle
______ are surface disturbances caused by magnetic storms.
Sunspots
Clouds of electrically charged particles emitted by the Sun’s corona and surging towards the
Earth are called?
Solar wind
The ______ deflects the solar wind toward both of Earth’s poles so that only a small portion of it enters the upper atmosphere.
magnetosphere
______ that are aimed toward Earth often cause spectacular auroras
Coronal mass ejections
True or False: Short wavelengths have high frequency.
True, long, have low frequency
The Sun emits radiant energy composed of ______% ultraviolet, X-ray, and gamma-ray wavelengths; ______% visible light wavelengths; and ______% infrared wavelengths
8, 47, 45
True or False: the hotter the object, the shorter the mean wavelength of maximum intensity emitted
True
True or False: The sun inputs short radiation and the earth outputs long radiation.
True
______ is the region at the top of the atmosphere
Thermopause
______ is radiation arriving at Earth’s atmosphere and surface
Insolation
The Sun has a ‘surface’ temperature of approximately
_____K, while the Earth has a temperature of approximately ______ K
6000, 300
______ is the only point receiving perpendicular insolation at a given moment—that is, the Sun is directly overhead.
Subsolar point
Why is the equator the hottest?
Sun’s rays arrive parallel to each other at Earth’s surface
A ______ is a perfect absorber of radiant energy; it absorbs and subsequently emits all the radiant energy that it receives
blackbody, ie sun
What is the equation for net radiation?
Q* = Incoming - Outgoing
Q* = (K9 + L 9) - (K8 + L8)
K down (K down): Incoming Shortwave K up(K up): Outgoing Shortwave L up(L up): Outgoing Longwave L down (L down): Incoming Longwave
True or False: Kdown values are greatest in the equatorial regions and lowest in the polar regions with
much more variation in the polar regions.
True
What are the 5 reasons for the seasons?
Revolution
Orbit around the Sun; requires 365.24 days to complete at 107 280 km·h−1
Rotation
Earth turning on its axis; takes approximately 24 hours to complete
Tilt
Alignment of axis at about 23.5° angle from perpendicular to the plane of the ecliptic (the plane of Earth’s orbit)
Axial parallelism
Unchanging (fixed) axial alignment, with Polaris directly overhead at the North Pole throughout the year
Sphericity
Oblate spheroidal shape lit by Sun’s parallel rays; the geoid
______determines daylength creates the apparent deflection of winds and ocean currents and produces the twice-daily rise and fall of the ocean tides in relation to the gravitational pull of the Sun and the Moon.
Rotation
True or False: The speed of rotation is fastest at the poles.
False, slowest at poles, fastest at equator
The dividing line between day and night is the ______
Circle of illumination
Earth’s axis is tilted about ______.
23.5 degrees
______ is a plane (flat surface) intersecting all the points of Earth’s orbit.
plane of ecliptic
______ is Earth’s axis remains aligned the same throughout the year
Axial parallelism
True or False: net radiation is most negative in the equatorial regions
False, polar regions
The times around December 21 and June 21 are solstices. Strictly speaking, the solstices are specific points in time at which the Sun’s declination is at its position farthest north at the ______, or south at the ________
Tropic of cancer, Tropic of capricorn
During the ______, the circle of illumination excludes the North Pole region from sunlight but includes the South Pole region. The subsolar point is about 23.5° S latitude, the Tropic of Capricorn parallel.
December solstice
______ is when the Earth experiences 12- hour day and q2 hour night.
equinox
______ is a measure of the ability or capacity of a system to do work
energy
True or False: Energy cannot be created or destroyed, but the form of energy can change. Energy can be transferred from one location to another
True
Heat absorbed or released as the result of a phase change is called ______.
Latent
______ is the energy a object posses due to motion
kinetic
______ is energy within object or system due to movement of particles within object or system
Thermal
______ energy stored in object due to its position relative
Potential
