Radiation and Energy Balance, Pt.1 Flashcards
When was our solar system formed?
~4.6 billion years ago
Our sun captured ___% of the matter from a nebula of dust and gas. The remaining ___% went to forming the remaining planets, moons, and all other objects found in our solar system.
99.9, 0.1
True or False: The sun is the only object in our solar system, massive enough to sustain nuclear fusion in its core, producing radiant energy.
True
Describe Solar Radiation:
Solar radiation occupies a portion of the electromagnetic spectrum of radiant energy.
Describe Radiant Energy:
Radiant energy travels at the speed of light to Earth. (~300,000 km/s). Light reaches Earth from the Sun in about 8 minutes and 20 seconds. The total spectrum of this radiant energy is made up of different wavelengths.
What two ways can you describe Electromagnetic Radiation (EMR)?
Wavelength and Frequency
Define a wavelength:
distance between adjacent wave crests (ex. Meters is too large to measure, that’s why we use nanometers.)
Short wavelengths have _____ frequency. Long wavelengths have ____ frequency.
high and low
Define Frequency:
time between passes of adjacent waves, how many waves can pass a given area in time.
What are the units for frequency?
(cycles per second, Hertz, Hz)
What is a nanometer?
A nanometer (symbol nm) is a unit of length in the metric system, equal to one billionth of a meter. It can be written in scientific notation as 1×10−9 m which is 1 / 1,000,000,000 meter. The nine signifies how many zeros we have.
What is a micrometer?
A micrometer (symbol μm) is metric system unit of length equal to one millionth of a meter, or equivalently, one thousandth of a millimeter. It is also commonly known as a micron. It can be written as 1×10−6 m, meaning 1 / 1,000,000 meter.
Can ‘micron’ be interchanged with micrometer?
Yes
Wavelength of radiated energy depends on _________ of the radiating body.
temperature
What kind of wave energy does the sun radiate?
The sun is hot, it radiates shorter wave energy, mainly visible and near infrared portion of the spectrum.
What kind of wavelength does the earth radiate?
The earth is cooler, so it radiates longer wave energy, mainly thermal infrared.
What does UTC mean?
Greenwich Mean Time
How do you convert UTC to Winnipeg?
Winnipeg = UTC –6
The Band 13 sensor on the satellite detects ________ radiation that is good at showing where clouds are day and night.
thermal infrared
What is Solar Energy?
Energy is the capacity of a physical system to do work.
What is the unit measurement for work?
1 Joule
How is Solar Energy generated?
By the nuclear fusion reaction process in which pairs of hydrogen nuclei are joined, to form helium, and emit a large amount of energy. Essentially mass is converted to energy. Pairs of hydrogen molecules join, then mass is lost and then converted into energy, then radiated to earth.
What is the Solar Constant? *
Solar Constant = Average intensity of sunlight 1372 watts per square meter (W/m2)
1 Watt = 1 ____
Joule (J) of energy/second
1 J = _________
0.239 calories and/or 1 Watt
True or False: the solar constant is a short term average.
false, its a long term average.
Define Sunspots:
Sunspots are caused by magnetic storms on the Sun. They can be more than 12 times Earth’s diameter. Their temperatures are less than the temperatures of their surroundings, which is why we see them as darker spots in images.
Sunspots have an activity cycle of ____ years.
11
Is it true that sunspots fluctuate over the years? Decreasing and increasing in amounts.
Yes.
True or False: The sun rotates, about once every 27 days (like the earth, faster at the equator than the poles). Increasing sunspots are from increasing solar intensity.
True.
How often does the Sun rotate?
Once every 27 days.
When/How did the measurement of sun spots begin?
That numbering began on January 5th, 1972, and on June 14, 2002, reached the active region number of 10,000. But since June 14th, active region reports drop at least the leading digit.
-0001, 0002. Instead of 10,001 and 10,002
What is Solar Wind?
Solar wind is clouds of electrically charged particles, principally hydrogen nuclei and free electrons.
What are solar winds composed of?
principally hydrogen nuclei and free electrons
True or False: Solar wind first interacts with earths magnetosphere, which deflects the solar wind toward both of Earth’s poles.
True.
Do solar winds go into the ionosphere?
Yes, a small portion of it enters the atmosphere and interacting with our ionosphere, producing auroras. (At 80 – 500kms above the surface).
