Chapter 9 Insolation and Climate Study Set
What is the MOST important factor affecting climate?
1. Latitude
Name the 6 major factors affecting climate.
1. Latitude; 2. Elevation; 3.Prevailing (Planetary) winds; 4. Nearness to large bodies of water 5. Ocean currents; 6. Nearby mountain ranges
Weather a climate is arid or humid depends up these two factors:
1. Precipitation 2. Potential evapotranspiration
Why does the equator heat up more than the poles since they both get equal hours of daylight?
1. The sun's angle of insolation is lower at the poles; 2. More light is reflected at the poles because snow and ice is white; 3. The sunlight travels at an angle and so through more distance of atmosphere, so less energy reaches the surface.
Name some reasons that water heats up more slowly than land with equal energy.
1. Water reflects more; 2. Water is transparent; 3. Water layers mix; 3. More of the heat added to water results in vaporization rather than changing the temperature.
The strength of the insolation depends upon these three factors.
1. angle of insolation; 2. Duration of insolation; 3. The properties of the surface it strikes.
Why are temperatures lower at higher latitudes?
1. the angle of insolation is lower. 2. The duration of insolation varies over the year.
How much daylight do locations north of the Arctic circle receive on June 21? December 21?
24 hours on June 21 and 0 hours on December 21.
What angle of insolation is considered to be direct?
90 degrees
What is the highest value possible for angle of insolation?
90 degrees.
What is specific heat?
A measure of a substances resistance to temperature change.
What is angle of insolation?
A measure of how high the sun is up from the horizon.
How are humans increasing the amount of greenhouse gases in the atmosphere?
Activities such as: burning fossil fuels, cutting down trees, releasing methane (raising animals and harvesting petroleum)
When is the highest angle of insolation and rays most intense for a particular location on a particular day?
At noon because the sun is highest in the sky at this time.
Why does an insolation/temperature lag occur?
Because more energy continues to be received from the sun than is released to space until after the highest insolation. Also more energy continues to be released to space than is received from the sun until after the sun is above the horizon.
How is daylight distributed at the North and South Poles?
Both the North and South Poles receive 6 months of daylight followed by 6 months of darkness.
How is the earth's atmosphere primarily heated?
By changing the sun's light to heat and reradiating this heat to warm the atmosphere.
What within earth's atmosphere absorbs longer wavelengths such as infrared radiation?
Carbon dioxide, water vapor, and other "greenhouse" gases.
How are visible wavelengths (light) blocked from the sun?
Clouds reflect light back to space.
In water what process transfers energy deeper, away from the surface?
Convection
How does moisture vary with latitude?
Due to the air pressure belts and prevailing winds there are dry and wet belts at various latitudes. SEE ESRT p14.
What is duration of insolation?
Duration of insolation means daylight length, the length of time between sunrise and sunset.
What keeps much of the sun's radiation from reaching the earth?
Earth's atmosphere blocks much of the sun's radiation.
What are "greenhouse gases"?
Gases that absorb rather transmit heat.
Why is some "greenhouse effect" a good thing.
If the earth's atmopshere didn't trap some heat the earth would be too cold for life as we know it.
How do mountains effect climate?
If the windward side of a mountain receives moisture laden air then the air will rise, cool adiabatically releasing its moisture on the windward side. On the leeward side of the mountain the now dry air descends and warms adiabatically. This results in a cooler, wetter climate on the windward side and a warmer, drier climate (rain shadow desert) on the leeward side.
Seasonally how do temperatures lag behind insolation?
In the northern hemisphere, the greatest angles of insolation are received on June 21, but the hottest average temperature is not reached until late July or early August. In winter minimal insolation occurs on December 21, but the lowest average temperatures don't occur until late January or early February.
Name two areas of the world that are subject to monsoons?
India and southwest USA - Arizona
What three different things can happen to radiation that reaches earth?
It can be 1. reflected; 2. refracted; 3. absorbed
What is potential evapotranspiration dependent upon?
It is largely dependent upon temperature.
Why doesn't the Earth give off mostly light to space?
It is not hot enough to glow.
Water has a higher specific heat than land. What does this statement mean?
It takes more energy to change the temperature of water than it does land.
What is La Nina relative to El Nino?
La Nina is the opposite effect of El Nino
What two variables deteremine duration of insolation?
Latitude (distance from the equator) and season/date of the year.
What type of radiation does Earth primarily give off to space?
Longer wavelength infrared radiation(heat).
What angles of incidence (hitting the earth) reflect the most light?
Low angles of insolation.
What happens to the light that reaches the earth's surface.
Mostly it is changed into longer wavelength infrared radiation (heat) that in turn warms the atmosphere.
Is there always enough water available to evapotranspirate to full potential?
No, in arid regions there is not.
Can land transfer heat by convection?
No, it is not a fluid.
Does anyplace in the continental US receive direct rays of the sun at any time?
No. All of the continental US lies north of the Tropic of Cancer, 23 1/2 degrees north.
Is classification of a climate as arid or humid dependent solely upon preciptiation?
No. It is dependent upon P minus PE
On what day does the continental US receive its lowest angle of insolation?
On December 21, the winter solstice.
On what day does the continental US receive its most direct radiation for the year?
On June 21, the summer solstice.
Where do the direct rays of the sun fall on the summer solstice, June 21?
On the Tropic of Cancer, 23 1/2 degrees north latitude.
Where do the direct rays of the sun fall on the winter solstice, December 21?
On the Tropic of Cancer, 23 1/2 degrees south latitude.
What earth locations receive direct rays from the sun?
Only those locations in the tropics, that is between 23 1/2 degrees north latitude and 231/2 degrees south latitude.
How does latitude affect temperature.
Places further from the equator have lower temperatures and greater seasonal variation in climate.
Which absorbs more energy - rough surfaces or smooth surfaces?
Rough surfaces
What are monsoons?
Seasonally variations in the winds that result from the uneven heating of land and water.
Which reflects more energy - rough surfaces or smooth surfaces?
Smooth surfaces
What two variable define climate?
Temperature and moisture.
What is potential evapotranspiration?
The amount of water that COULD evaporate if water was available at all times.
What does whether a climate is arid or humid depend upon?
The difference between how much moisture an area gets (P) compared to how much moisture the area potentially needs (PE or Ep).
What is daylight length at the equator?
The equator receives 12 hours of daylight and 12 hours of darkness throughout the year, regardless of season.
Why do average temperatures decrease with increased latitude?
The further a location is from the equator, the lower its average angle of insolation.
How is angle of insolation related to the strength of insolation?
The greater the angle of insolation, the stronger the insolation.
What is the relationship between distance from the equator and seasonal variation in duration of insolation ?
The greater the latitude (distance from the equator), the greater the variation of daylight length seasonally.
Over the course of a day how do temperatures lag behind insolation?
The greatest amount of insolation is received at noon, but on average, highest temperatures occur at 2-3 PM. The least amount of insolation occurs at night, but the lowest temperatures occur shortly after dawn.
What gases in the atmosphere absorb and trap infrared radiation (heat) and prevent this heat from escaping to space?
The green house gases - carbon dioxide, water vapor, and methane to name those you MUST know.
Describe the weather on the leeward side of a mountain relative to the windward side.
The leeward side is warmer and drier.
What is climate?
The long term temperature and moisture conditions of an area.
Why are direct rays more intense than rays with a lower angle of insolation?
The lower the angle of insolation the more spread out the rays are over earth's surface.
What layer of the atmosphere absorbs and protects the earth from short wavelength radiation such as ultraviolet, x-rays and gamma rays?
The ozone layer.
Why is global climate change taking place?
The quantity of "greenhouse gases" in the atmosphere is increasing.
What is the windward side of a mountain?
The side that faces the wind -- the side that the wind hits first.
What is meant by the insolation and temperature time lag?
The time of greatest/least temperature comes after the greatest/least amount of insolation.
Describe the weather on the windward side of a mountain relative to the leeward side?
The windward side is cooler and wetter.
How does the nearness of large bodies of water affect climate?
They "moderate" climate -- that is they make the climate more medium. Hots are not as hot and colds are not as cold.
What type of radiation does earth receive the most of from the sun?
Visible wavelengths - light.
How do ocean currents affect climate?
Warm ocean currents warm the air above them and cold currents cool the air. As a result they bring warmer or cooler air to nearby land areas.
What is a time lag?
When something comes after something else.
When is there dynamic equilibrium between incoming energy from the sun and outgoing energy to space?
When temperatures reach their highest point, before they begin to drop and also when they reach their lowest point, before they began to rise.
If P is less than Ep a climate is ___________.
arid
Climates are classified as ________ or ________ based on moisture.
arid or humid
How does land transfer energy?
by conduction -- it is a solid.
What are the greenhouse gases?
carbon dioxide, water vapor, and methane..... amongst others.
Which absorbs more light - dark colored objects or light colored objects?
dark colored objects
Which heats and cools more quickly - dark colored objects or light colored objects?
dark colored objects
An increase in ________________ mimics an increase in latitude.
elevation
If P is greater than Ep a climate is _____________.
humid
What does insolation mean and what three words is it a contraction of?
incoming solar radiation
Which heats more quickly - land or water?
land
The "greenhouse effect" takes place because the earth's atmosphere lets _______________ through (is transparent to) but traps (absorbs) some ______________ radiation.
light (visible wavelengths) ..... heat (infrared)
Which reflects more light - dark colored objects or light colored objects?
light colored objects
Higher elevations experience _________ temperatures.
lower
Winds that blow in from the sea are high in _________________.
moisture
A good absorber is a good __________________.
radiator
The prevailing winds influence both _____________ and _________ content of the air.
temperature .....moisture
What is El Nino?
the abnormal warming of surface ocean waters in the eastern tropical Pacific is what's called the El Nino/Southern Oscillation or ENSO
Winds that blow from the tropics would be ___________.
warm
Which reflects more energy - land or water
water
Do all areas of the earth - both poles and the equator have equal hours of daylight over the course of a year?
yes
