Name _______________________________Period ______
Weather and climate are the two major abiotic (nonliving) factors responsible for determining the major geographic ecosystems called biomes.
Search the web and give a definition of weather:
The state of the atmosphere with respect to wind, temperature, cloudiness, moisture, pressure, etc.
Search the web and give a definition of climate:
the composite or generally prevailing weather conditions of a region, as temperature, air pressure, humidity, precipitation, sunshine, cloudiness, and winds, throughout the year, averaged over a series of years.
Climate is closely associated with the seasons, but do you know what causes the seasons? Log on to the website below.
After watching the video, describe what causes the earth’s seasons. Give examples of the earth’s position to the sun in December vs. June and compare the northern and southern hemispheres. As the earth spins on its axis, producing night and day, it also moves about the sun in an elliptical (elongated circle) orbit that requires about 365 1/4 days to complete. The earth's spin axis is tilted with respect to its orbital plane. This is what causes the seasons. When the earth's axis points towards the sun, it is summer for that hemisphere. When the earth's axis points away, winter can be expected. Since the tilt of the axis is 23 1/2 degrees, the North Pole never points directly at the Sun, but on the summer solstice it points as close as it can, and on the winter solstice as far as it can. Midway between these two times, in spring and autumn, the spin axis of the earth points 90 degrees away from the sun. This means that on this date, day and night have about the same length: 12 hours each, more or less.
What do the red lines along the edge represent? What do the blue lines along the edge represent? The red represents warm convection currents and the blue represents cold convection currents. [pic]
The diagram above shows a convection current if the earth is not spinning. Note that if the earth is not spinning, cold air from the poles would flow straight down to the equator where it would be warmed and would rise straight back up to the poles. However, the earth IS spinning, so we need to investigate what the rotation of the earth does to the winds.
For starters, which way does the earth spin? Do you know? Click on the link below to find out. http://mmert.org/goltz/Universe/size5earth.gif
The Earth rotates to the east.
What is the Coriolis Effect? For general information, log on to the website below. Read the background information, watch the short video of the merry-go-round at the bottom and then answer the questions below. Coriolis Part 1 http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/crls.rxml
What is the Coriolis Effect?
Once air has been set in motion by the pressure gradient force, it undergoes an apparent deflection from its path, as seen by an observer on the earth. This apparent deflection is called the "Coriolis force" and is a result of the earth's rotation. Which way does the Coriolis Effect bend the winds in the Northern Hemisphere? Right
Which way does the Coriolis Effect bend the winds in the Southern Hemisphere? Left
What factors determine how much the winds bend?
The amount of deflection the air makes is directly related to both the speed at which the air is moving and its latitude.
Click on the link below and watch the winds bend. Coriolis Part 2 http://www.classzone.com/books/earth_science/terc/content/visualizations/es1905/es1905page01.cfm?chapter_no=visualization
Which hemisphere is shown and which way are the winds bending?
Northern Hemisphere, right.
Some people say that water goes down the toilet counterclockwise in the Northern Hemisphere, clockwise in the Southern Hemisphere, and straight down at the equator, due to the Coriolis Effect. Click on the...