Transcript Earth as a System

Earth as a System
NASA Satellite Images for 2007
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Step 1: Single Image Analysis
Individually examine one of the images at your table and answer the
following questions:
1)
What variable did you examine and what is the range of values
shown on the scale bars?
2)
Where in the world do you find the extreme values of the data on
your images? What are the extremes? Why do these locations
experience the extremes and not other locations?
3)
Are any patterns in the data noticeable? Are patterns different on
different continents? Different over water than over land? Explain
these patterns.
Step 2: Whole Year
As a group, compare all the images at your table and answer the following questions:
1.
What changes do you see through the year? What explanations can you suggest for
these patterns?
2.
Choose a location or region. During which months do the extreme highs and lows
occur? What explanations can you suggest for the timing of those extremes?
3.
Which regions experience both the extreme highs and lows? Which regions don’t
experience the extremes? Why do you think this happens?
4.
What differences, if any, do you find between the year’s variations over the oceans
versus the year’s variations over the continents?
5.
Are there regions that remain relatively unchanged over the year? Why do you think
this happens?
Step 3: Comparing 2 Variables
1.
Get together in the following pairs:
Group One (Insolation) with Group Two (Surface Temperature)
Group Three (Cloud Fraction) with Group Four (Precipitation)
Group Five (Aerosols) with Group Six (Biosphere)
2.
Arrange your images in chronological order so that they are next to each other.
3.
Identify the relationships and associations between the variables. Use the
following guiding questions:
a)
b)
4.
What relationship do you see between insolation and surface temperature? Cloud
fraction and precipitation? Aerosols and Biosphere?
Do the relationships appear to be directly or inversely proportional? Explain.
Record the relationships you have identified between the two variables. Also
explain the methods you used to identify these relationships.
Step 4: All Variables in 1 Season
Get into your original groups where you will examine all the variables for one
season. Answer the following questions:
1.
Which regions experience the extreme highs and lows for each variable?
2.
Which regions don’t experience the extremes? Why do you think this
occurs?
3.
What differences, if any, do you find between variations of variables over the
oceans versus variations in variables over the continents?
4.
What amounts of insolation, surface temperature, cloud fraction,
precipitation and aerosols characterize the world’s most vegetated regions
for a particular month?
5.
Where is the greatest concentration of aerosols originating from and how
would you characterize that particular environment based on the six
images?
Step 5: Comparing Opposite Seasons
Pair up with the group of the opposite season:
January
July
March
September
May
November
1. Which variables change the most over the six-month
period? Which variables change the least? Why do
you think this happens?
2. Do you see any relationships among the variables that
you didn’t see previously?
Clouds and Precipitation
1.
What is the cloud fraction over equatorial Africa?
2.
Notice that cloud fraction values over the equatorial region of Africa are quite
high throughout the year (>50%). Also, notice that precipitation is high as are
NDVI values.
What type of environment might this be?
If cloud fraction values were decreased to less than 25%, what environmental
changes would you expect for this region [refer to global biome maps]?
3.
Would you expect high precipitation values (e.g. >200 mm) to exist under low cloud
fraction? What additional information might be useful in making these statements?
[think about the role of geography in precipitation, as in rain shadow]
4.
What about a similar reduction in the Amazon region of South America? What
effects would these changes have on the vegetation (NDVI)? Why would you expect
these changes?
[Connect ideas to form expectations or hypotheses! The point is not to know what
changes will occur but rather to use what you know to make predictions!]
1.
2.
Biosphere
1. How are the patterns in the ocean (Chlorophyll Concentration)
similar to the patterns on land (Vegetation)?
2. What time of year does it seem like the Earth is the “greenest”?
3. How do the other five variables influence changes in biomass?
Explain.
Vacation Location…
1. Choose a location where your group would like to go on
vacation (any place on Earth is possible)!
2. What is the best month to visit that location? Why
3. What activities would they be engaged in? What types of
clothing would they need to pack?
4. If you were only able to go on vacation during the month of
May, where would be the best location for your trip? Answer
the same question for the other five months available.
Aerosols
1.
Find an area on the aerosols images that is black during all months.
Why would these areas be black in all images? What is constant
during all months for these regions?
2.
What surface cover commonalities exist between Greenland and
other Northern latitudes during January, March and December?
3.
Examine biosphere images. What do you think the black areas in the
images could be? [Look at the aerosols]
4.
Notice that some, but not all, aerosols show up as black areas in the
biosphere images. Why might this occur? Make a list of natural and
anthropogenic sources of aerosols. Are all aerosols are the same?