Remote Sensing Test
Science Olympiad
Fairfax High School Invitational
Saturday January 7, 2017
School: ______
Team #: ______
Students: ______
______
Station 1 Questions
These two images are portions of Greenland's coastal regions. The above images show are two MODIS views of the west coast just north of the Arctic Circle that were collected on 25 February 2007 and 27 August 2007. The lower images are magnified images of the regions shown within the red rectangle. They both show the same region.
1) What is the grey band that extends north/south through the right half of the August image (the grey band runs right through the red box and down to the bottom of the image?
2) What are the pockmarks (shown in blue) that are seen in the August image?
3) Why are there no pockmarks in the February image?
4) Both images have the same white shape covering the right half of the image. What is this white shape?
Station 2 Questions
This image of the area around Ross Island, Antarctica was collected at 1:15 in the early morning on December 19, 2008 (New Zealand Daylight Time).
5) Why is there considerable breakage of ice flows from the mainland?
6) The image was taken at 1:15 AM New Zealand time, but was stamped December, 18, 2008, 12:15 UT. What is UT?
7) There are some shadows shown along the edges of the mountains. How can there be shadows at 1:15 in the morning?
8) In which direction is the sun from the mountains shown?
Station 3 Questions
This Aqua-MODIS image was taken several days after Hurricane Norbert passed through the Gulf of Mexico area in October 2008. The red line shows the path Nobert took.
9) Was Norbert’s heading in a southerly or northerly path?
10) How did you determine (from the image) your answer to the above question?
11) Why did Norbert’s path change from a westerly direction to an easterly direction?
12) Even if the red line had not been drawn, it would have been fairly easy to estimate Norbert’s actual path. Why?
Station 4 Questions
Consider the first picture to answer questions 13 and 14
These two SeaWiFS images were collected ten days apart.
The first was collected on September 18, 2002 -- before Tropical Storm/ Hurricane Isidore blew through. Part of the cloud field associated with Isidore is visible in the lower right corner of the left-hand frame.
The second image was collected on September 28, 2002 and shows a marked increase in the albedo of the coastal waters, particularly in the northern Gulf of Mexico.
The cloud pattern in the lower right corner of the right-hand image is part of Tropical Storm Lili. Lili -- reclassified as a hurricane on 30 September 2002 -- is currently forecast to follow a path similar to Isidore's a week before.
13) What is albedo?
14) What would cause the increase in albedo?
Consider the bottom picture to answer questions 15 - 18
This is an IKONOS image of the Bear glacier in the Denai Peninsula of Alaska.
15) Which direction is the glacier flowing in this image?
16) What hazard to man is represented in this image?
17) What is the name given to the small pieces of ice that break off of a glacier into water?
18) While this image is clear, many times clouds and ice appear white. How are scientists able to distinguish clearly between clouds and ice?
Station 5 Questions
This SeaWiFS image was collected on November 7, 2004. Even at the scale shown, a pool of dark water (right of image center) is visible off of the western coast of the northern part of the Florida peninsula.
19) What could cause this dark area?
20) What is the body of water in the very upper left-hand corner of the image?
21) What body of water shown in this image is completely covered by clouds?
22) What is a false color composite?
23) Which of the above images is a cyclone-type system found in the northern hemisphere?
24) Explain how you arrived at your answer to the above question.
Station 6 Questions
This MODIS image was collected in 2010
25) What is the name of water shown between Russia (on the left) and the U.S. (on the right)?
26) There are two very small islands shown almost in the middle of the image. What is famous about the area between them?
27) What is the direction of the current between these two land masses?
28) What this image taken during the summer or winter?
29) What feature of this image led you to your answer to the above question?
Station 7 Questions
30) What is meant by the term ‘cloud fraction’?
31) Based on these image does there seem to be a difference in the cloud fraction during the day and at night?
32) Explain how you arrived at your answer to the above question based on the images?
33) In general, are the levels of cloud cover greater over land masses or over the oceans?
34) Over what features are the cloud covers least?
35) What color is above the features?
Station 8 Questions
Seasonal variation in snow cover from year to year in a smaller region is illustrated by this pair of Landsat-1 images of the central Sierra Nevada highland
36) Make an estimate, using the above Landsat image pair, of the amount that the runoff water would increase from the melting of the 1975 snowpack in the Sierra Nevada compared with 1977. Assume the snow is melted entirely.
37) Explain how you arrived at your answer to the question above.
Station 9 Questions
There are no Images at this station. Simply answer questions 38-43.
38) Match the wavelengths AND comment shown here with the appropriate Regions on your answer sheet. Every letter will be used. Letters A – J will each be used only once and should be placed on the FIRST blank in front of the Region name. Letters K – R may be used more than once and should be placed on the SECOND blank in front of the Region name.
A - < .03 nm B - .03 to 30 nm C - .03 to .4 mm
D - .3 to .4 mm E - .4 to .7 mm F - .7 to 100 mm
G - .7 to 3 mm H – 3 to 14 mm I - .1 to 100 cm
J - > 100 cm
K – Available for remote sensing the Earth & can be imaged with photographic film
L – Available for remote sensing the Earth BUT CANNNOT be imaged with photographic film
M – Partially available for remote sensing as shorter wavelengths in the Region are absorbed by ozone in the Earth’s atmosphere
N – Partially available for remote sensing as shorter wavelengths in the Region can be imaged with photographic film
O – Partially available for remote sensing as the longer wavelengths in the Region pass through clouds, fog, and rain
P – Not available for remote sensing as the Region is entirely absorbed by the Earth’s atmosphere
R – Not normally used for Remote Sensing the Earth
39) Can oil spills be detected by LandSat imagery?
40) State the TWO main types of Remote Sensing. Then BRIEFLY explain what each type is.
41) Infrared photography is an example of which of the above two types of Remote Sensing?
42) RADAR is an example of which of the above two types of Remote Sensing?
43) Once data is collected, images MAY need to be corrected. They are typically corrected through two methods.
(A) Which method gives a scale to the pixel values?
(B) Which method rescales each frequency band to its minimum value?
Station 10 Questions
Consider the top picture for questions 44 - 46
Sea ice is easy to monitor from space as long as the scene is largely cloudfree when a satellite passes overhead. Polar orbiting satellites repeatedly pass near the poles on a daily cycle. Visible and radar imagery is effective in observing sea ice on a continual basis. Radar at bands that penetrate clouds (e.g., L-band) is now operational (Canada's Radarsat, for example) to monitor shipping lanes subject to ice hazards.
Below is a SIR-C multiband color composite that shows ice in the Weddell Sea, off Antarctica, south of the Atlantic Ocean. Open water polynyas show as darker tones.
44) Why does this ice show a blocky or patchwork pattern?
45) You will notice several elongated fissures in this ice? These indicate that it is most likely which of the following months?
(A) January (B) April (C) July (D) October
46) Often monitoring ice can be difficult due to cloud cover. To correct for the cloud cover which bands of radar are often used (that easily penetrate clouds)?
(A) L Bands (B) S Bands (C) C Bands (D) X Bands
Consider the bottom picture for questions 47 and 48
47) Often offshore current cause ice to form swirls as shown above. What are the swirls called?
48) Which way are these swirls spinning?
Station 11 Questions
Consider the top picture to answer 49 - 52
Meteorological satellites are particularly adept at recognizing snow - it appears bright white and usually continuous over large areas (clouds are either discontinuous or a dull gray). This is a typical Metsat view.
49) The above image shows a snowstorm that blanketed a portion of the central U.S. In which direction did this particular storm track?
50) Why is there a triangular green segment over the north-central plain states?
51) If this storm had passed through this past week, would we see the ground outside be snow covered?
52) Why is there a sharp line between the green and the white running from northern Texas up to Lake Erie?
Station 11 Questions Continued
Consider the bottom grid of four images to answer questions 53 - 55
These four MODIS images show the extent of snow cover in different years.
Over a longer period, satellite imagery can show potential flooding from spring thaws and image interpreters can estimate expected quantities of water runoff by monitoring snow cover over large regions. Satellite observations of surfaces blanketed by snow (in the U.S. principally in mountains and high prairies) suffice to measure the areal extent of the masses likely to melt.
53) During which of the years pictured is there least likely to be flooding and mudslides in central California?
54) During which of the years pictured is there least likely to be flooding along the Mississippi?
55) Unfortunately, snow-cover itself is insufficient data for correctly predicting spring floods. What additional information would make the predictions much more accurate?
Station 12 Questions
Only question 58 refers directly to the picture at this station
56) What is Blackbody Radiation?
57) What is meant by Earth’s “Radiation Budget”?
58) Considering the picture at this station, label the components of earth’s radiation identified in the picture. Be sure to indicate in your answer the role each of these components play in Earth’s Energy Budget
Considering the basic energy balance model equation:
Ts= Te+ dT
59) What do the three variables in the equation represent?
60) What is the currently accepted value of dT?
61) What is the difference between a Global energy balance model and a Zonal, or latitudinal, model? Which is considered to be more accurate and why?