Landsat MSS Imagery Interpretation

(revised 06/01)

Introduction and Purpose

The objectives of this laboratory assignment include gaining a basic understanding of MSS imagery, familiarity with the spectral characteristics of Landsat MSS imagery, and experience with image interpretation. In conjunction with the individual band and color composite imagery, you will use USGS topographic map sheets at a scale of 1:250,000 for purposes of comparison. Multispectral scanners from orbital altitudes offer repetitive synoptic views of the terrain. This regional scale database is most useful for inventorying and monitoring large elements quickly, with frequent repetition and a low cost per unit area.

Maps and Imagery

1) Albany, NY Landsat MSS Images: 17 September, 1973—Bands 4,5,7 and color composite

2) New York City-New Jersey Images: 25 January, 1973—Bands 4,5, 6 and composite

3) USGS 1:250,000 topographic maps:

A) Albany-Pittsfield, Binghamton, and Utica sheets

B) Newark-New York City sheet

Grid Alignment

For purpose of conformity, align the grid such that the upper left corner of the grid (cell A/1) is directly over the upper left (northwest) corner of the IMAGE—not the actual print edge. Let the top of the grid (Letters a,b,c etc.) line up horizontally across the top of the image (the numbers should be off the image). This will allow the grid to align straight across—if done correctly, the lower left portion of the image will be “slivered” off slightly.

Part One: Albany, New York

1) Using the color composite, locate the grid coordinates of the following:

a) Albany, NY

b) Pittsfield, MA

c) Schoharie Creek

d) Tomhannock Resevoir

e) Otsego Lake

f) Little Falls, NY

g) Blue Mountain Lake

h) Bennington, VT

2) a) Referring to the band imagery (4,5, and 7), in which band or bands are the water bodies and drainage patterns best detectable? Why?

b) Locate Interstate 87-90 (use map for reference in necessary) that extends south and east from Albany. Identify the band in which this linear feature is most visible and provide some possible reasons why.

3) a) Identify the land use/land cover at grid cells M-15, 16. Use map for help.

b) At what other gird locations, if any, do you see this type of land cover?

4) Study the imagery (all bands and composite) and map sheets with respect to the following land cover. Describe their general appearance relative to gray tone and brightness levels for each band (e.g. white, light gray, dark gray, mottled, etc.)

FEATURE	BAND 4	BAND 5	BAND 7	COMPOSITE
Urban Areas
Transportation
Vegetation
Water and Drainage

5) a) Which of the images is darkest overall? Why?

b) Which image is lightest? Why?

6) a) Using a piece of mylar or tracing paper, outline the urban areas—be sure to state which band(s) you used for this effort. Compare your polygons with the urban area boundaries found on the maps. Discuss which urban areas are visible and which are not with attention paid to population size differences.

b) Briefly discuss any similarities or differences your overlay may have with the USGS map of the region. (Hint: consider the categories listed in Question 4 for a start.)

Part Two: New York City—New Jersey

1) In the southwest corner of the color composite image, what do you think accounts for the spatially dispersed white “blotches”?

2) Using the color composite again, identify the activity, land cover/land use, or feature found in the following grid cell locations:

a) F-11,12 and G-11

b) L-14 and M-14

c) R-8, S-7, and T-7

d) E-9 and 10 and F-9

e) O-3

f) F-9 and 10

3) Examine the four images and refer to the region mentioned in Question 1. Offer a summary of this region as a whole. Note the overall spectral response of the area and relate it to vegetation, physiography, land cover, etc.

4) Locate grid coordinates U-V-W/3. What are the brighter response areas on the color composite? How does the map classify this location?

5) a) What accounts for the lighter tones in the Hudson River when compared to the spectral response from the oceans?

b) On which band is the river most easily detectable?

c) On which band is the river least detectable?

d) Why?

6) Locate the following features by grid coordinates:

a) Barnegat Bay

b) Navesink

c) JFK Airport

d) Central Park

e) Sandy Hook Lighthouse

f) Flanders Bay

7) Note the temporal differences between the USGS maps and the Landsat MSS imagery. Do you notice any changes that may have taken place during this time period? That is, look at the time when the images were obtained and when the map was produced. Name them.

8) Carefully examine the metropolitan area centered around New York City on all bands and the composite image. Discuss the spectral return characteristics for each of the four images and explain them.