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Question 1

What are 3 advantages of remote sensing data?

Answer 1

1. Improvements over ground-based data collection
2. New measurements available
3. Synergy: lots of measurements able to be taken simultaneously

Question 2

What purpose does ground-based measurements still serve?

Answer 2

They act to calibrate and validate remote sensing data

Question 3

What are the two concepts of remote sensing?

Answer 3

Approach and sensor type

Question 4

What are the 2 approaches to remote sensing?

Answer 4

Active and Passive

Question 5

What are the 2 sensor types to remote sensing?

Answer 5

Imaging and non-imaging

Question 6

Describe the imaging sensor type?

Answer 6

creates a picture by scanning across an array with its ‘swath’

Question 7

Describe the non-imaging sensor type

Answer 7

makes individual point measurements

Question 8

What are the 3 orbital parameters that affect remote sensing satellites?

Answer 8

1. Altitude = defines the speed of orbit
2. Eccentricity = defines the shape of the orbit
3. Inclination = angle at which the sensor crosses the equator

Question 9

What is the low earth orbit

Answer 9

Satellite that remotely senses in the altitude of 400-1000km above earth, around the poles (90 degrees to equator). It achieves a global coverage through repeated strips of orbit

Question 10

What is the geostationary orbit?

Answer 10

Satellite that remotely senses at the altitude of 36,000km, the satellite stays in one position directly over the same position on earth. This means it orbits in time with the earth’s rotation.

Question 11

What are the measurements from the geostationary orbit used for?

Answer 11

Weather and communication satellites.

Question 12

How does altitude affect spatial resolution?

Answer 12

The higher the altitude the lower the spatial resolution

Question 13

What are the 4 types of resolution for remote sensing?

Answer 13

Spatial, temporal, radiometric and spectral

Question 14

What is spatial resolution?

Answer 14

The minimum separation of 2 discrete objects for them to be resolved individually

Question 15

What is commonly used to reference the spatial resolution?

Answer 15

The grid size of the image raster

Question 16

What is temporal resolution?

Answer 16

The ability to pinpoint events in time. Essentially how often time certain measurements are taken.

Question 17

What is radiometric resolution?

Answer 17

The ability of a system to represent and distinguish differences of intensity.

Question 18

How do you describe the mechanics of a computer’s system for radiometric resolution?

Answer 18

Binary

Question 19

How does the radiometric resolution of sensor work?

Answer 19

So the computer’s binary system can be to the power of any number e.g. 2^4. The power then determines how many ‘bits’ which essentially means how many levels of intensity it has. So more bits means that there are more colours/shades that are available to represent things.

Question 20

What is a signed integer?

Answer 20

Means that it can have negative values

Question 21

What is an unsigned integer?

Answer 21

Means that all values will be positive.

Question 22

How does whether something is a signed or unsigned integer affect the range of values in radiometric resolution?

Answer 22

Whether its signed or unsigned determines the range of values for the differing levels of intensity.

Question 23

What value is important to remember when looking at the range of values for the radiometric resolution?

Answer 23

0

Question 24

What is spectral resolution?

Answer 24

The ability to resolve features in the electromagnetic spectrum

Question 25

What features in the electromagnetic spectrum do we most commonly look at?

Answer 25

Visible layers, NIR, SWIR, MICROWAVES

Question 26

What are the categories that make up the electromagnetic spectrum?

Answer 26

Y rays, X rays, UV, Visible Light (blue, green, red), Infra-red, microwave, Radio waves (FM, AM), Long radio waves