Exam 2

Question 1

What is active remote sensing?

Answer 1

Using radio, sound, or light waves to collect data by allowing them to bounce off of an object and reflect back to a receiver. LiDAR, Sonar, and weather Radar

Question 2

What is passive remote sensing?

Answer 2

Collecting data via images

Question 3

What is spatial resolution?

Answer 3

Smaller pixels provide more information

Question 4

What is spectral resolution?

Answer 4

More bands or wavelengths yield more information

Question 5

What is geosynchronous orbit satellites?

Answer 5

Yield lots of low quality images of 1 location that are taken from a higher altitude.

Question 6

What are Sun synchronous orbit satellites?

Answer 6

Fewer high quality images of many locations that are taken from lower altitude.

Question 7

What data does LIDAR collect?

Answer 7

Elevation data, vegetation cover/biomass, uses light waves to collect data, and is an example of active remote sensing

Question 8

What is NDVI

Answer 8

Indicates healthy and unhealthy vegetation by comparing reflection of near infrared and red light

Question 9

What does healthy vegetation do?

Answer 9

Reflects more near infrared light

Question 10

What does unhealthy vegetation do?

Answer 10

Absorbs more near infrared light

Question 11

What are Lindsay images?

Answer 11

Multispectral imagery with high spectral resolution

Question 12

What is change detection wizard?

Answer 12

Analyzes differences in overlapping pixels from multiple raster layers

Question 13

What is select by attribute?

Answer 13

Uses logical statements to identify a subset from a vector dataset

Question 14

What is discrete data?

Answer 14

A surface made of raster cells that shows a distinct and discernible region on a map

Question 15

What is an example of discrete data of a surface?

Answer 15

Soil types in an area

Question 16

What is continuous data?

Answer 16

Smooth transitions between the variation of the data

Question 17

What is an example of continuous data?

Answer 17

Elevation data

Question 18

What does the clip tool do and why do we use it?

Answer 18

Creates a new layer based in intersection of 2 vector datasets

Question 19

What is remote sensing in general?

Answer 19

A way of measuring environmental properties without direct contact

Question 20

What can LIDAR be used for?

Answer 20

Mayan cities were discovered by being able to strip off the trees and see beneath them

Question 21

What does Google maps use, passive or active remote sensing?

Answer 21

Passive because tells us precipitation, water temperature etc

Question 22

What is a buffer

Answer 22

Creates polygons around vector data to create a perimeter or specified distance around the vector dataset

Question 23

Join field

Answer 23

Adds data to attribute tables from another attribute table based on some common field

Question 24

Change detection wizard

Answer 24

Analyzes differences in overlapping pixels from multiple raster layers change overtime in raster data

Question 25

Temporal resolution

Answer 25

High resolution- many samples over time

Question 26

Ground truthing

Answer 26

A way to verify remotely sensed data

Question 27

Benefits and drawbacks of raster data

Answer 27

Pro- equal sized pixel. Each pixel has numerical data. Can stack data to be seen on one layer Con- very large file slow processing time

Question 28

Euclidean distance

Answer 28

Straight line between 2 points based on a triangle. Considered the hypotenuse

Question 29

In terrain analysis, what is aspect?

Answer 29

Tells us what slope is facing in what direction so tells us what plants and animals face the sun.

Question 30

Which one is generally cooler. East or west facing slope

Answer 30

East

Question 31

Aspect tells us what

Answer 31

Slope, water content, amount of sun exposure

Question 32

What is DEM? How do we use it

Answer 32

Digital Elevation model that is associated with raster data. Mostly from LiDar data. Helps Provide us with information about slope, elevation, hillshade, aspect, and angles

Question 33

Interpolation

Answer 33

Takes point data and uses it to estimate the value for another location

Question 34

When and why we use interpolation

Answer 34

Temperature data can be assumed and it uses Euclidean distance to determine which points are nearest to each other.

Question 35

What is slope how to calculate it

Answer 35

Angle of topography measured in slope ratio.

Question 36

Suitability analysis steps

Answer 36

1. Collect source layers 2. Reclassification 3. Create suitability layers 4. Calculate weighted overlay