Chapter 21 - Remote Sensing

Question 1

What are the 2 types of satellite?

Answer 1

Geostationary

Polar orbiters

Question 2

What are the features of a geostationary satellite?

Answer 2

35000km above equator

Equatorial orbit of 24hrs

Good coverage at low lat

Poor coverage at high lat

Easy to create video loops

Poor resolution.

Question 3

What are the features of a polar orbiting satellite?

Answer 3

850km orbit (low orbit)

Sun synchronous (remains at the same angle to the sun)

High resolution

Good coverage at poles

Poor coverage at low lats

Question 4

What are the 3 channels used by satellites?

Answer 4

IR

Visible

WV

Question 5

What are the features of the IR satellite channel?

Answer 5

Recieves information from clouds/earth/dust

Intensity is proportional to T^4

Good at showing cold clouds and can be used 24hrs a day

Poor at showing stratus, fog etc as they will be similar temperature as the ground.

Question 6

What are the features of the visible satellite channel?

Answer 6

Detects insolation reflected back from terrain (relys on albedo)

Good at showing stratus, fog and thick cloud

Can show structure of objects due to shadows

Poor at showing thin cloud and can’t be used at night.

Question 7

What are the features of the WV satellite channel?

Answer 7

It is the same as IR channel but at a frequency that is absorbed by water vapour

It misses terrestrial radiation.