Some Mostly Common-Sense Properties of
Features on GOES Weather-Satellite Images

Using some common sense, plus information available in assigned reading from Chapter 2 of our text and in the handout "Weather Satellite Images", you should be able to answer the questions below. [Note: answers are provided.]

(1) What four broad categories of features are generally visible on GOES weather-satellite images?

(2) Below, categorize the four features above according to their typical relative albedo and temperatures. (In some cases you will want to consider time of year, time of day, altitude, elevation, or latitude. For example, high-altitude land surfaces are generally relatively cold compared to low-altitude land, all else being equal.)

Features Typically with a Relatively High Albedo Features Typically with a Relatively Low Albedo
Cloud tops

Snow/ice surfaces

Land surfaces (though vegetated areas generally have significantly lower albedo than unvegetated areas, such as deserts, do)

Ocean surfaces (which generally have the lowest albedo of all; when the angle between the ocean surface and the sun is just right, the ocean will reflect most of the light striking it, but that's the exception rather than the rule)

Features Typically with a Relatively High Temperature
Features Typically with a Relatively Low Temperature

Snow/ice surfaces
Land surfaces at low elevations <--> Land surface at high elevations
Land and ocean surfaces
at low latitudes
<--> Land and ocean surfaces
at high latitudes
Land surfaces
in early/mid afternoon
<--> Land surfaces near sunrise
[Land surfaces in mid/late summer <--> Land surfaces in mid/late winter]*
[Ocean surfaces in late summer <--> Ocean surfaces in late winter]**

(* Seasonal variations are generally much more pronounced at high latitudes that at low latitudes. The tropics do experience moderate seasonal variations, especially in rainfall, but they do not have the typical four seasons that we in the midlatitudes tend to think are standard everywhere.

(** Seasonal variations in ocean surface temperatures are generally much smaller than they are for land surfaces, but they can still be significant--say, for determining when hurricanes/typhoons/tropical cyclones occur.)