Clouds

How to recognise them and be wiser for it

Today’s menu

• Discussion

• Some clouds

• More clouds

Clouds: visible

• Clouds appear bright

• Thicker clouds are brighter (greater optical depth)

• Clouds with more water (or ice) content are brighter

Cloud activity

• How can we tell different cloud types from one another?

From VIS

• Brightness

• Shape (and changes in shape)

• Texture

• Motion

Texture

Using IR

• Temperature– Related to height

• Change in temperature– Related to change in height

• Shape

Fronts - Vis

Fronts - IR

Lots of clouds

• Fronts have all kinds of clouds and we can compare the Vis and IR to tell one from the other

• Low Sc are dark on the IR but fairly bright on the Vis

• Ci are bright (cold) on the IR, but less distinctive on the Vis

More info

• Lots more detail on the Vis – higher resolution

• Vis has good contrast between cloud and sea, while IR has contrast between cloud and land (at the time of year shown in particular)

• And there was Ac in there too

Here’s some visible Ci

Here comes the big picture

• What do you see?

Low clouds

To the computer room

• GARP