On Saturday, August 8, 2015 at 10:14:21 AM UTC+1, Len Wood wrote:
On Saturday, 8 August 2015 00:25:04 UTC+1,

Alastair,
It is net cooling by radiation you are talking about, as some on this thread have hinted.
You can call it cold radiation if you like, but that is not very scientific despite you finding it at odd places in the literature.

No, in that case, I am calling the absorbed radiation cold radiation. The net radiation is the emitted less the absorbed. Hence the object will cool.

On a clear calm night a land surface cools by radiation.
It loses more heat than it absorbs. Presumably you are calling this cold radiation.

It cools because the absorbed radiation is colder than that which it is emitting.

During a sunny day a land surface warms by radiation. Presumably you want to call this warm radiation.

A better name for solar radiation would be hot radiation rather than warm. If you call it warm then I should call my cold radiation cool.

Cold bodies radiate, but your body only feels cold because you are radiating more heat than you are absorbing from the cold body. Net cooling by radiation again.
There is no real need to talk about warm or cold radiation.

Agreed, but if you call the radiation emitted by cold bodies cold radiation then it makes sense to say that it will cool a warmer body which absorbs it.