On Apr 29, 1:33 pm, (Citizen Bob) wrote:
On Sat, 28 Apr 2007 23:57:06 +0100, "Bernard Burton"

wrote:
Clouds absorb and re-radiate downwards the upwelling long-wave radiation
from the surface. When cloud cover replaces clear sky the surface radiation
continues, but can no longer escape to space. The air temperature near the
surface rises towards the ground temperature until a new balance is
achieved.

But how can that cause a temperature rise?

--

"Perhaps the meek shall inherit the Earth, but they'll do it
in very small plots - about 6' by 3'."
-- Robert A. Heinlein

There is another source of heat - the air some distance
above the ground. On a radiation night this air will be warmer than
that in the lowest layers. If there is any turbulence at all there
will be some downward flux of heat to the lower layers which are no
longer being cooled by contact with the ground. In the case of a flat
calm and a strong inversion this particular mechanism would not work,
but there would still be heat flux from just below the ground surface.

Tudor Hughes, Warlingham, Surrey.