This link recently discovered says NO.
Where are physicists to comment?
First comment received pointed me to this link:
Meanwhile (it's now 06 OCT 11) more links have turned up from helpful readers, and my thanks to them:
BUT there is a greenhouse effect on Venus!
See Michael Hammer's post at
PS: on 06 AUG 2015:
On Earth, in any case, any CO2 consideration is so trivial that's downright irrelevant, as shown in http://cleanenergypundit.blogspot.co.uk/2014/06/eating-sun-fourth-estatelondon-2009.html