Greenhouse Effect and Climate Change

Nobody doubts that the planet is undergoing a greenhouse effect. The atmosphere is polluted and the result is the surface of the planet is heating up.
Nobody doubts that the climate is changing. El Nino is an explanation that has gone past it's use by date.

The critical question is "Is global warming causing climate change?"

The answer isn't clear. There are scientists who will argue against a link and scientists who will tell us there is a link. Who is correct?

The failure of governments to enact any significant response to this problem is twofold.
First there is no unanimous scientific opinion or overwhelming scientific evidence.

Second, governments have a short term outlook, they can't see beyond the next election.
Any policy that is designed to tackle the greenhouse effect, assuming this is in fact causing climate change, would be a long term policy.

The pressure is on the scientists to come up with data, and come to an agreement on this issue, otherwise politicians will continue to drag their feet.