We do not know if scientists say exactly the same thing as Gore or if the consensus position is a simple majority or a unanimous position among scientists.
Reading what real climate scientists say reveals how different their tone is in comparison to how Gore represents their views. Al Gore has hijacked the scientific dialogue, making it political and difficult for researchers to question each other's work.
Getting labeled a heretic
Expressing doubt gets one labeled a heretic. The scientific method depends on a dialogue among scientists that is unconstrained and independent of politics.
From my reading, a plurality of scientists actively engaged in basic climate research would agree with the following: The world's climate is getting warmer. When you consider the natural variability of global climate it is still clear that a significant part of the warming is manmade (anthropogenic). However, global climate is a chaotic system and it is impossible to forecast chaotic systems further than a few weeks in advance.
Therefore, the best we can do is run simulations in an effort to see what the risks might be. Some of those simulations are quite alarming, others are not. The simulations are based on a phenomenal amount of computer code and our knowledge of the complex systems they are trying to model is far from complete.
This is where the "consensus" ends.
There is considerable disagreement about what an optimal climate change policy should look like. People who study this issue agree we should do something. We need calm but vigorous debate about our response, since anything we do will have an opportunity cost.
One group of scientists directly engaged in climate research suggested we should treat global warming like an insurance problem. We face a distant probability of a truly catastrophic loss; therefore, our response should be to adopt policies to insure us against that event. Al Gore and his supporters tell us scientists uniformly believe it is a certainty we will suffer a catastrophic loss. That is not true.
What do we do?
If global warming is an insurance problem, what do we do? First, we take reasonable actions to postpone the critical date by reducing our greenhouse gas emissions. Second, we support research on basic climate science. Third, we support research on new technologies for alternative energy and we explore technologies to deal with global warming.
We should do all of these things simultaneously, since they give us more time and flexibility to deal with the problem. It is like insuring your house against loss by fire. The prudent person installs fire alarms, keeps fire extinguishers close at hand, removes fire hazards, and buys insurance. Buying insurance means forgoing a small amount of consumption each year in order to protect one from catastrophic loss. You do not take extreme measures that have unintended consequences.
The global warming crusade seeks to pound skeptics into submission. Demonizing people who have reservations makes it less likely we can achieve a compromise.
Bob Martin is the Ewing T. Boles Professor of Economics at Centre College.