A free press is the immune system of representative democracy.

The struggle against poverty in the world and the challenge of cutting wealthy country emissions all has a single, very simple solution... Here it is: Put a price on carbon.

Earlier in this century, the Heisenberg Principle established that the very act of observing a natural phenomenon can change what is being observed. Although the initial theory was limited in practice to special cases in subatomic physics, the philosophical implications were and are staggering.

We now face the prospect of a kind of global civil war between those who refuse to consider the consequences of civilization's relentless advance and those who refuse to be silent partners in the destruction. More and more people of conscience are joining the effort to resist, but the time has come to make this struggle the central organizing principle of world civilizations.

The message from Wal-Mart today to the rest of the business community is there need not be any conflict between the environment and the economy. We will find the way not only to reconcile (those), but to find new profits and new opportunities as we do the right thing.

I have felt for a long time that the pathway to solving the climate crisis is through the building of a massive grassroots army of men and women who will go out there and win the conversation on climate, and persuade businesses, and universities, and towns to switch to renewable energy and to reduce emissions. And the big change from ten years ago is that people are way more receptive, not only to the message that we have to act, not only to the message that now we can act, we have the solutions now - that's the biggest change - but also willing to make a commitment that we will act.

Some of the most intriguing new research is in the area of extreme weather events and rainfall. A recent study by German scientists published in Climatic Change projects that extreme precipitation will increase significantly in regions that are already experiencing extreme rainfall. Man-made global warming has already increased the moisture content of the air worldwide, causing bigger downpours. Each additional degree of temperature increase causes another seven percent increase in moisture in the air, and even larger downpours when storm conditions trigger heavy rains and snows.