Does man regulate the Earth's climate?

I just found a very interesting site (by accident), and present two quotes from it about the climate and its warming (which some still stubbornly declare is man-made):

In 2004 a group of UNIS geology students found an ancient polar bear jawbone at Svalbard. Now it turns out that this find could confirm that polar bear as a species has already survived one interglacial period, bringing hope that the first and foremost Arctic symbol can – in fact – also survive the current warming climate.

Second quote:

The greatest problem for the International Panel on Climate Change (IPCC) is that they fail to agree on what will happen to the world itself, he told the audience at UNIS. – The planet is itself taking part in the global warming, as the tundra regions emit more CO2 because of increasing temperatures. This is a non-stoppable process from one stable state of the Earth to another stable state; from a cooler climate to a warmer climate, like the ones in the past, Lovelock said.

Both quotes from the website of the University Centre in Svalbard.

What can we learn from this? First of all, polar bears can adapt to changes in the climate's temperature. Second, perhaps there is such a thing as a self-regulating mechanism in Earth's atmosphere, which adjusts when for example volcanoes erupt, leaves rotten and men drive cars fueled by oil.

Doomsday prophesies and socialism are therefore not requested at this time!