Poznan -- Armed with walnuts, apocalyptic art and a small green dinosaur, environmentalists spiced up the UN climate talks here Monday with colorful demands for action on global warming.

The World Wildlife Fund, or WWF, welcomed the almost 11,000 participants at the 12-day talks in Poznan by handing out walnuts and urging them to "crack the climate nut" and overcome negotiation deadlock.

Greenpeace meanwhile unveiled a three-meter (10-foot) high sculpture depicting the Earth on the brink of destruction from a "tidal wave" of carbon dioxide made of wood and coal.

"So far, there is still an utter lack of any kind of visionary leadership in these talks. There are still governments that repeatedly fail to grasp the urgency of the crisis," Greenpeace said.

"That's why we need to make ourselves heard, because the impacts of climate change are racing ahead of the scientific projections."

It also launched a video running through 20 years of speeches and "broken promises" on climate change from the likes of former German chancellor Helmut Kohl, French President Nicolas Sarkozy and Italian Prime Minister Silvio Berlosconi.

The forum in Poland of the 192-member UN Framework Convention on Climate Change (UNFCCC) comes halfway in a two-year process, launched in Bali, Indonesia, that aims at crafting a new pact in Copenhagen in December 2009.

Delegates in Poland are tasked with whittling down an 82-page document containing a vast range of proposals for action into a workable blueprint for negotiations culminating in a deal in the Danish capital.

As the first day's negotiations wound up, activists staged a "Fossil of the Day" ceremony, handing a symbolic award to Poland for its addiction to coal, the dirtiest fossil fuel.

The "Fossil of the Day" began years ago at the annual UNFCCC meeting as a touch of simple comedy, with the flag of an offending nation planted into a small mound of coal against a pastiche of the "Jurassic Park" movie poster.

In Poznan, though, it snowballed into an Oscar-style ceremony complete with a tuxedoed presenter, who held aloft a silver cup with a green plastic dinosaur on top, with a Polish flag between its claws.

A Canadian campaigner, Katherine Trajan, in dressed in a ballgown, pearls and a fur stole -- "I bought it at the market in Poznan for a few zlotys," she admitted -- sang a special "Fossil of the Day" anthem.

DPA