Police horses with eye covers stand in a park as the force guards a demonstration in Copenhagen. (Reuters)

Goal 350

Hundreds of church bells across the globe, including Copenhagen, tolled 350 times on Sunday, beginning 3.50pm in their local time zones, symbolically calling out for efforts to stop climate change. Many scientists say 350 parts per million is the upper level of a safe concentration of CO2 in the atmosphere.

“It’s the most important number in the world,” said Bill McKibben, founder of environmental group 350.org. “It’s the line between habitability on this planet and a really, really desolate future.”

Not everyone accepts that, but an entire environmental group has sprung up around the number, sporting 350 on T-shirts and flags. About 100 nations at the UN climate summit have signed on to the idea of heading for 350.

The last time Earth had 350ppm of CO2 in the air was in the autumn of 1989. This year, CO2 pushed over 390ppm. When scientists started measuring CO2 in 1958, it was 315ppm

Cars burnt

Arsonists torched over a dozen cars in Copenhagen on Monday, including nine belonging to DONG Energy, just hours ahead of a planned protest against the state-owned utility. DONG, which gets most of its power from coal-fired plants, last week cancelled plans to build its first coal-fired power station in Germany, saying it no longer believed the project had the necessary backing. Vandals also smashed windows and threw red paint at the headquarters of the Danish Immigration Service. On Sunday, police arrested dozens of anti-capitalist protesters as around 200 people tried to block a section of Copenhagen’s port on the sidelines of UN climate talks

City summit

Some 80-odd mayors and city officials have converged in Copenhagen for a five-day “city summit” parallel to the UN climate conference. They’ll compare notes on how cities can combat climate change and save money on energy and other costs.

Today’s cities and towns consume two-thirds of the world’s total primary energy and produce more than 70 per cent of its energy-related CO2 — a figure expected to reach 76 per cent by 2030. Most comes from electrifying and heating private, commercial and municipal buildings.

But the cities face many obstacles to becoming more “climate friendly” — from extensive old infrastructure that would cost too much replace, to political interests that resist plans to, say, make energy audits compulsory or a fee for driving into congested city centres.

The mayor of Copenhagen, where a third of commuters use bicycles, has her problems, too: finding enough parking space for all those bikes

Forest flop

Former US Vice-President Al Gore at a meeting of cabinet ministers from Nordic countries in Copenhagen. (AP)

A proposal aimed at saving the world’s tropical forests suffered a setback on Sunday when negotiators ditched plans for faster action because of concerns that rich countries aren’t willing to finance it.

Destruction of forests — burning or cutting trees to clear land for plantations or cattle ranches — accounts for about 20 per cent of global emissions. That’s as much CO2 as all the world’s cars, trucks, trains, planes and ships combined.

So a deal on deforestation is considered a key component of the pact being negotiated in Copenhagen. On Sunday, language calling for reducing deforestation by 50 per cent by 2020 was struck from the text.

“We are still on our way to destroy an area the size of India by 2017,” said Gro Harlem Brundtland, UN special envoy for climate change