Dr James Hansen. Photograph: Gareth Fuller/PA

“You are choosing the path focused on corporate greed,” climate scientist James Hansen has told carbon traders in a open letter which he and climate activists attempted to deliver to a carbon trading conference in New York today.

In below-freezing temperatures, climate change campaigners gathered at midday at the Irish Hunger Memorial in Vesey Park, near the Embassy Suites Hotel where the conference is being held, to hear Hansen read parts of his open letter. Tomorrow there will be another demonstration at the same spot, at which an unconfirmed number of activists have pledged to commit acts of nonviolent civil disobedience.

Brazil’s President Lula addresses the Copenhagen summit. Photograph: Bob Strong/Reuters

One month after the Copenhagen climate summit ended in recriminations and and a weak outline of a global deal, key groups of developing countries will meet to try to explore ways to get to agree a legally binding final agreement.

As the dust settles on the stormy Danish meeting, environment ministers from the so-called Basic countries – Brazil, South Africa, India and China – will meet on January 24 in New Delhi. No formal agenda has been set, but observers expect the emerging geopolitical alliance between the four large developing countries who brokered the final “deal” with the US in Denmark will define a common position on emission reductions and climate aid money, and seek ways to convince other countries to sign up to the Copenhagen accord that emerged last month.

The average American consumes more than his or her weight in products each day, fuelling a global culture of excess that is emerging as the biggest threat to the planet, according to a report published today. In its annual report, Worldwatch Institute says the cult of consumption and greed could wipe out any gains from government action on climate change or a shift to a clean energy economy.

Erik Assadourian, the project director who led a team of 35 behind the report, said: “Until we recognise that our environmental problems, from climate change to deforestation to species loss, are driven by unsustainable habits, we will not be able to solve the ecological crises that threaten to wash over civilisation.”

The world’s population is burning through the planet’s resources at a reckless rate, the US thinktank said. In the last decade, consumption of goods and services rose 28% to $30.5tn (£18.8bn).

This bright green ‘flying frog’ was newly discovered in the eastern Himalayas in 2007. Photograph: HO/AFP/Getty Images

Starting Monday, celebrations and events across the world will highlight the beginning of the UN’s Year of International Biodiversity and the loss of our richly varied flaura and fauna, which is estimated to be as high as 1,000 times the natural rate as a result of human activities.