An iceberg near Australia’s Macquarie Island, 1,000 miles south of Tasmania. ­Hundreds more are heading north. Photograph: Jason Ahrens/AFP/Getty Images

A flotilla of hundreds of icebergs that have broken away from Antarctic ice shelves is drifting toward New Zealand and poses a risk to ships in the south Pacific Ocean, maritime authorities have warned.

The area is not a major shipping lane and few sailors are out in November – spring in the southern hemisphere – but ships that traverse the area have little hull protection.

An official navigation warning for the area south of New Zealand is “an alert to shipping to be aware that these potential hazards are around and to be on the lookout,” Maritime New Zealand spokeswoman Sophie Hazelhurst said.

Research and rationalism: ice core drilling on the summit of Quelccaya ice cap, Peru. Photograph: Peter Essick/Getty

I have seldom felt so alone. Confronted with crisis, most of the environmentalists I know have gone into denial. The emails hacked from the Climatic Research Unit (CRU) at the University of East Anglia, they say, are a storm in a tea cup, no big deal, exaggerated out of all recognition. It is true that climate change deniers have made wild claims which the material can’t possibly support (the end of global warming, the death of climate science). But it is also true that the emails are very damaging.

The proposals on emissions cuts are still below those put forward by the EU. Photograph: EPA

The White House said today it would go to the Copenhagen climate change summit with a proposed target for reducing greenhouse gas emissions after facing international pressure to commit to stronger action on climate change.

An administration official told reporters that President Barack Obama would propose the targets before the climate meeting, which is less than three weeks away. The move removes the biggest obstacle to a political deal at Copenhagen.