Farewell and thanks for reading

This is my last entry for this page - I'm leaving the BBC to work, initially, on ocean conservation issues.

While this page will no longer be updated, it will stay here for reference.

I hope you've enjoyed reading my blog down the years - I've enjoyed writing it, and have appreciated your comments.

To keep up to date with news and views about the environment, I hope you'll keep reading the science and environment pages of the BBC News website, the thoughts of my successor Matt McGrath, and my science correspondent colleagues Jonathan Amos and David Shukman.

Read full article Farewell and thanks for reading

Geoengineering: Risks and benefits

Model cloud whitening ship
Image caption Cloud-whitening - geoengineering, or not?

Few issues arouse as much controversy in environmental circles these days as geoengineering - "technical fixes" to tackle climate change, by sucking carbon dioxide from the air or by reducing the amount of sunlight hitting the Earth.

And here's why.

Read full article Geoengineering: Risks and benefits

Climate: 2C or not 2C?

Anti-climate tax protestor
Image caption Climate "sceptics" are making it hard for the US and other governments to progress

Comments by the US climate envoy last week discussing the value of the 2C target in international climate change negotiations have provoked quite a response.

Todd Stern, who leads the US negotiating team in the UN climate convention (UNFCCC) and performed the same role at the recent Rio+20 summit, told an audience at Dartmouth College that insisting on the target in negotiations would lead to "deadlock".

Read full article Climate: 2C or not 2C?

Climate science and acts of creation

James Hansen
Image caption Prof Hansen argues climate change is "loading the dice" of extreme weather

The role of formal scientific processes in climate science appear to be under threat as never before.

Last year, physicist Prof Richard Muller and colleagues published - in the sense of posting material on their website - results from a new project analysing the Earth's temperature record.

Read full article Climate science and acts of creation

Rio revisited: Glass half-full?

Dilma Rousseff speaking in Rio
Image caption Brazilian President Dilma Rousseff attended a very successful summit

A couple of weeks back I chaired a debate at Chatham House, the London-based think tank, on a question that I'd been asking myself for a while.

Rio+20: Green Growth or Greenwash? was the title.

Read full article Rio revisited: Glass half-full?

'ClimateGate': Case closed?

Prof Edward Acton, UEA vice chancellor, and detective chief superintendent Julian Gregory of Norfolk Constabulary
Image caption Prof Edward Acton, UEA vice chancellor, and detective chief superintendent Julian Gregory of Norfolk Constabulary

Will we ever know who hacked the "ClimateGate" files, and why?

Probably not, judging by the insights gained by the Norfolk police force during their two-and-a-half-year investigation, which they've just closed.

Read full article 'ClimateGate': Case closed?

Fukushima's disease risk: A major fallout?

Children playing in waves
Image caption Nakoso beach, 65km south of Fukushima Daiichi, opened for holidaymaking this week

What claims to be (and indeed appears to be) the first formal attempt to calculate numbers of cancer cases and deaths resulting from the Fukushima nuclear accident has just been published.

The Energy and Environmental Science journal paper calculates that total deaths will lie in the range 15-1,300, while cases will number 24-2,500.

Read full article Fukushima's disease risk: A major fallout?

Whaling moves beyond the harpoon

The baiji or Yangtze River dolphin
Image caption The baiji, or Yangtse River dolphin, is thought by experts to have died out

The most common question I get asked after International Whaling Commission (IWC) meetings is simple: "What did it do for whales?"

Often, the answer has been: "very little". But at this year's meeting in Panama City, things were a little different.

Read full article Whaling moves beyond the harpoon

Whales snared in ocean debris

A whale entangled in a shark net off Australia's Gold Coast

How many whales are snared and killed by fishing gear and ocean debris each year? No-one knows for sure - but the number entangled is probably huge, and the number dying significant.

Over the past few years, the International Whaling Commission (IWC) has been starting to address this issue more seriously than before.

Read full article Whales snared in ocean debris

South Korea's whaling: Faux and cons

Activists protest at the IWC in Panama City
Image caption Activists protest at the IWC in Panama City

This is the eighth meeting of the International Whaling Commission (IWC) that I've covered; so I'm always a bit chary of the possibility that over time I've become a more grumpy, wizened, curmudgeonly old cynic than the organisation's politics might merit.

So it's been refreshing to chat with a few first-timers this year - and confirmatory that some of them, after just three days of what's been a functional meeting by recent standards, already find the waters of hypocrisy and selective memory running deep and strong.

Read full article South Korea's whaling: Faux and cons