The Obama administration faces a stiff test of its environmental credentials in deciding whether to approve a pipeline carrying greenhouse gas-intensive oil sands fuel from Canada into the US. Hillary Clinton, secretary of state, has the job of deciding whether to approve a 1000-mile pipeline designed to carry up to 800,000 barrels a day from Canada’s vast oil sands – which would, critics say, lock the US into old high-carbon energy instead of turning green.

Wild salmon are returning up the Seine to the French capital for the first time in almost a century, thanks to a major clean-up of the river – including a purification plant - over the past 15 years. The salmon aren’t alone; some 32 species of fish have been seen visiting Paris, including trout, shad and lamprey eels.

Achieving the broad goals put up to limit climate change may cost the world $300 billion per year: $200 bn for mitigation and another $100 bn for adaptation, says UN climate head Yvo de Boer. A large amount, true; but reflect the US stimulus package to revitalise the economy alone was worth $787 billion.

Carbon capture and storage: a sustainable solution or expensive pipe-dream? This Washington Post backgrounder takes a look at how the coal industry is investing in this as-yet unproven technology – and what the results might be.

Odd Spot: When is a wetland a burst water main? When you’re busy building a new Pan-African Parliament on top of it. But having “discovered” their error once building started, South Africa to their credit have stopped site-work to try to preserve what they can of the swamp.

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