The invitation to the White House in the spring of 2009 struck Barack Obama's allies in the environmental movement as a big moment: a clear sign that climate change was on his radar and that the president was eager to get to work.

The event was indeed a turning point, but not the one campaigners expected. Instead, it marked a strategic decision by the White House to downplay climate change – avoiding the very word – a decision some campaigners on the guestlist say produced the strange absence of climate change from the 2012 campaign, until hurricane Sandy blew it right back on the political agenda.

The images of a paralysed New York City at the mercy of Hurricane Sandy's wall of water have forced climate change on to the political agenda in the final week of the 2012 presidential election campaign. Even before Sandy made landfall political commentators were debating whether the storm would be better for Mitt Romney or Barack Obama. In any event it has brought forth statements from prominent Democrats and elected officials on climate change and spurred public debate about the neglected topic.

Campaigners said the devastating storm could turn out to be the October Surprise of the elections, exposing Republicans' failure to engage with an issue that is no longer a distant threat, but a present day danger.

The future of low-carbon energy in the UK became a little clearer on Tuesday when a new player entered the nuclear race and the government published a shortlist of four potential carbon capture and storage projects that will compete for funding.

The Japanese industrial company Hitachi has agreed to buy the nuclear consortium Horizon, a former project of the German utilities RWE and E.ON, which they put up for sale when they decided to bow out of UK nuclear energy in March.

Hitachi, which faces a nuclear shutdown in its home market after the Fukushima incident last year, will pay £700m and hopes to construct up to four nuclear reactors across the country. Horizon plans new reactors at Wylfa on Anglesey, north Wales, and Oldbury in Gloucestershire.

One of the world's leading naturalists has accused US politicians of ducking the issue of climate change because of the economic cost of tackling it and warned that it would take a terrible example of extreme weather to wake people up to the dangers of global warming.

Speaking just days after the subject of climate change failed to get a mention in the US presidential debates for the first time in 24 years, Sir David Attenborough told the Guardian: "[It] does worry me that most powerful nation in the world, North America, denies what the rest of us can see very clearly [on climate change]. I don't know what you do about that. It's easier to deny."