Top news: Nitrogen injected into Fukushima’s reactor 1 to avert potential explosion; proposal to reduce global temperatures by “whitening clouds” could actually increase global warming; Arctic freshwater melt set to flood into ocean, disrupting Gulf Stream; Greenpeace protests against palm oil company’s greenwash; world’s first showjumping cow.

#Nuclear: TEPCO, the owner of Japan’s crippled Fukushima nuclear plant, has started injecting nitrogen into reactor 1 in an effort to reduce the risk of a hydrogen explosion inside the containment. A spokesman for the Japanese government’s nuclear agency described the injection as a “preventive measure”, and denied that there is any “immediate danger”. A build-up of the highly hydrogen gas has caused explosions in three reactor buildings since the earthquake on March 11. The injection process is expected to take six days, and could be later extended to reactors 2 and 3.

#Climate: Scientists debating methods of climate engineering – techniques to manipulate natural processes to counteract the effects of global warming – have warned that some “technical fixes” may do more harm than good. A proposal to whiten clouds by spraying them with seawater suggested that this would cool the earth by reflecting heat from the sun back into space – but a new study shows that using the wrong size water droplets would lead to warming, not cooling. Back to the drawing board!

#Climate: Meltwater from the Arctic icecap is likely to flood into the Arctic Ocean, causing unpredictable changes to the climate in Europe and North America. This huge volume of freshwater - at least twice the size of Lake Victoria in Africa – could influence ocean circulation, potentially cutting of the Gulf Stream which carries heat from the equator towards Europe. Laura de Steur, an oceanographer at the Royal Netherlands Institute for Sea Research, said: “The volume of water discharged into the Arctic Ocean, largely from Canadian and Siberian rivers, is higher than usual due to warmer temperatures in the north causing ice to melt.” Scientists are unable to predict when this might happen, or the speed at which the effects could be felt.

#Forests: Activists from Greenpeace Australia got up to a bit of monkey business outside Asia Pulp and Paper (APP)’s “certification workshop” in Sydney, to expose the company’s greenwashing agenda. Dressed as endangered orangutans, whose rainforest habitat is being destroyed by companies including APP, the activists held placards reading “APP – a great peril to your brand”.

“APP, and its affiliate in Australia, Solaris, are not only forest destroyers, they’re also brand destroyers,” said Reece Turner, a Greenpeace forests campaigner. “With a track record of greed and greenwash and a long list of abandoned contracts, Australian companies would be wise to buy their pulp and paper products elsewhere.”

#Animals: Like many kids, Regina Mayer was told that she couldn’t have a horse. But, unlike most kids, she came up with an ingenious solution: train a cow to ride instead. Now, Regina’s cow Luna will even jump over obstacles like a proper showjumper. But don’t try this at home: the Royal Society for the Prevention of Cruelty to Animals (RSPCA) says: “Riding a cow is definitely not something we’d recommend.”

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