evidence: Climate change: The 'insane' plan to save the Arctic's sea-ice [...] As sea-ice vanishes, the dark ocean surface can absorb more of the Sun's energy, which accelerates warming. So the researchers want to thicken it to stop it melting away. [...] The Arctic Ocean is likely to be effectively free of sea-ice by the end of summer at least once by 2050, and possibly even sooner. As the graph below shows, it's already experienced steep declines since the 1980s.