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UK scientists have detected a huge dome of freshwater that is developing in the western Arctic Ocean. The bulge is some 8,000 cubic km in size and has risen by about 15cm since 2002. The team thinks it may be the result of strong winds whipping up a great clockwise current in the northern polar region called the Beaufort Gyre. This would force the water together, raising sea surface height, the group tells the journal Nature Geoscience.

The data (1995-2010) indicates a significant swelling of water in the Beaufort Gyre, particularly since the early part of the 2000s. The rising trend has been running at 2cm per year.

A lot of research from buoys and other in-situ sampling had already indicated that water in this region of the Arctic had been freshening. This freshwater is coming in large part from the rivers running off the Eurasian (Russian) side of the Arctic basin. Winds and currents have transported this freshwater around the ocean until it has been pulled into the gyre. The volume currently held in the circulation probably represents about 10% of all the freshwater in the Arctic.

Surface temperatures in the Arctic since 2005 have been higher than for any five-year period since record keeping began in 1880, according to a new report from the Arctic Monitoring and Assessment Program, an international group within the Arctic Council that monitors the Arctic environment and provides advice on Arctic environmental protection.

The rate of sea-ice decline has accelerated and the decline rate in the past 10 years has been higher than the Intergovernmental Panel on Climate Change predicted in 2007, the report says.

Dramatic and unprecedented plumes of methane – a greenhouse gas 20 times more potent than carbon dioxide – have been seen bubbling to the surface of the Arctic Ocean by scientists undertaking an extensive survey of the region.

The scale and volume of the methane release has astonished the head of the Russian research team

never before witnessed the scale and force of the methane being released from beneath the Arctic seabed.

Fresh snow bounces back 84 percent of the light that hits it; warm, rounded crystals can reflect as little as 70 percent. Slushy snow saturated by water – which gives it a gray cast, or even a bluish tint – reflects as little as 60 percent. Add dust or soot, and the albedo drops below 40 percent. Box's satellite data has shown a steady darkening in Greenland's albedo, from a July average of 74 percent when the century began to about 68 percent last year. And then came this summer: Without warning, the line on the albedo chart dropped deep into uncharted territory. At certain altitudes, the ice sheet in Greenland was suddenly four percent less reflective – in a single season.

But the future, pressing as it is, sometimes gives way to sheer awe at the scale of what we've already done. Simply by changing the albedo of the Greenland ice sheet, Box calculates, the island now absorbs more extra energy each summer than the U.S. consumes in a year. The shape and color of the ice sheet's crystals, in other words, are trapping more of the sun's rays than all the cars and factories and furnaces produce in the world's biggest economy. One of Box's collaborators, photographer James Balog, puts it like this: "Working in Greenland these past years has left me with a profound feeling of being in the middle of a decisive historic moment – the kind of moment, at least in geologic terms, that marks the grand tidal changes of history." Amid this summer's drama of drought, fire and record heat, the planet's destiny may have been revealed, in a single season, by the quiet metamorphosis of a silent, empty sheet of ice.

A troubling trend has emerged recently: Wildfires are increasing across much of the north, and early research suggests that extensive burning could lead to a more rapid thaw of permafrost.

Thawing has been most notable at the southern margins. Across huge areas, including much of central Alaska, permafrost is hovering just below the freezing point, and is expected to start thawing in earnest as soon as the 2020s.

"And what we want do," says John Sauven, who is executive director of Greenpeace UK, "is say that this area, which is currently not national territory, this area of sea ice around the North Pole, should be a 'global commons', collectively owned by humanity under the auspices of the United Nations.

So now Greenpeace, Mr Sauven says, is planning a global campaign to make the North Pole off-limits. Internalionalised. No development. No oil drilling. No territorial claims

It has done so by its own form of protest, by being present (often at considerable personal risk) at the sharp end of all these situations, and making the world aware: it is the idea of "bearing witness", from the Quaker background of some its founders.

Methane is 21 times more heat-trapping that carbon dioxide.

Actually, any CH4 released today is at least 56 times more heat-trapping than a molecule of C02 also released today. And because of the way it reacts in the atmosphere, the number is probably even higher, according to research conducted by  Drew Shindell , a scientist at NASA’s Goddard Space Center.

And we appear to be approaching some irrevocable tipping points that will create powerful negative feedback loops, the most worrisome being  the release of methane  stores at the bottom of the ocean and locked into sub-Arctic permafrost.