The setting midnight sun lights calving icebergs and resulting massive wave at face of Eqip Glacier in Disko Bay, Greenland, on summer evening.

Light glistens on melting icebergs in Greenland.

Petermann’s floating ice tongue has been disintegrating during this recent period of warming, losing 250 sq. km since 2000.

The ice island that calved off the Petermann Glacier in northwestern Greenland in 2009 continued its slow migration down the fjord. Although slivers of ice have loosened around its edges, the ice island has largely retrained its original shape.

A mother polar bear (Ursus maritimus) and two cubs stand on pack ice, North East Greenland Coast, Greenland, Arctic.

The midnight sun lights massive iceberg grounded near face of Jakobshavn Isfjord in Greenland, on a stormy evening.

Greenland’s contribution to sea-level rise has doubled during this century alone. Some glaciers in Greenland’s south-east have doubled, even tripled, their flow speed to 38m a day in the past six years. In comparison, most alpine glaciers move, on average, about 50m a year.

Southern tip of Greenland.

The Petermann Glacier, among the largest in the northern hemisphere, lies above the 80th parallel in Greenland’s northwest. It’s an outlet glacier and it flows NNW from the inland ice of Knud Rasmussen Land to the coast.

A high arch forms in the giant icebergs At Ilullissat, Disko Bay, Greenland.

An aerial View Arctic Fjord Coast, Greenland.

It’s not the annual thaw that worries scientists. It’s the growing discrepancy between the yearly accumulation and loss of ice – known as the mass balance – that’s causing concern. There isn’t enough snow falling on Greenland’s icecap to replace the recent increase in icebergs calving into the sea.

An ice penetrating radar is deployed from a string of kayaks to survey a section of the Petermann glacier. Three scientists fit a radar transmitter, receiver and antennas to a chain of four kayaks, to obtain valuable data on the processes operating over floating ice shelves.

The ‘ice bridge’ is the southernmost extent of the summer sea ice, which usually extends much further south into the Nares Strait, but has receded dramatically in recent years.

Walruses (Odobenus rosmarus) are spotted on a patch of broken sea-ice as seen from Arctic Sunrise.

Large tabular icebergs calved into Kane Basin in northern Greenland by the Humboldt glacier, the widest glacier in the northern hemisphere.

A view from the Greenpeace ship MY Arctic Sunrise as she leaves her temporary base at Hall Basin opposite the Petermann glacier, due to drifting sea ice, to find her new location further south.

A huge iceberg rising 36 metres from the waters of Kane Basin. It is likely that this unusual feature started life as an englacial channel within the Humboldt glacier that it has calved from.

Glaciologist Dr Richard Bates, of the Scottish Oceans Institute at the University of St. Andrews, takes ‘casts’ of temperature pressure current and salinity on the Petermann glacier.

A polar bear photographed from the deck of the Arctic Sunrise, in drifting and unconsolidated sea ice in Kane Basin, off Cape Clay.