It's hard to get Arctic field research to adhere to any kind of plan. Mosaic has just had one bad thing happen after another, from not being able to find a suitable floe back in October, unexpectedly rapid TransPolar Drift, seven weeks lost in a resupply snafu, time and sensors wasted in the Fram, abandoned instruments lost to ice motion, more resupply and repositioning delays and the most scientifically damaging of all, loss of the Polar5 and Polar6 spring and summer overflight campaigns.
https://tinyurl.com/y5dyk83u press release
Had these synergistic transects been flown (for atmospheric measurements, pressure ridge and melt pond lidar and ice thickness) the swath of the Polarstern would have been greatly widened. However the Svalbard airport was shut down to non-Norwegian aircraft until just a few days ago. A fall campaign has been started; no information is available on number and routes of flights.
Arguably, the most important thing the Polarstern has done is set out more buoys along its route over and beyond the north pole. While some types of buoys can be air-dropped, others need to be set into place after drilling and confirmed to be working as designed (ie not going sideways through fractures in pressure ridge as was seen in underwater ROV scenes).
Quite a few buoys are currently active in the Arctic Ocean basin, mainly from non-Mosaic projects. Uniq has located a lot of them and plotted their recent drift paths; those are put onto yesterday's AMSR2_AWI below.
The buoy map can only be produced currently relative to the 0 meridian so the Greenland-down AMSR2_AWI has to be rotated 45º. Only the final frame of Uniq's gif is shown. The trick in producing readable text in the overlay is combining 'darken only' over the ice and 'lighten only' over open water.It's difficult to apportion ice pack edge changes on the Barents side into melt and movement contributions. No question, lateral melt momentum has been going on steadily for months but per GFS nullschool, persistent and consistent winds are blowing the whole ice pack towards Alaska.
The PS has been stably moored to its current floe since Aug 23 (after leaving the pole on the 19th). This floe has drifted north and east (larger lat and lon) since then. Over the last 11 days, the ship has moved 89.5 km for a speed of 0.324 km/hr without any indication of dimensional melt or compaction in its vicinity.
Presumably the ice edge has been moving north at an even faster nominal rate because of contribution of disappearing peripheral melt there. However subtracting two small numbers of pixel displacements is fraught with error.
The Polarstern is just one point. OsiSaf potentially offers speeds of ice passing by all its grid points. Below, I isolated one grid cell close to the ice edge and chained up arrows over 8 days to get displacement there. The data comes with a 3x vector exaggeration. It is shown together with a display of ship GPS on google earth, jagged because Mosaic cuts off 3 dp from what it shares.
Note this melt season will have exceeded
53% BOE for over a month this year (based on pixel counts on a non-equal area projection). The associated loss of planetary refrigeration is discussed quantitatively in K Pistone et al 2019 "Radiative Heating of an Ice-Free Arctic Ocean":
• The complete disappearance of Arctic sea ice would contribute an additional solar radiative heating of 0.71 W/m2 to the planet, equivalent to the radiative forcing from one trillion tons of CO2 emissions
• The added solar heating from complete Arctic sea ice loss would be an order of magnitude larger in the month of May than in the month of September
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