Overview of the Arctic Sea state and boundary layer physics program
2018-04-16,
Thomson, Jim,
Ackley, Stephen,
Girard-Ardhuin, Fanny,
Ardhuin, Fabrice,
Babanin, Alexander,
Boutin, Guillaume,
Brozena, John,
Cheng, Sukun,
Collins, Clarence,
Doble, Martin,
Fairall, Christopher W.,
Guest, Peter,
Gebhardt, Claus,
Gemmrich, Johannes,
Graber, Hans C.,
Holt, Benjamin,
Lehner, Susanne,
Lund, Björn,
Meylan, Michael,
Maksym, Ted,
Montiel, Fabien,
Perrie, Will,
Persson, Ola,
Rainville, Luc,
Rogers, W. Erick,
Shen, Hui,
Shen, Hayley,
Squire, Vernon,
Stammerjohn, Sharon E.,
Stopa, Justin,
Smith, Madison M.,
Sutherland, Peter,
Wadhams, Peter
A large collaborative program has studied the coupled air‐ice‐ocean‐wave processes occurring in the Arctic during the autumn ice advance. The program included a field campaign in the western Arctic during the autumn of 2015, with in situ data collection and both aerial and satellite remote sensing. Many of the analyses have focused on using and improving forecast models. Summarizing and synthesizing the results from a series of separate papers, the overall view is of an Arctic shifting to a more seasonal system. The dramatic increase in open water extent and duration in the autumn means that large surface waves and significant surface heat fluxes are now common. When refreezing finally does occur, it is a highly variable process in space and time. Wind and wave events drive episodic advances and retreats of the ice edge, with associated variations in sea ice formation types (e.g., pancakes, nilas). This variability becomes imprinted on the winter ice cover, which in turn affects the melt season the following year.
Emerging trends in the sea state of the Beaufort and Chukchi seas
2016-07-06,
Thomson, James M.,
Fan, Yalin,
Stammerjohn, Sharon E.,
Stopa, Justin,
Rogers, W. Erick,
Girard-Ardhuin, Fanny,
Ardhuin, Fabrice,
Shen, Hayley,
Perrie, Will,
Shen, Hui,
Ackley, Stephen,
Babanin, Alexander,
Liu, Qingxiang,
Guest, Peter,
Maksym, Ted,
Wadhams, Peter,
Fairall, Christopher W.,
Persson, Ola,
Doble, Martin J.,
Graber, Hans C.,
Lund, Bjoern,
Squire, Vernon,
Gemmrich, Johannes,
Lehner, Susanne,
Holt, Benjamin,
Meylan, Michael,
Brozena, John,
Bidlot, Jean-Raymond
The sea state of the Beaufort and Chukchi seas is controlled by the wind forcing and the amount of ice-free water available to generate surface waves. Clear trends in the annual duration of the open water season and in the extent of the seasonal sea ice minimum suggest that the sea state should be increasing, independent of changes in the wind forcing. Wave model hindcasts from four selected years spanning recent conditions are consistent with this expectation. In particular, larger waves are more common in years with less summer sea ice and/or a longer open water season, and peak wave periods are generally longer. The increase in wave energy may affect both the coastal zones and the remaining summer ice pack, as well as delay the autumn ice-edge advance. However, trends in the amount of wave energy impinging on the ice-edge are inconclusive, and the associated processes, especially in the autumn period of new ice formation, have yet to be well-described by in situ observations. There is an implicit trend and evidence for increasing wave energy along the coast of northern Alaska, and this coastal signal is corroborated by satellite altimeter estimates of wave energy.