Advances in understanding and parameterization of small-scale physical processes in the marine Arctic climate system: a review

Abstract

Abstract. The Arctic climate system includes numerous highly interactive small-scale physical processes in the atmosphere, sea ice, and ocean. During and since the International Polar Year 2007-2009, significant advances have been made in understanding these processes. Here, these recent advances are reviewed, synthesized, and discussed. In atmospheric physics, the primary advances have been in cloud physics, radiative transfer, mesoscale cyclones, coastal, and fjordic processes as well as in boundary layer processes and surface fluxes. In sea ice and its snow cover, advances have been made in understanding of the surface albedo and its relationships with snow properties, the internal structure of sea ice, the heat and salt transfer in ice, the formation of superimposed ice and snow ice, and the small-scale dynamics of sea ice. For the ocean, significant advances have been related to exchange processes at the ice-ocean interface, diapycnal mixing, double-diffusive convection, tidal currents and diurnal resonance. Despite this recent progress, some of these small-scale physical processes are still not sufficiently understood: these include wave-turbulence interactions in the atmosphere and ocean, the exchange of heat and salt at the ice-ocean interface, and the mechanical weakening of sea ice. Many other processes are reasonably well understood as stand-alone processes but the challenge is to understand their interactions with and impacts and feedbacks on other processes. Uncertainty in the parameterization of small-scale processes continues to be among the greatest challenges facing climate modelling, particularly in high latitudes. Further improvements in parameterization require new year-round field campaigns on the Arctic sea ice, closely combined with satellite remote sensing studies and numerical model experiments.

Pan-Eurasian Experiment (PEEX): towards a holistic understanding of the feedbacks and interactions in the land–atmosphere–ocean–society continuum in the northern Eurasian region

“…To be able to predict the future evolution of the sea ice cover, the first priority is to better understand the reasons, including the role of black carbon (see Bond et al, 2013), behind the past and ongoing sea ice evolution. Several processes have contributed to the decline of Arctic sea ice cover, but the role of these processes needs better quantification (Smedsrud et al, 2013;Vihma et al, 2014). Further studies are needed on the impacts of changes in cloud cover and radiative forcing (Kay et al, 2008), atmospheric heat transport (Kapsch et al, 2013) and oceanic heat transport (Döscher et al, 2014).…”

Recent advances in understanding the Arctic climate system state and change from a sea ice perspective: a review

“…Albedo at the surface of sea ice, or snow on top of sea ice, is the crucial property limiting the effect of short-wave radiation on the ice (for recent advances in physics and parameterizations, see Vihma et al, 2014). Values for albedo at the ice or snow surface have long been derived from local direct observations.…”

“…Major contributions were made from the Inter-national Polar Year (IPY) and connected programs such as DAMOCLES and SEARCH. DAMOCLES studies on sea ice remote sensing are summarized in Heygster et al (2012) and those on recent advance related to small-scale physical processes by Vihma et al (2014).…”

“…We focus on the large-scale state and changes in the Arctic climate system, affecting and interacting with the sea ice cover. (Recent advances in understanding smallscale physical processes were addressed in another DAMO-CLES synthesis paper by Vihma et al (2014).) For a discussion of the consequences and impacts of declining sea ice cover, see e.g.…”

Grand Challenges in Cryospheric Sciences: Toward Better Predictability of Glaciers, Snow and Sea Ice

“…A review of recent advances in parameterizing sea iceatmosphere processes is presented by Vihma et al (2014). Carmack et al (2015) include a review of sea ice-ocean processes.…”