Toward Quantifying the Increasing Role of Oceanic Heat in Sea Ice Loss in the New Arctic

Abstract

Small changes in the ways that the ocean transports heat to the overlying ice cover could have a substantial effect on future changes in Arctic ice cover.

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

“…Representing the variability from these competing processes is important for correctly modeling climate sensitivity (Notz, 2015). Carmack et al (2015) document the terms that have most uncertainty in the sea-ice surface energy budget. The atmospheric flux components introduce an order of 10 Wm −2 uncertainty, which is more than enough to explain recent ice loss.…”

“…Carmack et al (2015) include a review of sea ice-ocean processes. Climate model sensitivity is related to the representation of sea-ice processes, and models present wide variability in their representation of the sensitivity of sea ice to greenhouse gas forcing (Stroeve and Notz, 2015).…”

“…Decreasing sea-ice mass implicit from the observational evidence has been associated with: changes in ice drift (Rigor and Wallace, 2004;Nghiem et al, 2007) and increased divergence of the pack (Hutchings and Perovich, 2015), both of which precondition the pack for enhanced melt; changes in cloudiness (Kay et al, 2008), which affects both shortwave and longwave radiation balance; and increasing Pacific summer water inflow to the Chukchi Sea Woodgate et al, 2010Woodgate et al, , 2012. Also, an increasing Atlantic water inflow to the eastern Arctic (Polyakov et al, 2012) is another heat source, that may reach the ice through various mixing mechanisms (Carmack et al, 2015). Variability in Atlantic water in the Arctic may be related to the Atlantic Multidecadal Oscillation and a similar period of oscillation in the sea-ice pack (Miles et al, 2014).…”

“…This heat also becomes entrained into a near surface layer of warm water (Jackson et al, 2010) which is mixed upwards during storms (Jackson et al, 2012;Zhang et al, 2013), melting ice or delaying ice freeze-up. Other oceanic dynamic processes can bring heat upward from depth transported into the Arctic from the Atlantic and Pacific (Carmack et al, 2015). Processes that provide the majority of heat flux to the ice are micro-and mesoscale.…”

Method to characterize directional changes in Arctic sea ice drift and associated deformation due to synoptic atmospheric variations using Lagrangian dispersion statistics

“…Here, the largescale ice-covered oceanic Beaufort Gyre circulation pattern is predominantly anticyclonic (clockwise) with reversals to cyclonic (counter clockwise) circulation throughout the annual cycle in response to changing surface wind patterns and oceanic responses to coastal boundaries (LeDrew et al, 1991;Preller and Posey, 1989;Lukovich et al, 2011;Proshutinsky et al, 2015). When circulation patterns change, the ice cover changes abruptly, which impacts navigation channels as a result of ice-ice and ice-coastline momentum and energy flux exchanges (e.g., The Polar Group, 1980;Hwang, 2005;McPhee, 2012), and air-sea heat exchanges increase (e.g., Carmack et al, 2015), with newly opened leads venting large amounts of moisture into the atmosphere as a strong mass exchange process (Bourassa et al, 2013). Understanding how these changes develop and relate to the orientation of a coastline is essential when diagnosing response patterns.…”