Changes in glacier extent on north Novaya Zemlya in the twentieth century

Abstract

Glacier retreat on north Novaya Zemlya for the past century was documented by registering glacier terminus positions from expedition and topographic maps and remotely sensed images. Recession of tidewater calving glaciers on north Novaya Zemlya in the first half of the twentieth century was relatively rapid (>300 m yr-1), consistent with post-‘Little Ice Age’ warming documented by a 122-year instrumental record from Malye Karmakuly. The glaciers completed 75 to 100% of the net twentieth-century retreat by 1952. Between 1964 and 1993 half of the studied glaciers were stable; the remainder retreated modest distances of <2.5 km. This stability coincides with decreasing average temperatures, especially during the winter, which is counter to model prediction. There is a statistically significant covariance of unfiltered winter and summer temperatures from Novaya Zemlya and a smoothed 88-year record of SSTs in the southern Barents Sea (r>0.75). Elevated SST in the Barents Sea appear to reflect increased advection of warm North Atlantic water associated with a positive North Atlantic Oscillation index (NAO). Winter temperatures are periodically correlated with the NAO (r = 0.75 to 0.9) reflecting repeated penetration of Atlantic cyclones into the Arctic. During the twentieth century, an overall positive glacier mass balance trend at Novaya Zemlya is associated with a positive phase of the NAO, elevated southern Barents Sea SST, and a concomitant increase of winter precipitation. Strong NAOs enhance winter precipitation and (3–5 yr delayed) summer temperatures on Novaya Zemlya and have a variable effect on Novaya Zemlya glaciers.

Exceptional retreat of Novaya Zemlya's marine-terminating outlet glaciers between 2000 and 2013

“…Dowdeswell et al, 2008;Moon and Joughin, 2008;Pritchard et al, 2009;Sole et al, 2008) and was linked to changes in sea ice concentrations (Carr et al, 2014). However, the pattern of frontal-position changes on NVZ prior to 1992 is uncertain, and previous results indicate different trends, dependant on the study period: some studies suggest glaciers were comparatively stable or retreating slowly between 1964 and 1993 (Zeeberg and Forman, 2001), whilst others indicate large reductions in both the volume (Kotlyakov et al, 2010) and the length of the ice coast (Sharov, 2005) from ∼ 1950 to 2000, and longer-term retreat (Chizov et al, 1968;Koryakin, 2013;Shumsky, 1949). Consequently, it is difficult to contextualize the observed period of rapid retreat from ∼ 2000 until 2010 (Carr et al, 2014) and to determine if it was exceptional or part of an ongoing trend.…”

“…Furthermore, there are substantial differences in climatic and oceanic conditions on the two coasts (Figs. 4 and 7) (Pfirman et al, 1994;Politova et al, 2012;Przybylak and Wyszyński, 2016;Zeeberg and Forman, 2001), so we would expect to see significant differences in outlet glacier retreat rates. This indicates that longer-term glacier retreat rates on NVZ may relate to much broader, regional-scale climatic change, which is supported by the widespread recession of glaciers across the Arctic during the past 2 decades (e.g.…”

“…contrast, the Kara Sea coast is isolated from North Atlantic weather systems, by the topographic barrier of NVZ (Pavlov and Pfirman, 1995), and is subject to cold, Arctic-derived water, along with much higher sea ice concentrations (Zeeberg and Forman, 2001). We therefore aim to investigate whether these differing climatic and oceanic conditions lead to major differences in glacier retreat between the two coasts.…”

“…Specifically, we assessed the impact of coast (Barents Sea versus Kara Sea on the northern ice mass), ice mass (northern island ice cap, Sub 1, or Sub 2), terminus type (marine-, lake-, and land-terminating), and latitude (Table 1). The two coasts of Novaya Zemlya are characterized by very different climatic and oceanic conditions: the Barents Sea coast is influenced by water from the North Atlantic (Loeng, 1991;Pfirman et al, 1994;Politova et al, 2012) and subject to Atlantic cyclonic systems (Zeeberg and Forman, 2001), which results in warmer air and ocean temperatures as well as higher precipitation (Przybylak and Wyszyński, 2016;Zeeberg and Forman, 2001). In Moholdt and available via GLIMS database).…”

Observations: Cryosphere

“…• Zeeberg and Forman (2001) analyzed twentieth century changes in glaciers on north Novaya Zemlya-a Russian island located between the Barents and Kara Seas in the Arctic Ocean. Here, an accelerated post-Little Ice Age glacial retreat occurred in the first and second decades of the twentieth century.…”