Spatio-temporal change and variability of Barents-Kara sea ice, in the Arctic: Ocean and atmospheric implications

Abstract

The reduction in Arctic sea-ice in recent decades has been a significant indicator of climate change and is related to weather pattern changes across the Arctic regions. In this study, for the period 1979–2018, we addressed the processes controlling the sea-ice cover in the Barents-Kara Sea (BKS). The inter-annual variability of the sea-ice extent (SIE) in BKS was analyzed using passive microwave satellite observations. The ocean-atmospheric forcing variables which including air temperature (AT), sea surface temperature (SST) and outgoing long-wave radiation (OLR) were derived from ERA-Interim reanalysis data. The spatial correlation analysis was performed for the year 2016 and 1998, where sea ice concentration (SIC) in BKS is recorded as a minimum and maximum respectively. The long-term analysis (1979–2018) shows negative trends of the Arctic SIE (−4.7 ± 0.3% decade−1) with the largest decrease in the Barents Sea (−23 ± 2.5% decade−1) and Kara Sea (−7.3 ± 0.9% decade−1). However, the sea-ice decline in the Barents Sea was recorded very high during the winter (−17.6 ± 2.2% decade−1) compared to the Kara Sea (−0.8 ± 0.2% decade−1). Sea-ice cover in the Barents Sea is more likely to recede during the summers −4.1 ± 0.7 x 103 km2yr−1 due to warm inflow of Atlantic waters. Correlation analysis using statistically significant trend values with p-values ≤ 0.01 was performed from 1982 to 2018, the SIC of BKS showing significant negative correlation analyses with SST (−0.75; p-value = 0.01), SAT (−0.84; p-value = 0.00) and OLR (−0.76; p-value = 0.00). In recent years, Atlantic Multi-decadal Oscillation (AMO) index has become positive due to an increase in SST anomalies, while, AMO does not reflect the cooling events in the BKS. During recent Arctic climate change, caused by atmospheric heat transport, the loss of sea-ice at BKS is becoming a major factor. In this study, new perspectives of the complex processes associated with Arctic warming and the declining sea-ice in the BKS region are demonstrated.