Arctic freshwater export: Status, mechanisms, and prospects

Abstract

Large freshwater anomalies clearly exist in the Arctic Ocean. For example, liquid freshwater has accumulated in the Beaufort Gyre in the decade of the 2000s compared to 1980-2000, with an extra ≈ 5000 km 3-about 25%-being stored. The sources of freshwater to the Arctic from precipitation and runoff have increased between these periods (most of the evidence comes from models).

Volume and temperature transports through the main Arctic Gateways: A comparative study between an ocean reanalysis and mooring-derived data

“…The four major Arctic gateways (Davis, Fram and Bering Strait and the Barents Sea Opening) have been monitored by several research groups for many years (Dickson et al, 2007;Haine et al, 2015). Integrating the individual mooring arrays across the 10 Arctic boundary, Tsubouchi et al (2017b) The main data source are 138 moored instruments spread across the Arctic gateways.…”

“…For computation of the observation-based data, the initial surface freshwater flux is set to 0.18 Sv, based on climatological 'P minus E' and R values compiled from a few different sources (Tsubouchi et al, 2012). We would like to point out that the observation-based volume transport estimate of -0.15 ± 0.06 Sv together with the volume transport by sea 15 ice (-0.07 Sv, derived from -2080 km³/yr (Haine et al, 2015) using 1Sv = 31,536 km³/yr) nicely balances the 0.20 ± 0.08 Sv surface freshwater flux obtained from the inverse-model calculations, as discussed by Tsubouchi et al (2017b). This is also in excellent agreement with the updated surface freshwater flux estimate (0.203 ± 0.016 Sv or 6400 km³/yr, Carmack et al, 2016).…”

Quality assessment of the TOPAZ4 reanalysis in the Arctic over the period 1991–2013

“…The recent warming of the Arctic and the change of its water cycle has been linked to the following manifestations: a significant reduction and thinning of the sea ice cover (Johannessen et al, 2004;Shimada et al, 2006;Rothrock et al, 2008;Kwok and Rothrock, 2009), more freshwater in the Arctic in the 2000s (Haine et al, 2015) and more mobility and faster deformations of the Arctic sea ice (Rampal et al, 2009;Spreen et al, 2011). The interpretation of such changes is severely hampered by the sparseness of the concerned observations, which should not be improved dramatically in the near future.…”

Towards an assessment of riverine dissolved organic carbon in surface waters of the western Arctic Ocean based on remote sensing and biogeochemical modeling

“…The Arctic Ocean (AO) receives ∼ 10 % of the global freshwater discharge (Opsahl et al, 1999 and references therein), of which the larger part (∼ 54-64 %) originates from six main pan-Arctic rivers (Haine et al, 2015;Holmes et al, 2012;Aagaard and Carmack, 1989). Over the past 30 years, the Arctic freshwater cycle intensified as reflected by changes in snow cover (Bring et al, 2016), evapotranspiration from terrestrial vegetation (Bring et al, 2016), and precipitation (Vihma et al, 2016).…”