Abstract
AbstractThe hydrological cycle is expected to intensify in a warming climate. However, observational evidence of such changes in the Southern Ocean is difficult to obtain due to sparse measurements and a complex superposition of changes in precipitation, sea ice, and glacial meltwater. Here we disentangle these signals using a dataset of salinity and seawater oxygen isotope observations collected in the Indian sector of the Southern Ocean. Our results show that the atmospheric water cycle has intensified in this region between 1993 and 2021, increasing the salinity in subtropical surface waters by 0.06 ± 0.07 g kg−1 per decade, and decreasing the salinity in subpolar surface waters by -0.02 ± 0.01 g kg−1 per decade. The oxygen isotope data allow to discriminate the different freshwater processes showing that in the subpolar region, the freshening is largely driven by the increase in net precipitation (by a factor two) while the decrease in sea ice melt is largely balanced by the contribution of glacial meltwater at these latitudes. These changes extend the growing evidence for an acceleration of the hydrological cycle and a melting cryosphere that can be expected from global warming.
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy,General Biochemistry, Genetics and Molecular Biology,General Chemistry,Multidisciplinary
Reference67 articles.
1. Armour, K. C., Marshall, J., Scott, J. R., Donohoe, A. & Newsom, E. R. Southern ocean warming delayed by circumpolar upwelling and equatorward transport. Nat. Geosci. 9, 549–554 (2016).
2. Meredith, M. et al. Polar regions. chapter 3, ipcc special report on the ocean and cryosphere in a changing climate. (Cambridge University Press, 2019).
3. Purich, A. et al. Tropical pacific sst drivers of recent antarctic sea ice trends. J. Clim. 29, 8931–8948 (2016).
4. Auger, M., Morrow, R., Kestenare, E., Sallée, J.-B. & Cowley, R. Southern ocean in-situ temperature trends over 25 years emerge from interannual variability. Nat. Commun. 12, 1–9 (2021).
5. Haumann, F. A., Gruber, N. & Münnich, M. Sea-ice induced southern ocean subsurface warming and surface cooling in a warming climate. AGU Adv. 1, e2019AV000132 (2020).
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