Climate change fosters competing effects of dynamics and thermodynamics in seasonal predictability of Arctic sea ice

Autor(en)
Igor V. Polyakov, Michael Mayer, Steffen Tietsche, Alexey Yu. Karpechko
Abstrakt

The fast decline of Arctic sea ice necessitates a stronger focus on understanding the Arctic sea ice predictability and developing advanced forecast methods for all seasons and for pan-Arctic and regional scales. In this study, the operational forecasting system combining an advanced eddy-permitting ocean-sea ice ensemble reanalysis ORAS5 and state-of-the-art seasonal model-based forecasting system SEAS5 is used to investigate effects of sea ice dynamics and thermodynamics on seasonal (growth-to-melt) Arctic sea ice predictability in 1993-2020.We demonstrate that thermodynamics (growth/melt) dominates the seasonal evolution of mean sea ice thickness at pan-Arctic and regional scales. The thermodynamics also dominates the seasonal predictability of sea ice thickness at pan-Arctic scale; however, at regional scales, the predictability is dominated by dynamics (advection), although the contribution from ice growth/melt remains perceptible. We show competing influences of sea ice dynamics and thermodynamics on the temporal change of ice thickness predictability from 1993-2006 to 2007-20. Over these decades, there was increasing predictability due to growth/melt, attributed to increased winter ocean heat flux in both Eurasian and Amerasian basins, and decreasing predictability due to advection. Our results demonstrate an increasing impact of advection on seasonal sea ice predictability as the region of interest becomes smaller, implying that correct modeling of sea ice drift is crucial for developing reliable regional sea ice predictions. This study delivers important information about sea ice predictability in the "new Arctic"conditions. It increases awareness regarding sea ice state and implementation of sea ice forecasts for various scientific and practical needs that depend on accurate seasonal sea ice forecasts.

Organisation(en)
Institut für Meteorologie und Geophysik
Externe Organisation(en)
University of Alaska Fairbanks, University of Helsinki, European Centre for Medium-Range Weather Forecasts (ECMWF)
Journal
Journal of Climate
Band
35
Seiten
2849-2865
Anzahl der Seiten
17
ISSN
0894-8755
DOI
https://doi.org/10.1175/JCLI-D-21-0463.1
Publikationsdatum
05-2022
Peer-reviewed
Ja
ÖFOS 2012
105204 Klimatologie, 105206 Meteorologie
Schlagwörter
ASJC Scopus Sachgebiete
Atmospheric Science
Sustainable Development Goals
SDG 13 – Maßnahmen zum Klimaschutz
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/climate-change-fosters-competing-effects-of-dynamics-and-thermodynamics-in-seasonal-predictability-of-arctic-sea-ice(7db76fc2-e2eb-4b48-bbf9-2b835f844988).html