Relative sea-level changes along the Northern Sea Route: from patterns and rates to drivers and mechanisms
The rapidly changing climate, rising temperatures and declining Arctic Sea ice have the potential to open the Northern Sea Route (NSR). Sailing routes between Europe and East Asian ports such as Singapore through the Arctic Ocean along the NSR are as much as ~40% shorter than the established routes around the Cape of Good Hope and are ~25% shorter than the routes via Suez Canal. To design appropriate coastal infrastructure and minimize potential risk, information on future relative sea-level (RSL) and bathymetry changes in the Arctic are required. RSL projection relies on an accurate understanding of the mechanisms driving its complex spatio-temporal evolution, which must be founded on an understanding of their history. Future RSL changes along the NSR in the Eurasian Arctic are controlled by the increase in ocean mass and volume and vertical land motion from glacial-isostatic adjustment (GIA). GIA is the response of the solid Earth and gravity field to ice mass redistribution during a glacial cycle. However, the robustness of GIA models relies on the accuracy of their input parameters: ice-sheet histories and mantle rheological properties. Geological RSL data provide critical constraints on these input parameters.
There is an urgent need for high-quality geological RSL data from the Russian Arctic because global GIA models such as ICE-6G_C (VM5a) and ICE-7G_NA (VM7) have not been validated with the post-Last Glacial Maximum (LGM) datasets (26,000 years ago to present) from this region. Furthermore, the thickness and extent of the Eurasian ice complex, which has a first-order control on patterns of uplift vs. subsidence in this region is poorly understood. Therefore, the ability of the current generation of GIA models to fit geological RSL data – and thus predict future RSL and bathymetric changes for the NSR – remains untested.
In this project, we will update and expand observations of RSL change along the NSR to achieve the following research objectives:
1. Determining the rates, mechanisms and geographic variability of RSL along the NSR from instrumental and proxy data.
2. Refine input parameters of GIA models to develop a comprehensive model for regional vertical land motion for NSR from GIA that can be incorporated into sea-level projections.
3. To produce projections of RSL and bathymetry change in the 21st and 22nd century along the NSR.
- Ministry of Education, Singapore
Nicole Khan, University of Hong Kong
Alisa Baranskaya and Stanislav Ogorodov, Lomonosov Moscow State University, Russia
W.R. Peltier, University of Toronto, Canada
Robert Kopp, Rutgers University, USA