Objectives

In recent decades we have seen major changes in Arctic Ocean circulation, salinity, and temperature and associated declines in sea ice coverage and thickness. There is evidence of connections of these changes with climate indices, and the changes arguably affect climate by altering the radiative heat balance at high latitudes, impacting the strength of the global overturning circulation, and influencing the interaction between the ocean and Greenland ice sheet. There are also indications that Arctic sea ice and atmospheric circulation can play an important role in extended range predictability of extreme weather events in mid-latitudes. In spite of its importance, Arctic Ocean observations are limited. Several major in situ observing programs that existed in the 2000s have ended, and today sustained oceanographic observations outside the Canada Basin have almost ceased to exist. This workshop will aim to assess our understanding of the Arctic Ocean circulation and discuss observing system requirements needed to confirm and extend that understanding.

More specifically, the workshop will explore changes in Arctic Ocean and sub-Arctic seas circulation related to global change and the observing system required to track those changes in the future. The observing system design effort will be cognizant of the practical, geopolitical, and operational constraints of Arctic Ocean observing, but will incorporate modern objective experimental design and data assimilation using numerical models as fundamental guiding principles. Its work will contribute to evaluations of model simulations and observational analyses to assess opportunities for model improvements.

The US CLIVAR Observing, Modeling, and Understanding the Circulation of the Arctic Ocean and Sub-Arctic Seas Workshop will include presentations addressing:

A. The state of knowledge of Arctic Ocean and sub-Arctic seas circulation with an eye toward identifying critical gaps in observations of modes of variability
B. The observing system needs and data assimilation approach to track those modes of variability
C. The practical, institutional, technical, and geopolitical challenges of increasing the coverage of Arctic Ocean observations that are required by A) and B)

Target Participants

Attendance is open to all, with participation sought from the following communities:

• Observationalists (in situ and remote sensing) who are focused on the circulation of the Arctic Ocean and sub-Arctic seas
• Data assimilation experts and modelers with an interest in estimating and predicting circulation in the Arctic Ocean and sub-Arctic seas
• Investigators and early career scientists with interest in understanding the mechanisms driving variability and change in Arctic Ocean and sub-Arctic seas circulations and relation to climate indices

Registration is on a first come, first-served basis until capacity is reached. The organizing committee anticipates 100-120 participants at the workshop. Abstracts are not a requirement for participation. Limited travel support is available for early career scientists (within five years of PhD), with priority support for US researchers. A short application form will be provided during registration. Abstracts for poster and a limited number of oral presentations will be due in early-mid June, with decisions and notifications made by July. General registration for the workshop will close in September 2020.

Location/Date

Seattle, Washington. July 12-15, 2021.

Workshop Format

The 3.5-day meeting will consist of plenary sessions comprised of invited overview summary talks, breakout sessions, and discussion covering three topics: a) the state of knowledge of Arctic Ocean and sub-Arctic seas circulation, b) the observing system and data assimilation needs to track circulation variability, and c) the practical, institutional, technical, and geopolitical challenges of increasing the observational coverage of Arctic Ocean.

Outcomes

Deliverables include:

• Community building across the physical ocean and ice communities studying the Arctic Ocean and sub-Arctic seas
• Consensus state of understanding of the changes in the circulation of Arctic Ocean and sub-Arctic seas and their relation to climate indices
• Identification of needs for sustained ocean observations to measure variability and change in Arctic Ocean circulation and approaches for supporting them
• Strategy for synthesis of in-situ and satellite measurements with assimilative modeling to estimate the state and evolution of circulation within the Arctic Ocean and sub-Arctic seas

The organizing committee will share results with the broader community through a workshop report.

Scientific Organizing Committee

Jamie Morison, University of Washington (chair)
Alison Macdonald, Woods Hole Oceanographic Institution
Mary Louise Timmermans, Yale University
Sergey Frolov, NOAA ESRL
Patrick Heimbach, University of Texas at Austin

Program Organizing Committee

Mike Patterson (US CLIVAR)
Jennie Zhu (US CLIVAR)

Workshop Sponsors