Research database

Project information
Arctic Ocean, Oceanography, Sea-ice, Biogeochemistry, Tracer, Pacific, Atlantic, Inflow, Outflow #trimodalFRAM
Project title
TRIMODAL: Using Tracers, Atmospheric Indices and Model Output to explain changes in the Arctic Ocean Inflow and Outflow through Fram Strait
Project leader
Paul Dodd, Norwegian Polar Institute,
Geographical localization of the research project in decimal degrees (max 5 per project, ex. 70,662°N and 23,707°E)
Fram Strait: N 78° 50°, W 015° 00’ to N 78° 50’, E 010° 00’

Laura de Steur, Norwegian Polar Institute

Justin Gwynn, Norwegian Radiation Protection Authority*

Tore Hattermann, Akvaplan-niva

Mats Granskog, Norwegian Polar Institute

Katrin Bluhm, Akvaplan-niva*

Agneta Fransson, Norwegian Polar Institute

Melissa Chierici, Institute of Marine Research*

Michael Karcher, Ocean Atmosphere Systems*

* = “responsible administrative person for each institute”

Arctic Ocean
Funding Source

1 000 000 NOK from the Fram Centre Arctic Ocean Flagship, plus 757 000 NOK in-kind contributions from NPI, IMR and the OA-State project in the form of ship time and laboratory and data analysis time.

Summary of Results

  • 31 sections of historical N:P measurements (1984-2015) across Fram Strait were collated and passed QC checks.

  • Derived Pacific water fractions in Fram Strait reveal distinct high and low Pacific water regimes lasting several years.

  • Comparison of observations in Fram Strait and in remote locations suggests that a strong, coherent pulse of Pacific water travelled past the North Pole, though Fram Strait and on to Denmark Strait in 2011/2012

  • Early results of NAOSIM model experiments including a Pacific water tracer compare favourably with observations of Pacific water in Fram Strait and reval new information about the pathways of Pacific water in the Arctic Ocean. The results suggest NOASIM experiments will improve understanding of the upstream drivers of changes observed in Fram Strait and will be continued.



Tables 1-3 below list the progress made with each of the tasks described in the 2016 proposal.


Table 1: Progress summary for WP1


table2Table 2: Progress summary for WP2


table3Table 3: Progress summary for WP3




Master and PhD-students involved in the project


In 2016 TRIMODAL paid travels costs so that Phillip Anhaus (Masters Student, UiB), Silje Smith-Johnsen (PhD student, UiB) and Antonia Doncilla (PhD Student, University of Edinburgh, UK) could join NPI’s 2016 Fram Strait cruise to assist with tracer sampling. These students received one-to-one hands-on training in setup and use of standard oceanographic instruments (ADCP, CTD, salinometer) and initial data processing.


Torgeir Blæsterdalen was employed at a research assistant for 5.5 months within TRIMODAL in August 2016 immediately after finishing his master thesis at UiT and has received training in the use of biogeochemical tracer techniques.


For the Management

TRIMODAL will identify important processes affecting the Arctic Ocean circulation and deliver essential new knowledge that will improve ocean and sea-ice predictions. In 2016 the project combined new and existing tracer measurements from Fram Strait to provide a continuous 31-year time series that is now being used to identify processes driving variations in currents flowing in and out of the Arctic Ocean in conjunction with early results from model simulations. In 2017 & 2018 the long time series of observations will be compared with results from two different numerical models to investigate how the changing atmosphere, declining sea-ice cover and the internal response of the Arctic Ocean influence circulation.


Published Results/Planned Publications

The following publications are planned for the 3-year project period:


(1) Composition and Quantity of Freshwater Exported from the Arctic Ocean Though Fram Strait (1982-present). Submission to JGR-Oceans Q4 2016. (In preparation, the paper will focus on changes in Pacific freshwater fractions and factors affecting the path of Pacific water through the Arctic Ocean).

(2) The (iodine) Tracer Properties of Inflowing, Outflowing and Re-circulating Atlantic Water in Fram Strait and Residence Times in the Arctic Ocean. For submission to Marine Chemistry Q4 2017. (Work to begin 2017).

(3) Comparison of Modeled Transports of Freshwater Fractions and Tracer-Derived Observations of Freshwater Fractions under various atmospheric conditions. For submission Q4 2018 (Work to begin 2018).

(4) Atmospheric forcing of freshwater transport in the Arctic Ocean evaluated using observations and model simulations of the Fram Strait Freshwater Outflow. For submission to JGR-Oceans Q4 2018. (Work to begin 2018).

Communicated Results

Updates from TRIMODAL’s 2016 field campaign were disseminated through social media channels by the Oceans and Sea Ice group at the Norwegian Polar Institute on Instagram, Twitter and Facebook (@oceanseaicenpi). A hashtag #trimodalFRAM has been used to keep track of posts related to the project. Subscriptions to Hootsuite Pro and Iconosquare Plus social media content management systems allowed us to track available analytics for all social media channels, such as the geographic spread and age of the audience. Evaluation of performance of social media posts published on different days and time of the day helps to optimize social media posts and reach out larger audience. As a test, a Facebook promotion campaign was run for 2 weeks in order to evaluate its effectiveness for audience growth. Within the first three days of the campaign, the number of page likes doubled (> 1400 people), thus, enlarging the audience of the project. Outcomes of the test of Facebook page promotion will be used for a planned manuscript, highlighting experience of our group in science communication and outreach via social media. Tentative submission of this manuscript is in December 2016

Figure 1: Example of a #trimodalFRAM social media post


Interdisciplinary Cooperation

TRIMODAL combines two different disciplines: long term observations and numerical model simulations. 25% of the partners identify themselves as numerical modellers, 75% as observationalists – the project aims to use techniques from both disciplines to investigate changes in the Arctic Ocean Inflow and Outflow.

Budget in accordance to results

Funding in 2016 was sufficient to carry out the planned sample collection and laboratory analysis, perform some basic NAOSIM model experiments and to employ a research assistant for 5.5 months from August to December.

In the 2016 proposal, we requested 9 months of research assistant time. If funding allows, we would like to re-employ the research assistant for 2 months in 2017 to ensure that observational data analysis can keep pace with the original project plan.

Given the promising early results of NAOSIM modelling experiments used to trace Pacific Water, we would like to conduct additional NAOSIM model experiments to trace river water and sea ice meltwater. These additional experiments will improve our understanding of the distinct dynamics of these two important components of freshwater export in Fram Strait and support the interpretation of observed data.

Could results from the project be subject for any commercial utilization

Progress in 2016 broadly followed the project plan - early results are very encouraging!