Explaining, Connecting and Communicating the Nordic Seas Overturning from Space

Due to its central importance to Earth’s climate, there is a pressing need for a simple system for continuous monitoring of the Nordic Seas overturning circulation that tells us about the total strength of the inflowing warm waters into the Nordic Seas and the Arctic and the outflowing cold dense waters into the North Atlantic Ocean.

The long-term stability of this circulation is indicative of a healthy Atlantic Meridional Overturning Circulation (AMOC), popularly known as the “Gulf Stream”, which is key in shaping our climate and its variability, both over ocean and land.

As such, it is considered one of Earth’s climate tipping points: changes in the AMOC can set in motion a global cascade of teleconnections that can irreversibly alter weather and climate patterns and the life cycles of greenhouse gases.

Yet, our understanding of the AMOC, especially its key component in the Nordic Seas (hereafter “Nordic Seas MOC”), is limited and incomplete.

ECO2NORSE is a timely effort that capitalizes on recent AMOC knowledge from satellite observations to generate a Nordic Seas MOC estimate in order to provide a fresh understanding of its dynamics, variability, connectivity, and change during the satellite era.

ECO2NORSE is expected to generate and communicate critical knowledge, both of immense scientific and societal relevance, on how this circulation may be altered under future warming and what risks our oceans and climate may face.To achieve this goal requires an estimate of the Nordic Seas MOC, i.e., including the total transport of the northward warm-water inflow and southward cold-water overflow.

This information has hitherto been incomplete since not all branches have been monitored continuously during the satellite era.

To reconstruct these unknowns in this dynamical system from satellite observations is thus critical and at the heart of ECO2NORSE.

With this reconstruction, we will develop a more complete understanding of how the Nordic Seas MOC has changed over time during the satellite era, close knowledge gaps on its forcing mechanisms across time scales, and assess the nature of the coupling to upstream MOC changes, both in terms of connectivity and stability.The ultimate goal of ECO2NORSE is, apart from developing a simple monitoring system of the Nordic Seas MOC that can serve the community as a whole, to advance our interpretation of available AMOC estimates across the entire Atlantic, AMOC paleo proxies, and constraining past AMOC variations, ultimately leading to increased confidence statements in IPCC assessment reports.

This information, which will be communicated to the public and used to educate young students, is critical for our society as well as for decision-making about climate change impacts, adaptation, and mitigation.