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Widespread global disparities between modelled and observed mid-depth ocean currents.
Fenzhen Su1,2,3,4, Rong Fan5,6, Fengqin Yan5,6
1State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China. sufz@lreis.ac.cn.
Nature Communications
|April 12, 2023
Summary
Mid-depth ocean circulation models are inaccurate, with only 3.8% of regions well-represented. This impacts climate change predictions, necessitating improved ocean current observation and modeling for accurate forecasting.
Area of Science:
- Oceanography
- Climate Science
- Geophysics
Background:
- Mid-depth ocean circulation is crucial for long-term global climate regulation.
- Current ocean circulation models lack sufficient data and long-term implications for climate change assessments.
Purpose of the Study:
- To assess the accuracy of current mid-depth ocean circulation models.
- To identify regions with significant underestimations in modeled current velocity.
- To propose improvements for ocean current forecasting and observation.
Main Methods:
- Utilized 842,421 Argo float observations from 2001-2020.
- Employed Lagrangian simulations to analyze ocean current data.
- Compared model predictions against observational data.
Main Results:
- Only 3.8% of mid-depth ocean regions, including parts of the equatorial Pacific and Antarctic Circumpolar Current, are accurately modeled.
- Significant underestimations in mean current velocity were found in many regions.
- Ocean circulation knowledge is better in low latitudes but poor in high latitudes.
Conclusions:
- Global ocean circulation models are substantially compromised by inaccuracies.
- These inaccuracies have significant implications for predicting currents, temperature, carbon sequestration, and sea-level rise.
- Enhanced observations and improved model stochasticity are recommended for better climate predictions.
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