North Atlantic Heat Transport Convergence Derived from a Regional Energy Budget Using Different Ocean Heat Content...

Area of Science:

• Oceanography
• Climate Science
• Earth System Science

Background:

• Accurate estimation of ocean heat transport is crucial for understanding global climate dynamics.
• The North Atlantic plays a significant role in global heat distribution.
• Previous methods for estimating ocean heat transport convergence had limitations.

Purpose of the Study:

• To estimate ocean heat transport convergence in the North Atlantic using an oceanic energy budget approach.
• To validate this indirect estimation against in-situ measurements from RAPID and OSNAP.
• To assess the robustness of the method across different ocean heat content tendency derivations.

Main Methods:

• Utilized satellite altimetry and space gravimetry to derive ocean heat content tendency.
• Inferred net surface energy fluxes from atmospheric energy transport and reanalysis data.
• Integrated indirect estimates between the RAPID (26.5°N) and OSNAP (53°-60°N) sections for validation.

Main Results:

• The North Atlantic ocean energy budget between RAPID and OSNAP sections was closed to within ±0.25 PW.
• Mean oceanic heat transport convergence was estimated at 0.58 ±0.25 PW, aligning well with observed transports.
• Interannual variability showed reasonable agreement with in-situ data (correlation of 0.54 for annual, 0.67 for biannual time series).

Conclusions:

• The oceanic energy budget method provides a reliable estimate of North Atlantic ocean heat transport convergence.
• The findings are robust across various methods for estimating ocean heat content tendency.
• This study validates a key component of the ocean's role in climate regulation.