Remote subsurface ocean temperature as a predictor of Atlantic hurricane activity

Area of Science:

• Meteorology
• Oceanography
• Climate Science

Background:

• Predicting North Atlantic hurricane activity is crucial for societal safety.
• Ocean temperature, including North Atlantic/tropical averages and upper ocean heat content, is a known significant predictor.
• Tropical cyclone (TC) activity, measured by accumulated cyclone energy (ACE), is influenced by oceanic thermal conditions.

Purpose of the Study:

• To investigate the relationship between the Atlantic Ocean's thermal state and tropical cyclone (TC) activity.
• To assess the predictive skill of subsurface ocean temperatures compared to sea surface temperature (SST) alone.
• To enhance the operational reliability of hurricane activity predictions.

Main Methods:

• Utilized observed tropical cyclone (TC) records from 1980-2015.
• Employed a 1/4° resolution global ocean reanalysis dataset.
• Analyzed the correlation between Atlantic Ocean thermal conditions and accumulated cyclone energy (ACE).

Main Results:

• Eastern Atlantic Ocean temperature influences TC activity through nonlocal effects, specifically by reducing wind shear.
• Subsurface ocean temperature provides additional predictive skill for TC activity beyond SST.
• Lower-than-normal wind shear in the main development region correlates with more active TC seasons.
• Including upper ocean mean temperatures over the eastern Atlantic domain significantly improves TC activity predictions.
• Remote oceanic effects offer potential for ACE prediction up to 3 months in advance.

Conclusions:

• Upper 40-m ocean average temperature enhances predictions of Atlantic hurricane activity, particularly for September.
• Subsurface ocean thermal conditions are critical for improving the accuracy of long-range hurricane forecasts.
• This research represents a significant advancement toward operationally reliable tropical cyclone activity predictions.