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This study investigates the impact of warm core eddies (WCEs) on the ocean response and intensity of tropical cyclones (TCs) in the Northwest Pacific, focusing on three typhoons in 2018: Jebi, Trami, and Kong-rey. The research uses the Hurricane Weather Research and Forecast (HWRF) model coupled with the MPIPOM-TC ocean model. Idealized WCEs are embedded into the ocean model ahead of each TC. The impacts of WCEs are evaluated by comparing simulations with and without their presence. Uncoupled experiments with the fixed sea surface temperature (SST) serve as a reference for TC maximum potential intensity. To quantitatively assess the impact of WCEs on the SST, enthalpy fluxes, and TC intensity, a Maximum WCE Potential Index (MWPI) is introduced. Our findings indicate that for a WCE with a 200 km radius, the potential to reduce SST cooling ranges from 34 to 37%, while the potential to increase enthalpy fluxes varies between 25 and 39%. The influence of WCEs on TC intensity, as measured by minimum pressure, shows a larger variation from 27% to 48%, depending on the oceanic and atmospheric environmental conditions in each storm. Additional experiments reveal the sensitivity of the MWPI to WCE size, with TC Trami showing less sensitivity due to its slower translational speed. This study underscores the significant role of oceanic thermal conditions, particularly WCEs, in modulating TC intensity. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TC), which are among the most destructive natural phenomena on Earth, have significant impacts on the western boundary current (WBC). We quantify the direct impact of TCs on the surface geostrophic velocity of the Kuroshio, the WBC in the western North Pacific, by analyzing satellite‐derived geostrophic current data and using results from theoretical and numerical models. The study reveals that TCs decrease the surface geostrophic velocity by 14 cm s−1 which is 16% of the mean velocity of the Kuroshio (85 cm s−1), with the reduced velocity maintained for a month. The decrease in velocity of the Kuroshio is mainly (87%) due to the effect of TC‐driven upwelling ("Cooling effect"), the effect of ocean heat uptake after the TC ("Warming effect") being minor (13%); these are basically enabled by the strong thermal gradient around the Kuroshio. Plain Language Summary: The tropical cyclone (TC), also known as hurricane or typhoon, has a strong impact on the ocean as well as the land. In this study, we investigate how TCs affect ocean currents, with special focus on the Kuroshio, the western boundary current (WBC) in the North Pacific region. By analyzing satellite‐derived data, and building theoretical and numerical models, we deduce that when a TC hits the Kuroshio, its surface velocity decreases by 16%. This work makes a significant contribution by providing a quantitative understanding of the influence of TCs on the WBC. Further, given that the WBC is the strongest ocean current system on Earth and plays a key role in maintaining global heat balance, this study emphasizes the potential importance of the TC‐induced change on the current for the global distribution of heat energy. Key Points: Tropical cyclones (TC) decrease the surface geostrophic velocity of the Kuroshio by 14 cm s−1 (16% of the mean velocity)"Cooling Effect" of the TC‐driven upwelling explains 87% of the geostrophic velocity decrease immediately after a TC"Warming Effect" of the ocean heat uptake explains 13% of the geostrophic velocity decrease, which is maintained for ∼30 days after a TC [ABSTRACT FROM AUTHOR]

The National Typhoon Center of the Korea Meteorological Administration developed a statistical–dynamical typhoon intensity prediction model for the western North Pacific, the CSTIPS-DAT, using a track-pattern clustering technique. The model led to significant improvements in the prediction of the intensity of tropical cyclones (TCs). However, relatively large errors have been found in a cluster located in the tropical western North Pacific (TWNP), mainly because of the large predictand variance. In this study, a decision-tree algorithm was employed to reduce the predictand variance for TCs in the TWNP. The tree predicts the likelihood of a TC reaching a maximum lifetime intensity greater than 70 knots at its genesis. The developed four rules suggest that the pre-existing ocean thermal structures along the track and the latitude of a TC's position play significant roles in the determination of its intensity. The developed decision-tree classification exhibited 90.0% and 80.5% accuracy in the training and test periods, respectively. These results suggest that intensity prediction with the CSTIPS-DAT can be further improved by developing independent statistical models for TC groups classified by the present algorithm. [ABSTRACT FROM AUTHOR]