Ocean response to tropical cyclone in western North Pacific during 2021

Abstract Ocean surface drifters observe sea surface temperature and currents, while Argo floats measure vertical profiles of ocean temperature and salinity. However, the availability of these ocean observing systems near tropical cyclones is often uncertain, as their movement during such events is not well-documented. Atmospheric forecasting models typically rely on operational ocean analysis data, but the availability of in-situ observations in these regions is often unclear, contributing to the uncertainty in boundary conditions for atmospheric models. To address this gap, we conducted an observational study on tropical cyclones in 2021 to quantify the number of ocean surface drifters and Argo floats in proximity to tropical cyclone tracks. Furthermore, we analyzed how sea surface temperature cooling and mixed-layer depth changes are related to tropical cyclone intensity. The results of this study provide valuable insights for improving tropical cyclone intensity forecasting and related research.