Abstract
AbstractThe radially outward propagating diurnal signal in the upper‐level clouds (diurnal pulse) is a prominent cyclical feature of tropical cyclones (TCs). This study examines relationships between diurnal pulses and TC intensity changes using satellite Infrared data from 2001 to 2018. The occurrence and duration of diurnal pulses 24 hr prior to or during TC intensity change are strongly correlated with TC intensification rate. Rapidly intensifying (RI) TCs have a markedly higher frequency (60%–80%) of very long‐duration pulse (15 hr) and significantly longer mean pulse duration than steady‐state (40%–50%) and gradually intensifying TCs (50%–60%). Long‐duration pulses are infrequent in weakening TCs (20%–30%). Diurnal pulse frequency and duration are highly correlated with the initial cloud‐top cooling rate and very cold‐cloud fraction in the inner core, but less related to the initial TC intensity. In short, strong diurnal pulsing of cold clouds is an evident signature prior to or during the RI of TCs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
