Storm types in Bangladesh : duration, intensity and area of intra‐daily wet events - Archive ouverte HAL Access content directly
Journal Articles International Journal of Climatology Year : 2022

Storm types in Bangladesh : duration, intensity and area of intra‐daily wet events

(1) , ,
1

Abstract

We explore the characteristics of 96190 wet events (WE) defined as consecutive 3-hourly rainfall >= 1 mm/3h from a network of 34 stations across Bangladesh. Nearly 60% (5%) of wet events last <= 3 (>= 15) hours. The WEs are dynamically clustered into four "canonical" storm types (ST), mostly discretized by their duration, but also their mean and maximal intensity. While durations, total amounts and wet contiguous areas of WEs are positively related, their mean intensity is nearly independent of them. ~ 60% of WEs are associated with ST#1, that is short and small WEs and very low rainfall amounts (usually < 10 mm), ~15% of WEs are associated with either (ST#2) short/small WEs but with intense rainfall, probably mostly related to scattered thunderstorms, or (ST#3) longer/larger WEs but with less intense rainfall. The last ST (ST#4) is rare (~ 6%), related to very long durations and large wet areas, and includes the wettest WEs. It is especially frequent over southeastern Bangladesh. ST#2 to #4 contribute almost equally to the local-scale total amount of rainfall (27-29% each in mean) while ST#1, despite its individual low rainfall amount, still includes ~ 15% of it. ST#2 (ST#4) is related to the highest probability of occurrence of 3-hourly (daily) extremes. ST#4 occurrence is the most impacted by synoptic Indian lows/depressions as well as the main modes of intraseasonal variation, while ST#1 and #2 are also significantly impacted by intraseasonal modes but in reverse manner than ST#4.
Fichier principal
Vignette du fichier
Paper #1 BMD.pdf (6.97 Mo) Télécharger le fichier
Origin : Files produced by the author(s)

Dates and versions

hal-03766885 , version 1 (01-09-2022)

Identifiers

Cite

Vincent Moron, Nachiketa Acharya, Quamrul Sm Hassan. Storm types in Bangladesh : duration, intensity and area of intra‐daily wet events. International Journal of Climatology, In press, ⟨10.1002/joc.7835⟩. ⟨hal-03766885⟩

Collections

CNRS UNIV-AMU
1 View
4 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More