Sub-synoptic circulation variability in the Himalayan extreme precipitation event during June 2013

Ramesh K. Vellore; Jagat S. Bisht; Raghavan Krishnan; Umakanth Uppara; Giorgia Di Capua; Dim Coumou

doi:10.1007/s00703-019-00713-5

Sub-synoptic circulation variability in the Himalayan extreme precipitation event during June 2013

Ramesh K. Vellore^*
, Jagat S. Bisht
, Raghavan Krishnan
, Umakanth Uppara
, Giorgia Di Capua
, Dim Coumou

^*Corresponding author for this work

Water and Climate Risk

Research output: Contribution to Journal › Article › Academic › peer-review

328 Downloads (Pure)

Abstract

This study investigates the sub-synoptic scale circulation aspects associated with the extreme rainfall event occurred over the North Indian state of Uttarakhand located in the western Himalayas (WH) during the 15–18 June 2013 period. A diagnosis based on hourly ERA5 reanalyzed circulation products archived on finer grids reveals that sustenance of heavy rains during the event period is supported by a propensity of cyclonic vorticity sources channeled toward the WH region through a narrow quasi-steady conduit in the lower troposphere from the ISM circulation. The equatorward segregating mesoscale potential vorticity (PV) structures from the quasi-stationary upper level PV anomaly (trough) during the event administered two pathways for vorticity sources. The first pathway is from the base of the trough culminating into longer horizontal conduit path from the western Arabian Sea, lending perpetual cyclonic vorticity support to the ISM environment. The second pathway is from the right flank of the trough, which promotes sustained environment of deeper mesoscale convergence zone, potentially unstable atmosphere and strong ascent over the Uttarakhand region. The convergence zone is potentially viewed as a region for strong monsoon and extratropical circulation interactions to occur on finer horizontal scales of motion, where significant vertical synchronization of positive PV advection is realized during the 16–17 June 2013 period. In addition to orographic precipitation enhancements, deeper advective synchronization noticed at sub-synoptic time periods is accredited to the nearly doubling 24-h rainfall amounts in the foothill region of Uttarakhand during the event period. The ERA5 diagnosed diabatic heating additionally indicates that precipitating systems at higher (foothill) elevations contribute to upper (lower) tropospheric heat sources.

Original language	English
Pages (from-to)	631-665
Number of pages	35
Journal	Meteorology and Atmospheric Physics
Volume	132
Issue number	5
Early online date	25 Nov 2019
DOIs	https://doi.org/10.1007/s00703-019-00713-5
Publication status	Published - Oct 2020

Funding

The authors acknowledge The Director, Indian Institute of Tropical Meteorology (IITM), Pune, India, for the encouragement and support for this work. We thank the anonymous reviewers for providing valuable comments. This work is carried out under the Ministry of Earth Sciences (MoES), Government of India?Belmont Project Globally Observed Teleconnections and their role and representation in Hierarchies of Atmospheric Models (GOTHAM). The authors also acknowledge TRMM dataset archived and distributed by the Goddard Distributed Active Archive Center (https://pmm.nasa.gov), EUMETSAT for the METEOSAT-7 imagery datasets (https://eoportal.eumetsat.int) and the fifth-generation of ECMWF atmospheric reanalyzes (ERA5) products obtained from the Copernicus Climate Change Service Climate Data Store (CDS; https://cds.climate.copernicus.eu). Utilization of high performance computing facility at IITM for processing the datasets is acknowledged. The authors acknowledge The Director, Indian Institute of Tropical Meteorology (IITM), Pune, India, for the encouragement and support for this work. We thank the anonymous reviewers for providing valuable comments. This work is carried out under the Ministry of Earth Sciences (MoES), Government of India—Belmont Project Globally Observed Teleconnections and their role and representation in Hierarchies of Atmospheric Models (GOTHAM). The authors also acknowledge TRMM dataset archived and distributed by the Goddard Distributed Active Archive Center ( https://pmm.nasa.gov ), EUMETSAT for the METEOSAT-7 imagery datasets ( https://eoportal.eumetsat.int ) and the fifth-generation of ECMWF atmospheric reanalyzes (ERA5) products obtained from the Copernicus Climate Change Service Climate Data Store (CDS; https://cds.climate.copernicus.eu ). Utilization of high performance computing facility at IITM for processing the datasets is acknowledged. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Funders
ECMWF
Goddard Distributed Active Archive Center
Ministry of Earth Sciences
Indian Institute of Technology Madras
Ministry of Coal, Government of India
European Organization for the Exploitation of Meteorological Satellites

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 14 Life Below Water

Access to Document

10.1007/s00703-019-00713-5

Vellore2020_Sub-synopticCirculationVariabilityInTheHimalayanExtremePrecipitationEventDuringJune2013Final published version, 24.6 MBLicence: Article 25fa Dutch Copyright Act

Persistent URL (handle)

Persistent link

Cite this

@article{dc40df92a62942e2a5f5aa647e6c8111,

title = "Sub-synoptic circulation variability in the Himalayan extreme precipitation event during June 2013",

abstract = "This study investigates the sub-synoptic scale circulation aspects associated with the extreme rainfall event occurred over the North Indian state of Uttarakhand located in the western Himalayas (WH) during the 15–18 June 2013 period. A diagnosis based on hourly ERA5 reanalyzed circulation products archived on finer grids reveals that sustenance of heavy rains during the event period is supported by a propensity of cyclonic vorticity sources channeled toward the WH region through a narrow quasi-steady conduit in the lower troposphere from the ISM circulation. The equatorward segregating mesoscale potential vorticity (PV) structures from the quasi-stationary upper level PV anomaly (trough) during the event administered two pathways for vorticity sources. The first pathway is from the base of the trough culminating into longer horizontal conduit path from the western Arabian Sea, lending perpetual cyclonic vorticity support to the ISM environment. The second pathway is from the right flank of the trough, which promotes sustained environment of deeper mesoscale convergence zone, potentially unstable atmosphere and strong ascent over the Uttarakhand region. The convergence zone is potentially viewed as a region for strong monsoon and extratropical circulation interactions to occur on finer horizontal scales of motion, where significant vertical synchronization of positive PV advection is realized during the 16–17 June 2013 period. In addition to orographic precipitation enhancements, deeper advective synchronization noticed at sub-synoptic time periods is accredited to the nearly doubling 24-h rainfall amounts in the foothill region of Uttarakhand during the event period. The ERA5 diagnosed diabatic heating additionally indicates that precipitating systems at higher (foothill) elevations contribute to upper (lower) tropospheric heat sources.",

author = "Vellore, \{Ramesh K.\} and Bisht, \{Jagat S.\} and Raghavan Krishnan and Umakanth Uppara and \{Di Capua\}, Giorgia and Dim Coumou",

year = "2020",

month = oct,

doi = "10.1007/s00703-019-00713-5",

language = "English",

volume = "132",

pages = "631--665",

journal = "Meteorology and Atmospheric Physics",

issn = "0177-7971",

publisher = "Springer-Verlag Wien",

number = "5",

}

TY - JOUR

T1 - Sub-synoptic circulation variability in the Himalayan extreme precipitation event during June 2013

AU - Vellore, Ramesh K.

AU - Bisht, Jagat S.

AU - Krishnan, Raghavan

AU - Uppara, Umakanth

AU - Di Capua, Giorgia

AU - Coumou, Dim

PY - 2020/10

Y1 - 2020/10

N2 - This study investigates the sub-synoptic scale circulation aspects associated with the extreme rainfall event occurred over the North Indian state of Uttarakhand located in the western Himalayas (WH) during the 15–18 June 2013 period. A diagnosis based on hourly ERA5 reanalyzed circulation products archived on finer grids reveals that sustenance of heavy rains during the event period is supported by a propensity of cyclonic vorticity sources channeled toward the WH region through a narrow quasi-steady conduit in the lower troposphere from the ISM circulation. The equatorward segregating mesoscale potential vorticity (PV) structures from the quasi-stationary upper level PV anomaly (trough) during the event administered two pathways for vorticity sources. The first pathway is from the base of the trough culminating into longer horizontal conduit path from the western Arabian Sea, lending perpetual cyclonic vorticity support to the ISM environment. The second pathway is from the right flank of the trough, which promotes sustained environment of deeper mesoscale convergence zone, potentially unstable atmosphere and strong ascent over the Uttarakhand region. The convergence zone is potentially viewed as a region for strong monsoon and extratropical circulation interactions to occur on finer horizontal scales of motion, where significant vertical synchronization of positive PV advection is realized during the 16–17 June 2013 period. In addition to orographic precipitation enhancements, deeper advective synchronization noticed at sub-synoptic time periods is accredited to the nearly doubling 24-h rainfall amounts in the foothill region of Uttarakhand during the event period. The ERA5 diagnosed diabatic heating additionally indicates that precipitating systems at higher (foothill) elevations contribute to upper (lower) tropospheric heat sources.

AB - This study investigates the sub-synoptic scale circulation aspects associated with the extreme rainfall event occurred over the North Indian state of Uttarakhand located in the western Himalayas (WH) during the 15–18 June 2013 period. A diagnosis based on hourly ERA5 reanalyzed circulation products archived on finer grids reveals that sustenance of heavy rains during the event period is supported by a propensity of cyclonic vorticity sources channeled toward the WH region through a narrow quasi-steady conduit in the lower troposphere from the ISM circulation. The equatorward segregating mesoscale potential vorticity (PV) structures from the quasi-stationary upper level PV anomaly (trough) during the event administered two pathways for vorticity sources. The first pathway is from the base of the trough culminating into longer horizontal conduit path from the western Arabian Sea, lending perpetual cyclonic vorticity support to the ISM environment. The second pathway is from the right flank of the trough, which promotes sustained environment of deeper mesoscale convergence zone, potentially unstable atmosphere and strong ascent over the Uttarakhand region. The convergence zone is potentially viewed as a region for strong monsoon and extratropical circulation interactions to occur on finer horizontal scales of motion, where significant vertical synchronization of positive PV advection is realized during the 16–17 June 2013 period. In addition to orographic precipitation enhancements, deeper advective synchronization noticed at sub-synoptic time periods is accredited to the nearly doubling 24-h rainfall amounts in the foothill region of Uttarakhand during the event period. The ERA5 diagnosed diabatic heating additionally indicates that precipitating systems at higher (foothill) elevations contribute to upper (lower) tropospheric heat sources.

UR - https://www.scopus.com/pages/publications/85076218948

UR - https://www.scopus.com/pages/publications/85076218948#tab=citedBy

U2 - 10.1007/s00703-019-00713-5

DO - 10.1007/s00703-019-00713-5

M3 - Article

AN - SCOPUS:85076218948

SN - 0177-7971

VL - 132

SP - 631

EP - 665

JO - Meteorology and Atmospheric Physics

JF - Meteorology and Atmospheric Physics

IS - 5

ER -

Sub-synoptic circulation variability in the Himalayan extreme precipitation event during June 2013

Abstract

Funding

UN SDGs

Access to Document

Persistent URL (handle)

Other files and links

Fingerprint

Cite this