Modeling the exceptional south Foehn event (Garmij) over the Alborz Mountains during the extreme forest fire of December 2005

Abbas Mofidi (), Iman Soltanzadeh (), Yadollah Yousefi (), Azar Zarrin (), Mohsen Soltani, Jafar Masoompour Samakosh (), Ghasem Azizi and Samuel Miller

Natural Hazards: Journal of the International Society for the Prevention and Mitigation of Natural Hazards, 2015, vol. 75, issue 3, 2489-2518

Abstract: An exceptional southerly Foehn in the Alborz Mountains in northern Iran is investigated by using a combination of observations, reanalysis, and simulation data. A synoptic analysis is used as well as a high-resolution numerical modeling to clarify the Foehn event at different scales. The event resulted in an extensive and high-intensity fire in the Gilan and Mazandaran forests in northern Iran. The results indicate that a mechanically driven Foehn occurred in the Alborz Mountains during December 16–18, 2005. On the synoptic scale, the Foehn event occurred due to the presence of high pressure over the interior regions of Iran and lee cyclone over the southern Caspian Sea, with a strong south–north pressure gradient across the Alborz Mountains. In the mesoscale, the results suggest that mountain waves generated over the northern slopes of the Alborz Mountains are the primary source of the localized southerly wind maximum around the lee side of Alborz. A numerical simulation reveals that strong meridional surface pressure differences along with southerly flow, which is blocked upstream of the Alborz Mountains, result in higher nonlinearity and create large-amplitude vertically propagating mountain waves over the Alborz Mountains. The study also indicates that the wave-breaking region on the lee side with a critical level ranging from 600 to 400 hPa is responsible for reflecting the mountain wave energy back to the ground and for creating severe downslope wind (Garmij) in leeward side of Alborz Mountains. The Foehn event first appeared early on December 16, due to a wave-breaking at 550 hPa in western part of the Alborz Mountains. Copyright Springer Science+Business Media Dordrecht 2015

Keywords: Foehn; Forest fires; Downslope wind; Alborz Mountains; Mountain wave; WRF model (search for similar items in EconPapers)
Date: 2015
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://hdl.handle.net/10.1007/s11069-014-1440-9 (text/html)
Access to full text is restricted to subscribers.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:spr:nathaz:v:75:y:2015:i:3:p:2489-2518

Ordering information: This journal article can be ordered from
http://www.springer.com/economics/journal/11069

DOI: 10.1007/s11069-014-1440-9

Access Statistics for this article

Natural Hazards: Journal of the International Society for the Prevention and Mitigation of Natural Hazards is currently edited by Thomas Glade, Tad S. Murty and Vladimír Schenk

More articles in Natural Hazards: Journal of the International Society for the Prevention and Mitigation of Natural Hazards from Springer, International Society for the Prevention and Mitigation of Natural Hazards
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().