The Chiricahua Gap and the Role of Easterly Water Vapor Transport in Southeastern Arizona Monsoon Precipitation

TitleThe Chiricahua Gap and the Role of Easterly Water Vapor Transport in Southeastern Arizona Monsoon Precipitation
Publication TypeJournal Article
Year of Publication2017
AuthorsRalph FM, Galarneau T.J
JournalJournal of Hydrometeorology
Volume18
Pagination2511-2520
Date Published2017/09
Type of ArticleArticle
ISBN Number1525-755X
Accession NumberWOS:000417351800010
Keywordserrors; extreme precipitation; field; models; moisture; name 2004; north-american monsoon; rainfall; sensitivity; Southwest
Abstract

Between North America's Sierra Madre and Rocky Mountains exists a little-recognized terrain "gap.'' This study defines the gap, introduces the term "Chiricahua Gap,'' and documents the role of easterly transport of water vapor through the gap in modulating summer monsoon precipitation in southeastern Arizona. The gap is near the Arizona-New Mexico border north of Mexico and is approximately 250 km wide by 1 km deep. It is the lowest section along a 3000-km length of the Continental Divide from 168 to 45 degrees N and represents 80% of the total cross-sectional area below 2.5 km MSL open to horizontal water vapor transport in that region. This study uses reanalyses and unique upper-air observations in a case study and a 15-yr climatology to show that 72% (76%) of the top-quartile (decile) monsoon precipitation days in southeast Arizona during 2002-16 occurred in conditions with easterly water vapor transport through the Chiricahua Gap on the previous day.

DOI10.1175/jhm-d-17-0031.1
Short TitleJ. Hydrometeorol.
Student Publication: 
No