Ocean-Atmosphere Trajectories of Extended Drought in Southwestern North America

dc.contributor.author

Parsons, LA

dc.contributor.author

Coats, S

dc.date.accessioned

2022-11-02T13:22:02Z

dc.date.available

2022-11-02T13:22:02Z

dc.date.issued

2019-08-27

dc.date.updated

2022-11-02T13:22:01Z

dc.description.abstract

Multiyear droughts are a common occurrence in southwestern North America (SWNA), but it is unclear what causes these persistent dry periods. The ocean-atmosphere conditions coinciding with droughts have traditionally been studied using correlation and composite methods, which suggest that cool conditions in the tropical Pacific are associated with SWNA droughts and warm conditions are associated with wet periods in SWNA. Nevertheless, the extent to which multiyear droughts are truly consistent with this paradigm remains unknown. This is, in part, because the temporal trajectory of ocean-atmosphere conditions during these dry periods have not been sufficiently characterized. Here we examine the continuum of ocean-atmosphere trajectories before, during, and after multiyear droughts in SWNA using observation-based data and an ensemble of climate model simulations from the Community Earth System Model. An examination of sea surface temperature patterns at the beginning, middle, and end of SWNA droughts shows that an El Niño event tends to precede SWNA droughts, a cool tropical Pacific occurs during droughts, and central Pacific El Niño events end droughts. However, moderate El Niño events can occur in the middle of persistent droughts, so a warm tropical Pacific does not always end these dry periods. These findings are important for drought predictability and emphasize the need to improve simulations of the magnitude, life cycle, and frequency of occurrence of El Niño events.

dc.identifier.issn

2169-897X

dc.identifier.issn

2169-8996

dc.identifier.uri

https://hdl.handle.net/10161/26196

dc.language

en

dc.publisher

American Geophysical Union (AGU)

dc.relation.ispartof

Journal of Geophysical Research: Atmospheres

dc.relation.isversionof

10.1029/2019JD030424

dc.title

Ocean-Atmosphere Trajectories of Extended Drought in Southwestern North America

dc.type

Journal article

duke.contributor.orcid

Parsons, LA|0000-0003-3147-0593

pubs.begin-page

8953

pubs.end-page

8971

pubs.issue

16

pubs.organisational-group

Duke

pubs.organisational-group

Staff

pubs.publication-status

Published

pubs.volume

124

Files

Original bundle

Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Parsons_2019_JGRA_SWNA_Drought.pdf
Size:
1.67 MB
Format:
Adobe Portable Document Format