The 3-Week-Long Transport History and Deep Tropical Origin of the 2021 Extreme Heat Wave in the Pacific Northwest

Autor(en)

Katharina Baier, Marcus Rubel, Andreas Stohl

Abstrakt

The heat wave in late June of 2021 (PNW21) set new temperature records in the Pacific Northwest (PNW). In Lytton the highest temperature ever recorded in Canada was measured. Several studies have already explored this extreme event in detail, however, here we compare the atmospheric air mass transport and heating processes associated with this heat wave with the 34 other most extreme heat events in the same region during the period 1960–2021, using a long backtracking time of 25 days. We found significant differences in the heat waves. During PNW21 most of the air was coming from the Philippine Sea, with more than 40% of the air located south of 15°N, and anomalous advection of sensible and latent heat from the Tropics was the dominant cause of PNW21. The latent heat was efficiently converted into sensible heat by precipitation, which was unique, as most other extremes experienced net diabatic cooling.

Organisation(en)

Institut für Meteorologie und Geophysik

Journal

Geophysical Research Letters

Band

50

ISSN

0094-8276

DOI

https://doi.org/10.1029/2023GL105865

Publikationsdatum

12-2023

Peer-reviewed

Ja

ÖFOS 2012

105206 Meteorologie

Schlagwörter

ASJC Scopus Sachgebiete

Geophysics, Allgemeine Erdkunde und Planetologie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/4206a956-6db5-4706-9a67-d847f43072aa