Publication Date

9-28-2020

Document Type

Article

Publication Title

Geophysical Research Letters

Volume

47

Issue

18

DOI

10.1029/2020GL089001

Abstract

Airborne cloud radar reveals extreme wildfire updrafts (~60 m s−1) and downdrafts (~30 m s−1) rivaling those in supercell thunderstorms. These extreme vertical velocities occur through a 3-km-deep layer and below the base of a developing pyrocumulonimbus (pyroCb) cloud, which extends to the tropopause at 12 km. In situ aircraft sampling shows updrafts are linked to large temperature and moisture excesses but remain subsaturated at flight level (i.e., below cloud base). Parcel estimates using the in situ data help explain how these “hot-moist” updrafts trigger the overlying pyroCb. The extreme vertical motions observed also pose a previously undocumented aviation hazard.

Funding Number

AGS‐1151930

Funding Sponsor

National Science Foundation

Keywords

extreme updrafts, fire behavior, pyrocumulus, remote sensing, wildfire plume dynamics

Comments

Copyright 2020 American Geophysical Union. All rights reserved.

Department

Meteorology and Climate Science

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