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Abstract Airborne Doppler radar observations of the wind field in the tropical cyclone boundary layer (TCBL) during the landfall of Hurricane Ida (2021) are examined here. Asymmetries in tangential and radial flow are governed by tropical cyclone (TC) motion and vertical wind shear prior to landfall, while frictional effects dominate the asymmetry location during landfall. Strong TCBL inflow on the offshore‐flow side of Ida occurs during landfall, while the location of the peak tangential wind at the top of the TCBL during this period is located on the onshore‐flow side. A comparison of these observations with a numerical simulation of TC landfall shows many consistencies with the modeling study, though there are some notable differences that may be related to differences in the characteristics of the land surface between the simulation and the observations here.
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Gradient Winds and Neutral Flow Dawn‐Dusk Asymmetry in the Auroral Oval During Geomagnetically Disturbed Conditions
Key Points Gradient wind balance is dominant in the neutral flow in the auroral oval in disturbed conditions The cyclonic flow on the dawn side is severely limited in magnitude by gradient wind constraints The anticyclonic flow on the dusk side can show anomalous super‐gradient behavior that accommodates significantly larger flow speeds
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- Award ID(s):
- 2012994
- PAR ID:
- 10457305
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 127
- Issue:
- 1
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2021JA029936
