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  • Testing the efficacy of atmospheric boundary layer height detection algorithms using uncrewed aircraft system data from MOSAiC
Title: Testing the efficacy of atmospheric boundary layer height detection algorithms using uncrewed aircraft system data from MOSAiC
Abstract. During the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition, meteorological conditions over the lowest1 km of the atmosphere were sampled with the DataHawk2 (DH2) fixed-wing uncrewed aircraft system (UAS). These in situ observations of the central Arctic atmosphere are some of the most extensive to date and provide unique insight into the atmospheric boundary layer (ABL) structure. The ABL is an important component of the Arctic climate, as it can be closely coupled to cloud properties, surface fluxes, and the atmospheric radiationbudget. The high temporal resolution of the UAS observations allows us to manually identify the ABL height (ZABL) for 65 out of the total89 flights conducted over the central Arctic Ocean between 23 March and 26 July 2020 by visually analyzing profiles of virtual potentialtemperature, humidity, and bulk Richardson number. Comparing this subjective ZABL with ZABL identified by various previouslypublished automated objective methods allows us to determine which objective methods are most successful at accurately identifying ZABL inthe central Arctic environment and how the success of the methods differs based on stability regime. The objective methods we use are theLiu–Liang, Heffter, virtual potential temperature gradient maximum, and bulk Richardson number methods. In the process of testing these objectivemethods on the DH2 data, numerical thresholds were adapted to work best for the UAS-based sampling. To determine if conclusions are robust acrossdifferent measurement platforms, the subjective and objective ZABL determination processes were repeated using the radiosonde profileclosest in time to each DH2 flight. For both the DH2 and radiosonde data, it is determined that the bulk Richardson number method is the mostsuccessful at identifying ZABL, while the Liu–Liang method is least successful. The results of this study are expected to be beneficialfor upcoming observational and modeling efforts regarding the central Arctic ABL.  more » « less
Award ID(s):
1805569
PAR ID:
10350408
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Atmospheric Measurement Techniques
Volume:
15
Issue:
13
ISSN:
1867-8548
Page Range / eLocation ID:
4001 to 4022
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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