Atmospheric Density Currents: Impacts on Aviation over NSW and ACT

Wang, Shuang

Atmospheric Density Currents: Impacts on Aviation over NSW and ACT

Wang, Shuang

Permalink

Publication Type:: Thesis
Issue Date:: 2019

Open Access

Copyright Clearance Process

Recently Added
In Progress
Open Access

This item is open access.

Adobe PDF

Download contents and abstractAdobe PDF (359.14 kB)

Adobe PDF

Download thesisAdobe PDF (10.61 MB)

View statistics

Full metadata record

Field	Value	Language
dc.contributor.author	Wang, Shuang
dc.date.accessioned	2020-08-25T02:51:36Z
dc.date.available	2020-08-25T02:51:36Z
dc.date.issued	2019
dc.identifier.uri	http://hdl.handle.net/10453/142339
dc.description	University of Technology Sydney. Faculty of Science.	en_AU
dc.description.abstract	Three main types of density currents (DCs) which have significant impacts for aviation are investigated in detail over New South Wales (NSW) state of Australia and Australian capital Territory (ACT) in the research. The three types of density currents are southerly busters (SBs) along the coastal NSW, thunderstorm downbursts over north-western NSW and easterly DCs over Canberra. The research take advantage of the recently available Himawari-8 high temporal- and spatial-resolution satellite data, Sydney wind profiler data, Doppler radar data, radiosonde data, half hourly METAR and SPECI aviation from observation data Bureau of Meteorology Climate zone, synoptic weather charts and other observational data. In addition, simply model for density currents, global data assimilation system (GDAS) meteorological model outputs, and the Australian Community Climate and Earth-System Simulator (ACCESS) operational model products are employed in the research. Based on the impacts on aviation, for SBs and strong SBs (SSBs), when wind directions are between 160 degrees to 210 degrees, SBs are the average winds or gusty wind is >= 14.9 m/s (29 knots or 54 km/h), SSBs are the average winds or gusty winds more than 20.5 m/s (40 knots or 74 km/h). For easterly DCs, when wind directions are between 070 degrees to 150 degrees, the average winds or gusty wind is >= 7 m/s (13 knots or 23 km/h). For thunderstorms downbursts, damaging winds are the average winds or gusty winds more than 20.5 m/s (40 knots or 74 km/h) in any direction. The results of this research show that the data analyses support the widespread view that the SB is a DC, coastally trapped by the Great Dividing Range. In addition, solitary waves develop ahead of SB in a shallow and stable prefrontal boundary layer. A simplified density current model is applied to SBs, SSBs and easterly DCs. The model results have been verified by the observations. The results that are solely model based also suggest that the solitary waves travel at speeds about 20% faster than the DCs which is consistent with the high-resolution satellite data and shows the solitary waves moving increasingly ahead of the leading edge of the DCs. The damaging winds caused by thunderstorm downbursts are DCs. The characteristics are presented, and forecast parameters and indices are discussed. Finally, the climatological trends for SBs and SSBs at Sydney airport are examined statistically by using permutation testing and wavelet analysis. The results show that there is significant increase in SBs over last 49 years, however, the SSBs show no significant trend over the same period.	en_AU
dc.format	Thesis (PhD)
dc.language.iso	en_US	en_US
dc.relation	https://opus.lib.uts.edu.au/bitstream/10453/142339/2/02whole.pdf
dc.rights	au.edu.uts.lib/ppc
dc.rights	The author owns the copyright in this thesis including all reproduction and reuse rights for the work. The work may not be altered without the permission of the copyright owner. Attribution is essential when quoting or paraphrasing from this thesis.
dc.rights	info:eu-repo/semantics/openAccess
dc.title	Atmospheric Density Currents: Impacts on Aviation over NSW and ACT	en_AU
dc.type	Thesis
utslib.copyright.status	open_access	*

Abstract:

Three main types of density currents (DCs) which have significant impacts for aviation are investigated in detail over New South Wales (NSW) state of Australia and Australian capital Territory (ACT) in the research. The three types of density currents are southerly busters (SBs) along the coastal NSW, thunderstorm downbursts over north-western NSW and easterly DCs over Canberra. The research take advantage of the recently available Himawari-8 high temporal- and spatial-resolution satellite data, Sydney wind profiler data, Doppler radar data, radiosonde data, half hourly METAR and SPECI aviation from observation data Bureau of Meteorology Climate zone, synoptic weather charts and other observational data. In addition, simply model for density currents, global data assimilation system (GDAS) meteorological model outputs, and the Australian Community Climate and Earth-System Simulator (ACCESS) operational model products are employed in the research. Based on the impacts on aviation, for SBs and strong SBs (SSBs), when wind directions are between 160 degrees to 210 degrees, SBs are the average winds or gusty wind is >= 14.9 m/s (29 knots or 54 km/h), SSBs are the average winds or gusty winds more than 20.5 m/s (40 knots or 74 km/h). For easterly DCs, when wind directions are between 070 degrees to 150 degrees, the average winds or gusty wind is >= 7 m/s (13 knots or 23 km/h). For thunderstorms downbursts, damaging winds are the average winds or gusty winds more than 20.5 m/s (40 knots or 74 km/h) in any direction. The results of this research show that the data analyses support the widespread view that the SB is a DC, coastally trapped by the Great Dividing Range. In addition, solitary waves develop ahead of SB in a shallow and stable prefrontal boundary layer. A simplified density current model is applied to SBs, SSBs and easterly DCs. The model results have been verified by the observations. The results that are solely model based also suggest that the solitary waves travel at speeds about 20% faster than the DCs which is consistent with the high-resolution satellite data and shows the solitary waves moving increasingly ahead of the leading edge of the DCs. The damaging winds caused by thunderstorm downbursts are DCs. The characteristics are presented, and forecast parameters and indices are discussed. Finally, the climatological trends for SBs and SSBs at Sydney airport are examined statistically by using permutation testing and wavelet analysis. The results show that there is significant increase in SBs over last 49 years, however, the SSBs show no significant trend over the same period.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/142339