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Aviation and the urban environment. Julian Hunt University College London +Univs of Cambridge, Delft , Arizona State Cerc .co.uk (Former Director general UK Met Office). Aviation and meteorology. Progress leading to benefits to operations, business, society resulting from :
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Aviation and the urban environment Julian Hunt University College London +Univs of Cambridge, Delft , Arizona State Cerc .co.uk (Former Director general UK Met Office)
Aviation and meteorology • Progress leading to benefits to operations, business, society resulting from : • Improved forecasts, including ensembles and probabilities • Widely distributed real time data (eg sferics; data for passengers/airports) • Increased/improved use of new products (eg medium range, seasonal(?), environmental forecasts) • TRENDS are positive
Aviation and environment • 3 way interaction with society • Aviation <----- environment \ society / • Local /Global : aviation -> env. impacts society -> restrictions-> solutions? Trends for the future ?Compare with other Env impacts –transport’n; buildings
Urban Pollution Phoenix Los Angeles Salt Lake City Hong Kong (from Asia Weekly)
Aviation and urban environments • Impacts on society; local/regional pollution; noise; use of open/living space. • Urban/local environment impacts on aviation; complex winds , visibility; particles + future trends –expanding cities; climate change. • Solutions –restrictions,new locations of airports ; technology (fuels, engines,airframes ); urban warnings
Environmental science <society • Local ;air pollution emissions on ground and in bl. –adds/interacts with other sources transportation, buildings • improved monitoring;modelling/fcstg impact assessment,consultation,regulation? • Global ; green house gas emissions/impacts on atmosphere ->>intnl regulation (IPCC)->conseq for aviation
Features of ADMS-Airport An extension of ADMS-Urban – Gaussian type model nested in regional trajectory model Includes chemical reaction scheme, meteorological preprocessor, Monin-Obukhov and mixed layer scaling for boundary layer structure Allowance for up to 6500 sources: road (1500, each with up to 50 vertices), point, line area and volume (1500), grid sources (3000) and up to 500 runway sources (exhaust modelled as moving jets) Other airport features Hour by hour time varying data Multi-segment line sources e.g. taxi ways GIS link displays line, volume and runway sources
Features: MODELLING EXHAUSTS AS MOVING JETS & THE IMPACT OF WAKE VORTICES Models engine exhausts as moving jet sources As the aircraft accelerates buoyancy and emissions increasingly spread along the runway the exhaust jet sees a faster ambient wind speed, this affects the plume rise The plume from the faster aircraft rises less than that from a slower aircraft Allows for the impact wake vortices may have on jet plume rise
LHR2 diurnal variation ADMS-Airport (solid line) compared with measured data (dotted line), different runway use Departure on 27 R No departure on 27 R Arrival on 27R
Local –Regional meteo for aviation • Local -> wakes of structures near airports; urban bls day (1-2000m)-night (2layer form200/1000m- egLondon; New York) • Regional-> conv/divergence over/down wind of large urban areas (-> 800km);effects on extreme winds;seasonal effects on precip.pollution ; birds?etc • -> factors for future planning.
1. Regimes CASSOU & GULYARDI 2007
Aviation and related environmental technologies • Reduced emissions of pollutants via: Cleaner combustion, engine/aerodyn efficiency + new carbon neutral fuels ; on ground via renewable power ( Solar power to aircraft) • Reduced noise from new aero designs (2020?) –BUT LARGE INCREASE IN FLIGHTS Compare with large net reductions in surface emissions (transport/buildings)
Conclusions Key factors affecting aviation –environment interactions near airports /urban areas: Emissions including primary NO2 ->technology/controls +Background concentrations(regional policy) e.g. O3 , _ +Aircraft exhausts/designs /flight planning / -->minimise near field pollution and noise . -relate to global impacts of aviation ,(climate change ) and other environmental impacts -. Also need regulating, and integrated policies. Future possibilities ;technology, fuels, designs Surface efficiencies -> lower impact airports Or very low impact airports outside cities