Microscale anthropogenic pollution modelling in a small tropical island during weak trade winds: Lagrangian particle dispersion simulations using real nested LES meteorological fields

Tropical islands are characterized by thermal and orographical forcings which may generate microscale air mass circulations. The Lesser Antilles Arc includes small tropical islands (width lower than 50 km) where a total of one-and-a-half million people live. Air quality over this region is affected by anthropogenic and volcanic emissions, or saharan dust. To reduce risks for the population health, the atmospheric dispersion of emitted pollutants must be predicted. In this study, the dispersion of anthropogenic nitrogen oxides (NOx) is numerically modelled over the densely populated area of the Guadeloupe archipelago under weak trade winds, during a typical case of severe pollution. The main goal is to analyze how microscale resolutions affect air pollution in a small tropical island. Three resolutions of domain grid are selected: 1 km, 333 m and 111 m. The Weather Research and Forecasting model (WRF) is used to produce real nested microscale meteorological fields. Then the weather outputs initialize the Lagrangian Particle Dispersion Model (FLEXPART). The forward simulations of a power plant plume showed good ability to reproduce nocturnal peaks recorded by an urban air quality station. The increase in resolution resulted in an improvement of model sensitivity. The nesting to subkilometer grids helped to reduce an overestimation bias mainly because the LES domains better simulate the turbulent motions governing nocturnal flows. For peaks observed at two air quality stations, the backward sensitivity outputs identified realistic sources of NOx in the area. The increase in resolution produced a sharper inverse plume with a more accurate source area. This study showed the first application of the FLEXPART-WRF model to microscale resolutions. Overall, the coupling model WRF-LES-FLEXPART is useful to simulate the pollutant dispersion during a real case of calm wind regime over a complex terrain area. The forward and backward simulation results showed clearly that the subkilometer resolution of 333 m is necessary to reproduce realistic air pollution patterns in this case of short-range transport over a complex terrain area. Globally, this work contributes to enrich the sparsely documented domain of real nested microscale air pollution modelling. This study dealing with the determination of the proper resolution grid and proper turbulence scheme, is of significant interest to the near-source and complex terrain air quality research community.

[1]  Y. Mahrer,et al.  Numerical Simulation of the Airflow Over Barbados , 1976 .

[2]  C. Barthe,et al.  Evaluating intense precipitation in high-resolution numerical model over a tropical island: impact of model horizontal resolution , 2014 .

[3]  G. Powers,et al.  A Description of the Advanced Research WRF Version 3 , 2008 .

[4]  L. Molina,et al.  Evaluation of WRF mesoscale simulations and particle trajectory analysis for the MILAGRO field campaign , 2009 .

[5]  D. Muñoz‐Esparza,et al.  Bridging the Transition from Mesoscale to Microscale Turbulence in Numerical Weather Prediction Models , 2014, Boundary-Layer Meteorology.

[6]  I. Renfrew,et al.  Thermally Induced Convective Circulation and Precipitation over an Isolated Volcano , 2016 .

[7]  Fuqing Zhang,et al.  Evaluation of Three Planetary Boundary Layer Schemes in the WRF Model , 2010 .

[8]  E. Mlawer,et al.  Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave , 1997 .

[9]  Fotini Katopodes Chow,et al.  Nesting large-eddy simulations within mesoscale simulations for wind energy applications , 2008 .

[10]  C. Willmott,et al.  A refined index of model performance , 2012 .

[11]  Thomas Plocoste,et al.  Evidence of the effect of an urban heat island on air quality near a landfill , 2014 .

[12]  Steven R. Hanna,et al.  Applications in Air Pollution Modeling , 1984 .

[13]  J. Dudhia.  Numerical Study of Convection Observed during the Winter Monsoon Experiment Using a Mesoscale Two-Dimensional Model , 1989 .

[14]  J. Dorville,et al.  Numerical Simulations of Island-Induced Circulations and Windward Katabatic Flow over the Guadeloupe Archipelago , 2014 .

[15]  James R. Anderson,et al.  A land use and land cover classification system for use with remote sensor data , 1976 .

[16]  David R. Stauffer,et al.  Numerical Prediction of Submesoscale Flow in the Nocturnal Stable Boundary Layer over Complex Terrain , 2012 .

[17]  J. Dudhia,et al.  Examining Two-Way Grid Nesting for Large Eddy Simulation of the PBL Using the WRF Model , 2007 .

[18]  C. Srinivas,et al.  Mesoscale atmospheric flow-field simulations for air quality modeling over complex terrain region of Ranchi in eastern India using WRF , 2015 .

[19]  J. Dudhia,et al.  Coupling an Advanced Land Surface–Hydrology Model with the Penn State–NCAR MM5 Modeling System. Part I: Model Implementation and Sensitivity , 2001 .

[20]  M. Jury,et al.  Mesoscale Structure of Trade Wind Convection over Puerto Rico: Composite Observations and Numerical Simulation , 2009 .

[21]  Song‐You Hong,et al.  The WRF Single-Moment 6-Class Microphysics Scheme (WSM6) , 2006 .

[22]  P. Zhu.  A multiple scale modeling system for coastal hurricane wind damage mitigation , 2008 .

[23]  V. Masson,et al.  A Diagnostic for Evaluating the Representation of Turbulence in Atmospheric Models at the Kilometric Scale , 2011 .

[24]  Gerhard Wotawa,et al.  The Lagrangian particle dispersion model FLEXPART-WRF version 3.0 , 2013 .

[25]  Numerical simulation of observed submesoscale plume meandering under nocturnal drainage flow , 2013 .

[26]  Michael R. Olson,et al.  Impact of regional transport on the anthropogenic and biogenic secondary organic aerosols in the Los Angeles Basin , 2015 .

[27]  C. Srinivas,et al.  Sensitivity Analysis of Atmospheric Dispersion Simulations by FLEXPART to the WRF-Simulated Meteorological Predictions in a Coastal Environment , 2016, Pure and Applied Geophysics.

[28]  H. V. Nguyen,et al.  Numerical simulations of island effects on airflow and weather during the summer over the island of Oahu , 2010 .

[29]  Xiao-Ming Hu,et al.  Evaluation of the updated YSU planetary boundary layer scheme within WRF for wind resource and air quality assessments , 2013 .

[30]  Yi-Leng Chen,et al.  Numerical Simulations of Island-Scale Airflow over Maui and the Maui Vortex under Summer Trade Wind Conditions , 2010 .

[31]  A. Stohl,et al.  Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2 , 2005 .

[32]  J. Mirocha,et al.  Nested high-resolution mesoscale/large eddy simulations in WRF: challenges and opportunities , 2010 .

[33]  J. Wyngaard.  Toward Numerical Modeling in the “Terra Incognita” , 2004 .

[34]  P. Marchesiello,et al.  Weather regimes and orographic circulation around New Caledonia. , 2010, Marine pollution bulletin.

[35]  Marc L. Fischer,et al.  Pollutant transport among California regions , 2013 .

[36]  D. Muñoz‐Esparza,et al.  Investigations of boundary layer structure, cloud characteristics and vertical mixing of aerosols at Barbados with large eddy simulations , 2015 .

[37]  Nested mesoscale to large-eddy simulations for wind energy applications , 2009 .

[38]  Trude Storelvmo,et al.  Orographic Precipitation in the Tropics: The Dominica Experiment , 2010 .

[39]  Yang Yang,et al.  Numerical simulations of the island-induced circulations over the Island of Hawaii during HaRP , 2005 .

[40]  N. Pineda,et al.  Using NOAA AVHRR and SPOT VGT data to estimate surface parameters: application to a mesoscale meteorological model , 2004 .

[41]  C. Vincent,et al.  Simultaneous nested modeling from the synoptic scale to the LES scale for wind energy applications , 2011 .

[42]  A. Oliphant,et al.  The evolution and structure of a tropical island sea/land-breeze system, northern Australia , 2001 .

[43]  Song-You Hong,et al.  Intercomparison of Planetary Boundary-Layer Parametrizations in the WRF Model for a Single Day from CASES-99 , 2011 .

[44]  R. Delmas,et al.  Numerical simulations of local circulations and pollution transport over Reunion Island , 2011 .

[45]  J. Smith,et al.  Nested Mesoscale Large-Eddy Simulations with WRF: Performance in Real Test Cases , 2012 .

[46]  K. Lilly.  The representation of small-scale turbulence in numerical simulation experiments , 1966 .

[47]  John S. Kain,et al.  The Kain–Fritsch Convective Parameterization: An Update , 2004 .

[48]  Charles N. Long,et al.  Modification of the Atmospheric Boundary Layer by a Small Island: Observations from Nauru , 2007 .

[49]  S. Chiao,et al.  Numerical Investigations of Convective Initiation in Barbados , 2013 .

[50]  B. Kosović,et al.  Resolved Turbulence Characteristics in Large-Eddy Simulations Nested within Mesoscale Simulations Using the Weather Research and Forecasting Model , 2014 .

[51]  R. Harley,et al.  Implementation of a high-resolution Source-Oriented WRF/Chem model at the Port of Oakland , 2014 .

[52]  Ronald B. Smith,et al.  The Wake of St. Vincent , 1997 .

[53]  J. Dudhia,et al.  A New Vertical Diffusion Package with an Explicit Treatment of Entrainment Processes , 2006 .

[54]  P. Zhu.  Simulation and parameterization of the turbulent transport in the hurricane boundary layer by large eddies , 2008 .

[55]  R. Rasmussen,et al.  A case study of radar observations and WRF LES simulations of the impact of ground-based glaciogenic seeding on orographic clouds and precipitation. Part I: Observations and model validations , 2014 .