Environment Protection Authority of SA Meteorological Data Files For the Ausplume Air Dispersion Model Principal Contact Chris Purton May 2004 Ref No 20030765RA1B Table of Contents Table of Contents Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model 1. Introduction 1 2. Summary of Data Files 3 3. Adelaide Airport 1999/2000 (24 months) 4 4. Clare High School 1999/2000 (12 months) 7 5. Edinburgh Airfield 2000 10 6. Mount Gambier Airport 2000 13 7. Netley EPA 2003 16 8. Noarlunga 2002 19 9. Nuriootpa Viticulture 1999 22 10. Padthaway South 2000/2001 (12 months) 25 11. Port Augusta Arid Lands 2000 28 12. Renmark Airport 2000 31 13. Roseworthy College 2001/2002 (12 months) 34 14. Strathalbyn Racecourse 1999/2000 (12 months) 37 15. Whyalla Airport 2000 40 Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page: i Table of Contents Tables Table 2.1 Summary of Ausplume File Data 3 Table 3.1 Distribution of Meteorological Parameters with Stability for Adelaide Airport 1999/2000 (24 months) 4 Table 3.2 Wind Speed (m/s) versus Wind Direction for Adelaide Airport 1999/2000 (24 months) 5 Table 4.1 Distribution of Meteorological Parameters with Stability for Clare High School 1999/2000 (12 months) 7 Table 4.2 Wind Speed (m/s) versus Wind Direction for Clare High School 1999/2000 (12 months) 8 Table 5.1 Distribution of Meteorological Parameters with Stability for Edinburgh Airfield 2000 10 Table 5.2 Wind Speed (m/s) versus Wind Direction for Edinburgh Airfield 2000 11 Table 6.1 Distribution of Meteorological Parameters with Stability for Mount Gambier Airport 2000 13 Table 6.2 Wind Speed (m/s) versus Wind Direction for Mount Gambier Airport 2000 14 Table 7.1 Distribution of Meteorological Parameters with Stability for Netley EPA 2003 16 Table 7.2 Wind Speed (m/s) versus Wind Direction for Netley EPA 2003 17 Table 8.1 Distribution of Meteorological Parameters with Stability for Noarlunga 2002 19 Table 8.2 Wind Speed (m/s) versus Wind Direction for Noarlunga 2002 20 Table 9.1 Distribution of Meteorological Parameters with Stability for Nuriootpa Viticulture 1999 22 Table 9.2 Wind Speed (m/s) versus Wind Direction for Nuriootpa Viticulture 1999 23 Table 10.1 Distribution of Meteorological Parameters with Stability for Padthaway South 2000/2001 25 Table 10.2 Wind Speed (m/s) versus Wind Direction for Padthaway South 2000/2001 26 Table 11.1 Distribution of Meteorological Parameters with Stability for Port Augusta Arid Lands 2000 28 Table 11.2 Wind Speed (m/s) versus Wind Direction for Port Augusta Arid Lands 2000 29 Table 12.1 Distribution of Meteorological Parameters with Stability for Renmark Airport 2000 31 Table 12.2 Wind Speed (m/s) versus Wind Direction for Renmark Airport 2000 32 Table 13.1 Distribution of Meteorological Parameters with Stability for Roseworthy College 2001/2002 (12 months) 34 Table 13.2 Wind Speed (m/s) versus Wind Direction for Roseworthy College 2001/2002 (12 months) 35 Table 14.1 Distribution of Meteorological Parameters with Stability for Strathalbyn Racecourse 1999/2000 (12 months) 37 Table 14.2 Wind Speed (m/s) versus Wind Direction for Strathalbyn Racecourse 1999/2000 (12 months) 38 Table 15.1 Distribution of Meteorological Parameters with Stability for Whyalla Airport 2000 40 Table 15.2 Wind Speed (m/s) versus Wind Direction for Whyalla Airport 2000 41 Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page: ii Table of Contents Figures Figure 3.1 Wind Rose for Adelaide Airport 1999/2000 (24 months) 6 Figure 4.1 Wind Rose for Clare High School 1999/2000 (12 months) 9 Figure 5.1 Wind Rose for Edinburgh Airfield 2000 12 Figure 6.1 Wind Rose for Mount Gambier Airport 2000 15 Figure 7.1 Wind Rose for Netley EPA 2003 18 Figure 8.1 Wind Rose for Noarlunga 2002 21 Figure 9.1 Wind Rose for Nuriootpa Viticulture 1999 24 Figure 10.1 Wind Rose for Padthaway South 2000/2001 27 Figure 11.1 Wind Rose for Port Augusta Arid Lands 2000 30 Figure 12.1 Wind Rose for Renmark Airport 2000 33 Figure 13.1 Wind Rose for Roseworthy College 2001/2002 (12 months) 36 Figure 14.1 Wind Rose for Strathalbyn Racecourse 1999/2000 (12 months) 39 Figure 15.1 Wind Rose for Whyalla Airport 2000 42 Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page: iii Document History and Status Document History and Status Rev Description Author Rev’d App’d Date A Draft for Client Comment CMP 19/05/04 B Revised after Client Comments CMP MCK 31/05/04 Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page: iv Introduction 1. Introduction In September 2002, thirteen meteorological data files were produced for use with the Ausplume air dispersion model. The software used to produce the data files rejected days with missing essential data, namely air temperature, wind direction, wind speed, stability class or mixing height. The Environment Protection Authority of South Australia (EPA) have commissioned this study to review those data files with significant quantities of missing data, and increase the percentage of useable data, using techniques recommended by the US EPA. Where data have been rejected due to missing upper temperature profiles, which are used to calculate mixing height, the following procedure was adopted. Missing morning (23 UTC or 8:30 CST) upper air temperatures were replaced by manually interpolated data from the upper observations 12 hours before and after the missing data. Alternatively, where the evening (11 UTC or 20:30 CST) upper air temperature data were missing, then the preceding morning upper air temperature data were assumed to be valid for a 24 hour period. Where two or more successive upper air flights were missing, those entire days were omitted from the Ausplume dataset. A single missing surface data point on the hour was mathematically interpolated from adjacent data within 1 hour of the missing observation. Where surface data was missing for a 2 to 5 hour time period, manual interpolation was used. For data gaps exceeding 6 hours, manual interpolation was used where nearby surface meteorological data was available, otherwise the data, and that day, were omitted altogether. The software developed in 2002 managed anomalous results from standard Bureau of Meteorology surface observations when used in Ausplume dispersion modelling by pre-processing the wind speeds and directions in MS Excel as follows: • For all calms (speed 0.0 m/s) the reported wind direction of 0º was randomised to a direction between 0º to 360º. Where a preferred wind direction sector for light winds could be determined, then the randomisation was restricted to that sector. • For wind speeds of 0.5 m/s and greater, the wind direction in 10º increments from 10º to 360º was randomised to ±5º (except for 360º winds, which were left as reported). • Surface observations are usually timemarked in UTC. It was necessary to convert these times to CST in the MS Excel process. Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page : 1 Introduction The Pasquill-Gifford stability class is calculated in one of two ways. If Sigma Theta is available, the P-G stability class is calculated from that parameter using values from Tables 6.8a and 6.8b in “Meteorological Monitoring Guidance for Regulatory Modelling Application”, US EPA, February 2000. The division between day time and night time and Solar Altitude is based on the values of Latitude and Longitude previously entered in the “Parameter Input” table for the station location. If Sigma Theta is not available, then the P-G stability class is calculated using values from Table 6-3 and Table 6-5 (US EPA, February 2000). Mixing height is calculated from vertical temperature profile observations carried out by the Bureau of Meteorology. Software routines have not been provided for the other methods given in US EPA, February 2000, since there was no data available for testing. Mixing height calculation is complicated in South Australia by the fact that both standard observation release times (8:30 CST and 20:30 CST) usually coincide with a low level temperature inversion which inhibits mixing. The height of this overnight inversion is allotted an arbitrary height of 111 m by the program which produces the Ausplume datafile. As the day time temperatures increase, the hourly temperature is extended up the dry adiabat until it intersects the temperature profile at the mixing height for that hour. An upper limit of 4,000 m has been set for mixing height. One anomaly which has not been allowed for in the software is the passage of a cold front shortly after the 8:30 CST temperature sounding. In this case the surface temperature may not rise sufficiently to penetrate the early morning low level temperature inversion, leading to the mixing height remaining at the default 111 m all day. Environment Protection Authority of SA Meteorological Data Files for the Ausplume Air Dispersion Model MetDataReportMay2004.doc Revision: B Date: 31/05/04 Page : 2 Summary of Data Files 2. Summary of Data Files A summary of basic information on the available data files is given in Table 2.1 below.