INTEGRATION OF MEASURED, MODELLED

1
INTEGRATION OF MEASURED, MODELLED REMOTELY
SENSED AIR QUALITY DATA IMPACTS ON THE SOUTH
AFRICAN HIGHVELD Kubeshnie Bhugwandin -
November 2009
2
Overview

• Introduction
• Study Area
• Aim of Study
• Data
• CALPUFF Modelling
• Results Discussion
• Potential Risk Assessment

3
Introduction

• S.A. is a major regional contributor to aerosols
  and trace gases
• Mpumalanga Highveld is one of the most highly
  industrialised areas in Southern Africa
• Emission densities ranked amongst the highest in
  the world
• Fifteen of S.A.s coal fired power stations are
  located here

4
Study Area
5
Study Area
6
Introduction

• Several datasets have been created
• Never been an integration of datasets derived
  from the different methods of air quality (AQ)
  monitoring evaluation
• This study compared AQ data using a GIS in order
  to determine the most accurate estimate of ground
  level SO2 and NO2 concentrations

7
Aim of Study

• Overarching aim is to improve modelled air
  quality predictions using measured data to
  integrate measured, modelled and satellite data
  to evaluate impacts of power station emissions on
  ecosystems and human health
• Ultimate objective is to credibly predict
  concentrations without reference to fixed ground
  based monitoring stations

8
Objectives

• To determine whether-
• Modelled ground level air pollution concentration
  fields can be improved by utilising measured
  data
• Satellite retrievals of SO2 and NO2
  concentrations are representative of surface
  concentrations and
• Integration of available datasets with a GIS will
  improve the evaluation of impacts from power
  station emissions on ecosystems and health

9
Data

• Data information for the project
• Eskom database of continuous ground based
  measurements for 2003
• Modelled data derived from Calpuff dispersion
  modelling exercise conducted by Eskom
• SAWS meterological data as an input for
  dispersion modelling
• SCIAMACHY retrievals from TEMIS website

10
ESKOM AQ Monitoring Network
11
Eskom Monitoring

• Eskom AQ monitoring operations accredited with
  SANAS.
• Monitoring stations serviced and maintained
  according to ISO9001 site service procedures
• Monitoring stations visited once every 2 weeks
  for routine equipment service and maintenance,
  analyser for zero and span checks and data
  collection.

12
CALPUFF Background

• CALPUFF is a USEPA approved modelling suite.
• Comprises of CALMET (meteorological model),
  CALPUFF (dispersion model) and CALPOST (result
  processing module)
• Is a regional Langragian Puff model suitable for
  application in modelling domains between 50 to
  200km.
• Model is able to account for spatial variability
  of meteorological conditions, dry deposition and
  dispersion over a variety of differing land
  surfaces

13
CALPUFF Background

• The area modelled was approx 160 km (east-west)
  by 108 km (north-south)
• The Cartesian receptor grid selected had a
  resolution of 1770 m by 1770 m
• SAWSs ETA-model was used to provide upper air
  met data for 12 locations
• Surface met data were included for 9 Eskom
  monitoring stations and 10 SAWS stations

14
Validation of Model
15
Validation of Model
16
Distribution Tail Analysis
17
Distribution Tail Analysis
18
Distribution Tail Analysis
19
Distribution Tail Analysis
20
Distribution Tail Analysis
21
Distribution Tail Analysis
22
Impact Assessment

• SO2 NO2

23
Impact Assessment

• Model values were replaced with measured values
• Inverse distance weighted interpolation technique
  utilised

24
SO2 Standards
25
NO2 - Standards
26
DEAT Tolerances
27
DEAT 35Oug/m3 - Health
28
DEAT 125ug/m3 - health
29
DEAT 50ug/m3
30
EC Guideline 20ug/m3
31
EC Guidline 30 ug/m3
32

• Thank you !