Dispersion modelling in complex terrain: Sensitivity studies with the CALMET model
Author: Matic Ivančič
Milan Vidmar Electric Power Research Institute
Ljubljana, 15.12.2011
Matic Ivančič Ljubljana, 15.12.2011
CONTENTES
Introduction - air pollution modeling
CALMET model Three different wind field
initializations Results
Matic Ivančič Ljubljana, 15.12.2011
INTRODUCTION
Air pollution modeling: Advection with wind
3D wind fields Dispersion in cross-section
Stability of atmosphere
ALADIN - operative meteorological forecast in Slovenia
Matic Ivančič Ljubljana, 15.12.2011
INTRODUCTION
ALADIN – CALMET – CALPUFF are online coupled
Two-days prediction are available on web: www.okolje.info
Matic Ivančič Ljubljana, 15.12.2011
CALMET
Diagnostic wind model (DFW)
3 main parts: Initial field (first guess) First step Second step
Matic Ivančič Ljubljana, 15.12.2011
First step
Kinematic effects of terrain
Slope flows Blocking effects 3D divergence minimization
Matic Ivančič Ljubljana, 15.12.2011
Second step Interpolation
Smoothing
O’Brien adjustment of vertical velocities
2D divergence minimization
Matic Ivančič Ljubljana, 15.12.2011
Divergence minimization
Varitional technique (Sherman 1978) Minimization of following functional:
Strong condition:
New functional:
Matic Ivančič Ljubljana, 15.12.2011
Divergence minimization Solution with EL equations :
numerical solution for λ:
Matic Ivančič Ljubljana, 15.12.2011
TEST AREA
Šoštanj basin
Biggest thermal power plant in Slovenia
9 meteorological and air quality stations
Matic Ivančič Ljubljana, 15.12.2011
9 surface stations – only 6 stations has representative wind data
Matic Ivančič Ljubljana, 15.12.2011
Radio-sounding measurements in Zagreb
Matic Ivančič Ljubljana, 15.12.2011
ALADIN points
Matic Ivančič Ljubljana, 15.12.2011
3 DIFFERENT WIND FIELD INITIALIZATIONS
A Data from surface stations and upper air data from radio-sounding
B Meteorological analysis from ALADIN
C Combination of data from surface stations and meteorological analysis from ALADIN
Matic Ivančič Ljubljana, 15.12.2011
Experiment A
First guess: from measurements First step:
Terrain effects 3D divergence minimization
Second step: Again interpolation of measurements
Matic Ivančič Ljubljana, 15.12.2011
Experiment B
First guess is prepared with data from model ALADIN
First step
Second step
Matic Ivančič Ljubljana, 15.12.2011
Experiment C
First guess: from model ALADIN First step:
Terrain effects 3D divergence minimization
Second step: Import measurements with objective
analysis procedure
Matic Ivančič Ljubljana, 15.12.2011
RESULTS – stability calculation
0%
10%
20%
30%
40%
50%
very unstable unstable slightlyunstable
neutral slightly stable stable
PGT stability class
A
B
C
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YA
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YC
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YD
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YE
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YF
Matic Ivančič Ljubljana, 15.12.2011
Wind rose – station YG
Matic Ivančič Ljubljana, 15.12.2011
CALPUFF results
Dispersion calculation of SO2
Matic Ivančič Ljubljana, 15.12.2011
CONCLUSION
It is hard to judge which model initialization gives better results
Radio-sounding measurements are far away ALADIN analysis have better space but time
interpolation required ALADIN predictions may improve results –
hourly data Case B: for areas without meteorological
measurements and for predictions Case C: maximum number of inputs
Matic Ivančič Ljubljana, 15.12.2011
Acknowledgements
Author would like to thank the Environmental Agency of the Republic of Slovenia for providing all fields from ALADIN model
Matic Ivančič Ljubljana, 15.12.2011
THANK YOU FOR YOUR ATTENTION
Matic Ivančič Ljubljana, 15.12.2011
LITERATURE Sherman, C. A., 1978: A mass-consistent model for
wind fields over complex terrain. J. Appl. Meteor., 17, 312–319.
Scire J. S., F. R. Robe, M. E. Fernau, R. J. Yamartino, 2000: A User’s Guide for the CALMET Meteorological Model, Version 5, Earth Tech, Inc, Concord.
Scire J. S., D. G. Strimaitis, R. J. Yamartino, 2000: A User’s Guide for the CALPUFF Dispersion Model, Vesrion 5, Earth Tech, Inc, Concord.