Transcript 2006-2008 GEOS-Chem Simulations for CMAQ Initial and

CMAS Conference
2006-2008 GEOS-Chem Simulations for
CMAQ Initial and Boundary Conditions
1Yun-Fat
Lam, 1Joshua S. Fu, 2Daniel J. Jacob,
3Carey Jang and 3Pat Dolwick
1 University
of Tennessee, Knoxville
2 Harvard University
3 EPA-OAQPS
Oct 11, 2010
Outline of talk
1. Background and Motivation
–
Long-range transport
–
Increase in background concentration
2. Development & Methodology
–
New CB05 with AE5 mapping table
3. Global and Regional Model Configurations
–
GEOS-Chem and CMAQ simulation
4. Sensitivity to Initial & Boundary Conditions
5. Conclusions
Why boundary condition is important
to U.S. air quality?
Canadian and Mexican
pollution enhancement
• Long-range transport of air
pollutant 1
• Enhancement of background
pollutants concentration 2
– The Canadian and Mexican
pollution enhancement averages
3-4 ppb in the US in summer 3
– peaking at 33 ppb in upstate New
York (on a day with 75 ppb total
ozone) and 18 ppb in
1Heald,
C.L., et al., J. Geophys. Res. (2003), Mian Chin, et al., Atmos. Chem. Phys. (2007)
R., Atmos. Envir. (2004), Ordonex C., et al., Geophys. Res. L. (2007)
3 Huiqun Wang, et al., Atmos. Envir. (2009), 43, 1310–1319
2Vingarzan
GEOS-Chem Simulations
• 2005–2008 GEOS-Chem simulations
– To study the inter-annual variability of boundary
condition from each bound (North, East, South
and West)
• Propose a fixed domain for sharing CMAQ initial and
boundary conditions using 34-layer IC/BC file
– Study the impacts of using 24L IC/BC Vs.
34Lto24L
– Identify the effects of this technique to CMAQ
output.
Global Model Configuration
Emissions Summary
GEOS-Chem v8-03-01
• Domain:
Globe
• Horizontal Grid Spacing: 2 ° x 2.5°
• Horizontal Coordinate:
Lat x Lon
• Vertical Grid Spacing:
54
layers
• Simulation Period:
2005-2008
• Meteorological Input:
GEOS5
Inter-annual Variability of Ozone (Avg JFM)
CMAQ BCON
EAST
25
25
25
10
2007
2008
2006
2007
20
2008
15
10
5
10 ppb 5
-
-
0.00
0.05
0.10
O3 Concentration (ppm)
Elevation (km)
15
20
2006
Elevation (km)
Elevation (km)
20
25
2005
2006
2005
2005
WEST
NORTH
15
10
5
2005
2006
2007
2008
20
Elevation (km)
SOUTH
9ppb
-
0.00
0.05
0.10
O3 Concentration (ppm)
2007
2008
15
10
5
0.00
0.05
0.10
O3 Concentration (ppm)
0.00
0.05
0.10
O3 Concentration (ppm)
Inter-annual Variability of Ozone (Avg AMJ)
CMAQ BCON
EAST
SOUTH
25
25
2005
2006
2005
2005
2007
2008
20
2008
5
0.00
0.05
0.10
O3 Concentration (ppm)
15
10
2005
2006
20
Elevation (km)
10
2007
2008
2006
2007
Elevation (km)
15
20
2006
Elevation (km)
Elevation (km)
20
WEST
NORTH
25
25
15
10
15
10
5
5
5
-
-
-
0.00
0.05
0.10
O3 Concentration (ppm)
0.00
0.05
0.10
O3 Concentration (ppm)
All less than 5 ppb
2007
2008
0.00
0.05
0.10
O3 Concentration (ppm)
Inter-annual Variability of Ozone (Avg JAS)
CMAQ BCON
EAST
SOUTH
2005
2005
2006
2007
2006
2007
2006
2007
5
0.00
0.05
0.10
O3 Concentration (ppm)
15
10
20
15
10
15
10
5
5
5
-
-
-
0.00
0.05
0.10
O3 Concentration (ppm)
0.00
0.05
0.10
O3 Concentration (ppm)
All less than 5 ppb
2007
2008
2008
2008
Elevation (km)
Elevation (km)
10
20
2005
2006
Elevation (km)
20
2008
15
25
2005
Elevation (km)
20
25
25
25
WEST
NORTH
0.00
0.05
0.10
O3 Concentration (ppm)
Inter-annual Variability of Ozone (Avg OND)
CMAQ BCON
EAST
25
25
2005
2006
2007
2006
2007
20
5
Elevation (km)
Elevation (km)
10
12ppb
-
15
10
20
5
-
0.00
0.05
0.10
O3 Concentration (ppm)
25
2005
2006
2008
2008
15
25
2005
Elevation (km)
20
WEST
NORTH
0.00
0.05
0.10
O3 Concentration (ppm)
15
10
2005
2006
2007
2008
20
Elevation (km)
SOUTH
15
10
5
5
-
0.00
0.05
0.10
O3 Concentration (ppm)
2007
2008
0.00
0.05
0.10
O3 Concentration (ppm)
Development of GEOS-Chem to CMAQ
IC/BCs Module (Geo2CMAQ)
• Newest version – 2010 (version 2.2)
– Tropopause determining algorithm to remove
stratospheric effects from GEOS-Chem
– Update to the newest version of GEOS-Chem v8-0301
– Add CB05-AE5 conversion table
Introducing the concept of tropopause
• Imaginary layer that separates between stratosphere
and troposphere.
• Abrupt change of physical phenomenon
• Three different ways to define tropopuase
– Temperature1 (1937) => Thermal tropopuase
– PV2 (1959) => Dynamical tropopause
– Ozone3 (1995) => Ozone tropopause
1 1Stohl A.,
et al., J. Geophys. Res. (2003)
(1980), WMO (1986)
3Bethan, S., et al, J. R. Meteorol. Soc (1995)
2Shapiro
Vertical Profile and Tropopause
Determining Algorithm
• Determining
tropopause based on
the dynamical
searching on
maximum rate of
change of slope
July 25, 2002 (Trinidad Head, CA)
(ppm)
(ppmv)
0.00
0.16
40
CO
CO
Temperature
Temp.
Ozone
Ozone
Dynamical Tropopause
Elevation (km)
30
20
Thermal Tropopause
Ozone Tropopause
10
0
0
2
4
6
OzoneOzone
Concentration
(ppmv)
Concentration
8
(ppmv)
-60 -30 0 20 40
(Degree
(DegreeC)
C)
• Abrupt change of
ozone and CO
concentrations
occurred
• Each grid in
downscaling has its
own ozone
tropopause height, so
temporal and spatial
Geo2CMAQ Conversion tool
3Lam,
Y. F. and J. S. Fu (2009)., Atmos. Chem. Phys., 10, 4013-4031, doi:10.5194/acp-10-4013-2010
CB05-AE5 Conversion Table
??The ratio between Aged
SOA and Non-aged SOA??
CMAQ Model Configurations
CMAQ V4.7
•
•
•
•
•
•
•
Meteorological Input
Domain:
Horizontal Grid Spacing:
Horizontal Coordinate:
Vertical Grid Spacing:
Simulation Period:
IC/BC:
MM5 V3.7
CONUS
36 km
LCC
24 layers
2005
GEOS-Chem 2005
Two IC/BC scenarios were performed:
1. 24 Layer IC/BC using 24-layer MCIP product
2. 24 Layer IC/BC using average layer collapsing
technique from 34-layer MCIP & 34-layer IC/BC
24-layer Vs 34-layer (sample point)
EAST
25
20
Elevation (km)
Elevation (km)
24L
34L
15
10
WEST
25
24L
20
34L
Elevation (km)
25
20
NORTH
15
10
25
24L
20
34L
Elevation (km)
SOUTH
15
10
15
10
5
5
5
5
0
0.00
0
0.00
0
0.00
0
0.00
0.05
Ozone (ppm)
0.10
0.05
0.10
Ozone (ppm)
0.05
0.10
24L
34L
Ozone (ppm)
The major effect will be on
23rd and 24th layer
0.05
Ozone (ppm)
0.10
Comparison of “24L” – “24L=>34L”
Surface Concentration
JAN – O3
JUL – O3
JAN – SO2
JUL – SO2
Summary
1. The GEOS2CMAQ program improves the downscaling
process for generating GEOS-Chem IC/BC. In this study,
total of four years of GEOS-Chem simulation have been
performed
– The variability of average seasonal background
boundary concentration of ozone is about 10–12 ppbv
– Mostly occurred at the upper level of North and South
bounds
2. The newt approach for generating the IC/BC using full
sigma level gives a better data portability. It also makes it
easier to share IC/BC data with other researchers.
•
•
Only required very limited processing.
It only changes the surface ozone level by less than
0.25 ppb from original method.
3. We are in the progress to construct a website to share the
Acknowledgement
• USEPA’s STAR and GCAP (phase 1 and phase 2)
funding supports
Q&A
Thank you!