# Presentation: 929177

## Modeling and Forecasting Activities in Support of MAX-Mex Jerome Fast, Pacific Northwest National Laboratory

**Modeling and Forecasting Activities ****in Support of MAX-Mex**** *****Jerome Fast, Pacific Northwest National Laboratory***

## Why MAX-Mex for Modeling?

**Measurements**
- MAX-Mex, MCMA, MIRAGE-Mex, and INTEX-B investigators will collect extensive *concurrent *meteorology, chemistry, and particulate data using in-situ and remote sensing instrumentation deployed at surface sites and on research aircraft and satellites
- Particulate loading in Mexico City will likely produce strong signals on radiative forcing

***polluted day***

***unpolluted day***

## Why MAX-Mex for Modeling?

- G-1

- King-Air

- C-130

- DC-8

**Measurements**
- Coordination of research aircraft during a series of semi-Lagrangian experiments that will enable evaluation of predictions of particulate plume evolution - up to several days downwind
- surface (T0,T1, T2) and aircraft (G-1, King-Air) measurements during MAX-Mex are critical to obtain near-source data

## Why MAX-Mex for Modeling?

**Models**
- Evaluate performance of current state-of-the science models by quantifying the uncertainties in particulate mass, composition, size distribution, and optical properties
- Opportunities for collaborative research, such as comparing models with different aerosol process modules or comparing local/regional and global model predictions of particulate evolution
- Availability of global model output for use as boundary conditions of local and regional models
- Use MILAGRO data set as a test-bed to develop and evaluate new aerosol process modules

- [**Munoz-Alpizar et al., *****JGR*****, 2002**]

## Science Questions

**Science Questions**

**Aerosol Processing**
- Does aerosol “aging” occur mostly over Mexico City so that the downwind plume is simply diluted by transport and mixing processes?
- Or are aerosol properties evolving significantly downwind?  What are the processes responsible for evolving aerosol properties?
- How does biogenic emissions and other anthropogenic sources over central Mexico alter the evolution of particulates downwind?
- How do local recirculation processes, that mix aged air parcels with fresh emissions, affect aerosol properties?
- How can models be improved to better predict secondary organic aerosol (SOA) formation downwind of Mexico City?

- [**Tie, *****5th MM5/WRF Workshop*****, 2004]**

## Science Questions

**Climate**
- What is the impact of the Mexico City plume on local, regional, and global climate?
- Do global models adequately simulate the magnitude and distribution of aerosol radiative forcing downwind?
- Can information from Mexico City be used to better understand radiative forcing from other megacities?

- GCM Sulfate Column Burden from
- Mexico City (March - May)

- [**Barth and Church, *****JGR*****, 1999**]

- [**Raga et al., *****Atmos. Environ.*****, 2001**]

- Heating Rates from Aerosols Based on Radiative Transfer Model

## Local Meteorology

- We know much about the local meteorology from IMADA 1997 and other field campaigns, but
- Downwind regional transport and mixing processes largely unknown

**Teotihuacan**

**Chalco**

**Cuautitlan**

**UNAM**

**4700 m**

**3700 m**

**3500 m**

**2200 m**

**1300 m**

**IMADA 1997 radar wind profiler and sounding sites**

## Downwind Transport Pathways

- Predict downwind chemical evolution
- Determine transport pathways during months of Feb., Mar., and Apr.
- Modeling meeting held at UNAM in Mexico City on 15 March 2005

**chemical evolution as simulated by NCAR master mechanism over 5 days**
**13 out of 29 days (15 Feb - 14 Mar 2004) had outflow of CO column towards NE**
**dispersion for 14 days simulated between 24 Feb - 18 Mar 1997**
**forward and back trajectories (Apr -May 2003), NE and SW pathways**
**radar wind profiler or HYSPLIT (Feb - Mar 2002, 2003), large fraction towards NE**

**Madronich (NCAR), Tie (NCAR), Fast (PNNL), de Foy (MIT)**

## Effects of Local Emissions

- How do power plant and volcanic emissions effect particulate evolution?
- How frequently do these emissions mix with fresh pollutants over the city and with aged pollutants further downwind?

**< 3 km MSL layer**

**3-6 km MSL layer**

- Simulated SO2 19 LST 21 March 1997

- Anthropogenic Emissions

**3-6 km MSL layer**

**< 3 km MSL layer**

- Simulated SO2 11 LST 21 March 1997

**Tula Power Plant**

**Popocatepetl**

**Mexico City**

## Effects of Biomass Burning

- How does the mixing of biomass burning plumes and the Mexico City plume affect downwind particulate evolution?
- What is the relative contribution of biomass burning and Mexico City emissions on regional radiative forcing?

- MODIS Satellite Image 2 March 2004

**marine stratus common**

**biomass burning sites (red)**

## Effects of Clouds

- How do clouds affect aerosol properties over central Mexico and do does the Mexico City plume significantly alter cloud evolution?
- What is the fraction of boundary layer particulates vented into the free atmosphere through clouds?

- MODIS Satellite Image 31 March 2005

**Mexico City**

- clouds often form over the mountains surrounding Mexico City during the dry season

## MILAGRO Modeling Group

- Ernesto Caetano, Victor Magana, UNAM, MM5
- Benjamin de Foy: University of California - San Diego, MM5+FLEXPART+CAMx
- Bill Skamarock: NCAR / MMM, WRF
- Xuexi Tie: NCAR / ACD, WRF-chem
- Andreas Stohl: Norwegian Institute for Air Research, FLEXPART
- Greg Carmichael, Youhua Tang, Marcelo Mena: University of Iowa, STEM
- Peter Hess, Louisa Emmons: NCAR / ACD, MOZART
- Daniel Jacob: Harvard University, GEOS-chem
- Brad Pierce: NASA Langley, RAQMS
- Other investigators that may contribute:
- Georg Grell: NOAA, operational version WRF-chem
- Alma Hodzic, NCAR / ACD, CHIMERE (using MM5-UCSD as input)

_**MILAGRO and INTEX-B joint planning Meeting, Oct 24-26, Boulder, CO**_
- Co-chairs of Forecasting and Modeling Working Group
- Jerome Fast (PNNL) and Ernesto Caetano (UNAM)

## Forecasting Models

_**Likely Models**_
- MM5		Local - Regional, meteorology, x = 24, 8 km
- MM5+CAMx	Local - Regional, meteorology, chemistry, trajectories, 		dispersion, x = 36, 12, 3 km
- WRF 		Local - Regional, meteorology and tracers, x = 9, 3 km
- WRF-chem	Local - Regional, meteorology, chemistry, x = 6 km
- STEM		Regional - Continental, meteorology, tracers, chemistry, 		particulates, x = ? km
- FLEXPART	Global, passive scalar using GFS forecasts x = 1 degree
- MOZART	Global, chemistry, x = 2 degree
- GEOS-Chem	Global, chemistry, x ~ 50 km
- RAQMS		Global, chemistry, ozone assimilation, x = 2 x 2.5 degrees
_**Possible models**_
- WRF-chem	Continental, meteorology, chemistry, particulates, x = 40 km
- CHIMERE	Local - Regional, chemistry and particulates

- scale

## Forecasting Operations

**Veracruz Operations:**
- support G-1, C-130, King-Air, J-31
- use MILAGRO forecast models and other operational models to produce forecast of weather and location of Mexico City plume
**Houston Operations:**
- support DC-8
**Mexico City:**
- support surface measurements
**Video conferencing**
- daily weather briefing ~ 10-11 AM
- coordinate aircraft for next day
- forecasts focus on next day, but also produce 3-5 day forecasts

## Pre-Field Campaign Modeling

- PNNL’s version of WRF-chem community model, x = 18, 6, and 2 km
**Chemistry / Particulate Simulations**
- series of 2-day case study simulations during 1997 IMADA field campaign to examine evolution of trace gases, particulates, and radiative forcing over central Mexico
**Tracer Simulations**
- Series of 2-day simulations during 1997 IMADA field campaign period to examine pollutant pathways and model sensitivity to PBL formulations
- Series of month-long simulations to examine transport pathways and multi-day accumulation of pollutants over central Mexico

## Aircraft Scenarios: 1 March 1997

**Aircraft Scenarios: 1 March 1997**

- surface ozone 11 LT

**D**
**C**
**B**
**A**

- ozone 1600 m AGL 11 LT

**D**

**C**

**B**

**A**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T2**

**T1**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T0**

- west                                                              east

**G-1 Source Characterization**

**G-1 Lagrangian**

- good day for T0-T1-T2 Lagrangian scenario, 11 LT

**King-Air Overflights**

## Aircraft Scenarios: 1 March 1997

- good day for T0-T1-T2 Lagrangian scenario, 16 LT

- surface ozone 16 LT

**D**
**C**
**B**
**A**

- ozone 1600 m AGL 16 LT

**D**

**C**

**B**

**A**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T2**

**T1**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T0**

## Aircraft Scenarios: 13 March 1997

**Aircraft Scenarios: 13 March 1997**

- surface ozone 11 LT

**D**
**C**
**B**
**A**

- ozone 1600 m AGL 11 LT

**D**

**C**

**B**

**A**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T2**

**T1**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T0**

- west                                                              east

- Not a good day for T0-T1-T2 Lagrangian scenario, 11 LT

## Aircraft Scenarios: 13 March 1997

- surface ozone 16 LT

**D**
**C**
**B**
**A**

- ozone 1600 m AGL 16 LT

**D**

**C**

**B**

**A**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T2**

**T1**

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

- 7
- 6
- 5
- 4
- 3
- 2
- 1

**T0**

- west                                                              east

- Not a good day for T0-T1-T2 Lagrangian scenario, 16 LT

## Lagrangian Aircraft Flights

- 12 LT 27 February

- 12 LT 28 February

- 12 LT 1 March

- 12 LT 2 March

- synoptic conditions during March can be favorable for long-range transport of Mexico City plume to the NE over several consecutive days
- balloon trajectory will aid Lagrangian aircraft sampling strategy

**28****th**

**27****th**

**27****th**

**28****th**

**1****st**

**26****th**

**26****th**

##  Local Aerosol Processing

**Testing Conceptual Models**
**Then:**
- Model predictions employed to develop a conceptual model of diurnal evolution of pollutants in the valley
- Same-day recirculation of pollutants possible
- Little multi-day accumulation of pollutants
**Now:**
- 2006 campaigns will provide data to test these hypotheses
- Same-day recirculation will transport aged air parcels back over the city

## Summary

- MAX-Mex collaborative activities with the other MILAGRO scientists is a great opportunity for ASP to improve our understanding of aerosol evolution (particularly organic and elemental carbon) and radiative forcing associated with anthropogenic emissions
- MILAGRO data set will be useful in quantifying uncertainties in the predictions of particulate mass, composition, size distribution, and aerosol optical properties from current 3-D models and developing improved aerosol process modules