# Presentation: 686519

## Dispersion and Air Quality Forecasting

***Development of the Tools for Operational Dispersion and Air Quality Forecasts***
**          **_**Organizations Involved**_
**	****Aeronomy Laboratory**
**	****Air Resources Laboratory**
**	****Environmental Technology Laboratory**
**	****Forecast Systems Laboratory**
**	****National Severe Storms Laboratory**
**	****National Centers for Environmental Prediction**

- Bruce Hicks and Rick Artz, ARL

## Dispersion and Air Quality Forecasting

**The Goal –** To develop and demonstrate operational
- models to predict changes in air quality, for both routine
- and emergency applications
**The Scales Involved –** From local to global, and from
- minutes to seasons
**The Successes So Far –** Models-3, VAFTAD*, HYSPLIT**

- *  VAFTAD – The Volcanic Ash Forecast Trajectory and Diffusion model
- ** HYSPLIT – The Hybrid Single Particle Lagrangian Integrated Trajectory model.

## Some Background

- NOAA/OAR has been an important civilian source of dispersion forecasts for more than ten years.  The VAFTAD and HYSPLIT models are now in the NCEP stable.
- OAR focused lab and field research has led to improved understanding of key atmospheric processes, which has translated directly into improved predictive capabilities.
- OAR has provided trial air quality forecasts for several years, focusing on ozone.  The initial focus was on Texas.  Subsequently, attention switched to east Tennessee (and the Smoky Mountains) and now to the Northeast.
- While perhaps less visible than the final model products, purposeful chemical and meteorological observations were and continue to be an integral part of the effort.
- The partnership with NCEP is long-standing.

## Dispersion Forecasting

- Homeland Security concerns have elevated issues related to atmospheric dispersion.
- OAR scientists have been the source of many (perhaps the majority) of the approaches used to model dispersion.  This development started in the 1950s.  Today, many agencies have their own specialized capabilities.
- Together with NOS, NWS and OAR are working with OFCM to sort out the models now in common use.  Most of these models are used for assessment and preparedness applications.  Few are operational.  Fewer still are used in a forecast mode.

## Current NWS Operational Dispersion Models 

- For many years, the OAR/ARL VAFTAD* model has been used by the NWS in its volcanic ash plume forecasting program.  Recently, the HYSPLIT model has been added to the NWS suite.
- HYSPLIT also serves as the engine behind the dispersion forecasting capability of China and Australia.  It is the model favored by the WMO in its Regional Specialized Meteorological Center (run jointly by ARL and NCEP), and is used operationally by the Comprehensive Test Ban Treaty Office and several components of  the Dept. of Defense.
- *  The Volcanic Ash Forecast Trajectory and Diffusion model.

## Local (Urban) Issues

- Fears arise concerning terrorist attacks – especially in urban areas.  The grid size of forecast models must be finer, and dispersion capabilities need to be tailored to the urban area of interest.
-   Existing local-scale dispersion models almost universally employ turbulence descriptions based on classical micro-meteorological studies – in near-perfect conditions.  Extension to complex urban situations has yet to be well tested. As an intermediate step, dispersion routines need to be data assimilative.

## Operations at the World Trade Center site.  ARL supports EPA studies.

**Notes:**
Top left – the plume.  Bottom left – an ARL wind sensor near ground zero.  Right, an example of a plume estimate, using a data assimilative model.

## Daily average PM-10 concentrations

- for 14 November 2001

- Preliminary data
- Do not cite or distribute.

**Notes:**
Plots of this kind are being used to guide clean-up efforts and to look for adverse health effects.  

## In Concept, a Joint  Forecast System 

**Atmospheric System**
**Global**
**NOGAPS, NGM**
**Integrated Global Observing System (Weather, Climate, Ocean)**
**Data Assimilation (JCSDA)**
**CONUS**
**COAMPS, AVN/MRF**
**CONUS Observing System**
**Data Assimilation (JCSDA)**
**Regional**
**COAMPS, ETA-12km, NMM-4km, MM5/WRF, etc.**
**Regional Mesonet**
**Data Assimilation**
**Local**
**COAMPS-1km, MM5-1km/WRF-1km, etc.**
**Local Micronet**
**Data Assimilation**
**ALOHA/CAMEO, etc.**

- Partnership with Navy, Air Force, Army

**Notes:**
The concept is an ensemble system, making use of all of the best products available.

## Urban Test-Bed Conceptto test and develop the next generation of models

- Urban Test-Bed Conceptto test and develop the next generation of models

- Urban Observations
- High resolution winds, temperature and humidity
- Wind profilers, temperature/humidity profilers
- Radar – SPY-1, WS88D
- In situ temperature and humidity
- ACARS (commercial aviation data)
- Chemical/biological sensing
- In situ Chem/Bio sensors

- Partnership with Army, Navy, DTRA, UCAR

**Notes:**
Two sites have been instrumented so far, as part of a test project – on the Commerce Building and at the National Academy.

## The Path to Operations 

**NWS-OAR Milestones:**
- 2002:	OFCM model assessment
- 	Improved HYSPLIT integration with NWS
- 2003:	Oklahoma City Testbed observations
- 2004:	Development of NOS/OAR/NWS model product suite
- 	  (ALOHA/HYSPLIT/WRF-Chem)
- 	Washington Testbed study
- 2005:	Improved NOAA product suite

## Air Quality Forecasting

- There is a strong demand for forecasts, especially by
- local forecasters, but also by industry.  It is the intent to
- provide a uniform system for predicting ozone concentrations and evaluating model products, inputs to the decision-making process adopted by local air quality forecasters (often private).
- Many western countries are moving towards including
- air quality in their forecasting suite – e.g. Canada, Australia,
- the Netherlands, Denmark, . . . . .

## The 2002 Pilot Program

- This is an OAR-NWS partnership.
- Under the Energy Initiative, an intensive study of air
- chemistry and meteorology in the Northeast will occur this year.  Part of the program will entail trial air quality forecasting.
- The study will concentrate on factors that influence
- meteorology and air quality in a coastal area.  The NOAA RV Ronald H. Brown will be used, supported by an array of remote sensing and surface observations.

## Step 1 – A Baseline

- There is growing collaboration with Canada  . . . .
- NCEP needs a baseline
- model, against which to
- judge improvements.  It
- has been proposed that
- the Canadian CHRONOS*
- model serve in this way.
- *  CHRONOS – The Canadian
- Hemispheric and Regional Ozone and NOx System.

**Notes:**
CHRONOS is the model run in Canada.  Its domain stretches across all of eastern North America – or most of it (not sure about Florida).

## Step 2 – Apply Models

- Three modeling systems are being tested this year –
-   A fully Eulerian model developed by the Forecast Systems Laboratory.
-   An operational forecast version of the Models-3 air quality assessment model (MAQSIP), developed by MCNC (North Carolina) with the Air Resources Laboratory.
-   A hybrid system, coupling Lagrangian meteorology with fully Eulerian chemistry, developed by the Air Resources Laboratory.

## Step 3 – Evaluate the Models

- In 2002, extensive field data will be collected in the
- Northeast, against which the models will be evaluated.
- Techniques for assessing the performance of air quality
- forecast models are being developed.  At present, there
- is no accepted air quality equivalent to a “skill score.”
- The principal laboratories involved – AL, ARL, ETL, FSL, NCEP.

## The Path to Operations 

**Milestones:**
- 2002:	Integrated observations – Northeast Energy Initiative
- 	Model application
-       	Model verification and validation
- 	Concept of Operations
- 2003:  	Develop skill scores for air quality forecasts
- 2004:  	Extension of application to particles
- 2005:  	Operational air quality forecasts