FORECASTING AIR QUALITY OVER THE UNITED STATES

Kenneth L. Scheie*, Atmospheric Modeling Division / RTP, NC
National Exposure Research Laboratory, Office of Research and Development

On assignment from the Ar Resources Laboratory, National Oceanic andAmospheric Adnhistration, U.S. Department of Commerce

NOAA AND EPA COLLABORATE ON AIR QUALITY FORECASTING

•	Increased public awareness of air quality issues has led to recent demand for short-term forecasts of air quality.

•	NOAA's National Weather Serve e (NWS) and U.S. EPA have begun a partnership to produce and operate a national system to
provide air quality forecast guidance.

•	A Memorandum of Agreement defines the roles of the organizations, including partnerships with state and local agencies and the
private sector who produce tailored air quality forecasts for their communities (see figure below).

•	The initial operational system will provide guidance on ground-level ozone for the northeastern U.S. by the end of 2004.

Simplifying EHAS Oju Atuiagmmtrt twtft Digital Dashtxaitis, p. 12

•	The forecast system will be extended to include fine particulate matter (PM2.5)
and the geographical coverage will be extended to the continental U.S. over the
next 5-7 years.

•	1-day air quality forecast guidance will be provided twice daily to support state
and local agencies who issue local forecasts of the Air Quality Index (AQI), based
upon the model guidance and other air quality data.

PARTNERSHIPS IN AIR QUALITY FORECASTING



NOAA

>	Devel op and evaluate tools for
national/state/local air quality
foie casting

>	Proyde ope rational air quality
model sand forecast pollutant
concentration fields with
national coverage

J

EPA

>	Mai n tai n cu rrent nati on al
emissions inventory

>	Maintain national air quality
monitoring databases

>	Dsseminate^nterpret national air
qu ali t y f ore ca st i nfo rm ati on

- AQI and links to public health

STATES / LOCALS

>	Proyde stated oca I emisa on s data

>	Provide stated oca I air quality
monitoring data

>	Provide local AQI Ibrecastsfwamings

PUBLIC and COMMERCIAL SECTORS

HOW WILL IT WORK?

•	NOAA/NWS runs their operational weather prediction model, Eta-12, for the U.S. four times
daily. Air quality predictions are made each day beginning with the 8:00 a.m. (EDT) weather
model output.

•	EPA provides source emissions data, air quality monitoring data and the air quality model

(Community Multiscale Air Quality model, CMAQ) developed by NOAA and EPA researchers.

•	NOAA/NWS runs CMAQ using forecasted weather information from Eta-12, along with source
emissions data, to produce gridded predictions of air quality, initially for the northeastern U.S.
Forecast guidance is available by 1:30 p.m. EDT and extends through the following day.

•	A later prediction cycle is run overnight, to proMde guidance for morning updates.

Example of Forecast Winds from ETA Model Example of Forecast Ozone from CMAQ Model

ETA Layer 1 Winds	CMAQ Layer I l

f T

• State and local air management agencies, as
well as commercial interests, "pull" the forecast
guidance from NOAA/NWS computers and issue
local AQI forecast.

WHO WILL USE THE FORECASTS?

•	Asthmatics, the elderly, parents of young
children, and others concerned about short-term
health impacts of poor air quality

•	Government and industry officials who consider
taking actions to reduce source emissions during
periods of poor air quality

•	Commercial print, TV, and radio media outlets
to broadcast the forecast information to the public

Ozone Air Quality Index

Air Quality

Air Quality Index

Good

0-50

Moderate

51-100

Unhealthy for
Sensitive Groups

101-150

Unhealthy

151 -200

Very Unhealthy

201 -300

•Generally, an ADI of 100for ozone corresponds to
an ozcne le/el of 0.08 parts per million (averaged
o/er8 houis).

IOMD0B)


-------