# Presentation: 931677

## Atmospheric Program

## Air Quality Program Vision

- Build a program that takes advantage of current research expertise
- advanced instrumentation, high performance computing, modeling uncertainty, indoor environment
- Participate significantly in important air quality field studies
- Develop a framework for assessing air quality modeling uncertainty
- Participate in building the next generation, science-based air quality model

## Atmospheric Program

- Areas of Expertise

- Advanced
- Instrumentation

- Carbon
- Cycling

- Emissions

- Model
- Uncertainty

- Aerosols

- Modeling

## AtmosphericProgram Structure

**Air Quality**
**Urban - Regional**

**Global Carbon**
**Cycle**

**Advanced **
**Computing**

**Strong Interactions**
**With Indoor **
**Environment Dept**

## Talk Outline

- Program Goals
- Program Structure
- Program Capabilities
- Current Research

## Atmospheric Program

- Research Efforts and Capabilities
- PERF Meeting
- March 10, 1999

## DOE-GRI Wyoming Air Quality Study (WAQS)

- Lawrence Berkeley National Laboratory
- Envair
- GRI/Radian Corporation

## WAQS Objectives

- To determine impacts on air quality, visibility, and acid deposition of current oil and gas production and planned oil and gas development(OGD) in Wyoming
- To continue to assess the air quality, visibility, and acid precipitation benefits of alternative emissions control strategies
- To evaluate and improve the reliability of the estimates made

## WAQS Task Structure

- Problem Definition and Informational Needs
- Estimate Emissions
- Air Quality Modeling Review and Evaluation
- Meteorological Modeling Review and Evaluation
- Review Monitoring Data
- Conduct Data Analysis
- Synthesis

## Outdoor-Indoor PM-2.5 Study: Objective

- To develop and field test a physically-based semi-empirical model to predict distributions of indoor PM-2.5 in single family residential buildings based on outdoor measurements of chemically resolved PM-2.5 made at stationary monitoring sites.

## Proposed Research-Highly Leveraged

- Collaboration with San Joaquin Valley Study (SJVS) Investigators
-    $27.5M multi-year, multi-institutional outdoor air study
- Partially funded by Office of Oil and Gas Exploration and Production and Western States Petroleum Association

## Task Structure

- Planning and Preparation for Field Experiments
- Characterize aerosol changes across the building shell
- Build mass balance model based on field experiments
- Validate model with Housing Sample

## Major DeliverablesA Semi-empirical Model

- Developed and field tested to predict distributions of concentrations of outdoor PM-2.5 in residential buildings based upon measured outdoor measurements of PM-2.5
- Field-tested, validated, and verified
- Useful for calculating exposure to PM-2/5
- Contributes to enhancing scientific understanding imperative for standard setting that protects health and is cost effective

## Feedback to Climate Change From Carbon in Forest Soils

- •

- Globally, forest soils contain roughly as much

- carbon as there is CO2 in the atmosphere; hence

- there is the potential for significant feedback to

- climate change.

- •

- Field studies will be initiated along elevation

- gradients in C Reserve System Forests and US

- National Parks in California and US National

- Forests in Colorado.

- •

- Observations and experiments  will determine short

- and  long  term responses of soil carbon to changes

- in climate and plant species composition.

- •

- Results will be combined with separate work on

- plant species responses to predict changes in soil

- carbon under global warming.

- CO

- 2

- Soil

- Carbon

## Carbon Cycle Research

- Biospheric-Atmospheric Feedbacks
- Climate Forcing from Aerosols

- 2

## Implementation of Radiative Transfer Modeling in AQM

- 2

- Creation of a radiative transfer module to be implemented in current Air Quality Models.
- Based on a proven method.
- Computational burden not too severe.
- Flexible parameter input scheme.
- 	The module is derived from an existing two-stream method radiative transfer simulation program.
- Selection of most important parameters to model radiative transfer.
- Sensitivity analysis was performed for the radiative transfer module input parameters.
- Principal Component Analysis was performed on Southern California UV radiometer data to identify most important factors.
- 	Most important parameters are:
- aerosols characteristics,
- ozone optical depth, and
- surface albedo.

## Motivations

-    Data concerning the distribution of pollutants in the atmosphere is often scarce. Light absorption by pollutants affects actinic flux and  photolytic rates.
- Determine the contributions of various pollutants to light absorption using light intensity measurements in the UV.
- Measurement at ****** = 300, 305, 311, 317, 325, 332 368 nm**.
- Correlate the contributions to simple measurements.
- Compare a site with urban polluted air to a nearby site with relatively clean air.
- Multifilter radiometers installed at Mt Wilson and Riverside, CA.

## Optical Depth

- 	**The relationship between the direct irradiance and the solar beam path length through the atmosphere (Beer-Lambert Law) is used to compute the total optical depth.**
**	****To ensure data quality, a selection algorithm is used and Langley plots are checked visually.**
**	****The average optical depth distribution does not allow pollutant identification.**

## Optical Depth Correlations

**	****Correlations between optical depths simultaneously measured at different wavelengths carry  information about the components responsible for the optical depths.**
**	****Event correlations are computed for each two-by-two wavelength combination.**
**	****Strong correlations are found for optical depths at ******** > 300 nm. Weaker correlations are found between optical depths at ******** > 300 nm and optical depths at ******** > 300 nm.**

## Principal Component Analysis

**	****A reference frame transformation is performed to diagonalize correlation matrix****. Hence, the components in the new frame are independent.**
**	****The eigenvalues show the amount of variation associated with each component. ****The largest components carry 90.9% and 7.6% of the variation in Riverside, and 75.8% and 15.2% at Mt Wilson.**
**	****The wavelength contributions to the components suggest that the first two  components correspond to aerosols and ozone absorption.**

## Rapid Mapping of Gas Species in Ambient Air

**Toxic release monitoring**
- Improvement over conventional fence line monitoring
- Preemptive solution for indoor/outdoor worker safety
- Accurate measurement of integrated release
**Tunable diode laser (IR absorption ) instrument:**
- Measure 60 open paths every 6 sec
-  Detection limit ~ 5 ppm-m (CH4)
-  Reconstruct map using computed tomography
- Simultaneous measurement of known tracer gas release yields release rate of other gas species