Science Inventory

ATMOSPHERIC MODEL EVALUATION

Impact/Purpose:

The goal of this task is to thoroughly characterize the performance of the emissions, meteorological and chemical/transport modeling components of the Models-3 system, with an emphasis on the chemical/transport model, CMAQ. Emissions-based models are composed of highly complex scientific hypotheses concerning natural processes that can be evaluated through comparison with observations, but not validated. Both performance and diagnostic evaluation together with sensitivity analyses are needed to establish credibility and build confidence within the client and scientific community in the simulations results for policy and scientific applications. The characterization of the performance of Models-3/CMAQ is also a tool for the model developers to identify aspects of the modeling system that require further improvement.

Description:

Evaluation of the Models-3/CMAQ is conducted in this task. The focus is on evaluation of ozone, other photochemical oxidants, and fine particles using data from both routine monitoring networks and special, intensive field programs. Two types of evaluations are performed here: performance (operational) evaluations and diagnostic evaluations. In performance (operational) testing modeled pollutant concentrations of regulatory interest are compared to observations (right answer). Diagnostic testing examines the model's capability to simulate processes that affect the results (right answer for right reason). Model sensitivity analyses to characterize model response to uncertainties are also conducted in this task with an emphasis on characterizing the response to emissions reductions or the control response. Model evaluation technique development for more advanced performance statistics and diagnostic model evaluation procedures are conducted in this task as well. Specific, enduring research elements include ADP and GIS support, model evaluation data generation, model evaluation technique development (diagnostic techniques and space-time techniques), performance/diagnostic model evaluation studies, and uncertainty/sensitivity analysis. Research sections with tasks and objectives are developed under each of the research elements.

Record Details:

Record Type: PROJECT
Start Date: 07/01/1998
Completion Date: 10/01/2003
Record ID: 56139

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL EXPOSURE RESEARCH LABORATORY

ATMOSPHERIC MODELING DIVISION