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Support Center for Regulatory Atmospheric Modeling (SCRAM)

Meteorological Data and Processors

Air quality models solve for the change in pollutant concentrations over time and space, and thereby require certain meteorological inputs that, in part, determine the formation, transport, and destruction of pollutant material. The requisite meteorological inputs vary by air quality model, but usually include information regarding wind speed and direction, vertical mixing, temperature and atmospheric moisture. While inputs for these air quality models are often derived from ambient measurements, it can be advantageous to use meteorological models to provide the necessary data.

This site provides databases and preprocessors based on these two main sources of inputs:

Observational Meteorological Data - Data consisting of physical parameters that are measured directly by instrumentation, and include temperature, dew point, wind direction, wind speed, cloud cover, cloud layer(s), ceiling height, visibility, current weather, and precipitation amount. These data and their associated meteorological data processors and accessory programs are usually required for dispersion models.

Meteorological Grid Models - Models that use mathematical formulations to simulate atmospheric processes such as the change of winds and temperature in time over an area or interest. These models are commonly used to develop meteorological inputs for photochemical models and some dispersion models, such as CALPUFF.

Meteorological Guidance - Provides guidance for the use of observational data in permit modeling, monitoring for modeling applications, and other related data procedures and quality assurance.

Additional information about meteorological data and processors can be found at Related Links