Atmospheric Science Overview

Exponent provides advanced atmospheric sciences consulting services for clients around the world. Our staff specializes in air quality modeling, emissions modeling, air quality and meteorological measurements, air permitting and licensing, meteorological modeling and analysis, forensic meteorology and climatology.

Our Work

Our staff has modeled some of the toughest air quality issues including industrial plumes, dense gases, photochemical reactions, mobile sources, forest fires, explosions, radioactive releases, and odors. In addition to site-specific assessments, our staff has dealt with regional-scale and global-scale air quality issues. Exponent scientists have been involved in computer-based air modeling since its inception in the early 1970s. Our staff has developed or contributed to many of the USEPA-recommended models and algorithms including CALPUFF, PRIME building downwash and overwater dispersion.
Exponent staff also made contributions to the development of the earliest photochemical grid models, and they have been continuously involved in the evolution, development, application and evaluation of these models as well. We investigate accidental releases of chemicals to the atmosphere, simulate transport and fate of chemical substances, and develop measures of prevention and control, such as emergency preparedness and response. We are frequently called upon to investigate unusual atmospheric releases of chemicals, assess air pollution risks, simulate transport and fate of chemical substances, or develop measures of prevention and control, such as emergency preparedness and response. We have conducted air quality analyses in locations throughout the U.S. and internationally including desert, tropical, temperate, and arctic environments and have communicated our analytical results effectively to the general public, regulatory bodies, and in courts of law.

Exponent has worked on climate change and other global environmental compliance issues for more than 10 years. Our personnel include the lead author of one chapter in the Intergovernmental Panel on Climate Change’s Fourth Assessment Report, participants in state global climate change panels, and scientists who have testified before legislative bodies on global climate change.

Meteorological Modeling

Exponent meteorological modeling and analysis expertise includes meteorological modeling for air quality assessments, severe storm impacts including thunderstorms and hurricanes, real-time numerical meteorological and air quality forecasting, and model evaluation studies. Atmospheric scientists at Exponent have applied prognostic numerical meteorological models worldwide for many years at locations in North and South America, Europe, South Africa, Australia and New Zealand, the Middle East and the Far East. These mesoscale model studies include simulations in coastal and complex terrain environments in the tropics, mid-latitudes, and in the arctic. The models applied include the Weather Research and Forecasting (WRF) model, the Fifth Generation Mesoscale Meteorological (MM5) model, and the Air Pollution Model (TAPM) used in Australia. They have used methods to provide three-dimensional meteorological inputs for air quality models, forensic meteorological studies, and real-time forecasting applications. They have used these models to initialize local computational fluid dynamics (CFD) wind-loading simulations, and to provide wind forecasts for meteorologically sensitive activities.

Other stand-alone CFD modeling applications have included wind forces on buildings and offshore structures during hurricanes, design of wind fences to mitigate wind-blown fugitive dust, two-phase accidental releases of dense gases from railcars or vents, fogging and recirculation of exhausts from mechanical draft cooling towers, plume rise from air-cooled condensers, the effect of structures on wind turbines, and the contamination of fresh-air intakes by rooftop vent emissions.

Exponent atmospheric scientists have worked on numerous forensic meteorological studies using a variety of observational data including radar data, satellite imagery, wind profiler data, Doppler SODARS, NOAA three-dimensional numerical analysis data such as the Rapid Refresh analysis data (RAP) and the High-Resolution Rapid Refresh data (HRRR) to investigate complex wind patterns. We have worked on a study using RAP vertical cross sections to understand low level jets and associated boundary layer turbulence across the Texas Gulf coast and their impact of wind turbines. Exponent scientists have performed studies of thunderstorm induced dust storms over the southwestern United States using radar data. We have also used radar data to estimate rainfall amounts for flash flooding and landslide events in the absence of suitable rain gauge measurements. Radar data analysis also includes assessing severe thunderstorm impacts such as hail and downburst wind events. We used numerical meteorological modeling using the WRF model to develop vertical wind profiles in downbursts during severe convective storms. Additionally, we have performed several wind resource assessment studies, and air quality investigations for odor impacts and agricultural spraying impacts.

Our Team

Exponent’s unique atmospheric science assessment capabilities extend to aspects not found in traditional consulting firms. We can advise clients on broad, strategic issues related to air quality management and planning. Exponent’s Atmospheric Sciences staff has experience serving a wide range of private sector, industrial, and government clients around the world, including major companies operating aluminum facilities, oil refineries, chemical plants, electric generating stations, pulp and paper manufacturing, natural gas storage, and distribution, asphalt plants, mining facilities, agricultural activites, and renewable energy.

  • Clients benefit from our multidisciplinary approach, which includes the support of Exponent:
  • Chemical engineers
  • Combustion specialists
  • Building, structural, and civil engineers
  • Atmospheric scientists 
  • Thermal and process engineers
  • Risk assessors

Whether it is a simple or complicated problem, using standard or cutting-edge models, our approach is to solve problems efficiently.