TRACE-P Mission

This example is derived from an atmospheric field study performed by NASA as part of the Global Tropospheric Experiment. The TRACE-P mission studied the outflow and evolution of pollution from the Asian continent. During the mission, NASA’s DC-8 and P3-B research aircraft were flown in the study region to measure atmospheric pollutants. vGeo was used for flight planning and data analysis in support of this mission. This use illustrates the utility of merging many different data sets – atmospheric model forecasts, in situ measurements from aircraft, ground station and weather balloon measurements, satellite data, and more – into a single virtual world. This data fusion capability allows scientists to analyze how the various data sets compare, contrast, and complement each other.

In all, over 10 GB and 60,000 files of data were collected or simulated during the mission. vGeo managed this data as separate “worlds”, each with a separate focus and visualizing about 1-2 GB of data. For example, one world focused on a particular outflow event associated with the offshore movement of a cold front. Visualizations of wind vectors, isosurfaces of cloud parameters, and other data from atmospheric forecasts helped to identify the front. Next, isosurfaces of forecast chemical pollutants showed plumes of aerosols trapped behind the front as it moved offshore. Weather satellite images confirmed the position of the front and the associated cloud structure. Perhaps most importantly, visualizations of in situ measurements from instruments onboard the research aircraft showed strong correlations between the forecast data and the actual measurements collected as the aircraft flew along and across the front. Later, visualizations of remotely sensed data from satellites were added to the world and showed very good agreement with in situ measurements and forecasts. Other ancillary data, such as fire counts and ground station air quality measurements, were brought in to illustrate likely sources of the pollution.

TRACE-P Mission Data Details

The list below summarizes the various data sets collected and visualized during the mission:

• Atmospheric model forecasts, regional/global scale (6 GB)
• Pollutants (aerosols, CO, O3, SO4, etc)
• Wind fields
• Cloud parameters
• Dust
• Air parcel trajectories (3 GB)
• Aircraft LIDAR measurements (remote sensing by laser)
• In-situ aircraft measurements - over 200 chemical species (130 MB)
• Satellite images (330 MB)
• Satellite data, atm. chemistry measurements (1 GB)
• Ground station air quality measurements
• Ozonesondes (weather balloons)
• Radar measurements (FTIR)
• Fire counts/positions
• Texture maps (land cover, vegetation, overlaid on topography)
• Topographic data