Presentation prepared by Nasbah Ben



The Navajo Nation is the largest reservation in the United States and is home to over 250,000 tribal members. The reservation spans across Arizona, New Mexico, and Utah and is 27,000 square miles. The northeastern part of the reservation continues to be the sites of many power plants, generating stations, mining operations and natural gas wells. Although the presence of these large industrial sources of pollution exists, Navajo members still reside in the four corners region and therefore are most affected by the amount of pollution emissions in the area.

Currently ground level air monitoring data is being collected in the four-corners region. However, this data is not being submitted to the AirNow Data center, which allows access to ground level monitoring data on a national scale in real-time. Since Tribes have the authority to develop and implement their own air quality program, it would be beneficial to find an alternative to ground-level monitoring that would be cost effective and easy to interpret for tribes nation wide.

The main objectives of this project are to: examine the use of remote sensing as a tool to observe the distribution and transport of aerosols in the atmosphere above the four-corners region,examine the use of combined ground level PM monitoring with remotely sensed Aerosol Optical Depth (AOD) as a cost effective tools that tribes will be able to access, and to combine traditional knowledge with mainstream knowledge to create an effective tool for tribes to utilize.

Wind in the Navajo culture is seen as a source of life that affects movement, speech, and behavior of the people. On breathing, the powerful ones (Holy People) enter one’s lungs and are both a part of the breather as well as his being a part of and linked to all other beings. It is through the wind that all living beings are related. Each person has a wind that exists within, which provides the means for breathing, moving, thinking, and talking.

A Navajo told James McNeley (1981:35): “The whorls at the tips of our toes hold us to the Earth. Those at our fingertips hold us to the Sky. Because of these, we do not fall when we move about.” In the Navajo creation story, it is explained that wind was the source of life, exiting through our toes and fingers, through the whorls.

The four-corners regions is affected by a disproportionate amount of emission sources that affect the Indigenous communities in the region. Some areas are not monitoring for ground level air quality because of sensitive tribal issues, such as ceremonial burning. The correlation of Aerosol Optical Depth and ground level monitoring data may be a non-invasive way of collecting air quality data and keeping the public aware of air quality in the region.

Some benefits to using ground level data are that the data is uploaded hourly , pollutants can be speciated, it is becoming more prominent in tribal communities. Satellite data on the other hand has partial daily coverage, aerosols cannot be speciated, and clouds interfere with the data.

Correlating AOD and PM2.5 data is beneficial for forecasting, assessments, analysis, and observing air quality in the four-corners region. This data will be a useful tools for tribes on a national level since it has been shown to be cost-effective and easy to interpret.