The atmosphere of present-day Earth
Ammonia is not currently a regulated pollutant in the United States. While some filed measurements exist, they are sparse and lead to the lack of understanding of the atmospheric nitrogen cycle especially in regions with high ammonia concentrations. One of the largest sources of ammonia emissions is agriculture through livestock manure and crop fertilizers. Nitrogen can redopsit from the air to the ground through wet and dry processes. However, nitrogen deposition can be very harmful to not only terrestrial ecosystems, but also coastal ecosystems by creating "dead zones" downstream from sources of nitrogen. Furthermore, ammonia also affects air quality. It can react with both ambient sulfuric and nitric acids to create fine particles that can lead to visibility degradation along with having adverse impacts of human health.
There are different types of fog and the type is dependent on its formation mechanism. Two types of fog will be focused on for this portion of the project. First, radiation fog occurs during clear and calm conditions when Earth's surface cools, radiating heat upward into space, cooling the air above ground. Once that air has cooled enough to cause 100% humidity, a radiation fog can form. These fogs occur frequently in northern Iowa during the winter months. Second, evaporation fog occurs in late fall when cool air passes over warm bodies of water. The process of cooling the warm water above the water surface results in localized fogs forming near their parent body of water.
During the process of fog formation, aerosol particles can mix with water vapor to create fog droplets. Fogs are important processors of ambient aerosols and soluble trace gases, like ammonia. Ambient ammonia can easily be taken up by fog droplets and, while they can be released back into the air when fog dissipates, it also can be removed from the air through wet deposition processes. As a result, ammonia can directly enter the watershed since fog often occurs near rivers or other bodies of water.
This aspect of the project will focus on investigating how reduced nitrogen interacts with fog in northern Iowa, particularly in the Cedar Valley region. This will improve current understanding of the biogeochemical cycle of nitrogen in today's atmosphere. The Cedar Valley region is ideal for this study and fog collection as Iowa has very high concentrations of ammonia in the air as a result of the prevalence of agriculture in the area. Furthermore, UNI is nearby the Cedar River watershed and George Wyth State Park to study both radiation and evaporation fogs in agriculture based areas on the Cedar River. This portion of the project will provide insight the effects agriculture has on Iowa's watershed through the atmosphere.
There are different types of fog and the type is dependent on its formation mechanism. Two types of fog will be focused on for this portion of the project. First, radiation fog occurs during clear and calm conditions when Earth's surface cools, radiating heat upward into space, cooling the air above ground. Once that air has cooled enough to cause 100% humidity, a radiation fog can form. These fogs occur frequently in northern Iowa during the winter months. Second, evaporation fog occurs in late fall when cool air passes over warm bodies of water. The process of cooling the warm water above the water surface results in localized fogs forming near their parent body of water.
During the process of fog formation, aerosol particles can mix with water vapor to create fog droplets. Fogs are important processors of ambient aerosols and soluble trace gases, like ammonia. Ambient ammonia can easily be taken up by fog droplets and, while they can be released back into the air when fog dissipates, it also can be removed from the air through wet deposition processes. As a result, ammonia can directly enter the watershed since fog often occurs near rivers or other bodies of water.
This aspect of the project will focus on investigating how reduced nitrogen interacts with fog in northern Iowa, particularly in the Cedar Valley region. This will improve current understanding of the biogeochemical cycle of nitrogen in today's atmosphere. The Cedar Valley region is ideal for this study and fog collection as Iowa has very high concentrations of ammonia in the air as a result of the prevalence of agriculture in the area. Furthermore, UNI is nearby the Cedar River watershed and George Wyth State Park to study both radiation and evaporation fogs in agriculture based areas on the Cedar River. This portion of the project will provide insight the effects agriculture has on Iowa's watershed through the atmosphere.