Our air and precipitation monitoring allows us to understand the dynamics pollution produced in industrial processes, especially pollution from the burning of fossil fuels such as coal and gasoline. Our program includes several methods that cover a broad range of pollutants. We collect precipitation chemistry data using a Yankee Environmental Systems collector, which uses a sensor that causes a cover to open, revealing a clean bucket when precipitation occurs and closes when the precipitation ceases. The instrument collects all kinds of precipitation including snow and ice as well a rain. Samples are collected after every event and analyzed at the Cary Institute for pH and a suite of other constituents that are important for understanding acid deposition.
Our air quality is monitored via a system similar to that used by the Clean Air Status and Trends Network (CASTNET). We collect air samples via low-volume filter packs, which allow us to monitor particles and gases that are important components of acid deposition. We also monitor ammonia concentration as part of the National Atmospheric Deposition Program (NADP), Ammonia Monitoring Network. In addition, we monitor ground-level ozone, a key component of smog, in partnership with the New York State Department of Conservation.
For access to data go to Archived Data and Data Summaries.
Good Ozone, Bad Ozone
Ground-level ozone is bad, but we need ozone in our upper atmosphere where it blocks ultraviolet (UV) radiation. We monitor upper atmosphere ozone by monitoring UV radiation. At ground-level, ozone is produced from precursors emitted by motor vehicles and other pollution sources. Because sunlight and temperature are needed for the formation of ozone, it is primarily a summertime pollutant. The New York State DEC monitors ozone continuously at the Cary Institute. You can get real-time ozone information from the AIRNOW website. For more about ozone, visit the DEC website.
Acid rain forms from sulfur dioxide (SO2) that is emitted largely by coal-burning power plants. In the atmosphere, the SO2 transforms to sulfate, which combines with hydrogen ions to form sulfuric acid. There are other forms of acidity in our rain, but sulfuric acid is dominant here at the Cary Institute. The Clean Air Act is a federal law that has provisions to control acid rain. It does so by regulating how much SO2 coal-burning power plants and other polluters can emit. Since the acid rain provisions of the law were enacted, acidity and sulfate in precipitation have declined in the United States. Even with this very important regulation, the acidity of our pollution today is well above that of unpolluted or normal precipitation.
The effects of acid rain are not only from the concentration of acidity and its associated ions, but also from the total amount of those constituents that has fallen on the landscape. That total amount is often referred to as ‘deposition’, or the amount in mass per unit area that is deposited on the land. These constituents can be deposited in the form of dry particles or vapor, which is called dry deposition, and they can be dissolved in precipitation (rain, snow, sleet etc.), which is called wet deposition. The two most important components are Sulfur (S) and Nitrogen (N). They concern ecologists because they can fundamentally change the biology and chemistry of an ecosystem, often in harmful ways.
The Cary Institute participates in the The NADP Ammonia Monitoring Network, a national program consisting of many sites throughout the United States where ammonia in the air is monitored via passive samplers that are exchanged every two weeks. These samplers are simple tubes coated with a weak acid solution, which reacts with ammonia, a weak base. The ammonia adheres to the surface of the tube which can be analyzed to determine the total concentration of ammonia in the air during each two week deployment period. This program allows us to understand a critical nitrogen component that is important not only in eutrophication of natural systems but is also a precursor to particulate pollution, which can exacerbate asthma and other respiratory problems.
Our dependence on power plants and automobiles has increased CO2 emissions at an alarming rate. Worldwide, the loss of natural vegetation caused by deforestation further adds to atmospheric CO2. The effect of increasing CO2 concentration in our air will continue to be devastating unless we act to curb it. The Cary Institute monitors CO2 to provide a better understanding of fine scale CO2 dynamics. Our CO2 monitor makes instantaneous CO2 measurements every 2 seconds. These two second readings are averaged every three minutes together with wind speed and direction measurements. Together these measurements allow us to understand the affects of wind direction and speed as well as time of year and time of day on CO2 dynamics.