Both governments report significant progress protecting the environment and public health by reducing emissions that cause acid rain and contribute to cross-border air pollution. However, the report also shows increasing nitrate concentrations in many lakes and streams in the Adirondack and Catskill Mountains of New York, the mid-Appalachian region of the United States, Ontario and Quebec.
Nitrates come from acid rain in the atmosphere.
The report also discusses the harmful effects of sulfur compounds on buildings and on visibility in U.S. national parks. Both countries are in the process of conducting studies on the need for and consequences of further emission reductions to protect sensitive ecosystems. The U.S. study was mandated under the 1990 Clean Air Act Amendments. Additionally, the report addresses new inroads in scientific and technical cooperation between the two countries, as well as emission inventories and data trends from 1980 to 2010, and atmospheric modeling, monitoring and pollution control technologies. The Progress Report was a cooperative effort between the governments of the United States and Canada.