KEY CONCEPT Fossil fuel emissions affect the biosphere.

Pollutants accumulate in the air. Pollution is any undesirable factor added to the air, water, or soil. Smog is one type of air pollution. sunlight interacts with pollutants in the air pollutants produced by fossil fuel emissions made of particulates and ground-level ozone (O3) Smog can be bad for human health Ozone in the Ozonosphere (ozone layer) protects us from UV radiation Hole in the ozone?

Particulates – microscopic bits of dust, metal, and unburned fuel, 1-10 microns in size. Can lead to problems with asthma, lung cancer, and other breathing problems.

Fine particulate matter (PM2. 5), are 2 Fine particulate matter (PM2.5), are 2.5 micrometers or less in diameter, about a tenth the fraction of human hair. These small particles can get past the body’s normal defenses and penetrate deep into the lungs. The map shows very high levels of PM2.5 in a broad swath stretching from the Saharan Desert in Northern Africa to Eastern Asia. When compared with maps of population density, it suggests more than 80 percent of the world's population breathe polluted air that exceeds the World Health Organization's recommended level of 10 micrograms per cubic meter.

Acid rain is caused by fossil fuel emissions. produced when pollutants in the water cycle cause rain pH to drop (Nitrogen and sulfur oxides) creates Nitric and Sulfuric acids can lower the pH of a lake or stream can harm trees, amphibians, buildings Normal rain – pH 5.6 Is this acidic or alkaline?

Air pollution is changing Earth’s biosphere. The levels of atmospheric carbon dioxide rise and fall over time. High levels of carbon dioxide are typical of Earth’s warmer periods.

sunlight penetrates Earth’s atmosphere The greenhouse effect slows the release of energy from Earth’s atmosphere. sunlight penetrates Earth’s atmosphere energy is absorbed and reradiated as heat (infrared) greenhouse gases absorb longer wavelengths Greenhouse gas molecules (CO2, CH4, H2O) absorb energy reradiated by Earth’s surface and slow the release of the energy from the Earth’s atmosphere. methane (CH4) water (H2O) carbon dioxide (CO2)

Global warming refers to the trend of increasing global temperatures. Over last 100 years, average global temperature has increased 1.2o F. By 2100, could increase anywhere from 2.2 to 10o F. North Pole