ABOUT INVASIVE SPECIES: Invasive species is the term for animals and plants that are new to an environment. This can happen by migration, the wind, or when people travel from one area to another. It could be a burr that catches on a shoelace, or a mussel carried by a boat on a long voyage. When invasive species take hold in a new location, they can disrupt the existing food chain and, in some cases, crowd out organisms that had long been established in an environment, complicating an entire ecosystem.

ABOUT OZONE: Ozone is a rare element in our atmosphere; there are about three molecules of ozone per every 10 million air molecules, and yet it plays a vital role in human health. Most ozone (90%) can be found in an upper layer of the earth's atmosphere called the stratosphere. It is beneficial because it absorbs most of the damaging ultraviolet sunlight, which can cause skin cancers, among other conditions. The remaining 10% of ozone can be found in a lower region called the troposphere. Here, it reacts with other molecules to produce smog, which has toxic effects on crops, forest growth, and human health.
SMOG MAKES BREATHING DIFFICULT: Smog can make breathing difficult and can make human beings more susceptible to cardio-respiratory diseases. People already suffering from heart or lung disease are particularly affected. The two main ingredients in smog that affect human health are ground-level ozone and fine airborne particles.
The American Meteorological Society and the American Geophysical Union contributed to the information contained in the TV portion of this report.
