Navigation at Sea, History of. The first Western civilization known to have developed the art of navigation at sea were the Phoenicians, about 4,000 years ago (c. 2000 B.C.E. ). Phoenician sailors accomplished navigation by using primitive charts and observations of the Sun and stars to determine directions.
Air pollution risk is a function of the hazard of the pollutant and the exposure to that pollutant. Air pollution exposure can be expressed for an individual, for certain groups (e.g. neighborhoods or children living in a county), or for entire populations.ther examples include carbon monoxide gas from motor vehicle exhaust, or the sulfur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact.
The term smog was first used in London during the early 1900's to describe the combination of smoke and fog. What we typically call smog today is a mixture of pollutants but is primarily made up of ground-level ozone.Ozone can be beneficial or harmful depending on its location.mog is a visible example of air pollution. You can look at the horizon during the day to see how much haze there is in the air. In addition, most cities measure the concentrations of pollutants in the air and report the results to the public.