Physical Geography

Week 4

Atmospheric Pollutants

• Burning of Biomass + Organic materials

• Harmful to humans + environment

Anthropogenic Pollution

Created by People

• Most prevalent in Urban regions

• Significant effects on health

  • Contributes to roughly 1.3 million deaths

Photochemical Smog

Low Level Ozone

• Interacts with sunlight to create a haze

• Derived from NOs and volatile organic compounds reacting with the air

• Warms local atmosphere,

Industrial Smog

Derived from Coal Burning

• Sulphur oxides form sulphur trioxide in the air

• Forms sulphate aerosols and sulphuric acid (acid rain)

• Results in low-pH water bodies

Particulates and Aerosols

Fine Liquid + Solid particles like

• Haze

• Smoke

• Dust

• Black carbon (produced from dung burning) (travels far and can end up in the Arctic, affecting albedo of snow)

Affects human health

• Small particulates of aerosols can enter lungs and bloodstream if small enough

Timeline of Air Pollution

• Post WWII

  • Mass suburbanization, increased reliance on cars

• Silent Spring, 1969

  • Concern raised over mass use of DDT for Dutch Elm Disease, which caused mass ecosystem disturbances and human fatalities

• President Kennedy, 1969, Environmental Policy Act

• Photographing Earth from Space

Timeline of Air Pollution (Continued)

• 1970, Environmental Protection Agency

  • Protects environment from industry, governmental pressures

• 1970, Clean Air Act

  • Limited use of some pollutants

  • Outright ban on other pollutants

  • Taxes imposed on some pollutants

Natural Sources of Pollutants

• Volcanos

• Forest Fires

• Plants (pollens, hydrocarbons)

• Decaying plants

• Soil (dust, viruses)

• Ocean (salt spray)