Ecology & Environmental Problems

Dr. Ron Chesser

Water, Rain, Acid Rain

Chapter 26

Too Much WaterIn the United States, the average annual cost of flood damage is more than $2 billion. Each year about 100 people lose their lives to floods.

El Niño

Floods and Flood Plain

Flood Control

Runoff

• Meteorological factors affecting runoff:• Type of precipitation (rain, snow, sleet, etc.)

Rainfall intensity Rainfall amount Rainfall duration Distribution of rainfall over the drainage basin Direction of storm movement Antecedent precipitation and resulting soil moisture Other meteorological and climatic conditions that affect evapotranspiration, such as temperature, wind, relative humidity, and season.

Runoff

• Physical characteristics affecting runoff:• Land use

Vegetation Soil type Drainage area Basin shape Elevation Slope Topography Direction of orientation

• Drainage network patterns Ponds, lakes, reservoirs, sinks, etc. in the basin, which prevent or alter runoff from continuing downstream.

Rain

• 1 inch of rain falling on 1 acre

is equal to about 27,154 gallons of water.

20 inches per year 543,080 gallons

Amount of water received when an inch of rain occurs

CityArea(square miles)

Amount of water(million gallons)

Atlanta, GA 131.7 2,289

Baltimore, MD 80.8 1,404

Chicago, IL 227.1 3,947

Cincinnati, OH 78.0 1,356

Denver, CO 153.4 2,666

Detroit, MI 138.8 2,412

Honolulu, HI 85.7 1,489

Houston, TX 579.4 10,069

Jacksonville, FL 757.7 13,168

Louisville, KY 62.1 1,079

Milwaukee, WI 96.1 1,670

New Orleans, LA 180.6 3,139

New York, NY 303.3 5,271

Philadelphia, PA 135.1 2,348

Salt Lake City, UT 109.1 1,906

Seattle, WA 83.9 1,458

Washington, DC 61.4 1,067

Ecology & Environmental Problems

Dr. Ron Chesser

Reading: Chapter 26

Air Pollution and Acid Rain

Acid Rain – What is it?

• Scientists have confirmed, that sulfur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain. In the US, About 2/3 of all SO2 and 1/4 of all NOx comes from electric power generation that relies on burning fossil fuels like coal.

• Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic compounds. Sunlight increases the rate of most of these reactions.

• The result is a mild solution of sulfuric acid and nitric acid.

Acid Rain

• “Acid rain" is a broad term used to describe several ways that acids fall out of the atmosphere. A more precise term is acid deposition, which has two parts: wet and dry.

Acid Rain – Wet Deposition

• Wet deposition refers to acidic rain, fog, and snow. As this acidic water flows over and through the ground, it affects a variety of plants and animals.

• The strength of the effects depend on many factors, including how acidic the water is, the chemistry and buffering capacity of the soils involved, and the types of fish, trees, and other living things that rely on the water.

Air Pollution and Acid Rain

Acid Rain – Dry Deposition

• Dry deposition refers to acidic gases and particles. About half of the acidity in the atmosphere falls back to earth through dry deposition. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees.

• Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. When that happens, the runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone.

How Do We Measure Acid Rain?

• Acid rain is measured using a scale called "pH." The lower a substance's pH, the more acidic it is. See the pH page for more information.

• Pure water has a pH of 7.0. Normal rain is slightly acidic because carbon dioxide dissolves into it, so it has a pH of about 5.5.

• As of the year 2000, the most acidic rain falling in the US has a pH of about 4.3.

Air Pollution

• One type of air pollution is the release of particles into the air from burning fuel for energy. Diesel smoke is a good example of this particulate matter . The particles are very small pieces of matter measuring about 2.5 microns or about .0001 inches. This type of pollution is sometimes referred to as "black carbon" pollution. The exhaust from burning fuels in automobiles, homes, and industries is a major source of pollution in the air.

Air Pollution

• Another type of pollution is the release of noxious gases, such as sulfur dioxide, carbon monoxide, nitrogen oxides, and chemical vapors. These can take part in further chemical reactions once they are in the atmosphere, forming smog and acid rain.

Air Pollution

• Pollution also needs to be considered inside our homes, offices, and schools. Some of these pollutants can be created by indoor activities such as smoking and cooking. In the United States, we spend about 80-90% of our time inside buildings, and so our exposure to harmful indoor pollutants can be serious. It is therefore important to consider both indoor and outdoor air pollution.

Black Carbon Pollution

• Black carbon pollution is the release of tiny particles into the air from burning fuel for energy. Air pollution caused by such particulates has been a major problem since the beginning of the industrial revolution and the development of the internal combustion engine . Scientific publications dealing with the analysis of soot and smoke date back as early as 1896.

Noxious Gas Air Pollution

• Another type of pollution is the release of noxious gases, such as sulfur dioxide, carbon monoxide, nitrogen oxides, and chemical vapors.

Health Effects of Air Pollution

• Examples of short-term effects include irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis and pneumonia. Other symptoms can include headaches, nausea, and allergic reactions. Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema. In the great "Smog Disaster" in London in 1952, four thousand people died in a few days due to the high concentrations of pollution.

Health Effects of Air Pollution

• Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys. Continual exposure to air pollution affects the lungs of growing children and may aggravate or complicate medical conditions in the elderly. It is estimated that half a million people die prematurely every year in the United States as a result of smoking cigarettes.

Air Pollution and Health Costs

• Research into the health effects of air pollution is ongoing. Medical conditions arising from air pollution can be very expensive. Healthcare costs, lost productivity in the workplace, and human welfare impacts cost billions of dollars each year.

Air Pollution and Acid Rain