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HUMAN ENVIRONMENT by Parisa Watson. Chapter 13. Field NOTE. -Tsunami-Dec 26, 2004 Sri Lanka Sumatra -CFC's-chlorofluorocarbons-growing hole in the ozone layer in Antarctica -Industrial Production in Netherlands in Germany causing acid rain in Scandinavia.
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HUMAN ENVIRONMENTby Parisa Watson Chapter 13
Field NOTE -Tsunami-Dec 26, 2004 Sri Lanka Sumatra -CFC's-chlorofluorocarbons-growing hole in the ozone layer in Antarctica -Industrial Production in Netherlands in Germany causing acid rain in Scandinavia
How Has the Earth Environment Changed over Time? Alfred Wegener-Continental Drift Theory Pangea-Supercontinent
-humans have a powerful impact on the environment -Earth 70% Water -Volcanic Eruptions cause mass depletions and contribute to mass extinctions -Pacific Ring of Fire
Plate Tectonics Division of the Earth’s crust into plates, which are in motion
Glaciations • Pleistocene (less than 2 million years ago) marked by • Glaciations: Permanent ice stable and growing • Interglaciation: Warming spell in which ice recedes • Emergence of humans (homo sapiens) during interglacial between 120,000 and 100,000 years ago • Most recent glaciation: Wisconsin Glaciation
Recent Glacial History • Holocene: Interglaciation that began 18,000 years ago. • Little Ice Age • A minor glaciation that began in the early 1300s • Growing glaciers • Effects on agricultural production • Abandonment of Greenland and Iceland by Europeans • Abandonment of Chung Ho’s voyages • Black Death (bubonic plague)
Warming Phase • Eruption of Tambora (1815) on Sumatra (Indonesia) • Local pollution of land and water by ash and acid • Ash and dust in atmosphere • Cooling of temperatures worldwide: “Year without summer” (1816) • Food shortages • Warming since about 1850
How Have Humans Impacted Earth’s Environment? • Altering ecosystems • All humans (over time) altering environments • Impact greater with growth in population • Environmental stress • Cutting forests, emitting pollutants, spilling oil • Burying toxic waste, dumping garbage in oceans
Water • A renewable resource (replenished as used) • Water shortages: Depletion of water in aquifers (porous, water-holding rocks) at a rapid rate • Causes of shortages • Growing population • Large population concentrations near small supplies • Agricultural and industrial use • Where are shortages in the US? • People still cluster around rivers
Las Vegas and Lake Mead http://earthengine.google.org/#intro
Golf Courses and Water! Go Green! http://www.npr.org/templates/story/story.php?storyId=91363837
The Dying Aral Sea Effects of climatic cycles and human interference -Kazakhstan/Uzbekistan -irrigation, pesticide use -lost 3/4 surface area
The Aral is an inland salt-water sea with no outlet. It is fed by two rivers, the Amu Darya and Syr Darya. The fresh water from these two rivers held the Aral's water and salt levels in perfect balance. • In the early 1960's, the Soviet central government decided to make the Soviet Union self-sufficient in cotton and increase rice production. Government officials ordered the additional amount of needed water to irrigate these fields be taken from the two rivers that feed the Aral Sea.
Large dams were built across both rivers, and an 850-mile central canal with a far-reaching system of "feeder" canals was created. When the irrigation system was completed, millions of acres along both sides of the main canal were flooded and the water flow was decreased dramatically.
It was not until after the construction of the irrigation ditches were completed that problems began to occur. With the loss of the water flow to the Aral Sea, the water level began to drop. The water level has dropped by 16 meters (40 feet) and the volume has been reduced by 75 percent, a loss equivalent to the water in both Lakes Erie and Huron.
SO MUCH SALT … • Over the next 30 years, the Aral Sea experienced a severe drop in water level, its shoreline receded, and its salt content increased. The salt content of the lake is now three times what it is in the ocean.
Fishing Industry Dies… Because there was too much salt in the water it began killing the plants and animals. All 20 species of fish that once lived in the Sea are now extinct. As the marine life died, the fishing industry suffered. The once thriving fishing industry employing roughly 60,000 people in the early 1960s has been destroyed. Old fishing boats in dried lake bed.
Effects on Climate • Due to the recession of the Aral Sea, the climate has changed ... • Lakes and seas tend to have a moderating effect on the climate. In other words, the land right next to a body of water tends to be warmer in the winter and cooler in the summer than land that's not near the water. As the Aral Sea has lost water, the climate has become more extreme Winters have become harsher and longer. Summers hotter and shorter.
Poisonous Effects … • The farms in the area use some highly toxic pesticides and other harmful chemicals. For decades, these chemicals contaminated the river water that once led to the Aral Sea. • When the wind blows across the dried-up sea bed, it carries dust containing these toxic chemicals resulting in poor drinking water and pollution of the earth.
Effects on the People • Drinking water supplies have dwindled, and the water is contaminated with pesticides and other agricultural chemicals as well as bacteria and viruses. • People have become poorer and cannot afford healthy food, they grow weak and therefore easy victims to diseases such as tuberculosis. Other health problems like anemia, heart problems and respiratory diseases are rampant
Salt and Dust in the air… • An effect of the reduction in the Aral Sea’s size is the exposure of the lake bed. Today, strong winds blow the exposed land picking up and depositing tens of thousands of tons soil every year. • This process has contributed to significant reduction in breathable air quality for nearby residents • It has also affected crop yields due to those heavily salt-laden particles falling on arable land.
The vast area of exposed seabed is laced with pesticides, so when the wind blows, dust storms spread salt and toxic substances over hundreds, if not thousands of kilometers. It's estimated that 75 million tons of toxic dust and salts are spread across Central Asia each year. If the Aral Sea dries up completely, 15 billion tons of salt will be left behind.
A City that Once Was Muynak was once a fishing port the boasting a proud fishing fleet during the Soviet era. • Today, Muynak is a desert town more than a hundred kilometers (62 miles) from the sea. • The only reminders of the once thriving fishing activity are the rusting hulks of ships and an ancient fish plant. • The ecological effect has been disastrous and the economic, social, and medical problems for people in the region catastrophic to their way of life. Muynak used to be located on the shores of the Aral Sea.
The shrinking of the Aral Sea has been called “one of the planet’s worst environmental disasters”.
In 1960, the Aral Sea was the world’s 4th largest lake. The sea is now only 10% of it’s original size!
Water Waste Overuse of Water by people
Water and Israeli-Palestinian Relations • Israel’s major water resources • Jordan River • Aquifer under West Bank • 30 percent of flow to Sea of Galilee from Golan Heights
Now she's back in the Atmospherewith drops of Jupiter in her hair...air air airr... • A thin layer of air lying directly above the lands and oceans • Natural impacts (volcanic eruptions) • Human impacts • Global warming-2-4 degrees over next 50 years • disappearance of islands • Acid rain • forms when sulfur dioxide/nitrogen oxides are released into the atmosphere by the burning of fossil fuels • can harm the ecosystems, killing fish, loss of crops, corrosion of buildings
The Land • Deforestation-clearing of the forest: Effect on oxygen cycle- • could be no more rainforest in 90 yrs. at this rate • US-2nd growth trees-issues? • demand for low-cost hamburgers has led to cutting down of trees to make way for cattle herds • Soil erosion: Soil not having enough time to rebound • "quiet crisis"-pressure on farmers to produce more, can't leave land unused
The Eyes of Nye: Global Climate Change: Earth's Atmosphere Heats Up
Waste Disposal • Waste disposal • Solid waste filling sanitary landfills -LDC's-open dumps -MDC's-sanitary landfills -some export waste to LDC's -landfill capacity in many states, have to buy space from other states • Problem of disposal and confinement of toxic and radioactive wastes -
Biodiversity • Loss of biodiversity because species are threatened or quite concentrated • Species with a small range most impacted • species becoming extinct
What Are the Major Factors Contributing to Environmental Change Today? Political ecology • An approach to nature-society relations • Relationship of humans w environment
Major Factors Contributing to Environmental Change • Population • Technology: Resource extraction to fuel technologies • Transportation • Significant pollution • Energy demands—oil • Patterns of Consumption • core-greater demands on Earth's resources
Improvements in the technology of transportation over time have required more energy 1) by foot or boat 2)Domesticated animals 3)sail boats 4) steam engine 5) combustion engine Todays transportation causes more pollution than ever before
How Are Humans Responding to Environmental Change? • Environmental problems not confined to states • Laws that affect change passed by state • Air pollution drifting across borders
States vs. Environmental Issues • Major forest regions of Africa not along state boundaries • World Bank’s planning regions drawn along state boundaries