Transcript human environment

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
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
Recent Earthquakes and
Volcanic Eruptions
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
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
Hydrologic Cycle
Precipitation Distribution
Google a map of the
Aral Sea
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 saltwater 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 selfsufficient 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 driedup 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
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
Muynak used
to be located
on the shores
of the Aral
Sea.
A centuries old way of life has
disappeared in just decades
Then and Now
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!
Shrinking of the Aral Sea
Animated
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 Atmosphere with
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
Natural Disaster Hot Spots
Natural Disaster Hot Spots
Locations of Visible Oil Slicks
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
Sources of Carbon Dioxide
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
Issues with Solving Environmental
Problems
Global conventions on environmental
problems
• Montreal Protocol- 1987 on CFC's
• Kyoto Protocol-1997 on Climate Change,
reduce Greenhouse gases
• US doesn't sign
Carbon Dioxide Emissions