Transcript Global Climate Change

Ecosystems and change
PART 2
Human impact on ecosystems
Loss of Biodiversity
• Biodiversity: the variety of plants, animals, and other living things
in a particular area or region
• Endangered Species Act of 1973 The purpose is to conserve
endangered and threatened species and the ecosystems on which
they depend as key components of America’s heritage.
• Endangered species: a species that is in danger of extinction
throughout all or a significant portion of its range.
• Threatened species: is one that is likely to become endangered in
the foreseeable future throughout all or a significant portion of its
range
• Reintroduction programs: animals raised or rehabilitated in a
accredited zoos or aquariums are released into their natural
habitats
• Protected Areas or conservation areas are locations which receive
protection because of their recognized natural, ecological and/or
cultural values.
Video The Endangered Species Act: 40 Years at the Forefront of Wildlife Conservation
(http://www.youtube.com/watch?v=DojGPBV4U0w) 4:37min
Video: Rescuing Endangered Species, CBS news, 4:22 - Phinda Game Reserve
(https://www.youtube.com/watch?v=rUmIU3Z4auc)
LOSS OF BIODIVERSITY
• What do you think is
the primary reason for
loss of biodiversity?
• HABITAT
DESTRUCTION
Deforestation
• Deforestation: when humans remove or clear large areas
of forest lands and related ecosystems for non-forest use.
These include clearing for farming purposes, ranching
and urban use. In these cases, trees are never re-planted
Effects of deforestation:
• Soil erosion (roots hold soil in
place)
•Loss of biodiversity due to loss of
habitat
•Climate change (trees remove
CO2; so fewer trees, more carbon
dioxide in the atmosphere)
Global Climate Change
Averaged over all land and
ocean surfaces,
temperatures warmed
roughly 1.53 degrees
Fahrenheit (rom 1880 to
2012, according to the
Intergovernmental Panel on
Climate Change
Scientific evidence for warming of the climate system is unequivocal."
-Intergovernmental Panel on Climate Change
-Video on UN study on causes of climate change:
http://www.today.com/video/today/53121189/#53121189 (2013 news report)
Greenhouse Effect
radiation from a planet's atmosphere warms the planet's
surface to a temperature above what it would be in the absence
of its atmosphere
Global Warming
• Global Climate Change - an increased effect
of greenhouse gases causing more heat to be
trapped by the Earth.
• http://www.epa.gov/climatechange/students/
basics/today/greenhouse-effect.html
• (more on what is the greenhouse effect)
Global Climate Change
This graph, based on the comparison of atmospheric samples contained in ice cores and
more recent direct measurements, provides evidence that atmospheric CO2 has increased
since the Industrial Revolution. (Source: NOAA)
Evidence for Global Climate Change
Video UN report 9/26/13 : http://climate.nasa.gov/evidence
1. Sea level rise Global sea level rose about 17 centimeters (6.7 inches) in the last century. The rate in
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the last decade, however, is nearly double that of the last century.4
Global temperature rise All three major global surface temperature reconstructions show that
Earth has warmed since 1880.5 Most of this warming has occurred since the 1970s, with the 20
warmest years having occurred since 1981 and with all 10 of the warmest years occurring in the past
12 years.6
Warming oceans The oceans have absorbed much of this increased heat, with the top 700 meters
(about 2,300 feet) of ocean showing warming of 0.302 degrees Fahrenheit since 1969.8
Shrinking ice sheets The Greenland and Antarctic ice sheets have decreased in mass. Data from
NASA's Gravity Recovery and Climate Experiment show Greenland lost 150 to 250 cubic kilometers
(36 to 60 cubic miles) of ice per year between 2002 and 2006, while Antarctica lost about 152 cubic
kilometers (36 cubic miles) of ice between 2002 and 2005
Declining Arctic sea ice Both the extent and thickness of Arctic sea ice has declined rapidly over
the last several decades
Glacial retreat Glaciers are retreating almost everywhere around the world — including in the
Alps, Himalayas, Andes, Rockies, Alaska and Africa.
Extreme events (The number of record high temperature events in the United States has been
increasing, while the number of record low temperature events has been decreasing, since 1950.
The U.S. has also witnessed increasing numbers of intense rainfall events)
Ocean acidification (Since the beginning of the Industrial Revolution, the acidity of surface ocean
waters has increased by about 30 percent)
ACID RAIN
any form of precipitation
with low pH
SO2 & Nox released from
burning of fossil fuels
mix with water vapor
in atmosphere
creating high levels of
nitric & sulfuric acids
Normal, clean rain has a pH value
of between 5.0 and 5.5, which is
slightly acidic. Typical acid rain has
a pH value of 4.0.
How Acid Rain Forms…
Causes of Acid Rain
• Human activities are the main cause of acid rain.
– Power plants release the majority of sulfur dioxide and nitrogen
oxides when they burn fossil fuels, such as coal, to produce electricity.
– The exhaust from cars, trucks, and buses releases nitrogen oxides and
sulfur dioxide into the air.
EPA: Acid Rain for Kids: http://www.epa.gov/acidrain/education/site_kids/lucy/1.htm
Effects of Acid Rain…
• Acid rain can harm forests
because it dissolves
nutrients the trees need.
(leaching)
• Trees that are located in
mountainous regions at
higher elevations, are at
greater risk because they
are exposed to acidic
clouds and fog, which
contain greater amounts
of acid than rain or snow.
Effects of Acid Rain…
• Reduced crop yields
• Acidic lakes/fish kills
• Damages monuments
Ozone Depletion
• Ozone = O3
• Forms bw stratosphere
& troposphere
• Filters harmful UV rays
before they reach
surface of Earth
• Ozone Depletion =
“hole” in ozone =
thinning of the ozone
layer
Thinning of the Ozone
Causes of Ozone Depletion: CFCs
CHLOROFLUOROCARBON
AIR POLLUTION
GROUND LEVEL OZONE
created by chemical
reactions between oxides of
nitrogen (NOx) and volatile
organic compounds (VOC) in
the presence of sunlight
GOOD UP HIGH
BAD NEARBY
Where does it come from?
• Emissions from
industrial facilities and
electric utilities, motor
vehicle exhaust,
gasoline vapors, and
chemical solvents are
some of the major
sources of NOx and VOC
What are VOC’s?
(volatile organic
compounds)
contains carbon and
that evaporates
(becomes a vapor) or
“off-gases” at room
temperature.
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Building Materials
Carpets and adhesives
Composite wood products
Paints
Sealing caulks
Solvents
Upholstery fabrics
Varnishes
Vinyl Floors
Home and Personal Care Products
Air fresheners
Air cleaners that produce ozone
Cleaning and disinfecting chemicals
Cosmetics
Fuel oil, gasoline
Moth balls
Vehicle exhaust running a car in an attached garage
Behaviors
Cooking
Dry cleaning
Hobbies
Newspapers
Non-electric space heaters
Photocopiers
Smoking
Stored paints and chemicals
Wood burning stoves
Volatile Organic Compounds (VOCs)
Difficulty breathing
shortness of breath
Coughing/ sore or scratchy
throat.
Inflame/ damage the airways.
Aggravate lung diseases such as
asthma, emphysema, and
chronic bronchitis.
Increase the frequency of
asthma attacks.
Make the lungs more susceptible
to infection.
Continue to damage the lungs
even when the symptoms have
disappeared.
WATER POLLUTION
contamination of water bodies (e.g. lakes, rivers, oceans, aquifers
and groundwater). This form of environmental degradation occurs
when pollutants are directly or indirectly discharged
into water bodies without adequate treatment to remove harmful
compounds.
What caused
Water
Pollution?
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SEWAGE
NUTRIENTS
WASTE WATER
CHEMICAL WASTE
PLASTICS
OIL
GROUND WATER CONTAMINATION
• occurs when man-made
products such as
gasoline, oil, road salts
and chemicals get into
the groundwater and ca
use it to become unsafe
and unfit for human
use.
SOURCES OF CONTAMINATION
GROUND WATER CONTAMINATION
LANDFILLS
FRACKING
HOG FARMS
What is Fracking?
• process of drilling and
injecting fluid into the
ground at a high
pressure in order to
fracture shale rocks to
release natural gas
inside.
• RISKS…ground water
contamination & earth
“tremors”
Click on photo to see an animation of
fracking
Hog Farms in NC
• Hog Farms are a major source of
jobs in NC. The waste from the
hogs is stored in lagoons. During
severe rain these lagoons have
overflowed and the waste enters
the local water
LANDFILLS
• carefully engineered
depression in the ground
(or built on top of the
ground, resembling a
football stadium) into
which wastes are put.
• Basically, a landfill is a
bathtub in the ground; a
double-lined landfill is
one bathtub inside
another. Bathtubs leak
two ways: out the bottom
or over the top.
TOXINS
Landfills create a toxic soup of
industrial and home-cleaning
chemicals; chemicals from
industrial solvents to household
cleaners accumulate and mix
over time.
LEACHATE
When landfill waste degrades
and rain rinses the resulting
products out, leachate is formed.
The black liquid contains organic
and inorganic chemicals, heavy
metals as well as pathogens; it
can pollute the groundwater and
therefore represents a health risk
GREENHOUSE GASES
the methane produced by the
rotting organic matter in
unmanaged landfills is 20 times
more effective than carbon
dioxide at trapping heat from the
sun.
CONCERNS REGARDING
LANDFILLS
These risks, along with the odor and unsightliness of
landfills are the reasons for many heated debates about
where landfills should be built…BUT…as the world
population increases…there will continue to be an
increase in solid waste…and it has to be disposed of
somewhere!
EUTROPHICATION
• Watch animation
• video 2
• video 3
• Increase in nutrients in aquatic ecosystems
• Result in increase in plant growth (particularly
phytoplankton)
• Leads to algal blooms
• may be toxic…may change oxygen levels
• Increase in bacteria…use up the oxygen
• Higher aquatic life dies
Human Impacts on Ecosystems in North Carolina
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Pfiesteria is a microscopic
organisms that sometimes behave
like plants and sometimes like
animals.
Process of pfiesteria growth:
•Animal waste or fertilizers
with nutrients enter the water
• The nutrients in the waste
cause lots of algae to grow.
Which increases the amount
of Pfiesteria .
•Pfiesteria produces toxins
that cause lesions in fish and
have caused fish kills in the
lower Neuse, Tar-Pamlico, and
New River estuaries of North
Carolina
http://www.youtube.com/watch?v=IAFVC1T0KpU - show first minute
Pesticide Use
• Pesticides are chemicals used to eliminate or control a
variety of agricultural pests that can damage crops and
livestock and reduce farm productivity
• Insecticides (bug killers), herbicides (weed killers),
rodenticides (rodents), fungicides (fungus killers)
• designed to attack an insect's brain and nervous
system, which can mean they have neurotoxic effects
in humans as well.
• ongoing, low-level exposures can increase the risk of
diseases or disorders such as cancer, Parkinson’s
disease or infertility and other reproductive harms.
Impacts of Pesticide Use…
• Loss of biodiversity; especially key species
like bees
• Water pollution
• Soil contamination
• Pest resistance, resulting in
the need for increased application of
pesticides
• Human health issues
Pesticide Use
Biomagnification –
• higher concentrations of
a particular chemical,
such as the pesticide
DDT, are reached in
organisms higher up the
food chain, generally
through a series of preypredator relationships
• Examples: DDT and the
bald eagle; PCBs and
Lake Crabtree
• Video on DDT and bald
eagle:
http://www.youtube.co
m/watch?v=R7M02vNhz
wE
Human Impacts on Ecosystems in North Carolina
• Coastal Erosion: a natural
process along the world’s
coastlines that occurs
through the actions of
currents and waves and
results in the loss of
sediment in some places
and accumulation in others.
This movement of sand is
called longshore drift.
While longshore drift ensures the long-term stability of the
coast, it also makes the beach an unpredictable place to
build houses.
Human Impacts on Ecosystems in North Carolina
Solutions to Coastal Erosion????
One solution that has been enacted is the construction of hard
structures like jetties, groins, and sea walls designed to hold
beach sand in place.
• While hard structures can
protect beach homes and other
buildings threatened by
erosion, they’ve been criticized
for causing increased erosion
further down the beach.