Download Climate Change - School District of La Crosse

Climate Change
Questions
 Are global warming and climate change the same
thing?
 What is the difference between climate and
weather?
 What is the greenhouse effect?
 What is the most abundant greenhouse gas?
 Is climate change real?
 What evidence is there for climate change?
 Does the hole in the ozone layer cause climate
change?
What’s the Difference?
 Global Climate Change
– Any significant change in measures of climate
(temperature, precipitation or wind) lasting for an
extended period (decades or longer).
 Global Warming
– Average increase in the temperature of the atmosphere,
which can contribute to changes in global climate patterns.
Weather vs. Climate
 Weather
– Short-term (minutes to
months) changes in the
atmosphere
 Climate
– Long-term average
pattern of weather in a
particular area
– Typically use 30 years
of data
Greenhouse Gases
 Water Vapor: 0-4%
 Carbon Dioxide (CO2):
0.036%
 Methane (CH4):
0.00017%
 Nitrous Oxide (N2O):
0.00003%
 CFC’s
Greenhouse Effect
Earth’s average temperature would be 0 ºF without the greenhouse
effect compared to the average temperature of 60 ºF that we experience
Global Energy Budget
Evidence
Carbon Dioxide Levels in
Relation to Global Temperature
DEALING WITH GLOBAL
WARMING
 Climate change is such a difficult problem to
deal with because:
– The problem is global.
– The effects will last a long time.
– The problem is a long-term political issue.
– The harmful and beneficial impacts of climate
change are not spread evenly.
– Many actions that might reduce the threat are
controversial because they can impact
economies and lifestyles.
DEALING WITH GLOBAL
WARMING
 Two ways to deal with global warming:
– Mitigation that reduces greenhouse gas
emissions.
– Adaptation, where we recognize that some
warming is unavoidable and devise strategies to
reduce its harmful effects.
Solutions
Global Warming
Prevention
Cut fossil fuel use (especially
coal)
Shift from coal to
natural gas
Cleanup
Remove CO2 from smoke stack
and vehicle emissions
Store (sequester)
CO2 by planting trees
Improve energy efficiency
Shift to renewable energy
resources
Transfer energy efficiency and
renewable energy technologies
to developing countries
Reduce deforestation
Use more sustainable
agriculture and forestry
Limit urban sprawl
Reduce poverty
Sequester CO2 deep underground
Sequester CO2 in soil by using
no-till cultivation
and taking cropland out
of production
Sequester CO2 in the deep ocean
Repair leaky natural gas pipelines
and facilities
Use animal feeds that reduce CH4
emissions by belching cows
Slow population growth
Fig. 20-14, p. 481
DEALING WITH GLOBAL
WARMING
 Governments can tax greenhouse gas
emissions and energy use, increase
subsidies and tax breaks for saving energy,
and decrease subsidies and tax breaks for
fossil fuels.
 A crash program to slow and adapt to global
warming now is very likely to cost less than
waiting and having to deal with its harmful
effects later.
International Climate Negotiations:
The Kyoto Protocol
– Treaty on global warming which first phase went
into effect January, 2005 with 189 countries
participating.
– It requires 38 participating developed countries to
cut their emissions of CO2, CH4, and N2O to
5.2% below their 1990 levels by 2012.
– Developing countries were excluded.
 The U.S. did not sign, but California and Maine are
participating.
 U.S. did not sign because developing countries such
as China, India and Brazil were excluded.
Key Indicators





Sea Level
Carbon Dioxide Concentration
Global Surface Temperature
Artic Sea Ice
Land Ice
Evidence
 Sea Level Rise
– Global sea level rose 17 cm (6.7 in.) in the last century
– Rate in the last decade nearly double that of the last
century
 Global Temperature Rise
– Earth has warmed since 1880 with most of warming
occurring since the 1970s
– 20 warmest years occurred since 1981
– 10 warmest years occurred in the past 12 years.
Evidence
 Warming Oceans
– Top 700 m (2,300 ft) of ocean showing warming of
0.302 °F since 1969
 Shrinking Ice Sheets
– Greenland: lost 150-250 km3 (36-60 cubic miles) of ice
per year between 2002 and 2006
– Antarctica: lost 152 km3 (36 cubic miles) of ice between
2002 and 2005
Evidence
 Declining Arctic sea ice
– Extent and thickness of Arctic sea ice has declined
rapidly over last several decades
 Glacial retreat
– Retreating almost everywhere around the world
including Alps, Himalayas, Andes, Rockies, Alaska and
Africa
Evidence
 Extreme Events
– Number of record high temps increasing since 1950
– Number of record low temperature decreasing since
1950
– Increasing numbers of intense rainfall events
 Ocean Acidification
– CO2 content of oceans increasing since 1750
– Currently increasing 2 billion tons per year
– Increased ocean acidity by about 30%
NASA Interactives
 http://climate.nasa.gov/interactives/
IPCC
 Intergovernmental Panel on Climate Change
 Group of scientist from around the world that
review and assess information on climate
change
 Climate models and projections
Projections for North America
 Decreasing snowpack
in the western
mountains
 5-20% increase in
yields of rain-fed
agriculture in some
regions
 Increased frequency,
intensity and duration
of heat waves
Projections for Latin America
 Gradual replacement of tropical forest by
savannah in eastern Amazon
 Risk of significant biodiversity loss through species
extinction in many tropical areas
 Significant changes in water availability for human
consumption, agriculture and energy generation
Projections for Europe
 Increased risk of inland
flash floods
 More frequent coastal
flooding and erosion
 Glacial retreat in
mountainous areas
 Reduced snow cover and
winter tourism
 Extensive species losses
 Reductions of crop
productivity in S. Europe
Projections for Africa
 By 2020, 75-250 million
people are projected to be
exposed to increased
water stress
 Yields from rain-fed
agriculture could be
reduced by up to 50% in
some regions by 2020
 Agricultural production,
including access to food,
may be severely
compromised
Projections for Asia
 Freshwater availability projected to decrease by
2050
 Coastal areas at risk for increased flooding
 Death rate from disease associated with floods
and droughts expected to rise
Wisconsin’s Climate 1950-2006
 Average temperature increased 1.5 ºF
 Greatest amount of warming in winter and spring,
especially NW Wisconsin
 Nighttime lows warming faster than daytime highs,
especially in summer
 Decline in extremely cold winter nights, especially in NW
Wisconsin
 Date of last spring freeze occurring 6-20 days earlier
 Date of first fall freeze occurring 3-8 days later
 Growing season increased up to 4 weeks
 Annual average precipitation increased 15% although parts
of the N became drier
Wisconsin’s Future Climate
Projections
 4-9ºF increase by mid-21st Century
 Warming most pronounced in winter
 Fewer extremely cold winter nights and
more hot summer days
 Probability of greater than 3 in. rainstorms
will increase during spring and fall
Projected Change in the
Frequency of 90 ºF Days Per
Year from 1980 to 2055
Projected Change in the
Frequency of 2" Precipitation
Events (days/decade) from
1980 to 2055
Projected Change in Average
Winter Temp from 1980 to 2055
Projected Change in Annual
Temp from 1980 to 2055
Ice Cover on Madison Lakes
 http://climatewisconsin.org/story/ice-cover
Temperature Change
 http://climatewisconsin.org/story/temperatur
e-change
Shipping on the Great Lakes
 http://climatewisconsin.org/story/great-lakesshipping