Environmental Science 101 Chapter 13 Climate Change

Long term changes in the earth’s average temperature, precipitation and other environmental factors. 2,500 scientists 29,000 sets data Rapid Change Human Activity Fossil Fuels + Deforestation Melting Ice and Permafrost Rising Sea Levels Ocean Warming Ocean Acidification Extreme Weather Events Changes to Food Production Threats to Human Health Declining Biodiversity

Weather  Atmospheric Conditions  Short Term (days, weeks) Severe Weather, Hurricanes, Blizzards etc. Climate  Atmospheric Conditions  Long Term (30+ years) Glaciers, Sea Level Rise, Droughts

Climate Uneven distribution of solar energy + rotation of earth. Results in winds and ocean currents.

Climate Zones Defined mostly based on average temperature and precipitation over long periods of time. Three major zones – tropical, temperate, and polar.

Greenhouse effect  Storage of heat in atmosphere  Shift in traps heat  CO 2, CH 4, H 2 O, N 2 O

Historical Climate Last Ice AgeCurrent

Methods of Climate Research  Instrumental Record -Temperature form 1880-Present -CO 2 since 1960  Historical Records -Journals, Books etc. -qualitative vs quantitative  Paleo-proxy record (Paleoclimatology) proxy = not temperature but correlated with it -Tree Rings -Pollen -Sediments -Carbon 14 -Ice Cores -Corals

Ignore the next few slides, the nitty gritty details will not be on the exam! O.K. Jay exaggerated – maybe it would be a good idea to know one method.

Tree Rings 10,000 year record Precipitation Temperature

Sediments Millions of years Types of rocks Fossils (shells) – Foraminifera/Diatoms Chemistry, Temperature, 18 O vs. 16 O

Ice Cores 100,000 years Small bubbles of air – gasses, chemicals, volcanic ash Paleo-isotopic composition

Pollen Sediment Cores, Ice Core, etc. Abundance/Type related to climate

Coral Reefs Hard Skeleton of CaCO 3 Measure ratio of 18 O vs. 16 O

Carbon - 14 Proxy for Solar Activity Higher “Medieval Warm Period” – 1000 A.D. Lower “Little Ice Age” A.D. *can explain some global warming < 50,000 years

Natural Patterns in Climate Change Milutin Milankovitch (1920’s) 20,000, 40,000 and 100,000 yr. – Earths Wobble Medieval Warm Period AD Little Ice Age AD

Solar Output Solar Forcing Medieval Warm Period AD Little Ice Age AD 0.25%

Volcanic Activity Volcanic Aerosols reflect light, decrease temperature 1991 Mt. Pinatubo - ↓ 3 W/m 2 ↓ 4 °F Tambora 1816 – Snow in June, Killing Frosts in July Little Ice Age

Ocean Currents Meridional Overturning Circulation (MOC) Density Driven Ocean Currents (“salt”) Cold Sinks, Warm Rises Europe 9 °F warmer (Book up to 17 °F) If it stops could lead to cooling (off-setting some global warming)

Start paying attention again! The rest of the material will be on the exam!

Carbon Dioxide and Climate  Historically Temp and CO 2 correlate well  No other methods correlate as well

Carbon Dioxide and Climate  Svante Arrhenius ( )  CO 2 main factor  ppm  Current – 393 ppm  ppm  2100 – 1,390 ppm  Ecological Tipping Point? -450 ppm!

Human Causes  Greenhouse Gasses ↑  Fossil Fuels ↑  Deforestation ↑  Aerosols ↓ Natural Causes  Carbon Cycle ↓↑  Sequestration  Volcano’s ↓  Solar Cycles ↓↑  Earths Wobble ↓↑  Ocean Currents ↓↑

Human Contributions to Climate Change  Fossil Fuels (CO 2 )  Burning of wood (soot)  Deforestation (C – cycle)  USA – 25%  USA – 1,000x  China – 200x  Carbon Footprints (next)

Carbon Footprints

Intergovernmental Panel on Climate Change (IPCC)  2,500 scientists  29,000 data sets  5 reports – 1990,1995, 2001, 2007 and 2014  3 Main Points Temperature and CO 2 ↑ Human have a direct impact Climate already changing *Are scientists right 100% of the time? 3 – Facts to Consider  25 warmest years have occurred since 1980  Glaciers shrinking/Sea Ice melting  Rainfall pattern changing *Climate or Weather?

Counterarguments to Climate Change  Weather vs Climate  Not Experts (Its complicated)  Scientists normally “conservative”

Politics and Money

 Rapidly Changing Climate  Melting Ice and Permafrost  Rising Sea Levels  Ocean Warming  Ocean Acidification  Extreme Weather Events  Changes to Food Production  Threats to Human Health  Declining Biodiversity Impacts of Climate Change

Rapid Climate Change  Normally occurs over 1,000+ years  Current changes < 100 years  2-13 °F 1

Melting Ice and Permafrost  Warming worse at poles (2x)  ↓ 39% ( ), gone by 2040?  Effects global climate  Sea Level Rise (23’!)  Glaciers – source of fresh water  Permafrost contains methane (CH 4 )  23x worse, only lives 12 years  Feedback loop/tipping point 2

Temp  Temp 1 Temp Native Species Endangered Species Total population so small that risk of extinction is likely Degradation  Complex Interrelated Web  Pollution  Water Quality Facts: 1. Provide 87% Commercial Energy (92% USA) 2. Harmful Environmental Impacts (1 million deaths/year, 68,000 USA) 3. Creates CO 2 – Greenhouse gas/Global Warming

Pollution (Ch. 11,12) Climate Change (Ch. 13) Population (Ch. 2) Integrated Pest Management Fossil Fuels Renewable Energy Empower Women Demographic Transition Reduce Poverty Family Planning Ex: Indonesia Norway, Denmark

Light Crude 77% in OPEC (2% USA) Low Pollution Easy to Refine EROEI of Low-Quality Low Capacity Diffuse Wind, Solar, Nuclear Heat/Moving Molecules

Problems with Nuclear Power Low Net Energy Yield 35% Efficient 82% Lost Safety Issues Safety is Expensive 3 Mile Island Chernobyl Fukushima Radioactive Waste 10,000 year storage Leaks Terrorists/Accidents High Costs Initial Investment Large Safety Costs Disposal Nuclear Proliferation Civilian → Military 57 countries

Reduce Carbon Footprints 43% of Energy is Wasted Shift Energy Sources Increase use of Natural Gas VS % of Commercial Energy Natural Gas Leaks (CH 4 ) Expensive!