17 TH MILLER/SPOOLMAN LIVING IN THE ENVIRONMENT Chapter 19 Climate Control and Ozone Depletion

Core Case Study Melting Ice in Greenland Largest island Glaciers cover _______ of the island Hold ______ of the world’s fresh water Appear to be melting at an __________________ rate Effect on sea level if melting continues 1 meter rise by 2100 If all of Greenland’s ice melted the rise would be _______ 80% 10% accelerated 7 meters

Summer Melt Increases cires.colorado.edu

19-1 How Might the Earth’s Temperature and Climate Change in the Future? Concept 19-1 Considerable scientific evidence indicates that the earth’s atmosphere is warming, because of a combination of natural effects and human activities, and that this warming is likely to lead to significant climate disruption during this century.

Weather and Climate Are Not the Same Weather is _____________________ changes Temperature Air pressure Precipitation Wind Climate is ________________ conditions in a particular area over a long period of time at least _____ decades Focuses on temperature and precipitation Fluctuations are normal short - term average 3

Climate Change is Not New Over the past 3 billion or more years the climate has been altered by Changes in the sun’s ________________ of energy Impacts by meteors or volcanic emissions…puts large amounts of __________ into the atmosphere Slight changes in the earth’s ____________ Concentrations of ________ in global air Global ice cover that ________________ incoming solar energy (albedo affect) ocean circulation output dust orbit gases reflects

Fig. 19-2a, p Average surface temperature (°C) Thousands of years ago Present prolonged periods of global ____________ and ____________ coolingwarming

Estimated Changes in the Average Global Temperature of the Atmosphere Fig. 19-2, p. 494 Over the past 10,000 years, we have been in an _______________ period Over the past 1,000 years, our temperature has been relatively ______________ interglacial stable

Fig. 19-2b, p Average surface temperature (°C) Year Over the past 100 years, we have seen an overall trend of a temperature _________________ increase

Fig. 19-2d, p Temperature change (°C) Year

How Are Past Temperature Changes Determined? Past temperature changes are estimated through analysis of a number of types of evidence, including… Radioisotopes in ____________ and fossils _________________ in ocean sediments Tiny bubbles of ancient air found in _______________ ____________ from the bottoms of lakes and bogs Tree __________ Temperature measurements taken regularly since __________ rocks plankton ice cores Pollen rings 1861 National weather services, governments, etc.

Science: Ice Cores Are Extracted by Drilling Deep Holes in Ancient Glaciers Fig. 19-3, p. 495

Our Climate, Lives, and Economies Depend on the Natural Greenhouse Effect Along with solar energy, a natural process called the _______________________, warms the earth’s lower atmosphere and surface Heat radiated into the atmosphere causes greenhouse gas molecules to __________ and release infrared radiation with an even longer wavelength into the lower atmosphere. Water vapor ________ Carbon dioxide _______ Methane _______ Nitrous oxide _______ Greenhouse effect Radiated by atmosphere as heat Heat added to troposphere greenhouse effect vibrate H2OH2O CO 2 CH 4 N2ON2O

Fig. 3-4, p. 57 Solar radiation Re fl ected by atmosphere Radiated by atmosphere as heat UV radiation Lower Stratosphere (ozone layer) Most UV absorbed by ozone Visible light Heat added to troposphere Troposphere Heat radiated by the earth Greenhouse effect Absorbed by the earth Without the natural greenhouse effect our planet would be ___________ and ____________________ UV rays are not a factor in the greenhouse effect because they are absorbed by the _______________________ ozone layer frigiduninhabitable

Human Activities Emit Large Quantities of Greenhouses Gases Since the Industrial Revolution, many ____________ actions have led to significant increases in greenhouse gases (CO 2, CH 4, and N 2 O) Burning of ___________________ for industry and transportation Burning __________ to generate electricity __________________ ________________ and agriculture Ice core studies show a correlation of rising CO 2 and CH 4 with rising global ___________________ and sea ____________ over the past 400,000 years human fossil fuels coal Deforestation temperatures levels

Atmospheric Levels of CO 2 and CH 4, Global Temperatures, and Sea Levels Fig. 19-4, p. 496

Correlation of CO 2 and Temperature Fig. 19-5, p. 497

IPCC Report (1) The Intergovernmental Panel on Climate Change _______ has been researching climate change for almost three decades… Consists of a team of more than ___________ scientists One of the most extensive studies ever completed…have poured over tens of thousands of peer reviewed studies General agreement that… The earth’ s climate has warmed by about ______ since 1980 Human activities are ___________ to alter the planets’ climate during this century IPCC F° likely

IPCC Report (2) 2007 IPCC report… Nearly ___________ pages long __________ different authors In 2010, reviewers found only ____ minor errors in the entire report No problems diminished the findings of the study 3,

IPCC Report (3) Also analyzed 19 climate models, which are ___________________ models that simulate interactions among earth’s sunlight, clouds, landmasses, oceans, ocean currents, concentrations of greenhouse gases and pollutants, and positive or negative feedback loops Run on “super computers” Models make _____________________ and not predictions Projected that earth’s mean temperature will increase by _____________ between 2005 and 2100 mathematical projections 3.6 – 8.1 F°

Factors Affecting Projected Climate Change Scientists have identified several natural and human- influenced factors that might amplify (give _____________ feedback to) or dampen (give ______________ feedback to) the projected changes in the average atmospheric temperature __________________________ The __________ ____________________ ______________________ _____________ air pollution positive negative CO 2 emissions Waste heat sun oceans Cloud cover outdoor

CO 2 Emissions Play an Important Role (1) We are altering the natural carbon cycle by… _________________ fossil fuels and forests _______________ forests (help remove CO 2 ) NOAA data shows that atmospheric CO 2 rose from _______ ppm in about 1850 to _______ ppm in 2010 If emissions continue at their current rate, CO 2 are likely to rise to… _________ ppm by 2050 _________ ppm by 2100 burning clearing ,390 Currently over 400

CO 2 Emissions Play an Important Role (2) A number of major climate models project that we need to prevent CO 2 levels from exceeding ________ ppm Estimated threshold or irreversible ______________ point that could set into motion large-scale climate change Climate scientist James Hansen recommends bringing CO 2 levels back down to _________ ppm 450 tipping 350

James Hansen Fig. 19-C, p. 502 Stood before a U.S. Congressional Committee in 1988 stating that he was 99% sure that greenhouse gases and atmospheric warming are a grave threat Helped to create the __________ Worked with NASA to develop several climate _______________ IPCC models

CO 2 Emissions Play an Important Role (3) Largest emitters, China 2.United States 3.European Union (27 countries) 4.Indonesia 5.Russia 6.Japan 7.India

Cumulative CO 2 emissions, Figure 15, Supplement 9

Waste Heat Also Plays a Role in Climate Disruption Because of the second law of thermodynamics, burning any fuel releases ______ temperature waste heat into the environment Double punch: waste heat and the release of CO 2 Many ________________ technologies produce large amounts of waste heat Incandescent light = _________ Internal combustion engines = ________ Coal burning power plants = __________ Nuclear fuel cycle = __________ low inefficient 95% 80% % 92%

What Role Does the Sun Play? Some people have proposed that increased atmospheric temperature is simply due to a hotter sun or increased ______________________. Not so….a hotter sun would heat the ___________________ first Since 1975 Troposphere has ________________ Stratosphere has ____________ solar output stratosphere warmed cooled

What Role Do the Oceans Play in Projected Climate Disruption? The oceans _______________ CO 2 from the atmosphere as part of the carbon cycle As water temperature increases, the ability of oceans to absorb CO 2 ________________ Similar to how warm pop tastes flat Last century: C° increase (0.6 – 1.2 F°) Could lead to less CO 2 absorption and __________ atmospheric warming absorb decreases more

What Role Do the Oceans Play in Projected Climate Disruption? Example of a positive feed-back loop Warmer temperatures Warmer oceans less CO 2 absorption

What Role Do the Oceans Play in Projected Climate Disruption? Recent studies show that increasing levels of CO 2 have increased the ________________ of the ocean’s surface by _______ during the past 200 years Threatens _____________ and other organisms with shells Decreases levels of ______________________ Primary producers of the oceans that absorb CO 2 acidity 30% coral phytoplankton

What Role Do the Oceans Play in Projected Climate Disruption? Another example of a positive feed-back loop warmer temps melting glaciers less reflection of sun’s rays

There Is Uncertainty about the Effects of Cloud Cover on Global Warming Warmer temperatures create __________ clouds Thick, low altitude cumulus clouds: _____________ surface temperature by reflecting sunlight back into space Thin cirrus clouds at high altitudes: ___________ surface temperature by preventing heat from escaping Effect of ________ contrails on climate temperature Expand and turn into cirrus clouds more lower increase jet

Cumulus Clouds and Cirrus Clouds Fig. 19-8, p. 503 Reflect sunlight Trap some heat in

Outdoor Air Pollution Can Temporarily Slow Global Warming Aerosol and soot pollutants (SPM) Light colored sulfate particles tend to __________ sunlight and cool the lower atmosphere May have played a role in cooling the atmosphere between 1880 and 1970 Dark __________ particles have a warming effect _____ greater than previously estimated reflect soot 4 x

Outdoor Air Pollution Can Temporarily Slow Global Warming Climate scientists do NOT think that aerosols or soot particles will affect climate change very much because… Fall back to the earth or are washed out of the lower atmosphere within ___________ or _____________ Reduction: especially in developed countries weeksmonths

Review Questions What two general conclusions did the IPCC form regarding climate change? What is considered to be the ecological threshold or tipping point for atmospheric CO 2 in parts per million? 1 F°increase since 1980 Human activity will likely alter our climate this century 450 ppm

Review Questions How may warmer temperatures create positive feedback loops contributing to further atmospheric warming? Warmer temps  less CO 2 absorption by ocean  more GH gases

19-2 What Are Some Possible Effects of a Warmer Atmosphere? Concept 19-2 The projected rapid change in the atmosphere's temperature could have severe and long-lasting consequences, including increased drought and flooding, rising sea levels, and shifts in the locations of croplands and wildlife habitats.

Enhanced Atmospheric Warming Could Have Serious Consequences Why are we so concerned? Most historic changes in temperature of the lower atmosphere took place over ________________ of years Our current problem is urgent because we are facing a _______________ projected increase in the average temperature of the lower atmosphere Will affect _____________ we grow our food May cause the premature extinction of up to ______ of the world’s species Tropical diseases may ______________ out of their current range thousands rapid where half spread

Severe Drought Is Likely to Increase Accelerate global warming, lead to ______ drought Increased ____________________ Declining stream flows, _______ lakes, lower water tables Dry climate ecosystems will ______________ Water ____________________ more wildfires dry expand shortages

More Ice and Snow Are Likely to Melt (1) Global warming will be worse in the __________ region Ice typically ________________ sunlight As it melts, there is less ice and more ________ areas that will _________ more solar energy This causes warmer temperatures and more ice/snow melt…another example of a _________________ feedback loop Mountain glaciers affected by Average ____________________ Average _____________ temperatures polar reflects dark absorb positive snowfall warm

Shrinking Athabasca Glacier in Canada Fig. 19-9, p. 506 Glaciers disappearing from Himalayas in Asia Alps in Europe Andes in South America Greenland Warmer temperatures When mountain glaciers disappear, there will be far less water in many major __________________ rivers

Permafrost Is Likely to Melt: Another Dangerous Scenario Arctic tundra permafrost soils contain much locked up ____________ (CH 4 ) __________ the amount of carbon dioxide emitted annually from burning fossil fuels If permafrost in Arctic region melts, more greenhouse gases will be ___________________ into the atmosphere Arctic tundra is an important ______________ ground for tundra bird species and provides ______________ land for caribou methane 50 – 60 x released breeding grazing

Projected Decreases in Arctic Tundra in Russia, Fig , p. 507

Sea Levels Are Rising (1) World’s average sea level will most likely rise _____________________ by 2100 Due to the ________________ of warm water and melting ________________ ice 2009 study indicates that the melting of just ______ of Greenland’s ice sheet will cause a __________ rise in sea level. 0.8 – 2 meters expansion Land-based 15% 1 meter

Sea Levels Are Rising (2) Projected irreversible effect Degradation and loss of ________ of coastal estuaries, wetlands, and coral reefs Disruption of coastal ______________ __________________ of Low-lying barrier islands and coastal areas Agricultural lowlands and deltas Coastal cities _________________ of freshwater aquifers Submergence of low-lying _____________ in the Pacific and Indian Oceans and the Caribbean 1/3 fishing Flooding Contamination islands

Areas of Florida to Flood If Average Sea Level Rises by One Meter Fig , p. 507

Low-Lying Island Nation: Maldives in the Indian Ocean Fig , p. 508

Extreme Weather Is Likely to Increase in Some Areas Heat waves and droughts in some areas Could __________ large numbers of people Prolonged rains and flooding in other areas May lead to fewer, but stronger _______________ kill hurricanes

Climate Disruption Is a Threat to Biodiversity (1) 2007 IPCC report: projected climate change is likely to… Upset _____________________ _________________ biodiversity Degrade ecosystem ____________________ Most susceptible ecosystems Coral reefs Polar seas Coastal wetlands High-elevation mountaintops Alpine and arctic tundra ecosystems Decrease services

Climate Disruption Is a Threat to Biodiversity (2) Organisms that could increase with global warming are… __________________ _______________ __________________ Exploding populations of mountain pine _________ have munched their way through large areas of lodge-pole pine forest insects fungi microbes beetles

Exploding Populations of Mountain Pine Beetles in British Columbia, Canada Fig , p. 509

Agriculture Could Face an Overall Decline Regions of farming may _____________ Decrease in tropical and subtropical areas Increase in northern latitudes May lead to __________ productivity; soil not as fertile Hundreds of millions of people could face starvation and malnutrition shift less

A Warmer World Is Likely to Threaten the Health of Many People Deaths from _______________ will increase Higher temperatures can cause Increased flooding Increase in some forms of air pollution, more O 3 More insects, microbes, toxic molds, and fungi Increase in environmental _________________ Heat waves refugees

Detection of Dengue Fever in Mosquitoes, as of 2005 Fig , p. 510

Review Questions What is considered to be the ecological threshold or tipping point for atmospheric CO 2 in parts per million? How will warmer oceans create positive feedback loops contributing to further atmospheric warming? Why is climate disruption considered to be an urgent issue? 450 ppm Increased acidity…less phytoplankton….less CO 2 absorption Rapid increase in atmospheric temps. Farming, sea levels, biodiversity