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Warm up Kahoot Quizlet live
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AGENDA Warm up Test on exit ticket Begin last unit: climate
change and sustainability Closure
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Choose a project –first and 4th
Talk with your partner (s) Groups no larger then 4 Decide on a unique, authentic project Create the project over the next 5-6 days Third period: Complete a climate book
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Title Create a title for your project Climate Change
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Define climate Define weather Answer this question: What is the difference between climate and weather?
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Koppen climate classification system
Do these: 1. define 2. cut and sort the hand out 3. include the climate map in your project (either digital/paper) 4. Mark North Carolina on the map 5. Answer this question: What is our Koppen system in North Carolina?
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Warm up
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Review Climate vs weather Koppen climate classification
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What factors determine climate?
Latitude - Where you are positioned north or south of the equator Altitude (elevation) - How high you are, higher = cooler Prevailing Winds - depends where the winds come from, warm or cold areas Distance from Oceans or water - water moderates climate, closer you are, less variation you get Ocean Currents - Ocean currents can bring warm air from far away (global circulation) Geography - What the area is like. Topography, vegetation, nearness to mountains etc all affect the climate.
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Possible test questions: closure
What is the difference between climate and weather? A. Climate averages the weather conditions in a specific place over a long period of time, while weather describes the state of the atmosphere at a specific moment of time B. Weather averages the weather coniditons in a specific place over a long period of time, while climate describes the state of the atmosphere at a specific moment in time. C. Climate describes the weather conditions at night, while weather describes the conditions during the daytime D. There is not a differenc between climate and weather Which of these is NOT a factor that determines the climate of a place? A. Latitude B. Wind patterns C. Longitude D. elevation
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Warm up Quizlet live with new words
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Review Climate vs weather Koppen climate
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NC Essential standards
EEn • Explain major climate categories (Köppen climate classification system – temperate, tropical, and polar). • Compare weather and climate. EEn • Summarize natural processes that can and have affected global climate (particularly El Nino/La Nina, volcanic eruptions, sunspots, shifts in Earth’s orbit, and carbon dioxide fluctuations). EEn • Outline how deforestation and the burning of fossil fuels (linked to increased industrialization) contribute to global climate change.
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Natural causes of climate change =Main title
Subtitles (leave room to write about each one and draw pictures/graphs Milankovitch cycles Solar cycles Volcanic eruptions Plate tectonics
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Milankovitch Cycles Named after a Serbain mathematician,
Milutin Milankovitch EXTREMELY long term effects that scientists think may be the cause of the ice ages. These are movements of the Earth that affect the amount of solar radiation that it gets.
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Milankovitch Cycles Earth’s wobble, tilt, and orbit Precession
Obliquity Eccentricity
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Milankovitch Cycles Precession
Direction of the Earth’s axis changes over time The Earth wobbles like a top on its axis 26,000 year cycle
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Milankovitch Cycles Obliquity
The tilt angle of the Earth’s axis changes over time The greater the tilt the greater the differences in the seasons. 40,000 year cycle
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Milankovitch Cycles Eccentricity
Varying shape of Earth’s orbit, e.g. how elliptical it is 100,000 year long cycle Click on the “Animation” link for a hot link to the web. To get back to the Powerpoint presentation, look along the bottom toolbar and click on the powerpoint logo. Animation
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Solar Cycles Sunspots are storms on the surface of the sun and are associated with extremely strong magnetic activity, solar flares hot gaseous emissions These follow an 11 year cycle. Scientific research estimates that normal fluctuations due to Solar Cycles increase or decrease solar radiation reaching Earth by only 0.1% - 0.2%. Note that a prolonged period of virtually no sunspot activity as occurred during the 17th century can have a significant influence on Earth’s climate. The “Maunder Minimum” from is directly associated with the “Little Ice Age”
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Images of the Sun’s changing surface activity
Modified from:
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400 Years of Sunspot Activity
Modified from Note the period between on the graph the “Little Ice Age” that students discovered with the Tree Core activity was thought to be at least partly due to very low sunspot activity. The figures show almost a complete cycle – 1980 – 1989.
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Volcanic Eruptions Volcanic eruptions of ash and gases into the troposphere and above cause SHORT TERM cooling (few years). The gases released are mainly water (H2O), carbon dioxide (CO2) and sulfur dioxide (SO2). The 1st 2 do not change ambient levels by much. But the SO2 reacts with H2O to form sulfates. Sulfates increase the brightness (albedo) of clouds, reducing the solar radiation reaching Earth. The large volumes of ash also block some incoming solar radiation but the effect is less significant and more short lived. An excellent web site for information on volcanoes and climate change is: Note: volcanoes release very little CO2 in comparison to human sources. The estimate of annual CO2 release by all volcanic activity is 130 – 440 megatons. This is dwarfed by annual human source emissions of about megatons.
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Volcanic Eruptions Do Volcanic eruptions cause long term climate change? Apparently not. There is evidence of slight warming at some times, and slight cooling at other times. In these cases any temperature changes are minimal and short lived. Interesting point: During the time before and at the beginning of the Little Ice Age, there was an increased incidence of volcanic activity – enhancing the effect of the Sun Spot minimum. Cole-Dai, Jihong Volcanos and Climate. (Advanced Preview) In: WIREs Climate Change John Wiley & Sons Ltd., New York. 16 pages. Note – some scientists think that many millions of years ago there may have been periods of extreme volcanic activity caused by very active tectonic movements. It is possible that in these cases a more prolonged/significant impact on climate may have occurred.
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Plate Tectonics Plate Tectonics and associated Continental drift
Have been exerting their effect on the Earth’s geography over billions of years Have shaped the continents as we know them The impact on climate (very long term, and in the past) was: by changing land mass and ice caps (size & location) and changing ocean circulation patterns which transport heat around the Earth and in turn influences atmospheric circulation processes. The hot link shows an animation of Plate Tectonics. A slower animation can be found at:
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Review:El Niño/La Niña
El Niño is a large scale change in oceanic and atmospheric circulation in the eastern equatorial Pacific and involves rapid, large scale warming of the sea-surface. Peruvian fishermen have noticed this because the warming is linked to a stop in the upwelling of deep nutrient-rich cold water just off their coast. During an El Niño event, this lack of nutrients reduces the productivity of the ocean and fish populations decline dramatically. La Niña is the opposite, a rapid cooling in this area.
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Review: El Niño/La Niña
Impacts: Tradewinds are weaker than average Causing pools of warm water to move eastward across the ocean towards South America The cold upwelling water is reduced, the water warms (and levels rise) causing the fish to move away Warm waters produce lower air pressures, which increase convection, and increase rainfall – which can cause flooding. In tropical western Pacific (e.g. New Zealand) there is a slight decrease in ocean levels, lower convection and drought conditions
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El Niño and climate More precipitation in the southwest US
Mild winter temperatures over western Canada and north western USA • Above average precipitation in the Gulf Coast, including Florida • A drier than average period in Ohio and pacific northwest reduces the instances of hurricanes in the Atlantic To update El Niño/La Niña conditions, go to: NOAA’s Climate Predication Centre at
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La nina and climate • Stronger winds along the equator • weaker jet stream • temperatures are above average in the southeast and below average in the northwest • More hurricanes in the Atlantic • More tornados
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Is there climate change?
Although El Niño events are not new (there is evidence they have been occurring for hundreds of years), a distinct change in the behavior of this event beginning in the mid- 1970�s has some worried that human-induced climate change may be having its effect. These recent changes include two �extreme� El Niño events (the strongest in this century, the 1982 to 1983 event and the longest of this century, the 1990 to 1995 event) and an increased frequency of El Niño relative to the past 50 years. As is the case with most attempts to pen a modern day observation to global warming, this evidence cannot rule out �natural variation.� Periods of high El Niño activity have occurred before, as for example from 1880 to That being said, some computer models of climate change predict precisely what is being observed today: increased likelihood of El Niño (with one study suggesting an increase of once every five years to once every three years); warming of the tropical Pacific with greater warming in the east than in the west (a pattern generally associated with El Niño); and a possible increase in El Niño severity. In so much as El Niño is a natural phenomena, it is something we need to live with, just as we do with earthquakes and hurricanes. However, if the current El Niño trend continues, the consequences could take a heavy toll on the entire world, disrupting everything from the U.S. insurance industry to the prospect for worldwide sustainable development.
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Main title: Human causes of climate change
Subtitles (leave room to write about each one and draw pictures/graphs 1. Deforestation 2. burning fossil fuels 3. Large scale development (urbanization) which creates heat islands All of these increase greenhouse gases
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Deforestation When forests are cut down, carbon absorption ceases
carbon stored in the trees is released into the atmosphere as CO2 if the wood is burned or even if it is left to rot after the deforestation process. Slash and burn releases CO2
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Burning fossil fuels burning of fossil fuels like coal and oil has increased the concentration of atmospheric carbon dioxide (CO2). This happens because the coal or oil burning process combines carbon with oxygen in the air to make CO2.
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Large scale development (urbanization)
Heat islands: cities are significantly warmer than surrounding areas because: Impermeable surfaces-asphalt that cover roads and parking lots and roofs absorb enormous amounts of heat. Lots of cars all in the same place In the summer, whirring air conditioners channel even more heat out of buildings and into the air. Very few plants or water to absorb or reflect heat
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Closure What are your personal thoughts on climate change and global warming?
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Warm up Go to my links under the climate change folder
Click on warm up 5/16
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Review Factors that determine climate Natural impacts on climate
Human impacts on climate
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What factors determine climate?
Latitude - Where you are positioned north or south of the equator Altitude (elevation) - How high you are, higher = cooler Prevailing Winds - depends where the winds come from, warm or cold areas Distance from Oceans or water - water moderates climate, closer you are, less variation you get Ocean Currents - Ocean currents can bring warm air from far away (global circulation) Geography - What the area is like. Topography, vegetation, nearness to mountains etc all affect the climate.
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Possible test question
Which of these is NOT a factor that determines the climate of a place? Latitude Wind patterns Longitude elevation
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Natural causes Milankovitch cycles: precession, obliquity, and eccentricity Solar cycles Volcanism Plate tectonics El nino and la nina
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Milankovitch Cycles Earth’s wobble, tilt, and orbit Precession
26,000 years Obliquity 40,000 years Eccentricity 100,000 years
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Solar cycles Follow an 11 year cycle.
Scientific research estimates that normal fluctuations due to Solar Cycles increase or decrease solar radiation reaching Earth by only 0.1% - 0.2%.
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Volcanism Short term effect
Small effects only- slight warming and slight cooling Ash can block sunlight
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Plate tectonics Happening for billions of years shaped the continents
The impact on climate (very long term, and in the past) was: by changing land mass and ice caps (size & location) and changing ocean circulation patterns which transport heat around the Earth and in turn influences atmospheric circulation processes.
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El nino/la nina
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El Niño and climate More precipitation in the southwest US
Mild winter temperatures over western Canada and north western USA • Above average precipitation in the Gulf Coast, including Florida • A drier than average period in Ohio and pacific northwest reduces the instances of hurricanes in the Atlantic To update El Niño/La Niña conditions, go to: NOAA’s Climate Predication Centre at
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La nina and climate • Stronger winds along the equator • weaker jet stream • temperatures are above average in the southeast and below average in the northwest • More hurricanes in the Atlantic • More tornados
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Human causes Deforestation Burning fossil fuels urbanization
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NC essential standards
EEn Explain the concept of the greenhouse effect including a list of specific greenhouse gases and why CO2 is most often the focus of public discussion EEn • Explain how changes in atmospheric composition contribute to ocean acidification. Analyze its effect on ocean life and its connection to global climate change. • Explain how changes in global temperature have and will impact sea level. • Analyze how sea level has been affected by other earth processes such as glaciations and tectonic movements. Consider long- and short-term changes.
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Agenda Finish day 2 and begin day 3
Look over rubric NOTE: students not working on the project will lose points each day they are not working. The experiment is over by the sink. After the chemical reaction is complete, Mrs. Chapel will write final results on the paper over there. Until then, you should read the thermometers yourself. Experiment questions and data table are available in digital (on my ppt) and hard copy form
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DAY 2: The greenhouse effect
Warming effect on the air caused by heat rising from the surface of the Earth and being trapped by gases in the troposphere.
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What are the greenhouse gases?
Carbon dioxide Methane Nitrous oxide Water vapor Fluorinated gases
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Carbon cycle cont… Carbon dioxide: stays in the atmosphere for a long time (800 years), Has caused most of the warming, created when fossil fuels are burned, cement is made, Water vapor: most abundant heat-trapping gas, only in the atmosphere a short time, may be one of the biggest contributors to climate change Methane: produced during the production and transport of fossil fuels, also produced by livestock and rotting organic matter in landfills. Nitrous oxide: Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste. Fluoronated gases: synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes. synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes.
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Lab activity Observe the two containers and answer these questions. Put the table and answers in your project 1. Describe the experimental set up. 2. Which container do you think is modeling the greenhouse effect? 3. What greenhouse gas do you think is causing the difference in temperature? Temperature initial Temperature final Bottle 1 (green) Bottle 2 (pink)
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Carbon cycle The movement of carbon, in its many forms, between the atmosphere, oceans, biosphere, and geosphere
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Carbon sinks Anything that absorbs more carbon than it releases
Includes forests, soils, the oceans
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Carbon source Anything that releases more carbon than it absorbs.
Includes: deforestation, burning of fossil fuels, agriculture, and cement production
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Global warming vs climate change
refers only to the Earth’s rising surface temperature includes warming and the “side effects” of warming—like melting glaciers, heavier rainstorms, or more frequent drought.
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closure What is a consequence that increasing human population could have on the Earth’s climate? Decreasing global temperatures, due to decrease use of fossil fuels Increasing global temperatures, due to increased use of fossil fuels A decreased heat island effect, due to less people living and working in urban areas All of the above
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Warm up Quizziz
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Day 3: Earth’s oceans and climate change
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Review Greenhouse effect Global warming Carbon cycle
Carbon sinks and sources
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Greenhouse effect
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Greenhouse gases (list some)
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Global warming a gradual increase in the average temperature of the Earth's atmosphere and its oceans, a change that is believed to be permanently changing the Earth's climate.
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Carbon cycle
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Carbon sinks vs carbon sources
Absorbs more carbon than it releases Examples: ocean, soils, forests Releases more carbon than it absorbs Examples: deforestation, burning fossil fuels
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Agenda Finish day 3 and begin day 4 NC Essential standard:
EEn • Explain how changes in atmospheric composition contribute to ocean acidification. Analyze its effect on ocean life and its connection to global climate change. Explain how changes in global temperature have and will impact sea level. Analyze how sea level has been affected by other earth processes such as glaciations and tectonic movements. Consider long- and short-term changes.
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Ocean Acidification The ongoing decrease in the pH of the Earth’s oceans caused by the uptake of carbon dioxide from the atmosphere.
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Atmospheric composition and ocean acidification
The oceans are absorbing carbon dioxide (CO2) from the atmosphere this is making the oceans more acidic (that is, decreasing the pH of the oceans). In the past 200 years the oceans have absorbed approximately half of the CO2 produced by fossil fuel burning and cement production.
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Affects on ocean life Photosynthetic algae and seagrasses may benefit from higher CO2 conditions decrease reef growth Dissolves existing reefs, reef, death Makes it hard for oysters, clams, sea urchins, shallow water corals, deep sea corals, and calcareous plankton to make shells. Shells can be deformed Coral bleaching-define it from vocabulary
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How are ocean acidification and climate change connected?
The ocean is the earth’s largest carbon reservoir, containing more than 50 times as much CO2 as the atmosphere. As more man-made C02 has entered the atmosphere, more of the gas has entered the ocean. climate change does not directly cause acidification of the oceans per se; rather climate change and ocean acidification are two separate and serious problems that are related because both are caused by excessive emissions of carbon dioxide.
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New title: Sea Level Rise
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Thermal expansion of ocean water
Ocean water expands as it warms-because of the increase in ocean heat content Remember heating items causes them to expand Expansion of ocean water causes sea level rise
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Other causes of sea level change: Glaciation
As glaciers grow, the water that contributes to their expansion evaporates from the oceans, falls as snow in the glacier’s accumulation area, and remains locked in the glacier as glacier ice. The longer this happens, the lower sea level becomes. When temperatures increase, glacier melting increases, and snow accumulation decreases. The newly released meltwater returns to the ocean and sea level rises.
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Other causes of sea level rise-tectonics
Land can be pushed up during continental continental collisions (creates folded mountains) or subduction of plates (creates volcanic mountains) Seafloor can open up during rifting or seafloor spreading Can change basin volumes and shapes Can move continents in positions that increase or decrease continental ice sheets
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Eustatic vs. isostatic level changes due to:
an alteration in the volume of water in the oceans a change in the shape of an ocean Always a global effect level change due to the result of an increase or decrease in the height of the land. Increase= the sea level falls decreases = sea level rises. always a local change Can be caused by tectonics
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closure 1. Sea level is expected to rise because of warmer climate due to the following: a. Oceans expand as they get warmer (thermal expansion) b. Glaciers and ice-sheets melt c. both a and b 2. All of the following are evidence of rapid climate change except a. rising sea level b. global temperature rise c. ocean acidification d. increase in the size of the Antarctic and Greenland ice sheets
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Warm up Kahoot
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Review Ocean acidification Sea level rise Thermal expansion
Melting of ice Eustatic isostatic
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Atmospheric composition and ocean acidification(decrease in pH of oceans)
The oceans are absorbing carbon dioxide (CO2) from the atmosphere this is making the oceans more acidic (that is, decreasing the pH of the oceans). In the past 200 years the oceans have absorbed approximately half of the CO2 produced by fossil fuel burning and cement production.
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Affects on ocean life Photosynthetic algae and seagrasses may benefit from higher CO2 conditions decrease reef growth Dissolves existing reefs, reef, death Makes it hard for oysters, clams, sea urchins, shallow water corals, deep sea corals, and calcareous plankton to make shells. Shells can be deformed Coral bleaching-define it from vocabulary
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How are ocean acidification and climate change connected?
The ocean is the earth’s largest carbon reservoir, containing more than 50 times as much CO2 as the atmosphere. As more man-made C02 has entered the atmosphere, more of the gas has entered the ocean. climate change does not directly cause acidification of the oceans per se; rather climate change and ocean acidification are two separate and serious problems that are related because both are caused by excessive emissions of carbon dioxide.
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Thermal expansion of ocean water
Ocean water expands as it warms-because of the increase in ocean heat content Remember heating items causes them to expand Expansion of ocean water causes sea level rise
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Other causes of sea level change: Glaciation
As glaciers grow, the water that contributes to their expansion evaporates from the oceans, falls as snow in the glacier’s accumulation area, and remains locked in the glacier as glacier ice. The longer this happens, the lower sea level becomes. When temperatures increase, glacier melting increases, and snow accumulation decreases. The newly released meltwater returns to the ocean and sea level rises.
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Other causes of sea level rise-tectonics
Land can be pushed up during continental continental collisions (creates folded mountains) or subduction of plates (creates volcanic mountains) Seafloor can open up during rifting or seafloor spreading Can change basin volumes and shapes Can move continents in positions that increase or decrease continental ice sheets
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Eustatic vs. isostatic level changes due to:
an alteration in the volume of water in the oceans a change in the shape of an ocean Always a global effect level change due to the result of an increase or decrease in the height of the land. Increase= the sea level falls decreases = sea level rises. always a local change Can be caused by tectonics
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Agenda Finish the final day NC essential standard:
EEn Analyze actions that can be taken by humans on a local level, as well as on a larger scale, to mitigate global climate change. EEn Analyze how changes in global temperatures affect the biosphere (ex. agriculture, species diversity, ecosystem balance)
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How temperature/climate change affects the biosphere
1. agriculture Some crops grow better with increased temperatures, but increased heat can put livestock at risk Reduced yields in other crops like grains due to temperature increases Higher CO2 can increase yields Increased droughts damage/destroy crops and livestock Extreme temperatures and precipitation can prevent plant growth especially if there is flooding Many pests (insects, fungi, parasites) like warmer, wetter climates and damage crops or infect livestock
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How temperature/climate change affects the biosphere
2. Species diversity rapid climate change affects ecosystems and species ability to adapt and so biodiversity loss increases. Some species may benefit from climate change (including, from a human perspective, increases in diseases and pests-like invasive species) In addition to warming temperatures, more frequent extreme weather events and changing patterns of rainfall and drought can be expected to have significant impacts on biodiversity. More extinctions Coral bleaching occurs which decrease ocean biodiversity
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How temperature/climate change affects the biosphere
3. Ecosystem balance Species are forced to move into other ecosystems Migration and mating patterns change Habitat ranges shift north (in North America) Producers in food webs may die or decline More disease, pathogens, parasites
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Regional changes in climate (the southeast)
Increased temperatures Heavy downpours increased Periods of extreme drying and heatwaves Coastal regions experience sea level rise, more hurricanes and storm surges Freshwater/clean water availability will decline (due to saltwater intrusion in wells, increased evaporation) More Contaminated water because increased heat breeds bacteria No chilling period for some crops means they cannot grow in the southeast (like fruit)
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Some Evidence-the humans did it!!!
Natural changes alone can’t explain the temperature changes we’ve seen.- when models include only recorded natural climate they cannot accurately reproduce the observed warming of the past half century. The atmospheric concentration of CO2 has increased from a pre- industrial era (AD 1000 – 1750) concentration of approximately 280 parts per million (ppm) to around 383 ppm, The carbon in the atmospheric CO2 contains information about its source, so that scientists can tell that fossil fuel emissions comprise the largest source of the increase since the pre-industrial era. See for additional evidence
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Some Evidence that it is natural!!!!
Natural climate oscillates between warm periods and glaciation (milankovitch cycles and solar cycles)-we are currently coming out of a glaciation period Warming has happened before: The Paleocene-Eocene Thermal Maximum (PETM), which occurred around 56 million years ago, is the most recent event that we can compare today's warming to. Global temperatures rose at least 5°C (9°F), and the PETM warmth lasted 200,000 years before the Earth system was able to remove the extra CO2 from the atmosphere.
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Mitigation and adaptation ideas-see handout
Use renewable energy Protect forests, wetlands, and oceans Reduce, reuse, recycle Use public transportation whenever possible
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closure 1. A local government voted against the large-scale development of buildings and roads in the area. What could have been the motive behind their decision? A It could lead to a decrease in the average annual temperature in the area. B It could lead to the formation of heat islands, which may impact the microclimate in the area. C It could lead to the introduction of invasive species, which may impact the area. D It could lead to a decrease in acid rain production in the area. 2. Since 1901, global surface temperatures have risen at an average rate of 0.13°F every ten years. In which way could the average increase in global temperatures influence Earth? A by decreasing erosion within coastal ecosystems B by decreasing periods of drought in all water systems C by increasing the amount of flooding because of rising sea levels D by increasing the formation of sea ice within polar regions
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Warm up Game review-quizlet, flip quiz
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Agenda review Finish up and set up your projects for viewing
Gallery walk-vote on your favorite project Voting: Do not vote for you own 1. write down team names 2. write down at least 2 reasons you picked the team 3. write a detailed sentence that tells me your thoughts on climate change. 4. write down at least one thing you can do to lessen climate change.
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Review Temperature and climate effects on the biosphere
Climate impacts on the southeast Humans or natural? What is causing the changes. Mitigation and adaptation
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How temperature/climate change affects the biosphere
1. agriculture Some crops grow better with increased temperatures, but increased heat can put livestock at risk Reduced yields in other crops like grains due to temperature increases Higher CO2 can increase yields Increased droughts damage/destroy crops and livestock Extreme temperatures and precipitation can prevent plant growth especially if there is flooding Many pests (insects, fungi, parasites) like warmer, wetter climates and damage crops or infect livestock
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How temperature/climate change affects the biosphere
2. Species diversity rapid climate change affects ecosystems and species ability to adapt and so biodiversity loss increases. Some species may benefit from climate change (including, from a human perspective, increases in diseases and pests-like invasive species) In addition to warming temperatures, more frequent extreme weather events and changing patterns of rainfall and drought can be expected to have significant impacts on biodiversity. More extinctions Coral bleaching occurs which decrease ocean biodiversity
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How temperature/climate change affects the biosphere
3. Ecosystem balance Species are forced to move into other ecosystems Migration and mating patterns change Habitat ranges shift north (in North America) Producers in food webs may die or decline More disease, pathogens, parasites
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Regional changes in climate (the southeast)
Increased temperatures Heavy downpours increased Periods of extreme drying and heatwaves Coastal regions experience sea level rise, more hurricanes and storm surges Freshwater/clean water availability will decline (due to saltwater intrusion in wells, increased evaporation) More Contaminated water because increased heat breeds bacteria No chilling period for some crops means they cannot grow in the southeast (like fruit)
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Some Evidence-the humans did it!!!
Natural changes alone can’t explain the temperature changes we’ve seen.- when models include only recorded natural climate they cannot accurately reproduce the observed warming of the past half century. The atmospheric concentration of CO2 has increased from a pre- industrial era (AD 1000 – 1750) concentration of approximately 280 parts per million (ppm) to around 383 ppm, The carbon in the atmospheric CO2 contains information about its source, so that scientists can tell that fossil fuel emissions comprise the largest source of the increase since the pre-industrial era. See for additional evidence
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Some Evidence that it is natural!!!!
Natural climate oscillates between warm periods and glaciation (milankovitch cycles and solar cycles)-we are currently coming out of a glaciation period Warming has happened before: The Paleocene-Eocene Thermal Maximum (PETM), which occurred around 56 million years ago, is the most recent event that we can compare today's warming to. Global temperatures rose at least 5°C (9°F), and the PETM warmth lasted 200,000 years before the Earth system was able to remove the extra CO2 from the atmosphere.
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Mitigation and adaptation ideas-see handout
Use renewable energy Protect forests, wetlands, and oceans Reduce, reuse, recycle Use public transportation whenever possible
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Closure Climate change-human or natural? What do you think?
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