Carbon Cycle and Climate Change

Mrs. Cook

Environmental Science

Global Warming

• “What gets us into trouble is not what we don’t know…

it’s what we know and do nothing about.”

-Margaret Meid

The Carbon Cycle

• Producers convert carbon dioxide in the atmosphere into carbohydrates during photosynthesis.

• Consumers obtain carbon from the carbohydrates in the producers they eat.

•During cellular respiration, some of the carbon is released back into the atmosphere as carbon dioxide.

Some carbon is stored in limestone, forming one of the largest “carbon sinks” on Earth.

The Carbon Cycle

• Carbon stored in the bodies of organisms as fat, oils, or other molecules, may be released into the soil or air when the organism dies.

• These molecules may form deposits of coal, oil, or natural gas, which are known as fossil fuels.

• Fossil fuels store carbon left over from bodies of organisms that dies millions of years ago.

The Carbon Cycle

• Humans burn fossil fuels, releasing carbon into the atmosphere.

• The carbon returns to the atmosphere as carbon dioxide.

• Increased levels of carbon dioxide may contribute to global warming.

The Carbon Cycle

The Carbon Cycle

http://www.youtube.com/watch?v=HrIr3xDhQ0E

What is the Difference between Climate and Weather?

• Weather is an event such as rain, snow, wind, sunshine, fog, frost, etc. that occurs on a particular day in a particular place.

• Climate is an average of all the of weather in a particular place over a period of time (usually a 30 year period) and includes all the extremes (high and low temps, super storms, blizzards, etc) for that period of time.

Climate Change

• Climate change is neither new or unusual.

• The earth’s average surface temperature and climate have been changing throughout the world’s 4.7-billion-year history

- Sometimes gradually (over hundreds to millions of years)

- Other times fairly quickly (over a few decades)

Climate Change• Over the past 900,000

years there have been time periods of cooling and warming.

• For the past 10,000 years we have had the good fortune of a stable climate

Average temperature over past 900,000 Average temperature over past 900,000 yearsyears

Thousands of years agoThousands of years ago900900 800800 700700 600600 500500 400400 300300 200200 100100 PresentPresent

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YearYear18601860 18801880 19001900 19201920 19401940 19601960 19801980 20002000 20202020

13.613.6

13.813.8

14.014.0

14.214.2

14.414.4

14.614.6

14.814.8

15.015.0

The Greenhouse Effect

• For the earth to maintain a constant temperature incoming solar energy must be balanced by an equal amount of outgoing energy.

• Earth’s atmospheric gases, called greenhouse gases, warm the lower atmosphere by absorbing some of the infrared radiation (heat) radiated by the earth’s surface.

The Greenhouse Effect

The Role of the Green House Effect:• Discovered in 1896• With no GHE the earth would be too cold• If the GHE acted by itself the average surface

temperature would be 130o F• Natural cooling takes place by:

• Releasing heat through evaporation• Water vapor molecules rise to the clouds and

release heat into the upper atmosphere• Actual average temperature: 59o F

The Greenhouse EffectPrimary Green House Gases:• Water Vapor: Controlled by the hydrologic cycle• Carbon Dioxide: Controlled by the carbon cycle

Evaluation of ancient glacial ice reveals:• Water vapor levels have been relatively constant

over the past 160,000 years• Carbon dioxide levels have fluctuated• Fluctuations in global carbon dioxide levels

correspond with the fluctuation of the global temperature

The Greenhouse Effect

YearYear

18601860 18801880 19001900 19201920 19401940 19601960 19801980 20002000 20102010

-0.2-0.2

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0.60.6

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1.21.2Observed

Model of greenhouse gases + aerosols + solar output

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http://www.youtube.com/watch?v=Hi3ERes0h84

Climate Change and Human Activities

• Since the Industrial Revolution (1750) there has been a sharp rise in:

1. Use of fossil fuels

2. Deforestation and burning grasslands to raise crops

3. Cultivating rice and using fertilizer that releases N2O

Climate Change and Human Activity

• A typical (500 megawatt) coal plant burns 1.4 million tons of coal each year. There are about 600 U.S. coal plants.

• Coal generates 54% of our electricity.

• Burning coal causes smog, soot, acid rain, and toxic air emissions

Climate Change and Human Activities

• 700 million gasoline burning motor vehicles (555 million of them are cars)

• Emissions from US factories and power plants produce more CO2 than the combination of 146 nations (75% of the world population)

US Carbon Dioxide Emissions by Source

• The combustion of fossil fuels to generate electricity is the largest single source of CO2 emissions in the nation, accounting for about 40% of total U.S. CO2 emissions and 33% of total U.S. greenhouse gas emissions in 2009.

http://www.epa.gov/climatechange/ghgemissions/gases/co2.html

US Carbon Dioxide Emissions by Source• The combustion of

fossil fuels, such as gasoline and diesel to transport people and goods, is the second largest source of CO2 emissions, accounting for about 31% of total U.S. CO2 emissions and 26% of total U.S. greenhouse gas emissions in 2010.

http://www.epa.gov/climatechange/ghgemissions/gases/co2.html

• The production and consumption of mineral products such as cement, the production of metals such as iron and steel, and the production of chemicals accounted for about 14% of total U.S. CO2 emissions and 20% of total U.S. greenhouse gas emissions in 2010.

• Note that many industrial processes also use electricity and therefore indirectly cause the emissions from the electricity production.

US Carbon Dioxide Emissions by Source

http://www.epa.gov/climatechange/ghgemissions/gases/co2.html

U.S. Carbon Dioxide Gas Emissions, 1990-2010

Note: All emission estimates from the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2010.

US Carbon Dioxide Emissions

2008 Global CO2 Emissions from Fossil Fuel Combustion and some Industrial Processes (million metric tons of CO2) • These data

include CO2 emissions from fossil fuel combustion, as well as cement manufacturing and gas flaring. Together, these sources represent a large proportion of total global CO2 emissions

Source: National CO2 Emissions from Fossil-Fuel Burning, Cement Manufacture, and Gas Flaring: 1751-2008.

2008 Global CO2 Emissions from Fossil Fuel Combustion and some Industrial Processes (million metric tons of CO2) • Changes in land use

can be important - global estimates indicate that deforestation can account for 5 billion metric tons of CO2 emissions, or about 16% of emissions from fossil fuel sources. Tropical deforestation in Africa, Asia, and South America are thought to be the largest contributors to emissions from land-use change globally.

Source: National CO2 Emissions from Fossil-Fuel Burning, Cement Manufacture, and Gas Flaring: 1751-2008.

Results of increased CO2 Emissions

• Most climate scientists believe that the increased input of CO2 will…

1. Enhance the earth’s natural greenhouse effect

2. Raise the average global temperature of the atmosphere near the surface of the earth-

“GLOBAL WARMING”

• The following facts are based on analysis of ice cores, The following facts are based on analysis of ice cores, temperature measurements in hundreds of boreholes temperature measurements in hundreds of boreholes into the earths surface and atmospheric temperature into the earths surface and atmospheric temperature measurementsmeasurements

• COCO22 concentrations are at their concentrations are at their highest levelhighest level in the in the

past past 20 million years20 million years

• 75% of human caused CO75% of human caused CO22 emissions are from the emissions are from the

burning of fossil fuelsburning of fossil fuels• The 20The 20thth century is the century is the hottest in the past 1000 yearshottest in the past 1000 years• Since 1861 the global temperature has risen Since 1861 the global temperature has risen 1.11.1o o FF• 10 hottest years10 hottest years on record have occurred since 1990 on record have occurred since 1990

Are we experiencing Global Warming?

http://www.youtube.com/watch?v=ab6jV4VBWZE&feature=related

Evidence of Climate Change

• Melting of land based ice caps and floating ice at the poles and Greenland

• Shrinking of glaciers• Average sea level rise of 4-8” over the past

100 years• Northward migration of some fish, tree and

other species to find an optimal temperature• Early spring arrival and late autumn frosts

• http://www.nbcnews.com/video/nightly-news/48995166#48995166

Evidence of Climate Change

• Glacier National Park

This dramatic comparison between 1920 and 2008 show the incredible mass, thickness and width of the famous Grinnell glacier that has melted due to climate change.

Argentina's Upsala Glacier was once the biggest in South America, but it is now disappearing at a rate of 200 meters per year.

The image is from an 1859 etching of the Rhone glacier in Valais, Switzerland, and shows ice filling the valley. In 2001, the glacier had shrunk by some 2.5km, and its 'snout' had shifted about 450 meters higher up.

• Rising tides• Some scientists predict that a warmer climate will trigger more violent

storms, which will cause increased rates of coastal erosion. This is a section of shoreline at Cape Hatteras in North Carolina in the USA, pictured in 1999 and 2004.

More pestsTree-eating wood beetles are likely to benefit from a warmer climate and reproduce in ever-increasing numbers. These images show damage to White Spruce trees in Alaska caused by the pests.

As the climate warms up, mountainous regions may experience lower levels of snowfall. This image shows Mount Hood in Oregon at the same time in late summer in 1985 and 2002.

http://www.youtube.com/watch?v=eIZTMVNBjc4

Climate Change

Early Warning signs from the Arctic:• The poles are heating faster than the rest of the

earth

• The ice in the Arctic Sea is large enough to cover the USA and is sensitive to air temperatures

• Temperatures in the Arctic have increased much faster than the average global temperature

Climate Change

What will happen if the Arctic Ice Melts?• Greatly amplify warming of the

Arctic region• Reroute warm ocean currents• Could cause significant cooling in

parts of the northern hemisphere• Especially bad cooling in Europe

and Eastern North America• Tundra soil has warmed up so

much that it is releasing more CO2 than it is taking in.

Climate Change

News from Antarctica:• Antarctica has 70% of the

worlds fresh water and 90% of the reflective ice

• Since 1947 the temperatures have increased 10oF in the winter and 4.5oF in the summer.

• Ice the size of Delaware have broken off

• Ice melting off the continent adds to the water volume to raise sea levels

Climate Change

Problems in Greenland:• The worlds largest island (3x the

size of Texas)• If the glaciers melt as they did

110,000-130,000 years ago:1.Average sea levels would rise

13-20 feet2.Massive flooding in the low lying

coastal areas and cities3.Could shut down the Gulf

Stream and North Atlantic Current which keeps Europe warmer than it naturally would be

http://www.youtube.com/watch?v=cqjO8rwB-GI

http://www.youtube.com/watch?v=_Psue0AlIbE

Role of Ice on Global Warming

The Ice Albedo Feedback System:

• As the ice melts the water that results absorbs more heat speeding up the warming process

• The light color of ice reflects 80% of the sunlight, if it melts the ocean will be dark and absorb 80%

Role of Ice on Global Warming

Oceans Moderate the Surface Temperatures:

• Removes 29% of the CO2, but water is less capable of dissolving gas as the temperature increases

• As the temperature increases CO2 will bubble out of the oceans.

• Oceans store heat energy deep in the water and may release it into the atmosphere

• There is a conveyor belt that transfers heat around the world that runs based on differences in water density. Fresh water from melted ice may throw the system off.

http://www.youtube.com/watch?v=Hu_Ga0JYFNg

http://www.youtube.com/watch?v=mDyDmLUxVsE

http://www.youtube.com/watch?v=fvnnRHx5-ug

Climate change and wildlife

Those affected:• Melting ice in the arctic reduces habitat

for polar bears- they need the ice to hunt for food.

• warmer waters can kill coral reefs, which countless marine species depend on for food and shelter

• Droughts caused by changes in rain patterns reduce food supply such as desert grasses and flowering plants for the critically endangered Sonoran pronghorn

Climate Change and Wildlife

• warmer temperatures increase the amount of time pests have to grow and multiply, like the pine bark beetle that is devastating forests all over North America.

• Certain seal species that rarely come to land, such as the harp seal, spotted seal and the ringed seal, depend on Arctic sea ice. Not only does sea ice provide a home for resting, giving birth and raising pups, it is also a feeding ground for some of them. Ice-dependent seal species are likely to have difficulty adapting to ice-free summers

Climate Change and Wildlife• Ivory gulls nest on rocky cliffs and fly

out to the sea ice to fish through cracks in the ice and scavenge on top of the ice. A retreat of sea ice away from the coastal nesting sites would have serious consequences.

• The ice edge in coastal areas is an important feeding ground for the walrus that use the ice as diving platforms to feed on clams on the sea floor. As the ice edge retreats away from the continental shelves to deeper areas, there will be no clams nearby to feed on.

Climate Change and Wildlife

• The vast reduction in multiyear ice in the Arctic Ocean is likely to be immensely disruptive to microscopic life forms associated with the ice, as they will lack a permanent habitat. Research in the Beaufort Sea suggests that ice algae at the base of the marine food web may have already been profoundly affected by warming over the last few decades.

• Results indicate that most of the larger marine algae under the ice at this site died out between the 1970s and the late 1990s, and were replaced by less-productive species of algae usually

associated with freshwater.

Chasing Ice 2

http://abcnews.go.com/International/video/capturing-melting-ice-glaciers-antarctica-22791324

http://www.cbsnews.com/8301-3445_162-57548138/the-scientific-truth-about-climate-change/?tag=showDoorLeadStoriesAreaMain;SunMoLeadHero

• http://www.nbcnews.com/video/nightly-news/50018387#50018387

http://www.youtube.com/watch?v=lgxmOQRn_8c

http://www.youtube.com/watch?v=drINEQFXbPY