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THE CARBON CYCLE THE CARBON CYCLE AND AND

GLOBAL WARMINGGLOBAL WARMING

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CARBONCARBON 44THTH most abundant element most abundant element

on Earthon Earth

Essential for life- all Essential for life- all organic (living) compounds organic (living) compounds are composed of carbonare composed of carbon

Found in various formsFound in various forms::- Carbon dioxide (gas)Carbon dioxide (gas)- Limestone (solid)Limestone (solid)- WoodWood- PlasticPlastic- DiamondsDiamonds- GraphiteGraphite- Fossil fuelsFossil fuels

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CARBON CYCLECARBON CYCLE Movement of carbon Movement of carbon

between the atmosphere, between the atmosphere, oceans, biosphere, and oceans, biosphere, and geospheregeosphere

Divided into two Divided into two componentscomponents::

1.1. Geological carbon cycleGeological carbon cycle

2.2. Biological carbon cycleBiological carbon cycle

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GEOLOGICAL CARBON CYCLEGEOLOGICAL CARBON CYCLE Carbonic acid combines Carbonic acid combines

with minerals on the with minerals on the earth’s surface forming earth’s surface forming carbonates (weathering)carbonates (weathering)

Carbonates erode from Carbonates erode from the surface into the the surface into the ocean and settle on the ocean and settle on the ocean floorocean floor

Sinks into the earth, Sinks into the earth, heats up, and eventually heats up, and eventually rises up as carbon rises up as carbon dioxide into the dioxide into the atmosphereatmosphere

* OCCURS OVER MILLIONS OF YEARS

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GEOLOGICAL CARBON CYCLEGEOLOGICAL CARBON CYCLE Carbon dioxide diffuses into Carbon dioxide diffuses into

the ocean forming the ocean forming bicarbonates or bicarbonates or calcium calcium carbonatecarbonate (used to make (used to make shells and other body parts by shells and other body parts by organisms such as coral and organisms such as coral and brachiopod shells)brachiopod shells)

These organisms die and their These organisms die and their shells and body parts become shells and body parts become carbonate-rich depositscarbonate-rich deposits

After a long period of time, After a long period of time, these deposits become these deposits become sedimentary rocks, coal, or oilsedimentary rocks, coal, or oil

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BIOLOGICAL CARBON CYCLEBIOLOGICAL CARBON CYCLE The movement of carbon through the processes of photosynthesis The movement of carbon through the processes of photosynthesis

and cellular respirationand cellular respiration

Also, the consumption of living matter by other organismsAlso, the consumption of living matter by other organisms

The amount of carbon cycled through annually is a 1,000 times The amount of carbon cycled through annually is a 1,000 times greater than the geological carbon cycle componentgreater than the geological carbon cycle component

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PHOTOSYNTHESISPHOTOSYNTHESIS Autotrophs take in carbon dioxide, water, and Autotrophs take in carbon dioxide, water, and

sunlight to produce sugars and oxygensunlight to produce sugars and oxygen

Chemical Formula:6CO2 + 6H2O + light energy → C6H12O6 + 6 O2

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CELLULAR RESPIRATIONCELLULAR RESPIRATION Carbon dioxide is released back into the atmosphere by

breaking down sugar during cellular respiration

Chemical Formula:

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy

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RELEASE OF CARBON DIOXIDERELEASE OF CARBON DIOXIDE

COCO2 2 is also is also released into released into the atmosphere the atmosphere by:by:

1.1. Decaying dead matterDecaying dead matter

2.2. Forest firesForest fires

3.3. VolcanoesVolcanoes

4.4. Burning of fossil fuels Burning of fossil fuels (coal, oil, gas)(coal, oil, gas)

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HUMAN IMPACTHUMAN IMPACT

Since the onset of the industrial revolution, Since the onset of the industrial revolution, burning of fossil fuels and deforestation burning of fossil fuels and deforestation have lead to increase of atmospheric COhave lead to increase of atmospheric CO22

There is strong evidence that supports the There is strong evidence that supports the idea that these activities increase the idea that these activities increase the atmosphere’s ability to hold in heat atmosphere’s ability to hold in heat (greenhouse effect) and is resulting in a (greenhouse effect) and is resulting in a climate change (global warming)climate change (global warming)

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GREENHOUSE EFFECTGREENHOUSE EFFECT Greenhouse effectGreenhouse effect: process : process

by which carbon dioxide and by which carbon dioxide and other gases in the other gases in the atmosphere absorb infrared atmosphere absorb infrared radiation from the sun, radiation from the sun, forming a “heat blanket” forming a “heat blanket” around the Eartharound the Earth

Some sunlight is reflected and Some sunlight is reflected and other is trapped as heat to other is trapped as heat to warm the Earthwarm the Earth

Enhanced greenhouse effect:Enhanced greenhouse effect: caused from an increase of caused from an increase of carbon dioxide, methane, and carbon dioxide, methane, and nitrous oxides from human nitrous oxides from human activities into the air which activities into the air which traps more heat and raises traps more heat and raises the temperatures of the the temperatures of the Earth’s surfaceEarth’s surface

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CLIMATE CHANGECLIMATE CHANGE Global Warming: Global Warming: an an

average increase in the average increase in the Earth's temperature, which in Earth's temperature, which in turn causes changes in turn causes changes in climate.climate.

A warmer Earth may lead to A warmer Earth may lead to changes inchanges in

1.1. rainfall patternsrainfall patterns2.2. A rise in sea levelA rise in sea level3.3. A wide range of impacts on A wide range of impacts on

plants, wildlife, and humansplants, wildlife, and humans

When most scientists talk When most scientists talk about the issue of climate about the issue of climate change, their concern is change, their concern is about global warming caused about global warming caused by human activities. by human activities.

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GLOBAL WARMING DEBATEGLOBAL WARMING DEBATE

POSITION 1POSITION 1- Human pollution is the Human pollution is the

causecause

- Carbon dioxide released Carbon dioxide released into the atmosphere has into the atmosphere has increased by 30% in the increased by 30% in the last 200 yearslast 200 years

- Over the last 100 years, Over the last 100 years, temperatures have temperatures have increased slowly due to an increased slowly due to an increase in greenhouse increase in greenhouse gases (CFC’s, nitrous gases (CFC’s, nitrous oxides, methane, and oxides, methane, and carbon dioxide)carbon dioxide)

POSITION 2POSITION 2- Natural patterns and Natural patterns and

fluctuationsfluctuations

- Nothing to do with human Nothing to do with human activitiesactivities

- Carbon dioxide usage is Carbon dioxide usage is hard to measure (ex. plant hard to measure (ex. plant absorption)absorption)

- Temperatures have Temperatures have increased and decreased increased and decreased in the pastin the past

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READ AND RESPONDREAD AND RESPOND Even with a dramatic cut in global greenhouse Even with a dramatic cut in global greenhouse

emmisions, most scientists predict a temperature emmisions, most scientists predict a temperature rice of about 2C (4.4F) over the next century.rice of about 2C (4.4F) over the next century.

1.1. Think about your daily routines, how would your life be Think about your daily routines, how would your life be different if it were two degrees warmer?different if it were two degrees warmer?

2.2. Think about the foods and products that you consume Think about the foods and products that you consume throughout the year, how would a 2 degree increase throughout the year, how would a 2 degree increase affect their availability?affect their availability?

3.3. Think about the community in which you live, how would Think about the community in which you live, how would a 2 degree increase in the average global temperatures a 2 degree increase in the average global temperatures affect jobs, businesses, and industry in your community?affect jobs, businesses, and industry in your community?