Climate and Global Change Notes 29-1 Climate & Global Change The Earth’s Carbon Cycle Carbon Budget Carbon Change Rain Forest Biodiversity Human Activities

Climate and Global Change Notes

29-1

Climate & Global Change

The Earth’s Carbon Cycle

Carbon BudgetCarbon Change

Rain ForestBiodiversity

Human ActivitiesBurning Cycles

Natural ChangesDesertification

SahelDeforestation

Science Concepts

Feedbacks

Photosynthesis

The Earth System (Kump, Kastin & Crane)

• Chap. 8 (pp. 165-167)


29-2

The Carbon Cycle

CarbonBudget

Intermediate and Deep Waters38000 + 2/year

0.2

4 5 37

3640Biota 3

Surface Ocean 1000 + 1/yearRivers0.8

Land Biota550

Atmosphere 750 + 3/year

9050 501025

Fossil Fuel

2

Deforestation

92

Sedimentation

Soil and Detritus1500

50


29-3

The Carbon Cycle

OceanCarbonBudget


29-4

The Carbon Cycle

Carbon Change

• The largest human contribution to climate change

• Human activity adds CO2 to the atmosphere

- Fossil fuels - biomass burning - cement production

• Carbon dioxide naturally cycles among the land, atmosphere and oceans

• Knowledge of the carbon cycle is essential to forecasting human influences on climate

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

http://www.windows.ucar.edu/tour/link=/earth/climate/images/carboncycle_jpg_image.html


29-5

The Carbon Cycle

Net Primary Productivity

• Amount of carbon consumed by plants (both on land and in the ocean) per

square kilometer, called net primary productivity, in 2002

• Note: Rain-forest areas are regions of high carbon consumptions

http://earthobservatory.nasa.gov/ Study/LBA/escape.html


29-6

The Carbon Cycle

Rainforests

• Where are they?Area of Closed

Country Forest in 1985 (Hectares)Brazil 357,480,000Indonesia 113,895,000Zaire 105,750,000Peru 69,680,000India 51,841,000Colombia 46,400,000Mexico 46,250,000Bolivia 44,010,000Papua New Guinea 34,230,000Burma 31,941,000Venezuela 31,870,000Congo 21,340,000Malaysia 20,995,000Gabon 20,500,000Guyana 18,475,000Cameroon 17,920,000Suriname 14,830,000Ecuador 14,250,000Madagascar 10,300,000


29-7

The Carbon Cycle

Rainforests (Con’t)

• Biodiversity Importance

- Bushmaster snake (lives in the rainforest) venom used as a

pattern to make hypertension medicine.

- As of 1985, 119 pure chemical substances extracted from

higher plants were used in medicine. Therapeutic

Plant Drug CategoryFoxglove Digitoxin Cardiotonix

Opium poppy Codeine AnalgesicMorphine SedativeTobacco Nicotine InsecticideMay apple Podophyllotoxin Cancer

White willow Salicin Analgesic(Asperin - known to Hippocrates)

Cocoa, Cacoa Theobromine DiureticCurare Tubocurarine Skeletal muscle relaxant

(Arrow poison)Pacific yew Toxal Ovarian Cancer

(4-6 trees to treat 1 woman)(~200,000 trees exist)(20,000 cases per year)


29-8

The Carbon Cycle

South AmericanBurning Cycles

• 1998 firesJan - Dec

• Note - Aug/Sept/Oct max for central and southern regions

• Note - Feb/Marmax fornorthern area


29-9

South AmericanBurning Cycles (Con’t)

The Carbon Cycle


29-10

African Burning Cycles• 1998 fires Jan - Dec • Dec/Jan max through central Africa, Jun/Jul max farther south

The Carbon Cycle


29-11

Desertification

90°N 60°N 30°N 0° 30°S 60°S 90°S

0

-500

500

1000

1500

2000

Latitude

Rainfall Evaporation

Runoff

Millimeters per year

http://earthobservatory.nasa.gov/

Study/Desertification/

desertification.html?

June 2005

Sahel

• Sahel stretches across Africa, roughly 15° north of Equator

• Satellite measurements of vegetation reveal it as a transition zone between sands of the Sahara and jungles of the Congo in heart of Africa


29-12

Desertification

Sahel (Con’t)

• CollapseN

N/2

1920 1960 2000 2040Year

Cattle, Camels, & Goats (N = 600,000)

Population (N = 150,000)

Soil Condition: Grams of vegetation per 10,000 m2

(N = 450)



http://earthobservatory.nasa.gov/Study/Desertification/desertification2.html


29-13

Desertification

Sahel (Con’t)

• MODIS

- Albedo

0.00

0.10

0.20

0.50Albedo

0.40

0.30

0.05

0.15

0.25

0.35

0.45





29-14

Desertification

Sahel (Con’t)

• Change

QuickTime™ and aH.264 decompressor




29-15

Desertification

Sahel (Con’t)

• 2003 data spatially averaged over area 8.5ºW–8.5ºE and 12.5º–15.5ºN

• Monthly mean precipitation in millimeters per day (blue)

• Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) (green)

• Broadband surface albedo (red)

QuickTime™ and aTIFF (LZW) decompressor


http://www.agu.org/journals/eo/eo0703/2007EO030002.pdf#anchorEos, Vol. 88, No. 3, 16 January 2007


29-16

Desertification

Sahel (Con’t)

• 1984 and 2003 latitudinal profile of total June to October (JJASO) precipitation

• 1984 and 2003 mean August to October (ASO) broadband surface albedo averaged between18ºW and 20ºE

http://www.agu.org/journals/eo/eo0703/2007EO030002.pdf#anchorEos, Vol. 88, No. 3, 16 January 2007

QuickTime™ and aTIFF (LZW) decompressor



29-17

Brazilian Rainforests

1975 1986

Deforestation


29-18

Rondonia, Brazil

1973 1978 1983

Deforestation


29-19

Guatemala

Deforestation


29-20

Guatemala

• 1986 to 1997

• Red is forest; Greens are roads and cleared land

• Area of picture about 40% size of New Jersey

1986 - Peten, Guatemala

Deforestation

1997 - Peten, Guatemala


29-21

Facts

• Equivalent of ten city blocks of rainforest is destroyed every minute, that an area the size of Pennsylvania lost every year

• 7% of the Earth's dry land surface is rainforest, home to more than 50% of the world's plants and animals

• A bulldozer must remove 60 rainforest trees to reach one mahogany tree

• There are 100 different species of large trees in a single acre of rainforest

Deforestation


29-22

Facts

• Estimate rate of deforestation

Deforestation


29-23

System Dynamics

The Earth System (Kump, Kastin & Crane)

• Chap. 2 (pp. 18-20)• Chap. 14 (pp. 279-280


29-24

System Dynamics

Positive Feedback

• Desertification - Sahel

• Ice - Albedo feedback

Negative Feedback

• CO2 - Cloud - Albedo feedback

• CO2 - Plankton feedback

Documents

Climate and Global Change Notes 29-1 Climate & Global Change The Earth’s Carbon Cycle Carbon Budget Carbon Change Rain Forest Biodiversity Human Activities