1. Global Change Unit 10

2. Global Change
Global change- any chemical, biological or physical property change of the planet. Examples include cold temperatures causing ice ages.
Global climate change- changes in the climate of the Earth.
Global warming- one aspect of climate change, the warming of the oceans, land masses and atmosphere of the Earth.

3. The Greenhouse Effect
When radiation from the sun hits the atmosphere, 1/3 is reflected back.
Some of the UV radiation is absorbed by the ozone layer and strikes the Earth where it is converted into low-energy infrared radiation.
The infrared radiation then goes back toward the atmosphere where it is absorbed by greenhouse gasses that radiate most of it back to the Earth.

4. Greenhouse Gases Water vapor Carbon dioxide Methane Nitrous oxide
Ozone

5. greenhouse gases (the big 5)

6. Natural Greenhouse Gases
Volcanic eruptions- mainly carbon dioxide
Methane – from decomposition
Nitrous oxide- from denitrification
Water vapor

7. Greenhouse Effect
greenhouse effect

8. Anthropogenic Sources GHGs
deforestation (CO2)
fossil fuel combustion (CO2)
cattle digestive gas emissions (methane)

9. Anthropogenic Sources GHGs

10. 900,000 years Average temperature over past 900,000 years 17 16 15 14
Average surface temperature (°C) 13 12 11 10 9
900
800
700
600
500
400
300
200
100
Present
Thousands of years ago
900,000 years

11. Temperature change over past 22,000 years
Agriculture established 1
Average temperature over past
10,000 years = 15°C (59°F) -1
End of
last ice
age
Temperature change (°C) -2 -3 -4 -5
20,000
10,000
2,000
1,000
200
100
Now
Years ago
22,000

12. Temperature change over past 1,000 years Temperature change (°C)
1.0
0.5
Temperature change (°C)
0.0
-0.5
-1.0
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
2101
Year
1000

13. 130 years Average temperature over past 130 years 15.0 14.8 14.6 14.4
Average surface temperature (°C)
14.2
14.0
13.8
13.6
1860
1880
1900
1920
1940
1960
1980
2000
2020
Year
130 years

14. Natural Climate Variation
Natural factors affecting temp?
volcanic eruptions
“wobble” on axis (Milankovitch cycles)
variations in cloud cover
ocean currents
Evidence? ice core data
fossil record of species (plant & animal)

15. Ocean currents distribute energy
Greenland
Antarctica
Ocean currents distribute energy

16. Grab white boards
Take a deep breath….
What gases did you just breathe in???
What % of each?

17. Nitrogen 78%
Oxygen 21%
All rest < 1%
CO2 H2O CO etc…

19. CO2 & temp 380 360 340 320 300 Concentration of carbon dioxide
in the atmosphere (ppm)
280
Carbon dioxide
260
240
+2.5
220
200
Variation of temperature (˚C)
from current level
180
–2.5
–5.0
–7.5
Temperature
change
End of
last ice age
–10.0
160
120 80 40
Thousands of years before present

20. Global Warming

21. albedo Clouds 50–55% Snow 80–90% City 10–15% Forest 5% Grass 15–25%
Bare sand 30–60%
Oceans 5%
albedo

22. Natural and human emissions
simplified climate model
Troposphere
Cooling from increase
CO2 removal by plants and soil organisms
CO2 emissions from land cleaning, fires, and decay
Warming
from
decrease
Aerosols
Heat and
CO2 removal
Heat and
CO2 emissions
Greenhouse
gases
Ice and snow cover
Shallow ocean
Land and soil biotoa
Long-term
storage
Natural and human emissions
Deep ocean

24. permafrost melting
glacier melting

25. Ice & sea level
(glaciers, pack ice, ice caps, fresh water)

26. Pack ice predictions

27. Northwest Passage

28. KMT & thermal expansion

29. Results of warming
Ocean acidification
Coral bleaching

30. Results of warming
Storm Intensity

31. Results of warming
Increased incidence of El Nino
(change in drought, flood patterns)
Dust storms
Forest Fires

32. Results of warming
Change in infectious disease patterns

33. Saltwater intrusion Major irrigation well Well contaminated
with saltwater
Water table
Sea Level
Salt
water
Fresh
groundwater
aquifer
Interface
Interface
Saltwater
Intrusion
Normal
Interface
Saltwater intrusion

34. What can we do?
Reduce deforestation Plant trees Reduce fossil fuel combustion Conserve energy Switch to renewable fuel sources Eat lower on food chain!

35. Global Biodiversity

36. Species Extinction Locally:
Gone where once found, still in other places.
Ecologically:
Too few left to play ecological role
Globally (biologically): Gone. Forever. 36

37. Designations: Endangered species: So few, could soon become extinct.
Threatened species:
Still abundant but is likely to become endangered soon.
Generally K-selected species 37

38. Endangered Species Giant panda Black-footed ferret Whooping crane
Northern spotted owl
Blue whale
Figure 11.3
Endangered natural capital: species that are endangered or threatened with premature extinction largely because of human activities. Almost 30,000 of the world’s species and 1,260 of those in the United States are officially listed as being in danger of becoming extinct. Most biologists believe the actual number of species at risk is much larger.
Mountain gorilla
Florida panther
California condor
Hawksbill sea turtle
Black rhinoceros 38

39. % of species involved in “6th Mass Extinction”39

40. IMPORTANCE OF WILD SPECIES
ecological services
(aka instrumental value)
economic worth
(ecotourism)
inherent right to exist
(intrinsic value) 40

41. HIPPO
causes of premature extinction H I P O 41

42. HIPPO causes of premature extinction
H abitat destruction, degradation, and fragmentation I P O 42

43. HIPPO causes of premature extinction
H abitat destruction, degradation, and fragmentation
I nvasive species P O 43

44. INVASIVE SPECIES Non-native r-selected
Kudzu vine was introduced in the southeastern U.S. to control erosion. It has taken over native species habitats. 44

45. INVASIVE SPECIES
introduced intentionally.
Figure 11-11 45

46. INVASIVE SPECIES
introduced unintentionally.
Figure 11-11 46

47. HIPPO causes of premature extinction
H abitat destruction, degradation, and fragmentation
I nvasive species
P opulation growth of humans P O 47

48. HIPPO causes of premature extinction
H abitat destruction, degradation, and fragmentation
I nvasive species
P opulation growth of humans
P ollution O 48

49. HIPPO causes of premature extinction
H abitat destruction, degradation, and fragmentation
I nvasive species
P opulation growth of humans
P ollution
O verharvest, overconsumption,
overexploitation 49

50. CITES Convention on International Trade of Endangered Species 1975
169 countries
lists 900 species that cannot be commercially traded. 50

51. Endangered Species Act (ESA)
ESA forbids federal agencies (besides defense department) to carry out / fund projects that would jeopardize an endangered species.
ESA : illegal to hunt / kill / collect endangered or threatened species. 51

52. Maintaining species Gene banks, botanical gardens
(raise & store species, often lack funding & storage space)
Zoos & aquariums
preserve individuals for reintroduction
lack of: space, funding, genetic diversity 52

53. AQUATIC BIODIVERSITY Greatest biodiversity coral reefs estuaries
abyssal zone
Provide ecological and economic services. 53

54. Marine Examples Cobia Hogfish Kelp Carrageen Pacific sailfish Moray
Yellow jack
Red snapper
Red algae
Batfish
Bladder kelp
Striped drum
Angelfish
Chinook salmon
Sea lettuce
Orange roughy
Devilfish
Porcupine fish
Great barracuda
Marine Examples
Laminaria
Sockeye salmon
Grouper
Chilean sea bass
Dulse

55. Freshwater Examples Brook trout White waterlily Bluegill White bass
Bulrush
Muskellunge
Rainbow trout
Rainbow darter
Water lettuce
Bowfish
Water hyacinth
Bladderwort
Largemouth black bass
Black crappie
White sturgeon 
Yellow perch
Velvet cichlid
American smelt
Walleyed pike
Eelgrass
Longnose gar
Duckweed
Common piranha
Freshwater Examples
Carp
Egyptian
white lotus
Channel catfish
African lungfish

56. HUMAN IMPACTS approx 20% coral reefs gone
past 100 years sea levels risen cm.
33% mangrove forests destroyed for shipping lanes. 56

57. HIPPO in the ocean
Bio-invaders caused 66% of recent fish extinctions in the U.S.
50% world populations lives near a coast
80% of ocean pollution is from land-based human activities. 57

58. Overfishing 75% fish species overfished -Big fish are becoming scarce
-Smaller fish are next
- 30% of all fish catch is bycatch 58

59. Trawler fishing
Fish farming in cage
Spotter airplane
Sonar
Purse-seine fishing
Trawl flap
Trawl lines
Fish school
Trawl bag
Drift-net fishing
Long line fishing
Float
Buoy
Figure 12.A
Natural capital degradation: major commercial fishing methods used to harvest various marine species. These methods have become so effective that many fish species have become commercially extinct.
Lines with hooks
Deep sea aquaculture cage
Fish caught by gills 59