SLIDE 1 The University of the West Indies Organization of American States
PROFESSIONAL DEVELOPMENT PROGRAMME: COASTAL INFRASTRUCTURE DESIGN, CONSTRUCTION AND MAINTENANCE
A COURSE IN COASTAL ZONE/ISLAND SYSTEMS MANAGEMENT
CHAPTER 8 (AS PRESENTED AT THE WORKSHOP)
CLIMATE CHANGE
By ANDREW GARCIA, PhD
Coastal Hydraulic Laboratory, US Army Corps of Engineers Vicksbury, MA, USA
Organized by Department of Civil Engineering, The University of the West Indies, in conjunction with Old Dominion University, Norfolk, VA, USA and Coastal Engineering Research Centre, US Army, Corps of Engineers, Vicksburg, MS , USA.
Antigua, West Indies, June 18-22, 2001
SLIDE 2
Introduction to Climate Change
US Army Engineer Research and Development Center
SLIDE 3 Course Outline
Part I. Indicators of climate change Proposed sources of climate change Attribution of climate change Part II. Effects of climate change Part III. El Nino and tropical cyclones
SLIDE 4 Principle Material Sources
Intergovernmental Panel on Climate Change, Reports of Working Groups I and II Bulletin and journals of the American Meteorological Society NASA reports on Greenland ice cap (Krabill, et al.) and satellite derived atmospheric temperatures (Spencer and Christy) Various text books
SLIDE 5 Introduction to Climate Change
Climate Change Definition… A measurable long-term change in an atmospheric or oceanic physical or chemical variable attributable to natural
SLIDE 6 Climate Change Indicators
- For the period 1901 – 2000, earth’s surface
temperature (land and ocean) has increased 0.6 ± 0.2°C
- For the Northern Hemisphere, 1990’s was the
warmest decade and 1998 was the warmest year
- For the Northern Hemisphere, there was ~ 10%
decrease in snow cover since the late 1960’s
(Continued)
SLIDE 7 Climate Change Indicators
(Concluded)
- There has been an overall retreat of mountain
glaciers in non-polar regions this century
- El Nino (warm episodes) have been more
frequent, persistent, and intense since the 1970’s when compared with the previous one-hundred years
SLIDE 8
Earth’s Surface Temperature
SLIDE 9
Surface Temperature - 2
SLIDE 10
Temperature by Hemisphere
SLIDE 11
NH Proxy Temperature
SLIDE 12
Northern Hemisphere Temperature
SLIDE 13
Greenland Ice Cap
SLIDE 14
NASA Airborne LASER
SLIDE 15
NASA LASER Close-up
SLIDE 16
Ice Accumulation - Loss
SLIDE 17
Southern Greenland
SLIDE 18
Southeast Greenland
SLIDE 19
Greenland Close-up
SLIDE 20 Absent Indicators of Climate Change
- Southern Hemisphere oceans and parts of
Antarctica have not shown discernable warming
- No significant trend observed in the extent of
Antarctic sea ice since 1978 using satellite
(Continued)
SLIDE 21 Absent Indicators of Climate Change
(Concluded)
- No discernable trend in tropical or extra-tropical
storm activity
- No systematic changes in the frequency of
tornadoes, hail events, or severe thunderstorms
SLIDE 22 Attributed Sources of Atmospheric Warming re 1750
“Greenhouse” gases…
- Carbon dioxide (CO2) – 31%
- Nitrous oxide (N2O) – 17%
- Methane (CH4) – 151%
SLIDE 23
Greenhouse Gas Growth
SLIDE 24
Nitrous Oxide Increase
SLIDE 25
Carbon Dioxide Increase
SLIDE 26
Methane Increase
SLIDE 27
Sulfate Aerosols in Greenland Ice
SLIDE 28 What is the “Greenhouse” effect?
- 1. Incoming solar radiation is strongest in the visible and
near UV wavelengths.
- 2. Outgoing terrestrial radiation is strongest in the IR
wavelengths.
- 3. “Greenhouse gases” (including water vapor) absorb
- utgoing IR radiation thereby trapping energy.
SLIDE 29
Incoming Solar Spectrum
SLIDE 30
Idealized Outgoing Spectrum
SLIDE 31
Atmospheric Absorption Spectrum
SLIDE 32 Anthropogenic Sources of “Greenhouse” Gases
- Carbon dioxide – burning of fossil fuels,
deforestation
- Nitrous oxide – use of chemical fertilizers,
animal feedlots, chemical industries
- Methane – burning of fossil fuels, rice
agriculture, deforestation (termites)
SLIDE 33
Simulated Surface Temperature, Natural
SLIDE 34
Simulated Surface Temperature, Anthropogenic
SLIDE 35
Simulated Surface Temperature, Combined
SLIDE 36
Total Radiative Forcing
SLIDE 37
Atmospheric Temperature Trend, Troposphere
SLIDE 38
Atmospheric Temperature Trend, Stratosphere
SLIDE 39
Big Picture
SLIDE 40 Summary on Detection and Attribution
Recent changes in global climate inferred from near-surface atmospheric temperatures cannot be readily explained by natural climate variability. Greenhouse warming alone is insufficient to explain the observed climate change pattern.
Barnett et al., BAMS, 1999 (continued)
SLIDE 41 Summary on Detection and Attribution
The most probable cause of observed warming is a combination of internally and externally forced natural variability and anthropomorphic sources.
Barnett et al., BAMS, 1999 (concluded)
SLIDE 42 Natural Systems at Risk Include -
- Glaciers
- Coral-reefs and atolls
- Mangrove swamps
- Tropical and boreal forests
- Prairie wetlands
SLIDE 43 Human Systems Sensitive to Change Include -
- Water resources
- Agriculture and forestry
- Coastal zones and marine fisheries
- Human health
- Insurance and financial services
SLIDE 44 Possible Adverse Affects Include -
- Reduction in potential crop yields, particularly in
tropical and sub-tropical regions
- Decreased water availability in present water scarce
regions, particularly in the sub-tropics
- Increased flooding risk from both more frequent
heavy precipitation events and sea-level rise
(Continued)
SLIDE 45 Possible Adverse Affects Include -
(Concluded)
- Increased energy demand for summertime
cooling
- Increased geographic range of vector-borne
infections
SLIDE 46 Possible Beneficial Effects Include -
- Increased potential crop yields in some mid-latitude
regions
- Increased potential global timber supply from
appropriately managed forests
- Increased water availability in some present water-
scarce regions, e.g., parts of southeast Asia
(Continued)
SLIDE 47 Possible Beneficial Effects Include -
(Concluded)
- Reduced human mortality in mid- and high
latitudes
- Reduced wintertime demand for heating
SLIDE 48 Observed Climate Trends in Caribbean Islands
- Mean annual temperature increase of >0.5°C
during the period 1900-1995*
- Mean annual precipitation increase of
~250mm*
* Based upon data obtained in Cuba?
SLIDE 49 Predicted Climate Change for Island Basins
- Inter-model agreement on climatic effects of
CO2 doubling is poor for the Western Atlantic, Caribbean and Mediterranean Seas
- There appears to be no clear trend as to
frequency, intensity, or distribution of topical cyclones in these basins
SLIDE 50
El Nino Region Definition
SLIDE 51
El Nino and Hurricane Seasons
SLIDE 52
El Nino Damage Estimates
SLIDE 53 El Nino, La Nina, and Atlantic Hurricanes
- La Nina episode means a greater frequency of
damaging storms and more damage per storm
- El Nino episode does not mean no hurricanes, as
several El Nino years have seen large effects
- Mid-Pacific equatorial SST anomaly can provide a
statistically significant indicator of damage
(Continued)
SLIDE 54 El Nino, La Nina, and Atlantic Hurricanes
(Concluded)
- Mid-Pacific equatorial SST anomaly is not the only
climate factor related to hurricane damage
- There appears to be no skill in forecasting Nino SST
anomalies other than simple climatology and persistence, which is good only to 8 months
SLIDE 55 Conditions for Tropical Cyclone Formation
- 1. Warm ocean surface waters, ~26 degrees C, of sufficient
depth, ~50m.
- 2. Conditionally unstable atmosphere, one that cools with
height.
- 3. Sufficient atmospheric moisture at lower-levels, ~5km.
(continued)
SLIDE 56 Conditions for Tropical Cyclone Formation
- 4. At least ~5 degrees distance from the equator; sufficient
Coriolis force to produce gradient wind balance to maintain low surface pressure.
- 5. An initiating disturbance, e.g., tropical wave.
- 6. Low vertical wind shear between the surface and upper
troposphere. (concluded)
SLIDE 57
Hurricane Processes,I
SLIDE 58
Hurricane Processes, II
SLIDE 59
Hurricane Processes, III
SLIDE 60
Hurricane Probability
SLIDE 61
Intense Hurricane Probability
SLIDE 62 Closing Quote
“Models are what we use when we don’t have data.”
