Some of the infrared radiation Some of the infrared radiation passes through the atmosphere, passes through the atmosphere, and some is absorbed and and some is absorbed and re-emitted in all re-emitted in all directions by directions by greenhouse gas greenhouse gas molecules. The molecules. The effect of this effect of this is to warm is to warm the Earth’s the Earth’s surface and surface and the lower the lower atmosphere.atmosphere.
Some solar radiation is reflected by the
Earth and the atmosphere
Solar radiation passes through the clear atmosphere
Most radiation is absorbed by the Earth’s surface and warms it
Infrared radiation is emitted from the Earth’s Surface
The Greenhouse Effect
280
300
320
340
360
380
Carbon Dioxide ConcentrationsMauna Loa
1963 1968 1973 1978 1983 1988 1993
Par
ts p
er m
illi
on
Source: Keeling and Whorf, 1999
1958 1998
Examples of Greenhouse Gases Affected by Human Activities
CO2 CH4 N2O
Pre-industrial concentration 288 ppmv 848 ppbv 285 ppbv
Concentration in 1999 366 ppmv 1800 ppbv 312 ppbv
100 year Global Warming Potential 1 21 310
Atmospheric lifetime (years) 50-200a 12b 120
ppmv = part per million volume; ppbv = part per billion volumea No single lifetime for CO2 can be defined because of the different rates of uptake by different processes.b Defined as an adjustment time which takes into account the indirect effects of methane on its own lifetime.
Sources: IPCC 1995, CDIAC (Manua Loa, Siple Station, Law Dome “DE08”, AGAGE, and Law Dome “BHD” data)
Temperature Change and CO2 Concentrations
CO2 concentration in theatmosphere (Antarctic Ice Core)
Temperature changes compared to the present temperature
Thousands of years ago
Tem
per
atu
re C
han
ge (
o C)
-8-4-2024
150 100 50 0
200
250
300
400
500
600
700
750
CurrentLevel
CurrentLevel
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1880 1900 1920 1940 1960 1980 2000
Global Mean Land and Sea Surface Temperature: 1880-1999
Temperatures expressed relative to 1880-1997 average.Data Source: http://www.ncdc.noaa.gov/ol/climate/research/1998/anomalies/anomalies.html
Tem
per
atu
re C
han
ge (
o C)
Temperature Trends: 1901 to 1998
Red circles reflect warming; Blue circles reflect coolingAll Stations/Trends displayed regardless of statistical significance.Source: National Climatic Data Center/NESDIS/NOAA
Precipitation Trends: 1901 to 1998
Green circles reflect increasing precipitation; Brown circles reflect decreasing precipitationAll Stations/Trends displayed regardless of statistical significance.Source: National Climatic Data Center/NESDIS/NOAA
Projected Temperature
14oC
15oC
16oC
17oC
19oC
18oC
1900 1950 2000 2050 2100
Year
Global average temperature5 year average temperatureIPCC high estimateIPCC best estimateIPCC low estimate
-5 0 5 10 15 20 25
Surface Air Warming: GFDL Model Results for 2xCO2
Source: Manabe and Stouffer, 1994
Degrees (oF)
Surface Air Warming: GFDL Model Results for 4xCO2
Source: Manabe and Stouffer, 1994
-5 0 5 10 15 20 25Degrees (oF)
0 10 20 30 40 50 60
Source: Manabe and Stouffer, 1994
Percent Reduction in Summer Soil Moisture: GFDL Model Results for 2xCO2 and 4xCO2
2xCO2 4xCO2
Percent
0 1 2 3 4 5Thickness (meters)
Changes in March Sea Ice Thickness
Control 4xCO2
Source: Manabe and Stouffer, 1994
Health ImpactsWeather-related MortalityInfectious DiseasesAir Quality-Respiratory Illnesses
Agriculture ImpactsCrop yieldsIrrigation demands
Water Resource ImpactsChanges in water supplyWater qualityIncreased competion for waterImpacts on Coastal AreasErosion of beachesInundate coastal landsCosts to defend coastal communities
Forest ImpactsChange in forest compositionShift geographic rangeof forestsForest Health and Productivity
Species and Natural AreasShift in ecological zonesLoss of habitat and species
Potential Climate Change Impacts
Climate Changes
Sea Level Rise
Temperature
Precipitation
Mediating Process
Health Outcomes
CLIMATECHANGE:TEMPERATURE,PRECIPITATION,AND WEATHER
Ways Climate Change Can Affect Human Health
Thermal extremes (e.g., heatwaves)
Other extreme weather events(floods, storms, etc.)
DISTURBANCES OFECOLOGICAL SYSTEMS
Geographic range and activity of vectors and infective parasites
Altered local ecology of water-borneand food-borne infective agents
Altered food productivity, and associated pests and diseasesSea level rise, population displace-ment, and damage to infrastructure
Levels air pollution, including pollens and spores
INDIRECT
DIRECTChanges in heat- and cold-relatedillnesses and deaths
Deaths, injuries, psychologicaldisorders; damage to public health infrastructure
Geographic ranges and incidence of vector-borne diseases
Regional malnutrition and hunger, impaired child growth and development
Changed incidence of diarrheal andcertain other infectious diseases
Injuries, risks of infectious disease (due to migration, crowding, contaminated drinking water), psychological disordersAsthma and allergic disorders; acute and chronic respiratory disorders and deaths
Source: Adapted from IPCC, 1995.
Days from May to August
0 10 20 30 40 50 60 70 80 100 110 120 130900
1
2
3
4
5
6
7
8
9
10
Sta
nd
ard
ized
Mor
tali
ty
Rat
e p
er 1
00,0
00
Deaths Associated with the July 1966 Heat Wave, New York City
Source: WHO, 1996
0
20
40
60
80
100
Atl
anta
Cin
cin
nat
i
Det
roit
Los
An
gele
s
Min
nea
pol
is
Ph
ilad
elp
hia
San
Fra
nci
sco
Current UKMO GFDL
Dal
las
Ch
icag
o
Kan
sas
Cit
y
Mem
ph
is
New
Yor
k
St.
Lou
is
Probability that 4 Days in June Exceed City’s Temperature Threshold
Source: Probabilities of Temperature Extremes in the U.S.A, Version 1, NCDC, 1999; Kalkstein, 1989
0
150
300
450
600
750
050
100150200250300
0102030405060
050
100150200250300
0
4080
120
160
200
0
250
500
750
1000
1250
1500
Average Annual Excess Weather-Related Mortality for 1993, 2020 and 2050 Climate
GFDL Climate Change Scenario
Los Angeles
New York City
DallasAtlanta
Sources: Kalkstein and Green (1997); Chestnut et al.(1995)
Phoenix
Note: Includes both summer and winter mortality. Assumes full acclimation to changed climate. Includes population growth.
Chicago
1993
2020
2050
Population Likelihood ofat risk Present altered distribution
Disease Vector (millions) Distribution with warming
Malaria mosquito 2400 (sub)tropics Schistosomiasis water snail 600 (sub)tropics Filariasis mosquito 1094 (sub)tropics Onchocerciasis black fly 123 Africa/Latin (river blindness) AmericaAfrican trypano- tsetse fly 55 tropical Africa somiasis(sleeping sickness)Dengue mosquito 2500 (sub)tropics Yellow fever mosquito 450 tropical South
America & Africa
Human Health: Potential Spread of Vector-Borne Diseases
Source: WHO (1996)
- Likely - Very Likely - Highly Likely
Adaptation and Other Health Concerns• Measures to minimize health impacts include:
– improved monitoring, surveillance, and control programs– disaster preparedness and response capability– wider use of protective technologies (sea walls and levees, water purification, vaccination)– public education– early warning systems, improved use of climate forecasts
• Technical solutions may themselves pose health risks– e.g., pesticides to control for insect vectors
• Potential reductions in biodiversity may result in losses of substances that can cure disease or relieve pain
Emissions
• Anthropogenic• Biogenic
Interactions Between Climate Change and Air Quality
Concentrations
Secondary PollutantsAffected by WeatherConditions• Temperature• Precipitation• Windspeed and • Direction
Health Responses
Combined Exposure to Stressful Weatherand Air Pollution
Parameter
Maximum Daily Temperature >= 80oF
Average Daily Wind Speed < 10.5 mph
Precipitation None between 7am and 3pm
Solar Radiation >410 langleys/day
Threshold Value
Source: Kolaz and Swinford, 1990
Meteorological Conditions Present on Ozone Exceedance Days
(Chicago, 1977-1980)
Notes: Present on 81% of ozone exceedance days in the Chicago area. Remaining exceedance days met 3 of 4 criteria.
Health EffectsAcute Respiratory Illnesses and Asthma Aggravation PM, O3, NO2, SO2
Respiratory Hospital Admissions PM, O3
Cardio-Pulmonary Effects (e.g., stroke) CO, PbDevelopment of Chronic Respiratory Disease PM, O3
Cancer Air ToxicsPremature Mortality PM, O3, SO2, PbReproductive Effects Air Toxics
Direct Economic EffectsLost Work Days PM, O3
Decreased Worker Productivity O3
Material Damage & Soiling PM, O3, SO2
Crop Yield Loss O3
Commercial Fishery Harvest Loss Nitrogen DepositionForestry Yield Loss O3
Ecological EffectsAcidic Depostion SO2, NO2
Eutrophication Nitrogen DepositionWetland Preservation Nitrogen Deposition, SO2
Known Adverse Effects of Air Pollutants
Regional 50% Probability Estimates of Sea Level Rise in 2100 and 2200
Portland, ME19 43
New York, NY22 48
Seattle, WA19 42
San Fransisco, CA15 36
Los Angeles13 32
Charleston, SC25 53
Grand Isle, LA55 112
Miami Beach, FL20 44
Source: U.S. EPA (1995).
Estimates are in inches.
U.S. Coastal Lands at Risk from a 20-inch Sea Level Rise in 2100
Source: U.S. EPA (1989).
-1000
0
1000
2000
3000
4000N
orth
east
Mid
-Atl
anti
c
Sout
hA
tlan
tic
S &
WF
lori
da
Lou
isia
na
Res
t of
Gul
fC
oast W
est
Drylands
Wetlands
Sq
uar
e M
iles
Blackwater National Wildlife Refuge (Maryland)
1938
1980N
Trapping Unit
MarshOpen WaterUpland
1 0 1 2 3
Kilometers
Source: U.S. EPA, 1989.
Louisiana: Shoreline Change after a 20-Inch Rise in Sea Level
Lake CharlesLafayette
Baton Rouge
Morgan City
Houma
NewOrleans
Gulf of Mexico
Land Lost
Water Resources: Regional Vulnerability
Source: U.S. EPA (1989)
UseUsePacificPacific
NorthwestNorthwest CaliforniaCalifornia
AridAridWesternWestern
RiverRiverBasinsBasins
GreatGreatPlainsPlains
GreatGreatLakesLakes MississippiMississippi
South-South-easteast
North-North-easteast
Irrigation
Thermal power
Industrial
Municipal/ domestic
Water quality
Navigation
Flood control
Hydropower
Recreation
Changes in Agricultural Yields 2.5oF Warming; 7% Increase in Precipitation; 530 ppmv CO2
Change in Wheat Yield Change in Corn Yield
Percent Change
-30 -20 -10 0 +30 >+30+20+10
Source: Rosenzweig, 1995
Agricultural Resources: Potential Change inGrain Yield due to Doubled CO2
Based on GISS model; physiological CO2 effects included
Source: Rosenzweig and Hillel (1993)
-30% 10%-10%Percent of Change in Yield
30%
-100
0
100
200
300
400
Agricultural Resources: Increase in Global Population at Risk from Hunger
Without Adaptation With Adaptation
Change in Number of People at Risk of Hunger
Source: Strzepak and Smith (1995)
Mill
ion
s GISS
GFDLUKMO
Current Climate
OSU Climate
UKMO Climate
Conifer ForestBroadleaf ForestSavanna/WoodlandShrub/WoodlandGrasslandArid Lands
Change in PotentialVegetation for 2050Climate Scenario
Source: Neilson, 1995
Current and Projected Ranges of Sugar Maple
Source: Redrawn from Davis and Zabinski, 1992
Present Range Overlap Predicted Range
Prediction based on increased temperature
Prediction based on increased temperature and moisture reduction
Loss of Habitat for Brown Trout from a Doubling of CO2 - 2050
Not includedin analysis *
1-49% Loss 50-100% Loss
Source: EPA, 1995 GFDL Climate Change Scenario
* Dual screening criteria used for inclusion: 1) Thermal modeling predicts suitability and 2) Fish presence in 10% or more of State’s water bodies.
Low Density
Medium Density
High Density
Source: Schneider and Root, 1997.
Bobolink Bird Distribution
IPCC Second Assessment
• Climate has changed over the past century– Global mean surface air temperature has increased .5-1o F– Global sea level has risen 4-10 inches– Global precipitation over land has increased 1%
• “The balance of evidence suggests a discernible human influence on global climate” (IPCC, 1995)
• Climate is expected to continue to change in the future– Projected temperature increase of 3.6oF by 2100 (1.8-6.3oF)– Projected sea level rise of 20 inches by 2100 (6-38 inches)– Likely increase in precipitation intensity
IPCC Second Assessment Report Conclusions
There are still many uncertainties
• Future emissions, biogeochemical cycling of GHGs and aerosols, and future concentrations
• Representation of climate feedback processes in models– clouds, convection and precipitation, sea ice, vegetation,
oceans
• Detection and attribution
• Non-linear responses (“Surprises”) and severe storms
• Regional patterns of change