teaching climate change epo special interest group aileen o’donoghue priest associate professor of...
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Teaching Climate ChangeTeaching Climate ChangeEPO Special Interest GroupEPO Special Interest Group
Aileen O’DonoghueAileen O’DonoghuePriest Associate Professor of Physics
St. Lawrence University, Canton, NYPriest Associate Professor of Physics
St. Lawrence University, Canton, NY
Emphases for the PublicEmphases for the Public Earth Will Be FINE!
it’s been much hotter and much colder the 6.8 billion people won’t be fine
nor will the polar bears, pikas, and other megafauna
What we know: Data & Theories Not NEW!
“amplified warming” since 1850 (John Tyndall)
Data carefully collected & analyzed for decades requires careful study
understanding before dismissal!
How we know it: Process of science peer review: trying to insure honesty, not
orthodoxy
Earth Will Be FINE! it’s been much hotter and much colder the 6.8 billion people won’t be fine
nor will the polar bears, pikas, and other megafauna
What we know: Data & Theories Not NEW!
“amplified warming” since 1850 (John Tyndall)
Data carefully collected & analyzed for decades requires careful study
understanding before dismissal!
How we know it: Process of science peer review: trying to insure honesty, not
orthodoxy
What do we knowWhat do we know Past climates
how do we know of past climates? Variations in climate
how does climate vary naturally? Predicting the future
how do we model inputs & feedbacks?
IPCC UCC Skeptics
Past climates how do we know of past climates?
Variations in climate how does climate vary naturally?
Predicting the future how do we model inputs &
feedbacks? IPCC UCC Skeptics
Past Climate RecordsPast Climate Records Instrumental
18th – 21st centuries with increasing accuracy Best in Europe, N. America, Australia Very little data over oceans, 70% of surface
Keeling Curve: 1957 - present CO2 in air over Mauna Loa, Hawaii
Instrumental 18th – 21st centuries with increasing accuracy
Best in Europe, N. America, Australia Very little data over oceans, 70% of surface
Keeling Curve: 1957 - present CO2 in air over Mauna Loa, Hawaii
Northern Summer: Plants absorb CO2
Northern Winter: CO2 builds up from decay.
Past Climate RecordsPast Climate Records Proxy (indirect natural) Records
Tree rings Temperature, precipitation, fire, insects, etc. Depends on area, species level of stress
best near stress limit
Back to ~1000 years (bristlecone pine in CA) plus overlapping with structures
Proxy (indirect natural) Records Tree rings
Temperature, precipitation, fire, insects, etc. Depends on area, species level of stress
best near stress limit
Back to ~1000 years (bristlecone pine in CA) plus overlapping with structures
Past ClimatesPast Climates Proxy (indirect natural) Records
Palynology (pollen) from sediments Accumulated in peat bogs & lakes Must be independently dated (cross-matched or
12C) Local influences complicate records
eg. Fire, flood, etc.
Types of pollen vary in uniqueness eg. Pine pollen everywhere … even ice caps!
Proxy (indirect natural) Records Palynology (pollen) from sediments
Accumulated in peat bogs & lakes Must be independently dated (cross-matched or
12C) Local influences complicate records
eg. Fire, flood, etc.
Types of pollen vary in uniqueness eg. Pine pollen everywhere … even ice caps!birchbirch
sprucespruce
shrubshrub
PinePinesedgesedge
oakoak
Past ClimatesPast Climates Vostok, Antarctica & Greenland Ice
Cores Vostok, Antarctica & Greenland Ice
CoresGreenland Ice Core Summers indicated by
arrows.
Greenland Ice Core Summers indicated by
arrows.
Past ClimatesPast Climates Vostok, Antarctica & Greenland Ice
Cores Show annual* variations of atmosphere
Bubbles of air contain old atmosphere Variations in CO2, CH4 Give
Comparisons to today, Correlations with temperature
Ice crystals vary in composition Different Isotopes of Oxygen, Hydrogen, etc.
Dust Volcanos, Impacts, Winds, Organic Matter
Vostok, Antarctica & Greenland Ice Cores Show annual* variations of atmosphere
Bubbles of air contain old atmosphere Variations in CO2, CH4 Give
Comparisons to today, Correlations with temperature
Ice crystals vary in composition Different Isotopes of Oxygen, Hydrogen, etc.
Dust Volcanos, Impacts, Winds, Organic Matter
*Where annual layers unclear, chronology is reconstructed from other annual variables*Where annual layers unclear, chronology is reconstructed from other annual variables
IsotopesIsotopes Number of neutrons in nuclei varies
eg. Oxygen 16 (16O) & 18 (18O)
18O heavier than 16O harder to evaporate Ice Cores
High ratio of 18O/16O for warm globe
Deep Sea Sediments High ratio of 18O/16O for cool globe
Number of neutrons in nuclei varies eg. Oxygen 16 (16O) & 18 (18O)
18O heavier than 16O harder to evaporate Ice Cores
High ratio of 18O/16O for warm globe
Deep Sea Sediments High ratio of 18O/16O for cool globe
18O18O16O16O8 protons
8 neutrons
8 protons 8
neutrons
8 protons 10
neutrons
8 protons 10
neutronsOn average: 1 18O for 1000
16O
On average: 1 18O for 1000
16O
IsotopesIsotopes Variations indicate temperature
Higher 18O/16O in ice warmer Lower 18O/16O in ice cooler
Variations indicate temperature Higher 18O/16O in ice warmer Lower 18O/16O in ice cooler
2H/1H2H/1H
18O/16O18O/16O
Arctic & Antarctic show same variations
variations are global
Arctic & Antarctic show same variations
variations are global
Sea Temp. Higher 18O/16O
cooler Lower 18O/16O
warmer
Sea Temp. Higher 18O/16O
cooler Lower 18O/16O
warmer
C. R. W. Ellison et al., Science 312, 1929 -1932
(2006)
C. R. W. Ellison et al., Science 312, 1929 -1932
(2006)
Sea surface temperatureSea surface temperature
18O/16O18O/16O
IsotopesIsotopes
IsotopesIsotopes Variations track
with GH gases Variations track
with GH gases
2H/1H2H/1H
2H/1H2H/1H
Methane
Carbon Dioxide
www.realclimate.org/index.php?p=221
now then
Temperature & GH GasesTemperature & GH Gases
Ice Core Contributions to Global Change Research: Past Successes and Future Directions
National Ice Core Laboratory Ice Core Working Group, May, 1998.
Carbon Dioxide
Methane
Temp (°C)
Temperature tracks with
gases …
Which drives which?
Temperature tracks with
gases …
Which drives which?
now then
Global CO2Global CO2
CO2 from Ice Cores & Mauna Loa
CO2 from Ice Cores & Mauna Loa
IsotopesIsotopes Necessary to understand ice core data!
Allows reconstruction of temperature Only way to get to last curve!
Respects the audience Demands they respect the science
Necessary to understand ice core data! Allows reconstruction of temperature Only way to get to last curve!
Respects the audience Demands they respect the science
Discussion: How much should we simplify?
Discussion: How much should we simplify?
Modeling the ClimateModeling the Climate Climate Systems
Sun – source of (almost) all energy Atmosphere – changes over hours Oceans – surface changes over weeks – depths change over millennia Biosphere – changes annually to centuries Cryosphere – ice, glaciers permafrost, snow – various change scales Geosphere – volcanos, continental drif – long time scales, large changes
Climate Systems Sun – source of (almost) all energy Atmosphere – changes over hours Oceans – surface changes over weeks – depths change over millennia Biosphere – changes annually to centuries Cryosphere – ice, glaciers permafrost, snow – various change scales Geosphere – volcanos, continental drif – long time scales, large changes
Modeling the ClimateModeling the Climate Systems & Feedbacks Among
Radiation, Surface and Atmosphere (CO2) insolation (incoming sunlight varies) reflection, absorption, re-radiation by surface, air
Water cycle evaporation, precipitation, runoff
Land surface soil moisture, vegetation, topography, snow & ice
Ocean surface currents, deep currents, chemistry
(salinity) Sea Ice
strongly affected by feedbacks
Systems & Feedbacks Among Radiation, Surface and Atmosphere (CO2)
insolation (incoming sunlight varies) reflection, absorption, re-radiation by surface, air
Water cycle evaporation, precipitation, runoff
Land surface soil moisture, vegetation, topography, snow & ice
Ocean surface currents, deep currents, chemistry
(salinity) Sea Ice
strongly affected by feedbacks
Carbon DioxideCarbon Dioxide Long-term sources: Volcanoes & Humans Long-term sinks: Chemical Weathering
H2O + CO2 H2CO3 H+ + HCO3
CaCO3 + H+ Ca + HCO3
Variable storage: Biosphere plants absorb CO2 to grow
trees make wood out of air! plants make us … we’re made of air!
decay releases CO2
Long-term sources: Volcanoes & Humans Long-term sinks: Chemical Weathering
H2O + CO2 H2CO3 H+ + HCO3
CaCO3 + H+ Ca + HCO3
Variable storage: Biosphere plants absorb CO2 to grow
trees make wood out of air! plants make us … we’re made of air!
decay releases CO2
Carbonic AcidCarbonic Acid Bicarbonate can combine with many compounds eg.
NaHCO3, Ca(HCO3)2
Bicarbonate can combine with many compounds eg.
NaHCO3, Ca(HCO3)2
FeedbacksFeedbacks Greenhouse Effect: Warming
Good … makes Earth inhabitable!! Ground absorbs sunlight Ground heats (parking lots in summer) Ground radiates heat (Infrared, IR) Atmosphere absorbs (some) IR Atmosphere heats
Greenhouse Effect: Warming Good … makes Earth inhabitable!! Ground absorbs sunlight Ground heats (parking lots in summer) Ground radiates heat (Infrared, IR) Atmosphere absorbs (some) IR Atmosphere heats
Greenhouse Effect Concept Inventory
Greenhouse Effect Concept Inventory
Dr. John Keller, Cal Poly Poster C24
Dr. John Keller, Cal Poly Poster C24
FeedbacksFeedbacks Feedback Mechanism: Evaporation
Clouds shade surface, cool it, warming stops?
H2O vapor absorbs more IR, more warming
Runaway Greenhouse … Venus!
Feedback Mechanism: Plant Growth More CO2 increases plant growth
More plant growth is good!!
Plants absorb CO2 (Keeling curve annual cycles)
CO2 is Reduced
BUT … why isn’t it working yet?
Feedback Mechanism: Evaporation Clouds shade surface, cool it, warming
stops? H2O vapor absorbs more IR, more warming
Runaway Greenhouse … Venus!
Feedback Mechanism: Plant Growth More CO2 increases plant growth
More plant growth is good!!
Plants absorb CO2 (Keeling curve annual cycles)
CO2 is Reduced
BUT … why isn’t it working yet?
www.co2science.org
FeedbacksFeedbacks Feedback Mechanism: Ice-Albedo Effect
Warming melts glaciers, sea ice Ground warms more than snow/ice Ground warms, radiates more IR Atmosphere warms More ice melts
Feedback Mechanism: Evaporation More clouds & cooling, snow comes back
Warming halted
H2O vapor absorbs more IR, more warming “Hot House Earth”
Feedback Mechanism: Ice-Albedo Effect Warming melts glaciers, sea ice Ground warms more than snow/ice Ground warms, radiates more IR Atmosphere warms More ice melts
Feedback Mechanism: Evaporation More clouds & cooling, snow comes back
Warming halted
H2O vapor absorbs more IR, more warming “Hot House Earth”
Climate VariationsClimate Variations Due to
Atmospheric variations Pacific Cycles
El Niño Soutern Oscillation (ENSO) Pacific Decadal Oscillation
Atlantic Cycles North Atlantic Oscillation Atlantic Multidecadal Oscillation
Due to Atmospheric variations
Pacific Cycles El Niño Soutern Oscillation (ENSO) Pacific Decadal Oscillation
Atlantic Cycles North Atlantic Oscillation Atlantic Multidecadal Oscillation
Variations in the AtmosphereVariations in the Atmosphere NAO Negative Phase mid 1950’s - 1970 NAO Negative Phase mid 1950’s - 1970
It WAS colder
when we were kids!
It WAS colder
when we were kids!
Variations in the AtmosphereVariations in the Atmosphere NAO Mostly positive since mid-70’s NAO Mostly positive since mid-70’s
Skeptics use
cooling of eastern
Canada to dispute global
warming
Variations in the AtmosphereVariations in the Atmosphere Atlantic Multidecadal Oscillation (AMO)
Sea Surface Temperature in North Atlantic
Atlantic Multidecadal Oscillation (AMO) Sea Surface Temperature in North Atlantic
AMO Correlates with numbers of major hurricanes
… and southwestern droughts!
AMO Correlates with numbers of major hurricanes
… and southwestern droughts!
Variations in the AtmosphereVariations in the Atmosphere
Not perfect correlation …
what else is going on?
Drought Correlation with PDO and AMO
Drought Correlation with PDO and AMO
Variations in the AtmosphereVariations in the Atmosphere
Droughts more severe
& widespread
when AMO is positive
Droughts more severe
& widespread
when AMO is positive
oceanword.tamu. edu
Current Conditions
Current Conditions
Variations in the AtmosphereVariations in the Atmosphere
Insolation Variations Solar brightness variations
sunspots & other stellar variations
Earth orbital variations (Milankovitch) other planets’ gravity vary Earth’s orbit
Solar system environmental variation Sun moves through galactic environment
Insolation Variations Solar brightness variations
sunspots & other stellar variations
Earth orbital variations (Milankovitch) other planets’ gravity vary Earth’s orbit
Solar system environmental variation Sun moves through galactic environment
InsolationInsolation Varies with Milankovitch Cycles
Last million years for 65 N (Berger (1991))
Varies with Milankovitch Cycles Last million years for 65 N (Berger (1991))
9,000 years ago, ice age ended!9,000 years ago, ice age ended!
Some argue this is the cause of ALL climate change … so we can ignore our
CO2
Some argue this is the cause of ALL climate change … so we can ignore our
CO2
Milankovitch and TemperaturesMilankovitch and Temperatures
Vostok Core DataVostok Core Data
Milankovitch InsolationMilankovitch Insolation
Temperature from 18O/16OTemperature from 18O/16O
Connection apparent … but can it explain current
warming?
Connection apparent … but can it explain current
warming?
IPCCIPCC Intergovernmental Panel on Climate
Change Established in 1988
World Meteorological Org. (WMO) UN Environment Programme (UNEP)
Mandate
Intergovernmental Panel on Climate Change Established in 1988
World Meteorological Org. (WMO) UN Environment Programme (UNEP)
Mandate“The role of the IPCC is to assess on a comprehensive, objective, open and
transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of
human-induced climate change, its potential impacts and options for adaptation and
mitigation.”
“The role of the IPCC is to assess on a comprehensive, objective, open and
transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of
human-induced climate change, its potential impacts and options for adaptation and
mitigation.”http://www.ipcc.ch/about/about.htm
IPCCIPCC Intergovernmental Panel on Climate
Change Intergovernmental Panel on Climate
Change“The IPCC does not carry out research nor does it monitor climate related data or other
relevant parameters. It bases its assessment mainly on peer reviewed
and published scientific/technical literature. Its role, organisation,
participation and general procedures are laid down in the ‘Principles Governing IPCC
Work’“
“The IPCC does not carry out research nor does it monitor climate related data or other
relevant parameters. It bases its assessment mainly on peer reviewed
and published scientific/technical literature. Its role, organisation,
participation and general procedures are laid down in the ‘Principles Governing IPCC
Work’“
http://www.ipcc.ch/about/about.htm
IPCCIPCC Working Groups
I: Science knowns, unknowns & projections
II: Impact and Adaption vulnerability: natural and human consequences: + and –
III: Mitigation options for changing human behavior and impact
Task Force on NationalGreenhouse Gas Inventories
Working Groups I: Science
knowns, unknowns & projections
II: Impact and Adaption vulnerability: natural and human consequences: + and –
III: Mitigation options for changing human behavior and impact
Task Force on NationalGreenhouse Gas Inventories
IPCCIPCC 4th Assessment
Released 2007 WGI = 701 pages!
available on lineipcc-wg1.ucar.edu/wg1
available in printCambridge U. Press
4th Assessment Released 2007 WGI = 701 pages!
available on lineipcc-wg1.ucar.edu/wg1
available in printCambridge U. Press
IPCCIPCC 4th Assessment
Released 2007 WGI = 701 pages!
available on lineipcc-wg1.ucar.edu/wg1
available in printCambridge U. Press
4th Assessment Released 2007 WGI = 701 pages!
available on lineipcc-wg1.ucar.edu/wg1
available in printCambridge U. Press
IPCC ARF WGIIPCC ARF WGI Components of Climate Change Components of Climate Change
Accounts for natural processesAccounts for natural processes
eg. Changes in evaporation
eg. Changes in evaporation
eg. Melting permafrost releasing methane
eg. Melting permafrost releasing methane
IPCC Climate DriversIPCC Climate Drivers Greenhouse Gases: CO2, CH4, H2O, NOx Greenhouse Gases: CO2, CH4, H2O, NOx
Grey Bars = Natural Variabilit
y
Grey Bars = Natural Variabilit
y
Com-bined rate of chang
e
Com-bined rate of chang
e
Radiative forcing is a change in the radiation
balance at the top of the atmosphere. Positive increases warming.
IPCC ARF WGIIPCC ARF WGI Radiative Forcing 1750 - 2005 Radiative Forcing 1750 - 2005
Carbon DioxideCarbon Dioxide
“Ozone Layer” absorbs UV, reduces
RF at tropopause
“Ozone Layer” absorbs UV, reduces
RF at tropopauseMethaneMethane
Buildings increase surface albedo
relative to forests
Buildings increase surface albedo
relative to forests
Aerosols (particles) reflect sunlight AND increase cloud cover
(eg. Contrails)
Aerosols (particles) reflect sunlight AND increase cloud cover
(eg. Contrails)
Solar radiation has increased since
1750 (Little Ice Age end)
Solar radiation has increased since
1750 (Little Ice Age end)
IPCC ScenariosIPCC Scenarios A1B
Very rapid economic growth Global population peaks mid-century then declines rapid introduction of new, more efficient
technologies. A2
Very heterogeneous world Continuously increasing global population Regionally oriented economic growth more
fragmented and slower than in other storylines. B2
Same global population as in the A1 rapid changes toward a service and information
economy reductions in material intensity introduction of clean, green technologies.
A1B Very rapid economic growth Global population peaks mid-century then declines rapid introduction of new, more efficient
technologies. A2
Very heterogeneous world Continuously increasing global population Regionally oriented economic growth more
fragmented and slower than in other storylines. B2
Same global population as in the A1 rapid changes toward a service and information
economy reductions in material intensity introduction of clean, green technologies.
IPCC ARFIPCC ARF Continued Warming Continued Warming
What we’re committed to by past
behavior!
What we’re committed to by past
behavior!
Union of Concerned ScientitstsUnion of Concerned Scientitsts Confronting Climate Change in the U.S.
Northeast: Science, Impacts and Solutions
Confronting Climate Change in the U.S. Northeast: Science, Impacts and Solutions
http://www.ucsusa.org/global_warming/
UCC Northeast USUCC Northeast US Climate of New York State Climate of New York State
IPCC ARFIPCC ARF Effects of Changing Mean Effects of Changing Mean
Does not mean it
never gets cold!
Does not mean it
never gets cold!
The SkepticsThe Skeptics Important voices!
Skeptics keep science honest Agreements
CO2 in atmosphere is increasing rapidly
CO2 levels correlate with temperature
Arguments Climate is driven exclusively by insolation
Milankovitch Cycles Sunspot Cycles
Too expensive to reduce CO2: Adapt Global warming is good!
Important voices! Skeptics keep science honest
Agreements CO2 in atmosphere is increasing rapidly
CO2 levels correlate with temperature
Arguments Climate is driven exclusively by insolation
Milankovitch Cycles Sunspot Cycles
Too expensive to reduce CO2: Adapt Global warming is good!
DiscussionDiscussion What should we include & leave out?
How much complexity to include? Should we confront politics directly? How do we handle hostility?
What should we include & leave out? How much complexity to include?
Should we confront politics directly? How do we handle hostility?