Climate Change

Oversimplified but irrefutable:1) Global temperatures are rising.2) Many atmospheric pollutant levels are rising.3) The pollutants that are rising help to trap

heat.

• NPR Article: Drought

Is Climate Changing?• Records since

1880 show: hottest 10 years have happened since the new millenium (2000)

• Journals: Lakes/rivers freeze about 1 week later and thaw about 1 week earlier than 150 years ago

• Night temps increase more than day temps (gg’s prevent escape of heat at night but don’t affect incoming radiation during day)

Is Climate Changing ?(cont)

• Declining arctic wildlife• Climate extremes – Still have very cold days,

but the number of very hot days is increasing

• Coral reef bleaching• Global glacial retreat – Ex: Montana. Glacier

National Park had 130+ glaciers. None left by 2030.

• Thinning of arctic ice:

Evidence of Past Climatea.k.a.: “Proxy” Measurements

• Journals “Dear Diary…”• Glacier lengths• Ice cores

• Pollen deposits in lake sediment

• Coral reefs

Natural Climate Change Events:

Random Events• Volcanic Eruptions• Asteroid Impacts• Cosmic Radiation• Tectonic Plate Fluctuations

Regular Events• 11- year sunspot cycles• 22- year solar magnetic cycles• 18.6 year lunar cycle– affects tides, atmosphere

• Earth’s tilt/Orbital fluctuations

5 Primary Skeptic Arguments• “Cloud Effect” – Higher temperatures more evaporation

more clouds. Clouds reflect sunlight. It’ll cool us down.• “Glacial melt is normal” – Glaciers began retreating 150 years

ago, before we began messing things up. • “It’s Natural!” – This is natural, and we are insignificant. The

changes are natural fluctuations. Human activities are too insignificant on a global scale.

• “Computer models are flawed” – Models indicate our CO2 levels should be higher based on our f.f. use. If we can’t even predict CO2 concentrations correctly, we can’t predict what is happening with climate change.

• “An Ice-Age is Coming” – We’re going to need the heat. The past 8,000 years have been warm and stable. We’re overdue. We’ll be grateful for the extra CO2 warming.

Greenhouse Effect

• We need some gg’s to keep the planet warm. Without them, Earth would be uninhabitably cold.

• However: All things in moderation. We have too much.

Be Neighborly: Get to know your 5 GG’s

Contribution toward climate change depends on 3 factors:

1. Abundance/quantity2. Atmospheric Lifetime – The

amount of time required to restore equilibrium after an increase in the atmospheric concentration. • The amount of time until a

gg leaves the system.• Over time, molecules are lost

or deposited in soil, water, vegetation, biological systems, etc.

3. “Global Warming Potential” GWP • Shows how much

heat can be stored per molecule (ability to absorb radiation)• Measures each gas

against the GWP of CO2 (which is given the standard of “1 GWP”)

5 Primary Greenhouse Gases• CO2 (Carbon Dioxide)– Sources: Fossil fuel burning

• CH4 (Methane)– Sources: landfills (greatest), coal mines, rice

paddies, cow farts• Hydro-, Per-, Chloro- Fluorocarbons (H, P, C-

FCs) and Sulfur Hexafluoride (SF6)

– The only gg with NO Natural Contribution.

– Sources: ski wax, fishing line, formerly coolants and aerosols

• O3 (Ozone)– Sources: smog

• N2O (Nitrous Oxide)– Sources: burning organics, f.f. burning,

fertilizers

5 Primary Greenhouse Gases• CO2

– Overall contribution: 50%

• CH4

– Overall Contribution: 18%

• H, P, CFC, SF6

– Overall Contribution: 15%

• O3

– Overall Contribution: 12%

• N2O– Overall Contribution: 6%

Ozone Extremely Brief Atmospheric Lifetime:

hours-days

GWP – Not Calculated due to brevity of atmospheric lifetime

History of CO2• 1st record: 1957, Mauna Loa Hawaii

monitoring stationDiscoveries:• 1. Natural seasonal CO2

fluctuation. Seasonal plants take up CO2 in summer (CO2 low), dormant in winter (CO2 high).

• 2. Steady CO2 increase every year since then (confirmed world-wide)

• 3. Natural CO2 change: 0.0002 ppm/yr

• 4. Anthropogenic CO2 change: 2-3 ppm/yr

http://www.esrl.noaa.gov/gmd/webdata/ccgg/trends/co2_data_mlo.pdf

BLACK Carbon (soot)What’s the problem? Low albedo soot particles float in air

(lowering albedo of air) and land on stuff (lowering albedo of exposed surface materials).

• Sources: diesel engines, open cook stoves, wood burning, forest fires

• Source locations: developing countries (esp. India, China)• Atmospheric Lifetime: ~ 1 month• Control technologies: retrofit engines to capture black

carbon, use nat gas instead of diesel, replace open cook stoves with solar cookers or more efficient cook stoves

• Potential benefits: Prompt (!) reduction of climate change, improved air quality, lung/health improvement

Manipulation of Data

Analyze the following graph. Look for:• Evidence of wordplay/exaggeration of evidence• Biased interpretation of data• Manipulative use of graph tools

• “Plants need CO2”

Why care? Effects of Climate Change • Biodiversity and ecosystem loss (ex: coral reefs) • Species extinction (ex: “Islands in the sky” loss of

high altitude climates)• Loss of terrestrial glaciers = loss of drinking water

(glacial melt provides water)• Incr. disease. (Mosquito population is major vector

for disease)• Ocean acidification (CO2 + H2O = H2CO3….carbonic

acid)

Why care? Effects of Climate Change • Precipitation/weather pattern changes

war/conflict over water, resources and viable land• Sea level rise due to: 1) melting terrestrial glaciers

and 2) thermal expansion of oceans• Millions will migrate, esp. India & China• Developing nations will be the hardest hit and least

financially able to adapt• Largest changes will be seen in the arctic:– Albedo change from glacier tundra initiates a positive

feedback loop– Thermohaline circulation disruption– CO2 and CH4 released from melting permafrost

Psychology of the Climate Change Issue

• In a group of 3-4, develop a list of reasons why some people don’t believe in climate change.

• http://www.npr.org/templates/story/story.php?storyId=121105095

• http://www.npr.org/templates/story/story.php?storyId=5530483

Debate Activity:• Your group will be given one of the five primary skeptic

arguments to refute.• Your role: Educated environmentalist.• My role: “Devil’s advocate”. I play the skeptic who doesn’t

believe in climate change. • Use textbook, notes, and internet research to reject my

argument. You can use notes/graphs/etc. during our debate.

• I pick one member of your group to represent you. The score earned by that person is what is received by every member of the group.

• http://www.npr.org/templates/story/story.php?storyId=124008307&sc=emaf

Thermohaline Circulation/Ocean Conveyor• Term for the interaction

between the ocean and the atmosphere.

• It moderates earth’s climates.

• Currents transport warm water from the equator poles and cold water from the poles equator.

• The process is driven by 2 marine variables:1.Temperature (cold poles, warm equator)2.Salinity (saltier poles, “waterier” equator)

Thermohaline Circulation cont.Prior to climate change:• Tropics: Surface water is

warmed by the sun and diluted by rainwater and runoff

• Poles: Cold and dense surface water sinks anddraws up warm water (from the equator) to replace it

If the system stops Its moderating effect will cease…Equator will be hotterPoles will be colder (potential to trigger

ice age)

Future potential conditions:• Tropics: Getting saltier due to

increased temps which increase evaporation

• Poles: Getting waterier due to glacial melt and precipitation increases at high latitudes

• …the salinity gradient which drives circulation is diminishing

Mechanisms for g.g. Control:Cap and Trade

Principle: A government sets a limit (cap) on the amount of a pollutant that can be emitted by an industry.

Effect: Companies that emit more pollution must buy credits from those who pollute less– The buyer pays a charge to pollute (--> financial

incentive to install emissions reduction equipment)– The seller is rewarded for having reduced

emissions

Cap and Trade cont.

Cap and Trade (cont)Acid Rain Cap and Trade Program • Program details:– Addressed SO2 and NOx

emissions– Began in 1990 with

the Clean Air Act• Results:– Reduced emissions faster

and cheaper than anticipated– By the year 2002:• SOx emissions were 9% lower than in 2000

• NOx emissions were 13% lower than in 2000

Kyoto Protocol• Set a Cap and Trade system

for developed nations to reduce g.g. emissions

• Nations could sell emissions between countries

• Poorer, developing nations (ex: India) exempt. Reasoning: – Wealthy countries made

the g.g. mess, they take the lead in cleaning it up

– Would place undue financial burden on economy of a developing nation (“taxing a child”)

• July, 2001, 178 nations agreed to regulate CO2, CH4 and N2O

• Not us! • Reasoning:1. India and China didn’t, so we won’t.2. Bush: “we’re going to put the interests of our own country first and foremost”3. Due to our lifestyle, wouldhave required a 40%reduction in energy consumption

Kyoto Failure produced no binding agreementMeanwhile…

Kyoto Goal: 5% lower g.g. emissions than 1990 levelsGlobal emissions are 54% higher than in 19902011 Top 3 g.g emitters:1. China (10b tons)2. U.S. (5.9b tons)3. India (2.5 b tons)

• China emissions increased 10%• U.S. emissions declined 2%• India emissions increased 7%

Copehagen Summit

FAIL• The countries approved a

5-page document that recognizes the need to limit global temperatures from rising no more than 2o Celsius over 10 years, but doesn't require countries to take measures to address climate change.

• Ended in everyone pointing fingers at everyone else

• Widely considered to be a failure.

El Nino Southern Oscillation (ENSO)Affects a sloshy bathtub of warm water between

Indonesia and South AmericaMost Years:• More water is in the

west Pacific due to westerly winds

Results in:• 1. Torrential rain (ex:

monsoons) in Australia and SE Asia

• 2. Dry wind and deserts from Chile to S. California

El Nino Years:• Change in pressure, ocean

temperature and wind direction to an easterly direction…produces unusually warm waters in equatorial Pacific

• Happens every 3-5 years, lasts a few months to 1 year or more

• Dramatically increased rainfall in southern U.S. and Peru

• Drought in west Pacific, Australia

How does El Nino relate to climate change?

• Studies of 130,000 year old coral indicate ENSO events are becoming:– More irregular– Stronger– Warm ocean temperatures are spreading• Warm water spawns hurricanes, typhoons, coral reef

bleaching, marine life death• La Nina– Characterized by unusally cold waters in the equatorial

Pacific

The Future

• IPCC – Intergovernmental Panel on Climate Change– The panel of international

scientists who evaluate the risks of anthropogenic climate change

• Projected temperature increases:– 1.1 - 4.4o C by 2100 (the last

ice age was 5oC colder)• Scenarios • B.A.U. – Business as Usual

(red)

http://www.breathingearth.net

• http://www.breathingearth.net

Scenarios: Why don’t we know?Each scenario attempts to project variables such as:• Population…declining, stable or growing? By how

much?• Continued reliance on f.f.’s? (coal is cheap!)

Incorporation of renewable energy? By how much?• Heterogenous (haves vs have-nots)world? More

equitable, resource-homogenized world? How much?

• Non-linear feedback loops (increasing at an increasing rate), positive feedback loops…

Greatest changes to be seen in the Arctic• Permafrost soil is made of swampy,

boggy, high CO2 and CH4 soils• It’s no longer “perma”…it’s thawing. • Melting of terrestrial glaciers and ice

reveal dark underlying tundra…much lower albedo -->creates positive feedback loop

• Thawing of permafrost soils could release more CO2 than all of the fossil fuels ever burned, another positive feedback loop.

• Aquatic glaciers also have a higher albedo than ocean…melting creates more positive feedback

How to Cool the Planet• Aerosols (ex: PM liquids/solids, sulfates,

dust, sea salt, black carbon, volcanic ash) – High albedo aerosol particles (esp sulfates)

“whiten” clouds – Low albedo aerosol particles (esp black

carbon) “darken” atmosphere – Aerosols can turn ordinarily large, “dark”

droplets in clouds into many smaller, whiter droplets which reflect light better

– Sometimes produce more cloud precip, sometimes produce less. (Poorly understood at this time)

How to cool the planet (continued)

• Volcanic eruptions• Increase g.g. emissions cost• Government regulation• Subsidies– Make renewable energy less expensive than coal energy

• Efficiency/mileage standards• Cap and trade

Cool the Planet (cont.)• Efficiency incentives– Energy Guide, Energy Star

• De-couple climate science from politics!

• Buy green power • Building design (deciduous

trees on S. side of structures)

• Research and Development• Education

VS

Cool Planet (cont.): Carbon Capture and Sequestration (CCS)

• Carbon Sequestration – the process of capturing atmospheric C in fixed sites.– Ex: geological

sequestration, agricultural sequestration

– Concerns re: leakage, effect of CO2 on geology

– Technology is ~8 yrs away

Stabilization Wedge(use a portfolio of mitigation strategies)

Stabilization Wedge Options (pick 7)• Vehicle efficiency• Improve mass transit• More efficient buildings (windows, walls,

doors)• Reduce deforestation, replant• Conservation tillage (slow soil erosion, draw

CO2 into soil)• Build wind farms• Build solar panels (various options)• Improve coal efficiency• Replace coal plants with natural gas• Carbon Sequestration• Nuclear power• Biomass fuels (from waste biomass)• Hydrogen fuel cell cars

CLOUD EFFECT

• Cloud Effect– Clouds insulate (make it warmer!) as well as reflect

(make it cooler!) – prepare the pencils!

What the Ozone Hole and Climate Change

have in common:

• Nothing.

Related Issue: Climategate/Swifthack• November, 2009, Climatic Research Unit, Norwich, England• 1,000 emails, 3,000 other documents illegally stolen• Criticism focused on ~6 emails• Summary findings by objective analysts (AP and peer-

reviewers) determined:1. Scientists had made an effort to withhold unsupportive

scientific details from climate skeptics, but those details were minor in relation to all compiled and cross-referenced data – “claims by climate skeptics that the emails demonstrated scientific

misconduct amounting to fabrication of global warming were unfounded, and emails were being misrepresented to support these claims.”

– No scientific organizations have reversed their position that climate change is anthropogenic and an immediate concern.

Climategate/Swifthack (cont)2. A few emails referred to deletion of emails and withholding

of data- Review of files determined that no information was deleted

3. Scientists had used the word “trick” in an easily misrepresented context:– "I've just completed Mike's Nature trick of adding in the real temps

to each series for the last 20 years (ie, from 1981 onwards) and from 1961 for Keith's to hide the decline.“

– The “trick” was combining proxy records with actual temperature records. Proxy readings are substituted with actual readings for available years. The “decline” refers to a phenomenon called “divergence”. Tree ring data (proxy) conflicts with actual temp data in far N. Hemisph trees.

– Trees in the rest of the world do not exhibit “divergence”– Ice cores and lake sediments do not exhibit “divergence”