ESP 209: Fall ‘07ESP 209: Fall ‘07

Mitigation and Adaptation in a Mitigation and Adaptation in a High CO2 WorldHigh CO2 World

Led by: Lisa Shaffer (lshaffer@ucsd.edu)

Student Coordinators: Danny Richter (drichter@ucsd.edu)Meagan Moore (moore@ucsd.edu)

An Introduction to Climate An Introduction to Climate ChangeChange

ByBy

Danny RichterDanny Richter

Mitigation and AdaptationMitigation and Adaptation

The SystemThe System

Greenhouse Greenhouse GasesGases

IR adsorption (cause of IR adsorption (cause of “the greenhouse effect”) “the greenhouse effect”)

Note that water is the Note that water is the most importantmost important

Note that the Note that the greenhouse gases fill in greenhouse gases fill in gaps gaps

Vibration and rotationVibration and rotation

Greenhouse Greenhouse GasesGases

CO2: CO2: – 100 ppm increase in 150 100 ppm increase in 150

years (~35% increase)years (~35% increase) Methane:Methane:

– ~21x CO2 ~21x CO2

– ~1,000 ppb increase in ~1,000 ppb increase in 150 years (140%)150 years (140%)

N2O:N2O:– (~310x CO2) (~310x CO2)

– ~ 50 ppb increase ~ 50 ppb increase (~19%)(~19%)

Some Historical ContextSome Historical Context

Increasing TemperaturesIncreasing Temperatures

How We KnowHow We Know– SatellitesSatellites– Tree ringsTree rings– Ice coresIce cores

Global Mean Global Mean TemperatureTemperature

– A rise of ~0.7A rise of ~0.7ooC since C since Industrial revolution.Industrial revolution.

Increasing Sea LevelIncreasing Sea Level

Sea level has risen Sea level has risen ~1.5 cm since the start ~1.5 cm since the start of the Industrial of the Industrial revolutionrevolution

Caused by:Caused by:– Thermal expansionThermal expansion– Glacial meltingGlacial melting

How we know: How we know: – Tide gaugesTide gauges

Table 1. Estimated potential maximum sea-level rise from the total melting of present-day glaciers.[Modified from Williams and Hall (1993). See also http://pubs.usgs.gov/factsheet/fs50-98/]table 1

How High Could Sea Level Rise?How High Could Sea Level Rise?

Reduction of the West Antarctic and Greenland ice sheets similar to past reductions would cause sea level to rise 10 or more meters. A sea-level rise of 10 meters would flood about 25 percent of the U.S. population, with the major impact being mostly on the people and infrastructures in the Gulf and East Coast States (fig. 3).

Effect on U.S. Effect on U.S.

Effect WorldwideEffect Worldwide

Nearly one-quarter of Nearly one-quarter of the world's population the world's population lives below 100 feet lives below 100 feet above sea levelabove sea level

100 ft = the size of the 100 ft = the size of the biggest surge during the biggest surge during the 2004 tsunami. 2004 tsunami.

That tsunami killed That tsunami killed 230,000 people.230,000 people.

Effect Worldwide Effect Worldwide

Decreasing IceDecreasing Ice

Annual average Arctic sea ice Annual average Arctic sea ice extent shrunk by 2.7 % per extent shrunk by 2.7 % per decadedecade

Temperatures at the top of Temperatures at the top of permafrost layer have generally permafrost layer have generally increased since the 1980s by up increased since the 1980s by up to 3°Cto 3°C

The maximum area covered by The maximum area covered by seasonally frozen ground has seasonally frozen ground has decreased by about 7% in decreased by about 7% in Northern Hemisphere since Northern Hemisphere since 1900, in spring of up to 15%.1900, in spring of up to 15%.

Decreasing IceDecreasing Ice

See the change

Annual average Arctic sea ice extent shrunk by 2.7 % per decade

Decreasing IceDecreasing Ice

• Ice loss to the sea currently accounts for virtually all of the sea-level rise that is not attributable to ocean warming• About 60% of the ice loss is from glaciers and ice caps rather than from the two ice sheets. •This acceleration of glacier melt may cause 0.1 to 0.25 meter of additional sea-level rise by 2100.•Meier, MF. 2007 Science (317), 1064-1067

Ocean AcidificationOcean Acidification

Basic chemical Basic chemical reaction:reaction:– COCO22 + H + H22O -> O -> HH++ ++

HCOHCO33--

Ocean is a sink for Ocean is a sink for CO2CO2

A sink that is filling A sink that is filling upup

Ocean AcidificationOcean Acidification

A Question of TimescaleA Question of Timescale

The Effects of Climate Change The Effects of Climate Change

Direct EffectsDirect Effects– Atmospheric Atmospheric

CompositionComposition– TemperatureTemperature– Sea LevelSea Level– Ice CoverIce Cover

Indirect EffectsIndirect Effects– Sea LevelSea Level– Biological impactsBiological impacts– Water SupplyWater Supply– Food SupplyFood Supply– City InfrastructureCity Infrastructure– Economic ShocksEconomic Shocks

Economic ShocksEconomic Shocks

The Effects of Climate Change The Effects of Climate Change

Direct EffectsDirect Effects– Atmospheric Atmospheric

CompositionComposition– TemperatureTemperature– Sea LevelSea Level– Ice CoverIce Cover

Indirect EffectsIndirect Effects– Sea LevelSea Level– Biological impactsBiological impacts– Water SupplyWater Supply– Food SupplyFood Supply– City InfrastructureCity Infrastructure– Economic ShocksEconomic Shocks– Our Reaction!Our Reaction!

How To Mitigate Climate Change?How To Mitigate Climate Change?

Sequester Carbon?Sequester Carbon? Build Green?Build Green? Retool Economic Retool Economic

Structures?Structures? Rethink Energy Rethink Energy

Supply?Supply? More Vigorous More Vigorous

Conservation? Conservation? Geoengineering? Geoengineering?

ChallengesChallenges AheadAhead . . . . . .

1.3 billion 1.1 billion

0.3 billion

QuestionsQuestionsand Disucssionand Disucssion

Recent Climate driven by man Recent Climate driven by man and natureand nature

Swindled?

Sea Level Rise Curve for People Sea Level Rise Curve for People AffectedAffected