16 Apr Climate Change

8/10/2019 16 Apr Climate Change

1/73

Earth

s Atmosphere and Climate Change

Big QuestionGlobal Warming Is Happening: What Part Do We Play?


2/73

Global Warming and the Polar Bears of

Hudson Bay


3/73

Is the Global Temperature Rising? Yes, and it isrising globallyHas thetemperature

risen steadily?


4/73

The Last 1,000,000 Years


5/73



6/73


7/73

Variation in the Sun

s Energy May Be A

Reason for Climate Changes The sun

s energy seems to have varied over the agesMidievil Warm period has high solar activity

The Little Ice Age lasted from about 1450 to 1850 andhad relatively low solar activity


8/73Fig. 7-2b, p. 134

The Seasons


9/73



10/73

Changes to Solar Strength

http://en.wikipedia.org/wiki/File:Sunspot_Numbers.png


11/73

Volcanoes Can Alter Climate Volcanic eruptions cool the climate in two ways:- Atmospheric dust reflects sunlight back into space- Smaller dust particles provide water condensingsurfaces, forming clouds

Mt. Pinatubo, Philippines


12/73

Dust from Our Own Activities Also Cools the

Climate

Aerosol pollution particles reduce amount of sunlightreaching EarthEmissions have reduced global warming


13/73

Variations in Ocean Currents May Affect the

Climate

Ocean currents and prevailing winds warm or cool our

planetThe Gulf Stream : a major ocean circulation affectingclimate


14/73

Gulf Stream


15/73

Kuroshio Current www.tec.army.mil
http://images.google.com/imgres?imgurl=http://www.tec.army.mil/publications/elnino/Fig14.gif&imgrefurl=http://www.tec.army.mil/publications/elnino/&usg=__JEOCTdBXBhqSQnCWeaunKfzQJLA=&h=600&w=600&sz=249&hl=en&start=4&um=1&tbnid=KgjK1AaAD73o4M:&tbnh=135&tbnw=135&prev=/images?q=kuroshio+current&um=1&hl=en&rls=com.microsoft:en-us&sa=X


16/73

Oceans can really alter climate?Isthmus of Panama

Emplaced 3.5 3 M years agStarted modern circulation

Gulf stream carries salty Atlantic northCools, sinks

Oceanic conveyor belt

High latitudes cool

JAK 2010 17


17/73

Earth

s energy balance between the amount of

energy coming in from the sun and the amount ofenergy radiated out by the Earth


18/73

Incoming Energy Albedo effect

Energy absorbed by Ocean ~ 90% !!! 19JAK 2010


19/73

The answer lies in the Earth

s energy balance

between the amount of energy coming in from thesun and the amount of energy radiated out by theEarth


20/73Fig. 7-3a, p. 135


21/73


22/73

The Greenhouse Effect, and How It Warms

Earth

s Surface

Earth

s surface temperature determined by four main

factors:1. Amount of sunlight Earth receives2. Amount of sunlight Earth reflects3. Retention of heat by atmosphere4. Evaporation and condensation of water vapor


23/73


24/73

Energy Budget

A h i L l f CO d CH


25/73

Atmospheric Levels of CO 2 and CH 4,Global Temperatures, and Sea

Levels


26/73

Gases produce a greenhouse effect on other planets too


27/73

Review QuestionsIs the Greenhouse Effect a new theory?Is the Greenhouse Effect debated?


28/73

Greenhouse Gases Are Increasing

We are part of the reasonCarbon dioxide has been increasing in the atmospherefor some time


29/73

First suggested early in the 19th century1957: an observatory established on Mauna Loa Volcano,HawaiiScientists now can estimate the carbon dioxide concentrationin ancient atmosphere:- Measure concentration in air bubbles

trapped in polar ice sheetsPeople add to atmospheric carbon dioxide by :

- Burning fossil fuels and wood- Major changes in land use, i.e. cuttingdown forests and removing prairies


30/73

MethaneConcentration more than doubled in the past 200 yearsPeople can add to atmospheric methane by :- Increasing habitats where methane-producingbacteria live

- Increasing number of domesticated ruminants(cows, etc.)

- Processing and burning fossil fuels- Destroying wetlands (releases stored methane)- Increasing the size of landfills and storedorganic matter


31/73

PermafrostFrozen Soil


32/73

Fluorocarbons (CFCs and HFCS)CFCs Once thought harmlessIncreasing in atmosphere about 5% per yearUse as propellants banned in the U.S. in 1978

Montreal Protocol of 1987 was an internationalagreement to reduce and eventually eliminateproduction of CFCsHFCs still used


33/73

Nitrous Oxideincreasing in the atmosphere and likely contributes asmuch as 5% of the anthropogenic greenhouse effect


34/73

OzoneIs a contributing greenhouse gas, but has been difficultto determine percentage of greenhouse effect due toozone


35/73

Warming Potential of the

Main Greenhouse Gases over 100yrs


36/73

Would It Really Be So Serious

If Earth Warmed Up a Bit? Changes in the atmosphere affect living things andhabitatsSteps to forecasting effects:1. Forecast changes in climate and physical

conditions of the oceans and land surfaces

2. Forecast species and ecosystems response


37/73

Computermodels are themajor scientifictool in step oneModel results:global warming will increaseEarth

s surface

temperature by1.5 to 4.5

Cfrom 1990 to2100


38/73

Results of IPCCIntergovernmental Panel on Climate Change (IPCC)90 99% likely that lower atmosphere is warming1906 2005: Ave. temp increased about 0.74 C 1970 2005: Annual greenhouse emissions up 70%Past 50 years: Arctic temp rising almost twice as fast asthe rest of the earthMelting of glaciers and floating sea ice

Prolonged droughts: increasingLast 100 years: sea levels rose 10 20 cm

C i f M d


39/73

Comparison of MeasuredTemperature from 1860 2007 andProjected Changes


40/73

Forecasts suggest that temperatures are rising


41/73

Temperature Data Two Big

ImpactsSoils will dry outGreatest change where the ice is

WHAT ARE THE MAJOR ENVIRONMENTALPROBLEMS WITH THESE IMPACTS FROM THE

PERSPECTIVE OF OUR COURSE?


42/73

The Effects of a Rising Sea LevelRisen naturally since last ice ageIncreases damage from major storms


43/73

-3 -2 -1 0 1 2 3


44/73

Global Warming Affects on World Climate


45/73

AgricultureMay seriously affect world s food supplyThe best agricultural areas may no longer be in North America

Winter snowpacks will store less water for springplanting

Lowering of Water Tables and ReservoirsCould cause serious water supply shortages Water use in some regions is already unsustainable


46/73

Biological and Ecological ChangesBiosphere changes due to damaged ecosystemsSpring arrives up to two weeks earlierEarly spring stresses some speciesSome species are changing their geographic ranges- i.e. Sachem skipper butterflies expanding range


47/73

Species Migration

SpreadsDiseases

Example: Changingrange of diseasecarrying mosquitoes


48/73

West Nile virus is an example of global

warming spreading disease:- Mild winters preserve more mosquitoesin still water locations

- Dry springs increase surface-water sitemosquito and bird concentrations

- Mosquitoes with virus bite uninfectedbirds

- Infected birds are bitten by uninfectedmosquitoes, passing the virus to them

- Hot, wet summers cause mosquito population

to mature and grow rapidly


49/73

Endangered Species What will happen to species that can not migrate noradapt?Case Study: Kirtland

s warbler- an endangered-species success story


50/73

Kirtland

s warblers require a very specific habitatnest only in young jack-pine woodlands

To save these birds, 38,000 acres were set aside inMichigan


51/73

computer simulation shows that jack pine will not beable to grow there in global warming climates

Projected Effects of Global Warming and the


52/73

Projected Effects of Global Warming and theResulting Changes in Global Climate


53/73

Slowing the Temperature RiseReduce production and release of greenhouse gasesFind ways to sequester (store) greenhouse gases Actively cool the climate


54/73

Mitigating Global Warming

Toronto 1988: scientists recommended a 20%reduction in carbon dioxide emissions by 2005Earth Summit 1992: Blueprint for reducing globalemissionsKyoto 1997: Legally binding emission limits We have run out of excuses

Why is the Kyoto Accord so important?


55/73

CO2 Emissions after the Kyoto

Protocol Making energy moreexpensive is a politicalliability everywhere,

says Roger Pielke. When emissionreductions run up againsteconomic growth,economic growth willinevitably win out. There

is no magical solution, soyou better set yourselftangible goals that aren'tdoomed to clash with theiron laws of politics.

35,000


56/73

Fig. 23-7, p. 622

30,000

25,000

20,000

Per capita gross domestic

product (GDP)15,000

1 9 9 6 D o

l l a r s p e r p e r s o n

10,000

5,000Per capita genuine progress indicator (GPI)

0

1950 1960 1970 1980 1990 2000

Year


57/73

Ways to Lower your Emissions Without lowering emissions


58/73

The Fe HypothesisGive me half a tanker of Iron and I

ll give you an Ice Age

- John Martin

To test 1. 7,800 moles of Fe (as FeSO 4) + 15,600 l seawater + conc.HCl to bring it to pH 2 (iron is very insoluble in seawater)2. A 64 km patch over a 24-hour period was made

3. Fe was consumed by the phytoplankton throughout theexperiment4. Patch was followed for 9 days. On the 6th day a low salinityfront moved in from the east, subducting the patch to 20 to 40 m


59/73

Fe concentration in the patch decreased during experiment


60/73

Iron fertilization experiment results


61/73

Iron fertilization experiments to date

Ironex IIronex IISoireeEisenex I

SeedsSeriesSofexEisenex II


62/73

Can we mitigate global warming

with Fe Fertilization


63/73

Problems with the experiments We could only monitor for less than 27 days. What are the long-term impacts

Experiments were relatively small scale

How much Fe will impact atmospheric CarbonDid the carbon get sequestered or is it eaten andrecycled at the surface? Academics are performing the experiments butcompanies want to capitalize


64/73

Experiment SuccessesIronex within two weeks of 1000kg of Fe beingdeposited the equivalent of one hundred redwoodshad been made

Wegener Institute's 2004 Eifexexperiment 300,000 parts carbon fixedto 1 part Fe


65/73

Economic and Social ConcernsHow long a period must carbon be removed forsequestration to have occurred?

Trees decadesBelow thermocline centuriesOcean floor billions of years

Is either time frame long enough to count as carbon

mitigation under the Kyoto protocol?


66/73


67/73


68/73

Exam80 MCQ questions2 hours

Will cover the whole course pretty evenly distributed

A few extra questions on waste and climate as these were not on a mid-term


69/73

IMPORTANT NOTE All exam questions were required to have 5 answerchoices even true false. . .

So you will see things like A) trueB) false

C) MaybeD) MaybeE) Must have options a-e


70/73

What is on the exam?Three types of questions:Facts either you know them or you can usuallyeliminate a couple and make an educated guess

There are very few know the number questions they comefrom the land unit, the ecosystems lecture, waste, populationlecture

Concepts do you understand key materials presented

in lectureFigures two kindsReading and understanding the figuresInterpreting the figures


71/73

What is on the exam?Three types of questions:Facts either you know them or you can usuallyeliminate a couple and make an educated guess

There are very few know the number questions they comefrom the land unit, the ecosystems lecture, waste, populationlecture, chemicals

Concepts do you understand key materials presented

in lectureFigures two kindsReading and understanding the figuresInterpreting the figures


72/73

How to study?


73/73

What else does this plot relateto?

Water pollution Dead Zones, Hong Kong MitigationEcosystems population nichesLand Use Riparian Buffer Zones, Farming practices

Documents

16 Apr Climate Change