Climate Change FI

8/7/2019 Climate Change FI

1/37

Climate Change


2/37

How might the Earths

temperature and climatechange in the future?


3/37

Climate Change in the Past

Changes in the earths climate are neither____ nor ________. For example, 40

millio

n years ago

Antarcticaw

as ice-freeand covered with a beech forest, and theglobal sea level was 230 feet higher than itis today.


4/37


Through the years our climate has been_________ due to: Volcanic emissions

Changes in solar input

Tectonic plate movement

Meteor strikes

Changes in the length of the earths ellipticalorbit

Changes in the tilt of the earths axis as itrotates around the sun


5/37


Through the years our climate has beenchanged due to: The earths axis wobbles

Changes in the suns output of energy relatedto an 11-year cycle of sun spot activity, and a22-year cycle of solar magnetic cycles.


6/37


Global temperature ______ Over the past 900,000 years the troposphere

has experienced prolonged periods of global

cooling and global warming. These alternatingcycles of freezing and thawing are known asglacial and interglacial (between ice ages)periods.

The last ice age ended 13,000 years ago. For the past 1,000 years temperatures have

remained fairly stable, but began rising in thelast century when the forests began to be

cleared and fossil fuels began to be burned.


7/37


We measure past temperatures usingvarious __________ Analysis of ____________ in rocks and

fossils (different radi

oisotopes - parent anddaughter ratio - are formed at different

temperatures)

Plankton and radioisotopes in ocean_________

Tiny _______of ancient atmosphere found inice

Temperature measurements taken at different

depths fro

m ________ drilled in the earthssurface.


8/37


9/37

The Greenhouse Effect


10/37

The Natural Greenhouse Effect

Four major factors shape the earths climate: The ___.

The greenhouse effect warms the earths lower

tro

po

sphere and surface becauseo

f thepresence of___________ ______.

_______ store CO2 and heat, evaporate andreceive water, and move stored heat toother

parts of the world. Natural _______ process through watervapor in

the troposphere (heat rises).


11/37


12/37


Greenhouse gases strongly absorb and emitinfrared energy.

The main greenhouse gases are watervapor,

carbon dioxide, and methane, nitrous oxide Greenhouse gases act like a blanket - they keep

the lower atmosphere warmer, and the upperatmosphere cooler.

The Earths natural greenhouse effect wants tomake the Earths surface unbearably hot(140F), but the cooling effects ofweatherprevent most of that warming from occurring.


13/37


Weathers cooling is accomplished when warmair rises and cold air sinks.

Bottom line: the purpose ofweather is to move

____ from where there is more, towhere there isless. Wind, clouds, rain, every weather patternhas this as its aim.

Sowarm air is moved either higher in the

___________, or higher in ________.


14/37

Heat Transfer

Heat transferred to the air is either sensible (anincrease in air temperature) or latent (watervapor evaporated from the surface).

Latent heat loss by the Earths surface throughevaporation is the dominant mechanism forcooling the Earth.

If neitherwater norvegetation is present, then all

of the suns energy is turned into sensible heat.This is what causes the _____ ____ ______effect.


15/37

Heat Transfer

Warm air is ______ somewhere, and coldair is _______ somewhere else.

This sets up convection _____. This is where the Coriolis Effect is seen.

Remember, in the Northern Hemispherethe air moves to the right. In the SouthernHemisphere the air moves to the left.


16/37

Major Greenhouse Gases

The major greenhouse gases in the loweratmosphere are _____vapor, carbon

_______, _______, and _______oxide. These gases have always been present in the

earths troposphere in varying concentrations.

Fluctuations in the concentrations of these

gases, plus changes in solaroutput are themajor factors causing the changes intropospheric temperature over the past 400,000years.


17/37

Composition of the Earths

Atmosphere

Carbo

n Dio

xide = .03%o

f the Earths Atmo

sphere


18/37

Amount ofManmade CO2


19/37

Major Greenhouse

Gases Increases in average

concentrations of three

greenhouse gases in thetroposphere between 1860and 2004, is mostly due tofossil fuel _________,____________, and___________.


20/37

Sun

Greenhouse

gasesWarming

from

decrease

Cooling

from

increase

CO2 removal

by plants and

soil

organisms CO2 emissions

from land

clearing, fires,

and decay

Heat and

CO2 removal

Heat and

CO2 emissions

Ice and snow cover

Land and soil biota

Long-term

storage

Deep ocean

Shallow ocean

Troposphere

Aerosols


21/37

Glo

bal Warming


22/37

Global Warming and Climate

Change Global warming is _________ than globalclimate change. Warming refers to atemperature increase in the tropospherethat can cause climate change. Climatechange refers to changes in ____ aspectof the climate including temperature,

precipitation, storm intensity, and stormpatterns.


23/37

Global Warming

The major concern in global warming isthat _________ burning of fossil fuels isslowly increasing the carbon dioxidecontent of the atmosphere. We aresupposedly making the blanket slightlydenser. Therefore not as much infrared

energy is being allowed to escape toouterspace. This means more energy is comingin than going out and we are heating up.


24/37

Signs the Troposphere is

Warming In 1988 the UN and the WorldMeteorological Organization establishedthe IPCC (Intergovernmental Panel onClimate Change). It is composed of 2,000climate experts from 70 nations.

In 2001, the IPCC claimed it is very likely

(90-99% confidence level) that thetroposphere is warming.


25/37


Warming The IPCC claims: The earth is the hottest it has been in 400

years

It is hotter than it has been in the last 1,000years

The 10 warmest years since 1861 have

occurred since 1990 Arctic temperatures are rising twice as fast as

those in the rest of the world.


26/37


Warming The IPCC claims: Glaciers and floating sea ice in some parts of

the world are melting and shrinking at an

increasing rate Warmer temperatures in Alaska and Russia

are melting permafrost (which releases moreCO2 and CH4)

The worlds average sea level rose 4-8 inchesduring the last century because of melting iceand the expansion of the ocean water as itstemperature increases.


27/37

Additional Considerations

Oceans have absorbed 50% of the CO2released since the Industrial Revolution,but increasing ocean temperatures, andincreasing ocean acidity cause the oceansto absorb less CO2. So the oceans maynot be able to save us.

QuickTime and adecompressor

are needed to see this picture.


28/37


Cloud cover is still an uncertainty. Lowclouds cool us, high clouds warm us.Some think that airline contrails (whichbecome high clouds) may account for asmuch as halfof the warming we haveexperienced.




29/37


Light-colored outdoor air pollution likeaerosols (microscopic droplets and solidparticles) can slow global warming.

Dark-colored outdoor air pollution like sootcause increased warming.




30/37

Using Mathematical Models

Scientists use ___________ ______(computer models) to predict what thefuture will look like

These models are based on certainassumptions and interactions.

These models are only as good as theassumptions built into them (GIGO)

Coupled General Circulation ModelsCoupled General Circulation Models(CGCMs) couple, or combine, the effects of(CGCMs) couple, or combine, the effects ofthe atmosphere and the oceans on climate.the atmosphere and the oceans on climate.


31/37

Skeptics

- There are scientists who are skeptics anddisagree with the findings of the IPCC.Therefore the idea of a scientific _________is _________.

Some believe we dont know enough about howthe earth works to make assumptions.

Some have a conflict of interest because they work

foroil companies.


32/37

April 1975 - Newsweek


33/37

April 1975 - Newsweek


34/37

Al Gore and A.I.T.

Al Gore won a Noble Peace Prize for hisdocumentary An Inconvenient Truth

He alsowon an Academy Award for An

Inconvenient Truth. But . . .

Gores mansion uses 20 times the energy of the nationalaverage.

Gores zinc mine has received citations for polluting the nearby

creek with its tailings. Gore is heavily invested in companies that stand to profit

tremendously if any carbon offset emission legislation is passed.

Gore has made up to $100,000 for delivering his lecture onenvironmental issues.


35/37

Climategate

Phil Jones, Professor at theUniversity of East AngliasClimatic Research Unit - theorganization that supplies climatedata to the IPCC and the USGovernment.

On 2/15/10 he claimed that helost the data for the hockey stick,there has been no statisticallysignificantwarming since 1995,and that warming periods haveoccurred before, but NOT

because of man-made causes.(1910-1940 and 1975-1998).

He is accused of scientific fraudfor deliberately suppressinginformation and for refusing toshare vital data with critics.




36/37

What We Know ForSure

Mankind ___ producing carbon dioxide as aresult ofour use of a wide variety of fuels, fromcoal and petroleum to natural gas and wood.

The carbon dioxide content of the globalatmosphere has been slowly __________. Weare now 40% ofourway to doubling the pre-industrial concentrations. (Though this is only a

1% increase in the overall natural greenhouseeffect - since carbon dioxide is such a smallpercentage of the atmosphere).


37/37

Climate Change FI

Documents

Transcript of Climate Change FI