Human-induced climate change

Why I am sceptical

Professor of Geology, University of AdelaideEmeritus Professor of Earth Sciences, University of

Melbourne

Professor of Geology, University of AdelaideEmeritus Professor of Earth Sciences, University of

Melbourne

Ian PlimerIan Plimer

Coal Preparation Association, Mackay, 13th September 2101

Coal Preparation Association, Mackay, 13th September 2101

Known CyclesVariable tectonic, PDO143 million year galactic100,000 years orbital41,000 years orbital23,000 years orbital1,500 years solar210 years solar87 years solar22 years solar18.7 years lunar11 years solar

Constant cyclical climate changeConstant cyclical climate change

The next climate change: The future is written in the pastThe next climate change: The future is written in the past

Pleistocene ice age 110,000 to 14,700 years ago

Bölling 14,700 to 13,900 years ago

Older Dryas 13,900 to 13,600 years ago

Allerød 13,600 to 12,900 years ago

Younger Dryas 12,900 to 11,600 years ago

Holocene warming 11,600 to 8,500 years ago

Egyptian cooling 8,500 to 8,000 years ago

Holocene Warming 8,000 to 5,600 years ago

Akkadian cooling 5,600 to 3,500 years ago

Minoan Warming 3,500 to 3,200 years ago

Bronze Age Cooling 3,200 to 2,500 years ago

Roman Warming 500 BC to 535 AD

Dark Ages 535 AD to 900 AD

Medieval Warming 900 AD to 1300 AD

Little Ice Age 1300 AD to 1850 AD

Modern Warming 1850 AD to ….

Climate change over timeClimate change over time

Is the speed and degree of modern climate change unprecedented? Is the speed and degree of modern climate change unprecedented?

400400 300300 200200 100100 00Time – Thousands of Years Before PresentTime – Thousands of Years Before Present

Tem

pera

ture

(°C

)Tem

pera

ture

(°C

) 66

44

22

00

-2-2

-4-4

-6-6

-8-8

-10-10

-12-12

Today

Cooling with increasing CO2Cooling with increasing CO2

TemperatureTemperature

Location, location, location….. Location, location, location…..

Urban heat island effectUrban heat island effect

18801880 19001900 19201920 19401940 2000200019601960 19801980 20202020

23.523.5

22.022.0

20.020.0

18.518.5

An

nu

al M

ean

Tem

pera

ture

(°F

)A

nn

ual M

ean

Tem

pera

ture

(°F

) Tucson U of Arizona (32.2N, 111.0W)Tucson U of Arizona (32.2N, 111.0W)

What is really measured?What is really measured?Tem

pera

ture

Tre

nd

per

Decad

e1940 -

1996 (

°C)

Tem

pera

ture

Tre

nd

per

Decad

e1940 -

1996 (

°C)

0.80.8

0.70.7

0.60.6

0.40.4

0.30.3

0.20.2

0.10.1

00

-0.1-0.110,00010,000 100,000100,000 1,000,0001,000,000 10,000,00010,000,000

Population of CountryPopulation of Country

0.50.5

Reliability of surface measurementsReliability of surface measurements

The Southern Hemisphere is the same temperature it was 28 years ago,

The Northern Hemisphere has warmed slightly

The Southern Hemisphere is the same temperature it was 28 years ago,

The Northern Hemisphere has warmed slightly

The 28 years of high quality satellite data

The 28 years of high quality satellite data

Tem

pera

ture

Vari

ati

on

(°C

)Tem

pera

ture

Vari

ati

on

(°C

)

19801980 19851985 19901990 20002000 2005200519951995

1.01.0

0.50.5

00

-0.5-0.5

1.01.0

0.50.5

00

-0.5-0.5

1.01.0

0.50.5

00

-0.5-0.5

Southern HemisphereSouthern Hemisphere

GlobalGlobal

Northern HemisphereNorthern Hemisphere

Models for atmospheric temperatureModels for atmospheric temperature

-7-7 -6-6 -5-5 -4-4 -3-3 -2-2 -1-1 00 11 22 33 44 55 66 77

Zonally-averaged distributions of predicted temperature change in °K at CO2 doubling (2xCO2-control),

as a function of latitude and pressure level, for four general-circulation models (Lee et al., 2007)

Zonally-averaged distributions of predicted temperature change in °K at CO2 doubling (2xCO2-control),

as a function of latitude and pressure level, for four general-circulation models (Lee et al., 2007)

1010

5050

100100

200200300300

500500700700950950

60°S60°S 30°S30°S EQEQ 30°N30°N 60°N60°N

GFDLGFDL1010

5050

100100

200200300300

500500700700950950

60°S60°S 30°S30°S EQEQ 30°N30°N 60°N60°N

NASA/NSIPPNASA/NSIPP

1010

5050

100100

200200300300

500500700700950950

60°S60°S 30°S30°S EQEQ 30°N30°N 60°N60°N

NASA/GEOS5NASA/GEOS51010

5050

100100

200200300300

500500700700950950

60°S60°S 30°S30°S EQEQ 30°N30°N 60°N60°N

SNUSNU

Radiosonde measurementsRadiosonde measurements

75°N75°N 75°S75°S45°N45°N30°N30°N 15°N15°N EQEQ 45°S45°S30°S30°S15°S15°S

2525

5050

100100

200200

300300

500500700700

10001000

hPahPa

No “greenhouse warming” signature is observed in realityNo “greenhouse warming” signature is observed in reality

2424

2020

1616

1212

88

44

KmKm

Source: HadAT2 radiosonde observations, from CCSP (2006), p116, fig. 5.7ESource: HadAT2 radiosonde observations, from CCSP (2006), p116, fig. 5.7E

We’ll all be roonedWe’ll all be roonedS

ea L

evel (m

m)

Sea L

evel (m

m)

20002000

15001500

10001000

00

500500

18801880 19001900 2000200019201920 19401940 19601960 19801980

Measurement of historic sea levelsMeasurement of historic sea levels

Global average of tide gauges for 20th Century sea level rise is 1-2mm/yr (IPCC, 2001)

Global average of tide gauges for 20th Century sea level rise is 1-2mm/yr (IPCC, 2001)

Port Pirie -0.3mm/yr

Port Adelaide Outer Harbour2.4mm/yr

Fort Denison 1.0mm/yr

Fremantle1.4mm/yr

Southern Oscillation Index

Smoothing of ice core CO2 data- why pre-industrial choice of 280ppm?Smoothing of ice core CO2 data- why pre-industrial choice of 280ppm?

1812-2004 Northern Hemisphere, Chemical Measurement

1812-2004 Northern Hemisphere, Chemical Measurement

CO

2 (

pp

mv)

CO

2 (

pp

mv)

450450

400400

350350

300300

27027018101810 18501850 19001900 1950195019701970

Ice core AntarcticaIce core Antarcticafrom 1958 Mauna Loafrom 1958 Mauna Loa CO2 5 year averageCO2 5 year average

YearYear

Water: Main greenhouse gas & driver of CO2

Water: Main greenhouse gas & driver of CO2

100%100%

80%80%

60%60%

40%40%

20%20%

0%0%WaterVapourWaterVapour

CO2CO2 MethaneMethane N2ON2O MiscGasesMisc

Gases

0.117%0.117% 0.066%0.066% 0.047%0.047% 0.047%0.047%

0.001%0.001% Man madeMan madeNaturalNatural

Doubling CO2 at 385ppmhas no effectDoubling CO2 at 385ppmhas no effect

Atmospheric carbon dioxide in ppmAtmospheric carbon dioxide in ppm

Tem

pera

ture

(°C

)Tem

pera

ture

(°C

)

1.61.6

1.41.4

1.21.2

1.01.0

0.80.8

0.60.6

0.40.4

0.20.2

002020 4040 6060 8080100100120120140140160160180180200200220220240240260260280280300300320320340340360360380380400400420420

The warming effect of atmospheric carbon dioxide

The warming effect of atmospheric carbon dioxide

Submarine volcanicitySubmarine volcanicity

Terrestrial volcanoes change weather (e.g. Tambora 1815)

Submarine supervolcanoes add heat and CO2 to oceans and change climate (64,000km ridges)

10,000 km3/a of cooling water

>95% Earth’s volcanoes

Terrestrial volcanoes change weather (e.g. Tambora 1815)

Submarine supervolcanoes add heat and CO2 to oceans and change climate (64,000km ridges)

10,000 km3/a of cooling water

>95% Earth’s volcanoes

Seafloor SpreadingSeafloor Spreading130°30’W130°30’W 130°00’W130°00’W

45°3

0’N

45°3

0’N

45°0

0’N

45°0

0’N

44°3

0’N

44°3

0’N

Megaplume 2

Megaplume 1

RecentEruptions

RecentEruptions

Greenland ice sheetGreenland ice sheet

3030 -30-3010102020 -20-2000 -10-101515 -15-1555 -5-5Time – Years Before PresentTime – Years Before Present

10001000 400400 200200 100100600600800800

YearYear19401940 19551955196

01960 198519851950195019451945 196

51965

1960

1960

1975

1975

1980

1980

-30°-30°

-40°-40°

-32°-32°

-34°-34°

-36°-36°

-38°-38°

-42°-42°

-29.5-29.5

-32-32

-30-30-

30.5-

30.5-31-31

-31.5-31.5

-32.5-32.5

d180 Site15 GISP2, Boltzman Strobel 1994d180 Site15 GISP2, Boltzman Strobel 199410per. Mov. Avg (d180 Site15 GISP2, Boltzman Strobel 1994)10per. Mov. Avg (d180 Site15 GISP2, Boltzman Strobel 1994)

Greenland ice sheet change in cm/yrGreenland ice sheet change in cm/yr

80°N80°N

75°N75°N

70°N70°N

65°N65°N

60°N60°N

70°W70°W 60°W60°W 40°W40°W

20°W20°W

50°W50°W

80°W80°W

30°W30°W

5.4cm/yrincrease*5.4cm/yrincrease*

*Derived from 11 years of ERS-1/ERS-2 satellite altimeter data, 1992-2003*Derived from 11 years of ERS-1/ERS-2 satellite altimeter data, 1992-2003

30°W30°W 30°E30°E0°0°

150°W150°W

180°180° 150°E150°E

AmundsenSea

AmundsenSea

Antarctic PeninsulaAntarctic Peninsula

90°W90°W

60°E60°E60°W60°W

120°W120°W

2000 Km2000 Km

120°E120°E

Is global warming melting the ice caps and reducing sea ice? NO!Is global warming melting the ice caps and reducing sea ice? NO!

Antarctic Sea Ice TrendsAntarctic Sea Ice Trends

Source: Vaughn, D.G., 2005. Science, 3008, 1877-1878.Source: Vaughn, D.G., 2005. Science, 3008, 1877-1878.

1.01.0

0.50.5

00

-0.5-0.5

-1.0-1.0

-1.5-1.5

YearYear

Source: National Snow and Ice data CentreSource: National Snow and Ice data Centre

19781978 19901990 20002000 20062006

KambIce Stream

KambIce Stream

…. going up!…. going up!

Antarctic Land Ice TrendsAntarctic Land Ice Trends…. going up over most of the continent!…. going up over most of the continent!

Temperature proxy Temperature proxy

H2O(vap) buffer to maximum and minimum temperature

H2O(vap) buffer to maximum and minimum temperature

Thousands of Years AgoThousands of Years Ago

Tem

pera

ture

(°C

)Tem

pera

ture

(°C

)

00

4422

-2-2-4-4-6-6-8-8

40040000 1001005050 300300250250200200150150 350350

1.5

0

0.5

1.0

Du

st

(pp

m)

CO

2 (pp

mv)

CO

2 (pp

mv)

280280

200200

240240260260

220220

Calendar Years Before PresentCalendar Years Before Present

Tem

pera

ture

(°C

)Tem

pera

ture

(°C

)

-30-30

-20-20

-10-10

00

1010

202000 300300 500500 700700 11001100200200100100 400400 900900600600 10001000800800

Temperature proxyTemperature proxyCosmogenic isotopes (C14; also Be10, Al26, Cl36, Ca41,

Ti44, I129)Cosmogenic isotopes (C14; also Be10, Al26, Cl36, Ca41,

Ti44, I129)

10,000BC10,000BC 4,000BC4,000BC 1AD1AD6,000BC6,000BC8,000BC8,000BC 2,000BC2,000BC 2000AD2000AD

100100

8080

6060

4040

2020

00

ModernMaximum

ModernMaximum

MaunderMinimumMaunderMinimum

SpörerMinimum

SpörerMinimum

OortMinimum

OortMinimum

WolfMinimum

WolfMinimum

MedievalMaximumMedievalMaximum

DaltonMinimum

DaltonMinimum

It’s easy to stop climate change - All we have to do is:It’s easy to stop climate change - All we have to do is:

STOP bacteria doing what bacteria do

STOP ocean currents changing

STOP plate tectonics and continent movement

STOP orbital changes to Earth

STOP variations in energy released from Sun

STOP orbit of Solar System in Galaxy

STOP supernoval eruptions

STOP bacteria doing what bacteria do

STOP ocean currents changing

STOP plate tectonics and continent movement

STOP orbital changes to Earth

STOP variations in energy released from Sun

STOP orbit of Solar System in Galaxy

STOP supernoval eruptionsWhen we’ve stopped these natural

processes,

if human-induced then:

PERSUADE China and India to stay poor

When we’ve stopped these natural processes,

if human-induced then:

PERSUADE China and India to stay poor

A few little problemsA few little problems

Warmings in industrial age (1860-1880, 1910-1940, 1975-1998; CO2 rise only correlates with 1975-1998 warming)

Industrial age coolings when CO2 increasing (1880-1910, 1940-1975, 1998-present)

Peak of Little Ice Age coolings (Dalton, Maunder, Spörer, Wolf) when few sunspots; 20th Century solar maximum and no sunspots

Pre-industrial Minoan, Roman and Medieval Warmings (with no sea level changes); SL rise of 130m 12,000-6,000 years ago, SL fall of 2m over last 6,000 years

Greater past variability and changes

Six of six great ice ages when atmospheric CO2 up to 1000 times higher than now

Arctic warming (fanfare); Antarctic, oceanic (PDO) and atmospheric cooling (silence)

Warmings in industrial age (1860-1880, 1910-1940, 1975-1998; CO2 rise only correlates with 1975-1998 warming)

Industrial age coolings when CO2 increasing (1880-1910, 1940-1975, 1998-present)

Peak of Little Ice Age coolings (Dalton, Maunder, Spörer, Wolf) when few sunspots; 20th Century solar maximum and no sunspots

Pre-industrial Minoan, Roman and Medieval Warmings (with no sea level changes); SL rise of 130m 12,000-6,000 years ago, SL fall of 2m over last 6,000 years

Greater past variability and changes

Six of six great ice ages when atmospheric CO2 up to 1000 times higher than now

Arctic warming (fanfare); Antarctic, oceanic (PDO) and atmospheric cooling (silence)