Relative Solar and Anthropogenic Forcing of

Climate

David Archibald

Melbourne, 24th May 2009

Symposium on Natural Climate Change

Sections

• The Climate Record

• The Solar Driver of Climate

• The Contribution of Carbon Dioxide

The 30 years of High Quality Satellite DataThe Southern Hemisphere is the same temperature it was 30 years ago, the Northern Hemisphere has warmed slightly.

Section 1: The Climate Record

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008

Deg

rees

Cen

tig

rad

e

Southern HemisphereLower Troposphere Temperature AnomalyUAH MSU 1978 - 2009

Global Sea Ice Area is above average.

Arctic sea ice extent is now above normal.

50 Years of Arctic Temperatures – still the same

2009 to date

50 year average

Melting point

70 years of Alaskan Data

30 years of cooling 30 years of warming

Discussion of the issue of sea level in the West Australian 13th May, 2009

Sea level has now been flat for four years.

The oceans started cooling in 2003.

The Correlation between Solar Cycles and Rate of Sea Level Change

That ocean cooling proves the climate models wrong.

A Rural US Data Set

The smoothed average annual temperature of the Hawkinsville (32.3N, 83.5W), Glennville (31.3N, 89.1W), Calhoun Research Station (32.5N, 92.3W), Highlands (35.0N, 82.3W) and Talbotton (32.7N, 84.5W) stations is representative of the US temperature profile away from the urban heat island effect over the last 100 years (Data source: NASA GISS)

14.0

14.5

15.0

15.5

16.0

16.5

17.0

17.5

1893 1903 1913 1923 1933 1943 1953 1963 1973 1983 1993 2003

An

nu

al A

vera

ge

Tem

per

atu

re

A 300 Year Thermometer RecordCentral England Temperature

5.0

6.0

7.0

8.0

9.0

10.0

11.0

1661 1701 1741 1781 1821 1861 1901 1941 1981

Ce

nti

gra

de

Maunder Minimum

Dalton Minimum

The warming out of the Maunder Minimum was three times as fast and four times as large as the warming of the 20th Century.

Medieval Warm Period – Little Ice Age

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

Tem

per

atu

re C

han

ge

Dark Ages

Medieval Warm Period Little Ice Age

ModernWarmPeriod

900 1350 1900

The Earth is due for a Bond event, a rapid cooling every 1,470 years on average.

C14 and ice-rafted debris in North Atlantic seabed cores

Glacial advances over the last two thousand years are coincident with minima in solar activity, on a 210 year (de Vries) cycle. As it is now 213 years since thebeginning of the Dalton Minimum, the Earth is now due for another period of

advancing glaciers.

The Holocene Optimum

Vostok Ice Core Temperature

0

2

4

6

8

10

12

14

-450000 -400000 -350000 -300000 -250000 -200000 -150000 -100000 -50000 0

Tem

pe

ratu

re i

n D

egre

es C

elc

ius

Years Before Present

HoloceneEemian

Vostok InterglacialsSuperimposed andaligned on PeakTemperature

Holocene

Eemian

Holocene

Eemian

3,000 years

The Orbital Drivers of the Ice Ages

Insolation at 60° North

Time is up for our interglacial.

Section 2: The Solar Driver of Climate

0

20

40

60

80

100

120

140

160

180

200

1700 1740 1780 1820 1860 1900 1940 1980 2020

So

lar

Cyc

le A

mp

litu

de

(Wo

lf N

um

ber

)

Dalton

Minimum

Projected

Solar Cycles 1700 - 2030

5 6 24

423

0

20

40

60

80

100

120

140

160

180

2000 2002 2004 2006 2008 2010 2012

Am

pli

tud

e

Schatten

Dikpati

Clilverd

Hathaway

Svalgaard

Badalyan

Lundstedt

Solar Cycle 23

Solar Cycle 24 Predictions as at March 2006

2° C Range in Climate Outcome

May 2009

In 2006, the scientific community was oblivious to the effect of Solar Cycle 24 on climate.

Now that solar activity is flatlining, every sunspeck is examined for its portents.

The Dalton Minimum at Three European Stations 1770 to 1840

6.0

6.5

7.0

7.5

8.0

8.5

9.0

9.5

10.0

10.5

1770 1780 1790 1800 1810 1820 1830 1840

An

nu

al A

ver

ag

e T

emp

era

ture

in C

enti

gra

de

Oberlach

De Bilt

Central England

Dalton Minimum

Solar Cycle Length Relative to Temperature Armagh, Northern Ireland 1796 – 1992

Solar Cycle 22

Solar Cycle 23

Portland, ME

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0

Solar Cycle Length Years

Deg

ree

Cel

ciu

s

Portland, ME

rsq = 0.49

Correlation = 0.70 degrees/annum

Providence, RI

7.0

7.5

8.0

8.5

9.0

9.5

10.0

10.5

9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0

Solar Cycle Length Years

Deg

rees

Cel

ciu

s

Providence, RI

rsq = 0.38

Correlation = 0.62 degrees/annum

Hanover, NH

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0

Solar Cycle Length Years

De

gre

es

Ce

lciu

s

Hanover, NH

rsq = 0.53

Correlation = 0.73 degrees/annum

Solar Cycle 22

Solar Cycle 23

2.2 Degrees C

The baby boomers had the best weather too, caused by a run of short solar cycles.

Figure source: Jan Janssens, annotated by David Archibald

Late 20th Century Solar Cycles compared to Late 19th Century Solar Cycles

Dalton Minimum Repeat?

A repeat of the Dalton Minimum is not precluded by the data to date.July 2009 equates to a 13 year long Solar Cycle 23.

Evolution of Spotless Days in Solar Cycle 23 – 24 Transit

Figure source: Jan Janssens

This is suggesting at least another eight months to the month of solar minimum.

What the Heliospheric Current Sheet is telling us.

0

10

20

30

40

50

60

70

80

1976:05:27 1980:11:19 1985:05:13 1989:11:05 1994:04:29 1998:10:22 2003:04:15 2007:10:08April 2010

Solar Cycle 23Solar Cycle 22Solar Cycle 21

The month of solar minimum may be another year away.

The Solar – Climate Relationship

Lower Magnetic Field Strength

Fewer Sunspots

Less SolarWind

More GalacticCosmic Rays

More Low LevelCloud Formation

More SunlightReflected Into Space

Earth BecomesColder

The Solar Dynamo Index

Interplanetary Magnetic Field

0

2

4

6

8

10

12

14

1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

1970s Cooling Period

Solar Cycle 20 Solar Cycle 21 Solar Cycle 22 Solar Cycle 23

Oulu, Finland Neutron Monitor Count 1960 - 2010

aa Index 1868 - 2008

The aa Index was much weaker during the colder climate of the 19th century.

The Be10 Record

Every cold period shows up in the Be10 record, including the late 19th century one.The modern warm period is evident also. The Be10 record is incontrovertible, and good support for Svensmark’s theory.

The Consequential Climate Shift

1 year increase in solar cycle length

0.7° centigrade decline in temperature

100 kilometre equator-wardshift in growing conditions

Another Dalton Minimum, or Worse?

“The surprising result of these long-range predictions is a rapid decline in solar activity, starting with cycle #24. If this trend continues, we may see the Sun heading towards a “Maunder” type of solar activity minimum - an extensive period of reduced levels of solar activity.”

K.H.Schatten and W.K.Tobiska, 34th Solar Physics Division Meeting, June 2003, American Astronomical Society

A good match with the start of the Maunder Minimum

0

5

10

15

20

25

30

35

1643 1644 1645 1646

Maunder Minimum Current Minimum

Maunder versus current minimum

Section 3: The Warming Effect of Atmospheric Carbon Dioxide

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420

Atmospheric Carbon Dioxide in ppm

Deg

rees

Ce

lciu

s

Pre-industriallevel

Level in 2009Level duringIce Ages

Plant growthshuts down

Relative Contributions of Pre-Industrial and Anthropogenic CO2

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5D

egre

es C

enti

gra

de

20 ppm

280 ppm

380 ppm

600 ppm Existing and PotentialAnthropogenic

Pre-industrial

CO2

Comparison of Climate Sensitivity Estimates 280 ppm to 560 ppm of CO2

Based on Idso Kininmonth Lindzen

Stefan-Boltzmann

Low

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

Inc

rea

se

in

Ea

rth

's T

em

pe

ratu

re i

n D

egre

es

Ce

lciu

s

IPCC

High

Based on Idso Lindzen Spencer

Stefan-Boltzman

Low

How Do the Observational Estimates of FeedbackCompare to Climate Models?

5000

4800

4600

4400

4200

4000

3800

3600

3400

3200

3000

2800

2600

2400

2200

2000

1800

1600

1400

1200

1000

800

600

400

200

0

150 million years ago

400 million years ago

500 million years ago

“the safe upper limit for atmospheric CO2 is no more than 350 ppm” – Dr Hansen of NASA, American Geophysical Union meeting, San Francisco, December 2007

Dr Hansen’s safe upper limit

Pre-industrial level of 280 ppm

Level reached during interglacials, level below which plant growth shuts down

Atmospheric CO2 ppm Correct Safe Limit

Oceans38,000 billion tonnes of carbon

as carbon dioxide

Atmosphere760 billion tonnes of carbon

As carbon dioxide

Vegetation and Soils2,300 billion tonnes

of carbon

119

120100

97

Anthropogenic Carbon

7

Ocean Surface Layer800 billion tonnes of carbon as carbon dioxide in the top 100 metres

Slow exchange

Carbon Dioxide in a Cooling World

Summary

• No sign of the end of Solar Cycle 23 yet – the cooling over Solar Cycle 24 might be as much as 2.8° C.

• The Earth is due for a de Vries cycle (210 year) cooling event and a Bond event (1,470 year cycle).

• Severe cooling over the next 20 years is now a certainty.