Global Warming –Beyond CO 2 : The Chilling Stars

1. Global Warming –Beyond CO2:The Chilling Stars Henrik Svensmark, Center for Sun Climate Research Danish National Space Center Basel 2007

2. Global surface temperature

3. How STARS influence Climate

4. Heliosphere, Cosmic Rays and Solar Activity

5. Cosmic ray shower About 70 muons/s /m2 at the Earths surface In 24 hours about 12 million muons goes through a human body

6. Cosmic Rays in a Cloud Chamber

7. Cosmic rays and climate over the last millennium

8. Cosmic rays and climate over the last 10.000 years Bond et al, Science 294, 2001 Last 1000 years Little Ice Age • Little Ice Age is merely the most recent of a dozen such events during the last 10.000 years

9. Indian Ocean monsoon • Solar/GCR forcing of Indian Ocean monsoons on centennial—even decadel—timescales

10. Solar/GCR signal in 20th century warming

11. Summary • Evidence for GCR-climate association on all timescales of Earth’s history • Diversity and quality of evidence appears to exclude mere chance association • Key challenge is to establish the physical mechanism

12. Possible physical mechanism • Mechanism that amplifies tiny GCR energy input

14. Solar variability • No evidence for long-term variations of solar irradiance /UV beyond 11-yr cycle • Recent factor 5 reduction of estimated solar variability since Maunder Minimum (LIA)

15. Coronal Mass Ejections (CME) One month of observation

16. Increase in open solar magnetic flux over the past century Open solar magnetic flux back in time reconstructed from geomagnetic activity Magnetic flux has increased a factor of 2.3 over the last 100 years Since 1963 an increase of 1.4 Lockwood, Stamper, & Wild, Nature, 1999.

17. Global surface temperature

18. Link between Low Cloud Cover and Galactic Cosmic Rays? Svensmark & Friis-Christensen, JASTP 1997, Svensmark, PRL 1998, Marsh & Svensmark, PRL, 2000. (update 2005)

19. Clear association of climate change and 10Be /14C variability (cosmic rays): • Monsoon rainfall seems especially sensitive • But is 10Be /14C variability indicating • a direct effect of cosmic rays on climate? or • a proxy for solar variability (irradiance / UV)?

20. Location of the Solar systems in the Milky Way Relevant for climate?

21. Earth’s climate the last 500 million years Veizer, et al. Nature 2000

22. Cosmic rays and spiral arm crossing 0 Estimated Cosmic Ray Flux 0.5 1 1.5 600 0 200 400 Million of Years Shaviv, PRL (2002)

23. 8 0 4 0.5 0 1 1.5 -4 600 0 200 400 0C Cosmic rays and spiral arm crossing Sea Surface Temperature Anomaly Estimated Cosmic Ray Flux Million of Years Shaviv & Veizer

24. Jordens temperatur gennem 500 millioner år Gennem 500 millioner år har fossiler gemt information, i deres skaller, om hvor varmt det var da de levede

25. What about longer time scales, i.e over the history of the Earth 4.6 Billion years? • Although Cosmic ray fluxes are not known so far back in • time, they can be constructed from knowledge of • Solar Evolution • History of Star Formation Rate in the Milky Way

26. Solar Evolution, Star Rate Formation and Cosmic Rays Outside the Heliosphere SFR CR At Earth CR Svensmark, 2003

27. Interaction between galaxies

28. Cosmic Rays in 4 Billion Years C = 0.92 10 GeV Svensmark, 2006

29. Carbon Isotopes The various reservoirs of carbon on Earth (limestone, biota and CO2 in atmosphere) If more carbon is stored in one of these reservoirs, the isotopic composition of others reservoirs changes to reflect that storage. For instance: if there is more carbon stored in organic matter which is isotopically light, the average carbon composition of dissolved carbon in the ocean and carbon dioxide in the atmosphere will become heavier.

30. Carbon 13 during 3.8 billion years Standard deviation In steps of 400 mill yr Svensmark, Submitted PRL 2005

31. Cosmic Rays in 4 Billion Years C = 0.92 10 GeV Svensmark, Submitted PRL 2005

32. Cold Climate Large temperature difference between equator and pole Strong winds – Mixing of Nutriants Large biological productivity Large fluctuations biological productivity possible Cold Warm Ice Pole Equator

33. Hot Climate Small temperature difference between equator and pole Weak winds – Little Mixing of Nutriants Small biological productivity Small fluctuations in biological productivity Warm Hot Pole Equator

34. Conclusion • Particles from space seems to influence Earths climate, • ranging from years to 109 years. • A part of the missing physical mechanism has been demonstrated experimentally • Involving ions and aerosol formation • Linking to clouds and thereby the energy budget of the Earth • Understanding the cosmic ray climate link could have large • implications in our understanding of climate changes and possible evolution on Earth. • The evolution of the Milky Way and the Earth is linked • It is not suggested that it is the only cause of climate change.

35. IPCC: Model beregninger af Jordens skydække Skydække i %

36. Temperatur udviklingen i atmosfæren:1979 - 2006 Øvre troposfære Middel af troposfære Nedre troposfære Overflade Observationer og modellering fra 49 ”eksperimenter” med 19 klimamodeller Temperature Trends in the Lower Atmosphere:Steps for Understanding and Reconciling Differences, 2006

37. Solar activity (October 2003) EUV (1.5 mill K)

38. Cosmic rays and climate over the last 10.000 years