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Cosmo-Climatology Cosmic rays, Clouds, and Climate Henrik Svensmark, Center for Sun Climate Research Space- DTU Cosmic Rays and Climate CLOUDS CLIMATE COSMIC RAYS Super Novas Star formation Supported by empirical, observational, and experimental evidence Variations in Cosmic Ray Flux Cause Variations in Earths Climate. What are Cosmic Rays? Heliosphere, Cosmic Rays and Solar Activity Cosmic ray shower (Movie) About 70 muons/s /m2 at the Earths surface In 24 hours about 12 million muons goes through a human body Cosmic rays and climate over the last 10.000 years Bond et al, Science 294, 2001 According to icecores CO2 levels has been constant ~280 ppm Last 1000 years Little Ice Age • Little Ice Age is merely the most recent of a dozen such events during 5 the last 10.000 years Adapted from Kirkby Cosmic rays and climate over the last millennium ”Since everybody thought that the continous crop faliure was caused by witches from devilish hate, the Low Cosmic ray flux whole contry stood up Warmer Climate for their eradication” High Cosmic ray flux Johann Linden Travis ca. 1590Climate Colder Adapted from Kirkby How can STARS influence Climate? Net effect of clouds is to cool the Earth by about 30 W/m2 Link between Low Cloud Cover and Galactic Cosmic Rays? ISCCP IR Low cloud data Calibration? Svensmark & Friis-Christensen, JASTP 1997, Svensmark, PRL 1998, Marsh & Svensmark, PRL, 2000. (update 2005) Cosmic Rays and 1960 -2008 tropospheric temperatures Average temperature between 0-10 km STEP! Using the oceans as a calorimeter to quantify the solar radiative forcing Nir J. Shaviv JGR 2009 Aerosol formation and growth Possible link between clouds and cosmic rays H2SO4 & Water & Organic Vapors CN Cloud Drop (Condensation Nuclei) UCN CCN (Ultra Fine Condensation Nuclei) (Cloud Condensation Nuclei) Size 0.001 mm Nucleation process has been a mystery 0.01 mm 0.1 mm 10 mm Cosmic Ray Ionization & Aerosol formation and growth + H2SO4 & Water CN Cloud Drop (Condensation Nuclei) - Vapors UCN CCN (Ultra Fine Condensation Nuclei) (Cloud Condensation Nuclei) Size 0.001 mm What is the importance of IONS ? 0.01 mm 0.1 mm 10 mm Atmospheric conditions! Gamma source SO2 O3 H2O SKY experiment 2002 - 2006 Gamma source Muon detector Radon detector Steady state experiment q (cm-3 s-1) 0 10 20 30 40 50 60 H2SO4 concentration ~ 2*108 (cm-3) O3 ~ 25 ppb SO2 ~ 300 ppt RH ~ 35% Svensmark et al. Proc. R. Soc. A (2007) 463, 385–396 Coronal Mass Ejections Natural experiments for testing the GCR-atmosphere link AERONET, SSM/I, MODIS and ISCCP data for 5 strongest Forbush decreases Aerosols Clouds Cosmic Rays and Climate ~10% ~100% CLOUDS CLIMATE COSMIC RAYS Super Novas Star formation Supported by empirical, observational, and experimental evidence Variations in Cosmic Ray Flux Cause Variations in Earths Climate. SN variations and Earths Climate Svensmark 2008 Conclusion Particles from space (Cosmic Rays) influence Earths climate, ranging from days to 109 years. •The empirical evidence is large and strong Part of a physical mechanism has been demonstrated experimentally • Involving ions and aerosol formation • Linking to clouds and thereby the energy budget of the Earth Clouds are forcing the Earths climate rather than being a passive component. Understanding the cosmic ray climate link is necessary if we want to understand natural climate changes. The evolution of the Milky Way and the Earth is linked