Cosmic Rays Introduction Alexis Wagener and Greg Edwards

What are Cosmic Rays? Galactic Cosmic Rays (GCR) are high energy particles that flow into our solar system from outer space Made of pieces of atomic nuclei which have been stripped down in travel Paths are dictated by magnetic fields in the universe Most GCRs stem from the blast remnants of supernovae

The Mechanics An increase in solar activity increases solar wind......ultimately leading to a warming effect...decreasing the cosmic ray flux on earth......decreasing troposphere ionization and cloud water content...

Statistical Juxtaposition Global Temp (Temperature Anomaly in terms of degrees Celsius) vs. Time Cosmic Ray Intensity Decrease (Relative Ion Chamber Count in terms of percentage change) vs. Time Red line shows percentage over Solar Activity Cycles Blue line shows mean percentage

Carbon Dioxide or Solar Forcing? Nir Shaviv argues that a large deal of climate change can be attributed to cosmic ray flux associated with solar activity The trend of increased solar activity in the latter half of the 20th century may be able to account for lower tropospheric cloud formations Beryllium-10 vs. Time (left) Sunspot Number vs. Time (right)

Global Warming Causation Decrease in GCRs lead to reduced ionization of the atmosphere Reduced ionization of the atmosphere leads to reduction in aerosol and cloud formation Svensmark et al. examines relationship between temporary GCR flux decrease and aerosol formation

Solar Cycles and Cosmic Ray Intensity SACs occur over 11 years, resulting in modulation of sunspots SACs are marked by cyclical variation of short-wave solar irradiance, frequency of CMEs and solar flares, and flux of GCRs entering the solar system Ahluwalia examines the relationship between SAC amplitude and decrease in GCRs Observed Sunspots vs. Year

Skepticism on GCR-atmosphere relationship Cloud formation is in the order of hours, while studies show effects to lag in the order of days Svensmark study used small number of GCR decreases relative to other studies Statistical filtering over a Gaussian curve with a small width shifts physical observations to favor the hypothesis