To put that link on firmer footing, Benestad used a statistical analysis to determine whether extreme precipitation is related to global mean temperatures. The author used an empirical relationship, showing that daily rainfall amounts follow an exponential distribution, to determine that slow variations in the observed heavy precipitation events (the wet day 95th percentile) on a global scale follow the changes in the global mean temperature. Using this relationship, the author conducted a multiple regression analysis on rain gauge data and global surface air temperature data to show statistically that recent trends in wet day 95th percentile precipitation amounts are influenced by global mean temperatures.
Source: Journal of Geophysical Research-Atmospheres, doi:10.1002/jgrd.50814, 2013 http://onlinelibrary.wiley.com/doi/10.1002/jgrd.50814/abstract
Title: Association between trends in daily rainfall percentiles and the global mean temperature
Authors: R.E. Benestad: The Norwegian Meteorological Institute, Oslo, Norway.
2. The mixed mechanisms of large-earthquake nucleation
An important open question in seismology is: Where do big earthquakes come from? High-energy earthquakes often come from faults under high strain, but the mechanism that underlies their onset is still debated.
The strength of an earthquake depends in part on the size of the region that first starts to slip, with a larger "nucleation" region generally spawning a stronger earthquake. There are two hypotheses for the source of major earthquakes. One is that large earthquakes are necessarily triggered by large nucleation regions. The second is
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American Geophysical Union