claim: Two American researchers allege that U.S. government scientists have  skewed global temperature trends by ignoring readings from thousands of  local weather stations around the world, particularly those in colder  altitudes and more northerly latitudes, such as Canada.
evidence: In a NASA report published in January 2013, Hansen and Sato noted the 5-year mean global temperature has been flat for a decade, which we interpret as a combination of natural variability and a slowdown in the growth rate of the net climate forcing.