Researchers studying global warming have often been confounded by the differences between observed increases in surface-level temperatures and unchanging low-atmosphere temperatures.

A study in the July 2002 issue of Journal of Geophysical Research-Space Physics, published by the American Geophysical Union, proposes for the first time that interstellar cosmic rays could be the missing link between the discordant temperatures observed during the last two decades ...indications of Earth's warming have coincided with decreased cosmic ray intensity during the 20th century.