Madden-Julian oscillation
From Wikinfo
The Madden-Julian oscillation, also called the Madden and Julian oscillation, the 30-60 day or 40-50 day oscillation is a periodic oscillation of variations in wind, sea surface temperature (SST), cloudiness, and rainfall which is believed to affect tropical weather and sometimes mid-latitude weather, see, for example Pineapple Express. It was discovered by Roland Madden and Paul Julian who analysed patterns found in 10 years of upper-level wind observations made at Singapore and atmospheric pressure records at Canton. Their observations were published 1971 in the Journal of Atmospheric Science: "Detection of a 40-50 day oscillation in the zonal wind in the tropical Pacific", J. Atmos. Sci., 28, 702-708.
See also Rossby waves, baroclinic instability, [[El Ni�o]] and Kelvin waves
