2010/02/11 by Aviv Solodoch, William R. Boos, Solodoch, Aviv +5
Earth and Planetary Sciences · Environmental Science · #Atmospheric and Oceanic Physics (physics.ao-ph) #Climate variability and models #FOS: Physical sciences #Meteorological Phenomena and Simulations #Oceanographic and Atmospheric Processes
paper · pdf · doi:10.48550/arxiv.1002.2340
openalex publication_date 2010/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The intraseasonal Madden-Julian oscillation (MJO) involves a slow\neastward-propagating signal in the tropical atmosphere which significantly\ninfluences climate yet is not well understood despite significant theoretical\nand observational progress.\n We study the atmosphere's response to nonlinear "Wind Induced Surface Heat\nExchange" (WISHE) forcing in the tropics using a simple shallow water\natmospheric model. The model produces an interestingly rich interannual\nbehavior including a slow, eastward propagating equatorial westerly multiscale\nsignal, not consistent with any free linear waves, and with MJO-like\ncharacteristics. It is shown that the slow signal is due to a Kelvin wave\nforced by WISHE due to the meridional wind induced by a Yanai wave group. The\nforced Kelvin wave has a velocity similar to the group velocity of the Yanai\nwaves, allowing the two to interact nonlinearly via the WISHE term while slowly\npropagating eastward. These results may have implications for observed tropical\nWISHE-related atmospheric intraseasonal phenomena.\n