Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitation of slow MJO-like Kelvin waves in the equatorial atmosphere by
  Yanai wave-group via WISHE-induced convection   The intraseasonal Madden-Julian oscillation (MJO) involves a slow
eastward-propagating signal in the tropical atmosphere which significantly
influences climate yet is not well understood despite significant theoretical
and observational progress.
  We study the atmosphere's response to nonlinear "Wind Induced Surface Heat
Exchange" (WISHE) forcing in the tropics using a simple shallow water
atmospheric model. The model produces an interestingly rich interannual
behavior including a slow, eastward propagating equatorial westerly multiscale
signal, not consistent with any free linear waves, and with MJO-like
characteristics. It is shown that the slow signal is due to a Kelvin wave
forced by WISHE due to the meridional wind induced by a Yanai wave group. The
forced Kelvin wave has a velocity similar to the group velocity of the Yanai
waves, allowing the two to interact nonlinearly via the WISHE term while slowly
propagating eastward. These results may have implications for observed tropical
WISHE-related atmospheric intraseasonal phenomena.

7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org