\documentstyle{article}

\title{   Comparison between the variations of the length of day (LOD) and Polar motion and the results of Atmospheric excitation \\at different frequency domain}
       \author{L. Dechun, H. Chengli, J. Wenjing\\
    (Shanghai Observatory, Academia Sinica)}
\date{}

\begin{document}
\maketitle

   Using the data series of atmospheric angular momentum (AAM) function
(1982.09 -- 1992.09) provided from the Japan Meteorological Agency
(JMA) the values of the global effective atmospheric excitation in the
length of day and polar motion $(m_1^{'}, m_2^{'}, m_3^{'})$ were computed in this
paper. The comparison between the earth orientation parameters, $m_1,m_2,
m_3$, which were derived by JPL with various data of new techniques and
are called Space 92, and $m_1^{'}, m_2^{'}, m_3^{'}$ were made at different frequency
domain.

  It is shown that the coincidence between $m_1^{'}, m_2^{'}, m_3^{'}$ at Chandler
and seasonal frequency domain is very well. The correlation coeffcients
and energy coincidences are over 0.98 and 0.96 respectively while those
are worse at low frequences of intra-annual and high frequences below
one month.

 It is also shown that the law of causation between AAM excitation and
variation of earth rotation at different domains is not coincident from
correlation delay. May be there are other geophysical processes acting
on the solid earth.

\end{document}
