Adaptive L_p estimation and its application to photographic astrometry : Wu Jie, Li Zheng-xin & Wang Jia-ji Shanghai Observatory, Chinese Academy of Sciences, Shanghai 200030

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• 作者：Qian ; Chang-xia ; Gu ; Zhen-nian
• 刊名：Chinese Astronomy and Astrophysics
• 出版年：1996
• 出版时间：October 12, 1996
• 年：1996
• 卷：20
• 期：4
• 页码：507
• 全文大小：80.7 K

文摘

Using the new, highly accurate polar motion data (Space 33 Series) and the atmospheric excitation function compiled by Japan Meteorological Agency we find a relatively strong 40-60 d oscillation, related to atmospheric pressure changes on non-seasonal timescales. The correlation coefficient between χ^g₁ and χ^a₁ is 0.44, that between χ^g₂ and χ^a₂, 0.58, thus the contribution of atmospheric angular momentum to the non-seasonal oscillation in the polar motion is slightly stronger along the Y-axis than the X-axis. The non-seasonal oscillations of the atmospheric and geodetic excitation functions have similar time-varying spectra, especially in the χ₂ component. These facts suggest that the non-seasonal oscillation with periods less than 140 d is at least partially driven by surface air pressure.