The rotation of the earth, including the variation of the rotational rate and polar motion, represents the statement of the earth’s overall movement and interactions among the solid earth, atmosphere and ocean on a v...The rotation of the earth, including the variation of the rotational rate and polar motion, represents the statement of the earth’s overall movement and interactions among the solid earth, atmosphere and ocean on a variety of space-time scales. They make the earth’s complex dynamical system under the conservation of angular momentum. The application and development of recent space geodetic techniques greatly promote the researches on the interactions between the earth rotation and the activities of atmosphere and ocean. This review will mainly report the progress in researches on the earth rotation and the activities of atmosphere and ocean as well as the air-sea interaction in the tropics, and prospect the direction for future theoretical investigations.展开更多
Scientists pay great attention to different-time-scale signals in the lengllh of day （LOD） variations △LOD, which provide signatures of the Earth＇s interior structure, couplings among different layers, and potenti...Scientists pay great attention to different-time-scale signals in the lengllh of day （LOD） variations △LOD, which provide signatures of the Earth＇s interior structure, couplings among different layers, and potential excitations of ocean and atmosphere. In this study, based on the ensemble empirical mode decomposition （EEMD）, we analyzed the latest time series of △LOD data spanning from January 1962 to March 2015. We observed the signals with periods and amplitudes of about 0.5 month and 0.19 ms, 1.0 month and 0.19 ms, 0.5 yr and 0.22 ms, 1.0 yr and 0.18 ms, 2.28 yr and 0.03 ms, 5.48 yr and 0.05 ms, respectively, in coincidence with the results of predecessors. In addition, some signals that were previously not definitely observed by predecessors were detected in this study, with periods and amplitudes of 9.13 d and 0.12 ms, 13.69 yr and 0.10 ms, respectively. The mechanisms of the LOD fluctuations of these two signals are still open.展开更多
The term"circadian rhythms"describes endogenous oscillations with ca.24-h period associated with the earth’s daily rotation and light/dark cycle.Such rhythms reflect the existence of an intrinsic circadian ...The term"circadian rhythms"describes endogenous oscillations with ca.24-h period associated with the earth’s daily rotation and light/dark cycle.Such rhythms reflect the existence of an intrinsic circadian clock that temporally orchestrates physiological processes to adapt the internal environment with the external cues.展开更多
The 18th International Symposium on Geodynamics and Earth Tides 2016 covered phenomena that generate temporal variations in geodetic and geophysical observations. In calculating the stress field for Earth tides, the o...The 18th International Symposium on Geodynamics and Earth Tides 2016 covered phenomena that generate temporal variations in geodetic and geophysical observations. In calculating the stress field for Earth tides, the observed geodetic response is used for defining the Earth＇s theology, the Earth internal structure, ＇Earth rotation parameters, and the functioning of the sophisticated instrumentation mounted on Earth and satellites. The instrumentation capable of observing Earth tides, measures changes generated by lithospheric plate movements, as the earthquake cycle and volcanism. Hydrology, tem- perature, and pressure, either of natural or anthropogenic origin, affect the high precision observations, and therefore must be included in this study-realm.展开更多
Like ancient people at other places of the world, the ancient Chinese lived in awe of the Sun. As they felt solar eclipses extremely significant events, they closely observed the occurrence of solar eclipse. Ancient a...Like ancient people at other places of the world, the ancient Chinese lived in awe of the Sun. As they felt solar eclipses extremely significant events, they closely observed the occurrence of solar eclipse. Ancient astronomers further realized very early that solar eclipses were one of the important astronomical phenomena to revise and improve the ancient calendar. Interestingly, ancient emperors regarded solar eclipses as warnings from heaven that might affect the stability of their throne. Consequently, observing and recording solar eclipses became official, which dated far back to ancient China when numerous relevant descriptions were recorded in historical books. These records contribute substantially to China as an ancient civilization, as well as to the research of the long-term variation of the rotation rate of the Earth during >2000 years before the 17th century. This paper briefly reviews the perception, observations and recording of solar eclipses by ancient Chinese astronomers.展开更多
Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts i...Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts in the prevailing surface winds are modulations in rainfall activity. Given the fact that our knowledge of the monsoons is mainly based on the interpretation of the mean values of precipitation, cloudiness and winds;relationships between earth’s rotation or revolution and geographical extent of the global surface monsoons deserve to be highlighted. In the abundant literary and audiovisual production devoted to monsoons worldwide and despite the fact that everyone agrees with physical law which shows that Coriolis force acts to the right in the northern hemisphere (to the left in the southern hemisphere), there is no reference to the relationship between Coriolis force (due to earth’s rotation) effects on troposphere general circulation and geographical extent of the global surface monsoons. Furthermore knowing that the ITCZ oscillations on either side of the equators (due to earth’s revolution) determine the seasons (mainly winter and summer), it is clear that earth’s revolution also plays a crucial role in the seasonal reversal of the prevailing surface winds observed in the regions where monsoons are found. Our main objective is to provide a rational answer to the question: what is a monsoon?展开更多
基金the National KeyProject (Grant No. 970231003), the National Natural Science Foundation of China (Grant Nos. 19833030 and 49634140) and Shanghai Science and Technology Foundation (Grant No. JC14012).
文摘The rotation of the earth, including the variation of the rotational rate and polar motion, represents the statement of the earth’s overall movement and interactions among the solid earth, atmosphere and ocean on a variety of space-time scales. They make the earth’s complex dynamical system under the conservation of angular momentum. The application and development of recent space geodetic techniques greatly promote the researches on the interactions between the earth rotation and the activities of atmosphere and ocean. This review will mainly report the progress in researches on the earth rotation and the activities of atmosphere and ocean as well as the air-sea interaction in the tropics, and prospect the direction for future theoretical investigations.
基金supported by National 973 Project China (2013CB733305)National Natural Science Foundation of China (NSFCs) (41174011,41429401,41210006,41128003,41021061)
文摘Scientists pay great attention to different-time-scale signals in the lengllh of day （LOD） variations △LOD, which provide signatures of the Earth＇s interior structure, couplings among different layers, and potential excitations of ocean and atmosphere. In this study, based on the ensemble empirical mode decomposition （EEMD）, we analyzed the latest time series of △LOD data spanning from January 1962 to March 2015. We observed the signals with periods and amplitudes of about 0.5 month and 0.19 ms, 1.0 month and 0.19 ms, 0.5 yr and 0.22 ms, 1.0 yr and 0.18 ms, 2.28 yr and 0.03 ms, 5.48 yr and 0.05 ms, respectively, in coincidence with the results of predecessors. In addition, some signals that were previously not definitely observed by predecessors were detected in this study, with periods and amplitudes of 9.13 d and 0.12 ms, 13.69 yr and 0.10 ms, respectively. The mechanisms of the LOD fluctuations of these two signals are still open.
文摘The term"circadian rhythms"describes endogenous oscillations with ca.24-h period associated with the earth’s daily rotation and light/dark cycle.Such rhythms reflect the existence of an intrinsic circadian clock that temporally orchestrates physiological processes to adapt the internal environment with the external cues.
基金scientifically supported by the IAG:Commission 3,the IAG Sub-commission 3.1 and International Geodynamics and Earth Tide ServiceThe University of Trieste and the sponsors of the Symposium,namely the OGS(Istituto Nazionale di Oceanografia e di Geofisica Sperimentale)+8 种基金the Dipartimento di Fisica E. Caianiello,University of Salernothe Department of Mathematics and Geosciences of the University of TriesteLeica Geosystems S.P.A.International Association of Geodesy (3 IAG Travel Awards for young scientists)the European Geosciences Union(support to 8 young scientists)the Rector Maurizio Fermeglia of the University of Triestethe President Maria Cristina Pedicchio of OGSInstitute of oceanography and applied geophysicsthrough the contribution of the Italian Space Agency in the frame of the project "MOCASS" (-Mass Observation with Cold Atom Sensors in Space
文摘The 18th International Symposium on Geodynamics and Earth Tides 2016 covered phenomena that generate temporal variations in geodetic and geophysical observations. In calculating the stress field for Earth tides, the observed geodetic response is used for defining the Earth＇s theology, the Earth internal structure, ＇Earth rotation parameters, and the functioning of the sophisticated instrumentation mounted on Earth and satellites. The instrumentation capable of observing Earth tides, measures changes generated by lithospheric plate movements, as the earthquake cycle and volcanism. Hydrology, tem- perature, and pressure, either of natural or anthropogenic origin, affect the high precision observations, and therefore must be included in this study-realm.
文摘Like ancient people at other places of the world, the ancient Chinese lived in awe of the Sun. As they felt solar eclipses extremely significant events, they closely observed the occurrence of solar eclipse. Ancient astronomers further realized very early that solar eclipses were one of the important astronomical phenomena to revise and improve the ancient calendar. Interestingly, ancient emperors regarded solar eclipses as warnings from heaven that might affect the stability of their throne. Consequently, observing and recording solar eclipses became official, which dated far back to ancient China when numerous relevant descriptions were recorded in historical books. These records contribute substantially to China as an ancient civilization, as well as to the research of the long-term variation of the rotation rate of the Earth during >2000 years before the 17th century. This paper briefly reviews the perception, observations and recording of solar eclipses by ancient Chinese astronomers.
文摘Monsoon seasons, occasionally also known as wet seasons or trade-wind littoral seasons, are found in the regions where there is a complete seasonal reversal of the prevailing surface winds. Accompanying these shifts in the prevailing surface winds are modulations in rainfall activity. Given the fact that our knowledge of the monsoons is mainly based on the interpretation of the mean values of precipitation, cloudiness and winds;relationships between earth’s rotation or revolution and geographical extent of the global surface monsoons deserve to be highlighted. In the abundant literary and audiovisual production devoted to monsoons worldwide and despite the fact that everyone agrees with physical law which shows that Coriolis force acts to the right in the northern hemisphere (to the left in the southern hemisphere), there is no reference to the relationship between Coriolis force (due to earth’s rotation) effects on troposphere general circulation and geographical extent of the global surface monsoons. Furthermore knowing that the ITCZ oscillations on either side of the equators (due to earth’s revolution) determine the seasons (mainly winter and summer), it is clear that earth’s revolution also plays a crucial role in the seasonal reversal of the prevailing surface winds observed in the regions where monsoons are found. Our main objective is to provide a rational answer to the question: what is a monsoon?
