Tidal phase of water temperature in Qixian well,Shanxi Province is ahead of water level,which is different from the normal tidal relationship between water temperature and water level. Observation curves of this pheno...Tidal phase of water temperature in Qixian well,Shanxi Province is ahead of water level,which is different from the normal tidal relationship between water temperature and water level. Observation curves of this phenomenon are introduced in this paper,and co-seismic response data of water temperature and water level are used to check the thermometer time system,confirming that this phenomenon is true. Using the harmonic analysis method,variations of time difference between water temperature and water level for the M2 wave are worked out,which indicates that this phenomenon exists during the whole observation. According to the variations of phase lags for water temperature and water level,and the survey of observation conditions, it is considered that the abnormal phenomenon may be related to inadequate passage of water caused by a well blockage at the depth where the water temperature probe was set.展开更多
The authors demonstrate that the E1 Nifio events in the pre- and post-1976 periods show two ampli- tude-duration relations. One is that the stronger E1 Nifio events have longer durations, which is robust for the moder...The authors demonstrate that the E1 Nifio events in the pre- and post-1976 periods show two ampli- tude-duration relations. One is that the stronger E1 Nifio events have longer durations, which is robust for the moderate E1 Nifio events; the other is that the stronger E1 Nifio events have shorter durations but for strong E1 Nifio events. By estimating the sign and amplitude of the nonlinear dynamical heating (NDH) anomalies, the au- thors illustrate that the NDH anomalies are negligible for moderate E1 Nifio events but large for strong E1 Nifio events. In particular, the large NDH anomalies for strong E1 Nifio events are positive during the growth and mature phases, which favor warmer E1 Nifio events. During the decay phase, however, the negative NDH anomalies start to arise and become increasingly significant with the evolution of the E1 Nifio events, in which the negative NDH anomalies dampen the sea surface temperature anomalies (SSTA) and cause the E1 Nifio events to reach the SST normal state earlier. This pattern suggests that the nonlinearity tends to increase the intensities of strong E1 Nifio events and shorten their duration, which, together with the previous results showing a positive correlation between the strength of E1 Nifio events and the signifi- cance of the effect of nonlinear advection on the events (especially the suppression of nonlinearity on the SSTA during the decay phase), shows that the strong E1 Nifio events tend to have the amplitude-duration relation of the stronger E1 Nifio events with shorter durations. This result also lends support to the assertion that moderate E1 Nifio events possess the amplitude-duration relation of stronger E1 Nifio events with longer durations.展开更多
基金funded by the 12th "Five-year Plan" of National Science and Technology Sponsored Project,China(2012BAK19B02-04)
文摘Tidal phase of water temperature in Qixian well,Shanxi Province is ahead of water level,which is different from the normal tidal relationship between water temperature and water level. Observation curves of this phenomenon are introduced in this paper,and co-seismic response data of water temperature and water level are used to check the thermometer time system,confirming that this phenomenon is true. Using the harmonic analysis method,variations of time difference between water temperature and water level for the M2 wave are worked out,which indicates that this phenomenon exists during the whole observation. According to the variations of phase lags for water temperature and water level,and the survey of observation conditions, it is considered that the abnormal phenomenon may be related to inadequate passage of water caused by a well blockage at the depth where the water temperature probe was set.
基金jointly sponsored by the National Basic Research Program of China (Nos.2010CB950402 and 2012CB955202)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-QN203)the National Natural Science Foundation of China (No.41176013)
文摘The authors demonstrate that the E1 Nifio events in the pre- and post-1976 periods show two ampli- tude-duration relations. One is that the stronger E1 Nifio events have longer durations, which is robust for the moderate E1 Nifio events; the other is that the stronger E1 Nifio events have shorter durations but for strong E1 Nifio events. By estimating the sign and amplitude of the nonlinear dynamical heating (NDH) anomalies, the au- thors illustrate that the NDH anomalies are negligible for moderate E1 Nifio events but large for strong E1 Nifio events. In particular, the large NDH anomalies for strong E1 Nifio events are positive during the growth and mature phases, which favor warmer E1 Nifio events. During the decay phase, however, the negative NDH anomalies start to arise and become increasingly significant with the evolution of the E1 Nifio events, in which the negative NDH anomalies dampen the sea surface temperature anomalies (SSTA) and cause the E1 Nifio events to reach the SST normal state earlier. This pattern suggests that the nonlinearity tends to increase the intensities of strong E1 Nifio events and shorten their duration, which, together with the previous results showing a positive correlation between the strength of E1 Nifio events and the signifi- cance of the effect of nonlinear advection on the events (especially the suppression of nonlinearity on the SSTA during the decay phase), shows that the strong E1 Nifio events tend to have the amplitude-duration relation of the stronger E1 Nifio events with shorter durations. This result also lends support to the assertion that moderate E1 Nifio events possess the amplitude-duration relation of stronger E1 Nifio events with longer durations.