[ Objective] The research aimed to study influences of the climate warming on cloudage and cloud-like structure in southern China. [ Method] Annual average temperature, total cloudage and low cloudage in Gan County, N...[ Objective] The research aimed to study influences of the climate warming on cloudage and cloud-like structure in southern China. [ Method] Annual average temperature, total cloudage and low cloudage in Gan County, Nankang, Shangyou and Xinfeng of southern Jiangxi from 2004 to 2011 were selected. Influences of the annual average temperature change on annual average total cloudage, annual average low cloudage and cloud-like structure in southern Jiangxi were analyzed. [ Result] Climate warming was affecting cloudage and cloud-like structure in southern China. When annual average temperature rose, annual average total cloudage and low cloudage both presented decrease trends. When annual av- erage temperature declined, annual average total cloudage and low cloudage both presented rise trends. When annual average temperature was equal to that in prior year at low point, annual average total cloudage and low cloudage increased. Annual average low cloudage was different in mountain area and basin. Influences of the annual average temperature on annual average total cloudage and low cloudage in basin at the low alti- tude presented slow fluctuation form, and had severe influence on that in mountain area at the high altitude. Rise of the annual average temperature had larger influence on high cloudage, while decline of the annual average temperature had larger influence on annual average low cloudage. Under different weather situations, formation and disappearance change of the low cloud had different manifestation forms. [ Conclusion] The research provided scientific basis for studying changes of the cloudage and cloud-like structure in southern China as climate warming.展开更多
During the Mw9 Tohoku-Oki earthquake, gradual increases in both ionosphere total electron content (TEC) and geomagnetic declination signals were observed, starting from ~40 minutes before the mainshock, followed by im...During the Mw9 Tohoku-Oki earthquake, gradual increases in both ionosphere total electron content (TEC) and geomagnetic declination signals were observed, starting from ~40 minutes before the mainshock, followed by impulsive enhancements ~10 minutes after the mainshock. There have been many studies on pre-seismic TEC enhancements, including their characteristics, debates regarding whether TEC anomalies are real signals or artefacts, and the explainable models, and many studies have reported that the impulsive TEC enhancement was caused by a tsunami-induced neutral atmospheric gravity wave. Since TEC and geomagnetic declination anomalies were synchronized so that their origin should be attributed to the same seismic activities, any models must explain both anomalous phenomena, but not the case considered herein. Compared with the corresponding TEC anomalies, we re-examined the characteristics of geomagnetic variation just before and after the mainshock, focusing on the generation process of the impulsive enhancement immediately after the mainshock. We showed that the observed anomaly could be explained if there are quasi-static electric currents of 20 - 30 kA generated near the epicentre area. The possible mechanism of the current generation is discussed in terms of the ionization process in the atmosphere near the sea surface.展开更多
文摘[ Objective] The research aimed to study influences of the climate warming on cloudage and cloud-like structure in southern China. [ Method] Annual average temperature, total cloudage and low cloudage in Gan County, Nankang, Shangyou and Xinfeng of southern Jiangxi from 2004 to 2011 were selected. Influences of the annual average temperature change on annual average total cloudage, annual average low cloudage and cloud-like structure in southern Jiangxi were analyzed. [ Result] Climate warming was affecting cloudage and cloud-like structure in southern China. When annual average temperature rose, annual average total cloudage and low cloudage both presented decrease trends. When annual av- erage temperature declined, annual average total cloudage and low cloudage both presented rise trends. When annual average temperature was equal to that in prior year at low point, annual average total cloudage and low cloudage increased. Annual average low cloudage was different in mountain area and basin. Influences of the annual average temperature on annual average total cloudage and low cloudage in basin at the low alti- tude presented slow fluctuation form, and had severe influence on that in mountain area at the high altitude. Rise of the annual average temperature had larger influence on high cloudage, while decline of the annual average temperature had larger influence on annual average low cloudage. Under different weather situations, formation and disappearance change of the low cloud had different manifestation forms. [ Conclusion] The research provided scientific basis for studying changes of the cloudage and cloud-like structure in southern China as climate warming.
文摘During the Mw9 Tohoku-Oki earthquake, gradual increases in both ionosphere total electron content (TEC) and geomagnetic declination signals were observed, starting from ~40 minutes before the mainshock, followed by impulsive enhancements ~10 minutes after the mainshock. There have been many studies on pre-seismic TEC enhancements, including their characteristics, debates regarding whether TEC anomalies are real signals or artefacts, and the explainable models, and many studies have reported that the impulsive TEC enhancement was caused by a tsunami-induced neutral atmospheric gravity wave. Since TEC and geomagnetic declination anomalies were synchronized so that their origin should be attributed to the same seismic activities, any models must explain both anomalous phenomena, but not the case considered herein. Compared with the corresponding TEC anomalies, we re-examined the characteristics of geomagnetic variation just before and after the mainshock, focusing on the generation process of the impulsive enhancement immediately after the mainshock. We showed that the observed anomaly could be explained if there are quasi-static electric currents of 20 - 30 kA generated near the epicentre area. The possible mechanism of the current generation is discussed in terms of the ionization process in the atmosphere near the sea surface.