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151.
王沛霖 《热带气象学报(英文版)》1996,2(1):98-103
Using observational data and the data of disastrous investigation of tornado in Zhujiang River Delta and Guangzhou's sounding from March to May of 1976-1983, the environmental conditions of genesis of tornado are analysed and compared with those of nontornadic local storm.It is found that the favorable conditions of genesis of tornado are lower pressure, unstable stratification and stronger wind in the deep layer of troposphere and higher temperature and humidity in low level, among which, lower pressure, more unstable stratification and layer wind are primary conditions for a severe local storm to possibly develop into a storm with accompanying tornado.The tornado mechanism is not related to vertical wind shear. 相似文献
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Sei-Ichi Saitoh Denzo Inagake Kousei Sasaoka Joji Ishizaka Yukihiro Nakame Toshiro Saino 《Journal of Oceanography》1998,54(5):495-508
Synoptic ship and satellite observations were performed of the Kuroshio warm-core ring (KWCR) 93A and its adjacent waters,
off Sanriku, northwestern North Pacific, between early April and late June 1997. The temporal and spatial distribution of
chlorophylla (Chl-a) and sea surface temperature in the study area were analyzed using data from ADEOS Ocean Color and Temperature Scanner (OCTS)
and NOAA Advanced Very High Resolution Radiometer (AVHRR). The objective of this study was to describe the temporal and spatial
variability of the spring bloom and understand its relationship with the changes in the hydrographic structure of these waters
in and around KWCR 93A. The maximum value of Chl-a concentration in the ring was less than 1 mg/m3 during April. The spring bloom in the ring occurred early in May and the relatively high maximum (>1.0 mg/m3) continued from early in May to mid-June. In late June, a ship-observed surface Chl-a concentration of less than 0.4 mg/m3 suggests that the spring bloom had already declined in and around KWCR 93A. Double spiral structures of warm and cold streamers
appeared from late April to mid-May, which may have an influence on the occurrence of the spring bloom in and around the ring.
In this episodic event, the warm streamer can maintain the available potential energy of the ring and the strength of upwelling
around the ring. The cold streamer provided water with a high Chl-a concentration to the surface layer of the ring. In order to understand the temporal and spatial variability of Chl-a distribution in the ring, the behavior of the warm and cold streamers needs to be taken into consideration. 相似文献
155.
In order to examine the applicability of remotely-sensed ocean color for the estimation of phytoplankton biomass and primary
production in the Oyashio region, the western subarctic Pacific, vertical distributions of chlorophylla concentration and primary production were observed in April and May 1997. Spring bloom was observed in both April and May,
and the surface concentration of chlorophylla exceeded 40 mg m−3. The relationship between the standing stocks of chlorophylla within the layer from the sea surface to one optical depth (0–1/k layer) and the surface chlorophylla concentration is expressed as a Michaelis-Menten equation. The mean ratio of the standing stock of chlorophylla in the euphotic layer to that in the 0–1/k layer was 4.41, this ratio did not significantly differ from 4.61 which was obtained at homogeneous distribution of chlorophylla within the euphotic layer. These facts suggest that the distribution of chlorophylla could be assumed to be homogeneous in the euphotic layer during the spring bloom. Results of primary production measurements
by simulatedin situ method were compared with those by an algorithm with two variables; chlorphylla and non-spectral PAR. Daily primary production in the euphotic layer estimated by the algorithm varied in a range of 38–274%
of that estimated by incubation, although the primary productions by the algorithm agreed with those by the incubation at
a half of stations. Primary production within the euphotic layer calculated using simply the surface data was the same as
that estimated using vertical distribution of chlorophylla. These results show that the primary production in the euphotic layer may be estimated from the remote sensed measurements
during the spring bloom in the Oyashio region. 相似文献
156.
福建温泉的特点及其热源,成因的探讨 总被引:3,自引:0,他引:3
主要介绍了福建温泉的水温,水量,水质,水热异常区大小,空间分布以及产出的地质,地貌的特点,对福建温泉的主要热源观点进行讨论,并对福建温泉的热源,成因和温泉的构造意义提出了初步的想法。 相似文献
157.
根据灌溉用水决策支持系统(DSS)和实时配水的要求,建立了霍泉泉源年出流量随机预测模型和月出流量实时预测模型.经分析表明,随机AR(p)预测模型较适合预测泉源的年出流量,月出流量实时预测模型的预测精度也较高 相似文献
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