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141.
为了分析中国西南秋季旱涝情况,利用西南地区东部1961~2012年的降水资料和区域旱涝指数对该地区秋季旱涝等级进行了评定,并运用NCEP/NCAR再分析资料与英国气象局海温资料对典型旱涝年的成因进行了探讨。结果表明,西南地区东部降水呈显著减少趋势,并在1990年左右发生了突变。旱年秋季,低层在南中国海附近为显著的气旋性环流异常,西南地区上空存在显著的下沉运动,涝年则相反。进一步分析发现,当西太平洋海温偏高时,可以激发罗斯贝波环流异常,对应在南中国海附近存在异常的气旋性环流,临近的西南地区东部处于异常的下沉气流控制,容易发生干旱,涝年则相反。此外,热带西太平洋海温于20世纪80年代中后期发生了由冷转暖的突变,这与随后西南地区东部秋季降水的突变密切相关。 相似文献
142.
利用美国NOAA卫星观测1979-2007年OLR(Outing Longwave Radiation)资料和中国气象局国家气候中心的我国160站月降水资料,分析了热带印度洋-太平洋地区(22.5°S-22.5°N,40°E-80°W)OLR的时空变化特征及和我国夏季降水的关系。结果表明:近29年来热带太平洋南部地区OLR值有增加趋势,而热带印度洋和热带太平洋北部呈减少趋势。EOF分析表明热带印度洋一太平洋地区夏季OLR场具有东西反位相和南北反位相的变化特点,小波分析表明,这种变化主要存在着准5 a和准12 a左右的周期振荡。SVD分析表明,热带印度洋-太平洋夏季OLR场与我国夏季降水密切相关。 相似文献
143.
The pathway of the interdecadal variability in the Pacific Ocean 总被引:15,自引:1,他引:14
Cases of the interdecadal variability in the Pacific Ocean and their evolution were examined in the paper with the statistic
methods (CEOF and composite analysis) over the period of 1950–1993. Observations of oceanic temperatures in the upper 400
m revealed an obvious region of the interdecadal signals in the central North Pacific. Such signals propagated southwestward,
then subducted to the subtropics. The hypothesized link for interdecadal oceanic variability between the subtropics and the
tropics, especially with the western tropical Pacific was unraveled in order to detect the cause of decadal signals in the
tropics. The thermal anomalies subducted in the central North Pacific east to the dateline only reach 18°N. There has been
no further southward propagation since then due to a certain barrier. The origin of the interdecadal signals in the western
tropical Pacific was traced to the southern tropical Pacific. There is a meridional pathway around the dateline where the
signals were loaded. These variabilities were in the nature of the thermocline circulation. 相似文献
144.
Using wavelet transform, the sea surface temperature (SST) during the period of 1982–1999 of the South China Sea and the equatorial Pacific, from datasets of NOAA/AVHRR, was analyzed. It is shown that there are 4- and 8-year interannual oscillations in the eastern equatorial Pacific and 8-year interannual oscillation in the western equatorial Pacific. In terms of attractive time-frequency localization and multi-scale properties of wavelet transform, as shown by the Morlet wavelet, it is found that an in-phase coupling oscillation occurs between the SCS and the equatorial Pacific. The SST changes of SCS will have echoed every event of EI Niño (abnormally warm) and La Niño (abnormally cold) in the equatorial Pacific. There is a positive correlation between the SCS and the western equatorial Pacific in the 8-year time-scale. Evidence is presented that the SST anomalies of the equatorial Pacific influence the SST of the SCS. 相似文献
145.
Benny K. K. Chan Hsi-Nien Chen Paula A. Rodriguez Moreno Laure Corbari 《Journal of Natural History》2016,50(47-48):2961-2984
Due to the extreme scarcity of specimens, little is known about the biodiversity and biogeography of the barnacles of the genus Waikalasma Buckeridge, 1983 (Thoracica: Waikalasmatidae Ross and Newman, 2001), which inhabit the deep sea of the Southwest Pacific. Previous studies reported only a single living species, W. boucheti Buckeridge, 1996, from Vanuatu. In the present study, the collections by French deep-sea expeditions off New Caledonia (NORFOLK 1 & 2, EBISCO, SMIB 2, SMIB 4, SMIB 8, BIOCAL, MUSORSTOM 6, MUSORSTOM 4, MUSORSTOM 5, BATHUS 2), the Solomon Islands (SALOMON 1), Vanuatu (BOA1) and Papua New Guinea (BIOPAPUA) yielded specimens of Waikalasma species from 500 to 800 m depth. From molecular (DNA barcode region cytochrome c oxidase subunit I (COI) and 12S gene) and morphological analysis, a new species Waikalasma dianajonesae sp. nov., and W. boucheti were identified. From molecular phylogenetic analysis, sequence divergence in the DNA barcode region between W. dianajonesae sp nov. and W. boucheti reached > 10%. Waikalasma dianajonesae sp. nov. differs from W. boucheti in the number and size of imbricating plates on the shell and the shape of the tergum. Waikalasma dianajonesae sp. nov. and W. boucheti exhibit sympatric biogeographical distributions in the Southwest Pacific. Waikalasma dianajonesae was found in the waters of Papua New Guinea and Solomon Island, whilst W. boucheti was collected from Papua New Guinea, Vanuatu and New Caledonia waters.
http://zoobank.org/urn:lsid:zoobank.org:pub:713013C7-677A-478F-B5DF-FD4690A7C6A9 相似文献
146.
《Journal of Natural History》2012,46(11):2157-2171
The southern temperate perciform fish family Aplodactylidae is reviewed. The monotypic genus Crinodus is relegated to the synonymy of the genus Aplodactylus, which is recognized as containing five species: A. arctidens Richardson from New Zealand and Australia (Victoria, South Australia and Tasmania); A. lophodon (Günther) restricted to south-eastern Australia (New South Wales and Victoria); A. westralis Russell restricted to south Western Australia; A. etheridgii (Ogilby) from the south-west Pacific (north-eastern New Zealand, Kermadec Islands, Lord Howe Island and Norfolk Island); and A. punctatus Valenciennes from the west coast of South America (Peru and Chile). A key to the species is given. 相似文献
147.
《Journal of Natural History》2012,46(39-40):2573-2590
ABSTRACTBiotic or abiotic factors responsible for temporal or spatial variation in metazoan parasite communities of the green jack Caranx caballus were studied over a nine-year period using samples collected at locations along the south-central Pacific coast of Mexico. A total of 708 fish were collected from six locations between December 2009 and October 2017. Thirty-two parasite species were identified: three Monogenea, nine Digenea, two Cestoda, five Nematoda, eight Copepoda, and three Isopoda. At the component community level, parasite species richness varied significantly from seven (Zihuatanejo 2016) to 18 (Acapulco Bay 2011). The component communities and infracommunities of C. caballus exhibited a similar pattern: low species numbers, low diversity, and dominance by a single species (mainly the monogenean Pseudomazocraes selene or the digenean Bucephalus varicus). Parasite community structure and species composition varied between locations and/or sampling years. The main factors responsible for these variations were host traits such as feeding behaviour and body size, the occurrence of a set of distinctive parasite species, and possible variations in the availability of infected prey between locations. 相似文献
148.
149.
Lag influences of winter circulation conditions in the tropical western Pacific on South Asian summer monsoon 总被引:1,自引:0,他引:1
<正>By means of monthly mean NCEP/NCAR data analyses, this note investigates the lag influences of winter circulation conditions in the tropical western Pacific on South Asian summer monsoon through the methods of composite, correlation and statistical confident test. The results indicate clearly that winter climate variations in the equatorial western Pacific would produce significant influences on the following South Asian summer monsoon, and with the lapse of time the lag influences show clearly moving northward and extending westward features. When winter positive (negative) sea level pressure anomalies occupy the equatorial western Pacific, there is an anticyclonic (cyclonic) circulation anomaly appearing in the northwestern Pacific. With the lapse of time, the anticyclonic (cyclonic) circulation anomaly gradually moves to northeast, and its axis in the west-east directions also stretches, therefore, easterly (westerly) anomalies in the south part of the anticyclonic (cyclonic) circulation anomaly continuously expand westward to the peninsula of India. Undoubtedly, the South Asian summer monsoon is weak (strong). 相似文献
150.
ABSTRACT The systematics of the arboreal sesarmid crab genera Labuanium Serène and Soh, 1970 and Scandarma Schubart, Liu and Cuesta, 2003 is revised. Also included is the poorly known genus Namlacium Serène and Soh, 1970, which is morphologically similar to Labuanium and may also be arboreal in habit. The present study restricts Labuanium to its type species, L. politum (De Man, 1887), and congeners are transferred to Scandarma, Geosesarma De Man, 1892, and three new genera established herein: Circulium gen. nov., Shinobium gen. nov. and Mindanium gen. nov. Two new species of Scandarma are described from Papua New Guinea and Madagascar. Sesarma jacquinoti Ortmann, 1894, previously regarded as a synonym of Scandarma gracilipes (H. Milne Edwards, 1853) (comb. nov.), is here shown to be a junior synonym of Sesarmops angustifrons (A. Milne-Edwards, 1869). Labuanium schuetteii (Hess, 1865) is regarded as conspecific with Scandarma gracilipes (H. Milne Edwards, 1853) (comb. nov.) and the lectotype of the latter species (here designated) is also selected as the neotype of the former, making the two names objective synonyms. Material which had been identified as ‘Labuanium finni Alcock, 1900’ by Pretzmann (1984) from the South Andaman Islands is actually the poorly known Geosesarma thelxinoe (De Man, 1908), which is here referred to a new genus, Andamanium gen. nov. Sesarma finni Alcock, 1900 s.s. is herein assigned to Scandarma. Namlacium crepidatum (Calman, 1925), the only species in the genus, is redescribed and figured and compared with Labuanium and Scandarma. Keys to species of Circulium and Scandarma are provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:414B8DAA-584F-4070-A355-83B583D0D017 相似文献