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881.
华南夏季降水与全球海温的关系 总被引:14,自引:4,他引:14
徐海明 《南京气象学院学报》1997,20(3):392-399
用1954 ̄1989年华南夏季(6 ̄7月)降水资料和全球月平均海温资料作了简单的相关分析。分析结果表明,华南夏季降水与前期冬季1月的黑潮海温存在显著的负相关,冬季1月黑潮异常增暖有利于华南夏季干旱的产生,而异常偏冷则有利于洪涝的产生。计算结果进一步表明,华南夏季降水与菲律宾、台湾一带的海温以及北大西洋中纬度海温在整个前期春季、同期夏季存在显著的负相关,意叶着以上两海区海温在春夏异常增暖有利于华南夏 相似文献
882.
厄尔尼诺事件对黑龙江省低温洪涝灾害的影响及其预报 总被引:2,自引:0,他引:2
在研究厄尔尼诺(拉尼娜)事件对黑龙江省低温洪涝灾害影响的基础上,提出一种表征厄尔尼诺的指数(ENI)。根据ENI谱分析结果,提出了一种厄尔尼诺事件和拉尼娜事件的统计预测方法。经1997年对强厄尔尼诺和1998年对拉尼娜事件预报检验证明,该方法可行,可在区域和省级短期气候预测中应用。 相似文献
883.
The present paper uses planktonic foraminifera and their stable isotopes to study the changes in the depth of thermocline
(DOT) in the Okinawa Trough since the last 10000 a based on the analysis of Core B-3GC in the northern Okinawa Trough, together
with that of the core in the southern Okinawa Trough. As results show, the thermocline was shallow before 6400 aBP, and deepened
afterward, then became shallow again from 4000 to 2000 aBP. The DOT fluctuations display a positive correlation with those
of sea surface temperature (SST). In addition, the changes in the northern Okinawa Trough are similar to those in the southern
trough, implying a possible connection with the variation of the Kuroshio Current. The changes of SST and DOT suggest that
the Kuroshio Current changed its intensity or main axis from 4000 to 2000 aBP and around about 6400 aBP respectively. Moreover,
the changes of DOT from 8200 to 6400 aBP may indicate a gradual intensification of the Kuroshio Current. 相似文献
884.
NUMERICAL EXPERIMENTS FOR CLIMATE VARIABILITY OF MONSOON UNDER THE UNITED EFFECTS OF ANTARCTIC ICE COVER AND SEA SURFACE TEMPERATURE 总被引:1,自引:0,他引:1
In order to study the mechanisms of climate natural variability under the united effects of antarc-tic ice cover(AIC)and sea surface temperature(SST),we have done a series of numerical experi-ments for the climate variability of the period from January 1981 to December 1983 by using a three-level atmospheric general circulation model(AGCM).Firstly we conduct climate integration for sixyears,then 3 years'control integration from January 16 of the seventh year.Moreover,we do threesensitivity experiments,which are the sensitivity experiments forced by observed SST and AIC.ob-served SST and climatic AIC,observed AIC and climatic SST respectively,to study the climate vari-ability and its mechanisms affected by SST and AIC.We put emphasis on the variability of East Asiamonsoon and the Southern Hemisphere(SH)circulation.In this paper,introduction is made to theresults of control test and the sensitivity experiment forced by observed SST and AIC,and the pre-dictability of the monsoon climate variability is discussed. 相似文献
885.
The influences of the extratropical Pacific SST on the precipitation of the North China region are reexamined with the observational data and studied with numerical simulations by using NCAR CCM2. It is found that there ex-ist high positive correlations between the annual precipitation of the North China region and the extratropical Pacific SST in late spring, especially in two regions, e.g., the Kuroshio Current region and the midlatitude central Pacific re-gion. The numerical simulations with NCAR CCM2 show that the warmer SSTs in the Kuroshio Current region and the midlatitude central Pacific in late spring can generate a large-scale circulation pattern over the Asia-Pacific re-gion that is favorable to the precipitation of the North China region. 相似文献
886.
887.
888.
本文利用热带西太平洋中、美海气第1至第4航次联合考察资料,分析讨论了1986—1987年El Ni(?)o/Southern Oscillation(ENSO)事件期间该区热结构的变化。分析表明,事件期间热带西太平洋暖水域海水热含量显著降低,它与140°W和Nino_1+Nino_2区的SST距平变化恰成反位相关系。此外,温跃层在此期间内上升了50—100m,上混合层明显变浅。这种温跃层的异常上升是与事件期间此区西风异常的出现和赤道两侧正的风应力旋度增大有着密切关系。 相似文献
889.
Various kinds of datasets, such as satellite-derived sea surface temperature (SST), sea surface height, surface velocity produced
by combining surface drifter and satellite altimeter data, and hydrographic data, led to the discovery of an anticyclonic
eddy with lower SST than those of surrounding waters in the Kuroshio recirculation region south of Shikoku, as if the eddy
were cyclonic. This anticyclonic eddy was formed east of Kyushu in late August to early September 1999 from the merger of
two anticyclonic eddies which had migrated in the recirculation region to the sea south of Japan from the east. After the
merger, the anticyclonic eddy strengthened abruptly and began to exhibit the low SST. In October, this eddy coalesced with
the Kuroshio and moved swiftly eastward, accompanied by an amplitude growth of the Kuroshio meander. In mid November, off
the Kii Peninsula, the eddy detached from the meandering Kuroshio. It then moved southwestward and again slowly propagated
westward along the 30°N line. During this period, at least from late October 1999 to January 2000, SSTs over the anticyclonic
eddy were found to be continuously lower than those of surrounding waters. This case tells us that we have to pay careful
attention to the interpretation of mesoscale SST distributions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
890.
Tomohiro Deguchi Yutaka Watanuki Yasuaki Niizuma Akifumi Nakata 《Progress in Oceanography》2004,61(2-4):267
The diets of breeding seabirds can be a good monitor of marine environmental changes. From 1984 to 2001 we monitored the diets of black-tailed gulls (Larus crassirostris) (“surface foragers”), rhinoceros auklets (Cerorhinca monocerata) (“epipelagic divers”), and Japanese cormorants (Phalacrocorax filamentotus) (“bottom divers”) that breed on Teuri Island at the northern boundary of the Tsushima Warm current in the Sea of Japan/East Sea. Between 1984 and 1987, both the gulls and the auklets foraged on the sardine (Sardinops melanostictus), but after 1992, they switched to the anchovy (Engraulis japonica). This change might reflect the collapse of the sardine stock in the late 1980s. In the 1990s, the year-to-year variations of the percentage of anchovy in the diets of the three seabird species showed similar trends: High in 1994 and 1998–2001; and low in 1992–1993 and 1995–1997. The estimated stock size of the anchovy population in the Tsushima Current area was positively correlated with the percentage of mass of anchovy in the seabirds’ diets. Thus, the short-term annual changes of the total anchovy availability, which might reflect SST or the volume transport of Tsushima Current, possibly affected the seabirds diets on this island. 相似文献