排序方式: 共有24条查询结果,搜索用时 31 毫秒
11.
利用GRACE时变重力场模型反演2009-07~2017-06期间亚马孙平原的水储量变化,在移除趋势和季节性周期信号后,计算得到其与ENSO指数之间具有较强的相关关系和一定的时延性,并从季节层面进行分析得到ENSO对亚马孙平原旱、雨两季的不同影响,表现为旱季受到ENSO显著影响而雨季受到的影响则较小。最后,结合水文数据分析指出,ENSO会通过影响降雨量进而影响相应区域的水储量变化,且该现象在流域内两次极端旱灾中有较为突出的表现。 相似文献
12.
Yoo-Jun KIM So-Ra IN Hae-Min KIM Jin-Hwa LEE Kyu Rang KIM Seungbum KIM Byung-Gon KIM 《大气科学进展》2021,38(3):413-429
This study investigates the characteristics of cold clouds and snowfall in both the Yeongdong coastal and mountainous regions under different meteorological conditions based on the integration of numerical modeling and three-hourly rawinsonde observations with snow crystal photographs for a snowfall event that occurred on 29?30 January 2016.We found that rimed particles predominantly observed turned into dendrite particles in the latter period of the episode when the 850 hPa temperature decreased at the coastal site,whereas the snow crystal habits at the mountainous site were largely needle or rimed needle.Rawinsonde soundings showed a well-defined,two-layered cloud structure along with distinctive wind-directional shear,and an inversion in the equivalent potential temperature above the low-level cloud layer.The first experiment with a decrease in lower-layer temperature showed that the low-level cloud thickness was reduced to less than 1.5 km,and the accumulated precipitation was decreased by 87%compared with the control experiment.The difference in precipitation amount between the single-layered experiment and control experiment(two-layered)was not so significant to attribute it to the effect of the seeder?feeder mechanism.The precipitation in the last experiment by weakening winddirectional shear was increased by 1.4 times greater than the control experiment specifically at the coastal site,with graupel particles accounting for the highest proportion(~62%).The current results would improve snowfall forecasts in complicated geographical environments such as Yeongdong in terms of snow crystal habit as well as snowfall amount in both time and space domains. 相似文献
13.
We present the first fine-scale data relating to the occurrence and group characteristics for killer whales (Orcinus orca) in the Hauraki Gulf, New Zealand, as observed from a platform of opportunity (PoP). Group size and composition were examined in relation to water depth and sea surface temperature (SST). From 2000 to 2010, 119 orca encounters were recorded, involving 1 to 18 animals. The encounter rate varied seasonally, being highest in austral spring and lowest in summer. Water depth in which whales were observed was significantly affected by group composition. Sixty-seven percent of groups contained immature animals. Group size was highly skewed towards smaller groups comprising two animals. While this study illustrates that PoPs can be used to indicate the occurrence and group characteristics of highly mobile social species, biases clearly exist. Through identifying such inaccuracies, we present recommendations on how future data should be collected to minimise error and improve datasets for scientific use. 相似文献
14.
济阳坳陷邵家地区沙四段勘探目标多、油气分布不均一且对油气成藏规律认识程度较低,给油气勘探工作带来较大困难。为了能够直观地认识油气成藏差异特征,并可以快速方便地为油气勘探决策部署提供有效指导意见,对研究区沙四段开展成藏差异性定量评价研究。在立足于已有勘探成果的基础上,按照含油气系统区带圈闭分层次对其油气成藏差异性特征进行系统剖析,并充分利用改进的区带与圈闭评价方法以及借助于统计挖掘等数学手段进行定量表征评价。结果表明:总体上研究区沙四段油气成藏差异明显,油源、储层及运聚条件是影响油气成藏差异性的主要因素;北部断阶带成藏条件优越,仍是主要的滚动勘探区,评价出的1类圈闭可作为优选的钻探目标;南部缓坡带成藏条件变化较大,通过加大勘探则有望成为油气资源接替区;西部断裂带成藏条件总体较差,勘探风险较高,局部可作为油气潜力区。开展的成藏差异性定量评价可以有效降低油气勘探成本,深化油气成藏认识,对类似地区的油气效益勘探具有一定借鉴意义。 相似文献
15.
CharacteristicsoffaultrocksandpaleoearthquakesourcealongtheKoktokayErtaifaultzone,Xinjiang,ChinaLANBINSHI1)(史兰斌)CHUANYON... 相似文献
16.
The eighth general meeting of the Geological Society of China was the first meeting in the year 1924, following the Annual Meeting. It was arranged in two evenings as follows. 相似文献
17.
18.
19.
Experimental studies on the evolution process of microcrack patterns in concrete samples con-taining hard inclusions 总被引:1,自引:0,他引:1
ExperimentalstudiesontheevolutionprocesofmicrocrackpaternsinconcretesamplescontaininghardinclusionsZHAOYONGXU1)(许昭永)BINWAN... 相似文献
20.
"A study of migration processes in the Moscow Capital Region over the period 1970-1985 begins by assessing their contribution to overall population growth within the region vis-a-vis natural increase and territorial and administrative changes. Attention then is turned toward movements both within the Moscow Capital Region and between it and other oblasts of the European RSFSR. Although the overall volume of migration within the Moscow capital Region and between it and remaining oblasts of the European RSFSR declined, the relative popularity of the former as a destination among migrants in European Russia remained unchanged." 相似文献