Will the Historic Southeasterly Wind over the Equatorial Pacific in March 2022 Trigger a Third-year La Ni?a Event?     

Xianghui FANG  Fei ZHENG  Kexin LI  Zeng-Zhen HU  Hongli REN  Jie WU  Xingrong CHEN  Weiren LAN  Yuan YUAN  Licheng FENG  Qifa CAI  Jiang ZHU 《大气科学进展》2023,40(1):6-13

Based on the updates of the Climate Prediction Center and International Research Institute for Climate and Society(CPC/IRI) and the China Multi-Model Ensemble(CMME) El Ni?o-Southern Oscillation(ENSO) Outlook issued in April 2022, La Ni?a is favored to continue through the boreal summer and fall, indicating a high possibility of a three-year La Ni?a(2020–23). It would be the first three-year La Ni?a since the 1998–2001 event, which is the only observed three-year La Ni?a event since 1980. By exam...  相似文献   

The Subsurface and Surface Indian Ocean Dipoles and Their Association with ENSO in CMIP6 models     

Ge SONG  Rongcai REN 《大气科学进展》2023,40(6):975-987

This study assesses the reproducibility of 31 historical simulations from 1850 to 2014 in the Coupled Model Intercomparison Project phase 6(CMIP6) for the subsurface(Sub-IOD) and surface Indian Ocean Dipole(IOD) and their association with El Ni?o-Southern Oscillation(ENSO). Most CMIP6 models can reproduce the leading east-west dipole oscillation mode of heat content anomalies in the tropical Indian Ocean(TIO) but largely overestimate the amplitude and the dominant period of the Sub-IOD. Associat...  相似文献   

Interdecadal correlation of solar activity with Tibetan Plateau snow depth and winter atmospheric circulation in East Asia     

ZhiCai Li  Yan Song  Wei Zhang  Jing Zhang  ZiNiu Xiao 《寒旱区科学》2016,8(6):524-535

Studies on the impact of solar activity on climate system are very important in understanding global climate change. Previous studies in this field were mostly focus on temperature, wind and geopotential height. In this paper, interdecadal correlations of solar activity with Winter Snow Depth Index (WSDI) over the Tibetan Plateau, Arctic Oscillation Index (AOI) and the East Asian Winter Monsoon Index (EAWMI) are detected respectively by using Solar Radio Flux (SRF), Total Solar Irradiance (TSI) and Solar Sunspot Number (SSN) data and statistical methods. Arctic Oscillation and East Asian winter monsoon are typical modes of the East Asian atmospheric circulation. Research results show that on interdecadal time scale over 11-year solar cycle, the sun modulated changes of winter snow depth over the Tibetan Plateau and East Asian atmospheric circulation. At the fourth lag year, the correlation coefficient of SRF and snow depth is 0.8013 at 0.05 significance level by Monte-Carlo test method. Our study also shows that winter snow depth over the Tibetan Plateau has significant lead and lag correlations with Arctic Oscillation and the East Asian winter monsoon on long time scale. With more snow in winter, the phase of Arctic Oscillation is positive, and East Asian winter monsoon is weak, while with less snow, the parameters are reversed. An example is the winter of 2012/2013, with decreased Tibetan Plateau snow, phase of Arctic Oscillation was negative, and East Asian winter monsoon was strong.  相似文献   

ENSO对韶关市1951~2013年降雨侵蚀力影响研究     

陈世发 《地理科学》2016,36(10):1573-1580

选取1951~2013年韶关市分月降雨量数据,采用月降雨侵蚀力模型计算降雨侵蚀力,分析ENSO（厄尔尼诺-南方涛动）对韶关市降雨侵蚀力的影响。研究表明：① 韶关市降雨侵蚀力年际变化和年内变化较大,总体呈现波动上升趋势;② 降雨侵蚀力与赤道太平洋SST距平值呈现极显著相关,降雨侵蚀力随SST距平值增加呈现先增加后递减的趋势。ENSO冷暖事件发生时降雨侵蚀力较小,在其它土壤侵蚀因素不变的条件下,此时期的土壤侵蚀相对较轻;③ 降雨侵蚀力与SOI存在显著相关,降雨侵蚀力随着SOI增加而减小;④ 降雨侵蚀力与MEI呈现极显著的正相关关系。  相似文献   

北大西洋ODP1049C孔Aptian-Albian期高频旋回大洋红层的成因:矿物学证据   总被引：2，自引：0，他引：2  

韩志艳  胡修棉  季峻峰  黄永建  黄志诚 《地质学报》2008,82(1):124-132

北大西洋ODP171B航次1049C孔Aptian-Albian期沉积以出现大洋红层与灰色、白色沉积物高频旋回为特征。为了探讨大洋红层的成因,本文进行了矿物学、地球化学、沉积学等方面的研究。漫反射光谱、磁化率和活性铁数据表明,赤铁矿、针铁矿的出现是导致样品由白色向红色转变的矿物学原因。棕色和橙色样品中出现赤铁矿和针铁矿的特征峰,FeR/FeT平均值分别为0.23和0.24,明显区别于其他颜色的样品。磁化率与红层成良好的正相关关系,说明铁氧化物矿物含量的变化是导致磁化率变化的原因。X射线衍射结果表明,不论颜色如何,样品中均含伊利石、高岭石、蒙脱石、绿泥石等粘土矿物,其分布与样品颜色没有直接关系,很可能反映当时物源区气候稳定。ODP1049C孔岩芯沉积物出现橙色、棕色、白色、灰色等颜色的高频变化,颜色过渡接触界线清晰,说明导致红色变化的赤铁矿和针铁矿是沉积期低温氧化的产物。棕色样品中CaCO3含量最低,推测红层所对应的氧化条件是由于较低的有机质堆积速率造成的。  相似文献   

中大西洋营养盐富集实验中浮游植物生长的营养盐限制作用   总被引：1，自引：0，他引：1  

唐松 《矿物岩石地球化学通报》2008,27(2)

借助中国首次环球科学考察航次,在中大西洋航段现场对表层海水进行了添加N、P、Si的营养盐富集实验,通过实验过程中水体营养盐浓度、叶绿素a（Chl-a）浓度以及温度等参数的分析,探讨了实验海区浮游植物生长的营养盐限制作用。结果表明,添加N、P、Si都可造成实验水体中Chl-a浓度明显增大,且N对浮游植物生长的限制作用最明显,其次为P,Si的作用最弱。实验过程中水体N／P值的变化同叶绿素a浓度及浮游植物生长速度（R）没有可对比性,N／P值与后两者之间的相关性都差,可以认为水体中N／P值并不能单独限制浮游植物生长。实验水体温度同Chl-a浓度和R值间也缺乏相关性,表明水体温度同样不能控制浮游植物生长。  相似文献   

2017年汛期气候预测先兆信号的综合分析     

王永光  郑志海 《气象》2018,44(4):565-571

2017年夏季（2017年6—8月）,全国平均降水量348.6 mm,较常年同期（322.6 mm）偏多8.1%,呈现南、北两条多雨带。东亚夏季风偏弱,西太平洋副热带高压显著偏强,脊线位置偏南;欧亚中高纬呈现“两槽一脊”环流型,贝加尔湖地区为正距平控制。赤道中东太平洋海温从前冬冷水向春、夏季暖水发展,20世纪80年代以来容易出现南方多雨的Ⅳ类雨型,夏季贝加尔湖阻塞高压发展。2017年赤道中东太平洋海温从前冬冷水向春、夏季暖水发展,春季北大西洋三极子正位相和2016年欧亚积雪从秋到冬的减少,均有利于夏季贝加尔湖阻塞高压发展,这是夏季主要多雨带位于长江以南的重要前兆信号。  相似文献   

Modulation of the Aleutian–Icelandic Low Seesaw and Its Surface Impacts by the Atlantic Multidecadal Oscillation     

Fei LI  Yvan J.ORSOLINI  Huijun WANG  Yongqi GAO  Shengping HE 《大气科学进展》2018,35(1):95-105

Early studies suggested that the Aleutian–Icelandic low seesaw(AIS) features multidecadal variation. In this study, the multidecadal modulation of the AIS and associated surface climate by the Atlantic Multidecadal Oscillation(AMO) during late winter(February–March) is explored with observational data. It is shown that, in the cold phase of the AMO(AMO|-),a clear AIS is established, while this is not the case in the warm phase of the AMO(AMO|+). The surface climate over Eurasia is significantly influenced by the AMO's modulation of the Aleutian low(AL). For example, the weak AL in AMO|-displays warmer surface temperatures over the entire Far East and along the Russian Arctic coast and into Northern Europe,but only over the Russian Far East in AMO|+. Similarly, precipitation decreases over central Europe with the weak AL in AMO|-, but decreases over northern Europe and increases over southern Europe in AMO|+.The mechanism underlying the influence of AMO|-on the AIS can be described as follows: AMO|-weakens the upward component of the Eliassen–Palm flux along the polar waveguide by reducing atmospheric blocking occurrence over the Euro–Atlantic sector, and hence drives an enhanced stratospheric polar vortex. With the intensified polar night jet, the wave trains originating over the central North Pacific can propagate horizontally through North America and extend into the North Atlantic, favoring an eastward-extended Pacific–North America–Atlantic pattern, and resulting in a significant AIS at the surface during late winter.  相似文献   

An Asymmetric Spatiotemporal Connection between the Euro-Atlantic Blocking within the NAO Life Cycle and European Climates     

Yao YAO  Dehai LUO 《大气科学进展》2018,35(7):796-812

This paper examines an asymmetric spatiotemporal connection and climatic impact between the winter atmospheric blocking activity in the Euro-Atlantic sector and the life cycle of the North Atlantic Oscillation(NAO) during the period 1950–2012. Results show that, for positive NAO(NAO+) events, the instantaneous blocking(IB) frequency exhibits an enhancement along the southwest–northeast(SW–NE) direction from the eastern Atlantic to northeastern Europe(SW–NE pattern, hereafter), which is particularly evident during the NAO+decaying stage. By contrast, for negative NAO(NAO-)events, the IB frequency exhibits a spatially asymmetric southeast–northwest(SE–NW) distribution from central Europe to the North Atlantic and Greenland(SE–NW pattern, hereafter). Moreover, for NAO-(NAO+) events, the most marked decrease(increase) in the surface air temperature(SAT) in winter over northern Europe is in the decaying stage. For NAO+events, the dominant positive temperature and precipitation anomalies exhibit the SW–NE-oriented distribution from western to northeastern Europe, which is parallel to the NAO+-related blocking frequency distribution. For NAO-events, the dominant negative temperature anomaly is in northern and central Europe, whereas the dominant positive precipitation anomaly is distributed over southern Europe along the SW–NE direction. In addition, the downward infrared radiation controlled by the NAO's circulation plays a crucial role in the SAT anomaly distribution. It is further shown that the NAO's phase can act as an asymmetric impact on the European climate through producing this asymmetric spatiotemporal connection with the Euro-Atlantic IB frequency.  相似文献   

ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models     

Renping LIN  Fei ZHENG  Xiao DONG 《大气科学进展》2018,35(5):495-506

Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5(CMIP5), the El Ni o(EN) and La Ni a(LN) events in positive and negative Pacific Decadal Oscillation(PDO) phases are examined. In the observational data, with EN(LN) events the positive(negative) SST anomaly in the equatorial eastern Pacific is much stronger in positive(negative) PDO phases than in negative(positive) phases. Meanwhile,the models cannot reasonably reproduce this difference. Besides, the modulation of ENSO frequency asymmetry by the PDO is explored. Results show that, in the observational data, EN is 300% more(58% less) frequent than LN in positive(negative)PDO phases, which is significant at the 99% confidence level using the Monte Carlo test. Most of the CMIP5 models exhibit results that are consistent with the observational data.  相似文献