In this paper,many observations show that the thermal states including the SST,the convective activities in the west- ern Pacific warm pool largely influence the interannual and intraseasonal variations of summer circ...In this paper,many observations show that the thermal states including the SST,the convective activities in the west- ern Pacific warm pool largely influence the interannual and intraseasonal variations of summer circulation and the cli- mate anomalies in East Asia.Moreover,it is pointed out that there is a teleconnection pattern of summer circulation anomalies in the Northern Hemisphere,the so-called East Asia/Pacific pattern. The cause of the teleconnection pattern is studied by using the theory of quasi-stationary planetary wave propaga- tion,and it may be due to the propagation of quasi-stationary planetary waves forced by heat source around the Philippines.Moreover,this pattern is well simulated by using a quasi-geostrophic,linear,spherical model and the IAP-GCM,respectively.展开更多
利用美国冰雪资料中心(The National Snowand Ice Data Center)提供的近40年逐周的卫星反演雪盖资料,考察了冬季欧亚大陆北部新增雪盖面积(Total Fresh Snow Extent,冬季TFSE)与我国夏季(6~8月)气候异常的关系。分析发现,冬季TFSE与我...利用美国冰雪资料中心(The National Snowand Ice Data Center)提供的近40年逐周的卫星反演雪盖资料,考察了冬季欧亚大陆北部新增雪盖面积(Total Fresh Snow Extent,冬季TFSE)与我国夏季(6~8月)气候异常的关系。分析发现,冬季TFSE与我国夏季气候异常存在明显关联:当冬季TFSE偏大时,夏季贝加尔湖以东易盛行异常冷低压,内蒙古东部和东北西部易出现凉夏,同时,东亚副热带西风急流增强,西太平洋副热带高压易加强且西伸和北扩,江南地区在副高的控制下易干热;冬季TFSE偏小时的情况相反。这种显著关联独立于ENSO事件,并且在近40年来较为稳定;冬季TFSE与我国江南夏季降水在20世纪90年代初均发生过一次十年际尺度变化,表现为在20世纪90年代初之后,冬季TFSE(江南降水)明显减小(增多),同时,冬季TFSE与江淮夏季降水的正相关关系明显增强。进一步的分析表明,冬季TFSE可能通过某种途径来影响东亚副热带急流的变化,进而影响我国夏季气候异常。展开更多
This investigation aims to study the El-Niño-Southern Oscillation (ENSO) events in these three phases: El Niño, La Niña, and neutral. Warm and cold events relate to the Spring/Summer seasons. This paper...This investigation aims to study the El-Niño-Southern Oscillation (ENSO) events in these three phases: El Niño, La Niña, and neutral. Warm and cold events relate to the Spring/Summer seasons. This paper will search for connections between the ENSO events and climate anomalies worldwide. There is some speculation that those events would be necessary for the climate anomalies observed worldwide. After analyzing the data from the reports to the ENSO, it shows almost periodicity from 1950-2023. We emphasized the occurrence of El Niño two years, when it was most prominent, and the climate anomalies (following NOAA maps), 2015 and 2023. The results indicated that the observed climate anomalies couldn’t be linked to the abnormal events observed. The worldwide temperatures in those years enhanced mostly in 2023. It shows an abnormal behavior compared with all the years scrutinized and analyzed since the records began. Therefore, there must be unknown factors beyond ENSO that rule the worldwide temperatures and the climate anomalies observed.展开更多
In this study, a group of indices were defined regarding intensity (P), area (S) and central position (λc, Фc) of the Aleutian low (AL) in the Northern Hemisphere in winter, using seasonal and monthly mean h...In this study, a group of indices were defined regarding intensity (P), area (S) and central position (λc, Фc) of the Aleutian low (AL) in the Northern Hemisphere in winter, using seasonal and monthly mean height field at 1000-hPa. These indices were calculated over 60 winter seasons from 1948/1949 to 2007/2008 using reanalysis data. Climatic and anomalous characteristics of the AL were analyzed based on these indices and relationships between the AL, and general circulations were explored using correlations between indicesP, λc, and Pacific SST, as well as Northern Hemisphere temperature and precipitation. The main results are these: (1) AL is the strongest in January, when the center shifts to the south and west of its climatological position, and it is the weakest in December when the center shifts to the north and east. (2) AL intensity (P) is negatively correlated with its longitude (λc): a deeper low occurs toward the east and a shallower low occurs toward the west. On a decadal scale, the AL has been persistently strong and has shifted eastward since the 1970s, but reversal signs have been observed in recent years. (3) The AL is stronger and is located toward the east during strong E1 Nifio winters and vice versa during strong La Nifia years; this tendency is particularly evident after 1975. The AL is also strongly correlated with SST in the North Pacific. It intensifies and moves eastward with negative SST anomalies, and it weakens and moves westward with positive SST anomalies. (4) Maps of significance correlation between AL intensity and Northern Hemisphere temperature and rainfall resemble the PNA teleconnection pattern in mid-latitudes in the North Pacific and across North America. The AL and the Mongolian High are two permanent atmospheric pressure systems adjacent to each other during boreal winter over the middle and high latitudes in the Northern Hemisphere, but their relationships with the E1 Nifio/La Nifia events and with temperature and precipitat展开更多
2021/2022年冬季,赤道中东太平洋海温偏低,导致贵州省气温偏低、降水偏多,但凝冻日数总体偏少,呈前期偏弱后期偏强的阶段性分布特征。利用贵州省84个国家气象观测站逐日观测资料、NCEP/NCAR(National Centers for Environmental Predict...2021/2022年冬季,赤道中东太平洋海温偏低,导致贵州省气温偏低、降水偏多,但凝冻日数总体偏少,呈前期偏弱后期偏强的阶段性分布特征。利用贵州省84个国家气象观测站逐日观测资料、NCEP/NCAR(National Centers for Environmental Prediction/National Center for Atmospheric Research)再分析资料以及NOAA(National Oceanic and Atmospheric Administration)海温资料等,分别从海温场、高度场、风场、温度场和水汽条件等方面对凝冻阶段性特征成因进行分析。结果表明:高层南支锋区总体呈前期偏弱后期偏强,为贵州省凝冻阶段性特征提供了有利的大尺度环流背景。2022年1月26日之后,对流层低层切变线稳定维持、偏北气流异常强盛使0℃等温线南压明显。同时随着偏南气流持续增强,对流层低层水汽辐合也迅速增强,并维持低层辐合中层辐散的不稳定层结和上升运动,为贵州省凝冻阶段性特征提供了有利的水汽条件。温度场上,前期暖层较为深厚,冷空气势力前期偏弱后期偏强,为贵州省凝冻阶段性特征提供了有利的温度条件。但由于整个冬季无逆温层存在,导致3次区域性凝冻过程强度均偏弱。展开更多
The impact of solar activity on climate system is spatiotemporally selective and usually more significant on the regional scale. Using statistical methods and solar radio flux(SRF) data, this paper investigates the im...The impact of solar activity on climate system is spatiotemporally selective and usually more significant on the regional scale. Using statistical methods and solar radio flux(SRF) data, this paper investigates the impact of the solar11-yr cycle on regional climate of Northeast Asia in recent decades. Significant differences in winter temperature,precipitation, and the atmospheric circulation over Northeast Asia are found between peak and valley solar activity years. In peak years, temperature is higher over vast areas of the Eurasian continent in middle and high latitudes, and prone to producing anomalous high pressure there. Northeast Asia is located to the south of the anomalous high pressure, where the easterlies prevail and transport moisture from the western Pacific Ocean to the inland of East Asia and intensify precipitation there. In valley years, temperature is lower over the Eurasian continent and northern Pacific Ocean in middle and high latitudes, and there maintain anomalous low pressure systems in the two regions. Over the Northeast Asian continent, north winds prevail, which transport cold and dry air mass from the high latitude to Northeast Asia and reduce precipitation there. The correlation coefficient of winter precipitation in Northeast China and SRF reaches 0.4, and is statistically significant at the 99% confidence level based on the Student's t-test. The latent heat flux anomalies over the Pacific Ocean caused by solar cycle could explain the spatial pattern of abnormal winter precipitation of China, suggesting that the solar activity may change the climate of Northeast Asia through air–sea interaction.展开更多
利用1979~2013年NCEP/NCAR月平均再分析资料及NOAA研究中心的CMAP(CPC Merged Analysis of Precipitation)月平均降水资料,通过定义欧亚—北太平洋间大气质量迁移指数IMAMEP,分析了春季欧亚—北太平洋上空大气质量迁移(MAMEP,Migrati...利用1979~2013年NCEP/NCAR月平均再分析资料及NOAA研究中心的CMAP(CPC Merged Analysis of Precipitation)月平均降水资料,通过定义欧亚—北太平洋间大气质量迁移指数IMAMEP,分析了春季欧亚—北太平洋上空大气质量迁移(MAMEP,Migration of Atmospheric Mass over Regions between Eurasia and North Pacific)的年际变化规律及其与同期中国气候异常的联系。结果表明:在北半球中高纬度存在一个纬向分布的欧亚—北太平洋遥相关型,且其可能对中国同期气候异常的形成具有重要影响。春季MAMEP指数具有显著的长期趋势,同时还具有2~4年及5~7年的振荡周期及明显的年代际变化特征。垂直环流和波动运动对欧亚—北太平洋间大气质量迁移具有重要作用。大气质量在欧亚西部低层异常辐合,高层异常辐散,在中、西太平洋地区低层异常辐散,高层异常辐合,在纬向上构成了顺时针的垂直环流圈,将西北太平洋地区的大气质量变动与欧亚大陆上空的变动联系了起来。另外,来自西欧大陆的波扰能量可传播至北太平洋,有利于这些区域上空位势高度异常扰动的维持。IMAMEP与春季同期降水及地表气温异常关系密切。IMAMEP为正时,东亚以北地区、鄂霍次克海西岸以及西欧沿岸降水显著减少,欧亚西部及我国华北地区降水显著增加。850 h Pa上西伯利亚受反气旋式环流控制,太平洋上空受气旋式环流控制,引起欧亚大陆北部地表显著增温,西伯利亚以东、我国东北、华北—江淮地区及韩国、日本南部地表显著降温。西欧—我国西北部分地区大面积显著降温现象与这两个地区受异常反气旋东侧的偏北气流影响有关。这些结果有利于人们更深刻认识区域春季气候异常形成机理。展开更多
文摘In this paper,many observations show that the thermal states including the SST,the convective activities in the west- ern Pacific warm pool largely influence the interannual and intraseasonal variations of summer circulation and the cli- mate anomalies in East Asia.Moreover,it is pointed out that there is a teleconnection pattern of summer circulation anomalies in the Northern Hemisphere,the so-called East Asia/Pacific pattern. The cause of the teleconnection pattern is studied by using the theory of quasi-stationary planetary wave propaga- tion,and it may be due to the propagation of quasi-stationary planetary waves forced by heat source around the Philippines.Moreover,this pattern is well simulated by using a quasi-geostrophic,linear,spherical model and the IAP-GCM,respectively.
文摘利用美国冰雪资料中心(The National Snowand Ice Data Center)提供的近40年逐周的卫星反演雪盖资料,考察了冬季欧亚大陆北部新增雪盖面积(Total Fresh Snow Extent,冬季TFSE)与我国夏季(6~8月)气候异常的关系。分析发现,冬季TFSE与我国夏季气候异常存在明显关联:当冬季TFSE偏大时,夏季贝加尔湖以东易盛行异常冷低压,内蒙古东部和东北西部易出现凉夏,同时,东亚副热带西风急流增强,西太平洋副热带高压易加强且西伸和北扩,江南地区在副高的控制下易干热;冬季TFSE偏小时的情况相反。这种显著关联独立于ENSO事件,并且在近40年来较为稳定;冬季TFSE与我国江南夏季降水在20世纪90年代初均发生过一次十年际尺度变化,表现为在20世纪90年代初之后,冬季TFSE(江南降水)明显减小(增多),同时,冬季TFSE与江淮夏季降水的正相关关系明显增强。进一步的分析表明,冬季TFSE可能通过某种途径来影响东亚副热带急流的变化,进而影响我国夏季气候异常。
文摘This investigation aims to study the El-Niño-Southern Oscillation (ENSO) events in these three phases: El Niño, La Niña, and neutral. Warm and cold events relate to the Spring/Summer seasons. This paper will search for connections between the ENSO events and climate anomalies worldwide. There is some speculation that those events would be necessary for the climate anomalies observed worldwide. After analyzing the data from the reports to the ENSO, it shows almost periodicity from 1950-2023. We emphasized the occurrence of El Niño two years, when it was most prominent, and the climate anomalies (following NOAA maps), 2015 and 2023. The results indicated that the observed climate anomalies couldn’t be linked to the abnormal events observed. The worldwide temperatures in those years enhanced mostly in 2023. It shows an abnormal behavior compared with all the years scrutinized and analyzed since the records began. Therefore, there must be unknown factors beyond ENSO that rule the worldwide temperatures and the climate anomalies observed.
基金supported by National Key Technology Research and Development Program (Grant No. 2007BAC29B02)the National Basic Research Program of China’s 973 Program (Grant Nos.2010CB950502 and 2010CB428904)the project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘In this study, a group of indices were defined regarding intensity (P), area (S) and central position (λc, Фc) of the Aleutian low (AL) in the Northern Hemisphere in winter, using seasonal and monthly mean height field at 1000-hPa. These indices were calculated over 60 winter seasons from 1948/1949 to 2007/2008 using reanalysis data. Climatic and anomalous characteristics of the AL were analyzed based on these indices and relationships between the AL, and general circulations were explored using correlations between indicesP, λc, and Pacific SST, as well as Northern Hemisphere temperature and precipitation. The main results are these: (1) AL is the strongest in January, when the center shifts to the south and west of its climatological position, and it is the weakest in December when the center shifts to the north and east. (2) AL intensity (P) is negatively correlated with its longitude (λc): a deeper low occurs toward the east and a shallower low occurs toward the west. On a decadal scale, the AL has been persistently strong and has shifted eastward since the 1970s, but reversal signs have been observed in recent years. (3) The AL is stronger and is located toward the east during strong E1 Nifio winters and vice versa during strong La Nifia years; this tendency is particularly evident after 1975. The AL is also strongly correlated with SST in the North Pacific. It intensifies and moves eastward with negative SST anomalies, and it weakens and moves westward with positive SST anomalies. (4) Maps of significance correlation between AL intensity and Northern Hemisphere temperature and rainfall resemble the PNA teleconnection pattern in mid-latitudes in the North Pacific and across North America. The AL and the Mongolian High are two permanent atmospheric pressure systems adjacent to each other during boreal winter over the middle and high latitudes in the Northern Hemisphere, but their relationships with the E1 Nifio/La Nifia events and with temperature and precipitat
文摘2021/2022年冬季,赤道中东太平洋海温偏低,导致贵州省气温偏低、降水偏多,但凝冻日数总体偏少,呈前期偏弱后期偏强的阶段性分布特征。利用贵州省84个国家气象观测站逐日观测资料、NCEP/NCAR(National Centers for Environmental Prediction/National Center for Atmospheric Research)再分析资料以及NOAA(National Oceanic and Atmospheric Administration)海温资料等,分别从海温场、高度场、风场、温度场和水汽条件等方面对凝冻阶段性特征成因进行分析。结果表明:高层南支锋区总体呈前期偏弱后期偏强,为贵州省凝冻阶段性特征提供了有利的大尺度环流背景。2022年1月26日之后,对流层低层切变线稳定维持、偏北气流异常强盛使0℃等温线南压明显。同时随着偏南气流持续增强,对流层低层水汽辐合也迅速增强,并维持低层辐合中层辐散的不稳定层结和上升运动,为贵州省凝冻阶段性特征提供了有利的水汽条件。温度场上,前期暖层较为深厚,冷空气势力前期偏弱后期偏强,为贵州省凝冻阶段性特征提供了有利的温度条件。但由于整个冬季无逆温层存在,导致3次区域性凝冻过程强度均偏弱。
基金Supported by the National Natural Science Foundation of China(41575091)National(Key)Basic Research and Development(973)Program of China(2012CB957803)Natural Science Foundation of Jiangsu Province(BK20171230)
文摘The impact of solar activity on climate system is spatiotemporally selective and usually more significant on the regional scale. Using statistical methods and solar radio flux(SRF) data, this paper investigates the impact of the solar11-yr cycle on regional climate of Northeast Asia in recent decades. Significant differences in winter temperature,precipitation, and the atmospheric circulation over Northeast Asia are found between peak and valley solar activity years. In peak years, temperature is higher over vast areas of the Eurasian continent in middle and high latitudes, and prone to producing anomalous high pressure there. Northeast Asia is located to the south of the anomalous high pressure, where the easterlies prevail and transport moisture from the western Pacific Ocean to the inland of East Asia and intensify precipitation there. In valley years, temperature is lower over the Eurasian continent and northern Pacific Ocean in middle and high latitudes, and there maintain anomalous low pressure systems in the two regions. Over the Northeast Asian continent, north winds prevail, which transport cold and dry air mass from the high latitude to Northeast Asia and reduce precipitation there. The correlation coefficient of winter precipitation in Northeast China and SRF reaches 0.4, and is statistically significant at the 99% confidence level based on the Student's t-test. The latent heat flux anomalies over the Pacific Ocean caused by solar cycle could explain the spatial pattern of abnormal winter precipitation of China, suggesting that the solar activity may change the climate of Northeast Asia through air–sea interaction.
文摘利用1979~2013年NCEP/NCAR月平均再分析资料及NOAA研究中心的CMAP(CPC Merged Analysis of Precipitation)月平均降水资料,通过定义欧亚—北太平洋间大气质量迁移指数IMAMEP,分析了春季欧亚—北太平洋上空大气质量迁移(MAMEP,Migration of Atmospheric Mass over Regions between Eurasia and North Pacific)的年际变化规律及其与同期中国气候异常的联系。结果表明:在北半球中高纬度存在一个纬向分布的欧亚—北太平洋遥相关型,且其可能对中国同期气候异常的形成具有重要影响。春季MAMEP指数具有显著的长期趋势,同时还具有2~4年及5~7年的振荡周期及明显的年代际变化特征。垂直环流和波动运动对欧亚—北太平洋间大气质量迁移具有重要作用。大气质量在欧亚西部低层异常辐合,高层异常辐散,在中、西太平洋地区低层异常辐散,高层异常辐合,在纬向上构成了顺时针的垂直环流圈,将西北太平洋地区的大气质量变动与欧亚大陆上空的变动联系了起来。另外,来自西欧大陆的波扰能量可传播至北太平洋,有利于这些区域上空位势高度异常扰动的维持。IMAMEP与春季同期降水及地表气温异常关系密切。IMAMEP为正时,东亚以北地区、鄂霍次克海西岸以及西欧沿岸降水显著减少,欧亚西部及我国华北地区降水显著增加。850 h Pa上西伯利亚受反气旋式环流控制,太平洋上空受气旋式环流控制,引起欧亚大陆北部地表显著增温,西伯利亚以东、我国东北、华北—江淮地区及韩国、日本南部地表显著降温。西欧—我国西北部分地区大面积显著降温现象与这两个地区受异常反气旋东侧的偏北气流影响有关。这些结果有利于人们更深刻认识区域春季气候异常形成机理。