期刊文献+
共找到175篇文章
< 1 2 9 >
每页显示 20 50 100
Predictions of El Nino,La Nina and Record Low Chicago Temperature by Sunspot Number
1
作者 Tai-Jin Kim 《Natural Science》 2019年第6期204-220,共17页
The El Nino Index, defined as 4 intensities (very strong, strong, moderate, weak) in Oceanic Ni&#241;o Index (ONI), was positively correlated with the average sunspot number at each intensity. The La Ni&#241;a... The El Nino Index, defined as 4 intensities (very strong, strong, moderate, weak) in Oceanic Ni&#241;o Index (ONI), was positively correlated with the average sunspot number at each intensity. The La Ni&#241;a Index, defined as 3 intensities (strong, moderate, weak) in ONI, was negatively correlated with the average sunspot number from 1954 to 2017. It appears that very strong El Ni&#241;o events occur frequently during the maximal sunspot number while strong La Ni&#241;a events more often occur during the minimal sunspot number. Since greenhouse-gas is continuously increased, it is therefore proposed that the maximal sunspot number is a major parameter for prediction of El Ni&#241;o while the minimal sunspot number applies in the same way for La Ni&#241;a. El Nino/La Nina events can be classified as four typical cases depending upon the submarine volcanic activities at seamounts in Antarctica and South America. The Sea Surface Temperature (SST) of the South and Central Americas are warmer than SST of East Australian Current (EAC), due to the strong volcanic eruptions in the Seamounts and the Ridges in South and Central Americas. This results in the Central Pacific Current (CPC) flowing from east to west due to the second law of thermodynamics for thermal flow from hot source to cold sink. In contrast the opposite direction is made if SST in EAC is warmer than SST in the Central/South American Seamounts and Ridges, due to the strong volcanic eruptions in the Antarctic Seamounts and Ridges. Chicago was selected as a case study for the relationship between extreme cold weather conditions and minimal sunspot number. Previous attempts at predicting weather patterns in Chicago have largely failed. The years of the record low temperatures in Chicago were significantly correlated with the years of the minimal sunspot number from 1873 to 2019. It is forecast that there may occur a weak La Ni&#241;a in 2019 and another record low temperature in Chicago in January of 2020 due to the phase of the minimal sunspot number in 2019. It may be possible to predict very strong El Nino events with the year of maximal sunspot number as El Ni&#241;o Index (R2 = 0.7363) and the years of strong volcanic eruption in the Galapagos Hot Spot (GHS) (R2 = 0.9939), respectively. An El Ni&#241;o event is thus expected during the year of strong volcanic eruption in the GHS. Strong La Ni&#241;a events can be expected during the year of minimal sunspot number with La Ni&#241;a Index (R2 = 0.9922). Record low temperatures in Chicago can be also predicted (R2 = 0.9995) during the year of the minimal sunspot number, as was recently the case in January, 2019. 展开更多
关键词 Prediction El Nino La Nina record Low Chicago temperature Sunspot Number
下载PDF
Updated Homogenized Chinese Temperature Series with Physical Consistency 被引量:5
2
作者 LI Zhen YAN Zhong-Wei WU Hong-Yi 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第1期17-22,共6页
Most methods of homogenization of climate data are applied to time series of a single variable, such as daily maximum temperature(Tmax) or daily minimum temperature(Tmin). Consequently, the physical relationship among... Most methods of homogenization of climate data are applied to time series of a single variable, such as daily maximum temperature(Tmax) or daily minimum temperature(Tmin). Consequently, the physical relationship among different variables, e.g., Tmax>Tmin, may be distorted after homogenization of climate series of individual variables. The authors develop a solution to improve consistency among diurnal temperature records, while using the Multiple Analysis of Series for Homogenization(MASH) method to homogenize the observation series of daily mean temperature(Tm), Tmin, and Tmax at 545 stations in China for the period 1960–2011, called CHTM2.0. In the previous version of this homogenized dataset based on MASH(CHTM1.0) for the period 1960–2008, there are a few records(0.039% of the total) that are physically inconsistent. For developing CHTM2.0, the authors apply additional adjustments for each day with inconsistent temperature records, in order to hold Tmax>Tm>Tmin. Although the additional adjustments are barely influential for estimating long-term climate trends in China as a whole(because very few records are additionally adjusted), the newly introduced solution improves the physical consistency throughout the dataset. It is also helpful for developing more reasonable homogenized climate datasets with regard to physical consistency among multiple variables. Based on CHTM2.0, the annual Tmax/Tm/Tmin series averaged over China for the period 1960–2011 show significant warming trends of about 0.19/0.25/0.34°C per decade, respectively. Large warming trends of up to 0.425/0.596/ 0.704°C per decade occur in northeastern and northwestern China. 展开更多
关键词 DIURNAL temperature recordS HOMOGENIZATION physica
下载PDF
Average Annual Temperature Changes in the Holocene in China
3
作者 BI Fuzhi YUAN Youshen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第3期321-328,共8页
Abstract: In 1876 Blytt proposed a post-glacial climatic classification, maintaining that the then temperature fluctuated 1–2°C higher or lower than that today. Lamb (1969) held that in Europe “the axis of the ... Abstract: In 1876 Blytt proposed a post-glacial climatic classification, maintaining that the then temperature fluctuated 1–2°C higher or lower than that today. Lamb (1969) held that in Europe “the axis of the subtropical high pressure belt was generally displaced north by about 10° latitudes” during the Hypsithermal and that the temperature was three to six times higher than that in the postglacial period. 展开更多
关键词 Holocene temperature of China range of average annual temperature changes a cycle of about 500 years Hypsithermal historical records beach rock tropical fossil animal
下载PDF
Multi-channel retarding field analyzer for EAST
4
作者 M HENKEL D HOSCHEN +8 位作者 Y LIANG Y LI S C LIU D NICOLAI N SANDRI G SATHEESWARAN N YAN H X ZHANG the EAST team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第5期1-5,共5页
A multi-channel retarding field analyzer(MC-RFA) including two RFA modules and two Langmuir probes to measure the ion and electron temperature profiles within the scrape-off layer was developed for investigations of... A multi-channel retarding field analyzer(MC-RFA) including two RFA modules and two Langmuir probes to measure the ion and electron temperature profiles within the scrape-off layer was developed for investigations of the interplay between magnetic topology and plasma transport at the plasma boundary.The MC-RFA probe for the stellarator W7-X and first measurements at the tokamak EAST was designed.The probe head allows simultaneous multichannel ion temperature as well as for electron temperature measurements.The usability for radial correlation measurements of the measured ion currents is also given. 展开更多
关键词 retarding field analyzer multi-channel EAST ion temperature DIAGNOSTIC
下载PDF
Applicability of initial optimal maternal and fetal electrocardiogram combination vectors to subsequent recordings
5
作者 闫华文 黄晓林 +3 位作者 肇莹 司峻峰 刘铁兵 刘红星 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期639-645,共7页
A series of experiments are conducted to confirm whether the vectors calculated for an early section of a continuous non-invasive fetal electrocardiogram (fECG) recording can be directly applied to subsequent sectio... A series of experiments are conducted to confirm whether the vectors calculated for an early section of a continuous non-invasive fetal electrocardiogram (fECG) recording can be directly applied to subsequent sections in order to reduce the computation required for real-time monitoring. Our results suggest that it is generally feasible to apply the initial optimal maternal and fetal ECG combination vectors to extract the fECG and maternal ECG in subsequent recorded sections. 展开更多
关键词 fetal monitoring real-time multi-channel recording independent component analysis (ICA) peri-odic component analysis
下载PDF
基于NFC的低能耗温湿度记录系统的设计与实现
6
作者 黄勇萍 《信息与电脑》 2023年第3期147-149,共3页
针对现有温湿度监测系统存在成本和能耗偏高等问题,设计一款低能耗的温湿度记录系统。该系统基于近场通信(NearFieldCommunication,NFC)和温湿度传感等技术,硬件部分主要由温湿度传感器模块、NFC标签模块、实时时钟(Real Time Clock,RTC... 针对现有温湿度监测系统存在成本和能耗偏高等问题,设计一款低能耗的温湿度记录系统。该系统基于近场通信(NearFieldCommunication,NFC)和温湿度传感等技术,硬件部分主要由温湿度传感器模块、NFC标签模块、实时时钟(Real Time Clock,RTC)模块以及主控制芯片组成。各模块由锂电池供电,系统提供有效的充电管理,主控制芯片通过输入输出(Input Output,IO)口输出电流给NFC标签等模块供电,以降低能耗。同时,为了方便查阅温湿度记录,设计基于NFC通信的App,可以使用智能手机等便利的移动终端读取温湿度数据,从而实现低成本记录、传输、监测数据。 展开更多
关键词 近场通信(NFC) 温湿度记录 传感器 低能耗
下载PDF
三种插值方法对区域自动气象站日气温缺测数据插补的适用性研究
7
作者 孙越 王海军 +2 位作者 周月华 严婧 刘莹 《暴雨灾害》 2023年第1期97-104,共8页
为解决气温观测记录缺测的问题,选择反距离权重插值(Inverse Distance Weighted,IDW)、普通克里金插值(Ordinary Kriging,OK)和多元线性回归(Multiple Linear Regression,MLR)三种方法,以湖北省2020年为例,对全省逐日平均气温(T)、最高... 为解决气温观测记录缺测的问题,选择反距离权重插值(Inverse Distance Weighted,IDW)、普通克里金插值(Ordinary Kriging,OK)和多元线性回归(Multiple Linear Regression,MLR)三种方法,以湖北省2020年为例,对全省逐日平均气温(T)、最高气温(Tmax)和最低气温(Tmin)进行空间插补,并采用平均绝对误差(Mean Absolute Error,MAE)对3种方法的插补结果进行检验。结果表明:用MLR插补得到的Tmax、Tmin、T的MAE最小,分别为0.41℃、0.31℃和0.20℃,其中T的插补误差在1℃以内的站点比例高达100%;相比IDW和OK,MLR插补结果的MAE空间分布均匀,其不仅随海拔高度变化较小,随季节变化也相对较小。单站试验结果表明,当用于MLR模型的样本数量越多、时间离散度越大时,MLR对气温的插补效果越好。总体上,对日气温缺测数据的插补效果,MLR最优,IDW次之,OK最差;对于建立气象站点长时间连续气温数据集而言,MLR更适合解决区域自动气象站日气温数据缺测问题。 展开更多
关键词 气温 记录缺测 数据插补方法 平均绝对误差 多元线性回归
下载PDF
The temperature record of the Holocene: progress and controversies 被引量:6
8
作者 Juzhi Hou Can-Ge Li Shihyu Lee 《Science Bulletin》 SCIE EI CAS CSCD 2019年第9期565-566,共2页
The pattern of temperature variation during the Holocene, the most recent geological epoch, has been studied intensively, partly because of its significance for the development of human civilization. Prior to the 1980... The pattern of temperature variation during the Holocene, the most recent geological epoch, has been studied intensively, partly because of its significance for the development of human civilization. Prior to the 1980s, based on ice core records in Greenland and Antarctica, the climate of the Holocene was thought to have been rather stable (1)However, this view was challenged by the discovery of a substantial amount of contrary evidence. 展开更多
关键词 The temperature record of the HOLOCENE PROGRESS and CONTROVERSIES
原文传递
基于支持向量机的气温自记纸图像数字化
9
作者 支亚京 汤宁 +3 位作者 吴兴洋 汪华 胡兴炜 张军 《计算机技术与发展》 2023年第10期216-220,共5页
气温自记迹线是记录气温连续变化过程的图像数据,气温自记纸图像数字化是完成纸质气温图像自记纸中字符和迹线信息的数字化处理,建立长序列历史精细化气温数据集。实现气温自记迹线提取和图像数字化,是解决纸质历史气温自记纸保护和应... 气温自记迹线是记录气温连续变化过程的图像数据,气温自记纸图像数字化是完成纸质气温图像自记纸中字符和迹线信息的数字化处理,建立长序列历史精细化气温数据集。实现气温自记迹线提取和图像数字化,是解决纸质历史气温自记纸保护和应用的重要途径。将支持向量机(Support Vector Machine,SVM)和形态学的迹线识别算法集成于气温自记迹线数字化提取软件中,实现了气温自记迹线智能化跟踪提取、质量控制、检查修正以及产品生成。应用结果显示:与前期开发的降水自记迹线、气压自记迹线和EL电接风自记迹线数字化软件相比,该系统首次实现了形变矫正和时间记号线自动识别功能,在自记迹线发生扭曲、歪斜等情况不需人工对自记纸图像重新扫描,可以通过自记纸本身微调自动订正和器差订正,经与A文件中人工整理的气温记录对比,能够满足气温自记纸迹线提取对数据质量和精度的要求。 展开更多
关键词 气温自记迹线 数字化 支持向量机 形态学 智能化跟踪提取 自动订正
下载PDF
不同统计方法对高原和高纬度地区低温极值结果的影响
10
作者 刘溅洪 罗来正 +3 位作者 王健坤 陈雪晴 龙仕腾 吴欣睿 《装备环境工程》 CAS 2023年第12期149-155,共7页
目的研究不同统计方法下高原和高纬度地区低温极值的特征。方法利用高原和高寒地区国家级地面气象观测站2010~2020年间的小时温度数据,研究不同严酷月基准条件下两地低温工作极值的变化情况。结果3种严酷月基准条件下,高原地区低温严酷... 目的研究不同统计方法下高原和高纬度地区低温极值的特征。方法利用高原和高寒地区国家级地面气象观测站2010~2020年间的小时温度数据,研究不同严酷月基准条件下两地低温工作极值的变化情况。结果3种严酷月基准条件下,高原地区低温严酷月相同,工作极值没有发生变化;高纬度地区低温严酷月发生变化,导致工作极值最大差值达到3.2℃。另外,3种条件下高原地区的低温工作极值均高于高纬度地区。结论装备在典型地区服役过程中的环境工作极值统计应明确严酷月基准条件。 展开更多
关键词 高原地区 高纬度地区 低温 严酷月 记录极值 工作极值
下载PDF
Recent temperature increase recorded in an ice core in the source region of Yangtze River 被引量:28
11
作者 KANG ShiChang ZHANG YongJun +4 位作者 QIN DaHe REN JiaWen ZHANG QiangGong Bjorn GRIGHOLM Paul A. MAYEWSKI 《Chinese Science Bulletin》 SCIE EI CAS 2007年第6期825-831,共7页
Interests on climate change in the source region of Yangtze River have been raised since it is a region with the greatest warming over the Tibetan Plateau (TP). A 70-year history of precipitation δ^(18)O has been rec... Interests on climate change in the source region of Yangtze River have been raised since it is a region with the greatest warming over the Tibetan Plateau (TP). A 70-year history of precipitation δ^(18)O has been recovered using an ice core record retrieved in a plat portion of the firn area in the Guoqu Glacier (33°34′37.8″N, 91°10′35.3″E, 5720 m a.s.l.), Mt. Geladaindong (the source region of Yangtze River), in November, 2005. By using a significant positive relationship between ice core δ^(18)O record and summer air temperature (July to September) from the nearby meteorological stations, a history of summer air temperature has been reconstructed for the last 70 years. Summer temperature was relatively low in 1940s and high in 1950s to the middle of 1960s. The lowest temperature occurred in the middle of 1970s. Temperature was low in 1980s and dramatically increased since 1990s, keeping the trend to the begin-ning of the 21st century. The warming rate recorded in the ice core with 0.5℃/10 a since 1970s is much higher that that in the central TP and the Northern Hemisphere (NH), and it becomes 1.1℃/10 a since 1990s which is also higher than these from the central TP and the NH, reflecting an accelerated warm-ing and a more sensitive response to global warming in the high elevation region. 展开更多
关键词 长江源头地区 冰芯 青藏高原 温度升高 Δ^18O记录
原文传递
真空和大气环境干燥箱的温度测量对比
12
作者 乔莉 《环境技术》 2023年第3期128-131,共4页
为保证温度测量结果的精确度,现提出一套行之有效的真空干燥箱温度测量方法。首先,介绍了玻璃液体温度计、温度巡检仪、无线温度压力记录仪、真空干燥箱四种仪器设备。其次,结合真空干燥箱工作原理与接触测温原理,开展温度测量对比试验... 为保证温度测量结果的精确度,现提出一套行之有效的真空干燥箱温度测量方法。首先,介绍了玻璃液体温度计、温度巡检仪、无线温度压力记录仪、真空干燥箱四种仪器设备。其次,结合真空干燥箱工作原理与接触测温原理,开展温度测量对比试验。最后,根据热传递的影响因素,分析温度测量对比结果。结果表明:本文所提出的真空干燥箱温度测量方法具有较高的可靠性和可行性,有效地保证了客户试验数据的完整性和可靠性。希望通过这次研究,为相关人员提供有效的借鉴和参考。 展开更多
关键词 真空干燥箱 大气环境 无线温度压力记录仪 温度测量
下载PDF
Phenological records in Guanzhong Area in central China between 600 and 902 AD as proxy for winter half-year temperature reconstruction 被引量:1
13
作者 LIU YaChen DAI JunHu +2 位作者 WANG HuanJiong YE Yu LIU HaoLong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第9期1847-1853,共7页
Phenological data obtained from historical documents constitute highly important ecological evidence for the pre-instrumental period, and can be used in analyzing climatic change in history. In this study, 87 phenolog... Phenological data obtained from historical documents constitute highly important ecological evidence for the pre-instrumental period, and can be used in analyzing climatic change in history. In this study, 87 phenological records about seasonality of non-biological events(e.g., first frost date), agriculture and ornamental plants(e.g., first flowering date) over 77 years were extracted from historical documents from the Sui and Tang dynasties in China to reconstruct the winter half-year(from October to next April) temperatures in the Guanzhong Area(located in central China) from 600 to 902 AD. Transfer functions between temperature and phenophases with significant correlations were established by using modern observation data. Temperatures from the study period were reconstructed by applying the transfer functions to historical phenological data. The reconstruction indicates that the winter half-year temperatures during 600–902 AD were 0.23°C higher than the reference period(1961–1990). The temperature changed with two distinct stages. During the 600s–800s, temperatures were approximately 0.38°C higher than at present but then temperatures decreased in the subsequent period(800–902 AD). These results are similar to ones from previous studies on the mean temperature and the divisions between warm and cold periods during the study period, though differences were found in the degree of warmness/coldness. This reconstruction provides a valuable contribution to a better understanding of climatic variability during the Sui and Tang dynasties in China. 展开更多
关键词 冬半年温度 关中地区 物候期 中国 历史气候变化 代理 AD 历史文献
原文传递
Temperature insensitive multi-channel light amplification systems on SOI platform
14
作者 周军虎 尤洁 +3 位作者 欧阳昊 苗润林 程湘爱 江天 《Chinese Optics Letters》 SCIE EI CAS CSCD 2022年第8期29-35,共7页
We present a theoretical analysis of a novel multi-channel light amplification photonic system on chip,where the nonlinear Raman amplification phenomenon in the silicon(Si)wire waveguide is considered.Particularly,a c... We present a theoretical analysis of a novel multi-channel light amplification photonic system on chip,where the nonlinear Raman amplification phenomenon in the silicon(Si)wire waveguide is considered.Particularly,a compact and temperature insensitive Mach–Zehnder interferometer filter working as demultiplexer is also exploited,allowing for the whole Si photonic system to be free from thermal interference.The propagation of the multi-channel pump and Stokes lights is described by a rigorous theoretical model that incorporates all relevant linear and nonlinear optical effects,including the intrinsic waveguide optical losses,first-and second-order frequency dispersion,self-phase and cross-phase modulation,phase shift and two-photon absorption,free-carriers dynamics,as well as the inter-pulse Raman interaction.Notably,to prevent excessive drift of the transmission window of the demultiplexer caused by ambient temperature variations and high thermo-optical coefficient of Si,an asymmetric waveguide width is adopted in the upper and lower arms of each Mach–Zehnder interferometer lattice cell.A Chebyshev half-band filter is utilized to achieve a flat pass-band transmission,achieving a temperature sensitivity of<1.4 pm=K and over 100 K temperature span.This all-Si amplifier shows a thermally robust behavior,which is desired by future Si-on-insulator(SOI)applications. 展开更多
关键词 SILICON-ON-INSULATOR multi-channel AMPLIFICATION temperature
原文传递
Rechargeable battery operates at a record low temperature
15
作者 Ping He Haoshen Zhou 《Science Bulletin》 SCIE EI CSCD 2019年第2期76-77,共2页
Commercialized lithium ion batteries(LIBs)using intercalation compounds as electrode materials have found wide applications in kinds of portable devices and electric vehicles(EVs).
关键词 RECHARGEABLE BATTERY operates at a record LOW temperature
原文传递
Determination of seepage velocity in streambed using temperature record of Russian River, USA
16
作者 吴志伟 宋汉周 霍吉祥 《Journal of Hydrodynamics》 SCIE EI CSCD 2013年第3期388-395,共8页
The vertical seepage velocity is an important parameter in the groundwater-surface water (GW-SW) exchange process. It is reported that the periodical fluctuated temperature record of the streambed can be used to det... The vertical seepage velocity is an important parameter in the groundwater-surface water (GW-SW) exchange process. It is reported that the periodical fluctuated temperature record of the streambed can be used to determine the seepage velocity. Based on a 1-D flow and heat transport model with a sinusoidal temperature oscillation at the upstream boundary, a new analytical model is built. This analytical model can be used to determine the seepage velocity from the amplitude ratio of the deep and shallow test points. The process of calculation is discussed. The field data are superimposed by multi-periods, so the spectrum analysis and the data filtering are desirable. For the typical seepage medium, the analytical model is effective to compute the seepage velocity between -2 m/d and 6 m/d by using the record of the daily period fluctuation. The temperature time-series analytical model is used to determine the upwards seepage under the condition that the spacing of test points is small (less than 0.2 m). Lastly, a case study for the Russian River shows that this model is very convenient to determine the temporal changes of the GW-SW exchange. 展开更多
关键词 temperature record groundwater-surface water (GW-SW) exchange STREAMBED analytical model Russian River
原文传递
On Prediction of Record-Breaking Daily Temperature Events 被引量:1
17
作者 封国林 杨杰 +2 位作者 万仕全 侯威 支蓉 《Acta meteorologica Sinica》 SCIE 2009年第6期666-680,共15页
The daily maximum/minimum temperature data at 740 stations in China from 1960 to 2005 were ana-lyzed to reveal the statistical characteristics of record-breaking(RB)daily extreme temperature events in the past 46 yr... The daily maximum/minimum temperature data at 740 stations in China from 1960 to 2005 were ana-lyzed to reveal the statistical characteristics of record-breaking(RB)daily extreme temperature events in the past 46 yr.It is verified that the observational daily extreme temperatures obey the Gaussian distribution. The expected values of RB extreme temperatures were obtained based on both the Gaussian distribution model and the initial condition of observed historical RB high/low temperature events after tedious the-oretical derivation.The results were then compared with those obtained by the iteration computation of the pure theoretical model.The comparison suggests that the results from the former are more consistent with the observations than those from the latter.Based on the above analyses,prediction of future possible RB high/low temperature events is made,and the spatial distributions of maximum/minimum theoretical values of their intensities are also given.It is indicated that the change amplitudes of future extreme temperatures differ evidently from place to place,showing a remarkable regional feature:the future extremely high temperature events will have a strong rising intensity in Southwest China,and a relatively weak rising intensity in western China;while the largest decrease of the future extremely low temperature events will appear in Northeast China and the north of Northwest China,and the decrease will be maintained relatively stable in space in Central China and Southwest China,in comparison with the historical low temperature pattern.Features in the occurrence time of the future RB temperature events are also illustrated. 展开更多
关键词 record-breaking extreme temperature prediction of extreme event
原文传递
Researcher Creates First Temperature Record For The Great Plains
18
作者 张卫红 《科技英语学习》 2007年第3期24-25,共2页
越来越多的学者关注世界各地的温度变化,不光是近年的气温,若干年前甚至史前的温度变化对研究也很重要。美国北部大平原地区一直没有气温记录,但是现在研究人员运用新方法测出了这一地区自12,000年前以来的温度变化。他们是怎么做的呢?
关键词 Researcher Creates First temperature record For The Great Plains 温度变化
原文传递
2006年重庆大旱的历史透视 被引量:17
19
作者 郝志新 葛全胜 +1 位作者 郑景云 李艳旗 《地理研究》 CSCD 北大核心 2007年第4期828-834,共7页
对过去1千年重庆干旱记录分析表明:2006年在重庆及其周边地区所发生的“特大干旱”事件在历史上曾经多次出现,并非历史仅见。这样极端气候事件的发生仅仅是气候波动中一个正常的自然现象,无论是干旱的持续时间、严重程度,还是发生的范... 对过去1千年重庆干旱记录分析表明:2006年在重庆及其周边地区所发生的“特大干旱”事件在历史上曾经多次出现,并非历史仅见。这样极端气候事件的发生仅仅是气候波动中一个正常的自然现象,无论是干旱的持续时间、严重程度,还是发生的范围都可能并未超出气候波动的正常幅度。 展开更多
关键词 重庆 大旱 历史记录 温度变化
下载PDF
40-30kaBP青藏高原及邻区高温大降水事件的特征、影响及原因探讨 被引量:95
20
作者 施雅风 贾玉连 +4 位作者 于革 杨达源 范云崎 李世杰 王云飞 《湖泊科学》 EI CAS CSCD 2002年第1期1-11,共11页
40 - 30kaBP相当于末次冰期大间冰阶或海洋氧同位素MIS3晚期 .青藏高原在岁差周期夏季高太阳辐射作用下 ,据古里雅冰芯与若干孢粉记录指示温度比现在高 2 - 4℃ ,高原及邻区众多大湖的高湖面记录指示大范围降水丰沛 .应用Kutzbach水能... 40 - 30kaBP相当于末次冰期大间冰阶或海洋氧同位素MIS3晚期 .青藏高原在岁差周期夏季高太阳辐射作用下 ,据古里雅冰芯与若干孢粉记录指示温度比现在高 2 - 4℃ ,高原及邻区众多大湖的高湖面记录指示大范围降水丰沛 .应用Kutzbach水能平衡方程推算了封闭湖泊流域 (青海湖、扎布耶 /拉果错、阿克塞钦 /甜水海 )年平均降水可达 6 4 0mm ,5 6 0mm ,2 6 0mm ,分别是现代降水的 1.7倍 ,3倍 ,5倍 .高原及邻区包括祁连山以北和云南部分区域在内的大降水对水系河流产生了重大影响 .高原内部河湖串联 ,水系合并 ;如色林错、班戈错、纳木错串联为高原上最大的内陆水系 ;若尔盖古湖外流并入黄河水系 ;长江上游大水在三峡束狭形成强烈旋涡掏蚀成低于海平面的深槽 ,形成了深槽中、底部的砂砾沉积 .这次高温大降水事件是由高太阳辐射导致的由青藏高原高温热低压加强、热带洋面增暖蒸发强烈、南半球越赤道气流增强共同作用而形成的高原特强夏季风 ,同时极地冰盖迫使西风带南移也可能加强了对高原尤其是西部的降水 .H3事件(2 7kaBP)促进了高温大降水事件的结束 ,H4事件 (35 .5kaBP)则可能短期萎缩了夏季风 ,使高温大降水事件呈现不稳定性特点 . 展开更多
关键词 青藏高原 高湖面记录 高温 水能平衡公式 古里雅冰芯 降水事件 孢粉记录 古气候
下载PDF
上一页 1 2 9 下一页 到第
使用帮助 返回顶部