全球年平均人为热释放气候强迫的估算

利用能源经济领域具有权威性的英国石油公司(BP)世界能源统计资料和联合国人口统计资料,通过一些简单的数值计算,初步估算了人为热释放的全球气候强迫。结果表明:当前(2008年)全球年平均人为热释放的气候强迫还不是很大,约为0.031W/m2;但随着人口及能源消费总量的增加,未来人为热释放产生的全球年平均气候强迫将有可能达0.30W/m2。     

Changes in the Tropical Cyclone Genesis Potential Index over the Western North Pacific in the SRES A2 Scenario

The Tropical Cyclone Genesis Potential Index (GPI) was employed to investigate possible impacts of global warming on tropical cyclone genesis over the western North Pacific (WNP). The outputs of 20th century climate simulation by eighteen GCMs were used to evaluate the models’ ability to reproduce tropical cyclone genesis via the GPI. The GCMs were found in general to reasonably reproduce the observed spatial distribution of genesis. Some of the models also showed ability in capturing observed temporal vari...     

The Discovery of Late Ordovician Granodiorite in the Xiemisitai Area, Xinjiang and its Geological Significance

<正>Objective The Xiemisitai area located in the northern part of the West Junggar,Xinjiang is an important component of the central Asian metallogenic domain.Recent studies show that the formation age of acid volcanic and intrusive rocks in the Xiemisitai area mainly ranges from the Late Silurian to the Early Devonian,and the age of the mineralized dacite porphyry is Early Silurian.These rocks are the     

我国极端高温事件的年代际变化及其与大气环流的联系

利用1957～2004年全国181个气象台站观测逐日最高气温,分析了我国年平均极端高温事件(Ex-treme Hot Events,EHE)日数、强度、最早发生日期(EHE Onset Date,EHE-OD)和最迟发生日期(EHETermination Date,EHE-TD)的气候态及年代际变化的时空特征.气候态分...     

中国区域人为热释放的气候强迫

研究了1978～2008年中国地区及各省、市、自治区、特别行政区人为热释放造成的气候强迫与不同地区间的人口、能源消费状况和人为热释放的气候强迫的关系,并试图对未来人为热释放的气候强迫做出预估.结果表明,近30年中国地区平均人为热释放造成的气候强迫迅速增加,1978年其值约为0.07 W·m-2,但2008年则增至0.28 W·m-2.另外,中国人为热释放的气候强迫呈典型地域分布特征,华北、华东、华中和华南等经济发达地区明显高于周围其他地区,而西北地区整体上来说则很小,地区分布很不均匀.这种不均匀分布的特征,可能对区域气候、甚至全球气候造成影响.     

Infrared Imaging Solar Spectrograph At Purple Mountain Observatory

Since 1986, we have made some improvements to the multichannel solar spectrograph at Purple Mountain Observatory (PMO) step by step, and now we have developed and added to it a multichannel infrared imaging solar spectrograph. The original spectrograph can be used to observe simultaneously solar activity at 9 wave bands including Caii H and K line, Mgi b line, Hei D3 line and H through H. The newly developed infrared imaging spectrograph can work in three wavelengths, i.e., Hei 10830 Å, Caii 8542 Å, and H. We replaced plates in the original system with CCDs and placed an image reducer before each CCD in order to match the CCD pixel size. The dispersions for Hei 10830 Å, Caii 8542 Å, and H of the new imaging solar spectrograph are 0.0693 Å, 0.0767 Å, and 0.0754 Å per CCD pixel respectively, and each vertical CCD pixel represents 0.34 arc sec of solar disk. We can obtain the line-center and off-band intensities of the three lines and the intensities of continua adjacent to these lines through the new instrument. We can also acquire velocity maps and line profiles. Therefore, it is specially suitable for two-dimensional (2D) spectroscopic observations of solar flares and active regions. We carry out scanning observation by rotating the second mirror of the coelostat system. In this paper, we introduce the improvements we made and the new imaging solar spectrograph. Some observation results are also presented in this article.     

印度洋偶极子对中国南海夏季西南季风水汽输送的影响

利用NCEP/NCAR再分析资料和中科院大气物理研究所PIAP3大气环流模式,分析了印度洋偶极子对夏季中国南海西南季风水汽输送的影响。结果表明,印度洋偶极子正位相期间夏季中国南海西南水汽输送较强,负位相期间则较弱。原因可归结为以下:正位相期间,MJO（Madden-Julian Oscillation）多活动于热带西印度洋,其向东传播受到阻碍,但经向传播明显,通常可传播至孟加拉湾地区,同时PIAP3显示印度洋季风槽位置偏北,且印尼以西过赤道气流较强,从而使得这一地区气旋性环流得到建立与加强。孟加拉湾地区对应着较强的对流活动以及深厚积云对流加热,从而通过对流加热的二级热力响应使西太平洋副热带高压位置向北推进,进而使得南海地区西南季风水汽输送得到建立与加强。在此期间孟加拉湾、中南半岛至南海地区对流活动较强,而苏门答腊沿岸对流活动受到抑制,由此增强了Reverse-Hadley环流,使低层经向风较强,进而增强了南海西南季风的水汽输送,PIAP3大气环流模式证实了Reverse-Hadley环流的增强。负位相期间,MJO多活动于热带东印度洋,在东传过程中受到Walker环流配置影响,在140°E赤道附近形成东西向非对称积云对流加热热源,其东侧Kelvin波响应加强了东风异常并配合副热带高压南缘东风压制了中国南海的西南季风水汽输送。在此期间,MJO在南海地区的经向传播较强,但经向传播常止步于南海地区15°N附近,虽携带大量水汽,但深厚积云对流强烈地消耗水汽使大气中水汽含量降低,PIAP3大气环流模式证实负位相期间深厚积云对流对水汽消耗加大,从而使得负位相期间南海地区水汽含量与正位相期间大体相近,但由于经向风不足使水汽向北输送较弱。     

The China Multi-Model Ensemble Prediction System and Its Application to Flood-Season Prediction in 2018

Multi-model ensemble prediction is an effective approach for improving the prediction skill short-term climate prediction and evaluating related uncertainties. Based on a combination of localized operation outputs of Chinese climate models and imported forecast data of some international operational models, the National Climate Center of the China Meteorological Administration has established the China multi-model ensemble prediction system version 1.0 (CMMEv1.0) for monthly-seasonal prediction of primary climate variability modes and climate elements. We verified the real-time forecasts of CMMEv1.0 for the 2018 flood season (June-August) starting from March 2018 and evaluated the 1991-2016 hindcasts of CMMEv1.0. The results show that CMMEv1.0 has a significantly high prediction skill for global sea surface temperature (SST) anomalies, especially for the El Nino-Southern Oscillation (ENSO) in the tropical central-eastern Pacific. Additionally, its prediction skill for the North Atlantic SST triple (NAST) mode is high, but is relatively low for the Indian Ocean Dipole (IOD) mode. Moreover, CMMEv1.0 has high skills in predicting the western Pacific subtropical high (WPSH) and East Asian summer monsoon (EASM) in the June-July-August (JJA) season. The JJA air temperature in the CMMEv1.0 is predicted with a fairly high skill in most regions of China, while the JJA precipitation exhibits some skills only in northwestern and eastern China. For real-time forecasts in March-August 2018, CMMEv1.0 has accurately predicted the ENSO phase transition from cold to neutral in the tropical central-eastern Pacific and captures evolutions of the NAST and IOD indices in general. The system has also captured the main features of the summer WPSH and EASM indices in 2018, except that the predicted EASM is slightly weaker than the observed. Furthermore, CMMEv1.0 has also successfully predicted warmer air temperatures in northern China and captured the primary rainbelt over northern China, except that it predicted much more precipitation in the middle and lower reaches of the Yangtze River than observation.     

Debris flows in the Lushan earthquake area: formation characteristics,rainfall conditions,and evolutionary tendency

Debris flows often occur in the mountainous watersheds of earthquake-affected areas, and in the Lushan earthquake area of southwestern China, they have become a significant hazard. In this study, the influencing factors and spatial distribution of debris flows were analyzed through a review of their occurrence history. Debris flows are mainly distributed in the northwestern part of the study area, which hosts the greatest density of active faults. The debris flows are generally formed by the ‘progressive bulking’ effect in channels, and deep incision, lateral erosion, and blockage breaking are common processes that amplify the magnitude of such debris flows. Rainfall thresholds for different types of debris flow were proposed to explain the spatial differences between debris-flow regions, and the temporal variations of those thresholds highlighted how the rainfall conditions required for the occurrence of debris flows have changed. Natural vegetation recovery, reduction in the availability of solid material, and artificial debris-flow control projects play important roles in raising the threshold of the rainfall conditions required for triggering debris flows.

     

盆地对三分量地震动持时的影响初探

利用关东盆地及其周边KiK-net台网井上台站记录的2004—2017年15次中强地震（矩震级为5.1～6.9级）构建三分量记录显著持时Ds_5-95数据库。针对该数据库,基于残差分析方法和3种水平向地震动持时参数预测方程,计算并给出事件间残差和事件内残差及其随不同类别参数的变化。在此基础上,初步探讨了水平向地震动持时预测方程应用于预测竖向地震动持时的可行性及盆地对三分量地震动持时的影响。研究结果表明,对于震源距和场地V_S30相当的情况,盆地内台站持时普遍大于盆地外台站持时,盆地内、外台站竖向地震动持时均大于水平向地震动持时;3种预测方程均可实现对盆地外台站水平向地震动Ds_5-95的合理估计,但在一定程度上低估了盆地内台站的水平向地震动Ds_5-95;3种预测方程均无法直接应用于竖向地震动持时预测。