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1.
The work presents microparticle concentrations in snowpits from the East Rongbuk Glacier on Mt. Qomolangma (Everest) (ER) (28.02°N, 86.96°E, 6536 m a.s.l.), the Zhadang Glacier on Mt. Nyainqentanglha (NQ) (30.47°N, 90.65°E, 5800m a.s.l.), and the Guoqu Glacier on Mt. Geladaindong (GL) (33.95°N, 91.28°E, 5823m a.s.l.) over the Tibetan Plateau (TP). Variations of microparticle and major ions (e.g. Mg2+, Ca2+) concentrations in snowpits show that the values of the microparticles and ions in the non-monsoon seasons are much higher than those in the monsoon seasons. Annual flux of microparticle deposition at ER is lower than those at NQ and GL, which could be attributed to the long distance away from the possible dust source regions as well as the elevation for ER higher than the others. Compared with other remote areas, microparticle concentrations in the southern TP are much lower than those in the northern TP, but still much higher than those in Greenland and Antarctica. The seasonal and spatial microparticle variations are clearly related to the variations of atmospheric circulation according to the air mass 5-day backward trajectory analyses of HYSPLIT Model. Resultingly, the high microparticle values in snow are mainly attributed to the westerlies and the strong dust storm outbreaks on the TP, while the monsoon circulation brings great amount of precipitation from the Indian Ocean, thus reducing in the aerosol concentrations.  相似文献   

2.
Mt.Everest （27°54＇ N,86°54＇ E）,the highest peak,is often referred to as the earth＇s ＇third＇ pole,at an elevation of 8844.43 m. Due to the difficult logistics in the extreme high elevation regions over the Himalayas,observational meteorological data are very few on Mt. Everest. In 2005,an automatic weather station was operated at the East Rongbuk glacier Col of Mt. Everest over the Himalayas. The observational data have been compared with the reanalysis data from the National Centers for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR）,and the reliability of NCEP/NCAR reanalysis data has been investigated in the Himalayan region,after the reanalyzed data were interpolated in the horizontal to the location of Mt. Everest and in the vertical to the height of the observed sites. The reanalysis data can capture much of the synoptic-scale variability in temperature and pressure,although the reanalysis values are systematically lower than the observation. Furthermore,most of the variability magnitude is,to some degree,underestimated. In addition,the variation extracted from the NCEP/NCAR reanalyzed pressure and temperature prominently appears one-day lead to that from the observational data,which is more important from the standpoint of improving the safety of climbers who attempt to climb Mt. Everest peak.  相似文献   

3.
Introduction The Loess Plateau is located in the upper and middle reaches of the Yellow River, among the western Taihang Mt, eastern Riyue-Helan Mt, northern Qinling Mt, and southern Yinsan Mt (from 100°54′to 114°33′E and 33°43′to 41°31′N; Figure 1). It covers a total area of 624,000 km2. The Loess Plateau of China has drawnworldwide attention in geographical research for its unique morphological features, abundant nature resources, most serious soil erosion, as well as its pot…  相似文献   

4.
Location and Environment The Gongga Alpine Ecosystem Observation Station (GAEOS) is located in the Hailuogou Valley (29o36扤,101o53扙), on the eastern slope of Mt. Gongga. It consists of the base station (1600 m a.s.l.) in Moxi Town, sub-alpine observatory (3000m a.s.l.) and chemical analysis center in Chengdu. Mt. Gongga with its summit of 7556 m is the highest peak of the Hengduan Mountains. There are remarkable differences in weather, soil and vegetation from low to high along the…  相似文献   

5.
Fishery biology of jumbo flying squid Dosidicus gigas off Costa Rica Dome   总被引：1，自引：0，他引：1  
The jumbo flying squid(Dosidicus gigas) population was surveyed with the help of Chinese squid jigging vessels off the Costa Rica Dome(4°–11°N, 90°–100°W) in 2009 and 2010. The daily catch of D. gigas in the two survey cruises ranged from 0 to 5.5 t and was mostly obtained from the areas bounded by 6°–9°N and 91°–94°W and by 6°30′–7°30′N and 96°–97°W. The sea surface temperature in the areas yielding the most catch ranged from 27.5 to 29℃. The sex ratio of the total catch was 3.75:1(female: male). The mantle length of the squid ranged from 211 to 355 mm(male) and from 204 to 429 mm(female) with an average of 297.9 and 306.7 mm, respectively. In the relationship of the mantle length(mm) and body weight(g) of the squid, there was no significant difference between sexes. The female and male were at a similar maturity, and most individuals are maturing or have matured with a few females being spent. The size(mantle length) and age at the first sexual maturity were 297 mm and 195 d in females, and less than 211 mm and 130 d in males, respectively. Most of the sampled stomachs(70.6%) had no food remains. The major preys of the squids were fish, cephalopods and crustaceans, with the most abundant Myctophum orientale and D. gigas. The preys in more than 65% of the non-empty sampled stomachs evidenced the cannibalism of D. gigas. The results improved current understanding of the fishery biology of D. gigas off the Costa Rica Dome, which may facilitate the assessment and management of relative fishery resources.  相似文献   

6.
Mt. Everest is often referred to as the earth's 'third' pole. As such it is relatively inaccessible and little is known about its meteorology. In 2005, an automatic weather station was operated at North Col (28°01' 0.95" N, 86°57' 48.4" E, 6523 m a.s.l.) of Mt. Everest. Based on the observational data, this paper compares the reanalysis data from NCEP/NCAR (hereafter NCEP-Ⅰ) and NCEP-DOE AMIP-Ⅱ (NCEP-Ⅱ), in order to understand which reanalysis data are more suitable for the high Himalayas with Mt. Everest region. When comparing with those from the other levels, pressure interpolated from 500 hPa level is closer to the observation and can capture more synoptic-scale variability, which may be due to the very complex topography around Mr. Everest and the intricately complicated orographic land-atmosphere-ocean interactions. The interpolation from both NCEP-Ⅰ and NCEP-Ⅱ daily minimum temperature and daily mean pressure can capture most synoptic-scale variability (r>0.82, n=83, p<0.001). However,there is difference between NCEP-Ⅰ and NCEP-Ⅱ reanalysis data because of different model parameterization. Comparing with the observation, the magnitude of variability was underestimated by 34.1%, 28.5 % and 27.1% for NCEP-Ⅰ temperature and pressure, and NCEP-Ⅱ pressure, respectively, while overestimated by 44.5 % for NCEP-Ⅱ temperature. For weather events interpolated from the reanalyzed data, NCEP-Ⅰ and NCEP-Ⅱ show the same features that weather events interpolated from pressure appear at the same day as those from the observation, and some events occur one day ahead, while most weather events interpolated from NCEP-Ⅰ and NCEP-Ⅱ temperature happen one day ahead of those from the observation, which is much important for the study on meteorology and climate changes in the region, and is very valuable from the view of improving the safety of climbers who attempt to climb Mt. Everest.  相似文献   

7.
The characteristics of the permafrost along National Highway No. 214(G214) in Qinghai province(between kilometer markers K310 and K670),including the distribution patterns of permafrost and seasonally frozen ground(SFG), ground ice content and mean annual ground temperature(MAGT), were analyzed using a large quantity of drilling and measured ground temperature data. Three topographic units can be distinguished along the highway: the northern mountains, including Ela Mountain and Longstone Mountain; the medial alluvial plain and the southern Bayan Har Mountains.The horizontal distribution patterns of permafrost can be divided into four sections, from north to south: the northern continuous permafrost zone(K310-K460),the island permafrost zone(K460-K560), the southern continuous permafrost zone(K560-K630),and the discontinuous permafrost zone(K630-K670).Vertically, the permafrost lower limits(PLLs) of the discontinuous zone were 4200/4325 m, 4230/4350 m,and 4350/4450 m on the north-facing/south-facing slopes of Ela Mountain, Longstone Mountain and Bayan Har Mountains, respectively. The permafrost was generally warm, with MAGTs between-1.0°C and0°C in the northern continuous permafrost zone,approximately-0.5°C in the island permafrost zone,between-1.5°C and 0°C in the southern continuous permafrost zone, and higher than-0.5°C in the discontinuous permafrost zone. In contrast, the spatial variations in ground ice content were mainly controlled by the local soil water content and lithology.The relationships between the mean annual air temperature(MAAT) and the PLLs indicated that the PLLs varied between-3.3°C and-4.1°C for the northern Ela and Longstone Mountains and between-4.1°C and-4.6°C in the southern Bayan Har Mountains.  相似文献   

8.
Hu  Shijian  Liu  Lingling  Guan  Cong  Zhang  Linlin  Wang  Jianing  Wang  Qingye  Ma  Jie  Wang  Fujun  Jia  Fan  Feng  Junqiao  Lu  Xi  Wang  Fan  Hu  Dunxin 《中国海洋湖沼学报》2020,38(4):1092-1107
Near-inertial oscillation is an important physical process transferring surface wind energy into deep ocean.We investigated the near-inertial kinetic energy(NIKE) variability using acoustic Doppler current profiler measurements from a mooring array deployed in the tropical western Pacific Ocean along130°E at 8.5°N,11°N,12.6°N,15°N,and 17.5°N from September 2015 to January 2018.Spatial features,decay timescales,and significant seasonal variability of the observed NIKE were described.At the mooring sites of 17.5°N,15°N,and 12.6°N,the NIKE peaks occurred in boreal autumn and the NIKE troughs were observed in boreal spring.By contrast,the NIKE at 11°N and 8.5°N showed peaks in winter and troughs in summer.Tropical cyclones and strong wind events played an important role in the emergence of high-NIKE events and explained the seasonality and latitudinal characteristics of the observed NIKE.  相似文献   

9.
CAUSES AND COUNTERMEASURES FOR CHAOHU LAKESHORE COLLAPSE   总被引：3，自引：0，他引：3  
1INTRODUCTIONChaohu Lake (30°25′28"-31°43′28"N, 117°16′54"-117°51′46"E) is located in the center of Anhui Provin-ce, and is one of the five biggest freshwater lakes inChina. The lakeshore′s collapse is one of the main envi-ronmental hazards of th  相似文献   

10.
Wang  Yu  Li  Yuanlong  Wei  Chuanjie 《中国海洋湖沼学报》2020,38(1):16-29
Subtropical sea surface salinity(SSS) maximum is formed in the subtropical South Indian Ocean(SIO) by excessive evaporation over precipitation and serves as the primary salt source of the SIO. Spaceborne SSS measurements by Aquarius satellite during September 2011–May 2015 detect three disconnected SSS maximum regions(35.6) in the eastern(105°E–115°E, 38°S–28°S), central(60°E–100°E, 35°S–25°S), and western(25°E–40°E, 38°S–20°S) parts of the subtropical SIO, respectively. Such structure is however not seen in gridded Argo data. Analysis of Argo pro?le data con?rms the existence of the eastern maximum patch and also reveals SSS overestimations of Aquarius near the western and eastern boundaries. Although subjected to large uncertainties, a mixed-layer budget analysis is employed to explain the seasonal cycle of SSS. The eastern and central regions reach the highest salinity in February–March and lowest salinity in August–September, which can be well explained by surface freshwater forcing(SFF) term. SFF is however not controlled by evaporation( E) or precipitation( P). Instead, the large seasonal undulations of mixed layer depth(MLD) is the key factor. The shallow(deep) MLD in austral summer(winter) ampli?es(attenuates) the forcing ef fect of local positive E-P and causes SSS rising(decreasing). Ocean dynamics also play a role. Particularly, activity of mesoscale eddies is a critical factor regulating SSS variability in the eastern and western regions.  相似文献   

11.
A non-dimensional relative sensitivity coefficient was employed to predict the responses of reference crop evapotranspiration （ET0） to perturbation of four climate variables in Tao＇er River Basin of the northeastern China. Mean monthly ET0 and yearly ET0 from 1961 to 2005 were estimated with the FAO-56 Penman-Monteith Equation. A 45-year historical dataset of average monthly maximum/minimum air temperature, mean air temperature, wind speed, sunshine hours and relative humidity from 15 meteorological stations was used in the analysis. Results show that： 1） Sensitivity coefficients of wind speed, air temperature and sunshine hours were positive except for those of air temperature of Arxan Meteorological Station, while those of relative humidity were all negative. Relative humidity was the most sensitive variable in general for the Tao＇er River Basin, followed by sunshine hours, wind speed and air temperature. 2） Similar to climate variable, monthly sensitivity coefficients exhibit large annual fluctuations. 3） Sensitivity coefficients for four climate variables all showed significant trends in seasonal/yearly series. Also, sensitivity coefficients of air temperature, sunshine hours and wind speed all showed significant trends in spring. 4） Among all sensitivity coefficients, the average yearly sensitivity coefficient of relative humidity was highest throughout the basin and showed largest spatial variability. Longitudinal distribution of sensitivity coefficients for air temperature, relative humidity and sunshine hours was also found, which was similar to the distribution of the three climate variables.  相似文献   

12.
影响人体体感温度的气象要素主要包括温度、湿度、风以及太阳辐射,依据这些气象要素影响人体体感温度的原理,确定了平均气温与体感温度相同时的临界相对湿度、风速及太阳辐射值.以全国有水平面直接辐射曝辐量观测项目的77个气象台站的历年逐日4次定时观测资料为基础,把相邻两个白昼(夜间)的气温差作为因变量,相对湿度差、风速差、垂直辐射差(白昼)作为自变量,以旬为时问分辨率,建立了逐旬多元回归方程.各地所建立的逐句多元线性拟合方程拟合优度相当高,F统计量检验也充分证明线性回归方程总体成立,从气候意义、统计角度来看该方法都具有充分的可行性.  相似文献   

13.
气象变量常作为重要的影响因子出现在环境污染、疾病健康和农业等领域,而高分辨率的气象资料可作为众多研究的基础数据,对推进相关研究的发展意义重大。本文以中国大陆为研究区域,利用2015年824个气象站点的气温、相对湿度和风速3套数据,结合不同的解释变量组合,分别构建了各自的GAM和残差自编码器神经网络（简称残差网络）模型,以10倍交叉验证判断模型是否过拟合。研究结果表明：① GAM和残差网络方法都不存在过拟合问题,同GAM相比,残差网络显著提高了模型预测的精度（3个气象因素的交叉验证CV R2平均提高了0.21,CV RMSE平均降低了37%）,其中相对湿度模型的提升幅度最大（CV R2:0.85 vs. 0.52,CV RMSE:7.53% vs. 13.59%）;② 残差模型的结果较普通克里格插值结果和再分析资料更接近站点观测数据,表明残差网络可作为高分辨率气象数据研制的可靠方法。此外,研究还发现在相对湿度模型中加入臭氧浓度和气温、在风速模型中加入GLDAS风速再分析资料,可提升模型的性能。  相似文献   

14.
川西高原若尔盖旅游气候资源及旅游舒适期研究   总被引：1，自引：0，他引：1  
利用若尔盖1971-2000年的逐日日照时数、气温、降水量、降水日数、相对湿度、风速、气压等气象资料,用常规统计方法对以上主要旅游气候要素进行月、年变化规律分析,为当地旅游管理部门提供参考,为旅客提供气象服务。统计和分析表明：若尔盖光照资源丰富,日照总时数达到2510h。该地整年气温偏低,月均气温为-10.2℃-10.8℃,年平均气温为0.8℃,而且随着年份的增加,气温呈上升趋势。年降水量为649.1mm,干湿季分明,5-10月降水量占全年降水量的88%,白天降水少并且无大的降水。空气相对湿度与气温的配合让人体感觉比较舒适,风速较小,适合开展旅游活动。该地的最佳旅游舒适期为7、8月,而6月和9月可根据实时天气情况适当安排旅游活动,舒适天数在68天左右,舒适天数随年份呈波动上升趋势。  相似文献   

15.
基于GPRS网络的气象要素自动采集系统设计与应用   总被引：2，自引：0，他引：2  
目前，气象部门探测的气象资料主要包括：气压、温度、湿度、雨量、风速和风向6个要素。传统的采集方式，每隔一个小时人工采集一次，数据传输慢、精度低。随着全国气象事业发展纲要的实施，气象仪器的智能化和精确化已经成为必然。气象要素自动采集组网系统分为3个单元：自动采集单元负责探测、传输各种气象要素；数据中心负责与各个采集单元进行双工通信；在Internet上以电子地图方式对区域用户提供查询、打印和数据分析服务。  相似文献   

16.
Abies georgei var. smithii is a dominant species playing an important role in protecting biodiversity and sustaining the forestry ecosystems in Southeastern Tibetan Plateau. Stem sap flows of five different diameters at the breast height(DBH) A. georgei var. smithii samples were monitored continuously with the thermal dissipation probe for the entire growing period in order to understand the water transportation mechanism and the effects of environmental factors on its transpiration and growth. Relative environment factors, temperature and humidity of air, photosynthetically active radiation, rainfall, and wind speed, soil moisture, etc. were measured by the automatic weather stations. Diurnal and seasonal variations in sap flow rate with the different stem diameters and their correlations with meteorological factors were analyzed. The diurnal change in sap flow velocity showed a single-peak curve at the daily time scale, whereas a lower sap flow velocity can be observed in the largest DBH sample tree at night. The maximum average velocity was observed in August, whereas the minimum velocity was observed in January, and a large amount of water evaporated in summer owing to the higher sap flow velocity. In addition, sap flow velocity was closely related to changes in the micrometeorological factors, with average sap flow velocity showing significant linear correlations with air temperature, photosynthetically active radiation, rainfall, and vapor pressure deficit of air and soil moisture. Therefore, some measures, improving the light and temperature conditions, should be taken for protecting A. georgei var. smithii population in the Tibetan Plateau.  相似文献   

17.
近年来,空气质量问题日渐突出,大气污染已严重影响了人们的身体健康和日常生活。为了探究成都市近年来的大气污染状况,分析大气颗粒物浓度的时空变化特征及其控制性因子,本文利用2016年成都市逐小时PM_(2.5)监测数据,分析成都市PM_(2.5)浓度时空变化特征,探索气象因子与城市空间形态因子(建筑错落度)对PM_(2.5)浓度变化的影响。结果表明:(1)成都市PM_(2.5)浓度的日变化特征表现为城市中心具有"单峰单谷"特征,而城市郊区日变化特征不明显。且城市中心PM_(2.5)浓度空间变化特征整体表现为由西北向东南逐渐减小的趋势。(2)从全年来看,成都市PM_(2.5)浓度与气温和风速均呈显著负相关,与海平面气压呈显著正相关,而与相对湿度的相关性不明显。(3)PM_(2.5)浓度日间变化率与城市空间形态因子的相关性较强,建筑错落度越高,PM_(2.5)浓度下降越快。  相似文献   

18.
选取广东省86个气象观测站的观测资料,采用气候趋势分析和通径分析方法,对广东省1961～2003年小型蒸发皿蒸发量及其相关气象影响因子进行了分析。结果表明:虽然汛期广东省整体平均蒸发量呈下降趋势,前汛期、后汛期线性倾向率分别为-15.86 mm/10a和-13.79 mm/10a;但变化趋势在广东省内空间分布并不均匀,前汛期、后汛期粤东、中部部分地区分别有16、12个站呈上升趋势;前汛期6种气象因子单独对蒸发的决定程度按大小依次为:日照时数>气温>风速>降水>饱和差>气温日较差,后汛期6种气象因子单独对蒸发的决定程度按大小依次为:日照时数>降水>饱和差>风速>气温>气温日较差,整个汛期日照时数与其它各要素的协同作用对蒸发皿蒸发量的决定作用都很大。日照时数和风速总体上的下降是导致广东省汛期蒸发皿蒸发量逐年减少的重要原因。  相似文献   

19.
为了更好地发展旅游事业,在对马尔康旅游资源做出具体规划的同时,对当地的气候资源特征进行分析与评价。利用马尔康县气象站1966~2005年逐日气温、相对湿度、风速、降水量等观测资料,计算当地温湿指数、风寒指数、着衣指数、综合舒适指数等,进而对旅游气候舒适度进行定量分析与评价。研究结果表明:(1)马尔康地区温湿指数和风寒指数分别在7、8月份达最大值,着衣指数在7月份达最小值,人体在7月份感觉最舒适;(2)40a间,马尔康地区温湿指数,风寒指数和着衣指数总体变化较稳定,个别年份波动较大;(3)1966~1990年,舒适天数基本在125d左右波动;受全球变暖影响,1990~2005年马尔康舒适天数呈明显波动上升趋势。这说明马尔康夏季为最适宜旅游季节,全年大概有120d非常适宜旅游,旅游资源丰富,且气候变化对当地旅游资源开发有明显促进作用。  相似文献   

20.
This study analyzed the spatio-temporal variability of air quality data for six standard air pollutants(Particulate Matter 2.5(PM_(2.5)), Particulate Matter 10(PM_(10)), SO_2, NO_2, CO, and O_3) in the Sichuan Basin(SCB), China from 2015 to 2018 in relation to the formation of haze using conventional meteorological data(temperature, wind speed, and relative humidity), satellite data(fire point data, vertical profiles of aerosol subtypes, and aerosol optical depth), planetary boundary layer height, and backward trajectories. The results indicated that the spatio-temporal evolution of the air quality index(AQI) had notable seasonality for the pollution severity in descending order: winter, spring, summer, and autumn. Autumn and winter severe haze events occurred in November and January, respectively, and were caused by higher local pollution emissions under stagnant air conditions. Spring severe haze events occurred in May and were caused by dust from Northwest China and local regions. Severe summer haze events occurred in July and were caused by local burning. Therefore, the analyses showed that local burning, stagnant meteorological conditions, air mass transport and anthropogenic pollution emissions played a key role in haze in the SCB. This study provides scientific insights for fully analyzing heavy air pollution in SCB, China, and also provides a scientific basis for pollution research in regions of complex terrain as basins and mountains.  相似文献   

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