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1.
Abstract

Since 1969, meteorological and limnological measurements required for evaporation estimates by the energy budget method have been made almost continuously during the open water season at Perch Lake, a small (0.45 km2), shallow (mean depth 2 m) lake on the Canadian Shield. Hydrological measurements required for water budget calculations have been made continuously since 1970. Since ground water input to the lake has been found to be significant, energy budget estimates of evaporation are used in the water budget equation to estimate ground water inflow. Results are summarized as the long‐term averages along with the ranges of variation of the budget components observed during the eleven‐year period.  相似文献   

2.
Ⅰ.INTRODUCTION We have discovered that there exists a good corresponding relationship between theanomalous axes of soil temperature at a depth of 1.6m in winter (December to February) andprecipitations in following flood season (Tang et al., 1982a). We have also designed a simplethermodynamical model and applied it to the forecasting of precipitations in the flood season(Tang et al., 1982 b,c). The practical forecast started from 1975. Before 1980, however, therewere only 40-50 stations in China for measuring the soil temperature at a 1.6m depth. Since1980, the stations have been increased to a total of about 180, but no available mean valueshad been obtained from newly added stations before 1982. Therefore the analysis and map-ping of anomalies of soil temperature was not performed until 1983, and from then on theprecision of analysis has been greatly improved. The following is the actual situation of forecast in five years from 1983 to 1987.  相似文献   

3.
Summary First, the Group Method of Data Handling (GMDH) algorithm, a self-organizing method for constructing higher order regression, is applied to build a model for long-term forecasting. Then, the Group Method of Phase Space Component (GMPSC) model is set up based on chaos theory and GMDH. Several case studies show that both GMDH and GMPSC provide an efficient and potentially useful tool for non-linear time series modeling.Supported by the NKPFR Climate Dynamics and Climate Prediction Theory.  相似文献   

4.
This work focuses on the Late Saalian (140?ka) Eurasian ice sheets?? surface mass balance (SMB) sensitivity to changes in sea surface temperatures (SST). An Atmospheric General Circulation Model (AGCM), forced with two preexisting Last Glacial Maximum (LGM, 21?ka) SST reconstructions, is used to compute climate at 140 and 21?ka (reference glaciation). Contrary to the LGM, the ablation almost stopped at 140?ka due to the climatic cooling effect from the large ice sheet topography. Late Saalian SST are simulated using an AGCM coupled with a mixed layer ocean. Compared to the LGM, these 140?ka SST show an inter-hemispheric asymmetry caused by the larger ice-albedo feedback, cooling climate. The resulting Late Saalian ice sheet SMB is smaller due to the extensive simulated sea ice reducing the precipitation. In conclusion, SST are important for the stability and growth of the Late Saalian Eurasian ice sheet.  相似文献   

5.
This paper presents the earliest temperature observations, scheduled every 3–4 h in the 1654–1670 period, which have been recovered and analysed for the first time. The observations belong to the Medici Network, the first international network of meteorological observations, based on eleven stations, the two main ones being Florence and Vallombrosa, Italy. All observations were made with identical thermometers and operational methodology, including outdoor exposure in the shade and in the sunshine to evaluate solar heating, state of the sky, wind direction and precipitation frequency. This paper will consider only the regular temperature series taken in the shade. The observations were made with the newly invented spirit-in-glass thermometer, also known as Little Florentine Thermometer (LFT). The readings have been transformed into modern units of temperature (°C) and time (TMEC). The LFT has been analysed in detail: how it was made, its linearity, calibration and performances. Since the middle of the LIA, the climate in Florence has shown less than 0.18°C warming. However, although the yearly average showed little change, the seasonal departures are greater, i.e. warmer summers, colder winters and unstable mid seasons. The temperature in the Vallombrosa mountain station, 1,000 m a.m.s.l, apparently rose more, i.e. 1.41°C. A discussion is made on the interpretation of this finding: how much it is affected by climate change or bias. A continuous swinging of the temperature was observed in the Mediterranean area, as documented by the long instrumental observations over the 1654–2009 period. However, changes in vegetation, or exposure bias might have contributed to reduce the homogeneity of the series over the centuries.  相似文献   

6.
Latin America has long played a key role in the global provision of natural resources. Most of the continent's economies are net exporters of low-value, primary products and importers of manufactured goods at a high price. This pattern of specialised trade has highly negative consequences for economic development, the environment, and the local population’s wellbeing. Yet to date, little empirical evidence has been collected on Latin America’s total contribution to the rest of the world's regions in historical perspective. Applying the Material Flow Accounting methodology, this paper estimates the physical and monetary trade of 16 Latin American economies between 1900 and 2016. Our results show that: (i) yearly net exports of materials went from 4 Mt to 610 Mt between 1900 and 2016, and greatly accelerated since the World War II. (ii) Latin America is a net exporter of most types of materials (fossil fuels, non-energy minerals and biomass), so it harbours socio-environmental problems associated with different types of extractivism. (iii) Different regional export patterns exist: Andeans export subsoil (mining and energy carriers) while the rest export soil (land-based products). The countries with the lowest net exports are the smallest in size and with the highest population density. (iv) Europe and the USA have historically received most of the imports, but since the end of the twentieth century, the Southeast Asia region is the biggest importer of materials from Latin America. (v) The price received for exported material is much lower than the price paid for imported material; and (vi) various historical periods can be differentiated regarding the relationship between economic growth and physical trade balance.  相似文献   

7.
Precipitation The estimation of precipitation amounts simply involves the exposure of a container for a given period, usually 24 hours, and the measurement of the depth of collected water (or liquid water equivalent of snow and hail), The amount of rainfall in the 24-hour period is established with the use of a rain measure graduated in inches or mitlimetres, preferably the latter.  相似文献   

8.
余鹤书  晁淑懿 《气象》1981,7(9):42-44
寒潮是我国冬半年一种主要的灾害性天气,寒潮爆发时天气出现急剧变化,气象服务工作中迫切需要准确的寒潮中期预报。寒潮天气过程的一个重要特征,是它与大型环流的急剧变化有关,特别是同西风指数及长波、超长波的变化有密切联系。因此,要做好寒潮中期预报,很关键的一步就是要掌握好与指数循环相联系的大型环流变化过程,尤其是要做好长波、超长波突变的预报。关于这方面的问题,在第三讲中已有所讨论。这里,仅就寒潮中期过程及预报方法,作进一步的讨论。  相似文献   

9.
As water-stressed areas are expanding worldwide due to climate change, water conservation has become an important tool for managing water resources in drought contexts. Within a political ecology framework, our research questions the success story of water conservation. To do so, we conducted a quantitative textual analysis of 520 daily local press articles dealing with drought and water issues in Phoenix and Tucson (Arizona, USA). Using two open-access lexicometric software, our analysis traces the rise of the water conservation narrative in the press. Our results show how newspapers can become an instrument of public policies to work towards their social acceptance. Moreover, water conservation is framed as a consensual tool. It reassures that threats associated with water scarcity will be successfully managed to sustain urban growth in arid regions. In this sense, water conservation operates following a logic of fix, in line with the successive hydrosocial fixes that helped the development of arid lands and does not question inherited power structures in water management.  相似文献   

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11.
The paper discusses the impact of atmospheric circulation on the occurrence of various types of precipitation. A 146-year-long precipitation record from Kraków spanning the period 1863?C2008 was used alongside a calendar prepared by Nied?wied? (1981, 2009) describing circulation types covering the period 1873?C2008 and air masses and atmospheric fronts covering the period 1951?C2008 in southern Poland. The influence of atmospheric circulation on precipitation was measured using the frequency, conditional probability and average daily totals of precipitation. Circulation types, air masses and atmospheric fronts exerted influences on precipitation as a result of the seasonal variations of the thermal and moisture properties of air masses. The impact is best expressed by circulation types as these combine the aspect of cyclonicity/anticyclonicity with that of the direction of air advection, the two elements which determine the physical properties of the air. On average, liquid precipitation prevailed in all circulation types, except the Ea type in which snowfall dominated over liquid precipitation. Depending on the season, one of the three types of circulation, Wa, Wc and Bc, were shown to coincide with the greatest amount of liquid and thunderstorm precipitation. There was no single dominant circulation type for mixed precipitation or snowfall. In summer, the circulation types Nc, NEc, Cc and Bc were the most favourable to liquid and thunderstorm precipitation in terms of both probability and totals. In winter, snowfall was the most favoured by the Ec type. Frontal precipitation was twice as likely to occur as air mass precipitation, with the exception of snowfall which was predominantly an air mass type of precipitation in terms of probability, but its greatest totals were recorded on atmospheric fronts.  相似文献   

12.
归来(小品)     
人物田树槐男,70多岁,气象科学家文小娟女,15岁,中学生场景舞台正面幕布上是高楼大厦的群体建筑物,左侧是一块石碑,上写:艾望槐女士之墓田树槐(以下简称田,闷悠、迷惑、寻找他)找不到了,找不到了—…·艾小娟(以下简称文,活泼、天真地、热情地)老爷爷,你找什么?田:我找个地方1艾:啥地方?田:冉家村!艾:这儿就是冉家村啊!田;小朋友,你认错了,不是,不是1艾;没错。田:不对。艾:没错,没错1田:不对,不对!文:(生气地、不耐烦地)不对,不对?那你说说,在什么地方?田:南关外。艾:对呀,这是南关外!田:但…  相似文献   

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15.
梦(小小说)     
……我实实在在地醒了。出了身冷汗。妻和女儿睡得正香。清冷的月光泻进室内,朦朦胧胧地照在昨晚没有审完的风自记纸上。职业的习惯使我不能入睡,瞪着眼睛直到天色放亮。  相似文献   

16.
在地球表面进行的气象观测分为两类:感官观测,既不使用测量仪器而仅凭经验估计的观测;以及仪器观测,即借助于测量仪器并通常牵涉到对所得各实际读数进行定正和计算的观测  相似文献   

17.
真诚是友情的根基真诚是爱情的真谛真诚是信仰的灵魂真诚是事业的阶梯我们崇尚真诚把真诚的种子撒满大地我们赞美真诚育真诚的鲜花开通环宇真诚(诗)@马德明  相似文献   

18.
周秀骥 《气象》1977,3(7):12-13
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20.
随着 92 1 0工程中X .2 5线路的正常运行 ,原来NOVEIL工作站的大屏幕显示器即PHILIPS 5 1cm显示器的工作方式 (即通过 1块视频卡来做工作站的第 2显示器 )已不再适用。取而代之的是应该如何让它来做普通的显示器 ,不然势必会造成不必要的浪费。然而该显示器当初购进时并没有随之带来与普通显示卡连接的电缆 ,作者多方购买未成。如果想让其重新工作 ,只有通过自己制作才能完成。作者通过查找一些资料 ,终于成功地完成了这一任务。现将其制作过程介绍如下。1 制作配件视频电缆 1条 ,同轴电缆网线BNC接头 5个 ,显示卡 1 5…  相似文献   

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