This thesis attempts to investigate the humor in characterization in two novels,Sunshine Sketches of a Little Town by a Canadian writer Stephen Leacock and The Adventures ofHuckleberry Finn by an American writer Mark ...This thesis attempts to investigate the humor in characterization in two novels,Sunshine Sketches of a Little Town by a Canadian writer Stephen Leacock and The Adventures ofHuckleberry Finn by an American writer Mark Twain.Through comparison of characterization inthese two great works,the lively and funny appearances,psychological development and humorousconducts of the characters come to life.It does help readers have a thorough understanding of thehumor created by these two masters of realism in the worldwide literature.展开更多
The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigate...The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP.展开更多
Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise ...Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.展开更多
The greatest environmental disaster in Central Asiathe drying up of the Aral Seahas led to the formation of a new terrain, extending over 2.7 million hectares in Uzbekistan. This newly formed terrain is dynamically de...The greatest environmental disaster in Central Asiathe drying up of the Aral Seahas led to the formation of a new terrain, extending over 2.7 million hectares in Uzbekistan. This newly formed terrain is dynamically developing, with emerging soil formations replacing bottom sediments. This paper analyzes the results of a study on soil formation in the eastern part of the dried-up seabed, focusing on the influence of natural processes occurring there.展开更多
In order to study the relationship between temperature & sunshine and spring-sown wheat qua lity, a spring-sown experiment with 3 wheat varieties was conducted in Rikaze, Lasa, Linzhi, Beijing and Shenyang from 1...In order to study the relationship between temperature & sunshine and spring-sown wheat qua lity, a spring-sown experiment with 3 wheat varieties was conducted in Rikaze, Lasa, Linzhi, Beijing and Shenyang from 1998 to 2001. The results indicated that significant difference on some quality characteristics of experimental wheat varieties were observed from different locations and different years. The results also showed: protein content was positively correlated with wet gluten content, falling number, the average day temperature and sunshine hours from heading to maturation; and negatively correlated with the growing days and the average diurnal temperature difference from sowing to maturation; wet gluten content was positively correlated with the average day temperature and sunshine hours during the same period. Sedimentation value and falling number were positively correlated with the average sunshine hours from sowing to maturation. The basic way of wheat production in Tibet was as follows: mainly developing medium gluten wheat varieties, suitably planting weak gluten wheat varieties, introducing some inland excellent varieties.展开更多
The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good...The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good consistency in their characteristics. First, some kind of landform, such as stone pinnacles, rock well etc, kept the slippery rock surface. It was believed that they were resulted from the process in soil. Nearer the foot of rock the site was; more clear and integrated the form was. Second, the covered karst often associated with red weathering crust. Based on the character of the red weathering crust of the summit plane of Anduo Mountain, its forming environment was relatively humid and hot. Third, the best geomorphologic position, where the karst was bare, was not on the summit plane but on the slope.The baring degrees and later reworked characteristics of the covered karst made up of an integrated series. They could be divided into three kinds of districts according to their response to the Plateau uplift. (1) The western district, where the uplift was intensive, was mainly Tibet Plateau. For example, in Anduo Mountain, the covered karst was entirely denuded on the ground surface, and the rock surface was turned into mottled rock well because the frost weathering intensively reworked it. The red weathering crust was only kept in the bottom of rock, most of which was observed in the crack of limestone. The present karst process on the ground surface stopped. (2) The middle district, where the uplift degree was moderate, was mainly Yungui Plateau. The covered karst was partly denuded to form the stone pinnacles. Its part, which is baring, is changed to be aciculate and sharp\|pointed, and is active now. (3) The eastern district, where the uplift was weak, was mainly the northern part of Guangxi Province and the southern part of Hunan Province. The covered karst was entirely covered by soil and only observed in the section, which was excavated by human. The form of the covered karst generally had the typical character of the process below the soil.展开更多
This study is the first phase of research results from the student innovation project“Yunqiao Sunshine Health and Wellness Homestay”group at Chengdu Normal University.By analyzing the current state of the Sunshine H...This study is the first phase of research results from the student innovation project“Yunqiao Sunshine Health and Wellness Homestay”group at Chengdu Normal University.By analyzing the current state of the Sunshine Health and Wellness Tourism Area economy in the Panxi region of Sichuan,local policies,and the current state of Sunshine Health and Wellness homestays and hotels,this paper proposes the possibility of developing Sunshine Health and Wellness homestays and hotels through traditional Chinese medicine(TCM)health preservation methods.It also proposes development strategies for such hotels through a market survey SWOT analysis.展开更多
Based on the well-known modified Angstrom formula on the relationship between the sunshine duration and the global solar radiation, this paper aimed to estimate the value of the constant a and b in Cameroon. Only five...Based on the well-known modified Angstrom formula on the relationship between the sunshine duration and the global solar radiation, this paper aimed to estimate the value of the constant a and b in Cameroon. Only five cities (Maroua, Garoua, NGaoundéré, Yaoundé and Douala) had the both available in-situ data recorded during the period of eleven years (1996-2006) beside which four others cities (Dschang, Koundja, Yoko and Manfé) had only the in-situ sunshine duration available data recorded during the period of twenty years (1986-2006). The 9 cities were grouped in 3 different climate regions. Based on the data of the 5 first cities belonging the 3 regions, the follow constant values a1 = -0.05, a2 = -0.02, a3 = -0.14 and b1 = 0.94, b2 = 0.74, b3 = 1.12 were obtained. The Root Mean Square Error (RMSE) Mean Bias Error (MBE) and correlation coefficient (r) were also determined. Then we used these values to estimate the global solar radiation for the other four remain cities. The constants a and b obtained values are in accordance with those of the West Africa region which Cameroon belongs to. So they can be employed in estimating global solar radiation of location in Cameroon paying attention only to the geographical location information.展开更多
正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8...正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8个不同地表类型(包括高山荒漠,高山草地,(平原)城市和(平原)草地等)观测站点的地表辐射和能量通量数据.结果显示:(1)TP由于高原大气层稀薄且空气洁净,年平均入射短波辐射为251.3W m^(-2),是YRR的1.7倍.加之高原地表反照率高导致反射辐射(59.6 W m^(-2))是YRR的2.87倍.入射及出射的长波辐射为231.5和338.0 W m^(-2),分别为YRR的0.64和0.83.而两个区域的净辐射差异不大;(2)草地站更多的潜热释放使得地表总加热效率高于城市和高山荒漠,TP和YRR的草地站的年平均潜热分别为35.0和38.8 W m^(-2),而植被稀疏且土壤干燥的高山荒漠地区感热最大,年平均感热为42.1 W m^(-2);其次是城市下垫面,其年平均感热为37.7 W m^(-2).研究结果揭示了不同气候背景下典型下垫面地气相互作用特征,为地气相互作用过程深入分析奠定了基础.展开更多
[Objective] The change law and meteorological factor of sunshine duration in Dalian in recent 60 years were studied.[Method] Based on the statistical data of sunshine duration from base station in Dalian City from 195...[Objective] The change law and meteorological factor of sunshine duration in Dalian in recent 60 years were studied.[Method] Based on the statistical data of sunshine duration from base station in Dalian City from 1951 to 2009,the annual,seasonal,and monthly variation of sunshine duration in recent 60 years were analyzed,as well as its relationship with meteorological factors,and sunshine duration was detected by means of climate mutation theory.[Result] Annual sunshine duration in Dalian in recent 60 years showed decrease trend on the whole,and its climatic variation rate was-3.31 h/a,with larger annual variation,namely the difference between maximum value(1978) and minimum value(2003) reached 681 h;there was obvious seasonal variation in sunshine duration,with the order of autumn>summer>winter>spring,and their climatic variation rate were-1.18,-1.15,-0.91 and-0.62 h/a;except for March,sunshine duration in each month went down,especially October,while there was slight increase in March;sunshine percentage had inverse correlation relationship with total cloudiness,relative humidity and heavy fog days;annual sunshine duration reduced abruptly around 1983.[Conclusion] Our study could provide scientific foundation for the development of agriculture and forestry in Dalian City.展开更多
Based on the data of precipitation in Shenyang from 1951 to 2009,the variation characteristics of precipitation and sunshine hours in Shenyang in recent 59 years were analyzed and studied comprehensively from differen...Based on the data of precipitation in Shenyang from 1951 to 2009,the variation characteristics of precipitation and sunshine hours in Shenyang in recent 59 years were analyzed and studied comprehensively from different time scales of annual,seasonal and monthly,etc..And the relationship between the precipitation and sunshine duration was analyzed.It was concluded that the changes of precipitation between years is big,the distribution of the precipitation among four seasons is uneven,and the overall change trend of the precipitation is in downward from 1951 to 2009.It was also found that the sunshine duration changes are generally in decreased trend.展开更多
The surface albedo which is affected by the earth surface coverage or other surface characteristics is one of the important factors impacting remote sensing image information and therefore it can be calculated by inte...The surface albedo which is affected by the earth surface coverage or other surface characteristics is one of the important factors impacting remote sensing image information and therefore it can be calculated by integrating land coverage types with information of remote sensing images.Horqin sand land which was taken as an experimental area for study on Landsat-TM topography and atmospheric correction,then the Landsat-TM data inversion formula established by Liang was used to calculate the experimental zone albedo map;correlation analysis was performed to the surface albedo map and the land-use maps which was acquired by supervision and classification.The results revealed significant relations between land-use types and the surface albedo of study area.Additionally,the surface albedo and NDVI of the study area were statistically analyzed to obtain the study area's surface albedo and NDVI dependent equation.展开更多
The temporal and spatial changes of NDVI on the Tibetan Plateau, as well as the relationship between NDVI and precipitation, were discussed in this paper, by using 8-km resolution multi-temporal NOAA AVHRR-NDVI data f...The temporal and spatial changes of NDVI on the Tibetan Plateau, as well as the relationship between NDVI and precipitation, were discussed in this paper, by using 8-km resolution multi-temporal NOAA AVHRR-NDVI data from 1982 to 1999. Monthly maximum NDVI and monthly rainfall were used to analyze the seasonal changes, and annual maximum NDVI, annual effective precipitation and growing season precipitation (from April to August) were used to discuss the interannual changes. The dynamic change of NDVI and the corre- lation coefficients between NDVI and rainfall were computed for each pixel. The results are as follows: (1) The NDVI reached the peak in growing season (from July to September) on the Tibetan Plateau. In the northern and western parts of the plateau, the growing season was very short (about two or three months); but in the southern, vegetation grew almost all the year round. The correlation of monthly maximum NDVI and monthly rainfall varied in different areas. It was weak in the western, northern and southern parts, but strong in the central and eastern parts. (2) The spatial distribution of NDVI interannual dynamic change was different too. The increase areas were mainly distributed in southern Tibet montane shrub-steppe zone western part of western Sichuan-eastern Tibet montane coniferous forest zone, western part of northern slopes of Kunlun montane desert zone and southeastern part of southern slopes of Himalaya montane evergreen broad-leaved forest zone; the decrease areas were mainly distributed in the Qaidam montane desert zone, the western and northern parts of eastern Qinghai-Qilian montane steppe zone, southern Qinghai high cold meadow steppe zone and Ngari montane desert-steppe and desert zone. The spatial distribution of correlation coeffi- cient between annual effective rainfall and annual maximum NDVI was similar to the growing season rainfall and annual maximum NDVI, and there was good relationship between NDVI and rainfall in the meadow and grassland with medium vegetation cover, and the effect of rainfall on vegetation was small in the forest and desert area.展开更多
The summer snow anomalies over the Tibetan Plateau (TP) and their effects on climate variability are often overlooked,possibly due to the fact that some datasets cannot properly capture summer snow cover over high t...The summer snow anomalies over the Tibetan Plateau (TP) and their effects on climate variability are often overlooked,possibly due to the fact that some datasets cannot properly capture summer snow cover over high terrain.The satellite-derived Equal-Area Scalable Earth grid (EASE-grid) dataset shows that snow still exists in summer in the western part and along the southem flank of the TP.Analysis demonstrates that the summer snow cover area proportion (SCAP) over the TP has a significant positive correlation with simultaneous precipitation over the mei-yu-baiu (MB) region on the interannual time scale.The close relationship between the summer SCAP and summer precipitation over the MB region could not be simply considered as a simultaneous response to the Silk Road pattern and the SST anomalies in the tropical Indian Ocean and tropical central-eastern Pacific.The SCAP anomaly has an independent effect and may directly modulate the land surface heating and,consequently,vertical motion over the western TP,and concurrently induce anomalous vertical motion over the North Indian Ocean via a meridional vertical circulation.Through a zonal vertical circulation over the tropics and a Kelvin wave-type response,anomalous vertical motion over the North Indian Ocean may result in an anomalous high over the western North Pacific and modulate the convective activity in the western Pacific warm pool,which stimulates the East Asia-Pacific (EAP) pattern and eventually affects summer precipitation over the MB region.展开更多
Using the observed data from 184 stations over the Yunnan-Guizhou Plateau (YGP) from 1961 to 2005, the long-term trends in sunshine duration, cloud amount, dry visibility (Vd), dry extinction, and water vapor over...Using the observed data from 184 stations over the Yunnan-Guizhou Plateau (YGP) from 1961 to 2005, the long-term trends in sunshine duration, cloud amount, dry visibility (Vd), dry extinction, and water vapor over the YGP are analyzed. The results show that 85% of the stations recorded shortening annual sunshine duration, with the decrease rates between -12.2 and -173.7 h/10yr. Results of Mann-Kendall tests indicate that, among the stations with decreasing sunshine duration, 63.7% of them experienced an abrupt change that started in the 1970s and peaked in the 1980s. This decreasing trend has reversed in the early years of the 21st century. The cloud cover and water vapor content in the mid and lower levels over the YGP had no obvious changes during the study period. The annual averages of Vd declined from 34 km in the 1960s to 27 km at present. The annual mean dry extinction coefficient trended upward, from 0.176 to 0.190, on the YGP from 1980 to 2005. Analyses of cloud cover, water vapor, atmospheric visibility, and dry extinction coefficient revealed that emitted tropospheric aerosols (including air pollutants) resulting from increased energy consumption over the YGP could be a major Factor influencing the reductions of sunshine duration and atmospheric visibility.展开更多
Based on the 1961-1995 atmospheric apparent heat source/sink and the 1961-1990 snow-cover days and depth over the Qinghai-Xizang Plateau (QXP) and the 1961-1995 reanalysis data of NCEP/NCAR and the 1975-1994 OLR data,...Based on the 1961-1995 atmospheric apparent heat source/sink and the 1961-1990 snow-cover days and depth over the Qinghai-Xizang Plateau (QXP) and the 1961-1995 reanalysis data of NCEP/NCAR and the 1975-1994 OLR data, this paper discusses the interannual variability of the heat regime and its relation to atmospheric circulation It is shown that the interannual variability is pronounced, with maximal variability in spring and autumn, and the variability is heterogeneous horizontally. In the years with the weak (or strong) winter cold source, the deep trough over East Asia is to the east (or west) of its normal, which corresponds to strong (or weak) winter monsoon in East Asia. In the years with the strong (or weak) sum mer heat source, there exists an anomalous cyclone (or anticyclone) in the middle and lower troposphere over the QXP and ifs neighborhood and anomalous southwest (or northeast) winds over the Yangtze River valley of China, corresponding to strong (or weak) summer monsoon in East Asia. The summer heat source of the QXP is related to the intensity and position of the South Asia high. The QXP snow cover condition of April has a close relation to the heating intensity of summer. There is a remarkable negative correlation between the summer heat source of the QXP and the convection over the southeastern QXP, the Bay of Bengal, the Indo-China Peninsula, the southeastern Asia, the southwest part of China and the lower reaches of the Yangtze River and in the area from the Yellow Sea of China to the Sea of Japan.展开更多
Land surface temperature (LST), which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces (IS) spatial ...Land surface temperature (LST), which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces (IS) spatial patterns have on LST in Beijing, China. A classification and regression tree model (CART) was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper (TM) image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy (correlation coefficient of 0.94 and the average error of 8.59%). Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.展开更多
Based on the NOAA AVHRR-NDVI monthly data from 1981 to 2001, the spatial distribution and dynamic change of land cover along the Qinghai-Tibet Highway and Railway were studied. The results of the analytical data indic...Based on the NOAA AVHRR-NDVI monthly data from 1981 to 2001, the spatial distribution and dynamic change of land cover along the Qinghai-Tibet Highway and Railway were studied. The results of the analytical data indicate that the NDVI values in July, August and September are rather high during a year, and a linear trend by calculating NDVI of each pixel computed based on the average values of NDVI in July, August and September were obtained. The results are as follows: 1) Land cover of the study area by NDVI displays high at two sides of the area and low in the center, and agriculture area 〉 alpine meadow 〉 alpine grassland 〉 desert grassland. 2) In the study area, the amount ofpixels with high increase, slight increase, no change, slight decrease and high decrease account for 0.29%, 14.86%, 67.61%, 16.7% and 0.57% of the whole area, respectively. The increase of land cover pixels is mainly in the agriculture and alpine meadow and the decrease pixels mainly in the alpine grassland, desert grassland and hungriness. Grassland and hungriness contribute to the decrease mostly and artificial land and meadow contribute to the increase mostly. 3) In the area where human beings live, the changing trend is obvious, such as the valleys of Lhasa River and Huangshui River and area along the Yellow River; in the high altitude area with fewer people living, the changing trend is relatively low, like the area of Hoh Xil. 4) Human being's behaviors are a key factor followed by the climate changes affecting land cover.展开更多
The e?ect of anomalous snow cover over the Tibetan Plateau upon the South Asian summer monsoon is investigated by numerical simulations using the NCAR regional climate model (RegCM2) into which gravity wave ...The e?ect of anomalous snow cover over the Tibetan Plateau upon the South Asian summer monsoon is investigated by numerical simulations using the NCAR regional climate model (RegCM2) into which gravity wave drag has been introduced. The simulations adopt relatively realistic snow mass forcings based on Scanning Multi-channel Microwave Radiometer (SMMR) pentad snow depth data. The physical mechanism and spatial structure of the sensitivity of the South Asian early summer monsoon to snow cover anomaly over the Tibetan Plateau are revealed. The main results are summarized as follows. The heavier than normal snow cover over the Plateau can obviously reduce the shortwave radiation absorbed by surface through the albedo e?ect, which is compensated by weaker upward sensible heat ?ux associated with colder surface temperature, whereas the e?ects of snow melting and evaporation are relatively smaller. The anomalies of surface heat ?uxes can last until June and become unobvious in July. The decrease of the Plateau surface temperature caused by heavier snow cover reaches its maximum value from late April to early May. The atmospheric cooling in the mid-upper troposphere over the Plateau and its surrounding areas is most obvious in May and can keep a fairly strong intensity in June. In contrast, there is warming to the south of the Plateau in the mid-lower troposphere from April to June with a maximum value in May. The heavier snow cover over the Plateau can reduce the intensity of the South Asian summer monsoon and rainfall to some extent, but this in?uence is only obvious in early summer and almost disappears in later stages.展开更多
On the basis of snow data and AWS (Automatic Weather Station) data obtained from the Tibetan Plateau in recent years (1993 to 1999), the features of sensible heat, latent heat and net long-wave radiations are estimate...On the basis of snow data and AWS (Automatic Weather Station) data obtained from the Tibetan Plateau in recent years (1993 to 1999), the features of sensible heat, latent heat and net long-wave radiations are estimated, and their variations in more-snow year (1997/ 1998) and less-snow year (1996/ 1997) are analyzed comparatively. The relationships between snow cover of the Tibetan Plateau and plateau’s surface heating to the atmospheric heating are also discussed. The difference between more-snow and less-snow year in spring is remarkably larger than that in winter. Therefore, the effect of anomalous snow cover of the Tibetan Plateau in winter on the plateau heating appears more clearly in the following spring of anomalous snow cover. Key words Tibetan Plateau - Snow cover - Effects - Surface heat fluxes This research was supported by the National Key Programme for Developing Basic Sciences G1998040900 (I), National Natural Science Foundation of China (40075018) and Sichuan Youth Science and Technology Fund.展开更多
文摘This thesis attempts to investigate the humor in characterization in two novels,Sunshine Sketches of a Little Town by a Canadian writer Stephen Leacock and The Adventures ofHuckleberry Finn by an American writer Mark Twain.Through comparison of characterization inthese two great works,the lively and funny appearances,psychological development and humorousconducts of the characters come to life.It does help readers have a thorough understanding of thehumor created by these two masters of realism in the worldwide literature.
基金This research is funded by the National Natural Science Foundation of China(Grant No.42075050)Fundamental Research Funds for the Central Universities(Grant No.K20220232).
文摘The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP.
文摘Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.
文摘The greatest environmental disaster in Central Asiathe drying up of the Aral Seahas led to the formation of a new terrain, extending over 2.7 million hectares in Uzbekistan. This newly formed terrain is dynamically developing, with emerging soil formations replacing bottom sediments. This paper analyzes the results of a study on soil formation in the eastern part of the dried-up seabed, focusing on the influence of natural processes occurring there.
基金This experiment was funded by the National Natural Science Foundation of China(39760039)We thank China National Bureau of Meteorology supplying relevant meteorological data.
文摘In order to study the relationship between temperature & sunshine and spring-sown wheat qua lity, a spring-sown experiment with 3 wheat varieties was conducted in Rikaze, Lasa, Linzhi, Beijing and Shenyang from 1998 to 2001. The results indicated that significant difference on some quality characteristics of experimental wheat varieties were observed from different locations and different years. The results also showed: protein content was positively correlated with wet gluten content, falling number, the average day temperature and sunshine hours from heading to maturation; and negatively correlated with the growing days and the average diurnal temperature difference from sowing to maturation; wet gluten content was positively correlated with the average day temperature and sunshine hours during the same period. Sedimentation value and falling number were positively correlated with the average sunshine hours from sowing to maturation. The basic way of wheat production in Tibet was as follows: mainly developing medium gluten wheat varieties, suitably planting weak gluten wheat varieties, introducing some inland excellent varieties.
文摘The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good consistency in their characteristics. First, some kind of landform, such as stone pinnacles, rock well etc, kept the slippery rock surface. It was believed that they were resulted from the process in soil. Nearer the foot of rock the site was; more clear and integrated the form was. Second, the covered karst often associated with red weathering crust. Based on the character of the red weathering crust of the summit plane of Anduo Mountain, its forming environment was relatively humid and hot. Third, the best geomorphologic position, where the karst was bare, was not on the summit plane but on the slope.The baring degrees and later reworked characteristics of the covered karst made up of an integrated series. They could be divided into three kinds of districts according to their response to the Plateau uplift. (1) The western district, where the uplift was intensive, was mainly Tibet Plateau. For example, in Anduo Mountain, the covered karst was entirely denuded on the ground surface, and the rock surface was turned into mottled rock well because the frost weathering intensively reworked it. The red weathering crust was only kept in the bottom of rock, most of which was observed in the crack of limestone. The present karst process on the ground surface stopped. (2) The middle district, where the uplift degree was moderate, was mainly Yungui Plateau. The covered karst was partly denuded to form the stone pinnacles. Its part, which is baring, is changed to be aciculate and sharp\|pointed, and is active now. (3) The eastern district, where the uplift was weak, was mainly the northern part of Guangxi Province and the southern part of Hunan Province. The covered karst was entirely covered by soil and only observed in the section, which was excavated by human. The form of the covered karst generally had the typical character of the process below the soil.
文摘This study is the first phase of research results from the student innovation project“Yunqiao Sunshine Health and Wellness Homestay”group at Chengdu Normal University.By analyzing the current state of the Sunshine Health and Wellness Tourism Area economy in the Panxi region of Sichuan,local policies,and the current state of Sunshine Health and Wellness homestays and hotels,this paper proposes the possibility of developing Sunshine Health and Wellness homestays and hotels through traditional Chinese medicine(TCM)health preservation methods.It also proposes development strategies for such hotels through a market survey SWOT analysis.
文摘Based on the well-known modified Angstrom formula on the relationship between the sunshine duration and the global solar radiation, this paper aimed to estimate the value of the constant a and b in Cameroon. Only five cities (Maroua, Garoua, NGaoundéré, Yaoundé and Douala) had the both available in-situ data recorded during the period of eleven years (1996-2006) beside which four others cities (Dschang, Koundja, Yoko and Manfé) had only the in-situ sunshine duration available data recorded during the period of twenty years (1986-2006). The 9 cities were grouped in 3 different climate regions. Based on the data of the 5 first cities belonging the 3 regions, the follow constant values a1 = -0.05, a2 = -0.02, a3 = -0.14 and b1 = 0.94, b2 = 0.74, b3 = 1.12 were obtained. The Root Mean Square Error (RMSE) Mean Bias Error (MBE) and correlation coefficient (r) were also determined. Then we used these values to estimate the global solar radiation for the other four remain cities. The constants a and b obtained values are in accordance with those of the West Africa region which Cameroon belongs to. So they can be employed in estimating global solar radiation of location in Cameroon paying attention only to the geographical location information.
基金supported by the National Natural Science Foundation of China,under the project entitled“The study of land-atmosphere water and heat flux interaction over the complex terrain of the north and south slopes of the Qomolangma region"[grant number 42230610]a Ministry of Science and Technology of China project called“Landatmosphere interaction and its climate effect of the Second Tibetan Plateau Scientific Expedition and Research Program"[grant number 2019QzKK0103]the Youth Innovation Promotion Association of the Chinese Academy of Sciences[2022069].
文摘正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8个不同地表类型(包括高山荒漠,高山草地,(平原)城市和(平原)草地等)观测站点的地表辐射和能量通量数据.结果显示:(1)TP由于高原大气层稀薄且空气洁净,年平均入射短波辐射为251.3W m^(-2),是YRR的1.7倍.加之高原地表反照率高导致反射辐射(59.6 W m^(-2))是YRR的2.87倍.入射及出射的长波辐射为231.5和338.0 W m^(-2),分别为YRR的0.64和0.83.而两个区域的净辐射差异不大;(2)草地站更多的潜热释放使得地表总加热效率高于城市和高山荒漠,TP和YRR的草地站的年平均潜热分别为35.0和38.8 W m^(-2),而植被稀疏且土壤干燥的高山荒漠地区感热最大,年平均感热为42.1 W m^(-2);其次是城市下垫面,其年平均感热为37.7 W m^(-2).研究结果揭示了不同气候背景下典型下垫面地气相互作用特征,为地气相互作用过程深入分析奠定了基础.
基金Supported by National Natural Science Foundation of China (40971294)Science and Technology Planning Project of Dalian Science and Technology Bureau(2009E11SF230)~~
文摘[Objective] The change law and meteorological factor of sunshine duration in Dalian in recent 60 years were studied.[Method] Based on the statistical data of sunshine duration from base station in Dalian City from 1951 to 2009,the annual,seasonal,and monthly variation of sunshine duration in recent 60 years were analyzed,as well as its relationship with meteorological factors,and sunshine duration was detected by means of climate mutation theory.[Result] Annual sunshine duration in Dalian in recent 60 years showed decrease trend on the whole,and its climatic variation rate was-3.31 h/a,with larger annual variation,namely the difference between maximum value(1978) and minimum value(2003) reached 681 h;there was obvious seasonal variation in sunshine duration,with the order of autumn>summer>winter>spring,and their climatic variation rate were-1.18,-1.15,-0.91 and-0.62 h/a;except for March,sunshine duration in each month went down,especially October,while there was slight increase in March;sunshine percentage had inverse correlation relationship with total cloudiness,relative humidity and heavy fog days;annual sunshine duration reduced abruptly around 1983.[Conclusion] Our study could provide scientific foundation for the development of agriculture and forestry in Dalian City.
文摘Based on the data of precipitation in Shenyang from 1951 to 2009,the variation characteristics of precipitation and sunshine hours in Shenyang in recent 59 years were analyzed and studied comprehensively from different time scales of annual,seasonal and monthly,etc..And the relationship between the precipitation and sunshine duration was analyzed.It was concluded that the changes of precipitation between years is big,the distribution of the precipitation among four seasons is uneven,and the overall change trend of the precipitation is in downward from 1951 to 2009.It was also found that the sunshine duration changes are generally in decreased trend.
基金Supported by Institute of Atmospheric Environment CMA,Shenyang
文摘The surface albedo which is affected by the earth surface coverage or other surface characteristics is one of the important factors impacting remote sensing image information and therefore it can be calculated by integrating land coverage types with information of remote sensing images.Horqin sand land which was taken as an experimental area for study on Landsat-TM topography and atmospheric correction,then the Landsat-TM data inversion formula established by Liang was used to calculate the experimental zone albedo map;correlation analysis was performed to the surface albedo map and the land-use maps which was acquired by supervision and classification.The results revealed significant relations between land-use types and the surface albedo of study area.Additionally,the surface albedo and NDVI of the study area were statistically analyzed to obtain the study area's surface albedo and NDVI dependent equation.
基金National Basic Research Program of China, No.2005CB422006 National Natural Science Foundation o China, No.40331006 No.90202012
文摘The temporal and spatial changes of NDVI on the Tibetan Plateau, as well as the relationship between NDVI and precipitation, were discussed in this paper, by using 8-km resolution multi-temporal NOAA AVHRR-NDVI data from 1982 to 1999. Monthly maximum NDVI and monthly rainfall were used to analyze the seasonal changes, and annual maximum NDVI, annual effective precipitation and growing season precipitation (from April to August) were used to discuss the interannual changes. The dynamic change of NDVI and the corre- lation coefficients between NDVI and rainfall were computed for each pixel. The results are as follows: (1) The NDVI reached the peak in growing season (from July to September) on the Tibetan Plateau. In the northern and western parts of the plateau, the growing season was very short (about two or three months); but in the southern, vegetation grew almost all the year round. The correlation of monthly maximum NDVI and monthly rainfall varied in different areas. It was weak in the western, northern and southern parts, but strong in the central and eastern parts. (2) The spatial distribution of NDVI interannual dynamic change was different too. The increase areas were mainly distributed in southern Tibet montane shrub-steppe zone western part of western Sichuan-eastern Tibet montane coniferous forest zone, western part of northern slopes of Kunlun montane desert zone and southeastern part of southern slopes of Himalaya montane evergreen broad-leaved forest zone; the decrease areas were mainly distributed in the Qaidam montane desert zone, the western and northern parts of eastern Qinghai-Qilian montane steppe zone, southern Qinghai high cold meadow steppe zone and Ngari montane desert-steppe and desert zone. The spatial distribution of correlation coeffi- cient between annual effective rainfall and annual maximum NDVI was similar to the growing season rainfall and annual maximum NDVI, and there was good relationship between NDVI and rainfall in the meadow and grassland with medium vegetation cover, and the effect of rainfall on vegetation was small in the forest and desert area.
基金the support of the National Natural Science Foundation of China (Grant No. 41271434)the National Key Technologies R&D Program in the 12th Five Year Plan of China (Grant No. 2012BAH32B03)+6 种基金the Hong Kong GRF (Grant No. CUHK 457212)the ITF (Grant No. GHP/002/11GD)the support of the Hong Kong Research Grants Council (Grant No. CUHK 403612)the National Natural Science Foundation of China (Grant Nos. 41275081 and 41228006)the support of the National Natural Science Foundation of China (Grant Nos. 41375090 and 41221064)the Special Project of the National International Science and Technology Cooperation of China (Grant No. 2011DFG23450)the Basic Research Fund of CAMS (Grant No. 2013Z002)
文摘The summer snow anomalies over the Tibetan Plateau (TP) and their effects on climate variability are often overlooked,possibly due to the fact that some datasets cannot properly capture summer snow cover over high terrain.The satellite-derived Equal-Area Scalable Earth grid (EASE-grid) dataset shows that snow still exists in summer in the western part and along the southem flank of the TP.Analysis demonstrates that the summer snow cover area proportion (SCAP) over the TP has a significant positive correlation with simultaneous precipitation over the mei-yu-baiu (MB) region on the interannual time scale.The close relationship between the summer SCAP and summer precipitation over the MB region could not be simply considered as a simultaneous response to the Silk Road pattern and the SST anomalies in the tropical Indian Ocean and tropical central-eastern Pacific.The SCAP anomaly has an independent effect and may directly modulate the land surface heating and,consequently,vertical motion over the western TP,and concurrently induce anomalous vertical motion over the North Indian Ocean via a meridional vertical circulation.Through a zonal vertical circulation over the tropics and a Kelvin wave-type response,anomalous vertical motion over the North Indian Ocean may result in an anomalous high over the western North Pacific and modulate the convective activity in the western Pacific warm pool,which stimulates the East Asia-Pacific (EAP) pattern and eventually affects summer precipitation over the MB region.
基金funded by the National Natural Science Foundation of China (NSFC) (Grant No. 40965009)the Guizhou Provincial Meteorological Bureau Key Laboratory Programme (No. KF200906)
文摘Using the observed data from 184 stations over the Yunnan-Guizhou Plateau (YGP) from 1961 to 2005, the long-term trends in sunshine duration, cloud amount, dry visibility (Vd), dry extinction, and water vapor over the YGP are analyzed. The results show that 85% of the stations recorded shortening annual sunshine duration, with the decrease rates between -12.2 and -173.7 h/10yr. Results of Mann-Kendall tests indicate that, among the stations with decreasing sunshine duration, 63.7% of them experienced an abrupt change that started in the 1970s and peaked in the 1980s. This decreasing trend has reversed in the early years of the 21st century. The cloud cover and water vapor content in the mid and lower levels over the YGP had no obvious changes during the study period. The annual averages of Vd declined from 34 km in the 1960s to 27 km at present. The annual mean dry extinction coefficient trended upward, from 0.176 to 0.190, on the YGP from 1980 to 2005. Analyses of cloud cover, water vapor, atmospheric visibility, and dry extinction coefficient revealed that emitted tropospheric aerosols (including air pollutants) resulting from increased energy consumption over the YGP could be a major Factor influencing the reductions of sunshine duration and atmospheric visibility.
基金the auspices of the National!(G1998040800)CAS's Key Project for Basic Research on the Tibetan Plateau! (KZ951-A1-204, KZ95T-
文摘Based on the 1961-1995 atmospheric apparent heat source/sink and the 1961-1990 snow-cover days and depth over the Qinghai-Xizang Plateau (QXP) and the 1961-1995 reanalysis data of NCEP/NCAR and the 1975-1994 OLR data, this paper discusses the interannual variability of the heat regime and its relation to atmospheric circulation It is shown that the interannual variability is pronounced, with maximal variability in spring and autumn, and the variability is heterogeneous horizontally. In the years with the weak (or strong) winter cold source, the deep trough over East Asia is to the east (or west) of its normal, which corresponds to strong (or weak) winter monsoon in East Asia. In the years with the strong (or weak) sum mer heat source, there exists an anomalous cyclone (or anticyclone) in the middle and lower troposphere over the QXP and ifs neighborhood and anomalous southwest (or northeast) winds over the Yangtze River valley of China, corresponding to strong (or weak) summer monsoon in East Asia. The summer heat source of the QXP is related to the intensity and position of the South Asia high. The QXP snow cover condition of April has a close relation to the heating intensity of summer. There is a remarkable negative correlation between the summer heat source of the QXP and the convection over the southeastern QXP, the Bay of Bengal, the Indo-China Peninsula, the southeastern Asia, the southwest part of China and the lower reaches of the Yangtze River and in the area from the Yellow Sea of China to the Sea of Japan.
基金Project supported by the Pilot Project of Knowledge Innovadon Program of Chinese Academy of Sciences (No. KZCX32SW2424).
文摘Land surface temperature (LST), which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces (IS) spatial patterns have on LST in Beijing, China. A classification and regression tree model (CART) was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper (TM) image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy (correlation coefficient of 0.94 and the average error of 8.59%). Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.
基金National Natural Science Foundation of China No.90202012+1 种基金 National Basic Research Program of China, No.2005CB422006 No. 2002CB412507
文摘Based on the NOAA AVHRR-NDVI monthly data from 1981 to 2001, the spatial distribution and dynamic change of land cover along the Qinghai-Tibet Highway and Railway were studied. The results of the analytical data indicate that the NDVI values in July, August and September are rather high during a year, and a linear trend by calculating NDVI of each pixel computed based on the average values of NDVI in July, August and September were obtained. The results are as follows: 1) Land cover of the study area by NDVI displays high at two sides of the area and low in the center, and agriculture area 〉 alpine meadow 〉 alpine grassland 〉 desert grassland. 2) In the study area, the amount ofpixels with high increase, slight increase, no change, slight decrease and high decrease account for 0.29%, 14.86%, 67.61%, 16.7% and 0.57% of the whole area, respectively. The increase of land cover pixels is mainly in the agriculture and alpine meadow and the decrease pixels mainly in the alpine grassland, desert grassland and hungriness. Grassland and hungriness contribute to the decrease mostly and artificial land and meadow contribute to the increase mostly. 3) In the area where human beings live, the changing trend is obvious, such as the valleys of Lhasa River and Huangshui River and area along the Yellow River; in the high altitude area with fewer people living, the changing trend is relatively low, like the area of Hoh Xil. 4) Human being's behaviors are a key factor followed by the climate changes affecting land cover.
基金the National Natural Science foundation of China(Grant No.40375027) opening item of the Key Laboratory for Mleteorological Disasters and Environmental Change of Nanjing Institute of Mleteorology(No.K2107).
文摘The e?ect of anomalous snow cover over the Tibetan Plateau upon the South Asian summer monsoon is investigated by numerical simulations using the NCAR regional climate model (RegCM2) into which gravity wave drag has been introduced. The simulations adopt relatively realistic snow mass forcings based on Scanning Multi-channel Microwave Radiometer (SMMR) pentad snow depth data. The physical mechanism and spatial structure of the sensitivity of the South Asian early summer monsoon to snow cover anomaly over the Tibetan Plateau are revealed. The main results are summarized as follows. The heavier than normal snow cover over the Plateau can obviously reduce the shortwave radiation absorbed by surface through the albedo e?ect, which is compensated by weaker upward sensible heat ?ux associated with colder surface temperature, whereas the e?ects of snow melting and evaporation are relatively smaller. The anomalies of surface heat ?uxes can last until June and become unobvious in July. The decrease of the Plateau surface temperature caused by heavier snow cover reaches its maximum value from late April to early May. The atmospheric cooling in the mid-upper troposphere over the Plateau and its surrounding areas is most obvious in May and can keep a fairly strong intensity in June. In contrast, there is warming to the south of the Plateau in the mid-lower troposphere from April to June with a maximum value in May. The heavier snow cover over the Plateau can reduce the intensity of the South Asian summer monsoon and rainfall to some extent, but this in?uence is only obvious in early summer and almost disappears in later stages.
基金the National Key Programme for Developing Basic SciencesG1998040900 (I)National Natural Science Foundation of China (400750
文摘On the basis of snow data and AWS (Automatic Weather Station) data obtained from the Tibetan Plateau in recent years (1993 to 1999), the features of sensible heat, latent heat and net long-wave radiations are estimated, and their variations in more-snow year (1997/ 1998) and less-snow year (1996/ 1997) are analyzed comparatively. The relationships between snow cover of the Tibetan Plateau and plateau’s surface heating to the atmospheric heating are also discussed. The difference between more-snow and less-snow year in spring is remarkably larger than that in winter. Therefore, the effect of anomalous snow cover of the Tibetan Plateau in winter on the plateau heating appears more clearly in the following spring of anomalous snow cover. Key words Tibetan Plateau - Snow cover - Effects - Surface heat fluxes This research was supported by the National Key Programme for Developing Basic Sciences G1998040900 (I), National Natural Science Foundation of China (40075018) and Sichuan Youth Science and Technology Fund.