Analysis of Climate Characteristics and Advantages of Climate Resources in Zhangjiakou Region

By analyzing the climate characteristics of Zhangjiakou region,the advantages in its climate resources are explored.Analysis shows that abundant solar energy resources are the fundamental condition for promoting photovoltaic power generation projects and have become an important lever for poverty alleviation work;wind energy is one of the main climate resources in Zhangjiakou City,providing important conditions for the development of wind power generation industry;the Bashang region has a long duration of cold weather and long freezing time,which has not only the inherent climate advantage of conducting ice sports,but also the advantage of natural cold storage;the Bashang region has a long snowfall time,relatively more snowfall days,and a long snow accumulation time,which has a unique climate advantage for developing tourism culture with ice and snow sports as the theme;the climate characteristics of cold winter and cool summer,with natural cooling mechanism,are superior conditions for the development of large-scale modern data information industry.

Study on Fog Climate Characteristic and Forecasting Method in East of Hexi Corridor

Using fog meteorological data of five stations of Wuwei in east of Hexi Corridor from 1961 to 2008,geography distribution and climate characteristic of fog were analyzed with statistical method.The results showed that fog had the obvious region characteristic,fog days were more in mountainous area than Sichuan area and were more in south than north.Fog assumed reducing tendency year by year.Fog occurring frequency was the highest from July to October in one year.Fog occurring centralized time was form 20:00 to next day 08:00 in one day.Selecting of ECMWF numerical forecast grid field,factor was initially elected with Press criterion,factor was selected with stepwise regression forecast method.The fog forecasting equation was built with optimal subset regression.The overall situation and the most superior significance equations of fog forecasting were ascertained finally for spring,summer and autumn.Fitting rate three seasonal forecasting equation were 85.5%,82.1% and 81.2% respectively,which would provide objective and effective instruction products for forecasting service.

Wavelet analysis of spring climate characteristics in arid aeolian area of agro-pastoral ecotone in China

The unique regional climate characteristics are among the main reasons for the frequent wind-sand activity in arid and cold areas in the agro-pastoral ecotone in Inner Mongolia, China. This paper focuses on the time series of temperature and precipitation in spring when sandstorms often occur in the area. Based on meteorological data for a 46-year period from 1959 to 2004, multi-scale variations and abrupt changes in temperature and precipitation were analyzed with the Mexican hat function （MHF） wavelet method, showing the multi-scale variation characteristics of temperature and precipitation, as well as the periods and change points at different time scales. The relationship between temperature and precipitation was obtained using the wavelet analysis method. Obvious staggered features of the variations of spring temperature and precipitation were observed in this agro-pastoral ecotone. The strongest oscillation periods of spring temperature variations were 1 and 22 years, while for precipitation, the strongest oscillation periods of variations were 2, 8, and 22 years. In addition, lower spring temperature corresponded to lower precipitation, whereas higher temperature yielded higher precipitation rate.

Climate Characteristics of the Formation of Dense Fog during Autumn and Winter in Shandong Inland

We use historical materials of monthly foggy days from 84 stations of Shandong Province during the latest decades,analyze the spatial distribution features of mean foggy days during autumn and winter and annual mean foggy days in Shandong.Result shows that foggy weather have strong regional characteristics,there are obvious difference between Shandong inland and coast in terms of the frequency of foggy days,winter and autumn are the peak period of dense fog in the inland of Shandong,however,dense fog is less in coastal area.Take Jinan for example,we have emphatically analyzed the activity change rules of foggy days during autumn and winter since 1952 in the inland,as well as the characteristics of atmospheric circulation during the frequently-occurring year and less frequently-occurring year of dense fog.

Short-term Climate Characteristics at Ny-lesund over the Arctic Tundra Area

Based on the Germany Koldwey Station＇s 1994-2003 conventional observation hourly data, this paper conducts a statistical analysis on the short-term climate characteristics for an arctic tundra region （Ny-Alesund island） where our first arctic expedition station （Huanghe Station） was located. Affected by the North Atlantic warming current, this area has a humid temperate climate, and the air temperature at Ny-Alesund rose above 0 ℃ even during deep winter season during our research period. The wind speed in this area was low and appeared most at southeast direction. We find that the temperature at Ny-Alesund rose in the faster rate （0.68℃/10 a） than those at the whole Arctic area. Compared with the floating ices where our expedition conducted in the Arctic, Ny-Alesund was warmer and more humid and had lower wind speed. Comparison Of the near surface air temperature derived by NCEP/NCAR reanalysis to the conventional measurements conducted at the Koldwey site in Ny-Alesund area shows a good agreement for winter season and a slgnificant difference for summer season.

Analysis on the Climate Characteristics of Rainstorm Weather over Huaihe River Basin and Its Influence on Agriculture Production

By the daily precipitation data at 18 meteorological stations of Huaihe River basin in recent 50 years,the temporal-spatial distribution features of the rainstorm over Huaihe River basin during 1958- 2007 and its influence on agriculture production were analyzed. The results showed that the interannual change magnitudes of the rainstorm days and rainstorm amount from 1958 to 2007 were fierce. Especially in the late 1990 s,rainstorm days and rainstorm amount increased obviously. As a result of interannual variability of East Asian summer monsoon and East Asian circulation system,rainstorm had significant quasi-2-year periodic oscillation in summer. Because of water vapor and terrain,rainstorm mainly concentrated in the southwest over the Huaihe River basin,but was less in the north.

Analyses on Climate Characteristics in Xingtai City during 1954 - 2010

[Objective] The research aimed to analyze climate characteristics in Xingtai City during 1954-2010.[Method] Based on climate data in Xingtai City during 1954-2010,by using line chart,trend chart,climatic variability and statistical diagram,the climate characteristics in Xingtai City in 57 years were analyzed.[Result] The annual average temperature,annual average maximum and minimum temperatures in Xingtai City during 1954-2010 all presented gradual rise trend.The rise velocity of annual average maximum temperature was the slowest.The annual average temperature presented rise trend year by year.The rise velocity of annual average minimum temperature was the fastest.The annual average rainfall,wind speed,relative humidity and sunshine hours all presented gradual decline trend,while the annual average total cloud amount presented increase trend.The annual average ground temperatures at 0,5,10,15 and 20 cm in Xingtai City during 1954-2010 were respectively 15.6,15.7,15.8,15.8 and 15.8 ℃.The annual average ground temperatures at 40 and 80 cm,1.6 and 3.2 m in Xingtai City during 1981-2010 were respectively 15.2,15.2,15.4 and 15.4 ℃.It was clear that the ground temperature at deep layer gradually rose as depth increase.[Conclusion] The research provided theoretical basis for guiding agricultural production in Xingtai City.

The Climate Characteristics of Heavy Rainfall in China from 1951 to 2000

This paper analyzed the temporal and spatial distribution of heavy rainfall in China from 1951 to 2000.The results showed that since 1980s,the occurrence frequency of rainfall and major storm disasters increased significantly in Sichuan Province.In 1990s,Hebei heavy rainfall frequency and major storm disasters had increased remarkably.Heavy rainfall occurred mainly from May to August.The heavy storm largely took place from April to September.Catastrophic rains occurred in October in 1990s.Liaoning and Hubei Provinces had undergone the most amounts of heavy storms in 1950s.Jiangxi Province had undergone the most amounts in 1960s and Shandong in 1970s,Sichuan in 1980s and Hebei in 1990s.

Climate Characteristics of Hail-falling in Zhangjiajie and Comparative Analysis of Multiple Cases of Hail in 2005

Based on the hail-falling data in Zhangjiajie during 1901-2000,the climate characteristics (the occurrence times of hail,the spatial and temporal distribution,the path of hail) and the circulation situation,stability,feature layer of hail cases in 2005 were compared and analyzed.And some indicators related to hail forecast in Zhangjiajie were found.The research aimed to improve the level of hail forecast,provide operational information for hail suppression,and guide the disaster prevention and alleviation.

Characteristics of Dry and Wet Climate in Shandong Province Based on Standardized Precipitation Index

Based on the monthly precipitation data of 116 meteorological stations in Shandong Province during 1970-2021,standardized precipitation index(SPI)was calculated,and the methods of linear fitting,mutation test and Morlet wavelet analysis were used to analyze the change trend and temporal and spatial distribution characteristics of SPI index in the past 52 years.The results show that there were more normal years in Shandong Province,and the frequency reached 38.46%.There was severe drought in the 1980s and more wet years after 2003.SPI index showed an upward trend in spring,summer and winter but a weak arid trend in autumn.In addition,intense dry weather was more frequent in summer.Spatially,the climate was normal or humid in most areas of Shandong Province.The regions with more wet years were located in the central and northeast Shandong and the peninsula,while the climate was normal in the southwest and north of Shandong.The areas with more dry years were mainly located in the northwest of Shandong Province.There was mainly local and global drought in Shandong Province,and the arid area showed a decreasing trend.In the past 52 years,Shandong Province experienced quasi-4 times of alternation between dry and wet climate.The long period of 21 a was the first main period,and the climate would be still wet in Shandong Province in the future.In terms of mutation,the climate in Shandong Province became humid after 2003,and 2003 was the mutation point.After the abrupt change,the climate changed from gradually drying to wetting.

Analysis on the Hail Climate and Radar Characteristics in Linyi City

[Objective] The research aimed to study the hail climate and radar characteristics in Linyi City.[Method] The five representative stations which were Mengyin,Yishui,Linshu,Cangshan,Linyi and were collectively called as Linyi City in Yimeng mountain area were selected.From the hail path,weather situation and influence system,the 40 times hail weather processes which happened in every station in June during 1965-2008 were carried out the statistics analysis.The typical weather situation and physical structure characteristics in the hail weather process in Linyi City were studied.On this basis,the statistical analysis on the new generation weather radar characteristics in the hail process during 2003-2008 was carried out.The climatic index of hail occurrence,the characteristic index of radar data and the radar observation characteristic in the city were discussed.[Result] The weather systems which affected the hail shooting in Linyi City were Mongolia cold vortex type,eastward shift small trough type,northwest airflow cold temperature trough type and so on.On the 6 h ground chart before the hail shooting,there were the small low pressure,cold front or wind shear line(airflow convergence field) in Shandong Province.They had the 'trigger' and 'development' effects on the occurrence and development of strong convection hail shooting.The joining of small trough in the rear of 500 hPa low vortex had three forms that were the west small trough supplementary type,the airflow field divergence in front of vortex and the small trough in the rear of vortex southward swing in general.When the vertical liquid water content quickly increased from zero or the small amount to above 40 kg/m2,it was possible to generate the hail weather.In the different months,when the echo intensity of convective cloud body >50 dBz,the initial echo height >5 km,and the crown elevation,strong center height reached the certain values,it was possible to generate the hail weather.On the radar radial velocity chart,the meso-scale convective system characteristic(the bottom layer was the convergence,and the high layer was the divergence) was obvious.At 1.5° and 3.4° elevation angles in the middle layer,there was the strong wind shear in the vertical direction of convective storm monomer.[Conclusion] The research provided the certain reference value for the analysis and forecast of this kind of weather.

Experimental study on the effects of climatic characteristics on people's adaptability to thermal environment

In order to find out how the climatic characteristics affect people＇s adaptability to thermal environments,experimental studies in a climate chamber are conducted on the effects of transition seasons（from spring to summer）and the occupants＇ native areas on indoor thermal sensations.Results reveal that people＇s tolerances to cool and warm indoor environments are different in the transition season.When the outdoor temperature is higher,the occupants have a weaker tolerance to a cool indoor environment,but a stronger tolerance to a warm indoor environment.Besides,it is found that the occupants＇ thermal sensations depend on both the climatic characteristics of the season and their native areas.The people from southern China present a greater tolerance to both warm and cool indoor environments than those from northern China.The reason can be explained according to the occupants＇ adaptability to the climatic characteristics and the indoor thermal environments of their native areas in different climate zones.

Characteristics Analysis and the Early-warning Service System of Heavy Fog in Chizhou City

By analyzing the heavy fog data in Chizhou City in recent 50 years(1959-2007),the general rules of meteorological elements variations were found when the heavy fog happened.The meteorological elements included the temperature,humidity,wind direction,wind speed,air pressure and so on.The conceptual models of high-altitude and ground situation were established when the heavy fog happened in Chizhou City.Based on considering sufficiently the special geographical environment in Chizhou City,we found the key factors which affected the local heavy fog via the relative analyses.By using the statistical forecast methods which included the second-level judgment method and regression method of event probability and so on,the forecast mode equation of heavy fog was established.Moreover,the objective forecast system of heavy fog in Chizhou City was also manufactured.It provided the basis and platform which could be referred for the heavy fog forecast,service and the release of early-warning signal.

Climatic Characteristics Analysis of Flood-producing Rainstorm in Duhe River Basin

Based on the data from 1998 to 2005,area rainfall,flow of main hydrologic stations in Duhe River and upstream water level of the dam of Huanglongtan Reservoir in the lower reaches of Duhe River were analyzed,and the standard of flood-producing rainstorm in Duhe River was given,while temporal and spatial distribution and circulation flow situation characteristic of flood-producing rainstorm in Duhe River were studied.The results showed that the flood-producing rainstorm in Duhe River was mainly continuous intensive precipitation with the characteristic of long duration.There was most rainfall in Zhuxiquan River,Zhushanguandu River and southwest part of the middle and upper reaches of Duhe River,and next came Zhuxi River.Flood-producing rainstorm occurred in Duhe River with some favorable circulation features.For example,it was more favorable in the west Pacific subtropical high,and the convergence zone at northeast-southwest direction was formed between subtropical high and continental high pressure at 700 hPa,while southwest vortex moved eastward.Low pressure system at 850 hPa in south part of plateau developed and moved eastward to Chongqing region and formed low vortex or shear near Duhe River basin.Moreover,the characteristics of physical quantity field were analyzed,the results showed that temperature in plateau area and the south area of Duhe River basin increased obviously before rainstorm,and east pathway was the main path of cold air which affected flood-producing rainstorm in Duhe River.There was a θse intensive belt with NEE-SWW direction at 30°-40° N at 925-500 hPa,and moisture convergence was beneficial to the occurrence of rainstorm in Duhe River.

Climatology Characteristics of Walker Circulation in East-west Direction in the Equatorial Tropical Pacific Ocean

By using OLR monthly average data which was observed by American NOAA satellite and 500 hPa ω monthly average data of NCEP reanalysis,the indexes which represented the equatorial longitudinal circulation characteristics were defined. According to the intensity,scope and distribution characteristics of longitudinal circulation in the tropical equator area,the indexes which represented the intensity,position and scope climate characteristics of longitudinal circulation in the equatorial Pacific Ocean were diagnosed and studied. The results showed that the annual variation and interannual variation characteristics of Walker circulation in east-west direction in the equatorial Pacific Ocean were that the intensity and scope existed 5 and 15-16 years oscillatory periods,and the position had 4,12 years oscillatory periods.

Analysis on the Climatic Characteristics of High and Low Temperature in the East of Hexi Corridor in Recent 50 Years

[Objective] The research aimed to provide the certain theory basis for the accurate forecast and early warning of high and low temperature in the east of Hexi Corridor.[Method] Based on the high(the daily highest temperature ≥35 ℃) and low(the daily lowest temperature ≤-20 ℃) temperature data in five observatories in the east of Hexi Corridor during 1960-2009,the temporal and spatial distribution,intensity,continuity and circulation situation of high and low temperature were analyzed in detail by using the statistical method.[Result] The high temperature weather in the east of Hexi Corridor mainly happened in the edge of northeast desert,and the low temperature mainly happened in the mountain zone where the altitude was higher and the edge of north desert.As the climate became warm,the high temperature days showed the weak increase trend,and the intensity strengthened.The low temperature days showed the obvious decrease trend,and the intensity weakened.The high temperature weather mainly occurred in June,August,and the low temperature mainly occurred in January,February,December.The high and low temperature weather had the durative characteristic.The strong high and low temperature mainly occurred in the durative time of high and low temperature.The high temperature weather appeared in the zone where was controlled and affected by the subtropical high.The low temperature weather appeared in the zone where the strong cold air accumulated and invaded.[Conclusion] The research had the extremely important significance on servicing for the agriculture,preventing and reducing the natural disasters,promoting the local economic development.

CLIMATIC CHARACTERISTICS OF THE ONSET OF SOUTH CHINASEA SUMMERMONSOON II.INTER-DECADAL VARIATION

By using the 40-year NCEP (1958-1997) grid point reanalysis meteorological data, we analyzed the inter-decadal variation on the climatic characteristics of the onset of South China Sea summer monsoon. The results are as follows. (1) There was great difference on the onset date of the SCS summer monsoon between the first two decades and the last two decades. It was late on the 6th pentad of May for the first two decades and was on the 4th and 5th pentad of May for the next two decades. (2) Except for the third decade (1978-1987), the establishment of the monsoon rainfall was one to two pentads earlier than the onset of the summer monsoon in all other three decades. (3) The onset of the SCS monsoon is the result of the abrupt development and eastward advancement of the southwesterly monsoon over the Bay of Bengal. The four-decade analysis shows that there were abrupt development of the southwesterly monsoon over the Bay of Bengal between the 3rd and 4th pentad of May, but there was great difference between its eastward movement and its onset intensity. These may have important effect to the earlier or later onset of the SCS summer monsoon. (4) During the onset of the SCS summer monsoon, there were great difference in the upper and lower circulation feature between the first two and the next two decades. At the lower troposphere of the first two decades, the Indian-Burma trough was stronger and the center of the subtropical high was located more eastward. At the upper troposphere, the northward movement of the center of subtropical high was large and located more northward after it landed on the Indo-China Peninsula. After comparison, we can see that the circulation feature of the last two decades was favorable to the establishment and development of the SCS summer monsoon.

Analysis on Climatic Characteristics of the Precipitation Anomaly in Southwest China in Recent 60 Years

[Objective] The research aimed to analyze temporal-spatial distribution characteristics of the precipitation anomaly in southwest China from 1951 to 2010. [Method] Based on monthly precipitation data at 44 stations of southwest China and 160 stations of China from 1951 to 2010, by using EOF analysis, wavelet analysis and composite analysis, monthly and seasonal change rules of the precipitation in southwest China were analyzed. Corresponding spatial-temporal distribution characteristics of the precipitation in drought and flood years were studied. Temporal-spatial distribution characteristics of the precipitation anomaly in southwest China in recent 60 years were revealed. [Result] Seasonal distribution of the precipitation in southwest China was uneven and was typical single-peak type. Precipitation concentrated from May to September, and peak appeared in July. In recent years, rainfall in autumn significantly became less, while that in other seasons had no obvious change. Precipitation in summer had the cycle of 14 years, another for 6 years and 3-4 years of periodic oscillations. In wet years, precipitation in southwest China had same phase with that in southern China, and anti-phase with that in the junction of Qinghai, Gansu, Xinjiang and Tibet. In dry years, precipitation in southwest China had same phase with that in the eastern part of northwest China and northern China. [Conclusion] The research provided reference basis for prediction and pre-warning of the precipitation in the zone.

Study on Cloud Change Trend in Southern China under the Influence of Climate Warming

[ Objective] The research aimed to study influences of the climate warming on cloudage and cloud-like structure in southern China. [ Method] Annual average temperature, total cloudage and low cloudage in Gan County, Nankang, Shangyou and Xinfeng of southern Jiangxi from 2004 to 2011 were selected. Influences of the annual average temperature change on annual average total cloudage, annual average low cloudage and cloud-like structure in southern Jiangxi were analyzed. [ Result] Climate warming was affecting cloudage and cloud-like structure in southern China. When annual average temperature rose, annual average total cloudage and low cloudage both presented decrease trends. When annual av- erage temperature declined, annual average total cloudage and low cloudage both presented rise trends. When annual average temperature was equal to that in prior year at low point, annual average total cloudage and low cloudage increased. Annual average low cloudage was different in mountain area and basin. Influences of the annual average temperature on annual average total cloudage and low cloudage in basin at the low alti- tude presented slow fluctuation form, and had severe influence on that in mountain area at the high altitude. Rise of the annual average temperature had larger influence on high cloudage, while decline of the annual average temperature had larger influence on annual average low cloudage. Under different weather situations, formation and disappearance change of the low cloud had different manifestation forms. [ Conclusion] The research provided scientific basis for studying changes of the cloudage and cloud-like structure in southern China as climate warming.

CHARACTERISTICS OF THE MERIDIONALLY ORIENTED SHEAR LINES OVER THE TIBETAN PLATEAU AND ITS RELATIONSHIP WITH RAINSTORMS IN THE BOREAL SUMMER HALF-YEAR

In this paper,European Center for Medium-Range Weather Forecasts(ECMWF)Reanalysis-Interim(ERAInterim)data and daily precipitation data in China from May to October during 1981-2016 are used to study the climatic characteristics of the meridionally oriented shear lines(MSLs)over the Tibetan Plateau(TP).The relationship between the MSL and rainstorms in the eastern TP and neighboring areas of the TP during the boreal summer half-year is also investigated.An objective method,which uses a combination of three parameters,i.e.the zonal shear of the meridional wind,the relative vorticity and the zero line of meridional wind,is adopted to identify the shear line.The results show that there are two high-occurrence centers of MSL.One is over the central TP(near 90°E)and the other is over the steep slope area of the eastern TP.Fewer MSLs are found along the Yarlung Zangbo River over the western TP and the southern Tibet.There are averagely 42.2 MSL days in each boreal summer half-year.The number of MSL days reaches the maximum of 62 in 2014 and the minimum of 22 in 2006.July and October witness the maximum of 10.2 MSL days/year and the minimum of 4.2 MSL days/year,respectively.The annual number of the MSL days shows periodicities of 2-4 and 4-6 years,which is quite similar to those of the MSL rainstorm days.In the neighboring areas of the TP,nearly56%of the MSLs lead to rainstorms,and nearly 40%of rainstorms are caused by the MSLs,indicating a close relationship between the MSLs and rainstorms in this region.