Temporal and Spatial Characteristics of Climate Changes in the Urumqi River Basin of Tianshan Mountain over 50 years

Based on the meteorological data during 1959-2008 from five representative weather stations in the Urumqi River Basin and surrounding areas,the regional characteristics of temperature and precipitation in the basin featuring multi-climatic zones were studied by means of some methods including wavelet analysis.As was shown in the results,the temperature in the whole Urumqi River Basin demonstrated a significant upward trend.The temperature increase particularly in autumn and winter made the greatest contribution to the marked ascent.The interdecadal temperature in the basin showed a tendency to decline before the period during 1970s-1980s while it was on the rise after 1990s on the whole.The most concentrated period of temperature mutations was in the late 1990s.At the same time,the precipitation also showed an escalating trend,which experienced a stage of unanimous upward trend after 1990s.The most concentrated period of precipitation mutations was in the early 1990s.

Analysis of vulnerability and resilience to climate change induced shocks in North Shewa, Ethiopia

This article analyzes the vulnerability and resilience levels of farm households in North Shewa, Ethiopia, using a survey of 452 households. Agro ecological based classification was done to analyze vulnerability to climate change induced shocks. Integrated vulnerability analysis approach was employed to develop indexes for socioeconomic and biophysical indicators. The indicators have been classified into adaptive capacity, exposure and sensitivity to climate change impact. Then Principal Component Analysis was used to compute vulnerability index of each agro ecological zone. The result shows that farmers living in the highland areas were very much vulnerable to natural shocks compared to those living in the lowland area. In order to identify and analyse the determinants of resilience to climate change impacts, ordered probit model was used. Households were classified into three categories based on the time they take to bounce back after natural shocks. The model outputs indicate that farmers with better investment on natural resource management, access to market, better social network, access to credit, preparedness, saving liquid assets, access to irrigation and better level of education exhibited greater level of resilience during and after climate change induced shocks.

Analysis on Climate Change in Zhucheng City of Shandong Province in Recent 50 Years

[Objective[ The aim was to analyze the characteristics of climate changes in Zhucheng City in Shandong Province from 1961 to 2010. [Method] The temperature and precipitation in Zhucheng City from 1961 to 2010 were chosen to analyze its annual and seasonal changes based on linear trend estimation method. [ Result]The average temperature in recent 50 years rose at a speed of 0.383 ℃/10 a. The mean temperature in each season increased. As the temperature increase span in winter 〉 autumn 〉 spring 〉 summer, the mean precipitation in recent 50 years de- creased at a speed of 18.7 mm/10 a, increased in spring and winter but decreased in summer and autumn. Temperature reduced most distinctly in summer at a speed of 20.9 mm/10 a. The abnormal temperature reduction happened only once in Zhucheng in recent 50 years. Abnormal high temperature happened in seven years, after 1990s. In recent 50 years, only six years had abnormal precipitation and the annual total precipitation decreased, which indicated that the spatial distribution of precipitation was uneven. [ Conclusionl The study provided reference for the increasing accuracy of temperature and of precipitation report.

Projected Changes in the Climate Zoning of Côte d’Ivoire

This study assesses the projected changes in the climate zoning of Côte d’Ivoire using the hierarchical classification of principal components (HCPC) method applied to the daily precipitation data of an ensemble of 14 CORDEX-AFRICA simulations under RCP4.5 and RCP8.5 scenarios. The results indicate the existence of three climate zones in Côte d’Ivoire (the coastal, the centre and the north) over the historical period (1981-2005). Moreover, CORDEX simulations project an extension of the surface area of drier climatic zones while a reduction of wetter zones, associated with the appearance of an intermediate climate zone with surface area varying from 77,560 km2 to 134,960 km2 depending on the period and the scenario. These results highlight the potential impacts of climate change on the delimitation of the climate zones of Côte d’Ivoire under the greenhouse gas emission scenarios. Thus, there is a reduction in the surface areas suitable for the production of cash crops such as cocoa and coffee. This could hinder the country’s economy and development, mainly based on these cash crops.

Climate Change Characteristics and Return Periods of Heavy Precipitation in the Northeast Side of Qinghai-Tibet Plateau

[ Objective] The study aimed to discuss analyze climate change characteristics and return periods of heavy precipitation in the northeast side of Qinghai-Tibet Plateau. [ Method] Based on the data of daily precipitation from 1943 to 2008 in 6 representative meteorological stations in Linxia located in the northeast side of Qinghai-Tibet Plateau, the climate change characteristics of heavy precipitation were analyzed, and the return periods of heavy precipitation were calculated by Pearson-Ill probability distribution method. [ Result] Days of heavy precipitation in Linxia region in- creased conspicuously since the 1990s. The return periods of heavy precipitation in the six stations on August 20, 2008 were consistent with the re- sults of artificial estimation. [ Conclusion] The research could provide scientific references for the reasonable utilization of climate resources, disas- ter prevention and rational arranqement of anricultural plantina svstems in Linxia reaion.

Analysis to driving forces of land use change in Lu’an mining area

By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining area as an example, the specific impact factors of coal mine were comprehensively evaluated and analyzed in order to carry out qualitative and quantitative analysis for the driving force of mining-land use change. The principal component analysis shows that the social and economic development in mining area from 2000 to 2007 demonstrates continuous accelerate trends, and the impacts of its overall driving force to land use change are increased gradually. The socio-economic factors have more impacts to mining-land use change than those of the natural resources. The main driving force of mining-land use change also include population, technological progress and policy.

Spike-Grain Structure of Winter Wheat and Its Climate Change Tendency in Jiangsu

To scientifically respond to the impact of climate change on winter wheat production,spike-grain structure data of winter wheat at Jiangsu Phenometeorological Observatory were taken as the sample. Based on agrometeorology,statistics and GIS analytical technique,status quo of spike-grain structure of winter wheat in Jiangsu and its climate change tendency were analyzed systemically. The results showed that climate change rate( CTR) of mature spike number( NS) was between-53. 37 and 256. 51 spikes/( m^2·10 a),and mean of whole province was 21.45 spikes/( m^2·10 a). CTR of number of grains per panicle( GNPS) was between-0. 58 and 12. 52 grains/( spike·10 a),and mean of whole province was 2. 39 grains/( spike·10 a). CTR of thousand-grain weight( TSW) was between-1. 65 and 16. 39 g/( 1 000 grains·10 a),and mean of whole province was 2. 86 g/( 1 000 grains·10 a). For the means of NS,GNPS,and TSW in whole province,they all showed the increasing trend with climate change,and they were just unbalanced among regions. Climate change induced the variation of meteorological conditions during growth period of winter wheat in Jiangsu. The variation of unity yield( UY) caused by this kind of change trend only accounted for-4. 32%-17. 23% of that in normal climate years,and mean of whole province was 6. 4%. That is to say,comprehensive impact of meteorological condition was favorable for improving the yield of winter wheat with climate change. Therefore,coordination level of winter wheat growth and real-time meteorological conditions could be regulated by breeding the varieties with wide climate suitability,regulating sowing date and density according to local production and management level,rational fertilization and applying growth regulator,to mitigate the adverse effects of climate change on winter wheat production,and reach high yield and quality.

Mapping Vulnerability to Climate Change in Malawi: Spatial and Social Differentiation in the Shire River Basin

This article analyses vulnerability to climate related shocks across five districts in the shire river basin of Malawi. The analysis employs an indicator approach that integrates biophysical and socio-economic indices. Principal component statistical analysis was used to calculate an index for adaptive capacity, sensitivity and exposure to climate impact for each of the five districts. These indices were aggregated to develop a vulnerability index differentiated also by gender for the surveyed districts. The results showed that Chikwawa, Machinga and Blantyre appear to be more vulnerable to climate related shocks compared with Mwanza and Zomba. Women in Chikwawa are also found to be the most susceptible to the climate hazards impacts. To reduce vulnerability to climate impact, the study suggests that the national adaptation strategies adopted by the government should be mainstreamed into specific local adaptation actions that can be accessible and adopted by the community. Specific emphasis should be given to the improvement of women’s welfare through better access to productive assets and resources.

Characteristics of Central Southwest Asian Water Budgets and Their Impacts on Regional Climate

Water budgets terms, evapotranspiration (E), precipitation (P), runoff (N), moisture convergence (MC) and both surface as well as atmospheric residual terms have been computed with National Centers for Environmental Prediction (NCEP) (1948-2007) and European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-40 (1958-2001) reanalysis data sets for Central Southwest Asia (CSWA).The domain of the study is 45° - 75°E & 25° - 40°N. Only the land area has been used in these calculations. It is noted in the comparison of both reanalysis data sets with Global Precipitation Climatology Centre (GPCC) that all three data sets record different precipitation before 1970. The maximum is from NCEP and the minimum with ERA-40. However, after 1970 all the data sets record almost the same precipitation. ERA-40 computes two phases of MC. Before 1975, the domain acts as a moisture source, whereas after 1975 it behaves as a moisture sink. The region CSWA is divided into six sub areas with rotational principle factor analysis and we distinguish them by different approached weather systems acting on each area. Finally, NCEP yearly precipitation is further divided into seasons;winter (November to April) and summer (May to October) and two phases have been noted. The variation in winter precipitation is more than summer during last 60-year analysis.

Analysis on Climatic Characteristics of High Temperature Weather in Longdong Region

Using meteorological data from 8 national basic meteorological observation stations in Qingyang City of Longdong region from 1972 to 2021,the causes and change characteristics of high-temperature weather were analyzed,and targeted countermeasures and suggestions were proposed for residents' production,life,and energy security supply affected by high-temperature weather.The results showed that①affected by global warming,the annual average temperature,annual average maximum temperature,annual extreme maximum temperature,days of daily maximum temperature≥30℃,and days of daily maximum temperature≥35℃in Longdong region were all showing an upward trend;②due to the different terrain and soil properties of the underlying surface,the increase in high temperature weather varied in different regions.Due to the influence of desert and hilly terrain,the frequency and days of high temperature occurrence were relatively high in the central and northern parts of Qingyang City.Due to the climate regulation of the Ziwuling Mountains,the days of high temperature in the central and southern parts was significantly less than that in the central and northern parts;③if the warm high pressure ridge on the Qinghai-Tibet Plateau developed strongly in summer,the temperature of the closed warm center reached 0-4℃on the 500 hPa of high-altitude weather map.If the warm air mass developed eastward,it often led to sustained high temperature weather in Longdong region;④when the El Nino phenomenon occurred,the subtropical high in the western Pacific developed strongly in summer,with a center located northward,which was stable,with little movement.It was dry,sunny,hot,and rainless in Longdong region,and the high temperature weather was more significant than that in normal years.

Perceiving the Trend of Terrestrial Climate Change during the Past 40 year(1978-2018)

In past few decades,climate has manifested numerous shifts in its trend.Various natural and anthropogenic factors have influenced the dynamics and the trends of climate change at longer time scale.To understand the long term climate fluctuations,we have analyzed forty years(1978-2018)data of ten climatic parameters that are responsible to influence the climate dynamics.The parameters involved in the present study are total solar irradiance(TSI),ultra violet(UV)index,cloud cover,carbon dioxide(CO2)abundances,multivariate(ENSO)index,volcanic explosivity index(VEI),global surface temperature(GST)anomaly,global sea ice extent,global mean sea level and global precipitation anomaly.Using the above mentioned climate entities;we have constructed a proxy index to study the quantitative measure of the climate change.In this process these indicators were aggregated to a single proxy index as global climate index(GCI)that has measured the strength of present climate change in semblance with the past natural variability.To construct GCI,the principal component analysis(PCA)has been used on yearly based data for the period 1978-2018.Actually PCA is a statistical tool with which we can reduce the dimensionality of the data and it retains most of the variation in the new data set.Further,we have confined our study to natural climate drivers and anthropogenic climate drivers.Our result has indicated that the strongest climate change has been occurred globally by the end of the year 2018 in comparison to late 1970’s natural variability.

Landscape Changes from 1974 to 1995 in the Upper Minjiang River Basin, China

Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes.

On arable land changes in Shandong Province and their driving forces

The decrease of total cultivated area and the lower per capita available arable land resource are now serious problems in Shandong Province, a major agricultural province in China. These problems will become more serious along with the further development of economy. In this paper, based on the statistical information at provincial and county levels, the changes of arable land in Shandong Province and their driving forces during the last 50 years are analyzed. The general changing trends of arable land and per capita available arable land are reducing, and the trends of decrease will continue when the economy is developing. The result of GIS spatial analysis shows that the change of the arable land use in Shandong Province has a regional difference. Eight variables having influences on cultivated land change are analyzed by principal component analysis. The results show that the dynamic development of economy, pressure of social system and progress of scientific techniques in agriculture are the main causes for cultivated land reduction. The principal factors which can be considered as driving forces for arable land change include per capita net living space, total population and per ha grain yield. By using regressive equation, along with analysis on population growth and economic development, cultivated areas in Shandong Province in 2005 and 2010 are predicted respectively. The predicted cultivated areas in Shandong will be 6435.47 thousand hain 2005 and 6336.23 thousand ha in 2010 respectively.

Urban Land Use Change Detection Using Multisensor Satellite Images

Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in developed urban area in the coastal regions; therefore, there is an urgent need to effectively detect and monitor the land use changes and provide accurate and timely information for planning and management. In this study a method combining principal component analysis (PCA) of multisensor satellite images from SPOT (systeme pour l'observation de la terre or earth observation satellite)-5 multispectral (XS) and Landsat-7 enhanced thematic mapper (ETM) panchromatic (PAN) data, and supervised classification was used to detect and analyze the dynamics of land use changes in the city proper of Hangzhou. The overall accuracy of the land use change detection was 90.67% and Kappa index was 0.89. The results indicated that there was a considerable land use change (10.03% of the total area) in the study area from 2001 to 2003, with three major types of land use conversions: from cropland into built-up land, construction site, and water area (fish pond). Changes from orchard land into built-up land were also detected. The method described in this study is feasible and useful for detecting rapid land use change in the urban area.

Drought Forecasting in a Semi-arid Watershed Using Climate Signals:a Neuro-fuzzy Modeling Approach

Large-scale annual climate indices were used to forecast annual drought conditions in the Maharlu-Bakhtegan watershed,located in Iran,using a neuro-fuzzy model.The Standardized Precipitation Index(SPI) was used as a proxy for drought conditions.Among the 45 climate indices considered,eight identified as most relevant were the Atlantic Multidecadal Oscillation(AMO),Atlantic Meridional Mode(AMM),the Bivariate ENSO Time series(BEST),the East Central Tropical Pacific Surface Temperature(NINO 3.4),the Central Tropical Pacific Surface Temperature(NINO 4),the North Tropical Atlantic Index(NTA),the Southern Oscillation Index(SOI),and the Tropical Northern Atlantic Index(TNA).These indices accounted for 81% of the variance in the Principal Components Analysis(PCA) method.The Atlantic surface temperature(SST:Atlantic) had an inverse relationship with SPI,and the AMM index had the highest correlation.Drought forecasts of neuro-fuzzy model demonstrate better prediction at a two-year lag compared to a stepwise regression model.

Modeling nonstationary extreme wave heights in present and future climates of Greek Seas

In this study the generalized extreme value （GEV） distribution function was used to assess nonstationarity in annual maximum wave heights for selected locations in the Greek Seas, both in the present and future climates. The available significant wave height data were divided into groups corresponding to the present period （1951-2000）, a first future period （2001-2050）, and a second future period （2051-2100）. For each time period, the parameters of the GEV distribution were specified as functions of time-varying covariates and estimated using the conditional density network （CDN）. For each location and selected time period, a total number of 29 linear and nonlinear models were fitted to the wave data, for a given combination of covariates. The covariates used in the GEV-CDN models consisted of wind fields resulting from the Regional Climate Model version 3 （RegCM3） developed by the International Center for Theoretical Physics （ICTP） with a spatial resolution of 10 km ×10 km, after being processed using principal component analysis （PCA）. The results obtained from the best fitted models in the present and future periods for each location were compared, revealing different patterns of relationships between wind components and extreme wave height quantiles in different parts of the Greek Seas and different periods. The analysis demonstrates an increase of extreme wave heights in the first future period as compared with the present period, causing a significant threat to Greek coastal areas in the North Aegean Sea and the Ionian Sea.

Identification and analysis of serum samples by surface-enhanced Raman spectroscopy combined with characteristic ratio method and PCA for gastric cancer detection

This study aimed to explore the application of surface-enhanced Raman scattering(SERS)in the rapid diagnosis of gastric cancer.The SERS spectra of 68 serum samples from gastric cancer patients and healthy volunteers were acquired.The characteristic ratio method(CRM)and principal component analysis(PCA)were used to differentiate gastric cancer serum from normal serum.Compared with healthy volunteers,the serum SERS intensity of gastric cancer patients was relatively high at 722 cm^(-1),while it was relatively low at 588,644,861,1008,1235,1397,1445 and 1586 cm^(-1).These results indicated that the relative content of nucleic acids in the serum of gastric cancer patients rises while the relative content of amino acids and carbohydrates decreases.In PCA,the sensitivity and specificity of discriminating gastric cancer were 94.1%and 94.1%,respectively,with the accuracy of 94.1%.Based on the intensity ratios of four characteristic peaks at 722,861,1008 and 1397 cm^(-1),CRM presented the diagnostic sensitivity and specificity of 100%and 97.4%,respectively,and the accuracy of 98.5%.Therefore,the three peak intensity ratios of I_(722)/I_(861),I_(722)/I_(1008)and I_(722)/I_(1397)can be considered as biologicalfingerprint information for gastric cancer diagnosis and can rapidly and directly reflect the physiological and pathological changes associated with gastric cancer development.This study provides an important basis and standards for the early diagnosis of gastric cancer.

Review of the sesame breeding by characteristic analysis on the varieties in Henan province

The results of characteristic comparison and principal component analysis showed that the major .characteristics of sesame varieties in Henan province were improved in the past decades. The sesame breeding works in the province were focused on the collection and the screening of the native germplasms from 1950 to 1969 and the mean values of the variety characteristics were the lowest. In 1970s,the pedigree breeding was mainly conducted,which resulted in the release of varieties of various types with better traits. During 1980s,the hybridization breeding was carried out dominantly with the varieties possessing fine traits. Since 1990,there were no better varieties released. To make new progresses,it is essential to renew the breeding method and at the same time to introduce and create special germplasms to widen the genetic background.

Influence of Regular Wave and Ship Characteristics on Mooring Force Prediction by Data-Driven Model

The study of mooring forces is an important issue in marine engineering and offshore structures.Although being widely applied in mooring system,numerical simulations suffer from difficulties in their multivariate and nonlinear modeling.Data-driven model is employed in this paper to predict the mooring forces in different lines,which is a new attempt to study the mooring forces.The height and period of regular wave,length of berth,ship load,draft and rolling period are considered as potential influencing factors.Input variables are determined using mutual information(MI)and principal component analysis(PCA),and imported to an artificial neural network(NN)model for prediction.With study case of 200 and 300 thousand tons ships experimental data obtained in Dalian University of Technology,MI is found to be more appropriate to provide effective input variables than PCA.Although the three factors regarding ship characteristics are highly correlated,it is recommended to input all of them to the NN model.The accuracy of predicting aft spring line force attains as high as 91.2%.The present paper demonstrates the feasibility of MI-NN model in mapping the mooring forces and their influencing factors.

Study on Characteristics of Climatic Variation in Yanhe Watershed during 1974-2004

[Objective] The aim was to study the climate changes of Yanhe watershed during 1974-2004. [Method] The monthly temperature and precipitation during 1974-2004 in seven representative stations in Yanhe watershed were chosen. By dint of climate statistics analysis method, accumulated anomaly and signal/noise ratio method, the regional temperature and precipitation changes in recent 31 years were expounded and its changes features and the year having climate mutation were found out. [Result] The climate changes in Yanhe watershed in recent 31 years rose at a speed of 0.44 ℃/10 a. The temperature increase range enlarged after 1990s. Precipitation decreased at a speed of 26.3 mm/10 a. Precipitation reduced most distinctly in summer and autumn, and the reduction range enlarged in 1990s. 1996 was the year of abrupt temperature changes year in the region. 1993 was the year of temperature transition year. 1994 was the year of precipitation mutation year. 1990 was the year of precipitation transition year. [Conclusion] The study provided references for the agricultural production, life and disaster pre-warning in Yanhe watershed.