Spatio-Temporal Analysis of Drought Indicated by SPEI over Northeastern China

Drought is a natural extreme climate event which occurs in most parts of the world. Northeastern China is one of the major agricultural production areas in China and also a typical vulnerable climate zone. To understand the spatio-temporal characteristics of drought over northeastern China, we first assessed the trends of precipitation and temperature. Drought events were then characterized by Standardized Precipitation Evapotranspiration Index over various temporal scales. The Trend Free Prewhitening Mann–Kendall test and distinct empirical orthogonal function, were used to investigate the trends and spatio-temporal patterns of droughts. The results indicate precipitation increasing trends are mostly detected in Heilongjiang and Jinling provinces, however, the majority of the trends are insignificant. Temperature increasing trends are detected over the entire northeastern China and most of them are significant. Decreasing drought trends are observed in Heilongjiang province and some bordering area in Jilin province, whereas increasing trends are noticed in Liaoning province and some bordering area in Jilin province. Two main sub-regions of drought variability—the Liaohe River Plain and the Second Songhua River basin (LS region), and the Songnen Plain and the Lesser Hinggan Mountains (SL region) are identified, and the detected droughts for the two sub-regions correspond well with recorded drought loss. The results will be beneficial for regional water resource management and planning, agriculture production, and ecosystem protection in northeastern China.

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Spatio-temporal analysis and visualisation of the anthrax epidemic situation in livestock in Kazakhstan over the period 1933-2016

Geospatial health ◽

10.4081/gh.2017.589 ◽

2017 ◽

Cited By ~ 1

Author(s):

Sarsenbay K. Abdrakhmanov ◽

Yersyn Y. Mukhanbetkaliyev ◽

Fedor I. Korennoy ◽

Bolat Sh. Karatayev ◽

Aizada A. Mukhanbetkaliyeva ◽

...

Keyword(s):

Temporal Trends ◽

Small Ruminants ◽

Temporal Analysis ◽

Space Time ◽

Decision Makers ◽

Annual Number ◽

Spatio Temporal ◽

The Republic ◽

Increasing Trends ◽

Historical Periods

An analysis of the anthrax epidemic situation among livestock animals in the Republic of Kazakhstan over the period 1933-2016 is presented. During this time, 4,064 anthrax outbreaks (mainly in cattle, small ruminants, pigs and horses) were recorded. They fall into five historical periods of increase and decrease in the annual anthrax incidence (1933-1953; 1954-1968; 1969-1983; 1984- 2001; and 2002-2016), which has been associated with changes in economic activity and veterinary surveillance. To evaluate the temporal trends of incidence variation for each of these time periods, the following methods were applied: i) spatio-temporal analysis using a space-time cube to assess the presence of hotspots (i.e., areas of outbreak clustering) and the trends of their emergence over time; and ii) a linear regression model that was used to evaluate the annual numbers of outbreaks as a function of time. The results show increasing trends during the first two periods followed by a decreasing trend up to now. The peak years of anthrax outbreaks occurred in 1965-1968 but outbreaks still continue with an average annual number of outbreaks of 1.2 (95% confidence interval: 0.6-1.8). The space-time analysis approach enabled visualisation of areas with statistically significant increasing or decreasing trends of outbreak clustering providing a practical opportunity to inform decision-makers and allowing the veterinary services to concentrate their efforts on monitoring the possible risk factors in the identified locations.

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Analysis of Non-Parametric Trend and Climatic Parameter Homogeneity Tests in a Data-scarce Region: A Spatio-Temporal Perspective in the Tawang River Basin, Eastern Himalayas

10.21203/rs.3.rs-1107455/v1 ◽

2021 ◽

Author(s):

Juna Probha Devi ◽

Chandan Mahanta ◽

Anamika Barua

Keyword(s):

Water Resource Management ◽

Management Strategies ◽

Kendall Test ◽

Climate Impact ◽

Mean Annual Precipitation ◽

Homogeneity Test ◽

Eastern Region ◽

Positive Trend ◽

Temporal Perspective ◽

Spatio Temporal

Abstract This study is aimed at studying long–term historical and future (1950-2099) trends for the RCP 4.5 and RCP 8.5 on approximately 30-year timescale at annual and seasonal for precipitation and at annual, seasonal, monthly, and diurnal temperature range (DTR) for temperature maximum (T_max), temperature minimum (T_min) variations using statistical trend analysis techniques– Mann–Kendall test (MK) and Sen's slope estimator (S) and the homogeneity test using Pettitt’s test. The study is carried out in three spatial points across the Tawang Chu in the district of Tawang, Arunachal Pradesh. The summer mean precipitation for RCP 4.5 (2006-2065) shows a positive trend with a rise in precipitation between 1.56 mm to 9.94 mm in all the study points. The mean annual precipitation statistics for all the points show an increase of RCP 4.5 in 2006-2052 and 2053-2099 timescale. Both RCP 4.5 and 8.5 scenarios exhibit a uniform rise in T_min and T_max during investigation. For all the points, the results likewise reveal a rising trend in mean annual T_min and T_max. Still, the inter-decadal temperature statistical analysis shows that the increase in mean annual T_min is greater than the increase in T_max, indicating a decreasing trend in DTR. It is anticipated that this study's outcomes will contribute to a better understanding of the relationship between change in climate and the regional hydrological behaviour and will be benefitting the society to develop a regional strategy for water resource management, can serve as a resource for climate impact research scope- assessments, adaptation, mitigation, and disaster management strategies for India's north-eastern region.

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Long–term spatio–temporal warming tendency in the Vietnamese Mekong Delta based on observed and high–resolution gridded datasets

10.34154/2019-ejcc-0101-01-16/euraass ◽

2019 ◽

pp. 01-16

Author(s):

Dang Nguyen Dong Phuong ◽

Dang Kien Cuong ◽

Duong Ton Dam ◽

Nguyen Kim Loi

Keyword(s):

High Resolution ◽

Statistical Tests ◽

Mekong Delta ◽

Kendall Test ◽

Trend Detection ◽

Homogeneity Test ◽

Spatio Temporal ◽

Temperature Records ◽

Slope Estimator ◽

Increasing Trends

The Vietnamese Mekong Delta is among the most vulnerable deltas to climate–related hazards across the globe. In this study, the annual mean and extreme temperatures from 11 meteorological stations over the Vietnamese Mekong Delta were subjected to normality, homogeneity and trend analysis by employing a number of powerful statistical tests (i.e. Shapiro–Wilk, Buishand Range test, classical/modified Mann–Kendall test and Sen’s slope estimator). As for spatio–temporal assessment, the well–known (0.5° × 0.5°) high–resolution gridded dataset (i.e. CRU TS4.02) was also utilized to examine trend possibilities for three different time periods (i.e. 1901–2017, 1951–2017 and 1981–2017) by integrating spatial interpolation algorithms (i.e. IDW and Ordinary Kriging) with statistical trend tests. Comparing the calculated test–statistics to their critical values (a = 0.05), it is evident that most of the temperature records can be considered to be normal and non–homogeneous with respect to normality and homogeneity test respectively. As for temporal trend detection, the outcomes show high domination of significantly increasing trends. Additionally, the results of trend estimation indicate that the magnitude of increase in minimum temperature was mostly greater than mean and maximum ones and the recent period (1981–2017) also revealed greater increasing rates compared to the entire analyzed period and second half of the 20th century. In general, these findings yield various evident indications of warming tendency in the Vietnamese Mekong Delta over the last three decades.

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Spatio-temporal Variability and Trends in Rainfall and Temperature in Anger watershed, Southwestern Ethiopia

Journal of Applied Geospatial Information ◽

10.30871/jagi.v5i1.2825 ◽

2021 ◽

Vol 5 (1) ◽

pp. 462-472

Author(s):

Gemechu Yigezu Ofgeha ◽

Muluneh Woldetsadik Abshire

Keyword(s):

Temporal Trends ◽

Kendall Test ◽

Annual Rainfall ◽

Small Scale ◽

Rainfall Trend ◽

High Rainfall ◽

Southwestern Ethiopia ◽

Spatio Temporal ◽

Small Scale Farmers ◽

Increasing Trends

Insights to broadly argued research gap on lack of climate studies at micro-scale considering unique features of an area, this paper intended to examine agro-ecological level spatio-temporal trends and variability in rainfall and temperature in Anger watershed of southwestern Ethiopia. The gridded data managed by the Ethiopia National Meteorological Services Agency (NMSA) for 1983-2018 were used. The Mann-Kendall test for trend analysis and different variability measures were used. Questionnaire and FGD data on community perceptions gathered from 214 households and elders were analysed descriptively and qualitatively. The study reveals the consistent increasing trends in temperature; and high variability and insignificant but increasing rainfall trend. The trends and variability show spatio-temporal differences along agro-ecologies. The watershed is characterized by moderate to high rainfall coefficient of variations, significant years of high rainfall concentration, and considerable negative annual rainfall anomalies; that the variability was severe in woinadega followed by kolla agro-ecology. Although, the perceptions on trends, variability and its implications show difference across agro-ecology, the propensity to increased temperature, unclear rainfall trend and significant inter-annual and seasonal variability were witnessed. Unpredictability of rainfall time, concentrations in kiremt, and unexpected rain during harvesting was major challenges resulting multifaceted impacts on the small-scale farmers’ livelihoods.

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Analysis of Temporal and Spatial Characteristic of Temperature Change over the Last 45 Years in Northeastern China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.1367 ◽

2012 ◽

Vol 518-523 ◽

pp. 1367-1370 ◽

Cited By ~ 1

Author(s):

Wei He ◽

Ren Cang Bu ◽

Yuan Man Hu ◽

Zai Ping Xiong ◽

Miao Liu

Keyword(s):

Kendall Test ◽

Northern Region ◽

Northeastern China ◽

Spatial Characteristic ◽

Weighted Interpolation ◽

Spatiotemporal Trends ◽

Mean Temperature ◽

Mann Kendall Test ◽

Inverse Distance Weighted Interpolation ◽

Increasing Trends

Based on the temperature datasets from 1961 to 2005 at 96 meteorological stations, the spatiotemporal trends of climate change were analyzed in annual and seasonal timescales, by a linear and regression model, cumulative anomaly method, Mann-Kendall test and inverse distance weighted interpolation methods, in Northeastern China. The results showed that: (1) Both annual and seasonal mean temperature showed increasing trends, the annual mean temperature have rised by 0.07°Cwith a rate of 0.38°C/decade, and the highest increasing rates of temperature occured in the winter (0.53°C/decade) and lowest one was the in the summer (0.23°C/decade). (2) The results of Mann-Kendall test on temperature showed that the annual and seasonal mean temperature significantly increased at 95% of confidence. The climate jump of annual mean temperature took place in 1987, and the climate jumps of spring, summer, autumn and winter mean temperature occurred in 1988, 1993, 1989 and 1981, respectively, and these results were confirmed by the cumulative anomaly curve. (3) The higher the latitude, the more obvious the increasing trend, especially in winter, and therefore the temperature increased in most parts of the Northeastern China.However, the increasing trends in the northern region of the Da Hinggan Moutains and Xiao Hinggan Moutains were the most obvious.

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Spatio-temporal analysis of precipitation pattern and trend using standardized precipitation index and Mann–Kendall test in coastal Andhra Pradesh

Modeling Earth Systems and Environment ◽

10.1007/s40808-021-01262-w ◽

2021 ◽

Author(s):

Mirza Razi Imam Baig ◽

Shahfahad ◽

Mohd Waseem Naikoo ◽

Aijaz Hussain Ansari ◽

Shakeel Ahmad ◽

...

Keyword(s):

Andhra Pradesh ◽

Standardized Precipitation Index ◽

Kendall Test ◽

Temporal Analysis ◽

Precipitation Index ◽

Precipitation Pattern ◽

Mann Kendall Test ◽

Spatio Temporal

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Spatio-temporal analysis of Maximum temperature over Iraq

Al-Mustansiriyah Journal of Science ◽

10.23851/mjs.v29i1.257 ◽

2018 ◽

Vol 29 (1) ◽

pp. 1

Author(s):

Aws Ali Al Khudhairy

Keyword(s):

Temporal Trends ◽

Surface Air Temperature ◽

Kendall Test ◽

Temporal Analysis ◽

Maximum Temperature ◽

Positive Trend ◽

Seasonal Temperature ◽

The North ◽

Four Seasons ◽

Spatio Temporal

Monthly Maximum surface air temperature at 23 stations in Iraq were analyzed for temporal trends and spatial variation during 1980-2015.Seasonal and annual temperature was analyzed using Mann-Kendall test to detect the significant trend .The results of temporal analysis showed that during winter ,spring , summer and Autumn have a positive trend in all the parts of Iraq. A tendency has also been observed towards warmer years, with significantly warmer summer and spring periods and slightly warmer autumn and winter, The highest increase is (3.9) oC in Basrah during the summer. The results of spatial analysis using the ArcGIS showed that the seasonal temperature can be divided into two or three distinct areas with high temperature in the south and decreasing towards north, where the trend of spatial temperature were decreasing from south to the north in all the four seasons.

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