scholarly journals Variability and time series trend analysis of temperature over 1981-2018 in semi-arid Borana zone, southern Ethiopia

2021 ◽  
Author(s):  
Mitiku Adisu Worku ◽  
Gudina Legese Feyisa ◽  
Kassahun Ture Beketie
Keyword(s):  
Climate Variability ◽  
Minimum Temperature ◽  
Spatial Scales ◽  
Warming Trend ◽  
Maximum Temperature ◽  
Southern Ethiopia ◽  
Mk Test ◽  
Temporal And Spatial ◽  
Borana Zone ◽  
Semi Arid

Abstract BackgroundUnderstanding the climate variability at local scale could help suggest local adaptation responses to manage climate driven impacts. This paper analyzed the variability and trends of temperature over the period 1981-2018 in semi-arid Borana zone of southern Ethiopia using Mann-Kendall (MK) test and inverse distance weighted (IDW) interpolation technique. Gridded (4 km * 4 km) daily temperature data was used to study variability at temporal and spatial scales. ResultsThe results revealed that monthly temperature shows a warming trend where February was the warmest month for both maximum and minimum temperature. Seasonally, the highest maximum and minimum temperatures were observed during Bega. Minimum temperature shows a warming trend during all seasons unlike maximum temperature. Both minimum and maximum temperature shows not significant warming trend at annual timescale. The later decades (20012018) have shown a warming trend compared to a period ahead especially for minimum temperature. The southwestern and southeastern areas across the zone were warmer than any other areas in the region during the studied period. ConclusionTemperature shows variability at shorter than longer timescales. There is a pronounced warming trend for minimum than maximum temperature. Warming condition advances from the northcentral parts towards the southwestern and southeastern areas. Internal variability was observed at temporal and spatial scales and therefore any adaptation responses to local climate variability should consider the microscale climate.

scholarly journals Trend Change Study of Climate Variables in Xin’anjiang-Fuchunjiang Watershed, China

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Muhammad Zaman ◽  
Guohua Fang ◽  
Kashif Mehmood ◽  
Muhammad Saifullah
Keyword(s):  
Minimum Temperature ◽  
Abrupt Change ◽  
Statistical Tests ◽  
Spatial Scales ◽  
Kendall Test ◽  
Precipitation Trend ◽  
Climate Variables ◽  
Serial Effect ◽  
Regional Basis ◽  
Temporal And Spatial

This study emphasizes the precipitation and the maximum and minimum temperature trend and presents the results of study in temporal and spatial scales, after performing statistical analysis of the Xin’anjiang-Fuchunjiang watershed. Statistical Mann Kendall and Theil Sen techniques were used to determine the trend and its magnitude, respectively, and for determining the start and abrupt change in the trend, Sequential Mann Kendall test has been performed. Furthermore, statistical tests were performed to determine the overall trend in the area at a regional basis. For the removal of the serial effect of the data, prewhitening technique is applied. In this study, statistical tests were performed at 1901–2013 precipitation and temperature series and then after detection of the change year precipitation data were divided into two different scenarios of 1901–1960 period and 1961–2013 period. The results showed that precipitation trend is insignificant while maximum and minimum temperature have increased during 1901–2013 period except for some stations of autumn and summer seasons.

scholarly journals ASSESSMENT OF LONG TERM CLIMATIC VARIABILITY OF UTTARAKHAND

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Sujeet Kumar ◽  
Shakti Suryavanshi
Keyword(s):  
Minimum Temperature ◽  
Monsoon Season ◽  
Climatic Variability ◽  
Kendall Test ◽  
Summer Season ◽  
Climatic Variables ◽  
Maximum Temperature ◽  
Mountain Areas ◽  
Mk Test ◽  
Increasing Trend

A trend analysis was performed for historic (1901-2002) climatic variables (Rainfall, Maximum Temperature and Minimum Temperature) of Uttarakhand State located in Northern India. In the serially independent climatic variables, Mann-Kendall test (MK test) was applied to the original sample data. However, in the serially correlated series, prewhitening is utilized before employing the MK test. The results of this study indicated a declining trend of rainfall in monsoon season for seven out of thirteen districts of Uttarakhand state. However, an increasing trend was observed in Haridwar and Udhamsingh Nagar districts for summer season rainfall. For maximum and minimum temperature, a few districts exhibited a declining trend in monsoon season whereas many districts exhibited an increasing trend in winter and summer season. Mountain dominated areas (as Uttarakhand state) are specific ecosystems, distinguished by their diversity, sensitivity and intricacy. Thus the variability of rainfall and temperature has a severe and rapid impact on mountainous ecosystems. Nevertheless, mountains have significant impacts on hydrology, which may further threaten populations living in the mountain areas as well as in adjacent, lowland regions.

scholarly journals Trend Analysis of Precipitation and Temperature over Different Districts of Karnataka: An Aid to Climate Change Detection and Cropping System Option

2020 ◽  
pp. 15-25
Author(s):  
S. Sridhara ◽  
Pradeep Gopakkali ◽  
R. Nandini
Keyword(s):  
Minimum Temperature ◽  
Monsoon Season ◽  
Cropping System ◽  
Weather Conditions ◽  
Kendall Test ◽  
Annual Rainfall ◽  
Maximum Temperature ◽  
Land Preparation ◽  
Mk Test ◽  
Increasing Trend

Aims: To know the rainfall and temperature trend for all the districts of Karnataka state to develop suitable coping mechanisms for changing weather conditions during the cropping season. Study Design: The available daily data of rainfall (1971-2011) and minimum and maximum temperature (1971-2007) for each district was collected from NICRA-ICAR website. A non-parametric model such as the Mann-Kendall (MK) test complemented with Sen’s slope estimator was used to determine the magnitude of the trend. Place and Duration of Study: The rainfall data of 41 years (1971-2011) and temperature data of 37 years (1971-2007) was collected for all 27 districts of Karnataka. Methodology: Basic statistics related to rainfall like mean, standard deviation (SD), the coefficient of variation (CV) and the percentage contribution to annual rainfall were computed for monthly and season-wise. Mann-Kendall test was used to detect trend for rainfall as well as temperature. Results: An increasing trend in rainfall during winter, monsoon and annual basis for all most all the districts of Karnataka and decreasing trend of rainfall during pre and post-monsoon season was noticed. An early cessation of rainfall during September month in all most all the districts of Karnataka was observed. Similarly, monthly mean, maximum and the minimum temperature had shown an increasing trend over the past 37 years for all the districts of Karnataka. Conclusion: The more variation in rainfall during the pre-monsoon season was observed, which is more important for land preparation and other operations. The increasing trend of maximum and minimum temperature throughout the year may often cause a reduction in crop yield. It is necessary to change crops with its short duration varieties in order to avoid late season drought.

scholarly journals Simulating the Impact of Climate Change on Growth and Yield of Maize Using CERES-Maize Model under Temperate Kashmir

2019 ◽  
pp. 1-11 ◽  
Author(s):  
Bilal Ahmad Lone ◽  
Shivam Tripathi ◽  
Asma Fayaz ◽  
Purshotam Singh ◽  
Sameera Qayoom ◽  
...  
Keyword(s):  
Climate Variability ◽  
Minimum Temperature ◽  
Maize Yield ◽  
Climate Impact ◽  
Growth And Yield ◽  
Weather Data ◽  
Maximum Temperature ◽  
The Impact ◽  
Global Food ◽  
Process Based Models

Climate variability has been and continues to be, the principal source of fluctuations in global food production in countries of the developing world and is of serious concern. Process-based models use simplified functions to express the interactions between crop growth and the major environmental factors that affect crops (i.e., climate, soils and management), and many have been used in climate impact assessments. Average of 10 years weather data from 1985 to 2010, maximum temperature shows an increasing trend ranges from 18.5 to 20.5°C.This means there is an increase of 2°C within a span of 25 years. Decreasing trend was observed with respect to precipitation was observed with the same data. The magnitude of decrease was from 925 mm to 650 mm of rainfall which is almost decrease of 275 mm of rainfall in 25 years. Future climate for 2011-2090 from A1B scenario extracted from PRECIS run shows that overall maximum and minimum temperature increase by 5.39°C (±1.76) and 5.08°C (±1.37) also precipitation will decrease by 3094.72 mm to 2578.53 (±422.12) The objective of this study was to investigate the effects of climate variability and change on maize growth and yield of Srinagar Kashmir. Two enhanced levels of temperature (maximum and minimum by 2 and 4°C) and CO2 enhanced by 100 ppm & 200 ppm were used in this study with total combinations of 9 with one normal condition.  Elevation of maximum and minimum temperature by 4°C anthesis  and maturity of maize was earlier 14 days with a deviation of 18%  and  26 days with a deviation  of 20% respectively. Increase in temperature by 2 to 4°C alone or in combination with enhanced levels of CO2 by 100 and 200 ppm the growth and yield of maize was drastically declined with an reduction of about 40% in grain yield. Alone enhancement of CO2  at both the levels fails show any significant impact on maize yield.

scholarly journals Assessment of Climate Variability Trends in Nasarawa State, Nigeria

2020 ◽  
pp. 41-50
Author(s):  
Oladeinde Stephen Olufemi ◽  
Magaji I. Joshua ◽  
Ekpo Abraham Salamatu
Keyword(s):  
Climate Variability ◽  
Minimum Temperature ◽  
Global Climate ◽  
Linear Trend ◽  
Annual Rainfall ◽  
Maximum Temperature ◽  
Climate Variables ◽  
Daily Data ◽  
Annual Total ◽  
Slope Line

Changing global climate has emerged as one of the greatest environmental problems of mankind in the 21st century. However, there is still a dearth of information regarding the trends and patterns of climate variables at local and specific levels. It is against this background that this paper assessed climate variability trends in Nasarawa State, Nigeria over 21 years’ period (1997 – 2017). Daily data on climate variables for the State was obtained from the Nigerian Meteorological Agency and analysed using the linear trend function in Microsoft Excel. Pattern and course of the variables’ trend were determined using the trend/slope line and the trend equation. Out of the six investigated climatic parameters; maximum temperature, minimum temperature, total annual rainfall and dew points experienced the greatest fluctuation in Nasarawa State during the 21 years’ period (1997 – 2017). Also, while maximum and minimum temperature generally assumed an increasing trend, annual total rainfall and dew points alongside relative humidity and wind speed were generally decreasing. Policymakers in the various earth’s supporting systems such as agriculture, land and water, should employ the key findings of this study for advising some suitable adaptation and mitigation policies to cope with climate variability and change.

scholarly journals Climate Variability and Farmers’ Perception in Southern Ethiopia

2019 ◽  
Vol 2019 ◽  
pp. 1-19 ◽  
Author(s):  
Befikadu Esayas ◽  
Belay Simane ◽  
Ermias Teferi ◽  
Victor Ongoma ◽  
Nigussie Tefera
Keyword(s):  
Climate Variability ◽  
Statistical Significance ◽  
Sampling Technique ◽  
Farm Households ◽  
Maximum Temperature ◽  
Southern Ethiopia ◽  
Positive Trend ◽  
Temperature And Precipitation ◽  
Annual Minimum Temperature ◽  
Binary Logit

The study aims to analyze climate variability and farmers’ perception in Southern Ethiopia. Gridded annual temperature and precipitation data were obtained from the National Meteorological Agency (NMA) of Ethiopia for the period between 1983 and 2014. Using a multistage sampling technique, 403 farm households were surveyed to substantiate farmers’ perceptions about climate variability and change. The study applied a nonparametric Sen’s slope estimator and Mann–Kendall’s trend tests to detect the magnitude and statistical significance of climate variability and binary logit regression model to find factors influencing farm households’ perceptions about climate variability over three agroecological zones (AEZs). The trend analysis reveals that positive trends were observed in the annual maximum temperature, 0.02°C/year (p<0.01) in the lowland and 0.04°C/year (p<0.01) in the highland AEZs. The positive trend in annual minimum temperature was consistent in all AEZs and significant (p<0.01). An upward trend in the annual total rainfall (10 mm/year) (p<0.05) was recorded in the midland AEZ. Over 60% of farmers have perceived increasing temperature and decreasing rainfall in all AEZs. However, farmers’ perception about rainfall in the midland AEZ contradicts with meteorological analysis. Results from the binary logit model inform that farmers’ climate change perceptions are significantly influenced by their access to climate and market information, agroecology, education, agricultural input, and village market distance. Based on these results, it is recommended to enhance farm households’ capacity by providing timely weather and climate information along with institutional actions such as agricultural extension services.

scholarly journals Investigation of the maximum and minimum temperatures in the semi-arid region of northeastern Brazil

2011 ◽  
Vol 5 (2) ◽  
pp. 82
Author(s):  
Eunice Maia Andrade ◽  
Meilla Marielle Araújo Rodrigues ◽  
Marcos Amauri Bezerra Mendonça ◽  
Luiz Carlos Guerreiro Chaves ◽  
Rebeca Mendes Feitoza
Keyword(s):  
Minimum Temperature ◽  
Northeastern Brazil ◽  
Maximum Temperature ◽  
Data Sets ◽  
Air Temperatures ◽  
Irregular Pattern ◽  
Temperature Records ◽  
Earth’S Climate ◽  
Semi Arid Region ◽  
Semi Arid

Temperature records all over the world provide evidence that the earth’s climate is changing. To investigate changes in the extreme temperatures of semi-arid regions, we analyzed 33 years (1975-2008) of monthly maximum and minimum air temperatures for three weather stations located in Quixeramobim, Crateús and Barbalha Cities, Ceará, Brazil. The data sets were provided by INMET (Instituto Nacional de Meteorologia), Brazil. Dataset of each station was shared in decades to better understand the temperature tendency as well as to identify the warmest one. The two most recent decades were the warmest at all three stations investigated, and the highest temperature values were observed for Barbalha station. The highest increases of maximum temperature occurred during the dry season (May/Dec), and the warmest month was October, during which temperature increases of up to 1.63 °C were observed in the 1980s. The minimum temperature increased substantially during the rainy season (Jan/Apr) and during the coldest months (Jun/Jul). The highest increase of minimum temperature (3.08°C) was observed in July at the Barbalha station. The Quixeramobim station showed no significant increases in minimum temperature. The results indicate that temperature increases occur in an irregular pattern, suggesting that various regional agents affect changes in temperature.

scholarly journals Implications of spatial scale on climate change assessments

2015 ◽  
Vol 26 (1) ◽  
pp. 37-55 ◽  
Author(s):  
Santosh Pingale ◽  
Jan Adamowski ◽  
Mahesh Jat ◽  
Deepak Khare
Keyword(s):  
Climate Change ◽  
Spatial Resolution ◽  
Spatial Scales ◽  
Mitigation Strategies ◽  
Maximum Temperature ◽  
Significant Shift ◽  
Temporal Shift ◽  
Mk Test ◽  
Ajmer District ◽  
The Impact

Abstract While assessing the effects of climate change at global or regional scales, local factors responsible for climate change are generalized, which results in the averaging of effects. However, climate change assessment is required at a micro-scale to determine the severity of climate change. To ascertain the impact of spatial scales on climate change assessments, trends and shifts in annual and seasonal (monsoon and non-monsoon), rainfall and temperature (minimum, average and maximum) were determined at three different spatial resolutions in India (Ajmer city, Ajmer District and Rajasthan State). The Mann–Kendall (MK), MK test with pre-whitening of series (MK–PW), and Modified Mann–Kendall (MMK) test, along with other statistical techniques were used for the trend analysis. The Pettitt–Mann–Whitney (PMW) test was applied to detect the temporal shift in climatic parameters. The Sen’s slope and % change in rainfall and temperature were also estimated over the study period (35 years). The annual and seasonal average temperature indicates significant warming trends, when assessed at a fine spatial resolution (Ajmer city) compared to a coarser spatial resolution (Ajmer District and Rajasthan State resolutions). Increasing trend was observed in minimum, mean and maximum temperature at all spatial scales; however, trends were more pronounced at a finer spatial resolution (Ajmer city). The PMW test indicates only the significant shift in non-monsoon season rainfall, which shows an increase in rainfall after 1995 in Ajmer city. The Kurtosis and coefficient of variation also revealed significant climate change, when assessed at a finer spatial resolution (Ajmer city) compared to a coarser resolution. This shows the contribution of land use/land cover change and several other local anthropogenic activities on climate change. The results of this study can be useful for the identification of optimum climate change adaptation and mitigation strategies based on the severity of climate change at different spatial scales.

scholarly journals Future climate change scenario in hot semi-arid climate of Saurashtra, Gujarat by using statistical downscaling by LARS-WG model

MAUSAM ◽  
2021 ◽  
Vol 68 (4) ◽  
pp. 589-596
Author(s):  
JAYANTA SARKAR ◽  
J. R. CHICHOLIKAR
Keyword(s):  
Climate Change ◽  
Statistical Downscaling ◽  
Minimum Temperature ◽  
Daily Rainfall ◽  
Arid Climate ◽  
Weather Data ◽  
Maximum Temperature ◽  
Future Climate Change ◽  
Semi Arid ◽  
Far Future

Climate change is considered to be the greatest challenge faced by mankind in the twenty first century which can lead to severe impacts on different major sectors of the world such as water resources, agriculture, energy and tourism and are likely to alter trends and timing of precipitation and other weather drivers. Analyses and prediction of change in critical climatic variables like rainfall and temperature are, therefore, extremely important. Keeping this in mind, this study aims to verify the skills of LARS-WG (Long Ashton Research - Weather Generator), a statistical downscaling model, in simulating weather data in hot semi-arid climate of Saurashtra and analyze the future changes of temperature (maximum and minimum) and precipitation downscaled by LARS-WG based on IPCC SRA2 scenario generated by seven GCMs' projections for the near (2011-2030), medium (2046-2065) and far (2080-2099) future periods. Rajkot (22.3° N, 70.78° E) observatory of IMD, representing hot semi-arid climate of Saurashtra, Gujarat state was chosen for this purpose. Daily rainfall, maximum and minimum temperature data for the period of 1969-2013 have been utilized.             LARS-WG is found to show reasonably good skill in downscaling daily rainfall and excellent skill in downscaling maximum and minimum temperature. The downscaled rainfall indicated no coherent change trends among various GCMs’ projections of rainfall during near, medium and far future periods. Contrary to rainfall projections, simulations from the seven GCMs have coherent results for both the maximum and minimum temperatures. Based on the ensemble mean of seven GCMs, projected rainfall at Rajkot in monsoon season (JJAS) showed an increase in near future, i.e., 2011-2030, medium future (2046-2065) and far future (2080-2099) periods to the tune of 2, 11 and 14% respectively compared to the baseline value. Model studies indicating tropospheric warming leading to enhancement of atmospheric moisture content could be the reason for this increasing trend. Further, at the study site summer (MAM) maximum temperature is projected to increase by 0.5, 1.7 and 3.3°C during 2011-2030, 2046-2065 and 2080-2099 respectively and winter (DJF) minimum temperature is projected to increase by 0.8, 2.2 and 4.5 °C during 2011-2030, 2046-2065 and 2080-2099 respectively.  

scholarly journals Climate variability, perceptions of pastoralists and their adaptation strategies

2018 ◽  
Vol 10 (4) ◽  
pp. 596-615 ◽  
Author(s):  
Desalegn Yayeh Ayal ◽  
Maren Radeny ◽  
Solomon Desta ◽  
Getachew Gebru
Keyword(s):  
Climate Variability ◽  
Late Onset ◽  
Moisture Stress ◽  
Maximum Temperature ◽  
Southern Ethiopia ◽  
Content Type ◽  
Demographic Challenges ◽  
Baseline Information ◽  
The Impact ◽  
Livestock System

Purpose Climate variability and extremes adversely affect the livestock sector directly and indirectly by aggravating the prevalence of livestock diseases, distorting production system and the sector profitability. This paper aims to examine climate variability and its impact on livestock system and livestock disease among pastoralists in Borana, Southern Ethiopia. Design/methodology/approach Data were collected through a combination of quantitative and qualitative methods using household questionnaire, field observations, focus group discussions and key informant interviews. Areal grid dikadal rainfall and temperatures data from 1985 to 2014 were collected from national meteorological agency. The quantitative and qualitative data were analyzed and interpreted using appropriate analytical tools and procedures. Findings The result revealed that the study area is hard hit by moisture stress, due to the late onset of rainy seasons, decrease in the number of rainy days and volume of rainfall. The rainfall distribution behavior coupled with the parallel increase in minimum and maximum temperature exacerbated the impact on livestock system and livestock health. Majority of the pastoralists are found to have rightly perceived the very occurrence and manifestations of climate variability and its consequences. Pastoralists are hardly coping with the challenges of climate variability, mainly due to cultural prejudice, poor service delivery and the socio-economic and demographic challenges. Research limitations/implications Pastoralists are vulnerable to the adverse impact of climate variability and extreme events. Practical implications The finding of the study provides baseline information for practitioners, researchers and policymakers. Originality/value This paper provided detailed insights about the rainfall and temperature trend and variability for the past three decades. The finding pointed that pastoralists’ livelihood is under climate variability stress, and it has implications to food insecurity.

Sign in / Sign up

Export Citation Format

Share Document