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The climatic variability changes in the world impact the growth of cash crops and India is no exception. In this research work, Mann-Kendall and Sen's slope estimator have been used to study the possible existence of trend in the production of tea and its price for Guwahati, Kolkata, North-India, South India and India as a whole. The analysis reveals blunt increasing trend in annual data set (2011-2022), but mixed for month wise analysis. [ABSTRACT FROM AUTHOR]

Analysis of rainfall distribution and its changing pattern plays a vital role in managing water resources in a region. This work examined the spatio-temporal variability and trend of rainfall on yearly and season-wise scales during 1971–2013 in the Wainganga river basin situated in middle India. The Mann–Kendall (MK) test was implemented for identifying the temporal variation in rainfall trends. The magnitude of this changing trend was estimated by applying Sen's slope (SS) method. A paired sample t-test was also employed to appraise the statistical significance of changes in rainfall data. The results of MK and SS tests show both upward and downward trends. The results show positive and negative trends in the south-eastern and northwestern parts of the study area for annual rainfall. The monsoon rainfall also shows very close proximity with annual rainfall data trends. The t-test states that the observed changes in precipitation are statistically significant. After trend and pattern analysis, state-space models (SSMs) were used to predict rainfall for future scenarios. Four SSMs (single, double, and triple exponential, autoregressive integrated moving average (ARIMA)) were employed for rainfall prediction. The analysis shows that the ARIMA is best for rainfall prediction with architecture of (0,0,0) (2,1,0) and can be used in Wainganga River basin. [ABSTRACT FROM AUTHOR]

Three timescale i.e. monthly, seasonal and annual rainfall data of Bundelkhand region, Central India, was analyzed for 40 years (1981-2020). The annual mean average rainfall for the region ranges between 657.7 mm and 1146.4 mm for the studied period with the month August receiving the highest amount of rainfall. The region receives about 90 % of its annual rainfall during South West Monsoon period i.e. from June to September. Temporal trend of rainfall for different timescale was analysed using nonparametric Mann-Kendall test and Sen's slope estimator. Increasing and decreasing trend were found for the three timescale in which the study was carried out. Annual rainfall trend of Bundelkhand region is found to follow decreasing trend except for Sagar district. A decreasing South West Monsoon rainfall trend was also observed in 11 districts of Bundelkhand region. [ABSTRACT FROM AUTHOR]

Climate inconsistency, particularly that of the annual rainfall and air temperature, has gained a great deal of attention worldwide. The magnitude of the changeability or fluctuations of the components changes according to areas. Consequently, analyzing the spatiotemporal dynamics of meteorological factors within the setting of changing climate, particularly in nations where rainfed horticulture is largest, is imperative to assess climate-induced changes and propose possible adjustment methodologies. To that end, the display consider looks at long-term changes and short-term variances in monsoonal precipitation and temperature over Dahod area of Gujarat state, India. Rainfall and temperature data for the period 1981 to 2017 were analysed in this study. To analyse and examine the problem, statistical trend analysis techniques Mann-Kendall test and Sen's slope estimator were used. Sen's slope is calculated with 95% confidence interval for seasonal rainfall that in months June to September, maximum and minimum temperature. [ABSTRACT FROM AUTHOR]

Investigating the temporal dynamics of rainfall in a changing climate, especially in rainfed agriculture regions, is crucial for analyzing climate-induced changes and offering adaptation options. Since Mizoram experiences unfavorable impacts of rain nearly every year, the region rainfall has been altering over the years, and vital climatic activity is becoming uncontrollable. The current study is primarily concerned with the changing trend of rainfall over Mizoram, which includes both short-term persistence (STP) and long-term persistence (LTP) of rainfall in seasonal and annual time series of rainfall overseeing for the period of 25 years of daily average rainfall from 1996 to 2020 collected collectively from the seven stations over the study area of Mizoram. Four different Mann-Kendall method iterations were used to analyze rainfall trends: the original or conventional method (without autocorrelation) (MnKn1), removing lag-1 autocorrelation (trend-free pre-whitening), considering multiple lag autocorrelation (more than lag-1 autocorrelation) (MnKn3), and Hurst coefficient or LTP (MnKn4). In the analysis, the study found that during monsoon, station Lawngtlai (LT) observed the highest rainfall having a Z value of 1.986, increased by 0.466 cm/year, while station Serchhip (SC) observed the lowest rainfall having Z value of -2.282, decreased by -0.163 cm/year. After applying modified MnKn4, we observed LTP of rainfall in winter at station Lawngtlai (LT) with an increasing trend and other stations observing STP in almost all seasons either increasing or decreasing trend. Therefore, possible climate change adaptation measures should be made to optimize rainfall use for various applications for the states of Mizoram., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Characterization of nonlinear trends in time series of hydroclimatic variables exhibiting nonstationarity is necessary for more realistic projections of climate change and for optimal design of hydraulic structures. The present study was conducted to demonstrate the applicability of a novel Monte-Carlo-based singular spectrum analysis (SSA) to characterize nonlinear trends in historical time series of rainfall characteristics. Long-term (1960–2015) rainfall records for 17 gauges located in the Malaprabha River Basin, India, were used to analyze spatiotemporal variabilities of trends in rainfall totals and number of rainy days for annual and seasonal time periods. While the traditional Sen's Slope and Mann–Kendall (MK) trend tests indicated statistically nonsignificant decreasing monotonic trends at most gauge stations, SSA revealed the existence of steep nonlinear trends and distinct change points in the direction of the trend over the period of record for both rainfall and rainy days. Results of this study demonstrate the potential for SSA to extract crucial information on the trajectories of nonlinear trends and change points in time series of hydroclimatic variables that exhibit nonstationarity. [ABSTRACT FROM AUTHOR]

The contradictory approaches to water sharing at regional and global scale has detrimental impacts on human (domestic and agricultural) and ecological demands. Economic activities have also been affected, including where livelihoods and survival depends upon agriculture. This study considers past and future flow trends and water availability in the Jhelum basin, focusing on the Neelum River. The Neelum River is largest tributary of Jhelum basin and is also an important transboundary river shared between Pakistan and India. To detect historical trends of flow data, Man Kendall and Sen's slope trend analysis were carried out, whereas the future projections in the flow regime were estimated using First Order Morkove stationary method. The analysis shows significant flow depreciation in the period between 1991 and 2013. The two stations were considered in this study Nusheri (Upstream) and Muzaffarabad (Downstream). At Nusheri station monthly and annual decreasing trends dominated (significant decline in the months of June, July and August) including the annual average declining rate of 3.386 cumecs per year. At Muzaffarabad station (downstream to Nusheri) the similar decreasing trends were dominated as were at the upstream, the overall annual average decline rate was 3.186 Cumecs per year The overall flow depreciation was estimated about14% by volume at both stations in the period of 1991 to 2013. The Pakistan has built Neelum-Jhelum hydropower and India has built Kishan Ganga hydropower project on the same river, therefore fair allocation of flow without curtailing water must be made to ensure water availability throughout the year in this river. This will also help to reduce long withstanding turbulence of Pak-India relations. [ABSTRACT FROM AUTHOR]

Trend analysis of streamflow and its linkages to rainfall can facilitate the development of water resource management plans for watersheds. The present study focuses on trends in observed streamflow of the lower Tamiraparani river sub-basin in Tamilnadu, India using Mann - Kendall test and Sen's slope estimator for a period of 30 years. From this analysis, both the annual streamflow, annual rainfall increased very marginally at the rate of 0.1799 m3/s/year and 4.3741 mm/year, respectively. Similarly, in the northeast monsoon period, both the rainfall and streamflow were increased very minimally during the analysis period. However, the observations made during the southwest monsoon showed declining trends for most of the rainfall stations and no significant trend was observed for streamflow. The calculated Spearman's Rho correlation factor (p) between rainfall and streamflow showed weak correlation during summer (0.26) and very strong correlation during northeast monsoon (0.83), strong correlation during southwest monsoon (0.53) and moderate correlation during winter (0.40). From this analysis, using Mann - Kendal test and Spearman's correlation it implies that other than precipitation and temperature, urbanization, watershed and ecological development of the catchment area could have also influenced the trends of streamflow. [ABSTRACT FROM AUTHOR]

• The temperature is rising in lower troposphere and declining in lower stratosphere. • Water vapor has increasing trend in lower part of troposphere. • O 3 is rising in lower/lower-mid troposphere, while declining in lower stratosphere. • Total column integrated methane has a significant increasing trend. • Total carbon-monoxide has not shown any significant trend. The present work has been carried to analyze the changes in trend of temperature, water vapor and ozone profiles at different atmospheric layers, total column integrated methane (TCH4) and total column integrated carbon-monoxide (TCO) over the Indian region. The atmospheric column was divided into few atmospheric layers: surface-850 hPa, 850–500 hPa, 500–100 hPa, 100–50 hPa and 50–1 hPa. Monthly averages of these parameters were calculated from AIRS Level 2 Standard Products for a decade from 2003 to 2012. A non-parametric statistical test with seasonal modification was applied to check the trends of various parameters. Monthly means were used to examine the seasonal dependency in the trend, and allowing more information from the data to be used. The layer average temperature in surface-850 hPa layer has shown significant increase in overall annual trend over eastern part, southern part and averaged over whole India with an increase of 0.041 K/year, 0.034 K/year and 0.034 K/year, respectively. The overall trend was decreasing over all but southern parts in 100–50 hPa layer at the rate of 0.079 K/year over whole India. For water vapor trends, it has been found that layer integrated water vapor (LIWV) in surface-850 hPa layer has significant overall increasing trend over western part, southern part and averaged over whole India with the rate of increase of 0.555%/year, 0.598%/year and 0.486%/year respectively. For LIWV (850–500 hPa), only western part has significant increasing trend at a rate of 0.879%/year. However, LIWV in 500–100 hPa layer does not show any significant trend. Total water vapor (TWV) has shown significant annual increasing trend over all the parts except over the central part. The increasing trend has been estimated as 0.962%/year over whole India. The layer integrated ozone (LIOZ) in surface-850 hPa has significant increasing trend over western part (0.062%/year) and southern part (0.071%/year). In 500–100 hPa layer, the LIOZ has statistically significant decreasing trend over whole India at a rate of 0.112%/year. For LIOZ averaged over whole India in 100–50 hPa, there is significant decreasing trend with a rate of 0.273%/year. Overall, the ozone concentration is increasing near surface, whereas it is decreasing in lower stratosphere. The total column ozone (TOZ) has not shown any significant trend. The column integrated methane has shown an increasing trend (0.366%/year) over all parts of the country, whereas, TCO has not shown any significant trend. [ABSTRACT FROM AUTHOR]

While determining the quality of water for any water body, low, medium and high values of a parameter stand out to be a very important reference. Moreover, these values are used to decide various design parameters based on scientific aspects and its real applications around the world. In this research, determination of trend of water quality (WQ) status for Bhagirathi River was carried out at two sites, Uttarkashi and Tehri station (Tehri Zero point), for 18 WQ parameters and discharges. Preliminary analysis reveals that all parameter concentrations are below the standard permissible limit. No significant correlation was observed between any parameter with respect to discharge; however, out of 18 parameters, 14 were showing negative correlation indicating groundwater source and geological origin. Moreover, a strong correlation was found between 11 parameters at both sites. Seasonal Mann-Kendall test and Sen's slope method have been used to detect trend and to quantify its magnitude. Increasing trend in the concentration of 7 WQ parameters (Q, EC, K+, Na+, SO4 2-, BOD and Na%) was observed while decreasing trend was observed for 8 parameters (TA, Ca2+, HCO3 -, Mg2+, NO2 + NO3, o-PO4 3-, DO and TH). Overall, WQ of Bhagirathi River was found to be good and hence is suitable for drinking and life-supporting activities. [ABSTRACT FROM AUTHOR]

In the present study, trends and variations in climatic variables (i.e. rainfall, wet day frequency, surface temperature, diurnal temperature, cloud cover, and reference and potential evapotranspiration) were analyzed on seasonal (monsoon and non-monsoon) and annual time scales for the Ajmer District of Rajasthan, India. This was done using non-parametric statistical techniques, i.e. the Mann-Kendall (MK) and Modified Mann-Kendall (MMK) tests, over a period of 100 years. The MK test with prewhitening (MK-PW) of climatic series was also applied to climatic variables and the results were compared to those obtained through the MK and MMK tests in order to assess the performance of trend detection methods. The Pettitt-Mann-Whitney (PMW) test was applied to detect the temporal shift in climatic series. The trend analysis revealed that annual and seasonal rainfall did not show any statistically significant trend at a 10% significant level. A noticeable trend increase was found in wet day frequency, surface temperature and reference evapotranspiration ( ET) during the non-monsoon season from the three non-parametric statistical tests at a 10% significance level. A statistically significant decrease in maximum temperature was found during the non-monsoon season by the MK-PW test alone. This analysis of several climatic variables at the district scale is helpful for the planning and management of water resources and the development of adaptation strategies in adverse climatic conditions. [ABSTRACT FROM AUTHOR]

An increase in the human population, urbanization, industrialization, infrastructural development, and current agricultural practices acts as major factors leading to the decline of the groundwater table in the region. The present study analyzes the noticeable effect of anthropogenic pressure on the groundwater table in the Bist-Doab region in Punjab, India, from 1996 to 2016. Statistical techniques, viz., Mann-Kendall Z statistics and Sen's slope, were used to estimate the water table decline in the area. The results indicate that there was a slight increase in the groundwater table in the Kandi belt of Siwalik foothills and south-western parts of the region. In the rest of the areas, a significant declining trend was observed in the groundwater table. The decline in the water table ranged from 56 to 149 cm per year in the pre- and post-monsoon seasons due to increasing in rice cultivated area, which is an alarming situation in the aquifer system of the region. Hence, to reduce the further decline of the groundwater table, water management practices need to be encouraged in the region. There is requiring immediate attention to change the present land-use/cover practices and to grow less water-consuming crops instead of high water-consuming crops to reduce the pressure on groundwater. [ABSTRACT FROM AUTHOR]