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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]

• 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]

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]