Spatio-temporal change in rainfall over five different climatic regions of India (original) (raw)

Spatiotemporal Analysis of Rainfall Trends in Semi-Arid Regions of India Over the Last 36 Years

Springer eBooks, 2022

A quantitative and qualitative understanding of the anticipated climate-change-driven multi-scale spatio-temporal shifts in precipitation and attendant river flows is crucial to the development of water resources management approaches capable of sustaining and even improving the ecological and socioeconomic viability of rainfed agricultural regions. A set of homogeneity tests for change point detection, non-parametric trend tests, and the Sen's slope estimator were applied to long-term gridded rainfall records of 27 newly formed districts in Chhattisgarh State, India. Illustrating the impacts of climate change, an analysis of spatial variability, multitemporal (monthly, seasonal, annual) trends and inter-annual variations in rainfall over the last 115 years (1901-2015 mean 1360 mmꞏy-1) showed an overall decline in rainfall, with 1961 being a change point year (i.e., shift from rising to declining trend) for most districts in Chhattisgarh. Spatio-temporal variations in rainfall within the state of Chhattisgarh showed a coefficient of variation of 19.77%. Strong inter-annual and seasonal variability in regional rainfall were noted. These rainfall trend analyses may help predict future climate scenarios and thereby allow planning of effective and sustainable water resources management for the region.

Long Term Homogeneity, Trend and Change-Point Analysis of Rainfall in the Arid District of Ananthapuramu, Andhra Pradesh State, India

Daily rainfall data was collected for the arid district of Ananthapuramu, Andhra Pradesh state, India from 1981 to 2016 at the sub-district level and aggregated to monthly, annual and seasonal rainfall totals and the number of rainy days. The objective of this study is to evaluate the homogeneity, trend, and trend change points in the rainfall data. After quality checks and homogeneity analysis, a total of 27 rain gauge locations were considered for trend analysis. A serial correlation test was applied to all the time series to identify serially independent series. Non-Parametric Mann-Kendall test and Spearman’s rank correlation tests were applied to serially independent series. The magnitude of the trend was calculated using Sen’s slope method. For the data influenced by serial correlation, various modified versions of Mann-Kendall tests (Pre-Whitening, Trend Free Pre-Whitening, Bias Corrected Pre-Whitening and two variants of Variance Correction Approaches) were applied. A signifi...

Trends in the rainfall pattern over India

International Journal of Climatology, 2008

Monthly, seasonal and annual rainfall time series of 36 meteorological subdivisions of India were constructed using a fixed but a large network of about 1476 rain-gauge stations. These rainfall series are thus temporally as well as spatially homogenous. Trend analysis was carried out to examine the long-term trends in rainfall over different sub divisions. Also monthly contributions of each of the monsoon months to annual rainfall in each year were computed and the trend analysis was performed. It has been found that the contribution of June, July and September rainfall to annual rainfall is decreasing for few subdivisions while contribution of August rainfall is increasing in few other subdivisions.

Spatio-temporal analysis of rainfall trends in Chhattisgarh State, Central India over the last 115 years

Journal of Water and Land Development

A quantitative and qualitative understanding of the anticipated climate-change-driven multi-scale spatio-temporal shifts in precipitation and attendant river flows is crucial to the development of water resources management approaches capable of sustaining and even improving the ecological and socioeconomic viability of rain-fed agricultural regions. A set of homogeneity tests for change point detection, non-parametric trend tests, and the Sen’s slope estimator were applied to long-term gridded rainfall records of 27 newly formed districts in Chhattisgarh State, India. Illustrating the impacts of climate change, an analysis of spatial variability, multi-temporal (monthly, seasonal, annual) trends and inter-annual variations in rainfall over the last 115 years (1901–2015 mean 1360 mm·y−1) showed an overall decline in rainfall, with 1961 being a change point year (i.e., shift from rising to declining trend) for most districts in Chhattisgarh. Spatio-temporal variations in rainfall wit...

Variability and Trend Analysis of Rainfall Data of Shillong and Agartala Stations of North East India

International Journal of Environment and Climate Change

This paper discusses the variability in rainfall and trend analysis of annual and seasonal rainfall time series of Shillong and Agartala stations located in the north-east region of India. Commonly used non-parametric statistical methods namely Mann-Kendall and Sen’s slope estimator was used to analyse the seasonal and annual rainfall time series. Statistical analysis showed less variation in annual and south-west monsoon rainfall for both Shillong and Agartala stations. In the total annual rainfall, the share of south-west (SW) monsoon, north-east (NE) monsoon, winter season and summer season rainfall was observed 64.60%, 13.22%, 1.40% and 20.80%, respectively for Shillong station of Meghalaya state. However, the contribution of SW monsoon, NE monsoon, winter season and summer season rainfall in the total annual rainfall was 59.59%, 9.55%, 1.14% and 29.72%, respectively for Agartala station of Tripura state. Non-significant increasing trends of rainfall was observed by 4.54 mm/year...

Long term rainfall trend over meteorological sub divisions and districts of India

Mausam, 2017

In this paper the long term trend of annual and seasonal rainfall over different districts, Meteorological (Met.) sub-divisions and whole India have been studied using the long term rainfall data for the period from 1901 to 2013. The changes in amount and pattern of rainfall have a significant impact on agriculture, water resources management and overall economy of the country. Mann-Kendall test is applied to check the significance of the trend. Linear Regression and Theil-Sen’s non parametric test has been applied to estimate the trend. The study is carried out for 632 districts and 34 sub divisions of India by utilizing the gridded rainfall data (0.25° × 0.25°) over the main land except Andaman & Nicobar and Lakshadweep islands. Many authors have studied that extreme events are increasing but there is no trend in Pan India’s rainfall. It is observed from the annual rainfall analysis 10% of the number of districts are showing significant increasing trend and 13% significant decreasing (mainly in Uttar Pradesh) trend whereas irrespective of high and low rainfall regions, 10% area of the country is showing significant increasing trend and 8% of the area of the country showing significant decreasing trend in annual rainfall. In Meteorological Sub divisions, east & west UP are showing significant negative trend and some of the coastal sub divisions are showing positive trend. It is also observed that the country’s rainfall is not showing any trend.

Trend analysis of annual and seasonal rainfall to climate variability in North-East region of India

Global warming, climate change and its consequences are major threat for the global agriculture. The agriculture in the NorthEast region of India is supposed to more in danger due to its topographic features. Agriculture in the state of Arunachal Pradesh is dependent on rainfall and variability in rainfall due to climate change is expected to threaten the food production in future. This study examines the impact of climate change on rainfall using the trend analysis technique for the four districts of Arunachal Pradesh. For this purpose temporal trends in annual and seasonal rainfall were detected using nonparametric Mann-Kendall test at 5% significance level. The daily time series rainfall data for the period 1971-2007 were analyzed statistically for each district separately. The results of Mann Kendall test showed decreasing trend in annual mean rainfall in east Siang, upper Siang and lowers Dibang valley and no trend in the west Siang district over the period of 1971-2007. In cas...

A Study on Long Term Rainfall Pattern of Dhubri and Guwahati in Assam, India: A Time Series Approach

International Journal of Advanced Research in Computer Science

Understanding the rainfall pattern is tough for the solution of several regional environmental issues of water resources management, with implications for agriculture, climate change, and natural calamity such as floods and droughts. Statistical computing, modelling and forecasting meteorological data are the key instruments for studying these patterns. This study aims to establish the rainfall trends of the two stations of Assam viz. Guwahati and Dhubri. The collected data is secondary in nature and obtained from the website of Global Precipitation Climatology Project (GPCP) of NASA, Goddard Space Flight Centre, United States consisting of 36 years monthly rainfall records for the period 1979-2014. We have performed Sen's slope method and Mann-Kendall test to assess the magnitude along with the statistical significance of trend. So far as monthly analysis is concerned, a gradual decrease in rainfall has been observed for maximum months in both the stations. Moreover, seasonal analysis has witnessed a noticeable similarity between the stations that is the presence of significant downward trend for winter and monsoon months over the entire period of 1979-2014.