scholarly journals Analysis of weekly rainfall of different period during rainy season over Safdarjung airport of Delhi for 20th century – A study on trend, decile and decadal analysis

MAUSAM ◽  
2021 ◽  
Vol 62 (2) ◽  
pp. 197-204
Author(s):  
RAMESH CHAND ◽  
U.P. SINGH ◽  
Y.P. SINGH ◽  
P.A. KORE
Keyword(s):  
Trend Analysis ◽  
20Th Century ◽  
Rainy Season ◽  
Rainfall Data ◽  
Positive Trend ◽  
Rainfall Distribution ◽  
Coefficient Variation ◽  
Positive Tendency ◽  
Average Rainfall ◽  
Very High

The analysis of weekly rainfall and of different period during rainy season of Safdarjang airport using techniques like trend and decile have been attempted. Decadal analysis is also attempted to see any changes during the entire period. Rainy season is defined as rainfall received from week no. 23rd to 38th. Weekly rainfall data for period 1901 to 2000 is utilized for this location. As week is a shorter period to analyze rainfall for the season groups of different periods consisting of 4 weeks such as 1-4 as ‘A’, 5-8 as ‘B’ and so on up to ‘D’ is formed. For study of progressive season combination of groups such as ‘A+B’, A+B+C and ‘A+B+C+D’ are also subjected to analysis as done for weekly as well for group. The average weekly rainfall distribution indicates very high positive value of coefficient of correlation (0.94) significant at 1% level. The coefficient variation (C.V.) of weekly average rainfall shows consistency from decade 5th to 8th and 10th. Profile of average C.V. of weekly rainfall for 100 years shows consistency from week 4 to 11. Week no. 8 shows peak of rainfall. Overall decile analysis of weekly rainfall shows increasing tendency from week no. 1 to 8 for all deciles and then decreasing tendency from week no. 9 on words for all decile values. Trend analysis of group ‘C’ shows significant positive tendency with correlation as +0.20 significant at 5% level. However trend analysis of deciles of all groups shows very high C.C. around +0.95 at 1% level. Trend analysis of combination of groups shows positive trend for A+B+C and for A+B+C+D with a C.C. of 0.25 and 0.20 at 5% level. Trend of deciles for these groups also shows very high C.C. values around +0.95 at 1% level. Average, excess and deficient rainfall seen at Safdarjung airport is 5th, 7th and 4th decile with values as 594, 708 and 472 mm respectively. Analysis of two halves of century, viz., 1901-50 and 1951-2000 shows no significant trend.

scholarly journals Seasonal variability in climate time series in Rajshahi division, Bangladesh

2020 ◽  
Vol 42 (1) ◽  
pp. 1-14
Author(s):  
Md. Nezam Uddin ◽  
Syed Mustafizur Rahman ◽  
Md. Sultan-Ul- Islam ◽  
Md. Shuzon Ali ◽  
Md. Abdullah Al Mamun
Keyword(s):  
Time Series ◽  
Seasonal Variability ◽  
Rainy Season ◽  
Climate Dynamics ◽  
Rainfall Data ◽  
Wet Season ◽  
Rainfall Distribution ◽  
Average Rainfall ◽  
Climate Time Series ◽  
Recorded Temperature

This work has presented yearly dry and wet seasons in the analysis of 28 years daily recorded temperature, relative humidity and rainfall data from 1988 to 2015 in Rajshahi division, Bangladesh using Hilbert frequency analysis. Analysis has estimated the seasonal boundaries in time according to the instantaneous frequency in cycles/day and the estimations are verified with studying power spectrum of the time series. Two boundaries are obtained in each analysis over the average of yearly analysis of four years. Obtained seasonal boundaries on 16 March and 20 October are indicated as the differentiator of wet season comprises of pre-monsoon and rain in each year. Results have also shown that the length of the wet season is varying ±11days. Estimations have further justified with average rainfall distribution as shown in this work. It is even difficult to differentiate rainy season in rainfall data, however, the estimated wet season using Hilbert analysis well supported the rainy season over temperature and humidity. The presented analysis may assist further to learn more about the seasonal variability in climate dynamics.

scholarly journals ANALISIS POLA HUJAN DAN DISTRIBUSI HUJAN BERDASARKAN KETINGGIAN TEMPAT DI PULAU FLORES

2020 ◽  
Vol 5 (2) ◽  
pp. 118-128
Author(s):  
Elisabet Marlin Lesik ◽  
Hery Leo Sianturi ◽  
Apolinaris S Geru ◽  
Bernandus Bernandus
Keyword(s):  
Information System ◽  
Geographic Information System ◽  
Rainy Season ◽  
Geographic Information ◽  
Rainfall Data ◽  
Mean Values ◽  
Randomized Design ◽  
Average Rainfall ◽  
Completely Randomized Design ◽  
Rainfall Patterns

Abstrak Telah dilakukan analisis pola dan distribusi hujan berdasarkan ketinggian tempat di pulau Flores. Data rata-rata bulanan untuk mendapatkan pola curah hujan, data curah hujan harian ke dasarian untuk mendapatkan data curah hujan dan data periode curah hujan selama musim hujan. Penelitian ini menggunakan software Geographic Information System (GIS) untuk membuat peta distribusi curah hujan dan di analisis menggunakan metode Rancangan Acak Lengkap (RAL) untuk mendeteksi perbedaan nilai tengah variabel pengamatan pada elevasi yang berbeda. Berdasarkan grafik pola hujan yang ada di pulau Flores adalah pola hujan monsunal. Hasil dari perhitungan menggunakan RAL, diperoleh nilai populasi pengamatan P1 pada ketinggian tempat (0-300 m dpl) dengan curah hujan rata-rata 851,75 mm dan periode musim hujan rata-rata 10,50 dasarian. P2 pada ketinggian tempat (301-600 m dpl) memiliki curah hujan rata-rata 1367,75 mm dan periode musimhujan rata-rata 13,75 dasarian. P3 pada ketinggian tempat (601-900 m dpl) memiliki curah hujan rata-rata 1875,25 mm dan periode musim hujan rata-rata 15,75 dasarian. P4 pada ketinggian tempat (901-1200 m dpl) memiliki curah hujan rata-rata 3164,50 mm dan periode musim hujan rata-rata 22,25 dasarian. Hal ini menunjukan ketinggian tempat memiliki pengaruh terhadap curah hujan dan periode musim hujan di pulau Flores.Kata Kunci: Pola hujan; curah hujan; periode musim hujan; Geographic Information System (GIS); Rancangan Acak Lengkap (RAL). Abstract An analysis of rainfall patterns and distribution based on altitude on the island of Flores has been done. Monthly average data to get rainfall patterns, daily to basic rainfall data to get rainfall data, and rainfall period data during the rainy season. This study used Geographic Information System (GIS) software to create rainfall distribution maps and is analyzed using the Completely Randomized Design (CRD) method to detect differences in mean values of observational variables at different elevations. Based on a chart of rain patterns on Flores island is a monsoonal rain pattern. The results of calculations using RAL, observational population obtained values P1 at altitude (0-300 m asl) with an average rainfall of 851.75 mm and an average rainy season period of 10.50 dasarian. P2 at altitude (301-600 m asl) has an average rainfall of 1367.75 mm and an average rainy season period of 13.75 dasarian. P3 at altitude (601-900 m above sea level) has an average rainfall of 1875.25 mm and an average rainy season period of 15.75 dasarian. P4 at altitude (901-1200 m asl) has an average rainfall of 3164.50 mm and an average rainy season period of 22.25 dasarian. This shows that altitude has an influence on rainfall and the rainy season period on Flores Island. Keywords: Rain patterns; rainfall, periods of the rainy season; Geographic Information System (GIS); Completely Randomized Design (CRD).

scholarly journals 50 year rainfall data analysis and future trend in Saharanpur region

MAUSAM ◽  
2021 ◽  
Vol 63 (1) ◽  
pp. 55-64
Author(s):  
VARTIKA SINGH ◽  
PRAMENDRA DEV
Keyword(s):  
Ground Water ◽  
Rainwater Harvesting ◽  
Water Reservoir ◽  
Negative Trend ◽  
Rainfall Data ◽  
Annual Rainfall ◽  
Positive Trend ◽  
Environmental Implications ◽  
Annual Average ◽  
Average Rainfall

The environmental implications of rainfall pattern in replenishment of ground water system of Saharanpur region, located in western Uttar Pradesh, have been discussed. The mathematical analysis of rainfall dissimilarity of Saharanpur region for a period of 50 year (1959 to 2008) display a quite good range from 497.70 to 4357.5 mm with an annual average rainfall value of 1209.8 mm. The positive trend of departure from the computer value of average annual rainfall exhibits appropriate periods for recharge of ground water reservoir. The recorded data of annual rainfall during the last 3 year reveal values below the calculated annual average rainfall, pointing out negative trend. The statistical analysis of rainfall data involves computations of various statistical parameters, which also support the negative trend of rainfall. The prediction of expected future rainfall trend for a period up to 2018 has been made, which indicates a negative trend. The proposal have been incorporated to implement a plan for augmentation of ground water resource and also to develop possibilities of rainwater harvesting.

scholarly journals Statistical Assessment of Rainfall Characteristics in Upper Blue Nile Basin over the Period from 1953 to 2014

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 468 ◽  
Author(s):  
Abeer Samy ◽  
Mona G. Ibrahim ◽  
Wael Elham Mahmod ◽  
Manabu Fujii ◽  
Amr Eltawil ◽  
...  
Keyword(s):  
Trend Analysis ◽  
Rainy Season ◽  
Prediction Models ◽  
Annual Rainfall ◽  
Nile Basin ◽  
Rainfall Distribution ◽  
Blue Nile ◽  
Blue Nile Basin ◽  
Increasing Trend ◽  
Upper Blue Nile Basin

Investigating the trends of hydro-meteorological variables and checking its variability are of great importance for water resources management and development in the River Nile basin. The present study aimed to analyze the rainfall variability and trends in the Upper Blue Nile Basin (UBNB) over a period from 1953 to 2014. Variability analysis showed that the basin has been suffering from variable rainfall events causing severe droughts and floods over different years. According to precipitation concentration index calculations, the basin had irregular and strong irregular rainfall distribution over the annual and dry seasons, while the basin had a uniform and moderate rainfall distribution during the rainy season and small rainy season. For the total annual rainfall, Mann–Kendall test indicated that, for the eastern central part of the basin, a significant increasing trend of 12.85 mm/year occurred over the studied period, while, for the southwestern part of the basin, a significant decrease of 17.78 mm/year occurred. For the rainy season, a significant increasing trend over the northeastern and eastern central parts of the basin with the magnitude of 3.330–12.625 mm/year occurred. Trend analysis was applied on the monthly averaged rainfall over the whole basin and revealed that July and August are the most contributors of rainfall to the basin with 23.32% and 22.65%. Changing point assessment revealed that at Lake Tana outlet there is a decreasing of the rainfall of 17.7% after 1977 that matched with the trend analysis results. The data and results contained herein provide updated information about the current situation in the UBNB. The results can be used to predict future precipitation and estimate the uncertainty in future precipitation prediction models.

THE BIOENERGY CROPS MARKET IN UKRAINE: TRENDS OF DEVELOPMENT AND SPATIAL DIFFERENTIATION

2017 ◽  
Author(s):  
Yuriy Hayda ◽  
◽  
Khrystyna Firman ◽  
Keyword(s):  
Sugar Beet ◽  
Agricultural Sector ◽  
Spatial Differentiation ◽  
Raw Material ◽  
Biofuel Production ◽  
Bioenergy Crops ◽  
Positive Trend ◽  
Energy Potential ◽  
Resource Base ◽  
Positive Tendency

In this article analyzes the development of trends of bioenergy crops market development in Ukraine and its current state are analysed. The possibility and feasibility of synergy of mutual development of bioenergy crops market and bio-oil market in Ukraine were noted. The necessity of state support and stimulation of bioenergy crops and different types of biofuels production in Ukraine was stated. A positive trend of growth of planted areas and production of rapeseed in Ukraine was revealed. During the study period (2013-2019) the production of rapeseed was increased by 1.4 times. The greatest energy potential for the production of bioethanol is in the sugar beet subcomplex of the agricultural sector. Over the past few years, the production of sugar beet was at its highest in 2014 (15.7 million tonnes), while the following years saw a decrease in cultivated areas of sugar beet and, consequently, a drop in its gross output - to 8.3 million tonnes in 2020. Significant resource potential for the production of bioethanol also have cereal crops (wheat, rye, barley, maize), the area under which during the last ten years remains relatively stable (14.4-15.3 million ha). Among grain crops the most effective raw material for the production of bioethanol is maize. A positive tendency of biennial growth of planted area under this crop is revealed. The space differentiation of resource base of bioenergy in Ukraine is prominent. The cluster analysis revealed three groups of areas based on the similarity of the energy resources for bioenergy purposes. Two clusters including Khmelnytskyi, Ternopil, Zhytomyr and Chernihiv, Vinnytsia, Cherkasy, Sumy, Kirovograd, Poltava and Kyiv regions should be considered as the most promising areas for concentration of capacities in biofuel production. It is noted that the trajectory of development bioenergetic sector of the country is always conditioned by compromise between compliance with optimal levels of its energy and food security.

scholarly journals Inter-annual and seasonal trends of vegetation condition in the Upper Blue Nile (Abay) Basin: dual-scale time series analysis

2015 ◽  
Vol 6 (2) ◽  
pp. 617-636 ◽  
Author(s):  
E. Teferi ◽  
S. Uhlenbrook ◽  
W. Bewket
Keyword(s):  
Trend Analysis ◽  
Sustainable Land Use ◽  
Integrated Analysis ◽  
Positive Trend ◽  
Blue Nile ◽  
Seasonal Trends ◽  
Modis Ndvi ◽  
Vegetation Condition ◽  
Gimms Ndvi

Abstract. A long-term decline in ecosystem functioning and productivity, often called land degradation, is a serious environmental challenge to Ethiopia that needs to be understood so as to develop sustainable land use strategies. This study examines inter-annual and seasonal trends of vegetation cover in the Upper Blue Nile (UBN) or Abbay Basin. The Advanced Very High Resolution Radiometer (AVHRR)-based Global Inventory, Monitoring, and Modeling Studies (GIMMS) normalized difference vegetation index (NDVI) was used for long-term vegetation trend analysis at low spatial resolution. Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data (MOD13Q1) were used for medium-scale vegetation trend analysis. Harmonic analyses and non-parametric trend tests were applied to both GIMMS NDVI (1981–2006) and MODIS NDVI (2001–2011) data sets. Based on a robust trend estimator (Theil–Sen slope), most parts of the UBN (~ 77 %) showed a positive trend in monthly GIMMS NDVI, with a mean rate of 0.0015 NDVI units (3.77 % yr−1), out of which 41.15 % of the basin depicted significant increases (p < 0.05), with a mean rate of 0.0023 NDVI units (5.59 % yr−1) during the period. However, the MODIS-based vegetation trend analysis revealed that about 36 % of the UBN showed a significant decreasing trend (p < 0.05) over the period 2001–2011 at an average rate of 0.0768 NDVI yr−1. This indicates that the greening trend of the vegetation condition was followed by decreasing trend since the mid-2000s in the basin, which requires the attention of land users and decision makers. Seasonal trend analysis was found to be very useful to identify changes in vegetation condition that could be masked if only inter-annual vegetation trend analysis was performed. Over half (60 %) of the Abay Basin was found to exhibit significant trends in seasonality over the 25-year period (1982–2006). About 17 and 16 % of the significant trends consisted of areas experiencing a uniform increase in NDVI throughout the year and extended growing season, respectively. These areas were found primarily in shrubland and woodland regions. The study demonstrated that integrated analysis of inter-annual and intra-annual trends based on GIMMS and MODIS enables a more robust identification of changes in vegetation condition.

scholarly journals THE INFLUENCE OF THE BRAZILIAN CERRADO DEFORESTATION IN GRAIN CULTURE AND ITS CONSEQUENCES TO LOSSES THE SOIL IN THE CACHOEIRA DOURADA RESERVOIR REGION – CENTRAL - WESTERN BRAZIL

2013 ◽  
pp. 01
Author(s):  
João Batista Pereira Cabral ◽  
Valter Antonio Becegato ◽  
Francismário Ferreira dos Santos
Keyword(s):  
Annual Cycle ◽  
Annual Rainfall ◽  
Brazilian Cerrado ◽  
Rainfall Distribution ◽  
Rainfall Variation ◽  
Influence Area ◽  
Average Annual Rainfall ◽  
Average Rainfall ◽  
Soil Preparation ◽  
Erosivity Index

The erosivity index (EI30) and its spatialization were determined for the contribution basins of the Cachoeira Dourada hydroelectric system reservoir, located between the states of Goiás and Minas Gerais and limited by coordinates 640000-760000 m W and 7910000-7975000 m N. Average monthly and annual rainfall data corresponding to eight localities and to a 30-year period were treated. It was observed that in this period the average annual rainfall was 1441 mm, the highest and lowest indexes having occurred respectively in January and July (7.5 mm). EI30 varied from 7100 to 8500 MJ mm (ha h)-1. The most representative period was October to March, corresponding to 7880.3 MJ mm (ha h)-1and 94% of the average annual EI30. The average rainfall variation coefficient for all stations was 82.73%. There is an irregular rainfall distribution in the region and consequently a non-uniform spatialization of the erosivity indexes within the influence area of the reservoir. The highest rainfall values coincide with the period of soil preparation and development of annual-cycle plants, mainly soybean and corn.

scholarly journals Rainfall trend and variability over Opak River basin, Yogyakarta, Indonesia

2020 ◽  
Vol 1000 (1000) ◽  
Author(s):  
Wakhidatik Nurfaida ◽  
Hendra Ramdhani ◽  
Takenori Shimozono ◽  
Indri Triawati ◽  
Muhammad Sulaiman
Keyword(s):  
River Basin ◽  
Water Resource ◽  
Rainfall Intensity ◽  
Kendall Test ◽  
Rainfall Data ◽  
Positive Trend ◽  
Sen’S Slope Estimator ◽  
Sen’S Slope ◽  
Slope Estimator

Rainfall intensity seems to be increasing nowadays due to climate change as presented in many studies of both global and regional scale. Consequently, cities worldwide are now more vulnerable to flooding. In Indonesia, increasing frequency of floods was reported for the past decades by The National Agency for Disaster Countermeasure (BNPB). To understand the rainfall changes, long-term trend evaluation over a specific area is then crucial due to the large variability of spatial and temporal rainfall distribution. This study investigates the homogeneity and trend of rainfall data from 20 stations over the Opak River basin, Yogyakarta, Indonesia. A long-term ground observation rainfall data whose period varies from 1979 to 2019 were analyzed. Non-parametric Mann – Kendall test was applied to assess the trend, while the magnitude was calculated using the Sen’s slope estimator. An increasing annual maximum of daily rainfall intensity was observed at four stations on a 0.95 confidence level based on the Mann – Kendall test, while the Sen’s slope estimator shows a positive trend at almost all stations. The trend of heavy rainfall frequency was also found to be significantly increased, with only one station showed a decreasing trend. Furthermore, this paper also described the spatial and temporal rainfall variability. Positive trend was mostly found during the rainy season, while the negative trend occurred during the dry season. This could pose a challenge for water resource management engineering and design, such as water supply systems or reservoir management. Understanding this phenomena will benefit hydrologists in preparing future water resource engineering and management.

scholarly journals Monitoring and mapping of seasonal vegetation trend in Tamil Nadu using NDVI and NDWI imagery

2019 ◽  
Vol 11 (1) ◽  
pp. 54-61 ◽  
Author(s):  
P.J. Prajesh ◽  
Balaji Kannan ◽  
S. Pazhanivelan ◽  
K.P. Ragunath
Keyword(s):  
Trend Analysis ◽  
Tamil Nadu ◽  
Vegetation Index ◽  
Regional Scale ◽  
Negative Trend ◽  
Positive Trend ◽  
Vegetation Growth ◽  
Kharif Season ◽  
Regression Slope ◽  
Land Covers

In order to monitor vegetation growth and development over the districts and land covers of Tamil Nadu, India during the crop growing season viz., Khairf and Rabi of 2017, Moderate Resolution Imaging Spectroradiometer (MODIS) derived surface reflectance product (MOD09A1) which is available at 500 m resolution and 8-day temporal period was used to derive a time series based Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) for monitoring and mapping terrestrial vegetation trend analysis which showed areas in Tamil Nadu having vegetation greening and vegetation browning. The regression slope values derived from the trend analysis was utilized and the NDVI and NDWI seasonal trend showed majority of area in Tamil Nadu falling under positive trend during the Kharif season (86.52 per cent for NDVI and 90.29 per cent for NDWI). While irrespective of land cover classes, NDVI and NDWI during Kharif season showed a greater positive trend (greening) with least negative trend (browning) for vegetation growth over the land covers whereas during Rabi season it was observed to have a mix of positive trend and negative trend over the land covers. This study was carried out to show that a systematic study can be done for understanding changes over the landscape through the use of high spatial resolution satellite dataset such as MODIS, which provides detailed spatial and temporal description at regional scale. While a trend analysis using regression slope values can be considered for demonstrating the spatial and temporal consistency on land and vegetation dynamics.

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