scholarly journals Seasonal and Regional Variations in Rainfall Distribution Over the Punjab-Pakistan

2020 ◽  
Vol 10 (4) ◽  
pp. 109-114
Author(s):  
Saadia Sultan Wahla ◽  
Safdar Ali Shirazi ◽  
Sohail Abbas ◽  
Mian Sabir Hussain ◽  
Mareena Khurshid
Keyword(s):  
Annual Rainfall ◽  
Positive Trend ◽  
Rainfall Distribution ◽  
Climatic Zones ◽  
Significant Positive Trend ◽  
Value Differences ◽  
South West ◽  
Southward Shift ◽  
Increasing Trend ◽  
Rainfall Variations

The purpose of present study is to investigate district and division wise annual rainfall variations over theprovince of Punjab, which is the largest in terms of population size as well important contributor in agricultural producein Pakistan. The results revealed that the rainfall trend has shifted from upper and lower Punjab towards the south,west, north and east respectively. The statistical analysis has inferred an overall increasing trend for the period 1990 to2000 and a decreasing trend during period 2001 to 2010 in Punjab province. The Z test value differences in the averagerainfall for each district level meteorological station have detected three increasing and two decreasing trends duringsummers of 1981-2015.The data revealed a significant changed seasonal trend observed in Murree and Sialkot(northern Punjab), Faisalabad and Lahore (central Punjab). Particularly, the changes have been observed in the southPunjab and over the central Punjab, while the same rainfall variations have shown a southward shift. The trend of therainfall had shifted in the Faisalabad division with the significant positive trend. In the Central Punjab, the positivetrend has also been found in all the districts. In the lower Punjab, Multan, Dera Ghazi Khan districts has shown anincreasing trend of rainfall. The findings are significant in changing agro-climatic zones in the Punjab and consequentshifting patterns of agriculture therefore can have net impact on the food security situation in the Punjab-Pakistan.

scholarly journals Seasonal and Regional Variations in Rainfall Distribution Over the Punjab-Pakistan

2020 ◽  
Vol 10 (4) ◽  
pp. 109-114
Author(s):  
Saadia Sultan Wahla ◽  
Safdar Ali Shirazi ◽  
Sohail Abbas ◽  
Mian Sabir Hussain ◽  
Mareena Khurshid
Keyword(s):  
Annual Rainfall ◽  
Positive Trend ◽  
Rainfall Distribution ◽  
Climatic Zones ◽  
Significant Positive Trend ◽  
Value Differences ◽  
South West ◽  
Southward Shift ◽  
Increasing Trend ◽  
Rainfall Variations

The purpose of present study is to investigate district and division wise annual rainfall variations over theprovince of Punjab, which is the largest in terms of population size as well important contributor in agricultural producein Pakistan. The results revealed that the rainfall trend has shifted from upper and lower Punjab towards the south,west, north and east respectively. The statistical analysis has inferred an overall increasing trend for the period 1990 to2000 and a decreasing trend during period 2001 to 2010 in Punjab province. The Z test value differences in the averagerainfall for each district level meteorological station have detected three increasing and two decreasing trends duringsummers of 1981-2015.The data revealed a significant changed seasonal trend observed in Murree and Sialkot(northern Punjab), Faisalabad and Lahore (central Punjab). Particularly, the changes have been observed in the southPunjab and over the central Punjab, while the same rainfall variations have shown a southward shift. The trend of therainfall had shifted in the Faisalabad division with the significant positive trend. In the Central Punjab, the positivetrend has also been found in all the districts. In the lower Punjab, Multan, Dera Ghazi Khan districts has shown anincreasing trend of rainfall. The findings are significant in changing agro-climatic zones in the Punjab and consequentshifting patterns of agriculture therefore can have net impact on the food security situation in the Punjab-Pakistan.

scholarly journals Trends in rainfall amount and number of rainy days in river basins of India (1951–2004)

2011 ◽  
Vol 42 (4) ◽  
pp. 290-306 ◽  
Author(s):  
Vijay Kumar ◽  
Sharad K. Jain
Keyword(s):  
Monsoon Rainfall ◽  
Statistical Significance ◽  
Kendall Test ◽  
River Basins ◽  
Rainfall Amount ◽  
Annual Rainfall ◽  
Positive Trend ◽  
Significant Positive Trend ◽  
Increasing Trend ◽  
Rainy Days

This study aims to determine trends in annual and seasonal rainfall and rainy days over different river basins across India. The data used consists of daily gridded rainfall at 1° × 1° resolution for the period 1951–2004. Sen's non-parametric estimator of slope was used to estimate the magnitude of trend whose statistical significance was assessed by the Mann–Kendall test. Among 22 basins studied, 15 showed a decreasing trend in annual rainfall; only one basin showed a significant decreasing trend at 95% confidence level. Of the 6 basins showing an increasing trend, 1 basin showed a significant positive trend. The monsoon rainfall increased over 6 basins, decreased over 16 basins and a decreasing trend for 2 basins was found statistical significant. With the exception of Ganga, Brahmaputra and EFR4, all river basins experienced the same direction of trend in monsoon and annual rainfall. Four river basins experienced increasing (non-significant) trend in annual rainy days; three basins did not show any change in annual rainy days whereas 15 basins have shown a decreasing trend in annual rainy days. The decreasing trend in three basins was statistically significant. Most of the basins have shown the same direction of trend in rainfall and rainy days at the annual and seasonal scale.

scholarly journals Tendências em índices extremos de precipitação em Cabaceiras (PB) para períodos distintos

2020 ◽  
Vol 13 (1) ◽  
pp. 271
Author(s):  
Rafaela Lisboa Costa ◽  
Heliofábio Barros Gomes ◽  
Fabrício Daniel Dos Santos Silva ◽  
Rodrigo Lins Da Rocha Júnior ◽  
Giuliene Carla Dos Santos Silva ◽  
...  
Keyword(s):  
Climate Change ◽  
Time Series ◽  
Change Detection ◽  
Annual Rainfall ◽  
Positive Trend ◽  
Total Period ◽  
Significant Positive Trend ◽  
Total Length ◽  
Expert Team ◽  
Climate Change Detection

Este trabalho teve como objetivo aplicar e estudar 11 índices de extremos de precipitação formulados pelo ETCCDI (Expert Team on Climate Change Detection and Indices, www.clivar.org/organization/etccdi), para a cidade de Cabaceiras-PB, utilizando dados diários de precipitação contínuos de 90 anos. Os índices foram calculados para o comprimento total da série, 1928 a 2017, assim como para três segmentos de 30 anos (1928-1957, 1958-1987 e 1988-2017). Os resultados evidenciaram que para muitos índices, tendências opostas e estatisticamente significativas podem ser observadas a depender do subperíodo estudado, assim como haver diferença entre estas tendências e as obtidas ao analisar-se o período total dos dados. Exemplos disso aconteceram para os índices R1mm, R10mm, R20mm, CWD e PRCPTOT.  Trends in extreme precipitation indexes in Cabaceiras (PB) for different periods A B S T R A C TThis work aimed to apply and analyze 11 precipitation extremes indexes formulated by ETCCDI (Expert Team on Climate Change Detection and Indices, www.clivar.org/organization/etccdi), for the city of Cabaceiras, located in the Borborema mesoregion and microregion of Paraíba Oriental Cariri. A municipality in the semiarid region, it has the title of municipality where it rains less in Brazil, with an annual average of just over 300mm. Daily 90-year continuous precipitation data were used for the extreme indices, with the time series analyzed for four distinct periods, the total length of the series, 1928 to 2017, as well as three 30-year segments (1928-1957, 1958- 1987 and 1988-2017). The results showed that for many indices, opposite and significant trends can be observed depending on the sub period studied, as well as differences between these trends and those obtained by analyzing the total data period. The R1, R10 and R20mm indices show significant negative trends in the 1928-1957 sub period, but positive in the following two sub periods, reflecting a significant positive trend in the total period from 1928 to 2017. Other interesting examples are CDD indices for consecutive dry days, and PRCPTOT, for total annual rainfall with rainfall greater than 1mm. The CDD showed significant positive trend only in the 1928-1957 sub period, but non-significant negative trends in the subsequent sub periods, reflecting non-significant negative trends in the total length of the series. The PRCPTOT index shows behavior opposite to the CDD index, with a significant negative trend in the 1928-1957 sub period, positive in 1958-1987 and negative again in 1988-2017, but for the total length of the series the trend is positive and significant. These results show that the analysis of extreme trends is noticeably sensitive to the sample of the analyzed period, and may not reflect the reality of the time series the longer the total length of the time series, and need to be used with caution.Keywords: climate variability, dry and wet periods, semiarid.

scholarly journals Trend and change point detection of seasonal rainfall for effective crop planning over southern transition zone of Karnataka, India

2021 ◽  
Vol 23 (3) ◽  
pp. 316-323
Author(s):  
S. SRIDHARA ◽  
PRADEEP GOPAKKALI
Keyword(s):  
Monsoon Rainfall ◽  
Negative Trend ◽  
Change Point Detection ◽  
Seasonal Rainfall ◽  
Annual Rainfall ◽  
Positive Trend ◽  
Northeast Monsoon ◽  
Significant Positive Trend ◽  
Significant Negative Trend ◽  
Northeast Monsoon Rainfall

The significance of the trends was tested by Mann-Kendall test for annual and seasonal rainfall. Among the 14 taluks, only Hassan taluk shows a significant positive trend in annual rainfall while eight taluks have shown non-significant positive trend and remaining five taluks have shown non-significant negative trend. The annual rainfall for the entire zone have shown non-significant positive trend. For the SWM season, Alur taluk shows a significant negative trend and eight taluks have shown non-significant positive trend. However, five taluks and whole zone showed a non-significant negative trend. Southwest monsoon and annual rainfall in Bhadravathi taluk was increased in 2007 (571.9 mm to 785.1 mm and 857.6 mm to 1090.9 mm, respectively) and in Shivamogga, the change in annual rainfall was decreased during 1983 (1497.5 mm to 944.0 mm) and 2011 (944.0 mm to 796.6 mm). The northeast monsoon rainfall was increased during 1992 (134.3 mm to 441.1 mm) and it was decreased during 1994 (441.1 mm to 162.0 mm) in Shikaripura taluk. Similarly, in Hunsur taluk, the SW Monsoon rainfall has increased (701.8 mm to 1010.2 mm) during 1991 and it was decreased during 2001 (1010.2 mm to 723.3 mm), in Periyapatna and Honnali taluk, Northeast monsoon rainfall has decreased during 2012 and 2011, respectively.

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

MAUSAM ◽  
2021 ◽  
Vol 68 (3) ◽  
pp. 439-450
Author(s):  
SURINDER KAUR ◽  
SUMANT KUMAR DIWAKAR ◽  
ASHOK KUMAR DAS
Keyword(s):  
Uttar Pradesh ◽  
Kendall Test ◽  
Rainfall Data ◽  
Annual Rainfall ◽  
Positive Trend ◽  
Rainfall Analysis ◽  
Increasing Trend ◽  
Long Term Trend ◽  
Agriculture Water

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.

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.

scholarly journals Occurrence of hybrid geese in Sweden—a conservation problem?

Ornis Svecica ◽  
2007 ◽  
Vol 17 (3–4) ◽  
pp. 154-186 ◽  
Author(s):  
Hakon Kampe-Persson ◽  
Henrik Lerner
Keyword(s):  
Mate Choice ◽  
Field Data ◽  
Basic Data ◽  
Positive Trend ◽  
Parent Species ◽  
Future Studies ◽  
Species Numbers ◽  
Conservation Problem ◽  
Bean Goose ◽  
Increasing Trend

This report provides basic data about hybrid geese and mixed pairs in Sweden; combinations of species, numbers, trends and origins, which can serve as a framework for future studies. Data published in national, regional and local magazines and reports as well as unpublished observations through August 2007 have been analysed. Sightings in this report were based on the observers’ suggestion of parent species. No less than 17 species were involved in the hybrid geese sighted in Sweden. Some of the combinations of species involved the red-listed species Lesser White-fronted Goose, the nominate race of Taiga Bean Goose and Red-breasted Goose. The first combinations of species appeared in Sweden already 1918–1930s, but since the last half a century, the number of hybrid geese in Sweden shows a positive trend. Several explanations to this increasing trend is proposed but not further analysed. Among all the several theories proposed for hybridisation in geese, field data from Swedish goose haunts support at least two; the ”Best-Option-Hypothesis” and ”Interspecific mate choice following false imprinting”.

scholarly journals Analyses of flood peak discharge in Cimadur river basin, Banten Province, Indonesia

2021 ◽  
Vol 331 ◽  
pp. 08006
Author(s):  
Arniza Fitri ◽  
Muhammad Shubhi Nurul Hadie ◽  
Adelia Agustina ◽  
Dian Pratiwi ◽  
Susarman ◽  
...  
Keyword(s):  
River Basin ◽  
Return Period ◽  
Daily Rainfall ◽  
Annual Rainfall ◽  
Rainfall Distribution ◽  
Flood Peak ◽  
Type Iii ◽  
Pearson Type ◽  
Catchment Areas ◽  
Peak Discharges

Cimadur river basin is one of the most important catchment areas in Lebak District, Banten Province. For the past few years, the catchment has experienced floods during the rainy season. The big issue of flooding has been recorded recently in December 2019 which has caused damage and negative impacts to the local people and surrounding community. This study aims to analyze the possibility of flood peak discharges in the catchment area of the Cimadur river. The flood discharges are calculated for 2, 5, 10, 25, 50, and 100 years return period based on the daily rainfall data from the year 2011 to 2020. The rainfall and land use data are obtained from PT Saeba Consultant. In this study, the hydrological analyses are including 1) analyses of average annual rainfall using the Thiessen method; 2) analyses of rainfall distribution and estimation of design rainfall by considering three methods involving: Log-Normal, Log Pearson Type III, and Gumbel Type 1; and 3) analyses of flood discharges by adopting Nakayasu Synthetic Hydrograph Unit (SHU). The rainfall distribution analyses show that the Log Pearson Type III provided the best fit. Based on the flood peak discharges analyses, the results show that the flood discharges for the 5, 10, 25, and 50 years return period in the Cimadur river basin are 470.71 m3/s, 560.16 m3/s, 698 m3/s, and 820.4 m3/s, respectively.

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 The Greening and Wetting of the Sahel Have Leveled off since about 1999 in Relation to SST

2020 ◽  
Vol 12 (17) ◽  
pp. 2723
Author(s):  
Tiexi Chen ◽  
Shengjie Zhou ◽  
Chuanzhuang Liang ◽  
Daniel Fiifi Tawia Hagan ◽  
Ning Zeng ◽  
...  
Keyword(s):  
Piecewise Linear ◽  
Vegetation Indices ◽  
Positive Trend ◽  
Causality Analysis ◽  
Area Index ◽  
Piecewise Linear Regression ◽  
Significant Positive Trend ◽  
Tropical Oceans ◽  
Regression Approach

The Sahel, a semi-arid climatic zone with highly seasonal and erratic rainfall, experienced severe droughts in the 1970s and 1980s. Based on remote sensing vegetation indices since early 1980, a clear greening trend is found, which can be attributed to the recovery of contemporaneous precipitation. Here, we present an analysis using long-term leaf area index (LAI), precipitation, and sea surface temperature (SST) records to investigate their trends and relationships. LAI and precipitation show a significant positive trend between 1982 and 2016, at 1.72 × 10 −3 yr −1 (p < 0.01) and 4.63 mm yr−1 (p < 0.01), respectively. However, a piecewise linear regression approach indicates that the trends in both LAI and precipitation are not continuous throughout the 35 year period. In fact, both the greening and wetting of the Sahel have been leveled off (pause of rapid growth) since about 1999. The trends of LAI and precipitation between 1982 and 1999 and 1999–2016 are 4.25 × 10 − 3 yr −1 to − 0.27 × 10 −3 yr −1, and 9.72 mm yr −1 to 2.17 mm yr −1, respectively. These declines in trends are further investigated using an SST index, which is composed of the SSTs of the Mediterranean Sea, the subtropical North Atlantic, and the global tropical oceans. Causality analysis based on information flow theory affirms this precipitation stabilization between 2003 and 2014. Our results highlight that both the greening and the wetting of the Sahel have been leveled off, a feature that was previously hidden in the apparent long-lasting greening and wetting records since the extreme low values in the 1980s.

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