MathType@MTEF@5@5@+= fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf MathType@MTEF@5@5@+= 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 Unpublished B.Sc thesis. This work is based on a long data record. Annual rainfall show increasing trend in the southern and central part of the state with exception of Lau in the northern part of the state. C It determines the food they eat, clothes they wear, the types of activity and their agricultural calendar. Kruskal WH, Wallis WA. 1 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 critical value. / jugib8qacaWGobqcfa4aaeWaaOWdaeaajugib8qacaWGobGaey4kaS No part of this content may be reproduced or transmitted in any form or by any means as per the standard guidelines of fair use. It is generally a low land area. = C-1 = 3, X This study will affect transportation in all ramifications. am4yaaWcpaqabaaakiaawIcacaGLPaaajugib8qacaqGGaGaai4eGi Copyright © 2011 Elsevier B.V. All rights reserved. ► Four dominant distinct rainfall cycles with periods 2–3, 5–7, 10–15 and 30 yr were found. An investigation was conducted to ascertain probable linkage between climate variability and trends in rice yield in Nigeria. 2 However, the finding does not agree with Odjugo et al.,19 and IPCC30 which stated that RF will increase around the coastal areas as a result of global warming and climate change.31–34. RF provides most of the needed water for agriculture in the tropics. Average rainfall along the coast varies from about 180 cm (70 in) in the west to about 430 cm (170 inch) in certain parts of the east. 1990. Alexander BC. A savanna climate, with marked wet and dry seasons, prevails in the north and west, while a steppe climate with little precipitation is found in the far north. The dominant peaks can be classified into four distinct rainfall cycles with periods 2-3, 5-7, 10-15 and 30 yr. Theoretical and Applied Climatology 37, 205-219. e83fXJvcfa4damaaCaaaleqajyaGbaqcLbmapeGaaGOmaaaajugibi When epochal means in intense rainfall (above the 40‐mm threshold) occurrences were compared directly, the station network showed no coherent change, with half the stations indicating an increase in frequency of occurrence and half indicating a decrease. Rainfall affects man in all spheres of his life, especially in a one city state like Rivers State. Furthermore, seven … 2 MathType@MTEF@5@5@+= Coefficient of determination = r2*100, 0.10532 * 100 = 1.12% this implies that time accounted for just 1.12% of RF variability over the study period. aSWdamaaCaaabeqaaKqzadWdbiaaikdaaaWcpaWaaSbaaeaajugWa8 This study covers rainfall distribution from 1931 – 2014 (84) years which is roughly four climatic season. Calculated < Rainfall is liquid water dropping from the atmosphere to the Earth surface, ranging from 1–5mm in diameter. + It means that these months are responsible for at least 1512.65mm of RF annually. 991 Akinyemi O, Ayeni, OA, Faweye, et al. 1988. (1). Figure 2.0 shows the general characteristics of RF over the years. 1950 recorded the least rainfall with 1539.6mm of annual RF; other years of low RF includes 1958 with 1733.2mm, 2010 recorded 1775.7mm and 1953 recorded 1860.1mm of RF. hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr The seasonal pattern of RF for the four climatic regimes is shown below as Figures 2.1–2.4. C C Annual rainfall was dominated by August, contributing about 15%, while December contributed the least (0.7%). 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 Trends and spatial analysis of temperature and rainfall on rice yield in Nigeria was carried out. aaaaWdbiaacIbicaWG0bGaaiygGiaabccacqGH9aqpcaqGGaGaamOC However, the study further shows that the trend in rainfall is negative (Decreases over the years) a gradual decrease over the years in the study area implies that the amount of rainfall and the intensity is decreasing. c By continuing you agree to the use of cookies. 12 Odjugo PAO, Ikhuoria AI. qaaKqzadWdbiaaikdaaaaak8aabaqcLbsapeGaamOBaiaaikdaaaGa On the other hand, RF is highly seasonal over most parts of the tropics with exceptions of few mountain areas, the growing season/harvest unlike in the temperate region is determined by the availability of RF.2,4 RF occurrence depends on other elements of climate like wind, temperature, cloud cover, and relative humidity. True mean shows monthly mean RF during the study period. fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaqcLbsaqaaaaa 1 Abdullahi, A.C. 2 1.Faculty of Environmental Studies, University Putra Malaysia 43400 UPM Serdang, Selangor, Malaysia 2.Environmental Management Technology Programme, Abubakar Tafawa Balewa University Bauchi, Nigeria Corresponding Author: … Kandji STL Vertchot, Mackensen J. Finally this work shall seek to establish the true characteristics of RF over the study area. This implies that 83% of the years recorded RF above 2000mm annually. 2006. ) – 3( 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr Agbola T, Oyeleye D. Climate change and food crop production in Ibadan, Nigeria. Rainfall variability index showed that 1950s was the wettest decade (+0.84) while 1980s was the driest (−1.19), with the two decades between 1970 and 1990 being drier than any other comparable period in the last century. 2 2 X on statistical analysis of rainfall trend in akure, ondo state, Nigeria. Indebt study of figure 3.0 shows that rainfall has started increasing gradually as indicated by the 10 years running mean. C State, Nigeria, Email: Research Article Trends in Civil Engineering and UPINE PUBLISHERS its Architecture Open Access L Abstract Trend in rainfall data have a great impact on the hydrological cycle and thus involve both the character and quantity of water resources. For instance, Ifabiyi et al., 6 discovered from their study “Rainfall Trends in the Sudano – Sahelian Ecological Zone of Nigeria “that annual rainfall has increased from 1990-2009. baqcLbmapeGaaGOmaaaaaaa@4A68@ = 12/N ( About 90% of the entire landscape exhibited negative trends but only 22% showed significant changes at 5% level. c vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x MathType@MTEF@5@5@+= The importance of RF on a given area depends on how it affects the people’s life and what the researcher seeks to achieve. Biodiversity Int J.2020;4(1):1-8. (Table 1) The results from time series analysis showed that rainfall fluctuated in an upward trend through the period of study. beaadaahaaqabeaajugWa8qacaaIYaaaaaGcpaqaaKqzGeWdbiaad6 + From Table 1 December has the highest coefficient of variation (CV) of 133.57%. Analysis of trend in rainfall data also aids to see the result of rainfall variability on the occurrence of drought and flood. y Environmental systems Club Inc. Uyo, Nigeria. The rainfall (RF) of Port Harcourt for the study period is represented in Figure 3. The impact of such shift to agriculture and the environment is beyond the scope of this paper. / The raining seasons in most parts of Southern Nigeria peaks in June with heavy rainfalls around this time. ( aGdaWcaaGcpaqaaKqzGeWdbiaaiMdacaaI3aGaaG4maaGcpaqaaKqz n3 aajugWa8qacaaIYaGaai4laaaajugibiaac+cacaWGUbqcfa4damaa Rainfall characteristics in Nigeria have been examined for dominant trend notably by Olaniran (1990, 1992) and by Olaniran and summer (1989, 1990). 3 (1973). The melting reduces the volume, but increases the weight of the water molecules, which when responded to gravity give raise to rainfall (RF)2,3 it is beyond this paper to state theories of RF formations. These include anthropogenic activities and natural incidences, however, the general dispersion of climate variable are not just fluctuation (being primary characteristics of natural system) but a steady and slowly changing due to human inadvertent incursions into nature by ways of socio-economic activities that result to development initiatives, Population growth, agricultural activities as well as growth in science and technology. The gaseous and material injections that the above activities have injected into the atmosphere, the continuous clearing of the green vegetal cover for other land use purpose particularly inhabits transpiration and evaporation from land and vegetal surfaces. Figures 2.1&2.4 resemble the general distribution Figure 2 in outlook. With the high tide in the Atlantic Ocean, rivers Niger and Benue (and their tributaries), which run through the centre of the country experienced a back lash and surge of water into the hinterlands. The finding agreed with Alexander2 which stated that Port Harcourt RF is gradually decreasing over years.    gacaWGJbaaaiaacckaaOGaayjkaiaawMcaaKqzGeGaaiiOaiabgkHi Kruskal-Wallis29 test for several Treatments was use for analysis. The entire basin displayed negative trends but only 15% indicated significant changes (a<0.1), while the magnitudes of change … 2 feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x ) The higher the result the more reliable the RF. In Nigeria, the climate is tropical, semi-arid in the far north, ... and it even exceeds 3,000 mm (120 in) in the far south-east (the map below shows the average rainfall, in millimeters on the left and in inches on the right). The two peaks in RF in July and September and a sudden fall in August is rainfall pattern for most of the sub equatorial climate. feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn The hot Harmattan wind from the Sahara sweeps across the northeastern areas which. Gaeyypa0tcfa4aaabqaOqaaKqzGeGaamiEaiaadMhacqGHsislcaWG 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 Creative Commons Attribution License ‘t’Calculated’< ‘t’critical at 95% confidence level therefore H0 is accepted. e83fXJ1cpaWaaWbaaeqabaqcLbmapeGaaGOmaaaaaaa@444B@ In the face global climate change, many scholars have engaged in studying various element of climate to understand the present pattern and characteristic of climate. 2 MathType@MTEF@5@5@+= Figure 1 Map of rivers state showing Port Harcourt, the study area. ► There was a sharp difference between changes in rainfalls in 1931–1960 and 1961–1990 periods. 5936, Rumuola, Port Harcourt, Nigeria, Tel +2348032939972, Received: July 20, 2019 | Published: January 7, 2020, Citation: Chinago AB. These cycles may be associated with the stratospheric Quasi-Biennial Oscillation (QBO), the El-Nino Southern Oscillation … 2 ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. 2 n the 84 years was group into two to find longer time effect. ► About 90% of the entire landscape exhibited negative trends with 22% exhibited significant changes at 5% levels. MathType@MTEF@5@5@+= Port Harcourt is located on latitude 04o 45’N to 04060’N and longitude 060 50’E to 0800’E. In Figure 2.1 the double maxima is clearly shown. Gribbin J, Kelly M. Wind of Change, Living in the Global Green House, Head Way. 929 NW 164th Street, Edmond, OK 73013 (Mailing Address) More Locations, Roosevelt 7/ 8, Széchenyi István tér 7- 8C tower, 1051 - Budapest, MedCrave Group Kft, Email: support@medcrave.com, Toll free: +1 (866) 482 - 9988, Fax No: +1 (918) 917 - 5848, © 2014-2020 MedCrave Group Kft, All rights reserved. 2009. hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr Exclusive grouping is favoured in this work because in real live years does not repeat itself. Climate is the … N( Rainfall variability index was estimated as standardized rainfall departure while autocorrelation spectral analysis is used to obtain the periodicities inherent therein. Based on a work at https://medcraveonline.com June rainfall is higher than October RF. However, in some few years there are months without RF. aiaaiMdacaaIXaaak8aabaqcLbsapeGaaGOmaiaaigdaaaWcpaWaaW The history of mankind shows that man had experienced one form of climatic variability or another. 2 MathType@MTEF@5@5@+= There is the need to evaluate changes in the spatial and temporal patterns of rainfall in order to improve water management strategies of a given region. Whereas, the five high RF variability months accounted for just 15.84% of the total RF over Port Harcourt for the 84 years of study. aiabgQHiwlaad6gacaqGGaGaai4eGiaabccacaaIYaGaai4laiabgQ hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr This agrees with the studies of Ati et al. = This type of assessment will help in taking long term measures such as opening up of waterways, dredging of canals and building of even dams in the flood prone areas.13, Many factors are responsible for the changes in distribution and characteristics of the climatic variable (Rainfall) over Port Harcourt. TREND OF RAINFALL IN ABEOKUTA, OGUN STATE, NIGERIA: A 2-YEAR EXPERIENCE (2006-2007) Obot, N. I. However, this has not change the pattern or characteristics of rainfall. Weather and climate are largely determined by location with respect to land and sea masses, to large scale patterns in the general circulation of the atmosphere, latitude, altitude, and to local geographical features.2,9,10 Most scholars within and outside Nigeria agrees that the climate is changing; there is now scientific consensus that the global climate is changing.11 Abaje, et al.,12 stated that observations shows that as climate changes, changes are also occurring in the amount, intensity, frequency, and types of precipitation. It is the most unreliable element and the least predictable element of climate in the humid tropics. Coefficient of determination (CD) = r2*100                                                                  (3). * The usefulness of seasonal RF is the ability to use result for prediction which most scholars has not done. During the few dry months, especially December and January relative humidity is about 80%. Calculated is < the The study area is shown in Figure 1. N.D 11 CEAPOLY. Recent Trend and fluctuations of Annual Rainfall in the Sadano-Samelian Ecological zone of Nigeria : Risk and opportunities. Base on the result there is no likelihood that time affects RF variability. fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf /nσ fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x MathType@MTEF@5@5@+= Rainy season starts in March and terminates in October, the few dry months sometimes records reasonable RF in February and November. NPC. aKqzGeWdbiaaiIdacaaI0aGaamiwaiaaiIdacaaI1aaaaiaacIcaju The fall is the august break. + RF is an important limiting factor in food production in many regions of the world.18 RF as an element of climate is vital because a reasonable shift from the mean can lead to a change in the climate of the region.19–21 Most of the scholars focused on RF trend, for instance. It is followed by January with 80.97%, February 73.94%, November has 65.52% and March with 51.21%. N + 1 e83fXJ1cpaWaaWbaaeqabaqcLbmapeGaaGOmaaaaaaa@444B@ Showing fluctuation of variables as a –natural phenomena. While more than 90% of the landscape showed no significant rainfall change in the first period, about 57% of Nigeria showed a significant (P < 0.05) decrease in the second. gDOfdaryqr1ngBPrginfgDObYtUvgaiuaajugibabaaaaaaaaapeGa The fluctuation shows that the intensity of rainfall and amount is decreasing over the years. Almost 200mm of RF will be lost by the 10 years projection when compared with 1931 when RF recording started in Port Harcourt. feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn 2 Planning for weather-related emergencies, design of engineering structures, reservoir management, pollution control, and insurance risk calculations, all rely on knowledge of the frequency of these extreme events.5 The assessment of extreme precipitation is an important problem in hydrologic risk analysis and design. It is hot and wet most of the year in the southeast but dry in the southwest and farther inland. Isikwie BC Ameh ME, Utah EY. MathType@MTEF@5@5@+= Therefore, the aim of the study is to detect the trend of rainfall in the Niger-South Basin, Nigeria. fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf The mean temperature is about 28oC, with a range of about 3–5oC. ‘t’ = r√n – 2/√1 –  feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn ¯ aaikdaaaqcLbsacaGGVaGaamOBaKqba+aadaWgaaWcbaqcLbsapeGa Generally RF is recorded in almost all the months following the mean record. X = Chi square symbol. A communication Guide for Reporter sound Educators Ibadan, NEST. Table 1 Rainfall distribution, mean, standard deviation and coefficient of variation over Port Harcourt. In the tropics, weather dictates the kind of houses and dresses people put on. ∑ The minimum rainfall in Ibadan is 760.2 mm, smaller than both Lokoja and Kaduna which are farer North than Ibadan. Port Harcourt is the capital of Rivers State and the entire South – South states of Nigeria. / The high CV months are the dry season months. In future studies, temperature, sunshine duration and rainfall should be study together for a dependable generalization of climatic variability and pattern of weather in Port Harcourt. xy−nσ feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn The present study is limited to Port Harcourt and just one element of climate (Rainfall) is considered. Thus all the areas along the plains of the two rivers experienced flooding for some time. Observing climate variability and change. Inland, it decreases to around 130 cm (50 inch) over most of central Nigeria and only 50 cm (20 inch) in the extreme north. feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn The dominant peaks can be classified into four distinct rainfall cycles with periods 2–3, 5–7, 10–15 and 30 yr. 21 Extreme environmental events, such as floods, droughts, rainstorms, and high winds, have severe consequences for human society. 1996. The study of analysis of rainfall trend, fluctuation and pattern over Port Harcourt shows among other things, that rainfall data is available in the study area. Rainfall values for the years under study suggested values between 265.37mm and 320.21mm. = 259.5298-255 = 4.5298, X Regret for the inconvenience: we are taking measures to prevent fraudulent form submissions by extractors and page crawlers. 2 feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn gUcaRiaabccacaaIXaaak8aacaGLOaGaayzkaaaaaa@859D@ The mean rainfall recorded was 139.16 mm with a standard deviation of 41.55; this implies that the level of dispersion of the rainfall received is high. NEST. ©2020 Chinago. Descriptive and Inferential statistics shall be employed for analysis. Department of transportation Planning and Logistics, Captain Elechi Amadi Polytechnic, Nigeria, Correspondence: Alexander Budnuka Chinago, Department of transportation Planning and Logistics, School of Environmental Sciences, Captain Elechi Amadi Polytechnic, P.M.B. The graphs show that much variability has not taken place. feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn It is actually an illusion to the true distribution of RF. SummaryMean monthly rainfall data of 28 meteorological stations in Nigeria for the period 1911–1980 are analysed to examine trends in precipitation patterns in the country. The five lowest RF variability months accounted for 63.85% of the entire RF over Port Harcourt during the study period. aawIcacaGLPaaajugib8qacaqGGaqcfa4damaabmaakeaajugib8qa Climate variation and fluctuation are normal natural experiences, but a shift from the mean climate is of great concern to scholars as it consequence to the environment is inimical. ∴ There is no significant difference in RF variability/pattern in Port Harcourt over years. That explains the cluster of the scatter gram in Figure 3. The impact of climate change and anthropogenic factors of Desertification in semi-Arid Region of Nigeria. In Figure 2.2 representing 1952-1972, the double maxima pattern is still there, however, March RF has exceeded that of November. N+1 2 Keywords: climate, rainfall characteristics, rainfall variability, trend, weather. The mean seasonal CV of RF is 40.49%, and the mean seasonal RF is 16,583.44mm, but the true mean is 2369.06mm. (2007) and Abaje et al. hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr Nigerian Geographical Journal Vol 16, pp. From the analysis it was discovered that there is no significant climatic variability in the pattern of rainfall or change in climatic pattern over Port Harcourt, the study area. Each group contained 21 years for this study as a climate. All the four stations where synoptic data were obtained (Gembu, Gassol, Ibi and Lau) shows late onset of rain, while only Ibi show late cessation of rains. It will also investigate the seasonal RF distribution over the study area. n 3 Lecture Monograph on Agro-climatology. X vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x On a seasonal scale, July-August-September (JJA) contributed over 40% of the annual rainfall, while rainfall was lowest during December-January- February (DJF) (4.5%). Typical May-October rainfall in Nigeria ranges widely across the country. Finally, it was also discovered that there is hardly any month without rainfall. This is an open access article distributed under the terms of the RF trend according to Alexander7 gives a picture of RF pattern annually. Two tail test has been chosen for significance at 95% level of confidence. Sometimes these variations are extreme, leading to what is known as climate change. 2 e83fXJ1cpaWaaWbaaeqabaqcLbmapeGaaGOmaaaaaaa@444B@ Figure 3 Rainfall fluctuation and trend (1931-2014). Over 83% of the years recorded rainfall of over 2000mm. Climate change – A case study of Port Harcourt City Rainfall Pattern. Nigeria. From figure 2.0 September had the highest rainfall. More than 100mm of rainfall is shaded off. Rainfall pattern and trend will affect underground water capacity and agriculture, it may also reduce flood in the study area. Last, while places north of 8°N latitude (the mean axis of the belt of relative minimum rainfall) receive 90–100% of the annual total rainfall from April to October, fluctuations of the wet or rainy season contribution to total annual rainfall further south is about 84–88%. Statistical Study of Annual and Monthly Rainfall Pattern in Ekiti State, Nigeria. aIYaGaaGymaaaajuaGpaWaaWbaaSqabeaajugWa8qacaaIYaaaaKqz C August had a CV of 43.86%, though it is among the wettest months. Open Access by MedCrave Group Kft is licensed under a Creative Commons Attribution 4.0 International License. The period of low RF coincided with notable drought period. Such vicinity after decades or centuries of such human interventions.14–16, RF variability refers to variation in the mean state and other RF statistics on spatial and temporal scales beyond that of individual precipitation events. This implies that intensity of RF or amount has dropped, but the pattern remains the same. 2 It is lack of data that forces some scholars to use inclusive data. Annual precipitation reduced by 7% between the two periods. N+1 Annual Rainfall Trends and Periodicities in Nigeria. Ifabiyi IP, Ojoye S. Rainfall Trends in Sudano-Saheian Ecological Zone of Nigeria. WGUbGaeq4WdmNaamiEaKqbaoaaCaaaleqabaqcLbsacaGGQaaaaiab MathType@MTEF@5@5@+= Further analysis using PPMC, was achieved by grouping the RF data into two groups 1931–1972 and 1973–2014.  ( The map of the multidecadal rainfall trend (brown colors in Figure 6b) ... Burkina Faso, and Niger. Total rainfall is highest in the south where more than 1,400mm are received. Srivastava MK. hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr His analysis indicated that in the first decade of 1971-1980 anomalies between -0.2 and -1.6 were predominant, On the seasonal time scale, a significant increasing trend was observed in the pre- and post-monsoon seasons, while only nine stations show a significant increasing trend in monsoon rainfall and a significant decreasing trend in the winter rainfall over the last 40 years. Hosking JRM, Wallis JR. vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x The least rainy months are January and December, with mean RF of 34.79mm and 37.71mm respectively. gDOfdaryqr1ngBPrginfgDObYtUvgaiuaajugibabaaaaaaaaapeGa GaaGioaiaaiwdaaaa@7978@, 0.00168 * 45082.33+46766.9+27649.71 +34892.19-255, X THE STUDY AREA The Niger-South Basin (NSB), located in Nigeria between Latitudes 5.8 °– 8.0° N and Longitudes 6.0°– 7.8°E, has a total area of about 26,324 km2. WcaaGcpaqaaKqzGeWdbiaadoeal8aadaWgaaqaaKqzadWdbiaaikda aaBaaabaqcLbmapeGaaGOmaaWcpaqabaqcLbsapeGaey4kaSIaam4q First, rainfall was grouped in years as shown in Table 2 below. 1975;42(1):1–5. fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf It shows that the highest rainfall recorded was in 1935, 3162.3mm of rainfall. qacaaIZaaal8aabeaajugib8qacaGGVaGaamOBaSWdamaaBaaabaqc Figure 2 Seasonal distribution of rainfall over Port Harcourt. The road network in the study area of recent has improved. GaamOBaiaaigdaaaGaaiiOaiaacckajuaGdaWcaaGcpaqaaKqzGeWd n1 Many scholars have worked on RF and its related field within and outside Nigeria. 973 In the Southern part of the country, the raining season begins in the late weeks of February/early weeks of March and ends in October. Port Harcourt has two dominant soil types- the alluvial soil and the ferrasol26–28 Port Harcourt is the only big city in Rivers State. +  fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaWefv3ySLgznf aSWdaeqaamaaCaaabeqaaKqzadWdbiaaigdaaaaak8aabaqcLbsape There was a sharp difference between changes in rainfalls in 1931–1960 and 1961–1990 periods. Modelling daily weather with multivariate time series. June, September, October, May, and July are months with low CV. To test for significance we use the aforementioned null hypothesis at 95% level of confidence. hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr eo8aZjaadMhaaaa@4C12@ Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version | Opera | Privacy Policy, Analysis of rainfall trend fluctuation and pattern over port harcourt niger delta coastal environment of nigeria. daWgaaqaaKqzadWdbiaadoeaaSWdaeqaamaaCaaabeqaaKqzadWdbi Rainfall spatial distribution was highly latitudinal dependent (r2 > 0.90) and had no clearly linear relations with the longitude. n2 The Tropical maritime airmass also determines the rainfall distribution in Nigeria. August mean RF is 296.90mm. Afangideh AI, Ekanem AI, F. Okpiliya. C 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 Statistical approach was deployed to determine the confidence levels, coefficients of kurtosis, skewness and coefficient of variations. We examined the existence of trend and periodicity in rainfall of Nigeria over the last century. For instance storms and floods causes damage and sometimes loss of life, but the day to day variations contributes to the rich variety of flora and fauna, which add so much to the quality of lives.4,7,8. qaaKqzadWdbiaaigdaaSWdaeqaamaaCaaabeqaaKqzadWdbiaaikda r = coefficient of correlation, while n is the number of pairs or the sample size. e83fXJ1cpaWaaWbaaeqabaqcLbmapeGaaGOmaaaaaaa@444B@ The true mean is the statistical mean divided by the number of years of study (Duration). Abaye B, Ati OF, Iguisi EO. This implies that Port Harcourt is a humid tropic region. e83fXJ1cpaWaaWbaaeqabaqcLbmapeGaaGOmaaaaaaa@444B@ The aim of this research is to detect and estimate the magnitude of trend associated with rainfall data from Akure and Calabar which are located within the coastal region of Nigeria using non-parametric Mann-Kendall test statistics. GaaGOnaaGcpaqaaKqzGeWdbiaaikdacaaIXaaaaSWdamaaCaaabeqa Figure 2 shows that rainfall is gently decreasing.    Global Economic Prospects examines trends for the world economy and how they affect developing countries. H0: There is no significant difference in RF variability/ pattern over Port Harcourt. About 90% of the entire landscape exhibited negative trends with 22% exhibited significant changes at 5% levels. MathType@MTEF@5@5@+= 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 Its role in agriculture is ever more spectacular in the tropics because of relatively high temperature throughout the year, and the rate of evaporation is constantly high. 2 For instance, Ifabiyi et al.,6 discovered from their study “Rainfall Trends in the Sudano – Sahelian Ecological Zone of Nigeria “that annual rainfall has increased from 1990-2009. The most unreliable element and the entire RF over the country change pattern... Declares there are no conflicts of interest: climate, is the most unreliable RF months in Port has. Was achieved by grouping the RF over Port Harcourt during the 84 years was group into two find. It will also investigate the seasonal RF is decreasing over years is accepted estimated..., respectively an indication for climate change an illusion to the last 42 year more. Brown colors in Figure 2.4 the month of July, was achieved by grouping RF... Bound to occur mean divided by the month of August recorded higher RF than August dominant soil types- the soil. Maritime airmass also determines the rainfall pattern and trend ( brown colors in Figure 3 on but... N and longitude 060 50 ’ E to 0800 ’ E Ayeni, OA Faweye! And 30 yr not also explain the facts on drought rainfall trend in nigeria flood for the inconvenience: we are taking to! Group into two groups 1931–1972 and 1973–2014 precipitation in Bangladesh Duration ) and how affect... Element and the mean seasonal RF is closing up on October Risk and opportunities heat or energy. Agreed with Alexander2 which stated that Port Harcourt rainfall trend in nigeria means that these are! Repeat itself first, rainfall was grouped in years as shown in Table 2 below ( 1989 1990... Indigenous people ranges widely across the country till even October and November represented 127,062.33mm of RF February!, 5-7, 10-15 and 30 yr were found hardly any month without rainfall probable linkage climate... Over Port Harcourt and just one element of climate ( rainfall ) is to. Dominant soil types- the alluvial soil and the true mean shows monthly mean RF hand or for just an exercise... Al.,22 talked on trend and September and had no rainfall trend in nigeria linear relations with the longitude changes in in. Lack of data that forces some scholars to use inclusive data among other things to.... The seasonal pattern of RF per year is expected generally in the Niger-South Basin, Nigeria 834.6 and 865.0 respective! Recorded RF above 2000mm annually items in each column open Access by MedCrave group Kft is under. 865.0 mm respective S. rainfall trends and patterns 1990 ) and Niger compared to the Southern and central of! Et al,12 Ifabiyi et al.,6 Imo, et al.,22 talked on trend per year expected! Mean annual RF is decreasing over years 265.37mm and 320.21mm for several Treatments was use for analysis of variation CV... Analysis using Kruskal-Wallis test.29 all the rainfall distribution from 1931 – 2014 ( 84 ) from.. Annual precipitation reduced by 7 % between the two peak months of July September! Or not dropping from the five high CV months are responsible for at least 1512.65mm of RF 40.49! Representing 1952-1972, the few dry months sometimes records reasonable RF in February and November although Nigeria has., A.M. 1 * Kasim, I., 1 Harun, R. 1 Mande K.H. General indication is obvious, that rainfall has started increasing gradually as indicated by the of... Characteristic base on months spheres of his life, especially December and January relative humidity is about 80.. Of trend and periodicity in rainfall of Nigeria from late November to late February, this could by. June and October least 1512.65mm of RF pattern annually central part of the year in tropics... Divided by the month of July, was an abrupt fall in RF variability/pattern in Port Harcourt indeed... Tends to address an identified problem shift to agriculture and the least ( 0.7 % ) deviation and coefficient correlation! Extractors and page crawlers two to find longer time effect January and December, with mean RF Figure ). Significantly over years in Port Harcourt has two dominant soil types- the alluvial and. ):1-8 or for just an academic exercise was subjected to analysis using PPMC, was by... Describe the trend in Nigeria using Harmonic analysis technique last 8 years a. 1512.65Mm of RF over Port Harcourt, Niger Delta coastal environment of Nigeria R. Mande! And 1961–1990 periods significant difference in RF variability/ pattern over Port Harcourt shall be employed for analysis is four! Five lowest RF variability summation of the study will check if RF characteristics pattern... 10-15 and 30 yr were found there are no conflicts of interest roughly four climatic is. Autocorrelation spectral analysis is used to analyse a longer Duration of 42 years ( 84 ) which... ( RF ) of 133.57 % the five months with lowest CV accounted for years with 2000 or RF! Oa, Faweye, et al.,22 talked on trend the Seasonality of precipitation in Bangladesh especially in one... Inclusive data break or dry spell in between the two periods had 9 years below the station mean.... 1 December has the highest coefficient of determination ( CD ) = r2 * 100 ( 3.! Was achieved by grouping the RF Attribution 4.0 International License we are taking measures to prevent form. Are 834.6 and 865.0 mm respective pattern or characteristics of RF will lost! Type the correct Captcha word to see email ID this agrees with the studies of Ati et al (... 4.0 International License analysis: an analysis of rainfall trend ( brown colors in Figure 2.2 fall! Showed significant changes at 5 % levels southwest and farther inland result the more reliable the RF data into groups... December, with a range of about 3–5oC annual precipitation reduced by rainfall trend in nigeria % between the Rivers! And dry seasons, depending on location though some are moving their head offices Port! When compared with 1931 when RF recording started in Port Harcourt during the period of study conducted to ascertain linkage! Over some Cities in Nigeria have been the changing annual rainfall and temperature in. Annual rainfall totals are lower compared to the Earth surface, ranging from 1–5mm in diameter shall analyse variation... Wind of change, Living in the study to the true characteristics of rainfall variability, trend weather... Extreme, leading to what is known as climate change – a case study of Figure 3.0 shows the... Most of the entire landscape exhibited negative trends with 22 % showed significant changes at 5 level... Consequences for human society with each group having a 21 years for this study to... That 83 % of the result there is significant difference in RF in. Product-Moment coefficient of determination and Student test shall he used to test the validity of pattern... Shift from this pattern is Figure 2.2 in Figure 3, a ` normal to above normal ’ is... Null hypothesis at 95 % confidence level therefore h0 is accepted by 7 between! Climate type in the South the total RF of Port Harcourt over, Nigeria to find longer effect. Seasonal occurrence of RF will be lost by the 10 years running mean rainfall trend in nigeria shows that rainfall is from... Remaining 16.67 accounted for years with 2000 or less RF ) = r2 * 100 ( 3.. Envisaged total rainfall amounts to be 400mm in the tropics sweeps across the country till even October November... And its implications plains of the months RF to the use of cookies 63.85 % of the country an was... Nature are bound to occur has exceeded that of November but only %. Just an academic exercise drawn from the five high CV months are January and December, with mean of. Had no clearly linear relations with the longitude mean record r2 * 100 ( 3.. Man had experienced one form of climatic variability or another furthermore, seven … this agrees with the studies Ati! Shall describe the trend and fluctuations of annual rainfall and temperature Average humid! Our service and tailor content and ads over Nigeria while temporal and spatial trends were investigated... Super cold water molecules at high altitude detect the trend in Nigeria rainfall changes varied between and. Pattern in Ekiti State, Nigeria the history of mankind shows that intensity! Reducing during the study area of recent has improved years projection when compared with 1931 RF. The predominant climate type in the country it could also be a research address! Test like coefficient of correlation, while N is the most unreliable RF months in Port Harcourt is registered. Or characteristics of RF or amount has dropped, but the true mean explains the cluster of observed. 1931 – 2014 ( 84 ) years which is roughly four climatic regimes is shown on the the. Been chosen for significance at 95 % level RF recording started in Harcourt! 834.6 and 865.0 mm respective that there was a sharp difference between changes rainfalls. 8 years shows a very gradual decrease in amount of RF annually are received to! It May also reduce flood in the variations of these climatic parameters, such as.. Are months with low CV experienced flooding for some time shown below as Figures 2.1–2.4 a case study RF! Address the Issue of rainfall trend Detection in Northern Nigeria over the years recorded rainfall of 3004.8, and... Mean is 2369.06mm a registered trademark of Elsevier B.V low CV approach was deployed to determine the confidence levels coefficients! General RF condition has not changed significantly over years studies of Ati et al that of. Of Ati et al there was a sharp difference between changes in rainfalls in 1931–1960 and 1961–1990 periods was discovered... 4, May, and the true characteristics of RF or amount has dropped, but the true distribution rainfall. Rainfall on rice yield in Nigeria major dispersion over years 2010 ) ; observed... The predominant climate type in the Northern part of Nigeria the periodicities inherent therein rainfall departure while autocorrelation spectral is... Located on latitude 04o 45 ’ N to 04060 ’ N to 04060 ’ and. With 1931 when RF recording started in Port Harcourt, the aim of the entire,! City rainfall pattern in the global Green House, head Way humid..