Impact of Climate Change on Rainfall Distribution on Cassava Yield in Coastal and Upland Areas of Akwa Ibom State, Nigeria

This study examined the implication of rainfall variability on cassava yield in selected coastal and upland areas of Akwa Ibom State, Nigeria. Thirty years daily rainfall data were collected from Nigeria Meteorological Agency (1989 – 2018); cassava yield data were also collected from Akwa Ibom State Ministry of Agriculture Uyo (1989 – 2018). Descriptive statistics was used to determine the average annual rainfall and cassava yield. Time series analysis were used to assess the relationship between rainfall and cassava yield. The result indicated an increase in rainfall trends in all areas with Eket – r2 = 0.6631, Oron - r2 = 0.5329, Uyo - r2 = 0.4215 and Ikot Ekpene - r2 = 0.4042. The result also showed an increase in yield of cassava in Uyo and Ikot Ekpene at r2 = 0.2436 and 0.4397 respectively; while its decreases in Eket and Oron at r2 = 0.0611 and 0.1159 respectively. This suggested that a high yield of cassava may be achieved only in the upland areas of Akwa Ibom State due to continuous increase in rainfall as a result of climate change.

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Rainfall trend analysis using Mann-Kendall and Sen’s slope estimator test in West Kalimantan

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/893/1/012006 ◽

2021 ◽

Vol 893 (1) ◽

pp. 012006

Author(s):

F Aditya ◽

E Gusmayanti ◽

J Sudrajat

Keyword(s):

Climate Change ◽

Rainfall Variability ◽

Annual Rainfall ◽

Sen’S Slope Estimator ◽

West Kalimantan ◽

Rainfall Analysis ◽

Sen’S Slope ◽

Rainfall Trends ◽

Slope Estimator ◽

The Impact

Abstract Climate change has been a prominent issue in the last decade. Climate change on a global scale does not necessarily have the same effect in different regions. Rainfall is a crucial weather element related to climate change. Rainfall trends analysis is an appropriate step in assessing the impact of climate change on water availability and food security. This study examines rainfall variations and changes at West Kalimantan, focusing on Mempawah and Kubu Raya from 2000-2019. The Mann-Kendall (MK) and Sen's Slope estimator test, which can determine rainfall variability and long-term monotonic trends, were utilized to analyze 12 rainfall stations. The findings revealed that the annual rainfall pattern prevailed in all locations. Mempawah region tends to experience a downward trend, while Kubu Raya had an upward trend. However, a significant trend (at 95% confidence level) was identified in Sungai Kunyit with a slope value of -33.20 mm/year. This trend indicates that Sungai Kunyit will become drier in the future. The results of monthly rainfall analysis showed that significant upward and downward trends were detected in eight locations. Rainfall trends indicate that climate change has occurred in this region.

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Long term effect of climate change on rainfall in northwest Iraq

Open Engineering ◽

10.2478/s13531-013-0151-4 ◽

2014 ◽

Vol 4 (3) ◽

Cited By ~ 6

Author(s):

Nadhir Al-Ansari ◽

Mawada Abdellatif ◽

Salahalddin Ali ◽

Sven Knutsson

Keyword(s):

Climate Change ◽

Management Strategies ◽

Daily Rainfall ◽

Annual Rainfall ◽

Water Shortages ◽

Intergovernmental Panel ◽

Continuous Decrease ◽

Rainfall Trends ◽

Semi Arid Region

AbstractMiddle East, like North Africa, is considered as arid to semi-arid region. Water shortages in this region, represents an extremely important factor in stability of the region and an integral element in its economic development and prosperity. Iraq was an exception due to presence of Tigris and Euphrates Rivers. After the 1970s the situation began to deteriorate due to continuous decrease in discharges of these rivers, are expected to dry by 2040 with the current climate change. In the present paper, long rainfall trends up to the year 2099 were studied in Sinjar area, northwest of Iraq, to give an idea about its future prospects. Two emission scenarios, used by the Intergovernmental Panel on Climate Change (A2 and B2), were employed to study the long term rainfall trends in northwestern Iraq. All seasons consistently project a drop in daily rainfall for all future periods with the summer season is expected to have more reduction compared to other seasons. Generally the average rainfall trend shows a continuous decrease. The overall average annual rainfall is slightly above 210 mm. In view of these results, prudent water management strategies have to be adopted to overcome or mitigate consequences of future severe water crisis.

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Impacts of Climate Change on Rainfall Trends Under RCP Scenarios in Johor, Malaysia

10.21203/rs.3.rs-673266/v1 ◽

2021 ◽

Author(s):

Siti Nazahiyah Rahmat ◽

Aainaa Hatin Ahmad Tarmizi ◽

Nurul Nadrah Aqilah Tukimat

Keyword(s):

Climate Change ◽

General Circulation ◽

Historical Data ◽

Rainfall Variability ◽

Daily Rainfall ◽

Circulation Model ◽

Upward Trend ◽

Rcp Scenarios ◽

Rainfall Trends ◽

Impacts Of Climate Change

Abstract Changes in the spatial and temporal rainfall pattern affected by the climate change need to be investigated as its significant characteristics are often used for managing water resources. In this study, the impacts of climate change on rainfall variability in Johor was investigated by using General Circulation Model (GCM) on the availability of daily simulation for three representative concentration pathways (RCP) scenarios, RCP2.6, RCP4.5 and RCP8.5 for interval year of Δ2030, Δ2050 and Δ2080. In addition, the annual future rainfall trend for the first interval year of Δ2030 was also made. Daily rainfall series from eight (8) stations in Johor, Malaysia capturing 30 years period (1988-2017) with less than 10% missing data were chosen. The annual mean rainfall for RCP 2.6, 4.5 and 8.5 was predicted increase by 17.5%, 18.1% and 18.3%, respectively as compared to historical data. Moreover, the Mann-Kendall (MK) test was used to detect the trend and resulted in no trend for RCP2.6. Even so, RCP4.5 showed a significant upward trend in Muar and Kota Tinggi, and for RCP8.5, all regions were detected to have an upwards trend except for Pontian and Kluang. In general, the concentration of greenhouse gases from RCP8.5 gave the highest rainfall in future.

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Rainfall Variability and Trends over the African Continent Using TAMSAT Data (1983–2020): Towards Climate Change Resilience and Adaptation

Remote Sensing ◽

10.3390/rs14010096 ◽

2021 ◽

Vol 14 (1) ◽

pp. 96

Author(s):

Niranga Alahacoon ◽

Mahesh Edirisinghe ◽

Matamyo Simwanda ◽

ENC Perera ◽

Vincent R. Nyirenda ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Water Resource Management ◽

Rainfall Variability ◽

Decision Makers ◽

Annual Rainfall ◽

African Continent ◽

Climate Zones ◽

Mk Test ◽

Rainfall Trends

This study reveals rainfall variability and trends in the African continent using TAMSAT data from 1983 to 2020. In the study, a Mann–Kendall (MK) test and Sen’s slope estimator were used to analyze rainfall trends and their magnitude, respectively, under monthly, seasonal, and annual timeframes as an indication of climate change using different natural and geographical contexts (i.e., sub-regions, climate zones, major river basins, and countries). The study finds that the highest annual rainfall trends were recorded in Rwanda (11.97 mm/year), the Gulf of Guinea (river basin 8.71 mm/year), the tropical rainforest climate zone (8.21 mm/year), and the Central African region (6.84 mm/year), while Mozambique (−0.437 mm/year), the subtropical northern desert (0.80 mm/year), the west coast river basin of South Africa (−0.360 mm/year), and the Northern Africa region (1.07 mm/year) show the lowest annual rainfall trends. There is a statistically significant increase in the rainfall in the countries of Africa’s northern and central regions, while there is no statistically significant change in the countries of the southern and eastern regions. In terms of climate zones, in the tropical northern desert climates, tropical northern peninsulas, and tropical grasslands, there is a significant increase in rainfall over the entire timeframe of the month, season, and year. This implies that increased rainfall will have a positive effect on the food security of the countries in those climatic zones. Since a large percentage of Africa’s agriculture is based only on rainfall (i.e., rain-fed agriculture), increasing trends in rainfall can assist climate resilience and adaptation, while declining rainfall trends can badly affect it. This information can be crucial for decision-makers concerned with effective crop planning and water resource management. The rainfall variability and trend analysis of this study provide important information to decision-makers that need to effectively mitigate drought and flood risk.

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The Wet and Dry Spells across India during 1951–2007

Journal of Hydrometeorology ◽

10.1175/2009jhm1161.1 ◽

2010 ◽

Vol 11 (1) ◽

pp. 26-45 ◽

Cited By ~ 36

Author(s):

Nityanand Singh ◽

Ashwini Ranade

Keyword(s):

Climate Change ◽

Rainfall Intensity ◽

Total Duration ◽

Daily Rainfall ◽

Annual Rainfall ◽

Change Scenario ◽

Monsoon Period ◽

Northwestern India ◽

Area Of Interest ◽

Dry Spells

Abstract Characteristics of wet spells (WSs) and intervening dry spells (DSs) are extremely useful for water-related sectors. The information takes on greater significance in the wake of global climate change and climate-change scenario projections. The features of 40 parameters of the rainfall time distribution as well as their extremes have been studied for two wet and dry spells for 19 subregions across India using gridded daily rainfall available on 1° latitude × 1° longitude spatial resolution for the period 1951–2007. In a low-frequency-mode, intra-annual rainfall variation, WS (DS) is identified as a “continuous period with daily rainfall equal to or greater than (less than) daily mean rainfall (DMR) of climatological monsoon period over the area of interest.” The DMR shows significant spatial variation from 2.6 mm day−1 over the extreme southeast peninsula (ESEP) to 20.2 mm day−1 over the southern-central west coast (SCWC). Climatologically, the number of WSs (DSs) decreases from 11 (10) over the extreme south peninsula to 4 (3) over northwestern India as a result of a decrease in tropical and oceanic influences. The total duration of WSs (DSs) decreases from 101 (173) to 45 (29) days, and the duration of individual WS (DS) from 12 (18) to 7 (11) days following similar spatial patterns. Broadly, the total rainfall of wet and dry spells, and rainfall amount and rainfall intensity of actual and extreme wet and dry spells, are high over orographic regions and low over the peninsula, Indo-Gangetic plains, and northwest dry province. The rainfall due to WSs (DSs) contributes ∼68% (∼17%) to the respective annual total. The start of the first wet spell is earlier (19 March) over ESEP and later (22 June) over northwestern India, and the end of the last wet spell occurs in reverse, that is, earlier (12 September) from northwestern India and later (16 December) from ESEP. In recent years/decades, actual and extreme WSs are slightly shorter and their rainfall intensity higher over a majority of the subregions, whereas actual and extreme DSs are slightly (not significantly) longer and their rainfall intensity weaker. There is a tendency for the first WS to start approximately six days earlier across the country and the last WS to end approximately two days earlier, giving rise to longer duration of rainfall activities by approximately four days. However, a spatially coherent, robust, long-term trend (1951–2007) is not seen in any of the 40 WS/DS parameters examined in the present study.

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Farmers’ Perceptions on Climate Variability and Adaptation Strategies to Climate Change in Cinzana, Mali

Journal of Agricultural Studies ◽

10.5296/jas.v4i3.9331 ◽

2016 ◽

Vol 4 (3) ◽

pp. 13 ◽

Cited By ~ 1

Author(s):

Touré Halimatou ◽

Zampaligre Nouhoun ◽

Traoré Kalifa ◽

Kyei-Baffour Nicholas

Keyword(s):

Climate Change ◽

Climate Variability ◽

Meteorological Data ◽

Rainfall Variability ◽

Adaptation Strategies ◽

Sub Saharan Africa ◽

Farm Size ◽

Annual Rainfall ◽

Sub Saharan ◽

Future Economic Development

Several studies predict that climate change will highly affect the African continent. These changes in climate and climate variability may be challenging issues for future economic development of the continent in general, and particularly in the region of sub Saharan Africa. Offering a case study of Sahelian zone of Mali in the present study aimed to understand farmers’ perceptions of climate variability and change and to evaluate adaptation options used by farmers in the Cinzana commune of Mali. One hundred and nineteen farmers were interviewed using a questionnaire designed with six sections. The result showed that all farmers interviewed were aware of climate change and climate variability. The Farmers perceived a decrease in annual rainfall variability and an increase of temperature as main factors of climate change and climate variability. The observed meteorological data, showed a decrease of precipitation distribution during the last 14 years of which was observed by farmers. Several strategies such as selling animals, use of improved crop varieties, new activities (outside agriculture) and credit were the commonly preferred adaptation strategies to deal with climate change and variability. Factors surveyed, age, gender, education, household size, farm size were found to be significantly correlated to self-reported to adaptation.

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Likely Ranges of Climate Change in Bolivia

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-12-0224.1 ◽

2013 ◽

Vol 52 (6) ◽

pp. 1303-1317 ◽

Cited By ~ 25

Author(s):

Christian Seiler ◽

Ronald W. A. Hutjes ◽

Pavel Kabat

Keyword(s):

Climate Change ◽

Amazon Basin ◽

Rainfall Variability ◽

Annual Rainfall ◽

Amazon Forest ◽

Climate Change Scenarios ◽

Wet Season ◽

Global Circulation Models ◽

The Andes ◽

Interannual Rainfall Variability

AbstractBolivia is facing numerous climate-related threats, ranging from water scarcity due to rapidly retreating glaciers in the Andes to a partial loss of the Amazon forest in the lowlands. To assess what changes in climate may be expected in the future, 35 global circulation models (GCMs) from the third and fifth phases of the Coupled Model Intercomparison Project (CMIP3/5) were analyzed for the Bolivian case. GCMs were validated against observed surface air temperature, precipitation, and incoming shortwave (SW) radiation for the period 1961–90. Weighted ensembles were developed, and climate change projections for five emission scenarios were assessed for 2070–99. GCMs revealed an overall cold, wet, and positive-SW-radiation bias and showed no substantial improvement from the CMIP3 to the CMIP5 ensemble for the Bolivian case. Models projected an increase in temperature (2.5°–5.9°C) and SW radiation (1%–5%), with seasonal and regional differences. In the lowlands, changes in annual rainfall remained uncertain for CMIP3 whereas CMIP5 GCMs were more inclined to project decreases (−9%). This pattern also applied to most of the Amazon basin, suggesting a higher risk of partial biomass loss for the CMIP5 ensemble. Both ensembles agreed on less rainfall (−19%) during drier months (June–August and September–November), with significant changes in interannual rainfall variability, but disagreed on changes during wetter months (January–March). In the Andes, CMIP3 GCMs tended toward less rainfall (−9%) whereas CMIP5 tended toward more (+20%) rainfall during parts of the wet season. The findings presented here may provide inputs for studies of climate change impact that assess how resilient human and natural systems are under different climate change scenarios.

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Rainfall trends in hindsight and in foresight

10.5194/egusphere-egu2020-8753 ◽

2020 ◽

Author(s):

Theano Iliopoulou ◽

Demetris Koutsoyiannis

Keyword(s):

Daily Rainfall ◽

Predictive Performance ◽

Predictive Modelling ◽

Annual Rainfall ◽

Methodological Framework ◽

Rainfall Trends ◽

Out Of Sample ◽

Linear Trends

<p>Trends are customarily identified in rainfall data in the framework of explanatory modelling. Little insight however has been gained by this type of analysis with respect to their performance in foresight. In this work, we examine the out-of-sample predictive performance of linear trends through extensive investigation of 60 of the longest daily rainfall records available worldwide. We devise a systematic methodological framework in which linear trends are compared to simpler mean models, based on their performance in predicting climatic-scale (30-year) annual rainfall indices, i.e. maxima, totals, wet-day average and probability dry, from long-term daily records. Parallel experiments from synthetic timeseries are performed in order to provide theoretical insights to the results and the role of parsimony in predictive modelling is discussed. In line with the empirical findings, it is shown that, prediction-wise, simple is preferable to trendy.</p>

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Analysis of rainfall trends over Tripura

MAUSAM ◽

10.54302/mausam.v73i1.5078 ◽

2022 ◽

Vol 73 (1) ◽

pp. 27-36

Author(s):

RANJAN PHUKAN ◽

D. SAHA

Keyword(s):

Heavy Rainfall ◽

Monsoon Season ◽

Rainfall Variability ◽

Kendall Test ◽

Annual Rainfall ◽

The North ◽

Rainfall Trends ◽

Annual Scale ◽

Increasing Trends ◽

Rainy Days

Rainfall in India has very high temporal and spatial variability. The rainfall variability affects the livelihood and food habits of people from different regions. In this study, the rainfall trends in two stations in the north-eastern state of Tripura, namely Agartala and Kailashahar have been studied for the period 1955-2017. The state experiences an annual mean of more than 2000 mm of rainfall, out of which, about 60% occurs during the monsoon season and about 30% in pre-monsoon. An attempt has been made to analyze the trends in seasonal and annual rainfall, rainy days and heavy rainfall in the two stations, during the same period.Non-parametric Mann-Kendall test has been used to find out the significance of these trends. Both increasing and decreasing trends are observed over the two stations. Increasing trends in rainfall, rainy days and heavy rainfall are found at Agartala during pre-monsoon season and decreasing trends in all other seasons and at annual scale. At Kailashahar, rainfall amount (rainy days & heavy rainfall) is found to be increasing during pre-monsoon and monsoon seasons (pre-monsoon season). At annual scale also, rainfall and rainy days show increasing trends at Kailashahar. The parameters are showing decreasing trends during all other seasons at the station. Rainy days over Agartala show a significantly decreasing trend in monsoon, whereas no other trend is found to be significant over both the stations.

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