Spatial-temporal trends analysis of flood events in the Republic of Armenia in the context of climate change

Abstract The primary goal of the study is to analyze the spatial-temporal trends and distribution of flood events in the context of climate change in Armenia. For that purpose, some meteorological parameters, physical-geographical factors and the flood events data were studied for the 1994–2019 period. The linear trends demonstrate an increasing tendency of air temperature and precipitation. Those trends expressed increased flood occurrences, especially for the 2000s, whereas the Mann–Kendall (MK) trend test reveals no significant change. The number of flood events reaches its maximum in 2011 with its peak in May. Out of 191 flood events, half of the occurrences are recorded in the flat areas and southern aspects of the mountains (22% of the country's territory). There is a certain clustering of flood events in the areas with up to 5° slopes (66% of flood events). The most flood vulnerable areas were analyzed and mapped via Geographical Information System (GIS). The GIS-based mapping shows the location of flood vulnerable areas in the central, northern parts of the country, and the coastal areas of Lake Sevan. Our methodological approach elaborates the localization of flood-prone sites. It can be used for the flood hazard assessment mapping and risk management.

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Assessment of the impact of climate change on the freshwater availability of Kaduna River basin, Nigeria

Journal of Water and Land Development ◽

10.2478/jwld-2018-0047 ◽

2018 ◽

Vol 38 (1) ◽

pp. 105-114 ◽

Cited By ~ 2

Author(s):

Gloria C. Okafor ◽

Kingsley N. Ogbu

Keyword(s):

Climate Change ◽

River Basin ◽

Water Availability ◽

Hydrological Cycle ◽

Temporal Trends ◽

Kendall Test ◽

Well Being ◽

Trend Test ◽

Climate Indices ◽

The Impact

AbstractChanges in runoff trends have caused severe water shortages and ecological problems in agriculture and human well-being in Nigeria. Understanding the long-term (inter-annual to decadal) variations of water availability in river basins is paramount for water resources management and climate change adaptation. Climate change in Northern Nigeria could lead to change of the hydrological cycle and water availability. Moreover, the linkage between climatic changes and streamflow fluctuations is poorly documented in this area. Therefore, this study examined temporal trends in rainfall, temperature and runoff records of Kaduna River basin. Using appropriate statistical tools and participatory survey, trends in streamflow and their linkages with the climate indices were explored to determine their amplifying impacts on water availability and impacts on livelihoods downstream the basin. Analysis indicate variable rainfall trend with significant wet and dry periods. Unlike rainfall, temperature showed annual and seasonal scale statistically increasing trend. Runoff exhibit increasing tendency but only statistically significant on annual scale as investigated with Mann–Kendall trend test. Sen’s estimator values stood in agreement with Mann–Kendall test for all variables. Kendall tau and partial correlation results revealed the influence of climatic variables on runoff. Based on the survey, some of the hydrological implications and current water stress conditions of these fluctuations for the downstream inhabitants were itemized. With increasing risk of climate change and demand for water, we therefore recommend developing adaptive measures in seasonal regime of water availability and future work on modelling of the diverse hydrological characteristics of the entire basin.

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Climate Change, Flood Risk Prediction and Acute Gastrointestinal Infection in the Republic of Ireland, 2008-2017

10.5194/egusphere-egu2020-10162 ◽

2020 ◽

Author(s):

Martin Boudou ◽

Eimear Cleary ◽

Paul Hynds ◽

Jean O'Dwyer ◽

Patricia Garvey ◽

...

Keyword(s):

Climate Change ◽

Risk Assessment ◽

Return Period ◽

Flood Risk ◽

Geographical Information ◽

Risk Exposure ◽

Flood Risk Assessment ◽

Republic Of Ireland ◽

Risk Probability ◽

The Republic

Environmentally associated infectious diseases, including those driven by extreme weather events, represent a critical challenge for public health as their source and transmission are frequently sporadic and associated mechanisms often not well understood. Over the past decade, the Republic of Ireland (ROI) has persistently reported the highest incidence of confirmed verotoxigenic E. coli (VTEC) and cryptosporidiosis infection in the European Union. Moreover, recent climate projections indicate that the incidence, severity and timing of extreme rainfall events and flooding will increase dramatically over the next century, with Ireland forecast to be the second most affected European country with respect to the mean proportion of the population residing in flood-prone areas by 2100. This study aimed to assess the association(s) between potential flood risk exposure and the spatial occurrence of confirmed VTEC and cryptosporidiosis infection in Ireland over a 10-year period (2008-2017).In 2012, the Irish Office of Public Works (OPW) initiated the National Catchment Flood Risk Assessment and Management (CFRAM) Programme within the framework of the Flood Directive (2007/60/CE), with high-resolution flood maps produced for coastal and fluvial risks and three risk scenarios based on calculated return periods (low, medium and high probability). Small area identifiers (national census area centroids) were used to attach anonymised spatially referenced case data to CFRAM polygons using Geographical Information Systems (GIS) to produce an anonymised dataframe of confirmed infection events linked to geographically explicit flood risk attributes. Generalised linear modelling with binary link functions (infection presence/absence) were used to calculate probabilistic odds ratios (OR) between flood risk (presence/absence and scenarios) and confirmed human infection.Preliminary results indicate a clear relationship between both infections and hydrological risk. Over one third of all infection cases were reported within areas exposed to flood risk (VTEC 948/2755 cases; cryptosporidiosis 1548/4509 cases). Census areas categorised by a high (10-year Return Period) fluvial flood risk probability exhibited significantly higher incidence rates for both VTEC (OR: 1.83, P = 0.0003) and cryptosporidiosis (OR: 1.80, P = 0.0015). Similarly, areas characterised by low (1000-year Return Period) coastal flood risk probability were over twice as likely to report &#8805;1 confirmed case of cryptosporidiosis during the study period (OR: 2.2, P= 0.003). Space-time scan statistics (temporally-specific spatial autocorrelation) indicate an unseasonal peak of cryptosporidiosis cases occurring during April 2016, a majority of which took place within or adjacent to high flood risk areas (56% of total cases), revealing a potential relationship with the exceptional flooding events experienced during winter 2015-2016 (November-January). Further work will seek to identify the individual/combined flood risk (CFRAM) elements most significantly associated with the incidence of infections.Flood risk assessment mapping may represent an innovative approach to assessing the human health impacts of flood risk exposure and climate change. The outcomes of this study will contribute to predictive modelling of VTEC and cryptosporidiosis in Ireland, thus aiding surveillance and control of these diseases in the future, and the causative nature of regional hydrology and climate. &#160;&#160;

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Flood risk management under climate change: a hydro-economic perspective

Water Science & Technology Water Supply ◽

10.2166/ws.2018.003 ◽

2018 ◽

Vol 18 (5) ◽

pp. 1832-1840 ◽

Cited By ~ 1

Author(s):

Rohini P. Devkota ◽

Tek Maraseni

Keyword(s):

Climate Change ◽

River Basin ◽

Flood Hazard ◽

Methodological Approach ◽

Extreme Rainfall ◽

Developed Countries ◽

Flood Management ◽

Policy Implications ◽

Extreme Rainfall Events ◽

Management Plans

Abstract Most developing countries, like Nepal, are expected to experience the greatest impact of climate change (CC) sooner and on a greater magnitude than other developed countries. Increase in the magnitude and frequency of extreme rainfall events is likely to increase the risk of flooding in rivers. The West Rapti River basin is one of the most flood prone and also one of the most dynamic and economically important basins of Nepal. This study elicits the willingness to pay (WTP) from the local people in the basin to reduce risks from possible floods due to CC. The WTP for flood mitigation in different flood hazard zones and flood scenarios were determined using referendum method and a face to face questionnaire survey. From a total of 720 households across all flood zones, a stratified randomly selected sample of 210 households was surveyed. The sample included households from a range of socio-economic backgrounds. The average WTP varied by flood hazard zone and within each zone, by CC-induced flood scenarios. The average WTP of respondents was highest for the critical flood prone zone, followed by moderate and low flood prone zones. Similarly, within each zone, the average WTP increased with increasing flood magnitudes due to CC. The variation of average WTP of respondents in different flood prone zones and scenarios indicate different levels of perceived severity. Moreover, the introduction of the concept of ‘man-day’ or ‘labour-day’ in WTP research is a novel and applicable methodological approach, particularly in the South Asian region. The findings of this study are useful for policy implications for the design of participatory flood management plans in the river basin.

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Climatic Anomalies and Glacial Dynamics in the Himalayan Region Northern Pakistan: A Spatio-Statistical Approach

Indonesian Journal of Geography ◽

10.22146/ijg.59575 ◽

2021 ◽

Vol 53 (2) ◽

Author(s):

Zarka Mukhtar ◽

Fazlul Haq ◽

Syed Ali Asad Naqvi ◽

Munazza Afreen

Keyword(s):

Temporal Trend ◽

Meteorological Data ◽

Ice Cover ◽

Himalayan Region ◽

Geographical Information ◽

Trend Test ◽

Temperature And Precipitation ◽

Glacial Dynamics ◽

Slope Estimator ◽

Climatic Elements

Glaciers are always climate-sensitive and affected by minor changes in temperature and other climatic elements. Past studies on the northern mountain ranges of Pakistan reveal changes in climatic patterns in and around these ranges. In this study, an attempt is made to explore and assess the temporal and spatial fluctuations occurring in the ice cover of the Himalayan Region of Pakistan as a result of changes in climatic pattern. Satellite imageries and meteorological data were used to explore the dynamics of both the ice cover and climatic elements. Remote Sensing and Geographical Information System were used to detect changes in snow cover both spatially and temporally. Various statistical techniques, mainly Mann Kendall Trend Test and Sen’s Slope Estimator, were used to analyze the temporal trend of climatic elements. Moreover, correlation and regression analysis were applied to establish the relationship between climate and ice cover. Analysis of the data reveals that the temporal trend in ice cover is not monotonic as there is glacial advancement in certain years while retreating in others. Moreover, it was found out that climatic elements such as temperature and precipitation have recorded changes during the past few decades.

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Representation of certain indicators o climate change in the area of eastern Serbia in the period 1991-2012 compared to the reference period 1961-1990

Glasnik srpskog geografskog drustva ◽

10.2298/gsgd140710005n ◽

2014 ◽

Vol 94 (4) ◽

pp. 121-145

Author(s):

Zoran Nikic ◽

Мilenа Аndjelic ◽

Ljubomir Letic ◽

Vaso Мrvaljevic ◽

Vesna Nikolic

Keyword(s):

Climate Change ◽

Comparative Analysis ◽

Relative Humidity ◽

Air Temperature ◽

Reference Period ◽

Temperature And Precipitation ◽

Four Seasons ◽

The Republic ◽

Climatic Elements

Climate change that has occurred at the end of the last and at the beginning of this century, among other things, has a certain impact on forests as well. For the territory of Eastern Serbia, for two periods of climate observations, the reference period 1961-1990 and the period 1991-2012, a comparative analysis of the following climatic elements was done: air temperature, amount of precipitation and relative humidity of air. Calculations were performed on the basis of collected and systematized data from 11 meteorological stations (6 synoptic/main climatological and 5 regular climatological) that were part of the Republic Hydrometeorological Service, situated in the area of Eastern Serbia. Analysis of the anomalies of air temperature and precipitation as indicators of climate change for the period 1991-2012 compared to the reference period 1961-1990 was done separately for each of the four seasons (winter, spring, summer, autumn) and summarized for each period. The results of the comparative analysis show that in the period 1991-2012 compared to the reference period 1961-1990, there was an increase in the average annual air temperature, as well as the increase in the average air temperature for all four seasons, and a decrease in the average annual amounts of precipitation and the decrease in the relative humidity of air.

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Using Integrated Hydrological Models to Assess the Impacts of Climate Change on Discharges and Extreme Flood Events in the Upper Yangtze River Basin

Water ◽

10.3390/w13030299 ◽

2021 ◽

Vol 13 (3) ◽

pp. 299

Author(s):

Yanjuan Wu ◽

Gang Luo ◽

Cai Chen ◽

Zheng Duan ◽

Chao Gao

Keyword(s):

Climate Change ◽

Climate Models ◽

Global Climate ◽

Yangtze River Basin ◽

Global Climate Models ◽

Hydrological Models ◽

Flood Events ◽

Temperature And Precipitation ◽

Extreme Flood ◽

Impacts Of Climate Change

Amongst the impacts of climate change, those arising from extreme hydrological events are expected to cause the greatest impacts. To assess the changes in temperature and precipitation and their impacts on the discharge in the upper Yangtze Basin from pre-industrial to the end of 21st century, four hydrological models were integrated with four global climate models. Results indicated that mean discharge was simulated to increase slightly for all hydrological models forced by all global climate models during 1771–1800 and 1871–1900 relative to the 1971–2000 reference period, whereas the change directions in mean discharge were not consistent among the four global climate models during 2070–2099, with increases from HadGEM2-ES and MIROC5, and decreases from GFDL-ESM2M and IPSL-CM5A-LR. Additionally, our results indicated that decreases in precipitation may always result in the decrease in mean discharge, but increases in precipitation did not always lead to increases in discharge due to high temperature rise. The changes in extreme flood events with different return intervals were also explored. These extreme events were projected to become more intense and frequent in the future, which could have potential devastating impacts on the society and ecosystem in this region.

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Analysis of Climate Change’s Effect on Flood Risk. Case Study of Reinosa in the Ebro River Basin

Water ◽

10.3390/w12041114 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1114

Author(s):

Eduardo Lastrada ◽

Guillermo Cobos ◽

Francisco Javier Torrijo

Keyword(s):

Climate Change ◽

River Basin ◽

Flood Risk ◽

Climate Models ◽

Cost Benefit Analysis ◽

Flood Hazard ◽

Cost Benefit ◽

Economic Damage ◽

Temperature And Precipitation

Floods are one of the natural hazards that could be most affected by climate change, causing great economic damage and casualties in the world. On December 2019 in Reinosa (Cantabria, Spain), took place one of the worst floods in memory. Implementation of DIRECTIVE 2007/60/EC for the assessment and management of flood risks in Spain enabled the detection of this river basin with a potential significant flood risk via a preliminary flood risk assessment, and flood hazard and flood risk maps were developed. The main objective of this paper is to present a methodology to estimate climate change’s effects on flood hazard and flood risk, with Reinosa as the case study. This river basin is affected by the snow phenomenon, even more sensitive to climate change. Using different climate models, regarding a scenario of comparatively high greenhouse gas emissions (RCP8.5), with daily temperature and precipitation data from years 2007–2070, and comparing results in relative terms, flow rate and flood risk variation due to climate change are estimated. In the specific case of Reinosa, the MRI-CGCM3 model shows that climate change will cause a significant increase of potential affected inhabitants and economic damage due to flood risk. This evaluation enables us to define mitigation actions in terms of cost–benefit analysis and prioritize the ones that should be included in flood risk management plans.

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Spring Snowmelt Flood Estimate in the Upper Heihe River under Climate Change Scenarios

10.5194/egusphere-egu2020-4604 ◽

2020 ◽

Author(s):

Guangxi Zhu

Keyword(s):

Climate Change ◽

Flood Hazard ◽

Precipitation Forecast ◽

Future Climate Change ◽

Heihe River ◽

Climate Change Scenarios ◽

Return Periods ◽

Temperature And Precipitation ◽

Spring Runoff ◽

Flood Intensity

With the climate warming, high mountainous areas, including cryosphere, show more frequent and early outbreaks trend in flood hazard, cursing more losses to downstream areas. Based on meteorological, hydrological and MODIS snow cover data, using the snowmelt runoff model (SRM) to simulate and verify the spring runoff result during the snowmelt period from 1990 to 2012 in the upper Heihe River. SRM model simulates results shows it has a high accuracy (NSE = 0.7229), which can be used to predict the future flood intensity changes in studying area. In order to predict the trends of Heihe River Basin in flood return periods under the different future climate change scenarios, analyze used the temperature and precipitation forecast data. By the end of this century, the result of flood runoff shows differently according to climate change scenarios compared with the basic period. In RCP 2.6, due to the small changes of the temperature and precipitation, flood intensity will change slightly around 10% in all return periods; in RCP 4.5, it will increase about 20%; in RCP 8.5, return periods may be rise over 30%.

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Spatio-Temporal Variability of Drought in Pakistan Using Standardized Precipitation Evapotranspiration Index

Applied Sciences ◽

10.3390/app9214588 ◽

2019 ◽

Vol 9 (21) ◽

pp. 4588 ◽

Cited By ~ 8

Author(s):

Shoaib Jamro ◽

Ghulam Hussain Dars ◽

Kamran Ansari ◽

Nir Y. Krakauer

Keyword(s):

Climate Change ◽

Temporal Trends ◽

Trend Test ◽

Standardized Precipitation Evapotranspiration Index ◽

Northern Areas ◽

Tree Edge ◽

Edge Removal ◽

History Of ◽

Drying Trend ◽

Spatio Temporal

Pakistan is among the top ten countries adversely affected by climate change. More specifically, there is concern that climate change may cause longer and severer spells of droughts. To quantify the change in the characteristics of droughts in Pakistan over the years, we have evaluated spatio-temporal trends of droughts in Pakistan over the period 1902–2015 using Standardized Precipitation Evapotranspiration Index (SPEI). Additionally, the Spatial “K” luster Analysis using Tree Edge Removal (SKATER) method was employed to regionalize droughts into five contiguous zones. The run theory was then applied to each zone to identify drought events and characterize them in terms of duration, severity, intensity, and peak. Moreover, the Modified Mann–Kendall trend test was applied to identify statistically significant trends in SPEI and drought characteristics in each zone. It was found that the southern areas of Pakistan, encompassing Sindh and most of Baluchistan, have experienced a decrease in SPEI, indicating a drying trend. Central Pakistan has witnessed a wetting trend as demonstrated by an increase in SPEI over time, whereas no statistically significant trend was observed for the northern areas of Pakistan. On a zonal basis, the longest duration drought to occur in Pakistan lasted 22 months in zone 5 (Sindh) from 1968 to 1970. In addition, the drought of 1920 and 2000 can be said to be the worst drought in the history of the region as it affected all the zones and lasted for more than 10-months in three zones.

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Climate Change-Induced Agricultural Drought over Moist-Cool and Moist-Warm Climatic Zones: A Case Study in Ale and Adami-Tulu Woredas, in Oromia National Regional State, Ethiopia

Caraka Tani Journal of Sustainable Agriculture ◽

10.20961/carakatani.v34i2.29344 ◽

2019 ◽

Vol 34 (2) ◽

pp. 188

Author(s):

Fedhasa Benti ◽

Achalu Chimdi

Keyword(s):

Climate Change ◽

Potential Evapotranspiration ◽

Temperature Data ◽

Agricultural Drought ◽

Drought Indices ◽

Trend Test ◽

Climatic Zones ◽

Temperature And Precipitation ◽

Precipitation And Temperature

Frequency and intensity of drought have troubled sustainable agriculture and worsened food insecurity of Ethiopians. This study aimed to investigate climate change-induced agricultural drought over the moist-cool and moist-warm climatic zones, using historical precipitation and temperature data recorded in the crop growing months for 35 years. The changes of temperatures and precipitation were analyzed using Mann Kendall trend test. Agricultural drought indices were analyzed using R-model by withdrawing potential evapotranspiration from precipitation to determine the existing water balance. The values of drought indices were used to characterize the duration, severity, intensity and trends of agricultural drought. Results showed that the changes in maximum and minimum temperatures and precipitation were significantly stronger in the Ale Woreda (P<0.05). However, minimum temperature and precipitation in Adami-Tulu did not noticeably change. The spatial drought events occurred more widely in Ale than in Adami Tulu. The events occurred 12 and 17 times with cumulative severity indices of 41.95 and 48.22 in Ale and Adami-Tulu, respectively. Agricultural drought intensities of the two districts were labeled as “severe” and “moderate dry”, for Ale and Adami-Tulu, respectively. The intensity of drought in Ale district significantly increased (P<0.05) and that in Adami-Tulu negligibly changed. Therefore, the study explicitly showed that more changes in temperature and precipitation aggravated agricultural drought in Ale than in Adami-Tulu more intensely and it is suggested that more attention shall be paid to Ale Woreda.

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