Flood Risk Characterization of Highly Flood-prone Data Scarce Region under Changing Climate

It is evident that changes in climate alter the incidence of hydro-climatic extreme events, specifically floods, which are likely to cause irreparable socio-economic and ecological damages. With a 7,516 km coastline that is prone to climate-mediated disturbances and cyclones, the eastern coast of the Indian subcontinent is comparatively more vulnerable to the changing climate and land use with higher incidences of extensive flooding. Therefore, the policy-makers and decision-making authorities are dependent on the scientific community to provide reliable estimates of hydro-meteorological variables for simulating extreme events under the impact of climate change. However, a comprehensive flood risk framework at a finer administrative level is not yet available under the Indian scenario that assesses the changing dynamics and complexities of different components of climatic risk (hazard, vulnerability, and exposure). The present study attempts to demonstrate a proposed framework of flood risk assessment for a highly flood-prone deltaic region of Mahanadi River Basin, India, under climate change scenarios for near-future (the 2040s) at present-day vulnerability and exposure status. It was noted that changes in future flood risk are highly influenced by the vulnerability and exposure status of the region. Lower vulnerability and exposure in coastal sub-districts reduces the overall risk even if a higher flood hazard is observed. Under both future scenarios, RCP 4.5 and 8.5, the number of villages under high hazard zones with greater flood magnitude has increased. Therefore, it thrusts upon the need to adopt stringent actions for devising better adaptation strategies and sustainable planning which can aid in lowering the vulnerability of the region to future floods.

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Assessing the global risk of climate change to re/insurers using catastrophe models and hazard maps

10.5194/egusphere-egu2020-5323 ◽

2020 ◽

Author(s):

Sarah Jones ◽

Emma Raven ◽

Jane Toothill

Keyword(s):

Climate Change ◽

Sea Level ◽

Flood Risk ◽

River Flow ◽

Climate Model ◽

Flood Hazard ◽

Insurance Industry ◽

Global Climate Model ◽

Hazard Maps ◽

The Impact

In 2018 worldwide natural catastrophe losses were estimated at around USD $155 billion, resulting in the fourth-highest insurance payout on sigma records, and in 2020 JBA Risk Management (JBA) estimate 2 billion people will be at risk to inland flooding. By 2100, under a 1.5&#176;C warming scenario, the cost of coastal flooding alone as a result of sea level rise could reach USD $10.2 trillion per year, assuming no further adaptation. It is therefore imperative to understand the impact climate change may have on global flood risk and insured losses in the future.The re/insurance industry has an important role to play in providing financial resilience in a changing climate. Although integrating climate science into financial business remains in its infancy, modelling companies like JBA are increasingly developing new data and services to help assess the potential impact of climate change on insurance exposure.We will discuss several approaches to incorporating climate change projections with flood risk data using examples from research collaborations and commercial projects. Our case studies will include: (1) building a national-scale climate change flood model through the application of projected changes in river flow, rainfall and sea level to the stochastic event set in the model, and (2) using Global Climate Model data to adjust hydrological inputs driving 2D hydraulic models to develop climate change flood hazard maps.These tools provide outputs to meet different needs, and results may sometimes invoke further questions. For example: how can an extreme climate scenario produce lower flood risk than a conservative one? Why may adjacent postcodes' flood risk differ? We will explore the challenges associated with interpreting these results and the potential implications for the re/insurance industry.

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Using the UKCP09 probabilistic scenarios to model the amplified impact of climate change on drainage basin sediment yield

Hydrology and Earth System Sciences ◽

10.5194/hess-16-4401-2012 ◽

2012 ◽

Vol 16 (11) ◽

pp. 4401-4416 ◽

Cited By ~ 42

Author(s):

T. J. Coulthard ◽

J. Ramirez ◽

H. J. Fowler ◽

V. Glenis

Keyword(s):

Climate Change ◽

Return Period ◽

Extreme Events ◽

Sediment Yield ◽

Drainage Basin ◽

Climate Change Scenarios ◽

Hourly Rainfall ◽

Baseline Values ◽

The Impact ◽

Emissions Scenario

Abstract. Precipitation intensities and the frequency of extreme events are projected to increase under climate change. These rainfall changes will lead to increases in the magnitude and frequency of flood events that will, in turn, affect patterns of erosion and deposition within river basins. These geomorphic changes to river systems may affect flood conveyance, infrastructure resilience, channel pattern, and habitat status as well as sediment, nutrient and carbon fluxes. Previous research modelling climatic influences on geomorphic changes has been limited by how climate variability and change are represented by downscaling from global or regional climate models. Furthermore, the non-linearity of the climatic, hydrological and geomorphic systems involved generate large uncertainties at each stage of the modelling process creating an uncertainty "cascade". This study integrates state-of-the-art approaches from the climate change and geomorphic communities to address these issues in a probabilistic modelling study of the Swale catchment, UK. The UKCP09 weather generator is used to simulate hourly rainfall for the baseline and climate change scenarios up to 2099, and used to drive the CAESAR landscape evolution model to simulate geomorphic change. Results show that winter rainfall is projected to increase, with larger increases at the extremes. The impact of the increasing rainfall is amplified through the translation into catchment runoff and in turn sediment yield with a 100% increase in catchment mean sediment yield predicted between the baseline and the 2070–2099 High emissions scenario. Significant increases are shown between all climate change scenarios and baseline values. Analysis of extreme events also shows the amplification effect from rainfall to sediment delivery with even greater amplification associated with higher return period events. Furthermore, for the 2070–2099 High emissions scenario, sediment discharges from 50-yr return period events are predicted to be 5 times larger than baseline values.

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Modelling the impact of climate change on rice production in India

MAUSAM ◽

10.54302/mausam.v52i1.1693 ◽

2021 ◽

Vol 52 (1) ◽

pp. 263-274

Author(s):

L. S. RATHORE ◽

K. K. SINGH ◽

S. A. SASEENDRAN ◽

A. K. BAXLA

Keyword(s):

Climate Change ◽

South India ◽

Model Simulation ◽

Indian Subcontinent ◽

Central India ◽

Ocean Model ◽

Change Scenario ◽

Climate Change Scenarios ◽

Business As Usual ◽

The Impact

The CERES-Rice crop simulation model, calibrated and validated for the varieties PR106 in NW India. IR36 in central India and Jaya in south India, is used for nalysing the effect of climate change on rice productivity in the country. Plausible climate change scenario for the Indian subcontinent as expected by the middle of the next century taking into account the projected emissions of greenhouse gases and sulphate aerosols, in a coupled atmosphere-ocean model experiment performed at Deutsches Klimarechenzentrum, Germany, is adopted for the study. The adopted scenario represented an increase in monsoon seasonal mean surface temperature of the order of about 1.5° C over the south India and 1°C over northwest and central India in the decade 2040-49 with respect to the 1980s and an increase in rainfall of the order of 2 mm per day over south India while the simulated decrease of the order about -1 mm and -1.5 mm over northwest and central India respectively. The IPCC Business-as-usual scenario projection of plant usable concentration of CO2 about 460 PPM by the middle fo the next century are also used in the crop model simulation (CERES - Rice V3 Model). Simulation studies carried out with the climate change scenarios over different parts of the country are analysed and interpreted.

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The Impact of Climate Change on Reservoir Inflows Using Multi Climate-Model under RCPs’ Including Extreme Events—A Case of Mangla Dam, Pakistan

10.20944/preprints201608.0200.v1 ◽

2016 ◽

Author(s):

Muhammad Babur ◽

Mukand Singh Babel ◽

Sangam Shrestha ◽

Akiyuki Kawasaki ◽

Nitin Kumar Tripathi

Keyword(s):

Climate Change ◽

Extreme Events ◽

Swat Model ◽

Spring Discharge ◽

Climatic Data ◽

Climate Change Scenarios ◽

Global Circulation Models ◽

Wide Range ◽

Rcp 8.5 ◽

The Impact

Assessment of extreme events and climate change on reservoir inflow is important for water and power stressed countries. Projected climate is subject to uncertainties related to climate change scenarios and Global Circulation Models (GCMs’). Extreme climatic events will increase with the rise in temperature as mentioned in the AR5 of the IPCC. This paper discusses the consequences of climate change that include extreme events on discharge. Historical climatic and gauging data were collected from different stations within a watershed. The observed flow data was used for calibration and validation of SWAT model. Downscaling was performed on future GCMs’ temperature and precipitation data, and plausible extreme events were generated. Corrected climatic data was applied to project the influence of climate change. Results showed a large uncertainty in discharge using different GCMs’ and different emissions scenarios. The annual tendency of the GCMs’ is bi-vocal: six GCMs’ projected a rise in annual flow, while one GCM projected a decrease in flow. The change in average seasonal flow is more as compared to annual variations. Changes in winter and spring discharge are mostly positive, even with the decrease in precipitation. The changes in flows are generally negative for summer and autumn due to early snowmelt from an increase in temperature. The change in average seasonal flows under RCPs’ 4.5 and 8.5 are projected to vary from -29.1 to 130.7% and -49.4 to 171%, respectively. In the medium range (RCP 4.5) impact scenario, the uncertainty range of average runoff is relatively low. While in the high range (RCP 8.5) impact scenario, this range is significantly larger. RCP 8.5 covered a wide range of uncertainties, while RCP 4.5 covered a short range of possibilities. These outcomes suggest that it is important to consider the influence of climate change on water resources to frame appropriate guidelines for planning and management.

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Using the UKCP09 probabilistic scenarios to model the amplified impact of climate change on river basin sediment yield

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-9-8799-2012 ◽

2012 ◽

Vol 9 (7) ◽

pp. 8799-8840 ◽

Cited By ~ 2

Author(s):

T. J. Coulthard ◽

J. Ramirez ◽

H. J. Fowler ◽

V. Glenis

Keyword(s):

Climate Change ◽

Return Period ◽

Extreme Events ◽

Sediment Yield ◽

Climate Models ◽

Climate Change Scenarios ◽

Hourly Rainfall ◽

Baseline Values ◽

The Impact ◽

Emissions Scenario

Abstract. Precipitation intensities and the frequency of extreme events are projected to increase under climate change. These rainfall changes will lead to increases in the magnitude and frequency of flood events that will, in turn, affect patterns of erosion and deposition within river basins. These geomorphic changes to river systems may affect flood conveyance, infrastructure resilience, channel pattern, and habitat status, as well as sediment, nutrient and carbon fluxes. Previous research modelling climatic influences on geomorphic changes has been limited by how climate variability and change are represented by downscaling from Global or Regional Climate Models. Furthermore, the non-linearity of the climatic, hydrological and geomorphic systems involved generate large uncertainties at each stage of the modelling process creating an uncertainty "cascade". This study integrates state-of-the-art approaches from the climate change and geomorphic communities to address these issues in a probabilistic modelling study of the Swale catchment, UK. The UKCP09 weather generator is used to simulate hourly rainfall for the baseline and climate change scenarios up to 2099, and used to drive the CAESAR landscape evolution model to simulate geomorphic change. Results show that winter rainfall is projected to increase, with larger increases at the extremes. The impact of the increasing rainfall is amplified through the translation into catchment runoff and in turn sediment yield with a 100% increase in catchment mean sediment yield predicted between the baseline and the 2070–2099 High emissions scenario. Significant increases are shown between all climate change scenarios and baseline values. Analysis of extreme events also shows the amplification effect from rainfall to sediment delivery with even greater amplification associated with higher return period events. Furthermore, for the 2070–2099 High emissions scenario, sediment discharges from 50 yr return period events are predicted to be 5 times larger than baseline values.

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Flood Hazard Assessment Under Climate Change Scenarios in Kelantan River Basin, Malaysia

10.21203/rs.3.rs-858810/v1 ◽

2021 ◽

Author(s):

Tze Huey Tam ◽

Muhammad Zulkarnain Abdul Rahman ◽

Sobri Harun ◽

Sophal Try ◽

Shamsuddin Shahid ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Hydrological Cycle ◽

Flood Hazard ◽

Climate Change Scenarios ◽

Flood Hazards ◽

Distributed Hydrological Model ◽

Design Rainfall ◽

Kelantan River Basin ◽

The Impact

Abstract Climate change can significantly alter the hydrological cycle and lead to severe hydrological disasters. This study aims to determine the impact of climate change on flood hazards in the Kelantan River Basin of Malaysia. The Climate Change Factor (CCF) is used to calculate 24-hour design rainfall with 50, 100 and 200-year return periods. A distributed hydrological model, Rainfall-Runoff-Inundation (RRI), is used to simulate flood inundation under current and future climate scenarios. The results indicate an increase in 50, 100, and 200 years, design rainfall, streamflow and flood hazard. The expected design rainfall and streamflow for 50, 100, and 200 years would increase by 36.6%, 37.9%, 42.7%, and 43.2%, 32.7%, 36.5%, respectively. Flood hazard is spatially variable in the Kelantan River Basin. Tanah Merah is the town that would face a significant increase in future flooding. The findings of this study can aid relevant agencies and government departments to comprehend the current and future flood hazard situation in the Kelantan River Basin. It would also assist them in formulating appropriate flood management strategies to mitigate future severe flood hazards.

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Quantification of increased flood risk due to global climate change for urban river management planning

Water Science & Technology ◽

10.2166/wst.2011.172 ◽

2011 ◽

Vol 63 (12) ◽

pp. 2967-2974 ◽

Cited By ~ 17

Author(s):

M. Morita

Keyword(s):

Climate Change ◽

Global Climate Change ◽

Flood Risk ◽

Flood Control ◽

Global Climate ◽

Flood Damage ◽

Climate Change Scenarios ◽

Return Periods ◽

Damage Potential ◽

The Impact

Global climate change is expected to affect future rainfall patterns. These changes should be taken into account when assessing future flooding risks. This study presents a method for quantifying the increase in flood risk caused by global climate change for use in urban flood risk management. Flood risk in this context is defined as the product of flood damage potential and the probability of its occurrence. The study uses a geographic information system-based flood damage prediction model to calculate the flood damage caused by design storms with different return periods. Estimation of the monetary damages these storms produce and their return periods are precursors to flood risk calculations. The design storms are developed from modified intensity–duration–frequency relationships generated by simulations of global climate change scenarios (e.g. CGCM2A2). The risk assessment method is applied to the Kanda River basin in Tokyo, Japan. The assessment provides insights not only into the flood risk cost increase due to global warming, and the impact that increase may have on flood control infrastructure planning.

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Urban Geometry Optimization to Mitigate Climate Change: Towards Energy-Efficient Buildings

Sustainability ◽

10.3390/su13010027 ◽

2020 ◽

Vol 13 (1) ◽

pp. 27

Author(s):

Hatem Mahmoud ◽

Ayman Ragab

Keyword(s):

Climate Change ◽

Heat Stress ◽

Thermal Efficiency ◽

Energy Demand ◽

Building Blocks ◽

Climate Projections ◽

Climate Change Scenarios ◽

Urban Geometry ◽

Outdoor Spaces ◽

The Impact

The density of building blocks and insufficient greenery in cities tend to contribute dramatically not only to increased heat stress in the built environment but also to higher energy demand for cooling. Urban planners should, therefore, be conscious of their responsibility to reduce energy usage of buildings along with improving outdoor thermal efficiency. This study examines the impact of numerous proposed urban geometry cases on the thermal efficiency of outer spaces as well as the energy consumption of adjacent buildings under various climate change scenarios as representative concentration pathways (RCP) 4.5 and 8.5 climate projections for New Aswan city in 2035. The investigation was performed at one of the most underutilized outdoor spaces on the new campus of Aswan University in New Aswan city. The potential reduction of heat stress was investigated so as to improve the thermal comfort of the investigated outdoor spaces, as well as energy savings based on the proposed strategies. Accordingly, the most appropriate scenario to be adopted to cope with the inevitable climate change was identified. The proposed scenarios were divided into four categories of parameters. In the first category, shelters partially (25–50% and 75%) covering the streets were used. The second category proposed dividing the space parallel or perpendicular to the existing buildings. The third category was a hybrid scenario of the first and second categories. In the fourth category, a green cover of grass was added. A coupling evaluation was applied utilizing ENVI-met v4.2 and Design-Builder v4.5 to measure and improve the thermal efficiency of the outdoor space and reduce the cooling energy. The results demonstrated that it is better to cover outdoor spaces with 50% of the overall area than transform outdoor spaces into canyons.

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Potential Impacts of Future Climate Change Scenarios on Ground Subsidence

Water ◽

10.3390/w12010219 ◽

2020 ◽

Vol 12 (1) ◽

pp. 219 ◽

Cited By ~ 2

Author(s):

Antonio-Juan Collados-Lara ◽

David Pulido-Velazquez ◽

Rosa María Mateos ◽

Pablo Ezquerro

Keyword(s):

Climate Change ◽

Land Subsidence ◽

Ground Subsidence ◽

Lower Percentage ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Fine Grained ◽

Fine Grained Material ◽

The Impact

In this work, we developed a new method to assess the impact of climate change (CC) scenarios on land subsidence related to groundwater level depletion in detrital aquifers. The main goal of this work was to propose a parsimonious approach that could be applied for any case study. We also evaluated the methodology in a case study, the Vega de Granada aquifer (southern Spain). Historical subsidence rates were estimated using remote sensing techniques (differential interferometric synthetic aperture radar, DInSAR). Local CC scenarios were generated by applying a bias correction approach. An equifeasible ensemble of the generated projections from different climatic models was also proposed. A simple water balance approach was applied to assess CC impacts on lumped global drawdowns due to future potential rainfall recharge and pumping. CC impacts were propagated to drawdowns within piezometers by applying the global delta change observed with the lumped assessment. Regression models were employed to estimate the impacts of these drawdowns in terms of land subsidence, as well as to analyze the influence of the fine-grained material in the aquifer. The results showed that a more linear behavior was observed for the cases with lower percentage of fine-grained material. The mean increase of the maximum subsidence rates in the considered wells for the future horizon (2016–2045) and the Representative Concentration Pathway (RCP) scenario 8.5 was 54%. The main advantage of the proposed method is its applicability in cases with limited information. It is also appropriate for the study of wide areas to identify potential hot spots where more exhaustive analyses should be performed. The method will allow sustainable adaptation strategies in vulnerable areas during drought-critical periods to be assessed.

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Impact of an accelerated melting of Greenland on malaria distribution over Africa

Nature Communications ◽

10.1038/s41467-021-24134-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Alizée Chemison ◽

Gilles Ramstein ◽

Adrian M. Tompkins ◽

Dimitri Defrance ◽

Guigone Camus ◽

...

Keyword(s):

Climate Change ◽

Malaria Transmission ◽

Ice Sheet ◽

Transmission Risk ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Climate Change Risk ◽

System A ◽

Climate Simulations ◽

The Impact

AbstractStudies about the impact of future climate change on diseases have mostly focused on standard Representative Concentration Pathway climate change scenarios. These scenarios do not account for the non-linear dynamics of the climate system. A rapid ice-sheet melting could occur, impacting climate and consequently societies. Here, we investigate the additional impact of a rapid ice-sheet melting of Greenland on climate and malaria transmission in Africa using several malaria models driven by Institute Pierre Simon Laplace climate simulations. Results reveal that our melting scenario could moderate the simulated increase in malaria risk over East Africa, due to cooling and drying effects, cause a largest decrease in malaria transmission risk over West Africa and drive malaria emergence in southern Africa associated with a significant southward shift of the African rain-belt. We argue that the effect of such ice-sheet melting should be investigated further in future public health and agriculture climate change risk assessments.

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