Ensemble flood risk assessment in Europe under high end climate scenarios

AbstractAt the current rate of global warming, the target of limiting it within 2 degrees by the end of the century seems more and more unrealistic. Policymakers, businesses and organizations leading international negotiations urge the scientific community to provide realistic and accurate assessments of the possible consequences of so called “high end” climate scenarios.This study illustrates a novel procedure to assess the future flood risk in Europe under high levels of warming. It combines ensemble projections of extreme streamflow for the current century based on EURO-CORDEX RCP 8.5 climate scenarios with recent advances in European flood hazard mapping. Further novelties include a threshold-based evaluation of extreme event magnitude and frequency, an alternative method to removing bias in climate projections, the latest pan-European exposure maps, and an improved flood vulnerability estimation.Estimates of population affected and direct flood damages indicate that by the end of the century the socio-economic impact of river floods in Europe is projected to increase by an average 220% due to climate change only. When coherent socio-economic development pathways are included in the assessment, central estimates of population annually affected by floods range between 500,000 and 640,000 in 2050, and between 540,000 and 950,000 in 2080, as compared to 216,000 in the current climate. A larger range is foreseen in the annual flood damage, currently of 5.3 B€, which is projected to rise at 20–40 B€ in 2050 and 30–100 B€ in 2080, depending on the future economic growth

Analysis of flash flood scenarios in an urbanized catchment using a two-dimensional hydraulic model

Abstract. In Italy, growing urbanization is leading to a higher risk of flooding of small water courses, especially in steep catchments of limited area, where severe flash flood events can occur. The assessment of flash flood hazard requires new modelling tools that can reproduce both the rainfall–runoff processes in the catchment, and the flow processes in the drainage network. In this paper we propose the use of a simple two-dimensional hydraulic model for analysing a flood scenario in a small valley within the urban area of the city of Bologna, Italy. Historically this area has been prone to severe flood events, the most recent of which occurred in 1955 and 1932. Since then there has been a significant increase in urbanization of the lower portion of the catchment, while the natural stream bed has been partially replaced by a culvert. The two-dimensional hydraulic model was therefore applied at catchment scale, in order to simulate the possible effects of historical scenarios in the present catchment configuration. Rainfall and runoff data measured during recent rainfall events were used to calibrate model parameters. Model results show that the current culvert section would be insufficient to drain the runoff produced by intense rainfall events, with potential inundation of surrounding urban areas

PESETA III - Task 7: River Floods

In Europe around 216,000 people are exposed each year to river flooding and annual flood damage amounts to €5.3 billion. In most regions of Europe we see an increase of flood risk due to global warming. Under a 2°C global warming scenario and considering current socio-economic conditions, flood impacts could more than double, with around 525,000 people annually exposed to floods and €12.5 billion of expected annual losses. Under the RCP8.5 pathway 2°C will occur in the early 2040s, hence impacts on present society under near term (2021-2050) climate conditions are very close to those under a 2°C warming scenario. Longer term climate conditions (2071-2100) under a RCP8.5 scenario imposed on present society, on the other hand, could result in around 717,000 people annually exposed to floods while direct flood damages could see a more than three-fold increase with respect to current conditions, reaching €17.5 billion of average annual losses.JRC.E.1-Disaster Risk Managemen

Development and evaluation of a framework for global flood hazard mapping

AbstractNowadays, the development of high-resolution flood hazard models have become feasible at continental and global scale, and their application in developing countries and data-scarce regions can be extremely helpful to increase preparedness of population and reduce catastrophic impacts.The present work describes the development of a novel procedure for global flood hazard mapping, based on the most recent advances in large scale flood modelling. We derive a long-term dataset of daily river discharges from the hydrological simulations of the Global Flood Awareness System (GloFAS). Streamflow data is downscaled on a high resolution river network and processed to provide the input for local flood inundation simulations, performed with a two-dimensional hydrodynamic model. All flood-prone areas identified along the river network are then merged to create continental flood hazard maps for different return periods at 30′′ resolution. We evaluate the performance of our methodology in several river basins across the globe by comparing simulated flood maps with both official hazard maps and a mosaic of flooded areas detected from satellite images. The evaluation procedure also includes comparisons with the results of other large scale flood models. We further investigate the sensitivity of the flood modelling framework to several parameters and modelling approaches and identify strengths, limitations and possible improvements of the methodology

A near real-time procedure for flood hazard mapping and risk assessment in Europe

The availability of a real-time operational system for mapping flood hazard and assessing potential consequences might be extremely useful to help emergency response and management and to mitigate the impact of large flood events. This work describes the development of an experimental procedure for rapid flood risk assessment within the European Flood Awareness System (EFAS), which since 2012 provides operational flood predictions for the major European rivers as part of the Copernicus Emergency Management Services. The hydro-meteorological data set available in EFAS is used to derive long-term streamflow simulations and design flood hydrographs in a wide number of locations, covering all the major European river network. Flood hydrographs are then used as input to a hydrodynamic 2D model to create a high resolution dataset of areas at risk of flooding for different return periods. Whenever a flood event is forecasted in EFAS, the flood maps of the river network sections potentially involved are merged together, based on the estimated magnitude of the event. In order to take into account the different flood forecasts available in EFAS, different combinations of flood hazard maps may be produced, to highlight the possible range of uncertainty in predictions. The merged flood maps can be combined with the available spatial information about land use, population, urban areas and infrastructures, to assess the potential impact of the forecasted flood event in terms of economic damage, affected population, major infrastructures and cities. A preliminary version of the procedure has been successfully tested in reproducing flooded areas and impacts in the recent floods in Bosnia-Herzegovina, Croatia and Serbia. Moreover, the reduced computational times are compatible with near real-time applications, even in case of multiple flood events affecting several countries. Currently, the integration of the procedure within EFAS for operational use is being tested.JRC.H.7-Climate Risk Managemen

Linking Early Warning Systems with Rapid Mapping - Procedure for pre-tasking of satellites for disaster impact mapping

This is a technical document describing the step-by-step procedure for pre-tasking of satellites for disaster impact mapping in the frame of the Copernicus Emergency Management Service (CEMS). Pre-tasking is done following alerts for upcoming disasters issued by early warning systems (in this case by the European Flood Awareness System) which are either operated under CEMS or under other frameworks. Disaster impact mapping is performed under Rapid Mapping, the 24/7/365 on-demand service of CEMS. The procedure has been integrated into the standard operating procedures of the Emergency Response Coordination Center of DG ECHO.JRC.E.1-Disaster Risk Managemen

Transition to turbulence in a heated non-Newtonian pipe flow

A simplified mono-dimensional model for investigating the transition to turbulence in nonisothermal and non-Newtonian pipe flows is proposed. The flow stability is analyzed within the framework of such a model, showing that uniformly heating the pipe wall leads to an earlier transition to turbulence, while differentially heating the pipe wall produces a stabilizing effect. For power-law fluids, we also demonstrate that an increase in the power-law index, i.e., passing from shear-thinning to shear-thickening fluids, leads to a stabilization of the system

Ecosystem services accounting - Part II Pilot accounts for crop and timber provision, global climate regulation and flood control

The Knowledge Innovation Project on an Integrated system of Natural Capital and ecosystem services Accounting (KIP INCA) aims to develop a set of experimental accounts at the EU level, following the United Nations System of Environmental-Economic Accounting - Experimental Ecosystem Accounts (SEEA EEA). The application of the SEEA EEA framework is useful to illustrate ecosystem accounts with clear examples, to further develop the methodology outlined in the United Nations Technical Recommendations, and to give guidance for Natural Capital Accounting. This report assesses and accounts for four ecosystem services (ES): crop provision, timber provision, global climate regulation, and flood control. The methodology applied for the accounts of each ecosystem service depends on the nature of the service and on data availability. Crop provision account is based on official statistics on yield production. Here, we combine yield statistics with a novel approach to disentangle the yield generated by the ecosystem from what is generated by the human inputs (i.e., planting, irrigation, chemical products). Timber provision account follows a similar rationale, but the data to assess the ecosystem contribution is derived from economic aggregates. The global climate regulation account uses carbon sequestration as a proxy. The account is built on the ecosystem CO2 uptake reported in the Land Use, Land-Use Change and Forestry (LULUCF) inventories at country level. Copernicus data (Dry Matter Productivity) have been also used to map CO2 uptake by forest (the only ecosystem type acting across countries and over time, as reported in LULUCF inventories). Maps of CO2 uptake are useful to make comparisons with other ecosystem services in a later stage of the project, in particular to assess synergies and trade-offs. Complementarily, we also provide a thematic account for soil organic carbon based on data from Land Use/Cover Area frame Survey (LUCAS). However, this information is considered as an asset account in physical terms because it quantifies organic carbon stocks into the soil, and not flows. The valuation method used for crop and timber provision is based on market values and for global climate regulation is a proxy of market values. The account of flood control by ecosystems is the only service in this report based on biophysical modelling. Different components of the ecosystem service have been quantified: ES potential, ES demand, actual flow (or service use), and unmet demand. The actual flow, quantified as the hectares of demand benefiting from ecosystems in a given year, is also translated into monetary terms using as valuation technique the avoided damage cost. Results of the accounts at the EU level for the first period assessed (year 2000-2006) show a decrease of the monetary value of the services for crop (-5%) and timber provision (-2%), and a very slight increase for global climate regulation (+0.4%). The account for flood control was not available for the first period because of the lack of data, which is a limiting factor for a regularly updated ecosystem service account. In contrast, for the second period assessed (year 2006-2012), all four service show an increase in their monetary value: +34% for crop provision, +2% for timber provision, and +1.3% for global climate regulation and +1.14% for flood control. The use of spatially explicit models for the account of flood control provides very useful information to understand the drivers of changes in the value of this service. The increase of artificial areas benefiting from ecosystems controlling floods increases the value of flood control by ecosystems; however, its value per unit of economic asset decreases. This, together with an increase of the demand not covered by the ecosystem for artificial areas (i.e., unmet demand), show that there is a negative trend in the role of natural capital covering the need for flood control in these areas. So far, six ecosystem service accounts have been developed: crop and timber provision, crop pollination, global climate regulation, flood control and nature-based recreation. The supply table at the EU level for all these six ecosystem services in 2012 shows woodland and forest as the ecosystem type with the highest absolute (~70 billion euro) and relative values (~44 thousand euro/km2). In absolute terms, cropland appears as the second most important ecosystem given its large extent at the EU level; however, when it comes to relative values (value per square kilometre) cropland is among the ecosystem services with the lowest value. Complementary, the use table shows households, followed by the agriculture sector, as the main beneficiaries of these ecosystem services; receiving an annual monetary flow of about ~62 billion euro and ~25 billion euro, respectively. The experimental accounts shown for these ecosystem services, in a consistent way with the SEEA EEA, are useful to further develop the methodology applied for ecosystem services accounts. We also discuss about the advantaged and disadvantaged of the different data sources and methods used. Future releases of pilot ecosystem services accounts will include water purification, habitat maintenance and soil erosion control. The final integrated assessment will be carried out at the end of the KIP INCA project, when a more comprehensive list of ecosystem services become available. The integration of ecosystem services accounts will be useful to make trade-offs in decision making more transparent, inform efficient use of resources, enhance resilience and sustainability, and avoid unintended negative consequences of policy actions.JRC.D.3-Land Resource

West Nile virus transmission. results from the integrated surveillance system in Italy, 2008 to 2015

IIn Italy a national Plan for the surveillance of imported and autochthonous human vector-borne diseases (chikungunya, dengue, Zika virus disease and West Nile virus (WNV) disease) that integrates human and veterinary (animals and vectors) surveillance, is issued and revised annually according with the observed epidemiological changes. Here we describe results of the WNV integrated veterinary and human surveillance systems in Italy from 2008 to 2015. A real time data exchange protocol is in place between the surveillance systems to rapidly identify occurrence of human and animal cases and to define and update the map of affected areas i.e. provinces during the vector activity period from June to October. WNV continues to cause severe illnesses in Italy during every transmission season, albeit cases are sporadic and the epidemiology varies by virus lineage and geographic area. The integration of surveillance activities and a multidisciplinary approach made it possible and have been fundamental in supporting implementation of and/or strengthening preventive measures aimed at reducing the risk of transmission of WNV trough blood, tissues and organ donation and to implementing further measures for vector control

Mosquito, Bird and Human Surveillance of West Nile and Usutu Viruses in Emilia-Romagna Region (Italy) in 2010

<div><h3>Background</h3><p>In 2008, after the first West Nile virus (WNV) detection in the Emilia-Romagna region, a surveillance system, including mosquito- and bird-based surveillance, was established to evaluate the virus presence. Surveillance was improved in following years by extending the monitoring to larger areas and increasing the numbers of mosquitoes and birds tested.</p> <h3>Methodology/Principal Findings</h3><p>A network of mosquito traps, evenly distributed and regularly activated, was set up within the surveyed area. A total of 438,558 mosquitoes, grouped in 3,111 pools and 1,276 birds (1,130 actively sampled and 146 from passive surveillance), were tested by biomolecular analysis. The survey detected WNV in 3 <em>Culex pipiens</em> pools while Usutu virus (USUV) was found in 89 <em>Cx. pipiens</em> pools and in 2 <em>Aedes albopictus</em> pools. Two birds were WNV-positive and 12 were USUV-positive. Furthermore, 30 human cases of acute meningoencephalitis, possibly caused by WNV or USUV, were evaluated for both viruses and 1,053 blood bags were tested for WNV, without any positive result.</p> <h3>Conclusions/Significance</h3><p>Despite not finding symptomatic human WNV infections during 2010, the persistence of the virus, probably due to overwintering, was confirmed through viral circulation in mosquitoes and birds, as well as for USUV. In 2010, circulation of the two viruses was lower and more delayed than in 2009, but this decrease was not explained by the relative abundance of <em>Cx. pipiens</em> mosquito, which was greater in 2010. The USUV detection in mosquito species confirms the role of <em>Cx. pipiens</em> as the main vector and the possible involvement of <em>Ae. albopictus</em> in the virus cycle. The effects of meteorological conditions on the presence of USUV-positive mosquito pools were considered finding an association with drought conditions and a wide temperature range. The output produced by the surveillance system demonstrated its usefulness and reliability in terms of planning public health policies.</p> </div