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The risk of flooding due to runoff is a major concern in many areas around the globe and especially in Romania. In the latest years river flooding and accompanying landslides, occurred quit frequently in Romania, some of which isolated, others-affecting wide areas of the country’s territory.

The main objective of the NATO SfP project “Monitoring of extreme flood events in Romania and Hungary using EO data” is to improve the existing local operational flood hazard assessment and monitoring using the functional facilities supplied by the GIS info-layers, combined with Earth Observation (EO) data-derived information, Digital Elevation Models (DEM) and hydrological modeling. The study area is situated in the Crisul Alb - Crisul Negru - Kőrős transboundary basin, crossing the Romanian — Hungarian border.

The orbital remote sensing can provide necessary information for flood hazard and vulnerability assessment and mapping, which are directly used in the decision - making process. The EO data-derived information of the land cover/land use is important because it makes possible periodical updating and comparisons, and thus contribute to characterize the human presence and to provide elements on the vulnerability aspects, as well as the evaluation of the impact of the flooding. In order to obtain high-level thematic products the data extracted from the satellite images must be integrated with other geo-information data (topographical, pedological, meteorological data) and hydrologic/hydraulic models outputs.

The paper presents the specific methods developed for deriving satellite-based applications and products useful for flood disaster assessment and hazard reduction. An important contribution of EO derived information in the topic of managing flooding connected phenomena could be envisaged at the level of mapping aspects. Using the optical and microwave data supplied by the new satellite sensors (U.S. DMSP/Quikscat, RADARSAT, LANDSAT-7/TM, EOS-AM “TERRA”/MODIS and ASTER) different products like accurate updated digital maps of the hydrographical network and land cover/land use, mask of flooded areas, multi-temporal maps of the flood dynamics, hazard maps with the extent of the flooded areas and the affected zones, etc. have been obtained. These results, at different spatial scales, include synthesis maps easy to access and interpret, adequate to be combined with other information layouts resulted from the GIS database and to ingest rainfall-runoff models outputs.

The presented applications will contribute to preventive consideration of the extreme flood events by planning more judiciously land-use development, by elaborating plans for food mitigation, including infrastructure construction in the flood-prone areas and by optimization of the flood - related spatial information distribution facilities to end — users.

Informal settlements have been part of the South African landscape as far back as the late 1800s. However, in the post-apartheid era, they have increasingly come under the spot light as a media concern. Housing shortages, service delivery, political tension, violence and crime, poverty and the high environmental and health risks are just some of what these settlements have to face. The problem is growing in many urban centres as inmigration continues and exacerbates the problems. In the case of Cape Town (main study context), an estimated 48 000 people are migrating into the City annually (CCC, 2004). Last year alone (2003) the City of Cape Town had a backlog of 240 000 houses (DiMP, 2004) and this year it has increased to 302 000 (CCC, 2004). Besides the huge backlog which the city faces, these areas have become the environments for accumulating disaster risk which result in repeat events that destroy the existing infrastructure and leave many people destitute and homeless. The causes for these disaster occurrences are very under researched and understanding of the complexity is just starting. The data collected shows a 120% increase in fire incidents in the last four years, as well as the fact that the frequencies of small events and the severity of disaster events are increasing disproportionately to the intensity of the hazard (MANDISA, 2004). This fact alone forms the basis of this study which investigation the relationship between settlement density and densification and the increasing patterns of fire severity over time. For this purpose two settlements, namely Imizamo Yethu (Hout Bay) and Joe Slovo (Cape Town Metropol) have been chosen.

Upgrading the infrastructure has, up until recently, been how many local authorities have dealt with informal settlements. They have started realising that the structural upgrading method used to counter the vulnerability of the community only partly solves the problem of fires. Weak community unity, limited awareness of risk, inappropriate behaviour, and irresponsible tenancy by landlords need to be addressed in parallel with structural upgrades (DiMP, 2004). GIS is the main tool used in this study to examine the relationship between dwelling density and informal settlement fires. Its main functionality revolves around analysing certain environments spatially and representing structural factors, however does not currently include non-structural mapping tools. This study will show that the socio-political and economic dynamics in informal settlements, which play an important role in the fire severity and community risk, also needs to be included when undertaking any comprehensive disaster risk assessment. The challenge posed by the complex nature of risk in informal settlements in the South African urban landscape, underlines the need for a holistic and integrated approach to GIS and Disaster Management.

Flash floods strike quickly and in most cases without warning. They are usually observed before any warning can be issued and usually persons and property have been affected before the warning reaches them. Such are the conditions prevalent in Malaysia’s extreme monsoon weather that occasionally causes floods and results in the extensive damage to property and sometimes loss of lives. Over the years variously hydrological and structural engineering measures have been implemented for flood monitoring and forecasting. These measures have only yielded limited success as may be seen in the recurring flood situation. Yearly financial and property loss estimates have increased and an estimated cost of over 2.5 billion RM is projected for the year 2004 according to sources from the drainage and irrigation department of Malaysia. It has thus become apparent that Malaysia institutes an effective operational flood forecasting to arrest the persisting flood problem.

In this paper we will expound on current flood management and forecasting system being implemented in the country, particularly the Klang Valley that includes Kuala Lumpur where there has been tremendous urban growth and development in the last one and half decades. The paper further discusses where current flood management systems have been lacking in the absence of real-time hydro-meteorological forecasts. Where as hydrodynamic simulations and structural control measures have been emphasized in many flood management systems in Malaysia, the integration of real-time hydro-meteorological forecasts have been conspicuously absent, rendering most in-situ flood forecasts and early warnings ineffective in address the flood problem in the country.

Malaysia is a tropical country that lies along the path of the northeast and southwest monsoon. Although satellite image based NWP have proved useful for the tropical and equatorial regions of the world in flood forecasting, they have yet to be applied in Malaysia. Observations have generally shown heavy cumulonimbus clouds formation and thunderstorms precede the usual heavy monsoon rains that cause floods in the region. This makes quantitative precipitation forecast a must be input to any flood early warning design. Numerous empirical studies have determined that cloud top temperatures less that 235k in the tropics are generally expected to produce convective rainfall at the rate of 3mm/hr. In this study we thus investigate monsoon cloud formation that has the propensity to precipitate using NOAA-AVHRR data for real-time operational flood early warning in Malaysia. The AVHRR data has been preferred for its relatively high temporal resolution of at most 6/hours, its easy acquisition and cost effectiveness and its ability for automated geometric rectification when compared to GEOS and GMS data.

Cloud cover and types are processed using cloud indexing and pattern recognition techniques on the AVHRR data. The cloud indexing technique was initially developed for NOAA but was later also adapted for Geostationary satellite images. The technique assigns rainfall levels to each cloud type identifies in an image based on the relationship between cold and bright clouds top temperature and the high probability of precipitation. We discuss how visible (VIS) and infrared (IR) techniques are applied to bi-spectral cloud classification and rain areas are determined by classifying pixel clusters in the VIS/IR histogram. Precipitation probability is evaluated based on the relationship between cold and brightness temperature of clouds. The near infrared (NIR) and infrared (IR) channels 3, 4, and 5 of the data are processed for temperature and brightness. Cold clouds with temperature below 235k threshold value are taken as indication of rain. Rainfall is estimated based on the assumption that every cloud pixel has a constant unit rain-rate of 3mm, which is appropriate for tropical precipitation over 2.5° × 2.5° areas around the equator. The paper finally discusses current developments in “nowcasting” that utilizes latest satellite observations together with numerical weather prediction models and how this system can be adapted to the needs of very short term forecast for flood early warnings in Malaysia.

In Hungary flood disasters are the major natural hazard as a consequence of lowland topographic conditions. Due to both structural and nonstructural mitigation measures from the mid 19 century, like building dikes and developing adequate warning system, no loss of life was reported since the 1950’s. Nevertheless the value of damage to human property in flood-prone areas may reach millions of euros each year throughout the country. Flood forecast is performed by the national hydrological institute, and warning is transmitted to the local hydrological authorities about the forthcoming disaster. Disaster response measures are based on conventional hydrological information and action plans are developed with traditional methods. The latest technology of GIS and remote sensing is not yet tested in the country to support the spatial information need of disaster response.

The aim of our investigation was to test impact modeling using mostly freely available spatial data. This may ensure feasibility in a case of a future flood catastrophe in various geographic location. The decision of using non-commercial data was further based on the experience that data acquisition from dissimilar sources like local authorizes and the military mapping agency may last weeks or months and was found not suitable for rapid results.

Investigation was based on the recent flood disaster event in the Northern part of the country in the summer of 2004.

To analyze the elements possibly being damaged by the flood, the extent of the inundation was calculated. Flood simulation was executed using digital elevation model of the remotely sensed SRTM radar data and hydrological data from the Hungarian Water Resources Research Centre (VITUKI). Modeled flood extent was serving the basis of spatial analysis of the disaster impact. Settlements hit by the flood disaster were queried. Moreover the condition of flooded road and railway network was analyzed to support route planning of mitigation efforts.

Results of this investigation should help to speed up decision making processes during future disaster events. Moreover should help to reduce property damages and suffering of flood victims.

Risk assessment is a complex issue aiming at evaluation of different aspects of disaster damages. Traditionally, risk analysis relies on mathematical models to establish the likelihood of a given event occurring with a given degree of intensity in a given site. The major limitation of this type of approach is the fact that the field of risk necessarily entails uncertainty and it is not therefore always possible to make realistic hypotheses about possible future scenarios.

Therefore, a new approach is required, that can take into account social, economic, cultural, and political aspects that are not generally considered in traditional assessment methods, but that serve to define the capacity of response of a territorial system to a disaster.

In this paper we present a new approach, according to which the assessment process breaks down the principal goals into a hierarchy of lower level sub-goals. Each element of the hierarchy is assigned a local weight that evaluates the importance of that element not in overall terms (i.e. referred to the principal goal), but only in relation to the supra-ordinate element with which it is compared.

The approach is tested in a case study estimating the risk of flooding in the Municipality of Monopoli, Italy.

The eastern Africa sub-region is an expansive land-mass, more than 6 million km comprising about 9 countries. Ecologically and environmentally the area is highly precarious, more than 65% of the sub-region being classifiable as semi-arid or arid. Some of the countries in the sub-region experience real desert like conditions with less than 250 mm annual rainfall. The sub-region experiences very frequent droughts, while rainfall distribution and intensity vary considerably, spatially and temporally. Frequent drought-related disasters include famines as a result of crop failures and lack of grazing and browse. The famines often result into human calamities such as hunger, starvation, malnutrition, mass migration of populations and in many cases death. These negative impacts of famine, resulting from environmental factors, are often compounded by several socio-economic and political factors that have over the years impacted negatively on the general production of the area. Many of these calamities due to their slow onset are ignored and often realised late, many times when their negative impacts and toll on the population have reached devastating levels. Part of the reason is lack of or inadequate Early Warning Systems (EWS) for monitoring environmental conditions as well as crop yields. This paper gives an overview of some the often ignored disasters suggesting some disaster management mechanisms that need to put into consideration in addressing and managing such calamities.

This paper describes the development of an Arcview GIS extension namely SFlood.avx to integrate the SFlood hydraulic and sediment transport model (modified version of HEC-6 model) within ArcView GIS environment. The extension was written in an Avenue script language and Dialog Designer with a series of ‘’ options. The flood risk model was tested using the hydraulic and hydrological data from Pari River catchment area in Malaysia. The required sediment input parameters were obtained from field sampling. Sflood.avx has the capability of analyzing the computed water surface profiles generated from SFlood hydraulic model and producing a related flood risk map for Pari River in Arc- View GIS. The user-friendly menu Graphic User Interface guides the user to understand, visualize, build query, conduct repetitious and multiple analytical tasks with SFlood model outputs. The results of this study clearly show that GIS provides an effective environment for flood risk analysis and mapping.

This paper presents the efforts by Boğaziçi University, Kandilli Observatory and Earthquake Research Institute (BU-KOERI), Istanbul Community Impact Project in Istanbul, Turkey in piloting three innovative uses of geospatial information technology for community-participation in disaster mitigation. 1) provided volunteers with skills and tools for identification of seismic risks and response assets in their neighborhoods. Field data collection volunteers used low-cost hand-held computers and data compiled was fed into a geospatial database accessible over the Internet. Interactive thematic maps enabled discussion of mitigation measures and action alternatives. This pilot evolved into a proposal for sustained implementation with local fire stations. 2) involved collaboration between the Istanbul Community Impact Project and the Istanbul Education Directorate. School Basic Disaster Awareness instructors reported on dissemination of training using a web-based data entry application. The data was used to create a series of interactive Web-based thematic maps showing the geographic reach of the training program with hot links which allow the public to drill down to see local contact information. 3) was designed to track school-bus routes in Istanbul, in order to stimulate contingency planning for commute-time emergencies when 400,000 students travel an average of 45 minutes each way on 20,000 service buses. Global Positioning System (GPS) data loggers were used to determine service bus routes displayed on printed maps highlighting nearest schools along the route. It is proposed that bus-drivers, parents and school managers be issued route maps with nearest schools that could serve as both meeting places and shelters. The system is designed to be in synchrony with the Istanbul Earthquake Early Warning and Rapid Response System housed at BU-KOERI.