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The continuous increase in damages to flood disasters globally has informed the need to assess vulnerability of built-up exposures for future flood risk reduction. The aim of this paper is to understand the contributions of some important variables in flood damage processes and develop loss functions for global building types, for the estimation of flood economic damages in Chao Phraya river basin, Thailand. We obtained empirical damage data (118 samples) through questionnaire survey in the study area for analysis. Using multiple linear regressions analysis, we generated loss functions for the aggregated residential building incorporating multiple damage factors. Further, disaggregated vulnerability curves (as a function of water depth) were established using logarithm function for three global building types in the study area. Results showed that, under flood condition in the study area, water depths and building age are very important damage factors, other variables are also emphasized. The loss models show maximum predicted vulnerability indices of 0.36, 0.30 and 0.10 for wooden, concrete frame and unreinforced masonry, and reinforced concrete moment frame, respectively. These functions can be used for modeling flood damage, for future disaster risk reduction and for risk comparison across countries. [ABSTRACT FROM AUTHOR]

Agricultural terraces are the most evident landscape imprints of traditional knowledge on soil conservation and water management globally. This article focuses on the Ifugao Rice Terraces (IRT) of the Philippines, a sustainable agroecosystem built on the harmonious relationship between indigenous people and their local environment. We elucidate how the rice terraces influence the hydrologic response at a small catchment scale through detailed field monitoring and physically based mathematical modeling. We also explore the consequences of socioeconomic pressures manifested through land-use change. Our results quantitatively reaffirm the effectiveness of well-maintained agricultural terraces in regulating water resources by enhancing groundwater recharge. Meanwhile land-cover change induced by terrace abandonment was shown to lead to an overall decrease in water resource availability. [ABSTRACT FROM AUTHOR]

An automated version of the weather type classification scheme was performed over Japan to characterize daily circulation conditions. A daily gridded field of mean sea-level pressure (MSLP) from the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis dataset (ERA-interim) and the THORPEX Interactive Grand Global Ensemble (TIGGE) daily forecast dataset were used. The weather type is advantageous as it provides an opportunity to improve global rainfall prediction by refining statistical bias correction. We distinguished 11 weather types: anticyclone, cyclone, hybrid and eight purely wind directions. The results indicate that the main weather types contributing to the total volume of rainfall are cyclone, hybrid, purely westerly and northwest winds. A gamma-based bias correction decreases the global rainfall forecast root mean square by 10%, while specific weather type gamma bias correction accounts for 5–10% root mean square error reduction, with a total decrease of errors up to a maximum of 20%. Both global and weather type bias corrections improve the extreme dependency scores (EDS), but for different extreme rainfall thresholds. The study advocates the use of weather type bias-correction methods for extreme event rainfall intensity corrections higher than 100 mm/d.EDITORA. CastellarinASSOCIATE EDITORA. Jain [ABSTRACT FROM PUBLISHER]

This article evaluates the equity performance of bulk water allocation as an irrigation management strategy in the Mahaweli Ganga Development Project, Sri Lanka. Through semi-structured interviews with farmers and irrigation officials, the study collected local perceptions using seven indicators: water rights; decision-making process; contribution of resources for irrigation maintenance; water allocation rules; actual water distribution; information sharing; and conflict resolution. The results highlight gaps in the institution such as the need to enhance the water rights of landless farmers, further encourage crop diversification, increase transparency in decision making, instil a risk-management approach, and strengthen accountability. [ABSTRACT FROM PUBLISHER]

This paper introduces an integrated model for flood loss estimation in a river basin. The model is the combination of a physically based distributed hydrologic model and a distributed flood loss estimation model. The hydrologic model considers major processes of the water cycle through physically based governing equations, which are solved to simulate the propagation of water in each of these processes. It is designed to consider the man-made flood control structures, such as river embankments, retarding basins, etc. which affect flooding characteristics. The loss estimation model is formulated based on stage-damage relationships between different flood inundation parameters and landuse features. It calculates the economic loss to different landuse features based on the simulated flood parameters obtained from the hydrologic model for any flood event.A case study illustrates the real world application of the integrated model to a medium size river basin in Japan, which is frequently affected by floods. The simulated river discharge and surface inundation by the flood model show good agreement with the observations. Urban flood loss simulated by the loss estimation model with the simulated flood parameters agrees with the estimated damage using post flood surveyed parameters. [Copyright &y& Elsevier]

Wang, Y.; He, B.; Herath, S.; Basnayake, S. and Huang, W., 2014. Climate change scenarios analysis in coastal region of Thailand. The impact of climate change is estimated to be particularly severe in many developing countries, including the coastal zones prone to flooding and drought. As a coastal region, Thailand has been affected by climate change significantly in terms of temperature and rainfall distribution change. In this study, a downscaling study was carried out to identify some climate-related planning parameters for the representative cities in Thailand using the regional climate model. Results indicated that in the study area around the Hat Yai the near future atmosphere temperature will increase about 1 °C to 1.5 °C compared to the present condition. The minimum annual temperature will increase about 0.8 degree from 23 °C to 23.8 °C. It is ranging between 20.8 °C-25 °C. The maximum annual temperature in Hat Yai will increase about 1 degree from 32.6 °C to 33.6 °C. The mean annual temperature will increase about 1 degree from 27.8 °C to 28.8 °C. The temperature will increase largely in summer and rainy season in the future. The near future rainfall is projected to increase in most of seasons, especially during the rainy season which will bring more risk for flood disaster. Furthermore, rainfall pattern and distribution will be also changed in the near future in Songkhla, with more rain to be expected in rainy season. [ABSTRACT FROM AUTHOR]

Highlights: [•] Rice cultivars differ (−17% to +7%) in yield response to elevated CO2 (+100ppm) and temperature (+1°C). [•] CERES-Rice must be re-parameterized to accurately simulate crop yield under climate change scenarios. [•] Overall yield of current modern cultivars will decline under future climates. [•] Yield was maintained in the cultivar ‘Badshabhog’ with long duration, long leaves, and short grains. [ABSTRACT FROM AUTHOR]

The projected adverse impact of climate change on food grain production of tropical and subtropical latitudes necessitates the development of suitable agro-adaptations. We used open top chamber (OTC) experimental facility and simulation analysis to study the effect of elevated [CO2] with varying nutrients management on rice grain yield and to evaluate planting time adjustment as adaptation to climate change. The OTC experiments with ambient [CO2] level ([CO2] ~390 ppm) and elevated [CO2] (25% higher than the ambient) using cultivar 'Swarna sub1 (140–145 days)' were conducted during wet season of the years 2011 and 2012 at West Medinipur, India. Using CERES model, we simulated rice grain yield for future climate scenario (A1B) during the years 2020 (2010–2039) and 2080 (2071–2099) at four selected locations of the subtropical India. The elevated [CO2] in OTC increased panicle number, but decreased filled grain number per panicle, 1000-grain weight and grain yield. The increasing [CO2] had smaller adverse impact for integrated nutrients management as compared with chemical fertiliser. The model simulated grain yield reduction of 6.1−13.0% during 2020 and 14.4 −25.0% during 2080 with rising temperature 1.6 and 4.6°C, respectively, compared with the base period (1961–1990). Early planting during 25 June to 25 July received closure favourable temperature and rainfall during the crop growing period, hence had better adaptation to the climate change. Increasing dose of integrated nutrients and early planting is expected to minimise the adverse impact of climate change on rice production of the subtropical India. A field experiment was conducted to evaluate nutrients management and plating time as adaptations to climate change for wet season rice production under rainfed ecosystem of subtropical India. A well validated location specific management option for climate change adaptation in rice production system is lacking. Keeping this in mind, we conducted this experiment and we observed that, increasing dose of integrated nutrients and early planting is expected to minimise the adverse impact of climate change on rice production of the subtropical India. [ABSTRACT FROM AUTHOR]