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This study presents the first comprehensive analysis of the seasonal characteristics of raindrop size distribution (DSD) in Metro Manila, Philippines, using two years of measurements (2018–2020) from the PARSIVEL2 disdrometer. Seasonal properties of DSD for both stratiform and convective rain types were examined during the Southwest Monsoon (SWM; June–September), Northeast Monsoon (NEM; October–February), and pre-SWM or Transition period (March–May). Key findings reveal the dominance of small raindrops (<1 mm) during the NEM period, while mid-sized (1–3 mm) to large raindrops (>3 mm) are more prevalent during the SWM and Transition periods. The study highlights notable seasonal differences in DSD at moderate rain rates (5–10 mm hr−1), indicating variations in microphysical processes between stratiform and convective rain. Furthermore, the microphysical properties of convective rain in Metro Manila are found to be influenced by both oceanic and continental convective processes based on their mass-weighted mean diameter and generalized intercept parameter for all the monsoon periods. The DSD-derived dual-polarimetric radar variables are also shown to vary with the monsoon periods. Rainfall estimates using the DSD-derived dual-polarimetric relations statistically outperformed the empirical rainfall retrieval equation currently used by operational weather radars in the Philippines. Additionally, the Gamma shape parameter found in this study aligns with existing rainfall retrieval algorithm assumptions in space-borne radars. This similarity, along with the derived microphysical relations, could provide potential improvements in rainfall retrievals of ground-based and space-borne radars in tropical coastal environments like Metro Manila. • First comprehensive study of seasonal raindrop size distribution in Metro Manila using long-term disdrometer data. • Small raindrops dominate northeast monsoon rainfall; larger drops are more common in transition period and southwest monsoon. • Disdrometer-derived equations for ground and space radars may improve radar rainfall estimates over Metro Manila. [ABSTRACT FROM AUTHOR]

• The first WRF-UCM simulations with AH flux for Metro Manila. • ACM2 PBL scheme perform better than YSU and MYNN2.5 in Manila. • RRTMG scheme is better than Dudhia/RRTM and New Goddard. • Urban areas in Metro Manila are 4 °C warmer than cropland during heat wave events. • AH effect contributes about 10 % to the UHII compared to the urbanization effect. This study aims to assess the performance of Weather Research and Forecasting coupled with the urban canopy model and anthropogenic heat (AH) on extreme heat events and determine the potential effect of urbanization on these extreme heat events in Metro Manila. Simulations with well-represented urban land use capture temperature (Mean Bias is -0.39 °C), especially during nighttime compared to simulations without urban land cover. The simulations with urban areas at night show an increase in sensible (∼75 W m −2) and ground heat fluxes (∼125 W m −2), while a decrease in latent heat flux (∼13 W m −2) compared to simulations without urban areas. Simulations with urban cover have temperatures more than 4 °C in central Metro Manila than simulations with no urban grids. Sensitivity tests with three different planetary boundary layer (PBL) and radiation schemes show that ACM2 performed best, while RRTMG captured distribution. During the heatwaves, the daytime and nocturnal urban heat island intensities (UHIIs) are estimated at 0.75 °C and 2.17 °C, respectively. The AH effect on UHII is more substantial during nighttime and contributes about 10 % to the UHII compared to the urbanization effect. This study may help policymakers identify hotspots in Metro Manila and develop adaptation/mitigation strategies for extreme heat events. [ABSTRACT FROM AUTHOR]

In this study, we describe the chemical and physical characteristics of two air pollution events in the first half of January 2020 in Metro Manila, Philippines, namely the New Year's eve fireworks and the Taal volcano ashfall. During the New Year's eve fireworks, PM 2.5 concentration and most of the chemical components increased three-fold. However, we found disproportionately higher increases for certain metallic components typically used as pyrotechnic propellant and/or colorant for blue, white, and green light: Fe(5-fold), Cr(5-fold), Cu(8-fold), Ni(9-fold), V(10-fold), Ti(11-fold), and Ba(34-fold). These results provide insights for health assessments and legislation related to fireworks emissions. On January 12, 2020, the Taal volcano eruption caused much concern in Metro Manila as visible tephra deposits were observed. There was only a slight increase (8%) in PM 2.5 concentration and its components related to basaltic ash. The low PM 2.5 concentration was mainly due to the inhibited intrusion of ash into the stable nocturnal boundary layer. In addition, the detection of lightning in the plume and umbrella region showed size segregation of ash particles. The WRF-Chem model was able to capture the distribution of both tephra advection and fallout, a first for Taal volcano, making it possible for use in the future ashfall forecasting. [Display omitted] • Two air pollution events on January 2020 in Metro Manila, Philippines were investigated. • High levels of toxic metallic elements were found during New Year's celebratory fireworks. • PM 2.5 deposition from Taal volcano eruption was inhibited by the stable nocturnal boundary layer. • WRF-Chem successfully simulated the size and spatial distribution of the volcanic ash plume. [ABSTRACT FROM AUTHOR]

Abstract: In recent decades, the practice of environmental impact assessment (EIA) in the planning processes of infrastructure projects has created significant awareness on the benefits of environmentally sound and sustainable urban development around the world. In the highly urbanized megacities in the Philippines, like Metro Manila, high priority is given by the national government to structural flood mitigation measures (SFMM) due to the persistently high frequency of flood-related disasters, which are exacerbated by the on-going effects of climate change. EIA thus, should be carefully and effectively executed to maximize the potential benefits of the SFMM. The common practice of EIA in the Philippines is generally qualitative and lacks clear methodology in evaluating multi-criteria systems. Thus, this study proposes the use of the rapid impact assessment matrix (RIAM) technique to provide a method that would systematically and quantitatively evaluate the socio-economic and environmental impacts of planned SFMM in Metro Manila. The RIAM technique was slightly modified to fit the requirements of this study. The scale of impact was determined for each perceived impact, and based on the results, the planned SFMM for Metro Manila will likely bring significant benefits; however, significant negative impacts may also likely occur. The proposed modifications were found to be highly compatible with RIAM, and the results of the RIAM analysis provided a clear view of the impacts associated with the implementation of SFMM projects. This may prove to be valuable in the practice of EIA in the Philippines. [Copyright &y& Elsevier]

Abstract: Urban environments are not considered areas with conservation importance. However greenspaces in cities have been previously identified as areas with significant avian biodiversity. We investigated the distribution and diversity of birds in what are increasingly considered as Metropolitan Manila''s last greenspaces; the University of the Philippines campus, military cemeteries and two government operated parks. Using species–area analysis, abundance and diversity indices, TWINSPAN ordination and logistic regression to determine important landscape features for species presence, we describe the distribution of bird communities and diversity in Metropolitan Manila. Two major bird community groupings were observed. These are the urban exploiters and the urban adaptable with the former occurring in high abundances and the latter in low abundances in greenspaces. The number of built and natural spatial entities determines abundances. Species area analysis suggests that the greenspaces are distinct habitats that preserve faunal uniqueness whereas urbanization tends to decrease diversity. These observations suggest that greenspaces harbor significant avian biodiversity as well as the presence of endemic and threatened species. As the greenspaces possess remnant wetland and wooded habitat we recommend that they be preserved and maintained by ensuring that these habitats are incorporated in any urban development plan. [Copyright &y& Elsevier]

Abstract: Building damage due to a scenario earthquake in Metro Manila, Philippines is estimated based on seismic performance of the buildings evaluated by local experts’ judgments. For the damage estimation, building capacity curves and fragility curve are developed from questionnaire to the local experts of structural engineering. The Delphi method is used to integrate the experts’ opinions. The derived capacity curves are validated by comparing with the result of pushover analysis for typical buildings. Building responses due to simulated ground motions are estimated by the capacity spectrum method. Damage ratios are calculated from the fragility curves and the building responses. Distributions of the damaged buildings are computed by multiplying the damage ratios and the building inventory. The distribution and the amount of the damaged buildings in this study show significant difference from the estimation with the capacity curves of HAZUS, suggesting the importance of evaluation of the region-specific building performance. [Copyright &y& Elsevier]

Abstract: The researcher quantified the digital divide that existed between schools in Metro Manila, Philippines and schools in countries surveyed by the International Association for the Evaluation of Educational Achievement. The researcher determined that unlike students in other countries, students in Metro Manila schools had limited access to computers, software, and the Internet. This implies that Metro Manila students are among the digital poor, with fewer opportunities to access, process, and contribute to digital content. [Copyright &y& Elsevier]

This study proposes an approach in conducting an overall performance evaluation of the integrated flood risk management (IFRM). The proposed approach is a monitoring & evaluation (M&E) framework for IFRM suitable in data-poor areas. The proposed framework has two main tasks: 1) to monitor the measures of the four IFRM strategies (prevention, preparedness, response, and recovery/rehabilitation) by asking experts for qualitative appraisals and 2) to evaluate the monitored measures using fuzzy based multi-criteria evaluation based on priority ranking methodology (FME-PRM). The M&E framework is applied for Metro Manila, Philippines, as a case study, where it enabled the quantification of qualitative data and provided a systematic solution for the weight assignment on the IFRM strategies and measures in Metro Manila. The results successfully show the IFRM performance level at the 13 cities and Metro Manila as a region. The results reveal that Metro Manila is at the "Good" performance level, which indicates that IFRM implementation had already progressed, but the achievements are not yet substantial. [ABSTRACT FROM AUTHOR]

• The new tax schedule of gas slightly reduces emissions but raises the tax revenue. • The new tax schedule of vehicle reduces vehicle fleet but not emissions. • The Euro 6 cars and Euro 4 buses and PUJs significantly improve public health. • The improved accessibility reduces energy demand but not pollutant emissions. • All the low carbon scenarios should be integrated to achieve sustainable mobility. An increase in private vehicle fleet and usage exacerbates the overuse of petroleum products, air quality degradation, and public health risks, among other drawbacks. This study investigated the energy and environmental benefits for private passenger vehicles under various scenarios in Metro Manila, the Philippines. The findings are informative to design policy implications for energy and environmental benefits. The study applied the Gaussian copula-based multinomial logit (MNL)-linear regression to develop the household vehicle ownership and energy consumption model using the disaggregated data of 1,795 households collected in 2017. The simulated vehicle fleet and energy consumption were then adopted to extrapolate energy demand, emissions, and public health risks for a 2010–2050 horizon using the bottom-up approach. Under the baseline scenario, the energy demand and carbon dioxide (CO 2) emissions will reach 5.45 million tonnes of oil equivalent (Mtoe) and 16.93 million tonnes (Mt) in 2050, respectively. The amounts of hydrocarbon (HC), carbon monoxide (CO), sulfur dioxide (SO 2), nitrogen oxides (NO X), particulate matter 10 (PM 10) and particulate matter 2.5 (PM 2.5) emissions, and economic loss of health risks will be 6,214 tonnes (t), 62,136 t, 536 t, 10,550 t, 1,348 t, 996 t, and 237 Million USD, respectively, under the baseline scenario in 2050. Improvement of accessibility significantly reduces energy demand and CO 2 emissions. Introduction of Euro 6 cars and Euro 4 buses and Public Utility Jeepneys noticeably improves public health. The new tax schedules on gas and vehicle maximize the tax revenue. The integration of all the mentioned alternatives can achieve sustainable mobility and urbanization. [ABSTRACT FROM AUTHOR]

Many countries encountered "barriers" or obstacles that hampered the process of adapting to the integrated flood risk management (IFRM) from the traditional hard structural solutions in managing urban flooding. One of the crucial tasks to overcome the barriers is to understand their interrelationships. However, analysis of the interrelationships between the barriers to IFRM adaptation has not been carried out yet. This study attempts to analyze the interrelationships between the barriers to IFRM adaptation using the Interpretive Structural Modeling (ISM) method. The barriers in Metro Manila, a megacity in a developing country, were identified first in this study. Then, the ISM method was slightly modified and applied to analyze the interrelationships of the identified barriers. As a result, we identified 12 barriers which are relatively numerous compared with the developed countries, and so we categorized them into the governance, social, and technological resources aspects. Through the application of the ISM method, the interrelationships of the barriers to IFRM adaptation were systematically analyzed for the first time while also showing their hierarchical diagram. The results of the ISM reveal that barriers in the governance aspect are the most influential in which the lack of a sole organizing body is the most influential barrier. The barriers in the technological resources aspect are the second most influential, while barriers in the social aspect are the least influential and most dependent barriers. The approach presented in this study can be useful for decision makers and practitioners in understanding the interrelationships between the barriers. [ABSTRACT FROM AUTHOR]

Considering the visibility of infrastructural projects as a means of coastal protection against urban sea level change, this paper draws attention to dyking as both a form of 'defense' and as a means of 'dwelling' or living with/from water. By tracing the emergence of a recent donor-funded polder dyke in Metro Manila (Philippines), the paper focuses on the infrastructural politics of coastal protection in a delta megacity, often technocratically framed as a global disaster capital. It illustrates how, as a socio-technological object, a dyke might serve as a distinct mode of governing everyday life along high density urban coastlines. Combining insights from Evolutionary Governance Theory (EGT) and infrastructural anthropology, the paper traces the materialization of the dyke as an evolving 'living' infrastructure, placing it against a broader canvas of urban transformations encompassing contestations around disaster risk reduction, land use, uneven livelihood access, tenurial rights, and neoliberal aesthetics. As a means of transcending the defense/dwelling binary, a typology of four interrelated frames are presented with which to trace localised meanings and practices of dyking as a mode of everyday governance, namely as: a) a line of defence for protective living; b) urban spectacle; c) a buffer zone or marker for land acquisition and; d) a fluid borderland, which at times ruptures the very material fixities and aqua-terrestrial distinctions upon which hard engineering infrastructural solutions are often premised. [ABSTRACT FROM AUTHOR]

Understanding the impact of household characteristics and land use attributes on household vehicle ownership and usage decision is an efficient way of crafting strategic approaches having negative impacts on private vehicle dependency toward a sustainable urban transportation system. This empirical study applied the Gaussian copula-based discrete-continuous choice model to develop an integrated household vehicle ownership and energy consumption model using the unique data sample of 1795 households gathered in 2017 through various areas in Metro Manila, Philippines. The findings necessarily reported that household income is the main factor of household vehicle ownership and energy consumption decision. Households with the presence of older and well-educated household heads are found to be willing to acquire more vehicles. Encouraging urban densification, improvement of road public transport line density, reduction of distance from a residential area to the shortest railway station, and increasing mixture of integral facilities in neighborhoods (i.e., hospitals, markets, schools, and recreation centers) have considerable contributions to build a metropolis with less private vehicle dependency. The developed model was then applied to simulate percentage changes of the vehicle fleet and energy consumption based on various scenarios, and the policy implications based on the empirical findings were also discussed to help policymakers. [ABSTRACT FROM AUTHOR]