National Committee on Marine Sciences (NCMS)
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- A synthesis and review of historical eruptions at Taal Volcano, Southern Luzon, PhilippinesDelos Reyes, Perla J.; Bornas, Ma. Antonia V.; Dominey-Howes, Dale; Pidlaoan, Abigail C.; Magill, Christina R.; Solidum, Renato Jr. U. (Elsevier BV, 2018-02)The Philippines is an area of persistent volcanism, being located in one of the most tectonically active regions in the world. Taal Volcano in Southern Luzon is the second most frequently erupting volcano of the 24 active volcanoes in the Philippines. A comprehensive and critical review of published and unpublished references describing the 33 known historical eruptions of Taal may provide answers to knowledge gaps on past eruptive behavior, processes, and products that could be utilized for hazard and risk assessment of future eruptions. Data on the prehistoric eruptions and evolution of Taal Caldera and subsequent deposits are limited. Only four caldera-forming events were identified based on four mapped ignimbrite deposits. From oldest to youngest, these are the silicic Alitagtag (ALI) and Caloocan (CAL) Pumice Flow deposits, the dacitic Sambong Ignimbrite (SAM), and the basaltic-andesitic Taal Scoria Flow, renamed Scoria Pyroclastic Flow (SFL). Except for SFL with 14C dating yielding 5380 ± 70 to 6830 ± 80 ky, there are no age constraints or estimates of extent for the three older deposits. A comprehensive review of the historical eruptions of Taal Volcano is the central element of this paper and includes all eruptions from AD1572 (the first known historic event) to AD1977. Eruption styles and the interplay between processes and products for each eruption are reinterpreted based on the narrative descriptions from all available accounts. A change of classification of eruption styles and eruptive products is undertaken for some events. At least nine reported eruptions were deemed uncertain including the AD1605-AD1611 event (more likely seismic swarms), the AD1634, AD1635, and AD1645 (may simply be solfataric or hydrothermal activity) events, and the AD1790, AD1825, AD1842, AD1873 and AD1903 events that were listed in recent published and unpublished documents but do not provide any details to describe and confirm the eruptions except for listing a default VEI of 2. Pyroclastic density currents brought devastating impacts to the communities around Taal during the AD1749, AD1754, AD1911 and AD1965 eruptions and remain the biggest threat in the case of renewed volcanic activity. Significant implications for aviation are implied by the narrative of tephra fall dispersal towards Manila, the central gateway of international aviation operation in the Philippines, during the AD1754 eruptions. The dispersal of tephra in the event of an explosive eruption at Taal towards Metro Manila would have catastrophic effects to transport, utilities and business activity, potentially generating enormous economic losses. Hazards from earthquake events associated with future volcanic activity may also have localized impacts. Occurrences of liquefaction phenomena as a consequence of severe ground shaking are interpreted during the AD1749, AD1754, and AD1911 eruptions. More work needs to be done to develop a comprehensive understanding of the hazards and risks associated with an explosive eruption at Taal Volcano, especially related to the older Quaternary caldera-forming eruptions that produced large-volume pyroclastic deposits that are extensively distributed and exposed. We acknowledge that there may be additional prehistoric eruptions where the eruptive products have not been preserved, recognized or reported. Events that cannot be verified or do not have sufficient details to confirm the eruption, have been downgraded to “uncertain”. Eruptions that are confirmed with identified dispersal and emplacement of tephra fall and other eruptive deposits, as interpreted from narrated records, could provide crucial information that may be utilized in hazard assessment.
- Petrology and geochemistry of Camiguin Island, southern Philippines: insights to the source of adakites and other lavas in a complex arc settingCastillo, Paterno R.; Janney, Philip E.; Solidum, Renato Jr. U. (Springer Science and Business Media LLC, 1999-01-21)Camiguin is a small volcanic island located 12 km north of Mindanao Island in southern Philippines. The island consists of four volcanic centers which have erupted basaltic to rhyolitic calcalkaline lavas during the last ∼400 ka. Major element, trace element and Sr, Nd and Pb isotopic data indicate that the volcanic centers have produced a single lava series from a common mantle source. Modeling results indicate that Camiguin lavas were produced by periodic injection of a parental magma into shallow magma chambers allowing assimilation and fractional crystallization (AFC) processes to take place. The chemical and isotopic composition of Camiguin lavas bears strong resemblance to the majority of lavas from the central Mindanao volcanic field confirming that Camiguin is an extension of the tectonically complex Central Mindanao Arc (CMA). The most likely source of Camiguin and most CMA magmas is the mantle wedge metasomatized by fluids dehydrated from a subducted slab. Some Camiguin high-silica lavas are similar to high-silica lavas from Mindanao, which have been identified as “adakites” derived from direct melting of a subducted basaltic crust. More detailed comparison of Camiguin and Mindanao adakites with silicic slab-derived melts and magnesian andesites from the western Aleutians, southernmost Chile and Batan Island in northern Philippines indicates that the Mindanao adakites are not pure slab melts. Rather, the CMA adakites are similar to Camiguin high-silica lavas which are products of an AFC process and have negligible connection to melting of subducted basaltic crust.
- Ocean mapping and other marine activities of the National Mapping and Resource Information Authority (NAMRIA)Carandang, Efren P. (Philippine Council for Aquatic and Marine Research and Development, 2002)This paper describes the various marine activities being undertaken by the National Mapping and Resource Information Authority (NAMRIA) pursuant to its mandate as the central surveying, mapping and resource information agency of the government. NAMRIA gathers marine data through periodic hydrographic and oceanographic surveys and remote sensing techniques, and publishes the results in the form of nautical charts, bathymetric maps and other thematic maps. It also creates marine geographic information systems and databases. As steward of the National Oceanographic Data Center (NODC), the agency participates in international oceanographic data exchange programs, and also serves the marine data and information needs of the local marine science community. NAMRIA's data collection capability got a big boost with the acquisition this year of two multi-disciplinary survey vessels with state-of-the-art systems. With these vessels as platforms, NAMRIA will embark on the comprehensive charting of the Exclusive Economic Zone, and collaborate with the different marine science agencies in the conduct of multi-disciplinary oceanographic cruises.
- Defending Philippine maritime territory and marine resources: Initiatives and problemsCarranza, Ruben R., Jr. (Philippine Council for Aquatic and Marine Research and Development, 2002)The significance of the Philippines' maritime territory and the complexities of its defense are examined. The speaker highlights the integral role of the country's waters in trade, food security, and resource provision. Challenges, including naval limitations and maritime intrusions, are presented, followed by a discussion of defense strategies like selective sea control. The speech concludes with a call for decisive policy actions, diplomatic solutions to territorial conflicts, and improved capabilities to safeguard the nation's maritime interests.
- Moving towards open data, public access, and information sharing to combat marine plastics pollution in the Philippines and the Southeast Asian regionAlindayu, Ricardo C.; Licnachan, Lance Oliver C.; Luzadas, Ramgem L.; Ignacio, Paul Samuel P.; Onda, Deo Florence L. (Elsevier, 2023-09-01)Despite the consistent tagging of countries in Southeast Asia as among the top polluters of plastics in the oceans and the increasing local literature documenting the presence and abundance of plastics in marine environments, there still lacks a comprehensive, open, and accessible repository for marine plastics pollution data in the region. As such, this study presents the development of the PlastiCount Pilipinas portal in line with the call for a common data repository by the Philippines’ National Plan of Action for the Prevention, Reduction, and Management of Marine Litter and the ASEAN Regional Action Plan for Combating Marine Debris in the ASEAN Member States. A total of 14 existing databases were reviewed to identify key features for the online portal implemented to promote ease of access and diversified functionality. For the database, a total of 38 publications, 2 reports, 1 scientific poster, and 3 baselining studies were used to develop the initial ground-truthed baseline for marine plastic pollution, covering 23 provinces and 14 regions across the Philippines. The challenges presented by an observed variation across different methodologies and reporting styles emphasize the critical need to harmonize methods toward generating a more refined national baseline for marine litter. The initial baseline data and other resources such as manuals, information sheets, photographs, news, and publications are uploaded onto a public online portal for viewing and download (https://plasticount.ph/). Data and resource submissions from the public are also accepted and considered for inclusion in the database. The insights gained from developing the online portal and database for the Philippines can be used to inform the development of a regional database for Southeast Asia towards reducing marine litter.
- Creation of an international laboratory network towards global microplastics monitoring harmonisationBakir, Adil; McGoran, Alexandra R.; Silburn, Briony; Russell, Josie; Nel, Holly; Lusher, Amy L.; Amos, Ruth; Shadrack, Ronick S.; Arnold, Shareen J.; Castillo, Cecy; Urbina, Joaquin F.; Barrientos, Eduardo; Sanchez, Henry; Pillay, Keshnee; Human, Lucienne; Swartbooi, Tarryn; Cordova, Muhammad Reza; Sani, Sofia Yuniar; Wijesinghe, T. W. A. Wasantha; Amarathunga, A. A. Deeptha; Gunasekara, Jagath; Somasiri, Sudarshana; mahatantila, Kushani; Liyanage, Sureka; Müller, Moritz; Hee, Yet Yin; Onda, Deo Florence; Jansar, Khairiatul Mardiana; Shiraz, Zana; Amir, Hana; Mayes, Andrew G. (Nature Research, 2024-06-03)Infrastructure is often a limiting factor in microplastics research impacting the production of scientific outputs and monitoring data. International projects are therefore required to promote collaboration and development of national and regional scientific hubs. The Commonwealth Litter Programme and the Ocean Country Partnership Programme were developed to support Global South countries to take actions on plastics entering the oceans. An international laboratory network was developed to provide the infrastructure and in country capacity to conduct the collection and processing of microplastics in environmental samples. The laboratory network was also extended to include a network developed by the University of East Anglia, UK. All the laboratories were provided with similar equipment for the collection, processing and analysis of microplastics in environmental samples. Harmonised protocols and training were also provided in country during laboratory setup to ensure comparability of quality-controlled outputs between laboratories. Such large networks are needed to produce comparable baseline and monitoring assessments.
- Accumulation and exposure classifications of plastics in the different coastal habitats in the western Philippine archipelagoGomez, Norchel Corcia F.; Cragg, Simon M.; Ghiglione, Jean-François; Onda, Deo Florence L. (Elsevier, 2023-11)Studies consistently ranked the Philippines as one of the top contributors of plastic wastes leaking into the ocean. However, most of these were based on probabilities and estimates due to lack of comprehensive ground-truth data, resulting also in the limited understanding of the contributing factors and drivers of local pollution. This makes it challenging to develop science-driven and locally-contextualized policies and interventions to mitigate the problem. Here, 56 sites from different coastal habitats in the western Philippine archipelago were surveyed for macroplastics standing stock, representing geographic regions with varying demography and economic activities. Clustering of sites revealed three potential influencing factors to plastic accumulation: population density, wind and oceanic transport, and habitat type. Notably, the amount and types of dominant plastics per geographic region varied significantly. Single-use plastics (food packaging and sachets) were the most abundant in sites adjacent to densely populated and highly urbanized areas (Manila Bay and eastern Palawan), while fishing-related materials dominated in less populated and fishing-dominated communities (western Palawan and Bolinao), suggesting the local industries significantly contributing to the mismanaged plastics in the surveyed sites. Meanwhile, isolated areas such as islands were characterized by the abundance of buoyant materials (drinking bottles and hygiene product containers), emphasizing the role of oceanic transport and strong connectivity in the oceans. Exposure assessment also identified single-use and fishing-related plastics to be of “high exposure (Type 4)” due to their high abundance and high occurrence. These increase their chances of encountering and interacting with organisms and habitats, thus, resulting into more potential harm. This study is the first comprehensive work done in western Philippines, and results will help contextualize local pollution, facilitating more effective management and policymaking.