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NH-T1007 Impacts of Climate Modes on Temperature Extremes Over Bangladesh Using Statistical Methods

Mr Md Wahiduzzaman %#+ Nanjing University of Information Science and Technology, China
Prof Jing-Jia Luo Nanjing University of Information Science & Technology, China

Bangladesh is sensitive to weather and climate extremes, which have a serious impact on agriculture, ecosystem, and livelihood. However, there is no systematic investigation to explore the effect of climate modes on temperature extremes over Bangladesh. A total of 11 temperature extreme indices based on the daily maximum and minimum temperature data for 38 years (1980—2017) have been calculated. Cross-wavelet transforms and Pearson correlation coefficient have been used to identify the relationship between temperature extremes and three climate modes-EL Nino Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and North Atlantic Oscillation (NAO). Detrended fluctuation analysis (DFA) method was applied to predict the long-term relationship among temperature indices. Results showed that warm (cold) temperature extreme indices increased (decreased) significantly. There was a significant upward trend in the diurnal temperature range (DTR) and tropical nights (TR) except for growing season length (GLS). ENSO and IOD had a strong negative (positive) impact on cold (warm) temperature indices, whereas NAO had a strong negative influence on variability temperature indices in Bangladesh. Temperature extreme had a long-term relationship based on DFA (a>0.5), implying that the temperature extremes will remain their present trend line in the future period. The Poisson regression model showed that the highest probability (65%) of having a 2-4 warm spell duration indicator (WSDI) (days/decade) is consistent with the observation, which is shown in the cross-wavelet transform and spatial analysis.

NH-T1009 Sdg Target Interactions: the Philippine Analysis of Indivisible and Cancelling Targets

Dr Vena Pearl Bongolan %#+ University of the Philippines Diliman, Philippines
Mr Arian Allenson Valdez Department of Computer Science, UP Diliman, Philippines
Prof Roselle Leah Rivera College of Social Work and Community Development, UP Diliman, Philippines

The United Nations developed the 17 Sustainable Development Goals (SDGs), with 169 targets, to serve as a plan for solving the world’s problems and achieving a more sustainable future. This is modeled as a graph with the targets as nodes, and with the interaction between targets as the edges of the graph. An exhaustive binary comparison is done to analyze the intra- and inter-goal target interactions, entailing over 14000 comparisons. The task is to assign a ‘color’ to an edge:  positive (indivisible), zero (consistent) or negative (cancelling). This is done via a panel of experts who will evaluate the target interactions, through a web application that was developed for coloring the edges. This is an on-going study, and so far, of the 1256 edges colored, only 36 are cancelling (negative), or 2.86%; more than 97% are positive interactions. So far, the “most negative” interactions involve: “Climate Change”; “Life Below Water”; “Peace, Justice and Strong Institutions”;  and “Decent Work and Economic Growth”.  Most useful for planning might be the “longest path of positive targets” feature, which searches, via a directed acrylic graph and a topological sort, for a path with only positive or neutral edges, avoiding targets which have red edges emanating from them, i.e., a path of targets that have no conflicts with other targets. Currently, this path has more than 130 nodes. This study can help researchers analyze which targets enable or constrain each other, what mitigation can be done to avoid conflicts,  and can be configured for sub-national or regional study. 

NH-T1008 Frequent Natural Disasters In The Himalayan Region: Impact Of Climate Change

Dr Feng JING % Institute of Earthquake Forecasting, China Earthquake Administration, China
Mr Ramesh Singh #+ Chapman University , United States

The nature and dynamics of the Himalaya varies from west to east, and the region is source of dense network of rivers, drained through the Indo-Gangetic plains. The towering Himalayan region protects trans-boundary long range pollutants from the Arabia peninsula and outflow of pollutants from the densely populated Indo-Gangetic Plains. These pollutants blanket the snow and glacier covers and show dynamic nature over the years that enhance melting of the snow glaciers. Over the years, the pollutants have played an important role in impacting the lower and higher Himalaya from west to east that have change the optical and microwave response of satellites showing characteristics of surface and snow/glaciers. Such dynamic nature of the Himalaya shows a strong coupling between land use/land cover, snow/glacier covers, long term change in meteorological and atmospheric parameters.  The impacts are seen from west to east along the Himalaya that led to the changes in the mass balance, water load, atmospheric parameters and interaction between snow/glacier and atmosphere, that triggers natural hazards such as landslides, rockslides, forest fires, snow avalanches and impact the stability of slopes. A detailed discussion using multi satellite and ground data will be discussed in the observed recent natural hazards in the Himalayan region.    

NH-T1001 A Tale of Two Rapidly-intensifying Super Typhoons: Hagibis (2019) and Haiyan (2013)

Prof I-I Lin %#+ National Taiwan University, Taiwan

Devastating Japan in October 2019, Supertyphoon (STY) Hagibis was an important typhoon in the history of the Pacific. A striking feature of Hagibis was its explosive RI (rapid intensification). In 24 h, Hagibis intensified by 100 kt, making it one of the fastest-intensifying typhoons ever observed. After RI, Hagibis’s intensification stalled. Using the current typhoon intensity record holder, i.e., STY Haiyan (2013), as a benchmark, this work explores the intensity evolution differences of these 2 high-impact STYs.We found that the extremely high pre-storm sea surface temperature reaching 30.5∘C, deep/warm pre-storm ocean heat content reaching 160 kJ cm-2, fast forward storm motion of ~8 m s-1, small during-storm ocean cooling effect of ~ 0.5∘C, significant thunderstorm activity at its center, and rapid eyewall contraction were all important contributors to Hagibis’s impressive intensification. There was 36% more air-sea flux for Hagibis’s RI than for Haiyan’s. After its spectacular RI, Hagibis’s intensification stopped, despite favorable environments. Haiyan, by contrast, continued to intensify, reaching its record-breaking intensity of 170 kt. A key finding here is the multiple pathways that storm size affected the intensity evolution for both typhoons. After RI, Hagibis experienced a major size expansion, becoming the largest typhoon on record in the Pacific. This size enlargement, combined with a reduction in storm translational speed, induced stronger ocean cooling that reduced ocean flux and hindered intensification. The large storm size also contributed to slower eyewall replacement cycles (ERCs), which prolonged the negative impact of the ERC on intensification. Reference: Lin, I-I*, Robert F. Rogers*, Hsiao-Ching Huang, Yi-Chun Liao, Derrick Herndon, Jin-Yi Yu, Ya-Ting Chang, Jun A. Zhang, Christina M. Patricola, Iam-Fei Pun, Chun-Chi Lien, A Tale of Two Rapidly-Intensifying Supertyphoons: Hagibis (2019) and Haiyan (2013), Bulletin of the American Meteorological Society, doi: 10.1175/BAMS-D-20-0223.1, Apr. 2021.

NH-T1003 Disparity of Beach Recovery in Natural and Manmade Urban Coasts : a Case Study of Hong Kong Under 2018 Super Typhoon Mangkhut

Dr Hon Chim Chiu %#+ Hong Kong Baptist University Department of Geography, Hong Kong SAR
Ms Kwan Wai Sherla Lee Hong Kong Baptist University, Hong Kong SAR

While Hong Kong does not qualify as a megacity under some definitions (eg., UN-HABITAT), its natural coastal landform afforded a variety of landscapes and cityscapes within the metropolitan area. Here, we showed that there are significant disparities in exposure and vulnerabilities to natural hazards for these different landforms, as illustrated in the attack of "Super Typhoon" Mangkhut in September 2018. Out of the three sites under investigation, Ma On Shan jetty inside the engineered Tolo Channel suffered erosion but natural recovery processes were observed to have replenished most of the loss in one season. Such resilience and self-recovering abilities in a human modified coastal landscape could serve as a potential model for future developments. Another site, the artificial beach “Golden Beach” near Tuen Mun New Town, received artificial sand replenishment at a near decadal frequency since the 1970s. No natural replenishment of sand was observed, the Government agencies had then decided to recharge the foreshore with backshore deposits, which was observed to have accumulated during the typhoon season, partly due to land development at the backshore. Such policy of utility focused beach nourishment could face challenges in future higher sea level scenarioes. As the equilibrium height of each component of the beach system rise, beach deposits could potentially encroaching building and transport structures. Tai Long Wan (Big Wave Bay), a natural embayment in southern Hong Kong Island, was the third system under study. As one of the more popular bathing beaches in Hong Kong, the construction of sea wall, artificially vegetating the backshore dune, as well as village development impacted the natural recovery of the beach, evidenced in the inability of the dune to recover from Mangkhut. This become one clear evidence that village housing and infrastructure facing additional risks in a warming climate and a higher sea level.

NH-T1004 Decoding the Role of Climate Change in the Hydro-climatic Disasters of South Peninsular India

Ms Micky Mathew %#+ National Centre for Earth Science Studies, India
Mr Sreelash Krishnan Kutty National Centre for Earth Science Studies, India
Ms Merin Mariam Mathew National Centre for Earth Science Studies, India
Dr D. Padmalal ESSO-National Centre for Earth Science Studies (NCESS), Ministry of Earth Sciences, Government of India, Post Box No 7250, Akkulam, Thiruvananthapuram -695011, Kerala, India, India

Climate change synergistically with urbanization, impacts the hydro-climatology of South Peninsular India (SPI). The recurrence of extreme rainfall with higher return period is currently leading to increased frequency of floods in low resilience regions like SPI. IPCC-AR6 reported the increasing frequencies of extreme rainfall-induced hydroclimatic disasters in South Asia. Most of the flood events occurring in SPI are due to extreme rainfall events. Hydroclimatic disasters due to anchored bias affect water security and the overall economy.  Detailed analysis of the historical rainfall record can provide significant inputs on the changing patterns of regional rainfall which in turn can aid in mitigating hydroclimatic hazards. Therefore, a long-term expanding sliding window trend analysis was conducted on the two climatologically contrasting regions of SPI. The study revealed the reduction in peakedness of rainfall during July month and distribution of this reduced rainfall being continued to other months of the year in both the regions. An accelerated change in rainfall pattern after 2000 was observed in the Eastern part of SPI (Semiarid region), while the Western counterpart (Humid region) shows a deceleration in annual rainfall. An increase in hydro-climatic hazards (floods and landslides) in SPI, induced by extreme precipitation during low expectancy months in the past decade is a byproduct of this shift in the regional rainfall pattern. The 2018 and 2019 Kerala flood, and 2015 Chennai flood are the major flood events with devastating losses that SPI witnessed during the past decade. A flood inundation library for a selected river basin was created using a physical-based watershed modeling approach for different scenarios of rainfall events. The flood inundation library is aimed at providing a near real-time map of the potential zone of flood inundation along with an uncertainty level and thereby aiding the decision-makers for evacuation and mitigation plans.

NH-T1005 Detection and Attribution of the Spatio-temporal Trend of Climatic Disaster Impacts and Vulnerability in Nepal

Mr Dipesh Chapagain %#+ Center for Development Research (ZEF), University of Bonn, Germany
Dr Luna Bharati Center for Development Research (ZEF), University of Bonn, Germany
Prof Christian Borgemeister Center for Development Research (ZEF), University of Bonn, Germany

The impacts of climatic disasters have been rising globally. Several studies argue that this upward trend is due to rapid growth in the population and wealth exposed to disasters. Others argue that rising extreme weather events due to anthropogenic climate change are responsible for the increase. Hence, the causes of the increase in disaster impacts remain elusive. Disaster impacts are higher in low-income countries, but existing studies are mostly from developed countries or at the cross-country level. Here we assess the spatiotemporal trends of climatic disaster impacts and vulnerability and their attribution to climatic and socioeconomic factors at the subnational scale in a low-income country, using Nepal as a case study. Loss of life is the most extreme consequence of disasters. Therefore, we employed human mortality as a measure of disaster impacts, and mortality normalized by exposed population as a measure of human vulnerability. We found that climatic disaster frequency and mortality increased in Nepal from 1991 to 2020. However, vulnerability decreased, most likely due to economic growth and progress in disaster risk reduction and climate change adaptation. Disaster mortality is positively correlated with disaster frequency and negatively correlated with per capita income but is not correlated with exposed population. Hence, population growth may not have caused the rise in disaster mortality in Nepal. The strong rise in disaster incidence, potentially due to climate change, has overcome the effect of decreasing vulnerability and caused the rise in disaster mortality.

NH-T1006 Assessment of the Vulnerability of Fixed Assets to Permafrost Hazards Until 2050: the Case of the Russian Arctic

Dr Svetlana Badina %#+ Lomonosov Moscow State University, Faculty of Geography, Russian Federation

According to modern scientific forecasts, global climate change will lead to permafrost degradation in a significant part of the Russian Arctic by the second half of the 21st century. Permafrost thaw will cause massive deformation and destruction of fixed assets. The purpose of this research is to estimate the value of buildings and structures located in the Russian Arctic permafrost zone, an important baseline for further direct damage prediction. Currently, there is no reliable and comprehensive information about the value of buildings and structures in the risk area. Making such an estimate would require not only determining the current value of existing buildings and structures, but also forecasting what will happen between now and the second half of the 21st century. Author uses an original self-developed method to assess the value of buildings and structures in different Russian Arctic municipalities that takes into account the value of housing stock, existing and future buildings and structures by economic sector. According to our calculations, the total value of buildings and structures in the Russian Arctic permafrost zone will be about US$133.5 billion by the second half of the 21st century. Mapping these results onto forecasts of geocryological transformations, the value of buildings and structures in the areas of maximum predicted permafrost thaw will be about US$94.5 billion. Thus, we can conclude that the areas of maximum rapid permafrost degradation typically intersect with those areas where the highest total value of buildings are located. As such, the natural risk level in the most developed parts of the Russian Arctic is likely to increase in the medium and long term. These territories must elaborate and implement relevant measures to help society and the economy adapt to changes in permafrost. Acknowledgements:this work was supported by the Russian Science Foundation (project No21-77-00047).

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NH-T3005 Comprehensive Comparison of Flexible, Silt and Rigid Barriers in Mitigating Multiphase Debris Flows: Insights from Large-scale Simulations

Dr Yong KONG %+ The University of Hong Kong, Hong Kong SAR
Dr Mingfu Guan # The University of Hong Kong, Hong Kong SAR
Dr XIngyue Li Swiss Federal Institute of Technology, Switzerland

The steep hilly terrain, intense rainstorms, and dense population render Hong Kong highly vulnerable to debris flow hazards, which can be reduced by placing flexible, silt and rigid barriers in the runout zones. However, quantitative comparisons between different barriers in intercepting debris flows are lacking, due to the difficulties associated with the analysis of multi-body and multi-phase interactions among the barrier, the solid and the fluid in debris flows. Here, we perform the coupled computational fluid dynamics and discrete element method (CFD-DEM) simulations to probe the intricate three-way interactions. Specifically, a debris flow is simulated as a mixture of discrete gap-graded particles and a continuous viscous slurry. A flexible barrier consisting of interlocking ring elements, brakes, and cables is modeled. The numerical results have reasonably captured both field and experimental observations on key flow-structure interactions. We quantitatively compare the results of 24 large-scale simulations of debris flows with pre-impact Froude numbers ranging from 0.9 to 7.5 in terms of the Spatio-temporal impact load distributions, impact durations, overspreading flow dynamics as well as the impact mechanism transitions with different barriers. This allows to clarify the inter-twined relationships among the flow dynamics, barrier types, and impact loads for the first time. After the transition of impact mechanisms from pile-up to runup, flexible barriers can significantly reduce impact loads and overspreading flow dynamics by the extension of impact duration, the passing through of materials, and barrier deformations, as compared to silt and rigid barriers. Therefore, the flexible barrier can be more effective and pragmatic in arresting debris flows with faster flow dynamics. This study helps reveal the fundamental distinctions of flexible, silt and rigid debris-resisting barriers, which may provide a useful reference for their practical engineering analysis. (The study was supported by RGC/HK #27202419 and NSFC #51909227.)

NH-T3007 Application of Refraction Microtremor for Site Characterization and Liquefaction Potential Assessment in Metro Manila, Philippines

Mr Oliver Paul Halasan %#+ Philippine Institute of Volcanology and Seismology, Philippines
Mr Arturo Daag Philippine Institute of Volcanology and Seismology, Philippines

The densely populated region of Metro Manila in the Philippines is exposed to a variety of seismic hazards. This region is traversed by the active, strike-slip Valley Fault System, which has the potential to generate a Mw 7.2 earthquake with ground shaking up to Intensity VII. The western sector of this area is particularly susceptible to liquefaction, due to its proximity to the Manila Bay and the underlying coastal and fluvio-deltaic Quaternary Alluvium deposits. In the country, geotechnical investigations and liquefaction potential assessment are commonly done using Standard Penetration Test (SPT) drillings. This approach may be more precise; however, it is also more costly and can only produce a single, one-dimensional profile data. This calls for the use of alternative techniques for shallow subsurface characterization such as through geophysics, as it can be faster, more economical, and can establish lateral continuity between borehole profiles.To enhance the geotechnical description of twenty-five sites situated in the liquefiable zone in Metro Manila, shear wave velocity (Vs) profiles were obtained from refraction microtremor surveys (ReMi), to augment previously conducted SPT soil investigations. Overall results show that liquefaction potential assessment using ReMi and SPT are generally comparable. Moreover, statistical analysis between uncorrected SPT-N values and Vs using ReMi shows promising correlation coefficients. New empirical formulae suggested in this study to relate the two parameters are also compared to other published empirical relationships. This study demonstrates the benefit of incorporating shear-wave velocity estimates from ReMi into the geotechnical investigations to further develop more meaningful ground models and enhance liquefaction risk mitigation.

NH-T3008 Soil Investigation And Liquefaction Potential Evaluation Of Selected Schools In Metro Manila, Philippines Using Screw Driving Sounding (SDS) Test

Ms Katelyn Sochayseng %#+ Philippine Institute of Volcanology and Seismology, Philippines
Mr Arturo Daag Philippine Institute of Volcanology and Seismology, Philippines

In the Philippines, conventional methods like Standard Penetration Test (SPT) and Cone Penetration Test (CPT) are the most common tools in determining a site's soil properties and liquefaction potential. However, both have certain specifications and drawbacks that lead to high costs, more labor force, and low data accuracy due to human error. Thus, the Screw Driving Sounding (SDS) test was developed to solve the disadvantages mentioned above. The SDS test is a relatively new limited probe hole drilling tool used to investigate the soil classification and estimate equivalent SPT parameters such as N-value and Fines Content. Its advantages include a portable machine-driven design, a more straightforward test system, and better penetration cost efficiency.

This paper presents the correlation analysis of geotechnical parameters between the available SPT and the surveyed SDS data in selected schools of the Metro Manila Area, Philippines. Furthermore, estimated parameters from the SDS test are also used for the site-specific liquefaction assessment of thirty-three (33) schools which are calculated from various liquefaction potential indices. As a result, it shows that the SDS test can be an effective alternative method in soil investigation and quantification of the liquefaction potential of a site.

NH-T3006 Spatial Aspects of Urban Population Vulnerability to Natural and Man-made Hazards: Specifics of Russian Cities

Mr Alexander Mikhaylov %#+ Plekhanov Russian University of Economics, Russian Federation
Dr Svetlana Badina Plekhanov Russian University of Economics, Russian Federation
Mr Roman Babkin Plekhanov Russian University of Economics, Russian Federation, Russian Federation
Mr Roman Bobrovsky Plekhanov Russian University of Economics, Russian Federation, Russian Federation, Russian Federation

The report focuses on an assessment of spatial differences of vulnerability levels for the population of city to possible natural and man-made hazards. Particular attention is paid to estimation of the actual population size and aspects of its intraday spatial movement. In addition to official statistical sources, we used data of mobile operators, which made it possible to characterize the localization of subscribers at a certain point in time with the maximal degree of reliability. We used the case of the city of Moscow in order to verify our concepts and subsequently use them on other cases of Russian cities.Particular attention was paid to the effect of increasing the likelihood of man-made emergencies as a result of natural disasters. In this case vulnerability levels mostly rise in the areas of sanitary protection zones of industrial enterprises The minimal population number concentrated there (at night) in Moscow is 1590 thousand people, which is about 14.5% of the population of Moscow at this time, and the maximum (in the daytime) is 2940 thousand people (24%). Therefore the vulnerability of the population of Moscow in the daytime increases almost twofold. According to the official documents the numbers are incomparably less than the values which we have obtained (only 93.2 thousand people). The results show the inconsistency of existing approaches to vulnerability assessment for these territories based on official social statistics. With the obtained results we have created the typology of urban areas according to the specifics of their vulnerability. Moreover, we paid particular attention to its future adaptation to other Russian cities, especially remote large cities in the regions of the Far East.
The research was funded by the Russian Foundation for Basic Research and Moscow City Government according to the project 21-35-70004.

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NH-T4002 Development on X-band Weather Radar Implementing Frequency Modulated Continuous Wave (fmcw) Technology

Mr Daniel Hutapea %#+ Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Dr Erwin Makmur Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Achmad Sasmito Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Mohamad Husein Nurrahmat Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Welly Fitria BMKG, Indonesia
Mr Alfan Praja Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Sri Puji Rahayu Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Hastuadi Harsa BMKG, Indonesia
Mr Roni Kurniawan Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Muhammad Najib Habibie BMKG, Indonesia
Mr Yunus Swarinoto Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Nelly Florida Riama Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Rahayu Sapta Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Oktanto Winarko Labs 247, Indonesia
Dr Asif Awaludin National Institute of Aeronautics and Space, Indonesia
Mr Fatkhuroyan Fatkhuroyan BMKG (Agency for meteorology climatology and geophysics), Indonesia
Mr Angga Prayogo Indonesian Agency for Meteorology, Climatology, and Geophysics , Indonesia

Indonesia is a country prone to hydro-meteorological disasters. This condition needs special attention to make policy and action on mitigation. The Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG) provides meteorology information to support disaster mitigation. BMKG has installed 41 weather radars to cover the Indonesia region. Nevertheless, the radar amount that BMKG has still cannot cover the Indonesia region because of its unique and complex topography. Nowadays, the need for weather radar in Indonesia is mainly met by imports from other countries. Therefore, the noteworthiness of independence in developing and producing domestic radar becomes one crucial step to be done. To fulfill the radar needs, BMKG, in cooperation with a private partner developing weather radar.The weather radar developed is a non-polarimetric radar using Frequency Modulated Continuous Wave (FMCW) technology. The FMCW modulation technique on the radar is mainly limited to radar safety (surveillance) and maritime security (coastal). This weather radar was developed using the same method as the maritime security and surveillance added with several types of hardware-specific to weather radars. The development of this weather radar proceeds along several stages such as; 1. Generating X-Band weather radar basic design; 2. Implementation of FMCW’s work principle on radar system; 3. Hardware and signal processing module development; 4. Software development; and 5. Weather radar operational test. This research activity has produced a prototype of an X-band weather radar. The radar has a high scanning rate and is capable of high-density observations in elevation. The FMCW technology takes only 3 seconds to perform a full-scanning azimuth field with a maximum range of 60 km. An operational test that has been completed by comparing the developed radar with existing radar obtained that the radar can capture objects the same as the existing radar. However, this radar requires development to achieve better results.

NH-T4003 Multi-frequency Ground Penetrating Radar and Single Station 3-component Microtremor for Groundwater and Shallow Shear Wave Velocity Mapping: Implications to Local Site Vulnerability

Mr Leandro Ernesto Aque %#+ DOST-PHIVOLCS, Philippines
Mr Mij Dela Cruz DOST-PHIVOLCS, Philippines
Mr Arturo Daag DOST-PHIVOLCS, Philippines

Geophysical instruments are well-known for characterization with varying degrees of potential for detailed imaging of the subsurface. In this study, the application of two well-established surface-based geophysical techniques, namely Ground Penetrating Radar (GPR) and 3-Component Microtremor (3-CMT), were used to investigate site-specific vulnerability to earthquake hazard such as liquefaction. We focused on quantifying variations in depths to groundwater and bedrock as well as shear stiffness of near surface layers in selected experimental school sites in the megacity of Manila, Philippines. Survey transects were distributed to cover the entire school for a detailed analysis. For the microtremor survey, we used Rayleigh wave ellipticity curves for constrained inversion to construct Vs profiles reaching down to bedrock. Moreover, the GPR software RadExplorer was used to process and interpret the radargrams to delineate groundwater table depth. 
Our integrated results show low shear wave velocities and deep depths-to-bedrock with shallow groundwater table contributing to the liquefaction susceptibility established by PHIVOLCS. Augmenting this is the proximity of earthquake generators capable of producing destructive earthquakes (PHIVOLCS Earthquake Intensity Scale VII), such as the West Valley Fault (WVF). This is important because public schools are used as critical and evacuation facilities in times of natural calamities. This study shows that the methodology can be used as a rapid and economical alternative to conventional drilling techniques for site vulnerability estimation. Furthermore, it aims to make the schools more resilient to the hazards imposed by these events.

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NH-T5001 Discrete-continuous Model for Submarine Mass Failure-induced Tsunamigenesis

Mr Jose Marie Antonio Miñoza %#+ University of the Philippines Diliman, Philippines
Dr Vena Pearl Bongolan University of the Philippines Diliman, Philippines

Recent studies on submarine landslides, also known as submarine mass failures (SMF), show that they can be sources of hazardous tsunamis. Discrete elements of submarine mass failures such as rockfalls are believed to be captured using a cellular automata model, while tsunami waves are often best described using Navier-Stokes equations. Thus, this study proposes a discrete-continuous coupling model. The cellular automata model is derived for submarine mass failure through an ultradiscretization of the simple diffusion equation. This will show the change in height of the cell and will be used as a displacement vector in solving depth-averaged Navier-Stokes Equations for generating tsunami waves.
       
Simulation results on the Anak Krakatau Flank Collapse show that the model has been able to achieve 78.65% accuracy, and 88.95% accuracy when disregarding complex terrains of the domain area. While the tsunami simulation on the NorthwestBorneo Trough produced a wave height of 8.76 meters with 23.99 m/s propagating near shorelines of Balabac Island, Palawan. On the other hand, tsunami wave run-up on Brunei is 1.14 meters and on Sabah is 2.18 meters. Additionally, the model experiments suggest that the coupled model communicates well and is able to provide high percentages of total released energy transferred, 90.56% on Anak Krakatau Flank Collapse simulation and 92.91% on Northwest Borneo Trough simulation.

NH-T5002 Development of Rainfall Estimation and Nowcasting Model Using Himawari-8 (resmma-8)

Dr Erwin Makmur %#+ Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Achmad Sasmito Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Andersen Panjaitan Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Mohamad Husein Nurrahmat Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Welly Fitria BMKG, Indonesia
Mr Alfan Praja Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Sri Puji Rahayu Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Hastuadi Harsa BMKG, Indonesia
Mr Roni Kurniawan Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Daniel Hutapea Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Muhammad Najib Habibie BMKG, Indonesia
Mr Jaka Paski Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Yunus Swarinoto Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Nelly Florida Riama Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Rahayu Sapta Agency for Meteorology, Climatology and Geophysics, Indonesia

Estimates of rainfall using satellite data have lower accuracy than radar or rain gauge data. However, with a regular number of observation points and wide coverage, it can estimate rainfall in areas that are impossible or difficult to observed with radar, such as mountains or oceans area. The territory of Indonesia which has an area of ​​2/3 of the ocean and many mountains is a suitable area for the application of rainfall estimation using satellites. By modifying the empirical equation obtained by Vicente et.al, it is possible to calculate the estimated rainfall using Himawari-8 satellite data. Observations were made every 10 minutes with a spatial resolution of 2 km. The modifications made are parallax correction, surface elevation correction, and cirrus filtering. The results of this modification provide a better accuracy correction. Now, cloud monitoring and nowcasting can be accessed in real-time using the telegram application on mobile phones.

NH-T5003 Development InaNWP to Improve Weather Forecasts Accuracy in Indonesia

Mr Fatkhuroyan Fatkhuroyan %#+ BMKG (Agency for meteorology climatology and geophysics), Indonesia
Mr Wido Hanggoro BMKG (Agency for meteorology climatology and geophysics), Indonesia
Dr Urip Haryoko Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Donaldi Permana Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Dr Erwin Makmur Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Nelly Florida Riama Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Yunus Swarinoto Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Sri Puji Rahayu Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Mohamad Husein Nurrahmat Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Achmad Sasmito Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Rahayu Sapta Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Jaka Paski Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Welly Fitria BMKG, Indonesia
Mr Alfan Praja Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Hastuadi Harsa BMKG, Indonesia
Mr Roni Kurniawan Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Muhammad Najib Habibie BMKG, Indonesia
Mr Daniel Hutapea Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Danang Eko Nuryanto BMKG (Agency for meteorology climatology and geophysics), Indonesia
Mr Rofif Zainul Muttaqin BMKG (Agency for meteorology climatology and geophysics), Indonesia
Mr Priyatna Kusumah BMKG (Agency for meteorology climatology and geophysics), Indonesia
Mr Utoyo Ajie Linarka BMKG (Agency for meteorology climatology and geophysics), Indonesia

Indonesian agency for meteorology climatology and geophysics (BMKG) has task to serve and give information about weather forecast to Indonesian citizen. Today, BMKG use numerical weather model which only use global forecast model as input to their regional weather model. At this study, the InaNWP (Indonesian Numerical Weather Prediction) is built to improve the accuracy of the forecast by assimilating around 350 surface observation data and 27 weather radars around Indonesia from BMKG stations into the weather model. The domains of the model are Indonesia with 9 km resolution and Java with 3 km resolution. The forecast range is 3 days ahead with every 3-hour timestep. the result shows good improvement when use assimilation. The accuracy  score is 0.6 when compare to surface observation and about 0.7 when compare to gsmap satellite rainfall observation.

NH-T5004 The Effect of Enso on Rainfall Prediction Performance Using Seasonal Arima in Indonesia

Mr Alfan Praja %#+ Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Hastuadi Harsa BMKG, Indonesia
Dr Erwin Makmur Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Donaldi Permana Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Rahayu Sapta Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Roni Kurniawan Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Muhammad Najib Habibie BMKG, Indonesia
Ms Sri Puji Rahayu Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Jaka Paski Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Daniel Hutapea Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Fatkhuroyan Fatkhuroyan BMKG (Agency for meteorology climatology and geophysics), Indonesia
Ms Welly Fitria BMKG, Indonesia
Mr Mohamad Husein Nurrahmat Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Yunus Swarinoto Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Mr Achmad Sasmito Indonesian Agency for Meteorology, Climatology and Geophysics, Indonesia
Ms Nelly Florida Riama Agency for Meteorology, Climatology and Geophysics, Indonesia

The climate of the Indonesian region is strongly influenced by global phenomena such as ENSO (El Nino Southern Oscillation). ENSO has a hot period called El Nino and a cold period called La Nina. Various studies were conducted to obtain the best prediction results to reveal this phenomenon. One of the prediction methods that can be used is to use Seasonal ARIMA (Autoregressive integrated Moving Average). This study aims to see the performance of the Seasonal ARIMA model in predicting monthly rainfall in El Nino and La Nina years. The data used as model input is daily average data from January 1971 to December 2018. The data sample locations are Indonesian waters and land areas. The identification of the Seasonal ARIMA model is carried out in the year that represents the El Nino and La Nina. The performance of the Seasonal ARIMA model is measured by comparing the values ​​of the correlation coefficient, RMSE and MAE. The results show that the performance of monthly rainfall predictions in El Nino years is better than the predictions of monthly rainfall in La Nina years.

NH-T5005 School Opening Simulation Using a Covid-19 Agent-based Model with Contact Probabilities for Pasig and Quezon City, Philippines

Mr Jimuel Jr Celeste %#+ University of the Philippines Diliman, Philippines
Ms Jerica Reyes Global Shapers Manila, Philippines, Philippines
Mr Johnathan Watkins PILAR Research Network, London, United Kingdom
Dr Vena Pearl Bongolan University of the Philippines Diliman, Philippines

The COVID-19 pandemic prompted schools to close in 2020, and with its negative impact on the quality of learning, the conversation shifts to the opening scenarios. In this study, we simulated school opening scenarios in Pasig and Quezon City, Philippines using an age-stratified, quarantine-modified SEIR COVID-19 agent-based model with contact probabilities taken from pre-pandemic estimates. The model projected that with an abrupt 100% school opening, without the proper observation of non-pharmacological interventions (NPIs), i.e., mask-wearing and physical distance, infections may increase up to 59.90% for Pasig City and 64.38% for Quezon City with respect to the no opening scenario. Meanwhile, in an ideal scenario where everyone properly observes NPIs during an abrupt opening, the model projects that infections may dip by 11.2% lower than the no opening scenario—a demonstration of the importance of NPIs in stopping the transmission of the disease inside and outside of schools. In addition, the model projected that in a modest 25% opening in Quezon City, infections will increase only by 10.63% and deaths by 1.11%, given that everyone wears a mask and at least 70% observe physical distance. The results of our study suggests that an abrupt 100% school opening is not recommended for Pasig or Quezon City without the stringent observation of NPIs, i.e., 100% mask-wearing and physical distance. Without the proper observation of these NPIs, infections may overwhelm the already busy healthcare system. Alternatively, policy-makers may opt to open schools at a moderate 25% capacity, a seemingly manageable case when combined with the stringent observation of NPIs. These results may guide the policy-makers in Pasig and Quezon City, Philippines.

NH-T5006 Tsunami Early Warning Algorithm Based on Ocean Bottom Sensor S-net System in Tohoku, Japan

Mr Yao Li %#+ Western University, Canada

A tsunami is one of the most serious natural disasters, posing a great threat to the safety of people’s lives and properties in coastal communities. The purpose of this study is to develop an effective and robust algorithm for tsunami early warning using tsunami wave data from ocean bottom sensor (OBS) arrays. This study focuses on the Tohoku region of Japan, where a new OBS S-net system, consisting of 150 sensors, has been deployed. To calibrate the tsunami early warning system using realistic tsunami wave profiles at the S-net stations, 4000 stochastic source models have been generated. In this study, multiple linear regression analysis is first used to build models, and then AIC forward selection and Knee point are applied to select sensors with the most significant effect. The model performances are compared against the base model, which only uses the earthquake’s magnitude and location. The result indicates that estimating tsunami height via S-net improves accuracy. Adding additional sensors helps the models estimate the height more accurately when the same earthquake is triggered. An optimal waiting time is identified to be five minutes, which contains enough information to estimate the tsunami wave height and leaves relatively plenty of time for people evacuating from the coast. Besides, adding five stations from the S-net improves the accuracy of the estimation most significantly. Using five stations is an efficient way to improve tsunami forecasting, and this number of stations can be more easily deployed globally from an economical perspective. This study definitively shows that the S-net sensors and stochastic tsunami wave data have a significant effect on developing a robust tsunami warning algorithm.

NH-T5007 Implementation of First Earthquake Early Warning System for Northern India

Mr Govind Rathore %#+ Indian Institute of Technology Roorkee, India
Dr Pankaj Kumar Indian Institute of Technology Roorkee, India
Dr Kamal Kamal Indian Institute of Technology Roorkee, India
Dr Mukat Sharma Indian Institute of Technology Roorkee, India
Dr Ravi S. Jakka Indian Institute of Technology Roorkee, India
Dr Ashok Kumar Indian Institute of Technology Roorkee, India
Dr Bhanu Chamoli Indian Institute of Technology Roorkee, India

Himalaya is well known for its active seismicity and it has potential to generate a great earthquake therefore the Uttarakhand Government and IIT Roorkee has installed an Earthquake Early Warning (EEW) system  in Uttarakhand. The implemented EEW system was officially launched for the public on 4th August 2021, which has 167 acceleration sensors installed between MBT and MCT lines (85 sensors in Kumaun region and 82 sensors in Garhwal region), which continuously stream data to central server at IIT Roorkee, Roorkee. Further, 79 public sirens have been installed at various schools, hospitals, police stations, district emergency operation centre etc.  This system has recorded 57 earthquakes form June 2015 to July 2021. For the utilizing the benefits of this system a smart phone app has been launched for the public to alert public before the arrival of damaging waves. The operational system uses Allen (1982) modified STA/LTA algorithm for P-onset and Geiger’s grid search method is being used for calculating the location of the earthquake. It uses Pd parameter of 3 seconds for the magnitude determination. This system issues warning to the public, if calculated magnitude is greater than 5 and number of triggered stations is greater than 8. In this system sensors are being imported from Taiwan as there was no any Indian manufacturer, whereas sirens have been manufactured in EEW Lab, IIT Roorkee. For real time data processing “Earthworm” software is being used.  Smart phone app and warning dissemination program are written in house. As sensor are being imported from Taiwan, which make this system financially unviable to extend all over the Himalayan region and increase the density of the sensor. Further, a team in IIT Roorkee is also working on the development of low cost earthquake early warning system to reduce dependency on other countries.

NH-T5009 Superfast Modeling of Tsunami Propagation Using FPGA PC Board

Dr Andrey Marchuk %#+ Institute of Computational Mathematics and Mathematical Geophysics, Siberian Branch of the Russian Academy of Sciences, Russian Federation
Prof Mikhail Lavrentiev Institute of Automation and Electrometry SB RAS, Novosibirsk, Russian Federation
Dr Konstantin Oblaukhov Institute of Automation and Electrometry SB RAS, Novosibirsk, Russian Federation

The modern deep-ocean observation systems give possibility to estimate the tsunami source parameters before the leading wave reaches the shoreline. Then with the help of numerical modeling we need to calculate expected tsunami heights along the shoreline as soon as possible.  The field programmable gates array (FPGA) microchip is applied to achieve valuable performance gain calculating of tsunami wave propagation at modern regular personal computer. The two-step MacCormack difference scheme was used for numerical approximation of the nonlinear shallow water equations. After a number of numerical tests, the authors describe the idea of PC-based tsunami wave propagation simulation. Comparison of obtained results with the available analytic solutions shows the good enough precision of the developed software application. It takes less then 1 minute to compute 1 hour of the wave propagation (about 3600 time steps) in 3000 × 3000 nodes computation domain. The reliability was also sugZgested by the results comparison between the method proposed and the MOST software.

NH-T5014 Landslide Multi-Hazard Risk Assessment, Preparedness and Early Warning in South Asia Integrating Meteorology, Landscape and Society (LANDSLIP)

Prof Bruce D. Malamud %#+ King's College London, United Kingdom
Ms Emma Bee British Geological Survey, United Kingdom
Dr LANDSLIP CONSORTIUM http://www.landslip.org/, United Kingdom

LANDSLIP (Landslide multi-hazard risk assessment, preparedness and early warning in South Asia integrating meteorology, landscape and society) is a four-year research project funded by the UK NERC/FCDO SHEAR Programme (see web site URL www.landslip.org). LANDSLIP has produced a prototype early forecasting system for hydrologically controlled landslides in two areas of India with different geo-settings and meteorological regimes: Nilgiris (in the South), and Darjeeling (in the North). The aim is to achieve better landslide risk assessment and early forecasting in a multi-hazard framework. Our LANDSLIP system uses meteorological and landscape data and models that provide dynamic information on the likelihood of landslide occurrence and static landslide susceptibility of the territory. From these data and models, a prototype landslide forecast bulletin is compiled and delivered by the Indian Geological Survey (GSI) to the district authorities daily during the summer monsoon. Our system has been implemented in partnership with decision-makers in public and private sectors, academics, and not-for-profit agencies. By working with national and district authorities, LANDSLIP aims to increase resilience and reduction of loss from landslides. The project concept, results, and lessons learned in preparing a rainfall-induced landslide Early Forecasting system will be presented.

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NH-T6002 Independently Prepared Earthquake-induced Landslide Inventories Have Statistical and Geospatial Differences: a Case Study from the Gorkha Earthquake 2015, Nepal

Ms Badal Pokharel %#+ University of New South Wales, Australia
Mr Massimiliano Alvioli 2Istituto di Ricerca per la Protezione Idrogeologica, Consiglio Nazionale delle Ricerche, Italy
Mr Samsung Lim University of New South Wales, Australia

In this study, we compared five landslide inventories, prepared by independent researchers, in the aftermath of the 2015 Gorkha Earthquake, Nepal. To this end, we implemented a few comparison criteria: i) an error-index, to directly identify the cartographic mismatches among the inventories, ii) distribution of landslides, with respect to to the epicentre of the event and major geological thrust systems of the central Nepal Himalayan belt, iii) landslide susceptibility maps (LSM), obtained from each inventory using slope unit based logistic regression (LR) method, and iv) study of the differences among LSMs, applying geospatial techniques: hot spot analysis and cluster and outlier analysis. Results show significant differences among the landslides mapped for the same event, and derivative quantities. Performance of landslide susceptibility maps obtained from LR and geospatial analysis suggest an inventory with a greater number of landslides outperforms the inventory with a lesser number of landslides. The proposed statistical and geospatial approaches provide a novel framework to carry out quantitative comparisons of earthquake-triggered landslide inventories.

NH-T6003 Multi-hazard Interactions, Scenarios and Dynamic Risk: Two Case Study Cities of Nairobi and Istanbul

Prof Bruce D. Malamud %#+ King's College London, United Kingdom
Dr Joel Gill British Geological Survey, United Kingdom
Dr Robert Šakić Trogrlić King's College London, United Kingdom
Dr Ekbal Hussain British Geological Survey, United Kingdom
Dr Eser Cakti Kandilli Observatory, Turkey
Mr Aslihan Yolcu Boğaziçi University, Kandilli Observatory and Earthquake Research Institute, Turkey
Ms Emmah Mwangi Kenya Red Cross, Kenya
Dr Faith Taylor King's College London, United Kingdom

Global policy frameworks increasingly advocate for multi-hazard approaches across different spatial scales, whilst local management approaches are still informed by siloed single-hazard approaches. However, locations are often prone to multi-hazards. Different natural hazards and their interactions (e.g. earthquake triggering landslides), together with dynamic exposure and vulnerability, shape the disaster landscape of a given region and associated disaster impact.  Here, we discuss research done in the UK GCRF “Tomorrow’s Cities” Disaster Risk Hub, focusing on the urban poor in Istanbul, Kathmandu, Nairobi, and Quito. We first discuss the dynamic nature of risk through the lens of multi-hazard relationships and scenarios and in the context of two workshops (40 & 35 people) across the four cities.  Then, for Nairobi and Istanbul, we map the single natural hazardscape for both cities using evidence collected through peer-reviewed literature, grey literature, social media, newspapers and expert opinion. We classify 23 natural hazard types into geophysical, shallow process, meteorological, hydrological, climatological and extraterrestrial. We find for Nairobi 19, and Istanbul 22 of these 23 single hazard types had occurred or had the potential to occur. The breadth of single natural hazards that can potentially impact both Nairobi and Istanbul is much more extensive than usually considered by their hazard managers. We then use a global hazard matrix to identify possible hazard interactions, focusing on (i) hazard triggering secondary hazard, (ii) hazards amplifying the possibility of the secondary hazard occurring.  We identify 114 possible interactions for Nairobi and 73 for Istanbul and interaction cascade typologies that are typical for both cities (e.g. storm increasing probability of a flood which in turn triggers landslides). Our results indicate a breadth of natural hazards and their interactions in both Nairobi and Istanbul, and emphasise a need for a multi-hazard approach to disaster risk reduction and consideration of dynamic risk.

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NH-T7001 Role of Big Data in Understanding the Dynamics of Social Response to Natural Hazards

Prof Jonghun Kam %#+ Pohang University of Science and Technology, Korea, South

The utility of Big data with AI techniques in natural hazard mitigation and response has been examined in the Era of the 4th Industrial Revolution. Particularly, catastrophic natural hazards, such as earthquakes and droughts, stimulate multi-scale social responses. These multi-scale social responses to natural hazards depend mainly on the volume and accessibility of relevant information through mass and social media. Understanding the dynamics of social response to earthquakes will help how to diffuse public interest/awareness spatiotemporally and eventually improve the current natural hazard mitigation and response program. This poster will introduce recent pioneering studies that utilized the search activity volume data from Google Trends to understand the dynamics of social response to earthquakes and drought at the state, national, and global levels.

NH-T7003 Using Mobile Phone Technologies for Disaster Risk Management: Some Reflections from the Science for Humanitarian Emergencies and Resilience (SHEAR) Programme

Ms Emma Bee %#+ British Geological Survey, United Kingdom
Dr Mirianna Budimir Practical Action UK, United Kingdom
Dr Jonathan Paul Royal Holloway University, United Kingdom

Mobile technologies have been used throughout the Disaster Risk Management (DRM) cycle since the early 2000s. Whilst more attention is perhaps given to the more visible role of mobile phones in emergency response, for example, as a mechanism to capture and chronicle events as they unfold, they are also used to disseminate information, supporting emergency response teams to alert and locate those in danger.

With approximately 93% of the global population having access to a mobile broadband network and global smartphone connections doubling in just five years and rising sixfold in South Asia, there are growing opportunities for mobile technologies to be usefully harnessed in DRM. Yet many projects, especially mobile app developments, terminate after the proof-of concept-stage. Despite increasing coverage, lack of awareness, low levels of literacy and digital skills, and/or affordability, mean that approximately 51% of the population still do not use mobile internet, creating a ‘digital divide’. This
divide can be exacerbated in disaster contexts if mobile-enabled services are designed without appropriate consideration of end user needs.

In October 2020, the Science for Humanitarian Emergencies and Resilience (SHEAR) programme hosted a virtual workshop to explore the use of mobile technologies to support DRM. The breadth and depth of expertise and experience from workshop participants provided an opportunity to gather key learnings and examine common challenges and opportunities where mobile phone technologies could be usefully harnessed through different stages of the DRM lifecycle, and across different regions. This presentation will reflect on these workshop findings.