Monthly Archives: June 2016

CSU Phil-LiDAR 1 participated in the Caraga ICT Council’s Exhibit and Culmination Program

The Phil-LiDAR 1 project of Caraga State University (CSU) participated in the exhibit and culmination program of Caraga ICT (Information and Communications Technology) Council in celebration of ICT month last June 30, 2016 at the Atrium of Robinson’s Place in Butuan City. The program goes with the theme “ICT, Susi sa Kinabukasan” which showcases digital solutions, technology advancement, software and mobile application development as the key for social and economic progress. It was attended by several schools and institutions within Caraga Region.

The project's banner/poster shown during the exhibit

The project’s banner/poster shown during the exhibit

Mr. Elbert S. Moyon pays attention to the student’s queries and answers them.

Mr. Elbert S. Moyon pays attention to the student’s queries and answers them.

Mr. Edsel Matt O. Morales explains Flood EViDEns as the participant listens

Mr. Edsel Matt O. Morales explains Flood EViDEns as the participant listens

The Project sent two personnel namely, Mr. Edsel Matt O. Morales and Mr. Elbert S. Moyon, to exhibit ICT related programs/applications of the project during the said event. They showcased Flood EViDEns (Flood Event Visualization and Damage Estimations) – a web-based application for flood disaster management, in the project’s booth.

Several other project teams of CSU also participated and exhibited in the said event such as the FARMS of the ICT Center and the CLAIMS-GIS and CSU Phil-LIDAR 2 Projects of the College of Engineering and Information Technology.

Assessing the impacts of flooding caused by extreme rainfall events through a combined geospatial and numerical modeling approach

By Jojene R. Santillan, Arthur M. Amora, Meriam Makinano-Santillan, Jennifer T. Marqueso, Linbert C. Cutamora, Jesiree L. Serviano, Ronald M. Makinano

ABSTRACT:

In this paper, we present a combined geospatial and two dimensional (2D) flood modeling approach to assess the impacts of flooding due to extreme rainfall events. We developed and implemented this approach to the Tago River Basin in the province of Surigao del Sur in Mindanao, Philippines, an area which suffered great damage due to flooding caused by Tropical Storms Lingling and Jangmi in the year 2014. The geospatial component of the approach involves extraction of several layers of information such as detailed topography/terrain, man-made features (buildings, roads, bridges) from 1-m spatial resolution LiDAR Digital Surface and Terrain Models (DTM/DSMs), and recent land-cover from Landsat 7 ETM+ and Landsat 8 OLI images. We then used these layers as inputs in developing a Hydrologic Engineering Center Hydrologic Modeling System (HEC HMS)-based hydrologic model, and a hydraulic model based on the 2D module of the latest version of HEC River Analysis System (RAS) to dynamically simulate and map the depth and extent of flooding due to extreme rainfall events. The extreme rainfall events used in the simulation represent 6 hypothetical rainfall events with return periods of 2, 5, 10, 25, 50, and 100 years. For each event, maximum flood depth maps were generated from the simulations, and these maps were further transformed into hazard maps by categorizing the flood depth into low, medium and high hazard levels. Using both the flood hazard maps and the layers of information extracted from remotely-sensed datasets in spatial overlay analysis, we were then able to estimate and assess the impacts of these flooding events to buildings, roads, bridges and landcover. Results of the assessments revealed increase in number of buildings, roads and bridges; and increase in areas of land-cover exposed to various flood hazards as rainfall events become more extreme. The wealth of information generated from the flood impact assessment using the approach can be very useful to the local government units and the concerned communities within Tago River Basin as an aid in determining in an advance manner all those infrastructures (buildings, roads and bridges) and land-cover that can be affected by different extreme rainfall event flood scenarios.

KEYWORDS:  Extreme rainfall, Flooding, Impact assessment, 2D Flood modeling, LiDAR, Landsat


Publication Details/Metadata:

Paper Title: AASSESSING THE IMPACTS OF FLOODING CAUSED BY EXTREME RAINFALL EVENTS THROUGH A COMBINED GEOSPATIAL AND NUMERICAL MODELING APPROACH

Authors: Jojene R. Santillan, Arthur M. Amora, Meriam Makinano-Santillan, Jennifer T. Marqueso, Linbert C. Cutamora, Jesiree L. Serviano, Ronald M. Makinano

Publication Date: 2016

Conference Name/Journal/Book Title: ISPRS – International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences

Volume: XLI-B8

Pages: 1271-1278

Publisher: International Society for Photogrammetry and Remote Sensing (ISPRS), Copernicus GmbH

Link to Full Text: View/Download from: ISPRS Website or CCGeo.Info Website

Academe-local government partnership towards effective application of geospatial technologies for smarter flood disaster management at the local level: an example from Mindanao, Philippines

By Meriam Makinano-Santillan, Jojene R. Santillan, Edsel Matt O. Morales, Lorie Cris S. Asube, Arthur M. Amora, Linbert C. Cutamora, Ronald. M. Makinano

ABSTRACT:

In this paper, we discuss how an academe-local government partnership can lead the way for the effective use of geospatial technologies for smarter and geospatially-informed decision making before, during, and after a flood disaster. In Jabonga municipality, in the province of Agusan del Norte, in Mindanao, Philippines, two significant flooding events occurred in the year 2014 which were caused by overflowing water bodies due to continuous heavy rains. These flood events inundated populated areas, caused massive evacuation, made roads un-passable, and greatly damaged sources of incomes such as croplands and other agricultural areas. The partnership between Caraga State University and the local government of Jabonga attempts to improve localized flood disaster management through the development of web-based Near-real Time Flood Event Visualization and Damage Estimations (Flood EViDEns) application. Flood EViDENs utilizes LiDAR-derived elevation and information products as well as other elevation datasets, water level records by monitoring stations, flood simulation models, flood hazard maps, and socio-economic datasets (population, household information, etc.), in order to visualize in near-real time the current and future extent of flooding, to disseminate early warnings, and to provide maps and statistics of areas and communities affected and to be affected by flooding. The development of Flood EViDEns as the main product of the partnership is an important application of geospatial technologies that will allow smarter and geospatially-informed decision making before, during, and after a flood disaster in Jabonga.

KEYWORDS:  Geospatial technology, Flood, Disaster management, Academe-local government partnership, Mindanao, Philippines


Publication Details/Metadata:

Paper Title: ACADEME-LOCAL GOVERNMENT PARTNERSHIP TOWARDS EFFECTIVE APPLICATION OF GEOSPATIAL TECHNOLOGIES FOR SMARTER FLOOD DISASTER MANAGEMENT AT THE LOCAL LEVEL: AN EXAMPLE FROM MINDANAO, PHILIPPINES

Authors: Meriam Makinano-Santillan, Jojene R. Santillan, Edsel Matt O. Morales, Lorie Cris S. Asube, Arthur M. Amora, Linbert C. Cutamora, Ronald. M. Makinano

Publication Date: 2016

Conference Name/Journal/Book Title: ISPRS – International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences

Volume: XLI-B8

Pages: 109-115

Publisher: International Society for Photogrammetry and Remote Sensing (ISPRS), Copernicus GmbH

Link to Full Text: View/Download from: ISPRS Website or CCGeo.Info Website

Vertical accuracy assessment of 30-m resolution ALOS, ASTER, and SRTM global DEMs over northeastern Mindanao, Philippines

By Jojene R. Santillan, Meriam Makinano-Santillan

ABSTRACT:

The ALOS World 3D – 30 m (AW3D30), ASTER Global DEM Version 2 (GDEM2), and SRTM-30 m are Digital Elevation Models (DEMs) that have been made available to the general public free of charge. An important feature of these DEMs is their unprecedented horizontal resolution of 30-m and almost global coverage. The very recent release of these DEMs, particularly AW3D30 and SRTM- 30 m, calls for opportunities for the conduct of localized assessment of the DEM’s quality and accuracy to verify their suitability for a wide range of applications in hydrology, geomorphology, archaelogy, and many others. In this study, we conducted a vertical accuracy assessment of these DEMs by comparing the elevation of 274 control points scattered over various sites in northeastern Mindanao, Philippines. The elevations of these control points (referred to the Mean Sea Level, MSL) were obtained through 3rd order differential levelling using a high precision digital level, and their horizontal positions measured using a global positioning system (GPS) receiver. These control points are representative of five (5) land-cover classes namely brushland (45 points), built-up (32), cultivated areas (97), dense vegetation (74), and grassland (26). Results showed that AW3D30 has the lowest Root Mean Square Error (RMSE) of 5.68 m, followed by SRTM-30 m (RMSE = 8.28 m), and ASTER GDEM2 (RMSE = 11.98 m). While all the three DEMs overestimated the true ground elevations, the mean and standard deviations of the differences in elevations were found to be lower in AW3D30 compared to SRTM-30 m and ASTER GDEM2. The superiority of AW3D30 over the other two DEMS was also found to be consistent even under different landcover types, with AW3D30’s RMSEs ranging from 4.29 m (built-up) to 6.75 m (dense vegetation). For SRTM-30 m, the RMSE ranges from 5.91 m (built-up) to 10.42 m (brushland); for ASTER GDEM2, the RMSE ranges from 9.27 m (brushland) to 14.88 m (dense vegetation). The results of the vertical accuracy assessment suggest that the AW3D30 is more accurate than SRTM-30 m and ASTER GDEM2, at least for the areas considered in this study. On the other hand, the tendencies of the three DEMs to overestimate true ground elevation can be considered an important finding that users of the DEMs in the Philippines should be aware of, and must be considered into decisions regarding use of these data products in various applications.

KEYWORDS:  AW3D30, ASTER GDEM2, SRTM-30m, Digital Elevation Model, Accuracy Assessment, Philippines


Publication Details/Metadata:

Paper Title: VERTICAL ACCURACY ASSESSMENT OF 30-M RESOLUTION ALOS, ASTER, AND SRTM GLOBAL DEMS OVER NORTHEASTERN MINDANAO, PHILIPPINES

Authors: Jojene R. Santillan, Meriam Makinano-Santillan

Publication Date: 2016

Conference Name/Journal/Book Title: ISPRS – International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences

Volume: XLI-B4

Pages: 149-156

Publisher: International Society of Photogrammetry and Remote Sensing (ISPRS)

Link to Full Text: View/Download from: ISPRS Website or CCGeo.Info Website