Visualizing Sea Level Rise in Navotas by GIS and Terrain Modeling


Gerald A Galgana, Sergio C Abad II, Jose Ramon T Villarin, S.J. , May Celine TM Vicente
Vol 7 No 1 (2004), pp.

 

Abstract:

 

Flooding due to sea level rise is a primary concern brought about by climate change. This study focuses on northern Navotas, Metro Manila, a densely populated urban area affected by frequent diurnal changes in sea level. The study verifies terrain data vis-à-vis its vulnerability to water level rise using Geographic Information System (GIS) and 3D Terrain Modeling-Visualization software. The research introduces a method to evaluate vulnerability and predict how such change in sea level will spatially affect a certain locality. The primary objective is to provide a three-dimensional visualization technique that will integrate geospatial data with possible changes in sea level. Topographic information is linked with planimetric data from existing maps and aerial photography. Visualizations of several levels of increase, at 0.25-meter intervals are presented, with political boundary overlays, selected buildings and aerial images. Results are then compared with demographic data and affected population is deduced. Based on one simulation result, about 96.49 hectares within the 200-hectare study area will be affected by a 1-meter rise in sea level, with 54,145 individuals affected. Limited ground truthing during a high tide event verified some of the predicted submergence along the main roads. The high-resolution simulation presented by the study provides an effective means to visually and spatially assess the extent of topographic vulnerabilities of a locality to possible sea level change, and may help communities plan effectively for such events.

 

Keywords: sea level rise, terrain modelling, Geographic Information System (GIS)