GeoWorld

GeoWorld January 2012

Issue link: https://read.dmtmag.com/i/53167

Contents of this Issue

Navigation

Page 22 of 31

datasets over large areas with one flight and obtain sub-meter resolution. Integrated sensor platforms provide an unmatched level of temporal cohesion, strengthening the qual- ity, value and applicability of data. These datasets are a veritable gold mine of information with a broad range of applications for climate-change adaptation planning, including inundation studies, glacier map- ping, disaster-response planning, agricultural stud- ies, rainwater management, vegetation studies and energy planning. Figure 1. Bowker Creek experienced flooding on the morning of Dec. 12, 2010, following a "1 in 10-year" 24-hour storm event. "During a rainfall event, it's very likely that an event like that could happen again," said David Marshall, director of engineering services for the District of Oak Bay. "With all the upstream development, it probably won't get any better." Climate-Change Uncertainty The flooding issues experienced in the Bowker Creek Watershed aren't unique and aren't the only set of problems facing the community. One such problem the community faces in dealing with the effects of a chang- ing climate is the same problem faced by any other populated center on the globe: uncertainty. Whether current changes in climate are anthropo- genically (human) induced or not, climate change is occurring and has always occurred. However, because climate-change science is complex and based on mul- tiple future scenarios, the variables are endless and the outcomes uncertain. So the question that should be debated is how can resources be allocated in the best way to increase adaptive capacity? To hedge bets against uncertainty, measures designed to increase our adaptive capacity and resil- ience to future climates should provide immediate ben- efit to the present. Integrated airborne remote sensing provides data that support intelligent planning on how to best prepare communities for future climates (i.e., climate-change adaptation planning). The vast potential of light detection and ranging (LIDAR) and other airborne remotely sensed data has just begun to be explored by industry outsiders, espe- cially in new applications relating to climate-change adaptation planning. With modern remote-sensing plat- forms such as The University of Victoria's Integrated ASIA Dual-Channel hyperspectral, thermal, digital imag- ing and LIDAR system, it's possible to collect multiple Imagery/LIDAR Special Issue Rainwater Management One of the most-common applications of LIDAR data is to generate a bare-Earth digital elevation model (DEM). Accurate 3-D ground models rapidly created from LIDAR have applications in large-scale floodplain hydraulic modeling and also are used to examine micro-topographic relief for detailed rainwater-runoff analyses (see Figure 2). Bare-Earth LIDAR data can be used to trace pollution and help locate suitable areas for onsite low-impact development rainwater- management facilities, such as rain gardens and "green roofs." Delineating micro-catchment areas within impervi- ous sites can help identify suitable sites for infiltration areas and can support detailed hydraulic modeling to satisfy engineering-performance standards. Peak flow rates and total runoff volumes can be accurately cal- culated for many small sites over a large area using a LIDAR-based DEM. Airborne LIDAR is an efficient method of macro data collection, but the data are applicable at the micro scale. Figure 2. Micro catchments on one site are delineated with LIDAR drainage vectors, which can be used to estimate runoff volumes and pollution loads at individual infiltration points. JANUAR Y 2O12 / WWW . GEOPLA CE . COM 23

Articles in this issue

Archives of this issue

view archives of GeoWorld - GeoWorld January 2012