Use of Lidar in Environmental Science

by

Adrian Harpold

• LAST REVIEWED: 26 October 2015
• LAST MODIFIED: 26 October 2015
• DOI: 10.1093/obo/9780199363445-0039

Introduction

Light detection and ranging (lidar) is a technology that allows construction of three-dimensional surfaces. Lidar systems emit energy, usually in the near-infrared wavelength, and measure the travel time before receiving that energy back at a sensor, thus allowing discrete (individual points) or continuous (full waveform) representation of the land surface structure. Depending on the application, lidar allows simultaneous measurement of topography, aboveground vegetation, human infrastructure, and snow/ice at landscape scales (>1000 km²) and fine resolutions (<10 cm). Lidar measurement units can be mounted on aerial platforms (often referred to as airborne laser scanning [ALS] or airborne laser swath mapping [ALSM]), terrestrial platforms (terrestrial laser scanning [TLS]), and space-borne platforms. Flexibility in application platforms, rapid advancements in instrument technology, and fusion with other remote sensing technologies (e.g. hyperspectral imaging) and ground observations has made lidar technology attractive for a variety of research applications. Specifically, the concomitant measurement of the geosphere, ecosphere, and hydrosphere is revolutionizing our ability to answer foundational, interdisciplinary questions in the Earth sciences. Lidar is being applied to characterize extreme geomorphic events as well as landscape evolution and soil development in response to biotic and climatic forcings. The characterization of vegetation structure and species identification is advancing forest and rangeland resource management, carbon estimation, and habitat characterization. Water penetrating lidar systems allow mapping of bathymetry and investigations into aquatic habitat. Lidar has numerous applications within cryospheric science, ranging from seasonal snowpack characterization to glaciology and sea ice. Similarly, lidar offers multiple avenues to advance hydrological science through our understanding of surface water hydraulics, process and feature identification, and quantifying interactions between the land surface and atmosphere. Although lidar technology has been available commercially since the 1990s, many of the important advancements related to environmental science have occurred since 2005. The references cited in this article focus on a diversity of applications using lidar in environmental science and the reader should note a technical background might be necessary to understand many of these topics. Introductory material found in the general overviews can serve as a foundation for the more detailed applications described later.

General Overviews

The works cited in this section give overview information on a single topic or more broadly across varying lidar applications. Shan and Toth 2008 and Vosselman and Maas 2010 provide a range of introductory and focused methodological information that give background for non-initiated lidar users. Readers are directed to more focused overviews on forest applications of lidar (Maltamo, et al. 2014), cryosphere applications (Deems, et al. 2013), and geomorphological and archaeological applications (Glennie, et al. 2013 and Tarolli 2014). These texts provide more approachable and broad information on lidar applications than the research papers referenced in the next section.

• Deems, J. S., T. H. Painter, and D. C. Finnegan. 2013. Lidar measurement of snow depth: A review. Journal of Glaciology 59.215: 467–479.

  DOI: 10.3189/2013JoG12J154

  The most comprehensive review of lidar applications to cryospheric science, with a particular focus on seasonal snow cover. Reviews lidar methodologies, potential errors unique to snow surface lidar applications, and includes recommendations for snow-based projects using lidar. This is an important reference for those applying lidar in snow-covered areas.

• Glennie, C. L., W. E. Carter, R. L. Shrestha, and W. E. Dietrich. 2013. Geodetic imaging with airborne LiDAR: The earth’s surface revealed. Reports on Progress in Physics 76.8: 086801.

  DOI: 10.1088/0034-4885/76/8/086801

  The authors present a current state of the science on airborne lidar and illustrate these advances with several case studies in tectonics, landscape evolution, and landslides. The authors also present an outline for coming advances in airborne lidar made possible by full waveform systems, multispectral lidar, and new platforms. An excellent reference for those primarily interested in the use of bare-earth lidar-derived products. The text is appropriate for undergraduate students and has compelling figures.

• Maltamo, M., E. Næsset, and J. Vauhkonen, eds. 2014. Forestry applications of airborne laser scanning. Dordrecht, The Netherlands: Springer..

  DOI: 10.1007/978-94-017-8663-8

  An overview of lidar technologies focused on applications to forest inventory characterization and forest ecosystem science using airborne lidar. The first third of the book addresses methodological issues, such as application of full waveform lidar, tree segmentation, integration with optical sensors, and extracting tree-level information. The remainder of the book includes case studies. The book provides an excellent reference on forestry applications and introductory material for those new to lidar.

• Shan, J., and C. K. Toth. 2008. Topographic laser ranging and scanning: Principles and processing. 2008. Boca Raton, FL: CRC.

  DOI: 10.1201/9781420051438

  An excellent reference on the technical details of terrestrial, airborne, and space-borne lidar applications. Includes information on the hardware and important consideration for calibrating and georeferencing lidar data sets, as well as assessing its accuracy and quality. Also includes limited examples of lidar applications. A reference volume for those focused on the technical aspects of lidar data collection and processing.

• Tarolli, P. 2014. High-resolution topography for understanding earth surface processes: Opportunities and challenges. Geomorphology 216:295–312.

  DOI: 10.1016/j.geomorph.2014.03.008

  A review of recent applications of lidar-derived topography to understand geomorphic processes in natural and engineered landscapes. The author reviews lidar’s utility for natural hazard mapping, channel mapping, river morphology, tectonics, and engineered landscape flow routing and road network delineation. A discussion of emerging fields and technologies is also presented. This is an approachable review of the current state of lidar in geomorphic investigations.

• Vosselman, G. V., and H. G. Maas. 2010. Airborne and terrestrial laser scanning. Boca Raton, FL: CRC.

  A comprehensive general reference on the technical, operational, and applied aspects of lidar, with a greater focus on airborne laser scanning applications. The authors cover a wide range of topics, including organization and visualization of point clouds, calibration and registration of data, and application to forestry, built environments, and archaeology. The text is geared to a more advanced reader at the graduate student or working professional level. The most comprehensive reference on lidar.