A new 1 km digital elevation model of Antarctica derived from combined radar and laser data – Part 2: Validation and error estimates
Author:
Griggs J. A.,Bamber J. L.
Abstract
Abstract. We have developed a new digital elevation model (DEM) of Antarctica from a combination of satellite radar and laser altimeter data. Here, we assess the accuracy of the DEM by comparison with airborne altimeter data from four campaigns covering a wide range of surface slopes and ice sheet regions. RMS differences varied from 4.84 m, when compared to a densely gridded airborne dataset over the Siple Coast region of West Antarctica to 29.28 m when compared to a more limited dataset over the Antarctic Peninsula where surface slopes are high and the across track spacing of the satellite data is relatively large. The airborne data sets were employed to produce an error map for the DEM by developing a multiple linear regression model based on the variables known to influence errors in the DEM. Errors were found to correlate highly with surface slope, roughness and density of satellite data points. Errors ranged from typically ~1 m over the ice shelves to between about 4 and 10 m for the majority of the grounded ice sheet. In the steeply sloping margins, along the Peninsula and mountain ranges the estimated error is several tens of metres. Slightly less than 7% of the area covered by the satellite data had an estimated random error greater than 20 m.
Publisher
Copernicus GmbH
Reference18 articles.
1. Bamber, J. and Gomez-Dans, J. L.: The accuracy of digital elevation models of the Antarctic continent, Earth Planet. Sc. Lett., 237, 516–523, 2005. 2. Bamber, J. L. and Bindschadler, R. A.: An improved elevation dataset for climate and ice-sheet modelling: validation with satellite imagery, Ann. Glaciol., 25, 439–444, 1997. 3. Bamber, J. L., Gomez-Dans, J. L., and Griggs, J. A.: A new 1 km digital elevation model of Antarctica derived from combined radar and laser data – Part~1: Data and methods, The Cryosphere, 5, 811–841, 2008. 4. Blankenship, D. D., Morse, D., Finn, C. A., Bell, R. A., Peters, M. E., Kempf, S. D., Hodge, S. M., Studinger, M., Behrendt, J. C., and Brozena, J. M.: Geologic controls on the initiation of rapid basal motion for West Antarctic ice streams: A geophysical perspective including new airborne radar sounding and laser altimetry results, in: The West Antarctic Ice Sheet, Behavior and Environment, edited by: Alley, R. B. and Bindschadler, R. A., American Geophysical Union, 105–121, 2001. 5. Brenner, A. C., DiMarzio, J. R., and Zwally, H. J.: Precision and accuracy of satellite radar and laser altimeter data over the continental ice sheets, IEEE T. Geosci. Remote, 45, 321–331, https://doi.org/310.1109/TGRS.2006.887172, 2007.
Cited by
2 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|