Icesat full waveform altimetry compared to airborne laser altimetry over the Netherlands

Since 2003 the spaceborne laser altimetry system on board of NASA’s Ice, Cloud and land Elevation Satellite (ICESat) has acquired a large world-wide database of full waveform data organized in 15 products. In this research three products are evaluated over The Netherlands. For this purpose the raw full waveform product, the derived Gaussian decomposition product and the global land evaluation product are compared to laser data from the Dutch national airborne laser altimetry archive AHN. Using the CORINE land cover 2000 database allows us to compare ICESat to AHN elevation profiles with respect to the land cover classes forest, urban, bare land/low vegetation and water. This comparison shows that a large average height difference of 5.7 m occurs over forest, while much smaller differences of 1.24 m over urban areas, of 0.43 m over bare land/low vegetation and of 0.07 m over water are found. The reason for this large difference over forests is that the standard processing of NASA does not take the position of the last Gaussian mode of the waveform into account. Incorporating results from a full waveform processing procedure allows us to determine improved ICESat profiles. Comparing the improved profiles shows that the average difference with the AHN profiles over forest is reduced to -0.38 m, while the average differences for the other land cover classes do not exceed -0.75 m. Encountered limitations are discussed in the conclusions.Remote SensingAerospace Engineerin

ICESat Full-Waveform Altimetry Compared to Airborne Laser Scanning Altimetry Over The Netherlands

Since 2003, the full-waveform laser altimetry system onboard NASA's Ice, Cloud and land Elevation Satellite (ICESat) has acquired a worldwide elevation database. ICESat data are widely applied for change detection of ice sheet mass balance, forest structure estimation, and digital terrain model generation of remote areas. ICESat's measurements will be continued by a follow-up mission. To fully assess the application possibilities of the full-waveform products of these missions, this research analyzes the vertical accuracy of ICESat products over complex terrain with respect to land cover type. For remote areas, validation of individual laser shots is often beyond reach. For a country with extensive geo-infrastructure such as The Netherlands, excellent countrywide validation is possible. Therefore, the ICESat full-waveform product GLA01 and the land elevation product GLA14 are compared to data from the Dutch airborne laser altimetry archive Actual Height model of the Netherlands (AHN). For a total population of 3172 waveforms, differences between ICESat- and AHN-derived terrain heights are determined. The average differences are below 25 cm over bare land and urban areas. Over forests, differences are even smaller but with slightly larger standard deviations of about 60 cm. Moreover, a waveform-based feature height comparison resulted in feature height differences of 1.89 m over forest, 1.48 m over urban areas, and 29 cm over low vegetation. These results, in combination with the presented processing chain and individual waveform examples, show that state-of-the-art ICESat waveform processing is able to analyze waveforms at the individual shot level, particularly outside urban areas.Remote SensingAerospace Engineerin

EuroSDR: The pan european network for mapping agencies and academia

EuroSDR (http://www.eurosdr.net/) is a non-profit organisation that provides a pan-European network that brings together mapping / cadastre agencies and academia for the purpose of applied research, and securing timely, research-based knowledge that allows the agencies to play their role as content providers and government competence centres for geographic information and spatial data infrastructures. EuroSDR is the recognised provider of research-based knowledge to a Europe where citizens can readily benefit from geographic information. Its mission is to develop and improve methods, systems and standards for the acquisition, processing, production, maintenance, management, visualization, and dissemination of geographic reference data in support of applications and service delivery. EuroSDR delivers advanced research-based knowledge. Its value is generated by facilitating interaction between research organisations and the public and private sector with the aim of exchanging ideas and knowledge about relevant research topics; by facilitating and contributing to research projects; and by transferring knowledge and research results to real world applications. The paper gives an overview about EuroSDR research principles, research alliances, objectives and action plans of each of the technical commissions. Urban Data Scienc