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Analysis of full-waveform pulses from space-based laser altimeter systems are expected to improve our ability of measuring forests globally. Moreover, with the increase in the number of waveform data sets, it is now possible to study temporal changes in waveform returns over the same spatial domain. ICESat full waveform data from two epochs, i.e. winter and summer (2003) along nearcoincident ground tracks, are studied. Data analysis methods are discussed, including normalization and matching of near-coincident waveforms, Gaussian decomposition, and derivation of forest measurement and forest change parameters. We quantify differences between winter and summer waveforms, acquired over broad-leaved, mixed-wood, and needle-leaved forests in Europe. The results indicate that, although maximum tree height barely changes over six months, i.e. ,2.2% for all three cover types, the Height of Median Energy (HOME) changed most in broad-leaved (a 148% change) and least for conifers (a 36% change, winter to summer). Ratios of ground energy to canopy energy of normalized waveforms also changed noticeably over time: 67% in broad-leaved, 62% in mixed-wood, and 47% in conifers. Attempts are made to differentiate and classify these three cover types on the basis of these and other canopy metrics. The initial results, with a coefficient k of agreement between reference and classified data of 0.57, provide a baseline against which improvements in data and methodology can be gauged.

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The 2nd international summer school “Close-range sensing techniques in Alpine terrain” was held in July 2017 in Obergurgl, Austria. Participants were trained in selected close-range sensing methods, such as photogrammetry, laser scanning and thermography. The program included keynotes, lectures and hands-on assignments combining field project planning, data acquisition, processing, quality assessment and interpretation. Close-range sensing was applied for different research questions of environmental monitoring in high mountain environments, such as geomorphologic process quantification, natural hazard management and vegetation mapping. The participants completed an online questionnaire evaluating the summer school, its content and organisation, which helps to improve future summer schools.

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