Articles | Volume 7, issue 4
https://doi.org/10.5194/gi-7-277-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gi-7-277-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Oct 2018
Research article |
| 15 Oct 2018
| 15 Oct 2018
Precise DEM extraction from Svalbard using 1936 high oblique imagery
Department of Geosciences, University of Oslo, Postboks 1047 Blindern, 0316 Oslo, Norway
Niels Ivar Nielsen
Department of Geosciences, University of Oslo, Postboks 1047 Blindern, 0316 Oslo, Norway
Frédérique Couderette
Department of Geosciences, University of Oslo, Postboks 1047 Blindern, 0316 Oslo, Norway
École Nationale des Sciences Géographiques, 6 et 8 Avenue Blaise Pascal,
Cité Descartes, 77420 Champs-sur-Marne, France
Christopher Nuth
Department of Geosciences, University of Oslo, Postboks 1047 Blindern, 0316 Oslo, Norway
Andreas Kääb
Department of Geosciences, University of Oslo, Postboks 1047 Blindern, 0316 Oslo, Norway
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Revised manuscript not accepted
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Paul Willem Leclercq, Andreas Kääb, and Bas Altena
The Cryosphere, 15, 4901–4907, https://doi.org/10.5194/tc-15-4901-2021, https://doi.org/10.5194/tc-15-4901-2021, 2021
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In this study we present a novel method to detect glacier surge activity. Surges are relevant as they disturb the link between glacier change and climate, and studying surges can also increase understanding of glacier flow. We use variations in Sentinel-1 radar backscatter strength, calculated with the use of Google Earth Engine, to detect surge activity. In our case study for the year 2018–2019 we find 69 cases of surging glaciers globally. Many of these were not previously known to be surging.
Andreas Kääb, Mylène Jacquemart, Adrien Gilbert, Silvan Leinss, Luc Girod, Christian Huggel, Daniel Falaschi, Felipe Ugalde, Dmitry Petrakov, Sergey Chernomorets, Mikhail Dokukin, Frank Paul, Simon Gascoin, Etienne Berthier, and Jeffrey S. Kargel
The Cryosphere, 15, 1751–1785, https://doi.org/10.5194/tc-15-1751-2021, https://doi.org/10.5194/tc-15-1751-2021, 2021
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Hardly recognized so far, giant catastrophic detachments of glaciers are a rare but great potential for loss of lives and massive damage in mountain regions. Several of the events compiled in our study involve volumes (up to 100 million m3 and more), avalanche speeds (up to 300 km/h), and reaches (tens of kilometres) that are hard to imagine. We show that current climate change is able to enhance associated hazards. For the first time, we elaborate a set of factors that could cause these events.
Andreas Kääb, Tazio Strozzi, Tobias Bolch, Rafael Caduff, Håkon Trefall, Markus Stoffel, and Alexander Kokarev
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We present a map of rock glacier motion over parts of the northern Tien Shan and time series of surface speed for six of them over almost 70 years.
This is by far the most detailed investigation of this kind available for central Asia.
We detect a 2- to 4-fold increase in rock glacier motion between the 1950s and present, which we attribute to atmospheric warming.
Relative to the shrinking glaciers in the region, this implies increased importance of periglacial sediment transport.
Andreas Alexander, Jaroslav Obu, Thomas V. Schuler, Andreas Kääb, and Hanne H. Christiansen
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L. Girod and S. Filhol
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Andreas Alexander, Maarja Kruusmaa, Jeffrey A. Tuhtan, Andrew J. Hodson, Thomas V. Schuler, and Andreas Kääb
The Cryosphere, 14, 1009–1023, https://doi.org/10.5194/tc-14-1009-2020, https://doi.org/10.5194/tc-14-1009-2020, 2020
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This work shows the potential of pressure and inertia sensing drifters to measure flow parameters along glacial channels. The technology allows us to record the spatial distribution of water pressures, as well as an estimation of the flow velocity along the flow path in the channels. The measurements show a high repeatability and the potential to identify channel morphology from sensor readings.
Jaroslav Obu, Sebastian Westermann, Gonçalo Vieira, Andrey Abramov, Megan Ruby Balks, Annett Bartsch, Filip Hrbáček, Andreas Kääb, and Miguel Ramos
The Cryosphere, 14, 497–519, https://doi.org/10.5194/tc-14-497-2020, https://doi.org/10.5194/tc-14-497-2020, 2020
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The Cryosphere, 13, 3117–3137, https://doi.org/10.5194/tc-13-3117-2019, https://doi.org/10.5194/tc-13-3117-2019, 2019
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Désirée Treichler, Andreas Kääb, Nadine Salzmann, and Chong-Yu Xu
The Cryosphere, 13, 2977–3005, https://doi.org/10.5194/tc-13-2977-2019, https://doi.org/10.5194/tc-13-2977-2019, 2019
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Andreas Kääb, Bas Altena, and Joseph Mascaro
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B. Altena, O. N. Haga, C. Nuth, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-2-W13, 1723–1727, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, https://doi.org/10.5194/isprs-archives-XLII-2-W13-1723-2019, 2019
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The Cryosphere, 13, 997–1004, https://doi.org/10.5194/tc-13-997-2019, https://doi.org/10.5194/tc-13-997-2019, 2019
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In March 2007, the Leñas Glacier in the Central Andes of Argentina collapsed and released an ice avalanche that travelled a distance of 2 km. We analysed aerial photos, satellite images and field evidence to investigate the evolution of the glacier from the 1950s through the present day. A clear potential trigger of the collapse could not be identified from available meteorological and seismic data, nor could a significant change in glacier geometry leading to glacier instability be detected.
Robert McNabb, Christopher Nuth, Andreas Kääb, and Luc Girod
The Cryosphere, 13, 895–910, https://doi.org/10.5194/tc-13-895-2019, https://doi.org/10.5194/tc-13-895-2019, 2019
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Estimating glacier changes involves measuring elevation changes, often using elevation models derived from satellites. Many elevation models have data gaps (voids), which affect estimates of glacier change. We compare 11 methods for interpolating voids, finding that some methods bias estimates of glacier change by up to 20 %, though most methods have a smaller effect. Some methods produce reliable results even with large void areas, suggesting that noisy elevation data are still useful.
Bas Altena, Ted Scambos, Mark Fahnestock, and Andreas Kääb
The Cryosphere, 13, 795–814, https://doi.org/10.5194/tc-13-795-2019, https://doi.org/10.5194/tc-13-795-2019, 2019
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Many glaciers in southern Alaska and the Yukon experience changes in flow speed, which occur in episodes or sporadically. These flow changes can be measured with satellites, but the resulting raw velocity products are messy. Thus in this study we developed an automatic method to produce a synthesized velocity product over a large glacier region of roughly 600 km by 200 km. Velocities are at a monthly resolution and at 300 m resolution, making all kinds of glacier dynamics observable.
Katrin Lindbäck, Jack Kohler, Rickard Pettersson, Christopher Nuth, Kirsty Langley, Alexandra Messerli, Dorothée Vallot, Kenichi Matsuoka, and Ola Brandt
Earth Syst. Sci. Data, 10, 1769–1781, https://doi.org/10.5194/essd-10-1769-2018, https://doi.org/10.5194/essd-10-1769-2018, 2018
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Tidewater glaciers terminate directly into the sea and the glacier fronts are important feeding areas for birds and marine mammals. Svalbard tidewater glaciers are retreating, which will affect fjord circulation and ecosystems when glacier fronts end on land. In this paper, we present digital maps of ice thickness and topography under five tidewater glaciers in Kongsfjorden, northwestern Svalbard, which will be useful in studies of future glacier changes in the area.
Adrien Gilbert, Silvan Leinss, Jeffrey Kargel, Andreas Kääb, Simon Gascoin, Gregory Leonard, Etienne Berthier, Alina Karki, and Tandong Yao
The Cryosphere, 12, 2883–2900, https://doi.org/10.5194/tc-12-2883-2018, https://doi.org/10.5194/tc-12-2883-2018, 2018
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In Tibet, two glaciers suddenly collapsed in summer 2016 and produced two gigantic ice avalanches, killing nine people. This kind of phenomenon is extremely rare. By combining a detailed modelling study and high-resolution satellite observations, we show that the event was triggered by an increasing meltwater supply in the fine-grained material underneath the two glaciers. Contrary to what is often thought, this event is not linked to a change in the thermal condition at the glacier base.
Martina Barandun, Matthias Huss, Ryskul Usubaliev, Erlan Azisov, Etienne Berthier, Andreas Kääb, Tobias Bolch, and Martin Hoelzle
The Cryosphere, 12, 1899–1919, https://doi.org/10.5194/tc-12-1899-2018, https://doi.org/10.5194/tc-12-1899-2018, 2018
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Chiyuki Narama, Mirlan Daiyrov, Murataly Duishonakunov, Takeo Tadono, Hayato Sato, Andreas Kääb, Jinro Ukita, and Kanatbek Abdrakhmatov
Nat. Hazards Earth Syst. Sci., 18, 983–995, https://doi.org/10.5194/nhess-18-983-2018, https://doi.org/10.5194/nhess-18-983-2018, 2018
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Four large drainages from glacial lakes occurred during 2006–2014 in the western Teskey Range, Kyrgyzstan. These floods caused extensive damage, killing people and livestock, as well as destroying property and crops. Due to their subsurface outlet, we refer to these short-lived glacial lakes as being of the
tunnel-type, a type that drastically grows and drains over a few months.
Solveig H. Winsvold, Andreas Kääb, Christopher Nuth, Liss M. Andreassen, Ward J. J. van Pelt, and Thomas Schellenberger
The Cryosphere, 12, 867–890, https://doi.org/10.5194/tc-12-867-2018, https://doi.org/10.5194/tc-12-867-2018, 2018
B. Altena, A. Mousivand, J. Mascaro, and A. Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLII-3-W3, 7–11, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, https://doi.org/10.5194/isprs-archives-XLII-3-W3-7-2017, 2017
Johannes Jakob Fürst, Fabien Gillet-Chaulet, Toby J. Benham, Julian A. Dowdeswell, Mariusz Grabiec, Francisco Navarro, Rickard Pettersson, Geir Moholdt, Christopher Nuth, Björn Sass, Kjetil Aas, Xavier Fettweis, Charlotte Lang, Thorsten Seehaus, and Matthias Braun
The Cryosphere, 11, 2003–2032, https://doi.org/10.5194/tc-11-2003-2017, https://doi.org/10.5194/tc-11-2003-2017, 2017
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For the large majority of glaciers and ice caps, there is no information on the thickness of the ice cover. Any attempt to predict glacier demise under climatic warming and to estimate the future contribution to sea-level rise is limited as long as the glacier thickness is not well constrained. Here, we present a two-step mass-conservation approach for mapping ice thickness. Measurements are naturally reproduced. The reliability is readily assessible from a complementary map of error estimates.
Andreas Kääb, Bas Altena, and Joseph Mascaro
Nat. Hazards Earth Syst. Sci., 17, 627–639, https://doi.org/10.5194/nhess-17-627-2017, https://doi.org/10.5194/nhess-17-627-2017, 2017
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We evaluate for the first time a new class of optical satellite images for measuring Earth surface displacements due to earthquakes – images from cubesats. The PlanetScope cubesats used in this study are 10 cm × 10 cm × 30 cm small and standardized satellites. Around 120 of these cubesats orbit around Earth and are about to provide daily 2–4 m resolution images of the entire land surface of the Earth.
Luc Girod, Christopher Nuth, Andreas Kääb, Bernd Etzelmüller, and Jack Kohler
The Cryosphere, 11, 827–840, https://doi.org/10.5194/tc-11-827-2017, https://doi.org/10.5194/tc-11-827-2017, 2017
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While gathering data on a changing environment is often a costly and complicated endeavour, it is also the backbone of all research. What if one could measure elevation change by just strapping a camera and a hiking GPS under an helicopter or a small airplane used for transportation and gather data on the ground bellow the flight path? In this article, we present a way to do exactly that and show an example survey where it helped compute the volume of ice lost by a glacier in Svalbard.
Tazio Strozzi, Andreas Kääb, and Thomas Schellenberger
The Cryosphere, 11, 553–566, https://doi.org/10.5194/tc-11-553-2017, https://doi.org/10.5194/tc-11-553-2017, 2017
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The strong atmospheric warming observed since the 1990s in polar regions requires quantifying the contribution to sea level rise of glaciers and ice caps, but for large areas we do not have much information on ice dynamic fluctuations. The recent increase in satellite data opens up new possibilities to monitor ice flow. We observed over Stonebreen on Edgeøya (Svalbard) a strong increase since 2012 in ice surface velocity along with a decrease in volume and an advance in frontal extension.
Thomas Schellenberger, Thorben Dunse, Andreas Kääb, Thomas Vikhamar Schuler, Jon Ove Hagen, and Carleen H. Reijmer
The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-5, https://doi.org/10.5194/tc-2017-5, 2017
Preprint withdrawn
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Basin-3, NE-Svalbard, was still surging with 10 m d-1 in July 2016. After a speed peak of 18.8 m d-1 in Dec 2012/Jan 2013, speed-ups are overlying the fast flow every summer. The glacier is massively calving icebergs (5.2 Gt yr-1 ~ 2 L drinking water for every human being daily!) which in the same order of magnitude as all other Svalbard glaciers together.
Since autumn 2015 also Basin-2 is surging with maximum velocities of 8.7 m d-1, an advance of more than 2 km and a mass loss of 0.7 Gt yr-1.
Désirée Treichler and Andreas Kääb
The Cryosphere, 10, 2129–2146, https://doi.org/10.5194/tc-10-2129-2016, https://doi.org/10.5194/tc-10-2129-2016, 2016
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Satellite data are often the only source of information on mountain glaciers. We show that data from ICESat laser satellite can accurately reflect glacier volume development in 2003–2008, also for individual years. We detect a spatially varying elevation bias in commonly used data sets, and provide a correction that strongly increases the significance of the glacier change estimates – a crucial driver of climate-induced meltwater changes that directly affect the life of lowland populations.
Luc Girod, Christopher Nuth, and Andreas Kääb
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLI-B8, 489–494, https://doi.org/10.5194/isprs-archives-XLI-B8-489-2016, https://doi.org/10.5194/isprs-archives-XLI-B8-489-2016, 2016
T. Schellenberger, T. Dunse, A. Kääb, J. Kohler, and C. H. Reijmer
The Cryosphere, 9, 2339–2355, https://doi.org/10.5194/tc-9-2339-2015, https://doi.org/10.5194/tc-9-2339-2015, 2015
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Kronebreen and Kongsbreen are among the fastest flowing glaciers on Svalbard, and surface speeds reached up to 3.2m d-1 at Kronebreen in summer 2013 and 2.7m d-1 at Kongsbreen in late autumn 2012 as retrieved from SAR satellite data. Both glaciers retreated significantly during the observation period, Kongsbreen up to 1800m or 2.5km2 and Kronebreen up to 850m or 2.8km2. Both glaciers are important contributors to the total dynamic mass loss from the Svalbard archipelago.
A. Kääb, D. Treichler, C. Nuth, and E. Berthier
The Cryosphere, 9, 557–564, https://doi.org/10.5194/tc-9-557-2015, https://doi.org/10.5194/tc-9-557-2015, 2015
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Based on satellite laser altimetry over the Pamir--Karakoram Himalaya we detect strongest elevation losses over east Nyainqentanglha Shan and Spiti--Lahaul but slight elevation gains over west Kunlun Shan rather than over Karakoram. The current sea-level contribution of Pamir--Karakoram Himalaya glaciers is about 10% of the total global contribution of glaciers outside the ice sheets. We also improve estimates of glacier imbalance contribution to river discharge in the Himalayas.
T. Dunse, T. Schellenberger, J. O. Hagen, A. Kääb, T. V. Schuler, and C. H. Reijmer
The Cryosphere, 9, 197–215, https://doi.org/10.5194/tc-9-197-2015, https://doi.org/10.5194/tc-9-197-2015, 2015
A. Kääb, L. Girod, and I. Berthling
The Cryosphere, 8, 1041–1056, https://doi.org/10.5194/tc-8-1041-2014, https://doi.org/10.5194/tc-8-1041-2014, 2014
A. Kääb, M. Lamare, and M. Abrams
Hydrol. Earth Syst. Sci., 17, 4671–4683, https://doi.org/10.5194/hess-17-4671-2013, https://doi.org/10.5194/hess-17-4671-2013, 2013
C. Nuth, J. Kohler, M. König, A. von Deschwanden, J. O. Hagen, A. Kääb, G. Moholdt, and R. Pettersson
The Cryosphere, 7, 1603–1621, https://doi.org/10.5194/tc-7-1603-2013, https://doi.org/10.5194/tc-7-1603-2013, 2013
J. Gardelle, E. Berthier, Y. Arnaud, and A. Kääb
The Cryosphere, 7, 1263–1286, https://doi.org/10.5194/tc-7-1263-2013, https://doi.org/10.5194/tc-7-1263-2013, 2013
M. Zemp, E. Thibert, M. Huss, D. Stumm, C. Rolstad Denby, C. Nuth, S. U. Nussbaumer, G. Moholdt, A. Mercer, C. Mayer, P. C. Joerg, P. Jansson, B. Hynek, A. Fischer, H. Escher-Vetter, H. Elvehøy, and L. M. Andreassen
The Cryosphere, 7, 1227–1245, https://doi.org/10.5194/tc-7-1227-2013, https://doi.org/10.5194/tc-7-1227-2013, 2013
Related subject area
Image processing
Auroral alert version 1.0: two-step automatic detection of sudden aurora intensification from all-sky JPEG images
Automatic detection of calving events from time-lapse imagery at Tunabreen, Svalbard
Integration of remote sensing and geographic information systems for geological fault detection on the island of Crete, Greece
Consideration of NDVI thematic changes in density analysis and floristic composition of Wadi Yalamlam, Saudi Arabia
A comparative study of auroral morphology distribution between the Northern and Southern Hemisphere based on automatic classification
Understanding of morphometric features for adequate water resource management in arid environments
Soil salinity mapping and hydrological drought indices assessment in arid environments based on remote sensing techniques
Realization of daily evapotranspiration in arid ecosystems based on remote sensing techniques
Digital photography for assessing the link between vegetation phenology and CO2 exchange in two contrasting northern ecosystems
Automatic georeferencing of astronaut auroral photography
Image georectification and feature tracking toolbox: ImGRAFT
Masatoshi Yamauchi and Urban Brändström
Geosci. Instrum. Method. Data Syst., 12, 71–90, https://doi.org/10.5194/gi-12-71-2023, https://doi.org/10.5194/gi-12-71-2023, 2023
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Potential users of all-sky aurora images even include power companies, tourists, and aurora enthusiasts. However, these potential users are normally not familiar with interpreting these images. To make them comprehensive for more users, we developed an automatic evaluation system of auroral activity level. The method involves two steps: first making a simple set of numbers that describes the auroral activity and then further simplifying them into several levels (Level 6 is an auroral explosion).
Dorothée Vallot, Sigit Adinugroho, Robin Strand, Penelope How, Rickard Pettersson, Douglas I. Benn, and Nicholas R. J. Hulton
Geosci. Instrum. Method. Data Syst., 8, 113–127, https://doi.org/10.5194/gi-8-113-2019, https://doi.org/10.5194/gi-8-113-2019, 2019
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This paper presents a novel method to quantify the sizes and frequency of calving events from time-lapse camera images. The calving front of a tidewater glacier experiences different episodes of iceberg deliveries that can be captured by a time-lapse camera situated in front of the glacier. An automatic way of detecting calving events is presented here and compared to manually detected events.
Mohamed Elhag and Dalal Alshamsi
Geosci. Instrum. Method. Data Syst., 8, 45–54, https://doi.org/10.5194/gi-8-45-2019, https://doi.org/10.5194/gi-8-45-2019, 2019
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The article deals with the designation of fault detection on the island of Crete. The delineation is based on the integration method of remote sensing and GIS. The crucial finding is how to differentiate between faults and water streams. The results showed a robust approach to fault detection.
Amal Y. Aldhebiani, Mohamed Elhag, Ahmad K. Hegazy, Hanaa K. Galal, and Norah S. Mufareh
Geosci. Instrum. Method. Data Syst., 7, 297–306, https://doi.org/10.5194/gi-7-297-2018, https://doi.org/10.5194/gi-7-297-2018, 2018
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The current article focuses on plant diversity assessment in arid environments. Species richness and species evenness equations were used to meet the objectives. Remote sensing techniques were used to detect normalized difference vegetation index (NDVI) temporal changes. Two datasets were used to realize the NDVI, and post-chance detection (PCC) techniques were used to evaluate plant diversity status over a period of 4 years. The results show a recognizable loss in plant biodiversity.
Qiuju Yang and Ze-Jun Hu
Geosci. Instrum. Method. Data Syst., 7, 113–122, https://doi.org/10.5194/gi-7-113-2018, https://doi.org/10.5194/gi-7-113-2018, 2018
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Based on the morphological characteristics of the four dayside auroral types on images at the Chinese Arctic Yellow River Station (YRS), and by extracting the local binary pattern features and using k-nearest classifier, we make an automatic classification to the auroral images of the YRS and the South Pole Station and obtain the occurrence distribution of the dayside aurora morphology. The results indicate that these auroral types present similar occurrence distributions in the two stations.
Mohamed Elhag, Hanaa K. Galal, and Haneen Alsubaie
Geosci. Instrum. Method. Data Syst., 6, 293–300, https://doi.org/10.5194/gi-6-293-2017, https://doi.org/10.5194/gi-6-293-2017, 2017
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This article focus on morphometric features and their role in water resource management at the basin scale. The estimation of the features requires an adequate understanding of DEM feature extractions. The findings of the current study will help decision makers to improve the adopted water resource management strategies in similar geographic locations.
Mohamed Elhag and Jarbou A. Bahrawi
Geosci. Instrum. Method. Data Syst., 6, 149–158, https://doi.org/10.5194/gi-6-149-2017, https://doi.org/10.5194/gi-6-149-2017, 2017
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The current work is aimed at the quantification of the hydrological drought indices' response to soil salinity. Work has been done to overcome the problems of soil salinity on a large scale for better water resource management, especially in arid environments.
Mohamed Elhag and Jarbou A. Bahrawi
Geosci. Instrum. Method. Data Syst., 6, 141–147, https://doi.org/10.5194/gi-6-141-2017, https://doi.org/10.5194/gi-6-141-2017, 2017
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Work has been done to overcome the problems of evapotranspiration on a large scale for better water resources management, especially in arid environments.
Maiju Linkosalmi, Mika Aurela, Juha-Pekka Tuovinen, Mikko Peltoniemi, Cemal M. Tanis, Ali N. Arslan, Pasi Kolari, Kristin Böttcher, Tuula Aalto, Juuso Rainne, Juha Hatakka, and Tuomas Laurila
Geosci. Instrum. Method. Data Syst., 5, 417–426, https://doi.org/10.5194/gi-5-417-2016, https://doi.org/10.5194/gi-5-417-2016, 2016
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Digital photography has become a widely used tool for monitoring the vegetation phenology. The seasonal cycle of the greenness index obtained from photographs correlated well with the CO2 exchange of the plants at our wetland and Scots pine forest sites. While the seasonal changes in the greenness were more obvious for the ecosystem dominated by annual plants, clear seasonal patterns were also observed for the evergreen forest.
Maik Riechert, Andrew P. Walsh, Alexander Gerst, and Matthew G. G. T. Taylor
Geosci. Instrum. Method. Data Syst., 5, 289–304, https://doi.org/10.5194/gi-5-289-2016, https://doi.org/10.5194/gi-5-289-2016, 2016
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Astronauts on board the International Space Station have taken thousands of high-quality images of the northern and southern lights (aurorae). Because the images were not taken as part of a specific research project, no information about exactly where the camera was pointing was available. We have used the stars in the images to reconstruct this information. Now we can tell the latitudes and longitudes of the aurorae in the images and use them for research. The data are publicly available.
A. Messerli and A. Grinsted
Geosci. Instrum. Method. Data Syst., 4, 23–34, https://doi.org/10.5194/gi-4-23-2015, https://doi.org/10.5194/gi-4-23-2015, 2015
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The use of time-lapse cameras is becoming an ever more popular method of observing changes in the natural environment. This study provides an overview of the newly developed Image GeoRectification And Feature Tracking toolbox (ImGRAFT). The paper outlines the main function of the toolbox and describes each of the key processes needed to transform a pair of terrestrial time-lapse images into a velocity field. The tool is presented using a case study of glacier surface motion at Engabreen, Norway.
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Short summary
Historical surveys performed through the use of aerial photography gave us the first maps of the Arctic. Nearly a century later, a renewed interest in studying the Arctic is rising from the need to understand and quantify climate change. It is therefore time to dig up the archives and extract the maximum of information from the images using the most modern methods. In this study, we show that the aerial survey of Svalbard in 1936–38 provides us with valuable data on the archipelago's glaciers.
Historical surveys performed through the use of aerial photography gave us the first maps of the...
