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4. Annual mass budget of Antarctic ice shelves, 1997-2021 (WP3 EO Workshop)

Author

Davison, Benjamin, Hogg, Anna, Gourmelen, Noel, Jakob, Livia, Wuite, Jan, Nagler, Thomas, Greene, Chad, Andreasen, Julia, and Engdahl, Marcus

Abstract

This presentation was held at the OCEAN:ICE This presentation was held at the OCEAN:ICE WP3 EO Workshop exploring Antarctic fluxes in observations and climate and ice sheet models. The workshop took place in Copenhagen, Denmark from the 23rd to 24th of May in 2023. Benjamin Davison delivered thispresentation on May 23rd, 2023 during Session 1 of the workshop, Antarctic surface datasets from in-situ and Earth Observations. &nbsp

Published
2023
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5. Mass balance of the Greenland and Antarctic ice sheets from 1992 to 2020

Author

Otosaka, Inès N., primary, Shepherd, Andrew, additional, Ivins, Erik R., additional, Schlegel, Nicole-Jeanne, additional, Amory, Charles, additional, van den Broeke, Michiel R., additional, Horwath, Martin, additional, Joughin, Ian, additional, King, Michalea D., additional, Krinner, Gerhard, additional, Nowicki, Sophie, additional, Payne, Anthony J., additional, Rignot, Eric, additional, Scambos, Ted, additional, Simon, Karen M., additional, Smith, Benjamin E., additional, Sørensen, Louise S., additional, Velicogna, Isabella, additional, Whitehouse, Pippa L., additional, A, Geruo, additional, Agosta, Cécile, additional, Ahlstrøm, Andreas P., additional, Blazquez, Alejandro, additional, Colgan, William, additional, Engdahl, Marcus E., additional, Fettweis, Xavier, additional, Forsberg, Rene, additional, Gallée, Hubert, additional, Gardner, Alex, additional, Gilbert, Lin, additional, Gourmelen, Noel, additional, Groh, Andreas, additional, Gunter, Brian C., additional, Harig, Christopher, additional, Helm, Veit, additional, Khan, Shfaqat Abbas, additional, Kittel, Christoph, additional, Konrad, Hannes, additional, Langen, Peter L., additional, Lecavalier, Benoit S., additional, Liang, Chia-Chun, additional, Loomis, Bryant D., additional, McMillan, Malcolm, additional, Melini, Daniele, additional, Mernild, Sebastian H., additional, Mottram, Ruth, additional, Mouginot, Jeremie, additional, Nilsson, Johan, additional, Noël, Brice, additional, Pattle, Mark E., additional, Peltier, William R., additional, Pie, Nadege, additional, Roca, Mònica, additional, Sasgen, Ingo, additional, Save, Himanshu V., additional, Seo, Ki-Weon, additional, Scheuchl, Bernd, additional, Schrama, Ernst J. O., additional, Schröder, Ludwig, additional, Simonsen, Sebastian B., additional, Slater, Thomas, additional, Spada, Giorgio, additional, Sutterley, Tyler C., additional, Vishwakarma, Bramha Dutt, additional, van Wessem, Jan Melchior, additional, Wiese, David, additional, van der Wal, Wouter, additional, and Wouters, Bert, additional

Published
2023
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6. Mass balance of the Greenland and Antarctic ice sheets from 1992 to 2020

Author

Otosaka, Inès N., Shepherd, Andrew, Ivins, Erik R., Schlegel, Nicole Jeanne, Amory, Charles, Van Den Broeke, Michiel R., Horwath, Martin, Joughin, Ian, King, Michalea D., Krinner, Gerhard, Nowicki, Sophie, Payne, Anthony J., Rignot, Eric, Scambos, Ted, Simon, Karen M., Smith, Benjamin E., Sørensen, Louise S., Velicogna, Isabella, Whitehouse, Pippa L., Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas P., Blazquez, Alejandro, Colgan, William, Engdahl, Marcus E., Fettweis, Xavier, Forsberg, Rene, Gallée, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian C., Harig, Christopher, Helm, Veit, Khan, Shfaqat Abbas, Kittel, Christoph, Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit S., Liang, Chia Chun, Loomis, Bryant D., McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian H., Mottram, Ruth, Mouginot, Jeremie, Nilsson, Johan, Noël, Brice, Pattle, Mark E., Peltier, William R., Pie, Nadege, Roca, Mònica, Sasgen, Ingo, Save, Himanshu V., Seo, Ki Weon, Scheuchl, Bernd, Schrama, Ernst J.O., Schröder, Ludwig, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler C., Vishwakarma, Bramha Dutt, Van Wessem, Jan Melchior, Wiese, David, Van Der Wal, Wouter, Wouters, Bert, Otosaka, Inès N., Shepherd, Andrew, Ivins, Erik R., Schlegel, Nicole Jeanne, Amory, Charles, Van Den Broeke, Michiel R., Horwath, Martin, Joughin, Ian, King, Michalea D., Krinner, Gerhard, Nowicki, Sophie, Payne, Anthony J., Rignot, Eric, Scambos, Ted, Simon, Karen M., Smith, Benjamin E., Sørensen, Louise S., Velicogna, Isabella, Whitehouse, Pippa L., Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas P., Blazquez, Alejandro, Colgan, William, Engdahl, Marcus E., Fettweis, Xavier, Forsberg, Rene, Gallée, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian C., Harig, Christopher, Helm, Veit, Khan, Shfaqat Abbas, Kittel, Christoph, Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit S., Liang, Chia Chun, Loomis, Bryant D., McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian H., Mottram, Ruth, Mouginot, Jeremie, Nilsson, Johan, Noël, Brice, Pattle, Mark E., Peltier, William R., Pie, Nadege, Roca, Mònica, Sasgen, Ingo, Save, Himanshu V., Seo, Ki Weon, Scheuchl, Bernd, Schrama, Ernst J.O., Schröder, Ludwig, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler C., Vishwakarma, Bramha Dutt, Van Wessem, Jan Melchior, Wiese, David, Van Der Wal, Wouter, and Wouters, Bert

Abstract

Ice losses from the Greenland and Antarctic ice sheets have accelerated since the 1990s, accounting for a significant increase in the global mean sea level. Here, we present a new 29-year record of ice sheet mass balance from 1992 to 2020 from the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE). We compare and combine 50 independent estimates of ice sheet mass balance derived from satellite observations of temporal changes in ice sheet flow, in ice sheet volume, and in Earth's gravity field. Between 1992 and 2020, the ice sheets contributed 21.0±1.9 mm to global mean sea level, with the rate of mass loss rising from 105 Gt yr−1 between 1992 and 1996 to 372 Gt yr−1 between 2016 and 2020. In Greenland, the rate of mass loss is 169±9 Gt yr−1 between 1992 and 2020, but there are large inter-annual variations in mass balance, with mass loss ranging from 86 Gt yr−1 in 2017 to 444 Gt yr−1 in 2019 due to large variability in surface mass balance. In Antarctica, ice losses continue to be dominated by mass loss from West Antarctica (82±9 Gt yr−1) and, to a lesser extent, from the Antarctic Peninsula (13±5 Gt yr−1). East Antarctica remains close to a state of balance, with a small gain of 3±15 Gt yr−1, but is the most uncertain component of Antarctica's mass balance. The dataset is publicly available at https://doi.org/10.5285/77B64C55-7166-4A06-9DEF-2E400398E452 (IMBIE Team, 2021).

Published
2023

7. Mass balance of the Greenland and Antarctic ice sheets from 1992 to 2020

Author

Sub Dynamics Meteorology, Structural geology and EM, Marine and Atmospheric Research, Otosaka, Inès N., Shepherd, Andrew, Ivins, Erik R., Schlegel, Nicole Jeanne, Amory, Charles, Van Den Broeke, Michiel R., Horwath, Martin, Joughin, Ian, King, Michalea D., Krinner, Gerhard, Nowicki, Sophie, Payne, Anthony J., Rignot, Eric, Scambos, Ted, Simon, Karen M., Smith, Benjamin E., Sørensen, Louise S., Velicogna, Isabella, Whitehouse, Pippa L., Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas P., Blazquez, Alejandro, Colgan, William, Engdahl, Marcus E., Fettweis, Xavier, Forsberg, Rene, Gallée, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian C., Harig, Christopher, Helm, Veit, Khan, Shfaqat Abbas, Kittel, Christoph, Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit S., Liang, Chia Chun, Loomis, Bryant D., McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian H., Mottram, Ruth, Mouginot, Jeremie, Nilsson, Johan, Noël, Brice, Pattle, Mark E., Peltier, William R., Pie, Nadege, Roca, Mònica, Sasgen, Ingo, Save, Himanshu V., Seo, Ki Weon, Scheuchl, Bernd, Schrama, Ernst J.O., Schröder, Ludwig, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler C., Vishwakarma, Bramha Dutt, Van Wessem, Jan Melchior, Wiese, David, Van Der Wal, Wouter, Wouters, Bert, Sub Dynamics Meteorology, Structural geology and EM, Marine and Atmospheric Research, Otosaka, Inès N., Shepherd, Andrew, Ivins, Erik R., Schlegel, Nicole Jeanne, Amory, Charles, Van Den Broeke, Michiel R., Horwath, Martin, Joughin, Ian, King, Michalea D., Krinner, Gerhard, Nowicki, Sophie, Payne, Anthony J., Rignot, Eric, Scambos, Ted, Simon, Karen M., Smith, Benjamin E., Sørensen, Louise S., Velicogna, Isabella, Whitehouse, Pippa L., Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas P., Blazquez, Alejandro, Colgan, William, Engdahl, Marcus E., Fettweis, Xavier, Forsberg, Rene, Gallée, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian C., Harig, Christopher, Helm, Veit, Khan, Shfaqat Abbas, Kittel, Christoph, Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit S., Liang, Chia Chun, Loomis, Bryant D., McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian H., Mottram, Ruth, Mouginot, Jeremie, Nilsson, Johan, Noël, Brice, Pattle, Mark E., Peltier, William R., Pie, Nadege, Roca, Mònica, Sasgen, Ingo, Save, Himanshu V., Seo, Ki Weon, Scheuchl, Bernd, Schrama, Ernst J.O., Schröder, Ludwig, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler C., Vishwakarma, Bramha Dutt, Van Wessem, Jan Melchior, Wiese, David, Van Der Wal, Wouter, and Wouters, Bert

Published
2023

9. Mass Balance of the Greenland and Antarctic Ice Sheets from 1992 to 2020

Author

Otosaka, Inès N., primary, Shepherd, Andrew, additional, Ivins, Erik R., additional, Schlegel, Nicole-Jeanne, additional, Amory, Charles, additional, van den Broeke, Michiel, additional, Horwath, Martin, additional, Joughin, Ian, additional, King, Michalea, additional, Krinner, Gerhard, additional, Nowicki, Sophie, additional, Payne, Tony, additional, Rignot, Eric, additional, Scambos, Ted, additional, Simon, Karen M., additional, Smith, Benjamin, additional, Sandberg Sørensen, Louise, additional, Velicogna, Isabella, additional, Whitehouse, Pippa, additional, A, Geruo, additional, Agosta, Cécile, additional, Ahlstrøm, Andreas P., additional, Blazquez, Alejandro, additional, Colgan, William, additional, Engdahl, Marcus, additional, Fettweis, Xavier, additional, Forsberg, Rene, additional, Gallée, Hubert, additional, Gardner, Alex, additional, Gilbert, Lin, additional, Gourmelen, Noel, additional, Groh, Andreas, additional, Gunter, Brian C., additional, Harig, Christopher, additional, Helm, Veit, additional, Khan, Shfaqat Abbas, additional, Konrad, Hannes, additional, Langen, Peter, additional, Lecavalier, Benoit, additional, Liang, Chia-Chun, additional, Loomis, Bryant, additional, McMillan, Malcolm, additional, Melini, Daniele, additional, Mernild, Sebastian H., additional, Mottram, Ruth, additional, Mouginot, Jeremie, additional, Nilsson, Johan, additional, Noël, Brice, additional, Pattle, Mark E., additional, Peltier, William R., additional, Pie, Nadege, additional, Sasgen, Ingo, additional, Save, Himanshu, additional, Seo, Ki-Weon, additional, Scheuchl, Bernd, additional, Schrama, Ernst, additional, Schröder, Ludwig, additional, Simonsen, Sebastian B., additional, Slater, Thomas, additional, Spada, Giorgio, additional, Sutterley, Tyler, additional, Vishwakarma, Bramha Dutt, additional, van Wessem, Jan Melchior, additional, Wiese, David, additional, van der Wal, Wouter, additional, and Wouters, Bert, additional

Published
2022
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10. Skolkuratorns perspektiv på elevhälsoarbete : Med fokus på det främjande och förebyggande arbetet

Author

Engdahl, Marcus, Olofsson, Simone, Engdahl, Marcus, and Olofsson, Simone

Abstract

Skolkuratorns unika roll i skolan bidrar med ett psykosocialt perspektiv i syfte att främja elevernas välbefinnande och utveckling. Hur elevhälsoarbetet utformas kan dock se olika ut beroende på skolans behov och förutsättningar. Studiens syfte är att undersöka skolkuratorns upplevelse av hur elevhälsoarbetet med fokus på det främjande och förebyggande arbetet bedrivs och organiseras för eleverna i grundskolan. Författarna har utfört en kvalitativ studie genom fem semi-strukturerade intervjuer med skolkuratorer. Utifrån intervjumaterialet har en tematisk analys genomförts. De viktigaste slutsatserna innefattar bland annat att det främjande och förebyggande arbetet är prioriterat samtidigt som det akutstyrda arbetet tar mycket tid och resurser. En annan slutsats som nås är att samverkan har en stor betydelse för ett gott elevhälsoarbete. Utöver dessa slutsatser framkommer även ett flertal komplexa utmaningar som präglas av resurs- och ekonomibrist samt en brist på tidseffektivitet. Utifrån studiens resultat anser författarna att ytterligare forskning angående implementering av evidensbaserade metoder bör genomföras. Detta då skolkuratorer ofta inser vikten av dessa metoder men lyfter samtidigt fram att de inte alltid är tillräckligt anpassade till skolmiljön., The school counselor's unique role in school contributes with a psychosocial perspective to promote pupils' well-being and development. However, how pupil health work is designed may differ depending on the school's needs and conditions. The aim of the study is to investigate the school counselor's experience of how pupil health work, with a focus on the promotive and preventive work, is conducted and organized for the students in elementary school. The study uses a qualitative method and the authors organized five semi-structured interviews with school counselors. The main conclusions include, among other things, that promotion and prevention are a priority, while emergency-controlled work takes a lot of time and resources. Another conclusion is that collaboration is of great importance for good pupil health work. In addition to these conclusions, several complex challenges are also emerging, characterized by resource and economic deficiencies and a lack of time efficiency. Based on the results of the study, the authors believe that further research on the implementation of evidence-based methods should be conducted. This is because school counselors often realize the importance of these methods but at the same time highlight that they are not always sufficiently adapted to the school environment.

Published
2022

11. Sentinel-1 interferometric coherence as a vegetation index for agriculture

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Villarroya-Carpio, Arturo, Lopez-Sanchez, Juan M., Engdahl, Marcus E., Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Villarroya-Carpio, Arturo, Lopez-Sanchez, Juan M., and Engdahl, Marcus E.

Abstract

In this study, the use of Sentinel-1 interferometric coherence data as a tool for crop monitoring has been explored. For this purpose, time series of images acquired by Sentinel-1 and 2 spanning 2017 have been analysed. The study site is an agricultural area in Sevilla, Spain, where 16 different crop species were cultivated during that year. The time series of 6-day repeat-pass coherence measured at each polarimetric channel (VV and VH), as well as their difference, have been compared to the NDVI and to the backscattering ratio (VH/VV) and other indices based on backscatter. The contribution of different decorrelation sources and the effect of the bias from the space-averaged sample coherence magnitude estimation have been evaluated. Likewise, the usage of 12 days as temporal baseline was tested. The study has been carried for three different orbits, characterised by different incidence angles and acquisition times. All results support using coherence as a measure for monitoring the crop growing season, as it shows good correlations with the NDVI (R2>0.7), and its temporal evolution fits well the main phenological stages of the crops. Although each crop shows its own evolution, the performance of coherence as a vegetation index is high for most of them. VV is generally more correlated with the NDVI than VH. For crop types characterised by low plant density, this difference decreases, with VH even showing higher correlation values in some cases. For a few crop types, such as rice, the backscattering ratio outperforms the coherence in following the growth stages of the plants. Since both coherence and backscattering are directly computed from the radar images, they could be used as complementary sources of information for this purpose. Notably, the measured coherence performs well without the need of compensating the thermal noise decorrelation or the bias due to the finite equivalent number of looks.

Published
2022

12. Mass balance of the Greenland Ice Sheet from 1992 to 2018

Author

Shepherd, Andrew, Ivins, Erik, Rignot, Eric, Smith, Ben, van den Broeke, Michiel, Velicogna, Isabella, Whitehouse, Pippa, Briggs, Kate, Joughin, Ian, Krinner, Gerhard, Nowicki, Sophie, Payne, Tony, Scambos, Ted, Schlegel, Nicole, Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas, Babonis, Greg, Barletta, Valentina R., Bjørk, Anders A., Blazquez, Alejandro, Bonin, Jennifer, Colgan, William, Csatho, Beata, Cullather, Richard, Engdahl, Marcus E., Felikson, Denis, Fettweis, Xavier, Forsberg, Rene, Hogg, Anna E., Gallee, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian, Hanna, Edward, Harig, Christopher, Helm, Veit, Horvath, Alexander, Horwath, Martin, Khan, Shfaqat, Kjeldsen, Kristian K., Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit, Loomis, Bryant, Luthcke, Scott, McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian, Mohajerani, Yara, Moore, Philip, Mottram, Ruth, Mouginot, Jeremie, Moyano, Gorka, Muir, Alan, Nagler, Thomas, Nield, Grace, Nilsson, Johan, Noël, Brice, Otosaka, Ines, Pattle, Mark E., Peltier, W. Richard, Pie, Nadège, Rietbroek, Roelof, Rott, Helmut, Sørensen, Louise Sandberg, Sasgen, Ingo, Save, Himanshu, Scheuchl, Bernd, Schrama, Ernst, Schröder, Ludwig, Seo, Ki-Weon, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler, Talpe, Matthieu, Tarasov, Lev, Jan van de Berg, Willem, van der Wal, Wouter, van Wessem, Melchior, Vishwakarma, Bramha Dutt, Wiese, David, Wilton, David, Wagner, Thomas, Wouters, Bert, Wuite, Jan, Team, The IMBIE, Marine and Atmospheric Research, Sub Dynamics Meteorology, Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Andrew Shepherd, Erik Ivin, Eric Rignot, Ben Smith, Michiel van den Broeke, Isabella Velicogna, Pippa Whitehouse, Kate Brigg, Ian Joughin, Gerhard Krinner, Sophie Nowicki, Tony Payne, Ted Scambo, Nicole Schlegel, A Geruo, Cécile Agosta, Andreas Ahlstrøm, Greg Baboni, Valentina R. Barletta, Anders A. Bjørk, Alejandro Blazquez, Jennifer Bonin, William Colgan, Beata Csatho, Richard Cullather, Marcus E. Engdahl, Denis Felikson, Xavier Fettwei, Rene Forsberg, Anna E. Hogg, Hubert Gallee, Alex Gardner, Lin Gilbert, Noel Gourmelen, Andreas Groh, Brian Gunter, Edward Hanna, Christopher Harig, Veit Helm, Alexander Horvath, Martin Horwath, Shfaqat Khan, Kristian K. Kjeldsen, Hannes Konrad, Peter L. Langen, Benoit Lecavalier, Bryant Loomi, Scott Luthcke, Malcolm McMillan, Daniele Melini, Sebastian Mernild, Yara Mohajerani, Philip Moore, Ruth Mottram, Jeremie Mouginot, Gorka Moyano, Alan Muir, Thomas Nagler, Grace Nield, Johan Nilsson, Brice Noël, Ines Otosaka, Mark E. Pattle, W. Richard Peltier, Nadège Pie, Roelof Rietbroek, Helmut Rott, Louise Sandberg Sørensen, Ingo Sasgen, Himanshu Save, Bernd Scheuchl, Ernst Schrama, Ludwig Schröder, Ki-Weon Seo, Sebastian B. Simonsen, Thomas Slater, Giorgio Spada, Tyler Sutterley, Matthieu Talpe, Lev Tarasov, Willem Jan van de Berg, Wouter van der Wal, Melchior van Wessem, Bramha Dutt Vishwakarma, David Wiese, David Wilton, Thomas Wagner, Bert Wouter, Jan Wuite, Marine and Atmospheric Research, and Sub Dynamics Meteorology

Subjects
geography, Multidisciplinary, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Global warming, Greenland ice sheet, Climate change, Glacier, GLACIAL ISOSTATIC-ADJUSTMENT, RELATIVE SEA-LEVEL PETERMANN GLACIER, ELEVATION CHANGE, SURFACE, GRACE, CLIMATE, MODEL, ACCELERATION, ANTARCTICA, 010502 geochemistry & geophysics, Atmospheric sciences, 01 natural sciences, Glacier mass balance, 13. Climate action, Taverne, [SDE]Environmental Sciences, SDG 13 - Climate Action, Environmental science, Climate model, Ice sheet, F840 Physical Geography, Meltwater, 0105 earth and related environmental sciences
Abstract

ArticlePublished: 10 December 2019This is an unedited manuscript that has been accepted for publication. Nature Research are providing this early version of the manuscript as a service to our customers. The manuscript will undergo copyediting, typesetting and a proof review before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers apply.Mass balance of the Greenland Ice Sheet from 1992 to 2018The IMBIE TeamNature (2019)Cite this article6914 Accesses1410 AltmetricMetricsdetailsAbstractIn recent decades, the Greenland Ice Sheet has been a major contributor to global sea-level rise1,2, and it is expected to be so in the future3. Although increases in glacier flow4–6 and surface melting7–9 have been driven by oceanic10–12 and atmospheric13,14 warming, the degree and trajectory of today’s imbalance remain uncertain. Here we compare and combine 26 individual satellite measurements of changes in the ice sheet’s volume, flow and gravitational potential to produce a reconciled estimate of its mass balance. Although the ice sheet was close to a state of balance in the 1990s, annual losses have risen since then, peaking at 335 ± 62 billion tonnes per year in 2011. In all, Greenland lost 3,800 ± 339 billion tonnes of ice between 1992 and 2018, causing the mean sea level to rise by 10.6 ± 0.9 millimetres. Using three regional climate models, we show that reduced surface mass balance has driven 1,971 ± 555 billion tonnes (52%) of the ice loss owing to increased meltwater runoff. The remaining 1,827 ± 538 billion tonnes (48%) of ice loss was due to increased glacier discharge, which rose from 41 ± 37 billion tonnes per year in the 1990s to 87 ± 25 billion tonnes per year since then. Between 2013 and 2017, the total rate of ice loss slowed to 217 ± 32 billion tonnes per year, on average, as atmospheric circulation favoured cooler conditions15 and as ocean temperatures fell at the terminus of Jakobshavn Isbræ16. Cumulative ice losses from Greenland as a whole have been close to the IPCC’s predicted rates for their high-end climate warming scenario17, which forecast an additional 50 to 120 millimetres of global sea-level rise by 2100 when compared to their central estimate.

Published
2020

13. Sentinel-1 InSAR Coherence for Land Cover Mapping : A Comparison of Multiple Feature-Based Classifiers

Author

Jacob, Alexander W., Vicente-Guijalba, Fernando, Lopez-Martinez, Carlos, Lopez-Sanchez, Juan M., Litzinger, Marius, Kristen, Harald, Mestre-Quereda, Alejandro, Ziolkowski, Dariusz, Lavalle, Marco, Notarnicola, Claudia, Suresh, Gopika, Antropov, Oleg, Ge, Shaojia, Praks, Jaan, Ban, Yifang, Pottier, Eric, Franquet, Jordi Joan Mallorqui, Duro, Javier, Engdahl, Marcus E., Jacob, Alexander W., Vicente-Guijalba, Fernando, Lopez-Martinez, Carlos, Lopez-Sanchez, Juan M., Litzinger, Marius, Kristen, Harald, Mestre-Quereda, Alejandro, Ziolkowski, Dariusz, Lavalle, Marco, Notarnicola, Claudia, Suresh, Gopika, Antropov, Oleg, Ge, Shaojia, Praks, Jaan, Ban, Yifang, Pottier, Eric, Franquet, Jordi Joan Mallorqui, Duro, Javier, and Engdahl, Marcus E.

Abstract

This article investigates and demonstrates the suitability of the Sentinel-1 interferometric coherence for land cover and vegetation mapping. In addition, this study analyzes the performance of this feature along with polarization and intensity products according to different classification strategies and algorithms. Seven different classification workflows were evaluated, covering pixel- and object-based analyses, unsupervised and supervised classification, different machine-learning classifiers, and the various effects of distinct input features in the SAR domain-interferometric coherence, backscattered intensities, and polarization. All classifications followed the Corine land cover nomenclature. Three different study areas in Europe were selected during 2015 and 2016 campaigns to maximize diversity of land cover. Overall accuracies (OA), ranging from 70% to 90%, were achieved depending on the study area and methodology, considering between 9 and 15 classes. The best results were achieved in the rather flat area of Donana wetlands National Park in Spain (OA 90%), but even the challenging alpine terrain around the city of Merano in northern Italy (OA 77%) obtained promising results. The overall potential of Sentinel-1 interferometric coherence for land cover mapping was evaluated as very good. In all cases, coherence-based results provided higher accuracies than intensity-based strategies, considering 12 days of temporal sampling of the Sentinel-1 A stack. Both coherence and intensity prove to be complementary observables, increasing the overall accuracies in a combined strategy. The accuracy is expected to increase when Sentinel-1 A/B stacks, i.e., six-day sampling, are considered., QC 20200529

Published
2020
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14. Mass balance of the Greenland Ice Sheet from 1992 to 2018

Author

Marine and Atmospheric Research, Sub Dynamics Meteorology, Shepherd, Andrew, Ivins, Erik, Rignot, Eric, Smith, Ben, van den Broeke, Michiel, Velicogna, Isabella, Whitehouse, Pippa, Briggs, Kate, Joughin, Ian, Krinner, Gerhard, Nowicki, Sophie, Payne, Tony, Scambos, Ted, Schlegel, Nicole, Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas, Babonis, Greg, Barletta, Valentina R., Bjørk, Anders A., Blazquez, Alejandro, Bonin, Jennifer, Colgan, William, Csatho, Beata, Cullather, Richard, Engdahl, Marcus E., Felikson, Denis, Fettweis, Xavier, Forsberg, Rene, Hogg, Anna E., Gallee, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian, Hanna, Edward, Harig, Christopher, Helm, Veit, Horvath, Alexander, Horwath, Martin, Khan, Shfaqat, Kjeldsen, Kristian K., Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit, Loomis, Bryant, Luthcke, Scott, McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian, Mohajerani, Yara, Moore, Philip, Mottram, Ruth, Mouginot, Jeremie, Moyano, Gorka, Muir, Alan, Nagler, Thomas, Nield, Grace, Nilsson, Johan, Noël, Brice, Otosaka, Ines, Pattle, Mark E., Peltier, W. Richard, Pie, Nadège, Rietbroek, Roelof, Rott, Helmut, Sørensen, Louise Sandberg, Sasgen, Ingo, Save, Himanshu, Scheuchl, Bernd, Schrama, Ernst, Schröder, Ludwig, Seo, Ki-Weon, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler, Talpe, Matthieu, Tarasov, Lev, Jan van de Berg, Willem, van der Wal, Wouter, van Wessem, Melchior, Vishwakarma, Bramha Dutt, Wiese, David, Wilton, David, Wagner, Thomas, Wouters, Bert, Wuite, Jan, Team, The IMBIE, Marine and Atmospheric Research, Sub Dynamics Meteorology, Shepherd, Andrew, Ivins, Erik, Rignot, Eric, Smith, Ben, van den Broeke, Michiel, Velicogna, Isabella, Whitehouse, Pippa, Briggs, Kate, Joughin, Ian, Krinner, Gerhard, Nowicki, Sophie, Payne, Tony, Scambos, Ted, Schlegel, Nicole, Geruo, A., Agosta, Cécile, Ahlstrøm, Andreas, Babonis, Greg, Barletta, Valentina R., Bjørk, Anders A., Blazquez, Alejandro, Bonin, Jennifer, Colgan, William, Csatho, Beata, Cullather, Richard, Engdahl, Marcus E., Felikson, Denis, Fettweis, Xavier, Forsberg, Rene, Hogg, Anna E., Gallee, Hubert, Gardner, Alex, Gilbert, Lin, Gourmelen, Noel, Groh, Andreas, Gunter, Brian, Hanna, Edward, Harig, Christopher, Helm, Veit, Horvath, Alexander, Horwath, Martin, Khan, Shfaqat, Kjeldsen, Kristian K., Konrad, Hannes, Langen, Peter L., Lecavalier, Benoit, Loomis, Bryant, Luthcke, Scott, McMillan, Malcolm, Melini, Daniele, Mernild, Sebastian, Mohajerani, Yara, Moore, Philip, Mottram, Ruth, Mouginot, Jeremie, Moyano, Gorka, Muir, Alan, Nagler, Thomas, Nield, Grace, Nilsson, Johan, Noël, Brice, Otosaka, Ines, Pattle, Mark E., Peltier, W. Richard, Pie, Nadège, Rietbroek, Roelof, Rott, Helmut, Sørensen, Louise Sandberg, Sasgen, Ingo, Save, Himanshu, Scheuchl, Bernd, Schrama, Ernst, Schröder, Ludwig, Seo, Ki-Weon, Simonsen, Sebastian B., Slater, Thomas, Spada, Giorgio, Sutterley, Tyler, Talpe, Matthieu, Tarasov, Lev, Jan van de Berg, Willem, van der Wal, Wouter, van Wessem, Melchior, Vishwakarma, Bramha Dutt, Wiese, David, Wilton, David, Wagner, Thomas, Wouters, Bert, Wuite, Jan, and Team, The IMBIE

Published
2020

15. Time Series of Sentinel-1 Interferometric Coherence and Backscatter for Crop-Type Mapping

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Mestre-Quereda, Alejandro, Lopez-Sanchez, Juan M., Vicente-Guijalba, Fernando, Jacob, Alexander W., Engdahl, Marcus E., Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Investigación Informática, Mestre-Quereda, Alejandro, Lopez-Sanchez, Juan M., Vicente-Guijalba, Fernando, Jacob, Alexander W., and Engdahl, Marcus E.

Abstract

The potential use of the interferometric coherence measured with Sentinel-1 satellites as input feature for crop classification is explored in this study. A one-year time series of Sentinel-1 images acquired over an agricultural area in Spain, in which 17 crop species are present, is exploited for this purpose. Different options regarding temporal baselines, polarisation, and combination with radiometric data (backscattering coefficient) are analysed. Results show that both radiometric and interferometric features provide notable classification accuracy when used individually (overall accuracy lies between 70% and 80%). It is found that the shortest temporal baseline coherences (6 days) and the use of all available intensity images perform best, hence proving the advantage of the 6-day revisit time provided by the Sentinel-1 constellation with respect to longer revisit times. It is also shown that dual-pol data always provide better classification results than single-pol ones. More importantly, when both coherence and backscattering coefficient are jointly used, a significant increase of accuracy is obtained (greater than 7% in overall accuracy). Individual accuracies of all crop types are increased, and an overall accuracy above 86% is reached. This proves that both features provide complementary information, and that the combination of interferometric and radiometric radar data constitute a solid information source for this application.

Published
2020

16. Sentinel-1 InSAR Coherence for Land Cover Mapping: A Comparison of Multiple Feature-Based Classifiers

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Jacob, Alexander W., Vicente-Guijalba, Fernando, Lopez-Martinez, Carlos, Lopez-Sanchez, Juan M., Litzinger, Marius, Kristen, Harald, Mestre-Quereda, Alejandro, Ziółkowski, Dariusz, Lavalle, Marco, Notarnicola, Claudia, Suresh, Gopika, Antropov, Oleg, Ge, Shaojia, Praks, Jaan, Ban, Yifang, Pottier, Eric, Mallorquí Franquet, Jordi J., Duro, Javier, Engdahl, Marcus E., Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Jacob, Alexander W., Vicente-Guijalba, Fernando, Lopez-Martinez, Carlos, Lopez-Sanchez, Juan M., Litzinger, Marius, Kristen, Harald, Mestre-Quereda, Alejandro, Ziółkowski, Dariusz, Lavalle, Marco, Notarnicola, Claudia, Suresh, Gopika, Antropov, Oleg, Ge, Shaojia, Praks, Jaan, Ban, Yifang, Pottier, Eric, Mallorquí Franquet, Jordi J., Duro, Javier, and Engdahl, Marcus E.

Abstract

This article investigates and demonstrates the suitability of the Sentinel-1 interferometric coherence for land cover and vegetation mapping. In addition, this study analyzes the performance of this feature along with polarization and intensity products according to different classification strategies and algorithms. Seven different classification workflows were evaluated, covering pixel- and object-based analyses, unsupervised and supervised classification, different machine-learning classifiers, and the various effects of distinct input features in the SAR domain—interferometric coherence, backscattered intensities, and polarization. All classifications followed the Corine land cover nomenclature. Three different study areas in Europe were selected during 2015 and 2016 campaigns to maximize diversity of land cover. Overall accuracies (OA), ranging from 70% to 90%, were achieved depending on the study area and methodology, considering between 9 and 15 classes. The best results were achieved in the rather flat area of Doñana wetlands National Park in Spain (OA 90%), but even the challenging alpine terrain around the city of Merano in northern Italy (OA 77%) obtained promising results. The overall potential of Sentinel-1 interferometric coherence for land cover mapping was evaluated as very good. In all cases, coherence-based results provided higher accuracies than intensity-based strategies, considering 12 days of temporal sampling of the Sentinel-1 A stack. Both coherence and intensity prove to be complementary observables, increasing the overall accuracies in a combined strategy. The accuracy is expected to increase when Sentinel-1 A/B stacks, i.e., six-day sampling, are considered.

Published
2020

17. Validating the SAR wavenumber shift principle with the ERS--Envisat PS coherent combination

Author

Perissin, Daniele, Prati, Claudio, Engdahl, Marcus E., and Desnos, Y.L.

Subjects
Remote sensing -- Observations, Synthetic aperture radar -- Usage, Interferometry -- Usage, Business, Earth sciences, Electronics and electrical industries
Abstract

Continuity of the European Remote Sensing Satellite Synthetic Aperture Radar (ERS SAR) archive by means of Envisat Advanced SAR (ASAR) data acquired from March 2002 has introduced the problem of the coherent combination of images coming from sensors with slightly different frequencies. The spectral shift principle states that in case of extended distributed targets, the frequency shift is equivalent to a change of looking angle. In this paper, the same principle is exploited to analyze the behavior of permanent scatterers (PSs) with an extension that is smaller than the ground resolution cell. The conditions under which the PSs identified by ERS can be continued by Envisat are then theoretically determined and experimentally validated. Moreover, this analysis shows that acquisitions characterized by different frequencies can be used to identify the slant-range position of scatterers with high subcell accuracy (tens of centimeters). From the processing side, a very precise images coregistration step is required to get the results described in this paper. Index Terms--Interferometry, synthetic aperture radar (SAR).

Published
2006

18. Land-cover classification using multitemporal ERS-1/2 InSAR data

Author

Engdahl, Marcus E. and Hyyppa, Juha M.

Subjects
Remote sensing -- Research, Synthetic aperture radar -- Research, Business, Earth sciences, Electronics and electrical industries
Abstract

In this study the potential of ERS-1/2 Tandem InSAR data for land-cover classification was investigated at a 2500 [km.sup.2] study area around the Helsinki metropolitan area in Southern Finland. A time-series of 14 ERS-1/2 SAR Tandem image pairs was processed into 28 five-look intensity images, 14 Tandem coherence images and two coherence images with a longer temporal baseline (36 and 246 days). All image data was coregistered and orthorectified into map coordinates using an InSAR DEM. A two-stage hybrid classifier method was employed, where the water-class was classified separately in the first classifier stage, and the remaining classes were classified with an ISODATA classifier. Temporal averaging and Principal Components Transformation (PCT) were used to reduce the number of images fed into ISODATA. Classification accuracy was assessed using high-resolution aerial orthophotos, digital base maps and the Finnish National Forest Inventory (NFI). The overall accuracy for six classes (Field/Open Land, Dense Forest, Sparse Forest, Mixed Urban, Dense Urban, Water) was found to be 90% with kappa coefficient of 0.86. Interferometric coherence carries more land-cover related information than the backscattered intensity. This study confirms that the ERS-1/2 Tandem archives could be exploited for land-cover classification. Index Terms--Interferometric coherence, land-cover classification, principal components transformation, synthetic aperture radar (SAR), synthetic aperture radar (SAR) interferometry, temporal filtering.

Published
2003

20. Sentinel-1 InSAR Coherence for Land Cover Mapping: A Comparison of Multiple Feature-Based Classifiers

Author

Jacob, Alexander W., primary, Vicente-Guijalba, Fernando, additional, Lopez-Martinez, Carlos, additional, Lopez-Sanchez, Juan M., additional, Litzinger, Marius, additional, Kristen, Harald, additional, Mestre-Quereda, Alejandro, additional, Ziolkowski, Dariusz, additional, Lavalle, Marco, additional, Notarnicola, Claudia, additional, Suresh, Gopika, additional, Antropov, Oleg, additional, Ge, Shaojia, additional, Praks, Jaan, additional, Ban, Yifang, additional, Pottier, Eric, additional, Mallorqui Franquet, Jordi Joan, additional, Duro, Javier, additional, and Engdahl, Marcus E., additional

Published
2020
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21. Trends in Antarctic Ice Sheet Elevation and Mass

Author

Shepherd, Andrew, Gilbert, Lin, Muir, Alan, Konrad, Hannes, McMillan, Mal, Slater, Thomas, Briggs, Kate, Sundal, Aud V., Hogg, Anna E., Engdahl, Marcus, Shepherd, Andrew, Gilbert, Lin, Muir, Alan, Konrad, Hannes, McMillan, Mal, Slater, Thomas, Briggs, Kate, Sundal, Aud V., Hogg, Anna E., and Engdahl, Marcus

Abstract

Fluctuations in Antarctic Ice Sheet elevation and mass occur over a variety of timescales, owing to changes in snowfall and ice flow. Here, we disentangle these signals by combining 25 years of satellite radar altimeter observations and a regional climate model. From these measurements, patterns of change that are strongly associated with glaciological events emerge. While the majority of the ice sheet has remained stable, 24% of West Antarctica is now in a state of dynamical imbalance. Thinning of the Pine Island and Thwaites glacier basins reaches 122 m in places, and their rates of ice loss are now five times greater than at the start of our survey. By partitioning elevation changes into areas of snow and ice variability, we estimate that East and West Antarctica have contributed ‐1.1±0.4 and +5.7±0.8 mm to global sea level between 1992 and 2017.

Published
2019

22. Esa Snap - Stamps Integrated Processing for Sentinel-1 Persistent Scatterer Interferometry

Author

Delgado Blasco, Jose Manuel, Fernandez, Diego, Foumelis, Michael, Delgado Blasco, Jose, Desnos, Yves-Louis, Engdahl, Marcus, Fernández, Diego, Veci, Luis, Lu, Jun, Wong, Cecilia, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Agence Spatiale Européenne (ESA), European Space Agency (ESA), Department of Medical Biochemistry and Biophysics, and karolinska institute-Medical Nobel Institute for Biochemistry

Subjects
Synthetic aperture radar, Earth observation, 010504 meteorology & atmospheric sciences, Computer science, Real-time computing, 0211 other engineering and technologies, 02 engineering and technology, Index Terms -Copernicus Sentinel-1, 01 natural sciences, StaMPS, Interferometry, [SDE]Environmental Sciences, Integrated processing, ESA SNAP, Persistent Scatterers Interferometry, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences
Abstract

International audience; Recent development by European Space Agency (ESA) involved the extension of the interferometric capabilities of the SentiNel Application Platform (SNAP) to enable SAR interferometric time series analysis through the Stanford Method of Persistent Scatterer (StaMPS) software package. In the current work, we demonstrate the enabled Persistent Scatterers Interferometry (PSI) processing of Copernicus Sentinel-1 mission data through SNAP-StaMPS integrated processing. A detailed overview of the processing steps involved as well as considerations and assumptions to exploit the SNAP-StaMPS synergy are presented. We intend to support the Earth Observation community by providing guidelines for Sentinel-1 TOPS data PSI processing using open source software packages. We demonstrate the SNAP functionality by processing two stacks of Sentinel-1 products over Mexico City (Mexico) and Rome (Italy).

Published
2018

23. Trends in Antarctic Ice Sheet Elevation and Mass

Author

Shepherd, Andrew, primary, Gilbert, Lin, additional, Muir, Alan S., additional, Konrad, Hannes, additional, McMillan, Malcolm, additional, Slater, Thomas, additional, Briggs, Kate H., additional, Sundal, Aud V., additional, Hogg, Anna E., additional, and Engdahl, Marcus E., additional

Published
2019
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25. Sincohmap: land-cover and vegetation mapping using multi-temporal sentinel-1 interferometric coherence

Author

Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. RSLAB - Grup de Recerca en Teledetecció, Vicente Guijalba, Fernando, Jacob, Alexander, López-Sánchez, Juan Manuel, López Martínez, Carlos, Duro Calvo, Javier, Notarnicola, Claudia, Ziolkowski, Dariusz, Mestre Quereda, Alejandro, Pottier, Eric, Mallorquí Franquet, Jordi Joan, Lavalle, Marco, Engdahl, Marcus, Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. RSLAB - Grup de Recerca en Teledetecció, Vicente Guijalba, Fernando, Jacob, Alexander, López-Sánchez, Juan Manuel, López Martínez, Carlos, Duro Calvo, Javier, Notarnicola, Claudia, Ziolkowski, Dariusz, Mestre Quereda, Alejandro, Pottier, Eric, Mallorquí Franquet, Jordi Joan, Lavalle, Marco, and Engdahl, Marcus

Abstract

InSAR coherence is a promising parameter for land-cover classification and mapping. The ESA SEOM SInCohMap project is devised to test and analyze multi-temporal InSAR coherence potentialities exploiting dense multitemporal data from the Sentinel-1 constellation. In the framework of the project, this paper shows the first classification results using machine learning algorithms over a two-year period of InSAR coherence data. The evaluation is performed on the test site of Doñana (Seville, Southwestern Spain), mainly an agricultural area where different land covers can be identified. Classification results exploiting InSAR coherence shows accuracies around 80 % for this site., Peer Reviewed, Postprint (published version)

Published
2018

30. Assessing hypertemporal SENTINEL-1 COHERENCE maps for LAND COVER monitoring

Author

Vicente-Guijalba, F., primary, Duro, J., additional, Notarnicola, C., additional, Jacob, A., additional, Sonnenschein, R., additional, Mallorqui, J.J., additional, Lopez-Martinez, C., additional, Ziolkowski, D., additional, Hoscilo, A., additional, Dabrowska-Zielinska, K., additional, Bochenek, Z., additional, Pottier, E., additional, Lavalle, M., additional, Lopez-Sanchez, J.M., additional, and Engdahl, Marcus, additional

Published
2017
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31. The Use of ERS-1/2 Tandem Interferometric Coherence in the Estimation of Agricultural Crop Heights

Author

Engdahl, Marcus E., Borgeaud, Maurice, and Rast, Michael

Subjects
Agricultural estimating and reporting -- Methods, Crops -- Forecasts and trends, Interferometry -- Methods, Interferometers -- Usage, Business, Earth sciences, Electronics and electrical industries
Abstract

In this study, the relationship between ERS-1/2 SAR Tandem interferometric coherence and the height of sugar beet, potato, and winter wheat is investigated using measurements of crop growth and coherence. The development of both coherence and crop height is observed to be approximately linear during the early growing season, and linear crop-specific relationships between tandem coherence and the heights of the studied crops are derived. The coherence of all the studied crops decreases as the crop heights increase, a probable explanation for this is that as the crop grows, it screens the ground more effectively, and a greater part of the incident radar energy is backscattered from vegetation that decorrelates more rapidly than the more stable soil. The relatively dense canopies of the root crops sugar beet and potato screen the ground considerably more effectively than the cereal crop winter wheat. This study gives a strong indication that ERS-1/2 Tandem interferometric coherence is related to the height of agricultural crops, and that this relationship can be used to retrieve crop heights.

Published
2001

32. The Seasonal Behavior of Interferometric Coherence in Boreal Forest

Author

Koskinen, Jarkko T., Pulliainen, Jouni T., Hyyppa, Juha M., Engdahl, Marcus E., and Hallikainen, Martti T.

Subjects
Mathematical models -- Usage, Remote sensing -- Usage, Interferometry -- Usage, Forests and forestry -- Analysis, Synthetic aperture radar -- Image quality, Imaging systems -- Usage, Business, Earth sciences, Electronics and electrical industries
Abstract

The capability of SAR interferometry has been previously demonstrated in various applications. In particular, the use of interferometric coherence has shown promising results in forest monitoring, however, mainly in discriminating forested and nonforested areas. We have collected ERS-1 and ERS-2 Tandem data from two Boreal forest test sites in Finland. The data have been processed into interferometric coherence and intensity images. These images have been used to a) compare the behavior of interferometric coherence and intensity for various land-use and forest classes and b) extensive analysis on the behavior of interferometric coherence in Boreal forests as a function of stem volume. Based on the observations and the use of a Boreal forest semi-empirical backscattering model, we have developed an empirical model that describes interferometric coherence of Boreal forests using backscattering information. The results indicate that coherence is more sensitive to the stem volume than the C-band backscattering intensity. However, the intensity and coherence data contain complementary information and therefore, the use of both data sources is beneficial in the observation of Boreal forest. Index Terms--Boreal forest, coherence, interferometry, modeling, synthetic aperture radar (SAR).

Published
2001

33. The Sentinel-1 Toolbox

Author

Veci, Luis, Prats-Iraola, Pau, Scheiber, Rolf, Collard, Fabrice, Fomferra, Norman, and Engdahl, Marcus

Subjects
Sentinel-1, interferometry, Toolbox, polarimetry
Published
2014

34. Critical success factors : An evaluation to identify strategic capabilities

Author

Cöster, Fredrik, Engdahl, Marcus, and Svensson, Johan

Subjects
Ekonomi och näringsliv, competences, importance, Economics and Business, Strategic capabilities, satisfaction, strategy, resources, critical success factors, Business Administration, Företagsekonomi
Abstract

Background: Strategic capabilities are vital components for organisations to include in their business. Another essential elements in a strategy that can affect the performance of an organisation in both a negative and positive direction are critical success factors. This research will study if it possible to evaluate organisations CSFs in order to see whether a well performed CSF also can be identified as a strategic capability. Purpose: The purpose of this thesis is to evaluate organisations CSF in order to identify strategic capabilities Research question: What CSFs can be identified? Which CSFs are identified as strategic capabilities? Methodology: This thesis involved a qualitative pre-study consistent of a content analysis and semi-structured interview that were used to provide measurements to the quantitative survey. Conclusion: The findings indicate that it is possible to identify strategic capabilities by evaluating CSFs. In this study transportation, number of stores and the atmosphere were considered as strategic capabilities.

Published
2014

37. Kommunikation och stress på demensboende : - En intervju- och observationsstudie av vårdgivares kommunikation medvarandra

Author

Engdahl, Marcus and Stenberg, Sofie

Subjects
stress, risk communication, dementia care, communication, kommunikation, demensboende, riskkommunikation
Abstract

Enligt litteraturen är kommunikation en viktig komponent för att undvika incidenter. Syftet var att belysa vikten av kommunikation vid förflyttning, studera hur vårdgivarna reagerar av tidsstressen och hur stressen inverkar på kommunikationen samt jämföra resultatet från denna studie med en tidigare av författarna. Därför har följande frågeställningar valts: 1) Hur kommunicerar vårdgivarna med varandra vid förflyttning av vårdtagare? 2) Inverkar tidsstress kommunikationen? 3) Är det någon skillnad på kommunikationsmönstret mellan två erfarna vårdgivare och mellan en erfaren och en mindre erfaren vårdgivare? Fem semi- strukturerade intervjuer och en observationsstudie genomfördes, följt av en tematisering. Intervju-deltagarna var fyra erfarna undersköterskor och en undersköterskeelev. Resultaten visade att vårdgivarna använde dubbelkommunikation, där de indirekt informerade varandra via den boende. Det var även mycket av arbetet som gick på rutin och därför inte krävde mycket direkt kommunikation mellan vårdgivarna. Att vara på “samma nivå” och räkna innan en förflyttning är en mycket viktig del av kommunikationen. Stressen upplevdes vara låg, något som kan bero på mångårig erfarenhet inom yrket. Slutsatsen blev att mycket av det som pågick vilade på beprövad praxis, vilket gav effekter på hur personalen kommunicerade och upplevde stressen. Många av dem som jobbade på äldreboendet hade jobbat ihop i flera år. Därmed reducerades instruerandet. Då vårdgivarna inte upplevde stressen som ett problem, upplevde de inte heller att kommunikationen influerades. Resultatet som framkom verifierades genom tre uppföljande intervjuer på två andra demensboenden. De teorier som föreslagits fick stöd i de uppföljande intervjuerna baserade på scenarios från den första tematiseringen. According to the literature, communication is a vital component to avoid incidents. The aim was to illuminate the importance of communication during transport, to study how caregivers are influenced by time related stress, and how being stressed for time influences communication and to compare the result from this study with an earlier by the same authors. Therefore the following issues were chosen: 1) How caregivers communicate with each other during transport of the care-taker 2) Does time related to stress influence communication? 3) Is there any difference in communication-pattern between two experienced caregivers and one experienced and one less experienced caregivers? Five semi-structured interviews and an observational study were conducted, followed by thematic analysis. The interview participants consisted of four experienced caregivers and a trainee. The results show that the caregivers used double communication, where they indirectly informed each other through the care recipient. A great deal of work was spent on routine and therefore communication between the caregivers was not required. To be on "the same level" and to count before a transport was an important part of communication. Experiencing low stress was something that may had come with years of experience. The conclusion was that a great deal of what was going on was supported by reliable praxis, which affected how the caregivers communicated and experienced the stress level. Many of those who worked the geriatric care had worked together for years. Consequently the need for instructions was reduced. Since the caregivers did not experience stress as a problem, neither did they experience that communication was influenced. These results were further verified in three follow-up interviews at two other dementia care facilities. The theories proposed were supported by the follow-up interviews which were based on analyses from the observation. Godkänt

Published
2013

43. Phase Unwrapping in SAR Interferometry Using Instantaneous Frequency Estimation

Author

Herland, Einar-Arne, Teknillinen korkeakoulu, Helsinki University of Technology, Teknillisen fysiikan ja matematiikan osasto, Simula, Olli, Engdahl, Marcus, Herland, Einar-Arne, Teknillinen korkeakoulu, Helsinki University of Technology, Teknillisen fysiikan ja matematiikan osasto, Simula, Olli, and Engdahl, Marcus

Published
1996

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