30 results on '"Alan Muir"'
Search Results
2. The Roles of the S3MPC: Monitoring, Validation and Evolution of Sentinel-3 Altimetry Observations
- Author
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Graham D. Quartly, Francesco Nencioli, Matthias Raynal, Pascal Bonnefond, Pablo Nilo Garcia, Albert Garcia-Mondéjar, Adrián Flores de la Cruz, Jean-Francois Crétaux, Nicolas Taburet, Marie-Laure Frery, Mathilde Cancet, Alan Muir, David Brockley, Malcolm McMillan, Saleh Abdalla, Sara Fleury, Emeline Cadier, Qi Gao, Maria Jose Escorihuela, Mònica Roca, Muriel Bergé-Nguyen, Olivier Laurain, Jérôme Bruniquel, Pierre Féménias, and Bruno Lucas
- Subjects
altimeter ,calibration ,validation ,Copernicus/Sentinel-3 ,microwave radiometer ,ocean ,Science - Abstract
The Sentinel-3 Mission Performance Centre (S3MPC) is tasked by the European Space Agency (ESA) to monitor the health of the Copernicus Sentinel-3 satellites and ensure a high data quality to the users. This paper deals exclusively with the effort devoted to the altimeter and microwave radiometer, both components of the Surface Topography Mission (STM). The altimeters on Sentinel-3A and -3B are the first to operate in delay-Doppler or SAR mode over all Earth surfaces, which enables better spatial resolution of the signal in the along-track direction and improved noise reduction through multi-looking, whilst the radiometer is a two-channel nadir-viewing system. There are regular routine assessments of the instruments through investigation of telemetered housekeeping data, calibrations over selected sites and comparisons of geophysical retrievals with models, in situ data and other satellite systems. These are performed both to monitor the daily production, assessing the uncertainties and errors on the estimates, and also to characterize the long-term performance for climate science applications. This is critical because an undetected drift in performance could be misconstrued as a climate variation. As the data are used by the Copernicus Services (e.g., CMEMS, Global Land Monitoring Services) and by the research community over open ocean, coastal waters, sea ice, land ice, rivers and lakes, the validation activities encompass all these domains, with regular reports openly available. The S3MPC is also in charge of preparing improvements to the processing, and of the development and tuning of algorithms to improve their accuracy. This paper is thus the first refereed publication to bring together the analysis of SAR altimetry across all these different domains to highlight the benefits and existing challenges.
- Published
- 2020
- Full Text
- View/download PDF
3. Alfred Maurice Binnie, F. Eng. 6 February 1901-31 December 1986
- Author
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Wood, Alan Muir
- Published
- 1997
4. Brief communication: Ice sheet elevation measurements from the Sentinel-3A and Sentinel-3B tandem phase
- Author
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Alan Muir, Malcolm McMillan, and Craig Donlon
- Subjects
QE1-996.5 ,geography ,Accuracy and precision ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Tandem ,0211 other engineering and technologies ,Elevation ,Geology ,Terrain ,02 engineering and technology ,01 natural sciences ,Environmental sciences ,Phase (matter) ,GE1-350 ,Satellite ,Altimeter ,Ice sheet ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Water Science and Technology ,Remote sensing - Abstract
Over the coming decade, the quartet of Copernicus Sentinel-3 satellite altimeters will provide a continuous record of ice sheet elevation change. Ensuring consistency of measurement between the four satellites requires rigorous in-flight inter-comparison. To facilitate this, Sentinel-3B was initially flown in a unique tandem formation with Sentinel-3A, enabling near-instantaneous, co-located measurements of surface elevation to be acquired. Here, we analyse tandem measurements of ice sheet elevation, to show that both instruments operate with statistically equivalent accuracy and precision, even over complex ice margin terrain. This analysis demonstrates that both satellites can be used interchangeably to study ice sheet evolution.
- Published
- 2021
5. Geoffrey Morse Binnie. 13 November 1908-5 April 1989
- Author
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Wood, Alan Muir
- Published
- 1990
6. The Roles of the S3MPC: Monitoring, Validation and Evolution of Sentinel-3 Altimetry Observations
- Author
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Adrian Flores de la Cruz, Graham D. Quartly, Sara Fleury, Matthias Raynal, Qi Gao, O. Laurain, Pierre Féménias, Albert Garcia-Mondejar, Maria Jose Escorihuela, Pablo Nilo Garcia, Jerome Bruniquel, Emeline Cadier, Marie Laure Frery, Francesco Nencioli, Monica Roca, Pascal Bonnefond, Saleh Abdalla, Alan Muir, David Brockley, Mathilde Cancet, Jean Francois Cretaux, Nicolas Taburet, Muriel Berge-Nguyen, Bruno Manuel Lucas, Malcolm McMillan, Systèmes de Référence Temps Espace (SYRTE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), and Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010504 meteorology & atmospheric sciences ,0211 other engineering and technologies ,02 engineering and technology ,01 natural sciences ,altimeter ,microwave radiometer ,Sea ice ,Cryosphere ,Copernicus/Sentinel-3 ,Altimeter ,lcsh:Science ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing ,validation ,[PHYS]Physics [physics] ,geography ,Radiometer ,geography.geographical_feature_category ,Microwave radiometer ,Mode (statistics) ,calibration ,ocean ,13. Climate action ,Data quality ,General Earth and Planetary Sciences ,Environmental science ,Satellite ,lcsh:Q ,coastal zone ,cryosphere ,radar transponders ,model comparison ,buoys ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
International audience; The Sentinel-3 Mission Performance Centre (S3MPC) is tasked by the European Space Agency (ESA) to monitor the health of the Copernicus Sentinel-3 satellites and ensure a high data quality to the users. This paper deals exclusively with the effort devoted to the altimeter and microwave radiometer, both components of the Surface Topography Mission (STM). The altimeters on Sentinel-3A and -3B are the first to operate in delay-Doppler or SAR mode over all Earth surfaces, which enables better spatial resolution of the signal in the along-track direction and improved noise reduction through multi-looking, whilst the radiometer is a two-channel nadir-viewing system. There are regular routine assessments of the instruments through investigation of telemetered housekeeping data, calibrations over selected sites and comparisons of geophysical retrievals with models, in situ data and other satellite systems. These are performed both to monitor the daily production, assessing the uncertainties and errors on the estimates, and also to characterize the long-term performance for climate science applications. This is critical because an undetected drift in performance could be misconstrued as a climate variation. As the data are used by the Copernicus Services (e.g., CMEMS, Global Land Monitoring Services) and by the research community over open ocean, coastal waters, sea ice, land ice, rivers and lakes, the validation activities encompass all these domains, with regular reports openly available. The S3MPC is also in charge of preparing improvements to the processing, and of the development and tuning of algorithms to improve their accuracy. This paper is thus the first refereed publication to bring together the analysis of SAR altimetry across all these different domains to highlight the benefits and existing challenges.
- Published
- 2020
7. Mass balance of the Antarctic Ice Sheet from 1992 to 2017
- Author
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Ted Scambos, Richard I. Cullather, Helmut Rott, David N. Wiese, Valentina R. Barletta, Isabella Velicogna, Brice Noël, Jeremie Mouginot, Edward Hanna, Melchior van Wessem, W. Richard Peltier, Thomas Nagler, Alejandro Blazquez, Eric Rignot, Jennifer Bonin, Nadege Pie, Veit Helm, Bernd Scheuchl, Louise Sandberg-Sørensen, Brian Gunter, Ines Otosaka, Ben Smith, Denis Felikson, Benoit S. Lecavalier, Bryant D. Loomis, Cécile Agosta, Peter L. Langen, Wouter van der Wal, Christopher Harig, René Forsberg, Philip Moore, Giorgio Spada, Ernst Schrama, Alex S. Gardner, T. C. Sutterley, Matthieu Talpe, Daniele Melini, Xavier Fettweis, Andreas Groh, Gerhard Krinner, Bert Wouters, Sebastian H. Mernild, Kate Briggs, Andreas P. Ahlstrøm, Erik R. Ivins, Shfaqat Abbas Khan, Johan Nilsson, Hannes Konrad, Nicole Schlegel, Sebastian B. Simonsen, Kristian K. Kjeldsen, Greg Babonis, Malcolm McMillan, Pippa L. Whitehouse, Ingo Sasgen, Lev Tarasov, Ki-Weon Seo, Lin Gilbert, Geruo A, Yara Mohajerani, Scott B. Luthcke, Gorka Moyano, Andrew Shepherd, Thomas Slater, Michiel R. van den Broeke, Bramha Dutt Vishwakarma, Roelof Rietbroek, Alexander Horvath, Hubert Gallée, Tony Payne, Willem Jan van de Berg, Martin Horwath, Alan Muir, Ian Joughin, Beata Csatho, Himanshu Save, Mark E. Pattle, Sophie Nowicki, Ludwig Schröder, Grace A. Nield, Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Andrew Shepherd, Erik Ivin, Eric Rignot, Ben Smith, Michiel VDBroeke, Isabella Velicogna, Pippa Whitehouse, Kate Brigg, Ian Joughin, Gerhard Krinner, Sophie Nowicki, Tony Payne, Ted Scambo, Nicole Schlegel, Geruo A, Cécile Agosta, Andreas Ahlstrøm, Greg Baboni, Valentina Barletta, Alejandro Blazquez, Jennifer Bonin, Beata Csatho, Richard Cullather, Denis Felikson, Xavier Fettwei, Rene Forsberg, Hubert Gallee, Alex Gardner, Lin Gilbert, Andreas Groh, Brian Gunter, Edward Hanna, Christopher Harig, Veit Helm, Alexander Horvath, Martin Horwath, Shfaqat Khan, Kristian Kjeldsen, Hannes Konrad, Peter Langen, Benoit Lecavalier, Bryant Loomi, Scott Luthcke, Malcolm McMillan, Daniele Melini, Sebastian Mernild, Yara Mohajerani, Philip Moore, Jeremie Mouginot, Gorka Moyano, Alan Muir, Thomas Nagler, Grace Nield, Johan Nilsson, Brice Noel, Ines Otosaka, Mark Pattle, William Peltier, Nadege Pie, Roelof Rietbroek, Helmut Rott, LouiseSandberg Sørensen, Ingo Sasgen, Himanshu Save, Bernd Scheuchl, Ernst Schrama, Ludwig Schröder, KiWeon Seo, Sebastian Simonsen, Tom Slater, Giorgio Spada, Tyler Sutterley, Matthieu Talpe, Lev Tarasov, Willem JVdeBerg, Wouter vanderWal, Melchior van Wessem, BramhaDutt Vishwakarma, David Wiese, Bert Wouters, Centre National de la Recherche Scientifique (CNRS), University of California [Irvine] (UCI), University of California, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)
- Subjects
010504 meteorology & atmospheric sciences ,[SDE.MCG]Environmental Sciences/Global Changes ,Climate change ,Antarctic ice sheet ,NN ,010502 geochemistry & geophysics ,01 natural sciences ,Glacier mass balance ,Peninsula ,Taverne ,SDG 13 - Climate Action ,F890 Geographical and Environmental Sciences not elsewhere classified ,Sea level ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Post-glacial rebound ,Balance (accounting) ,13. Climate action ,[SDE]Environmental Sciences ,Environmental science ,Physical geography ,Tonne - Abstract
The Antarctic Ice Sheet is an important indicator of climate change and driver of sea-level rise. Here we combine satellite observations of its changing volume, flow and gravitational attraction with modelling of its surface mass balance to show that it lost 2,720 ± 1,390 billion tonnes of ice between 1992 and 2017, which corresponds to an increase in mean sea level of 7.6 ± 3.9 millimetres (errors are one standard deviation). Over this period, ocean-driven melting has caused rates of ice loss from West Antarctica to increase from 53 ± 29 billion to 159 ± 26 billion tonnes per year; ice-shelf collapse has increased the rate of ice loss from the Antarctic Peninsula from 7 ± 13 billion to 33 ± 16 billion tonnes per year. We find large variations in and among model estimates of surface mass balance and glacial isostatic adjustment for East Antarctica, with its average rate of mass gain over the period 1992–2017 (5 ± 46 billion tonnes per year) being the least certain.
- Published
- 2018
8. A new digital elevation model of Antarctica derived from CryoSat-2 altimetry
- Author
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Hannes Konrad, Lin Gilbert, Tommaso Parrinello, Malcolm McMillan, Thomas Slater, Andrew Shepherd, Anna E. Hogg, and Alan Muir
- Subjects
lcsh:GE1-350 ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,lcsh:QE1-996.5 ,Mode (statistics) ,Elevation ,Antarctic ice sheet ,010502 geochemistry & geophysics ,Geodesy ,01 natural sciences ,Ice shelf ,lcsh:Geology ,Kriging ,Altimeter ,Ice sheet ,Digital elevation model ,Geology ,lcsh:Environmental sciences ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Water Science and Technology ,Remote sensing - Abstract
We present a new digital elevation model (DEM) of the Antarctic ice sheet and ice shelves based on 2.5×108 observations recorded by the CryoSat-2 satellite radar altimeter between July 2010 and July 2016. The DEM is formed from spatio-temporal fits to elevation measurements accumulated within 1, 2, and 5 km grid cells, and is posted at the modal resolution of 1 km. Altogether, 94 % of the grounded ice sheet and 98 % of the floating ice shelves are observed, and the remaining grid cells north of 88∘ S are interpolated using ordinary kriging. The median and root mean square difference between the DEM and 2.3×107 airborne laser altimeter measurements acquired during NASA Operation IceBridge campaigns are −0.30 and 13.50 m, respectively. The DEM uncertainty rises in regions of high slope, especially where elevation measurements were acquired in low-resolution mode; taking this into account, we estimate the average accuracy to be 9.5 m – a value that is comparable to or better than that of other models derived from satellite radar and laser altimetry.
- Published
- 2019
9. A new digital elevation model of Antarctica derived from CryoSat-2 altimetry
- Author
-
Thomas Slater, Andrew Shepherd, Malcolm McMillan, Alan Muir, Lin Gilbert, Anna E. Hogg, Hannes Konrad, and Tommaso Parrinello
- Abstract
We present a new Digital Elevation Model (DEM) of the Antarctic ice sheet and ice shelves based on 2.5 × 108 observations recorded by the CryoSat-2 satellite radar altimeter between July 2010 and July 2016. The DEM is formed from spatio-temporal fits to elevation measurements accumulated within 1, 2 and 5 km grid cells, and is posted at the modal resolution of 1 km. Altogether, 94 % of the grounded ice sheet and 98 % of the floating ice shelves are observed, and the remaining grid cells North of 88° S are interpolated using ordinary kriging. The median and root mean square difference between the DEM and 2.3 × 107 airborne laser altimeter measurements acquired during NASA Operation IceBridge campaigns are −0.30 m and 13.50 m, respectively. The DEM uncertainty rises in regions of high slope – especially where elevation measurements were acquired in Low Resolution Mode – and, taking this into account, we estimate the average accuracy to be 9.5 m – a value that is comparable to or better than that of other models derived from satellite radar and laser altimetry.
- Published
- 2018
10. Net retreat of Antarctic glacier grounding lines
- Author
-
Thomas Slater, Malcolm McMillan, Hannes Konrad, Lin Gilbert, Andrew Shepherd, Anna E. Hogg, and Alan Muir
- Subjects
geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Grounding line ,Thinning ,Glacier ,Last Glacial Maximum ,STREAMS ,Forcing (mathematics) ,010502 geochemistry & geophysics ,01 natural sciences ,Satellite altimeter ,Peninsula ,General Earth and Planetary Sciences ,14. Life underwater ,Physical geography ,Geology ,0105 earth and related environmental sciences - Abstract
Grounding lines are a key indicator of ice-sheet instability, because changes in their position reflect imbalance with the surrounding ocean and affect the flow of inland ice. Although the grounding lines of several Antarctic glaciers have retreated rapidly due to ocean-driven melting, records are too scarce to assess the scale of the imbalance. Here, we combine satellite altimeter observations of ice-elevation change and measurements of ice geometry to track grounding-line movement around the entire continent, tripling the coverage of previous surveys. Between 2010 and 2016, 22%, 3% and 10% of surveyed grounding lines in West Antarctica, East Antarctica and at the Antarctic Peninsula retreated at rates faster than 25 m yr−1 (the typical pace since the Last Glacial Maximum) and the continent has lost 1,463 km2 ± 791 km2 of grounded-ice area. Although by far the fastest rates of retreat occurred in the Amundsen Sea sector, we show that the Pine Island Glacier grounding line has stabilized, probably as a consequence of abated ocean forcing. On average, Antarctica’s fast-flowing ice streams retreat by 110 metres per metre of ice thinning. Grounding lines in parts of West Antarctica, East Antarctica and the Antarctic Peninsula retreated faster than typical post-glacial pace, according to satellite observations and ice geometry measurements.
- Published
- 2018
11. A safety cultured tunnelling
- Author
-
Wood, Alan Muir
- Subjects
Tunneling -- Safety and security measures ,Tunneling -- Methods ,Business ,Construction and materials industries - Published
- 2007
12. II. FUNDAMENTALS: UNDERNEATH AND BEHIND THE CITY
- Author
-
WOOD, ALAN MUIR
- Published
- 1985
13. ESA's Ice Sheets CCI: validation and inter-comparison of surface elevation changes derived from laser and radar altimetry over Jakobshavn Isbræ, Greenland – Round Robin results
- Author
-
Andrew Shepherd, Marcel Kleinherenbrink, Louise Sandberg Sørensen, Roderik Lindenbergh, Nadege Pie, Alan Muir, Denis Felikson, Brian Gunter, Francesca Ticconi, Thomas Flament, René Forsberg, R. T. W. L. Hurkmans, Joanna Fredenslund Levinsen, Geir Moholdt, and K. Khvorostovsky
- Subjects
geography ,geography.geographical_feature_category ,Elevation ,Climate change ,Greenland ice sheet ,Laser ,law.invention ,law ,SDG 13 - Climate Action ,Altimeter ,Radar ,Ice sheet ,Geology ,Radar altimetry ,Remote sensing - Abstract
In order to increase the understanding of the changing climate, the European Space Agency has launched the Climate Change Initiative (ESA CCI), a program which joins scientists and space agencies into 13 projects either affecting or affected by the concurrent changes. This work is part of the Ice Sheets CCI and four parameters are to be determined for the Greenland Ice Sheet (GrIS), each resulting in a dataset made available to the public: Surface Elevation Changes (SEC), surface velocities, grounding line locations, and calving front locations. All CCI projects have completed a so-called Round Robin exercise in which the scientific community was asked to provide their best estimate of the sought parameters as well as a feedback sheet describing their work. By inter-comparing and validating the results, obtained from research institutions world-wide, it is possible to develop the most optimal method for determining each parameter. This work describes the SEC Round Robin and the subsequent conclusions leading to the creation of a method for determining GrIS SEC values. The participants used either Envisat radar or ICESat laser altimetry over Jakobshavn Isbræ drainage basin, and the submissions led to inter-comparisons of radar vs. altimetry as well as cross-over vs. repeat-track analyses. Due to the high accuracy of the former and the high spatial resolution of the latter, a method, which combines the two techniques will provide the most accurate SEC estimates. The data supporting the final GrIS analysis stem from the radar altimeters on-board Envisat, ERS-1 and ERS-2. The accuracy of laser data exceeds that of radar altimetry; the Round Robin analysis has, however, proven the latter equally capable of dealing with surface topography thereby making such data applicable in SEC analyses extending all the way from the interior ice sheet to margin regions. This shows good potential for a~future inclusion of ESA CryoSat-2 and Sentinel-3 radar data in the analysis, and thus for obtaining reliable SEC estimates throughout the entire GrIS.
- Published
- 2013
14. A reconciled estimate of ice-sheet mass balance
- Author
-
Duncan A. Young, Julien P. Nicolas, Natalia Galin, Martin Horwath, David H. Bromwich, Andrew Shepherd, Michiel R. van den Broeke, Valentina R. Barletta, Ian Joughin, Michael J. Bentley, John Wahr, Jeremie Mouginot, Duncan J. Wingham, Stefan R. M. Ligtenberg, Hamish D. Pritchard, Willem Jan van de Berg, Jilu Li, Antony J. Payne, Ted Scambos, Jan T. M. Lenaerts, René Forsberg, Louise Sandberg Sørensen, S. S. Jacobs, Pippa L. Whitehouse, Isabella Velicogna, Scott B. Luthcke, Ernst Schrama, Glenn A. Milne, Eric Rignot, Rakia Meister, Malcolm McMillan, Ben Smith, Donghui Yi, Alan Muir, Aud Venke Sundal, Helmut Rott, Srinivas Bettadpur, Erik R. Ivins, Kate Briggs, Bernd Scheuchl, John Paden, Geruo A, H. Jay Zwally, Jan H. van Angelen, David G. Vaughan, Adrian Luckman, and Matt A. King
- Subjects
geography ,Multidisciplinary ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Mass distribution ,Meteorology ,Climate Change ,Greenland ,Antarctic Regions ,Climate change ,Glacier ,Post-glacial rebound ,010502 geochemistry & geophysics ,Snow ,Geodesy ,01 natural sciences ,Glacier mass balance ,13. Climate action ,Geographic Information Systems ,Ice Cover ,Gravimetry ,Ice sheet ,Geology ,0105 earth and related environmental sciences - Abstract
Warming and Melting Mass loss from the ice sheets of Greenland and Antarctica account for a large fraction of global sea-level rise. Part of this loss is because of the effects of warmer air temperatures, and another because of the rising ocean temperatures to which they are being exposed. Joughin et al. (p. 1172 ) review how ocean-ice interactions are impacting ice sheets and discuss the possible ways that exposure of floating ice shelves and grounded ice margins are subject to the influences of warming ocean currents. Estimates of the mass balance of the ice sheets of Greenland and Antarctica have differed greatly—in some cases, not even agreeing about whether there is a net loss or a net gain—making it more difficult to project accurately future sea-level change. Shepherd et al. (p. 1183 ) combined data sets produced by satellite altimetry, interferometry, and gravimetry to construct a more robust ice-sheet mass balance for the period between 1992 and 2011. All major regions of the two ice sheets appear to be losing mass, except for East Antarctica. All told, mass loss from the polar ice sheets is contributing about 0.6 millimeters per year (roughly 20% of the total) to the current rate of global sea-level rise.
- Published
- 2012
15. Thomas Young and the Brunels: masters of masonry analysis.
- Author
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Wood, Alan Muir
- Subjects
- *
MASONRY , *ENGINEERS , *ELASTICITY , *ENGINEERING design , *BRIDGE design & construction , *TUNNEL design & construction - Abstract
Recent examples of inappropriate analysis of masonry structures, leading to their unnecessary designation as unsafe, suggest modern engineers could benefit from a wider appreciation of elementary principles. The 1820s procedure of Thomas Young - perhaps best remembered for his modulus of elasticity - is a good place to start. This paper sets out the principles of Young's visionary approach and how it was adopted and developed by Isambard Kingdom Brunel for his record-breaking Maidenhead Bridge over the River Thames in England. It also speculates how Brunel's father Marc Isambard may have further developed the method for assessing his Thames Tunnel design. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
16. Self-Confident Engineer
- Author
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Wood, Alan Muir
- Published
- 1994
17. A question (and answer) of standards
- Author
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Wood, Alan Muir
- Subjects
Business ,Business, international - Abstract
Dear Sir In his 2004 Harding Lecture, Sir Alan Muir Wood took issue with some of the guidance in Clause 11 of BS 6164:2001, which relates to compressed air tunnelling. [...]
- Published
- 2005
18. Colin Kirkland, 1936-2004
- Author
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Wood, Alan Muir
- Subjects
Kirkland, Colin ,Business ,Business, international - Abstract
Through the unexpected death by cancer of Colin Kirkland, on 23 December 2004, the tunnelling community has lost one of its most eminent, active and esteemed members, in Britain, and [...]
- Published
- 2005
19. Abbeystead Outfall Works: Background to Repairs and Modifications - and Lessons Learned.
- Author
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ORR, W. E., WOOD, SIR ALAN MUIR, BEAVER, J. L., IRELAND, R. J., and BEAGLEY, D. P.
- Published
- 1991
- Full Text
- View/download PDF
20. LONDON UNDER LONDON: A Subterranean Guide Richard Trent Ellis Hillman
- Author
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WOOD, ALAN MUIR
- Published
- 1986
21. BUILDING CONSTRUCTION BEFORE MECHANIZATION John Fitchen
- Author
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WOOD, ALAN MUIR
- Published
- 1987
22. Tunnelling : Management by Design
- Author
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Alan Muir Wood and Alan Muir Wood
- Subjects
- Tunneling, Tunnels--Design and construction
- Abstract
Tunnelling has become a fragmented process, excessively influenced by lawyers'notions of confrontational contractual bases. This prevents the pooling of skills, essential to the achievement of the promoters'objectives. Tunnelling: Management by Design seeks the reversal of this trend. After a brief historical treatment of selected developments, th
- Published
- 2000
23. The channel tunnel—View of a teredo
- Author
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Wood, Sir Alan Muir
- Published
- 1991
- Full Text
- View/download PDF
24. Abbeystead Outfall Works: background to repairs and modifications-and lessons learned
- Author
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Beagley, D. P. D. P. Beagley, Ireland, R. J., Beaver, J. L., Orr, W. E., and Wood, Alan Muir
- Subjects
PLANTS - Published
- 1991
25. Technological Aspects of Subsurface Use in Developing Countries
- Author
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Wood, Alan Muir
- Published
- 1983
26. LETTERS.
- Author
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Bourne, Simon, Donnetti, Mario, Gee, Tony, Besley, Neil, Pritchard, Bob, Biggart, Alastair, Wood, Alan Muir, Cheetham, Brian A., Clark, P., and Laws, David
- Subjects
LETTERS to the editor ,BARRAGES ,LAGOONS ,RAILROADS ,DIVERSION structures (Hydraulic engineering) - Abstract
Several letters to the editor are presented in response to articles in previous issues, including one on the Severn Barrage in the October 4, 2007 issue, another by John McKenna on tidal lagoons in the same issue and a report on the Crossrail project in the October 11, 2007 issue.
- Published
- 2007
27. Letters.
- Author
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Rickard, Charlie, Reed, Alan, Brown, Chris, Wood, Alan Muir, Denness, Bruce, Harris, Alan, Price, David, and McBeth, Douglas
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LETTERS to the editor ,FLOODS ,HIGHWAY law ,CONSTRUCTION industry ,INDUSTRIAL safety - Abstract
Several letters to the editor are presented in response to articles in previous issues including the claim of George Fleming that there is no need for another review of flood risk, a report on the increasing pace of regulation concerning highways use in the July 12, 2007 issue and the increase in construction deaths in line with CDM procedures.
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- 2007
28. Letters.
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Smith, Angela, Wood, Alan Muir, Mansell, Martin, Lovell, Alan, Watson, Chris, Hall, J. W., and Foot, Roy
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LETTERS to the editor ,BUILDINGS & the environment ,CLIMATE change ,EXPLOITATION of humans - Abstract
Several letters to the editor are presented in response to articles in previous issues including one on worker exploitation in the United Arab Emirates in the January 18, 2007 issue, "New Buildings Need to Reflect Climate Change," and the article on Thomas Telford in the January 11, 2007 issue.
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- 2007
29. Chapter 13 - Tunnels in soil and weak rock
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Wood, Sir Alan Muir
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- 1990
- Full Text
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30. Mass balance of the Greenland Ice Sheet from 1992 to 2018
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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
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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.
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- 2020
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