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Ten new insights in climate science 2022
- Maria A. Martin, Emmanuel A. Boakye, Emily Boyd, Wendy Broadgate, Mercedes Bustamante, Josep G. Canadell, Edward R. Carr, Eric K. Chu, Helen Cleugh, Szilvia Csevár, Marwa Daoudy, Ariane de Bremond, Meghnath Dhimal, Kristie L. Ebi, Clea Edwards, Sabine Fuss, Martin P. Girardin, Bruce Glavovic, Sophie Hebden, Marina Hirota, Huang-Hsiung Hsu, Saleemul Huq, Karin Ingold, Ola M. Johannessen, Yasuko Kameyama, Nilushi Kumarasinghe, Gaby S. Langendijk, Tabea Lissner, Shuaib Lwasa, Catherine Machalaba, Aaron Maltais, Manu V. Mathai, Cheikh Mbow, Karen E. McNamara, Aditi Mukherji, Virginia Murray, Jaroslav Mysiak, Chukwumerije Okereke, Daniel Ospina, Friederike Otto, Anjal Prakash, Juan M. Pulhin, Emmanuel Raju, Aaron Redman, Kanta K. Rigaud, Johan Rockström, Joyashree Roy, E. Lisa F. Schipper, Peter Schlosser, Karsten A. Schulz, Kim Schumacher, Luana Schwarz, Murray Scown, Barbora Šedová, Tasneem A. Siddiqui, Chandni Singh, Giles B. Sioen, Detlef Stammer, Norman J. Steinert, Sunhee Suk, Rowan Sutton, Lisa Thalheimer, Maarten van Aalst, Kees van der Geest, Zhirong Jerry Zhao
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- Journal:
- Global Sustainability / Volume 5 / 2022
- Published online by Cambridge University Press:
- 10 November 2022, e20
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Non-technical summary
We summarize what we assess as the past year's most important findings within climate change research: limits to adaptation, vulnerability hotspots, new threats coming from the climate–health nexus, climate (im)mobility and security, sustainable practices for land use and finance, losses and damages, inclusive societal climate decisions and ways to overcome structural barriers to accelerate mitigation and limit global warming to below 2°C.
Technical summaryWe synthesize 10 topics within climate research where there have been significant advances or emerging scientific consensus since January 2021. The selection of these insights was based on input from an international open call with broad disciplinary scope. Findings concern: (1) new aspects of soft and hard limits to adaptation; (2) the emergence of regional vulnerability hotspots from climate impacts and human vulnerability; (3) new threats on the climate–health horizon – some involving plants and animals; (4) climate (im)mobility and the need for anticipatory action; (5) security and climate; (6) sustainable land management as a prerequisite to land-based solutions; (7) sustainable finance practices in the private sector and the need for political guidance; (8) the urgent planetary imperative for addressing losses and damages; (9) inclusive societal choices for climate-resilient development and (10) how to overcome barriers to accelerate mitigation and limit global warming to below 2°C.
Social media summaryScience has evidence on barriers to mitigation and how to overcome them to avoid limits to adaptation across multiple fields.
Satellite archives reveal abrupt changes in behavior of Helheim Glacier, southeast Greenland
- VICTORIA V. MILES, MARTIN W. MILES, OLA M. JOHANNESSEN
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- Journal:
- Journal of Glaciology / Volume 62 / Issue 231 / February 2016
- Published online by Cambridge University Press:
- 07 March 2016, pp. 137-146
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Rapid changes in Helheim Glacier and other Greenland outlet glaciers since 2000 are well-known, but knowledge on earlier decades is fragmentary. Here we exploit the satellite image archives to produce and analyze a monthly-to-seasonal record of Helheim Glacier front position, 1980–2011. Statistical analysis identifies decadal periods with abrupt changes in variability and mean. The record also reveals evidence of volatile advance/retreat behavior in the 1980s. In one of several cases of large-amplitude subannual changes, the glacier front ‘surged’ forward in 1984/85, advancing ~6 km within a few months – surpassing its Little Ice Age maximum position – and afterward retreated ~5 km within a few weeks. These findings challenge the prevailing view of front position stability in the decades before the multi-year retreat in the early 2000s. Cold conditions including rigid ice mélange appear to be a factor in the high-amplitude seasonal advances in the 1980s. However the magnitude and abruptness of the changes in the record cannot be explained solely as a climatic response, such that glacio-dynamics must be invoked. Further, the volatile advance/retreat behavior in the cold 1980s resulted in increased dynamic ice loss, complicating the interpretation of increased calving activity as a response to warming.
Winter navigation in the Northern Sea Route using RADARSAT data
- Vitali Yu. Alexandrov, Stein Sandven, Ola M. Johannessen, Lasse H. Pettersson, Øyvind Dalen
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- Journal:
- Polar Record / Volume 36 / Issue 199 / October 2000
- Published online by Cambridge University Press:
- 27 October 2009, pp. 335-344
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The results are presented of the first winter ice navigation demonstration, using synthetic aperture radar (SAR) images from the Canadian satellite RADARSAT, onboard the nuclear icebreaker Sovetskiy Soyuz in the Kara Sea region in April–May 1998. While ERS SAR data only could cover part of the sea ice in this large area, the demonstration showed that RADARSAT ScanSAR images with 100 m pixel size could be used to map all relevant ice areas with a few 500 × 500 km scenes. SAR images transferred onboard icebreakers in near real time offer an excellent possibility to select optimal sailing routes in difficult ice conditions such as those that were encountered by this expedition. SAR images were also used for planning of operations prior to the expedition. This study compares sub-satellite sea-ice observations with RADARSAT SAR as well as Okean side-looking radar (SLR) signatures of the major ice types and features found in the Kara Sea during winter. Wide-swath SAR images will become available from several new satellites in the near future, such as Envisat, scheduled in 2001, and RADARSAT-2, in 2002. Satellite SAR images will therefore play an increasingly important role in operational ice monitoring both in the Northern Sea Route and in other ice areas.
8 - Sea-ice observations
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- By Seymour W. Laxon, Centre for Polar Observation and Modelling, University College London, John E. Walsh, Department of Atmospheric Sciences, University of Illinois, Peter Wadhams, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Ola M. Johannessen, Nansen Environmental and Remote Sensing Center, Bergen, Martin Miles, Nansen Environmental and Remote Sensing Center, Bergen
- Edited by Jonathan L. Bamber, University of Bristol, Antony J. Payne, University of Bristol
- Foreword by John Houghton
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- Book:
- Mass Balance of the Cryosphere
- Published online:
- 16 October 2009
- Print publication:
- 12 February 2004, pp 337-366
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Summary
Introduction
The Earth's climate system is presently undergoing an uncontrolled experiment as a result of man's increasing emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and other greenhouse gases – gases that exert a positive radiative forcing of climate – into the atmosphere, as well as anthropogenic aerosols (microscopic particles) that have a negative radiative forcing. As a net result of these forcings and associated dynamics, changes in global mean temperature are predicted to exceed their natural variability between the decades 1980 and 2010 (Cubasch et al., 1995). An assessment by the Intergovernmental Panel on Climate Change (IPCC) concluded cautiously that the balance of observational evidence already suggests a discernible human influence on the global climate (IPCC, 1995).
As a complement to observational studies, numerical models are used to understand better climate and climate change, including the effect of anthropogenic emissions of greenhouse gases and aerosols. The most advanced climate models are coupled oceanic and atmospheric general circulation models (GCMs). These models simulate the climate system based on physical laws describing the dynamics and physics of the ocean and atmosphere, and include representations of land–surface processes and other complex processes including those related to sea ice. Model runs include changes in external forcings such as those from increasing greenhouse gases and aerosols. A consensus from the numerical modelling community is that greenhouse warming will be enhanced in the polar regions, especially the Arctic (Figure 8.1).