scholarly journals Timing of Little Ice Age maxima and subsequent glacier retreat in northern Troms and western Finnmark, northern Norway

2020 ◽  
Vol 52 (1) ◽  
pp. 281-311
Author(s):  
J. R. Leigh ◽  
C. R. Stokes ◽  
D. J. A. Evans ◽  
R. J. Carr ◽  
L. M. Andreassen
Keyword(s):  
Little Ice Age ◽  
Glacier Retreat ◽  
Ice Age ◽  
Northern Norway

Drastic glacier retreat at Pico de Orizaba (19º N, Mexico) since the Little Ice Age

2020 ◽  
Author(s):  
Jesús Alcalá Reygosa ◽  
Néstor Campos ◽  
Melaine Le Roy ◽  
Bijeesh Kozhikkodan Veettil ◽  
Adam Emmer
Keyword(s):  
Little Ice Age ◽  
Satellite Images ◽  
Physical Geography ◽  
Glacier Retreat ◽  
Ice Age ◽  
Glacier Area ◽  
Tropical Andes ◽  
Bolivian Andes ◽  
The Alps

<p>The Little Ice Age (LIA) occurred between CE 1250 and 1850 and is considered a period of moderate cold conditions, especially recorded in the northern hemisphere. Numerous recent studies provide robust evidence of glacier advances worldwide during the LIA and a dramatic retreat since then. These studies combined investigation of moraine records, paintings, topographical and glaciological measurements as well as multitemporal aerial and terrestrial photographs and satellite images. For instance, post-LIA glaciers retreat amounts ~60 % in the Alps (Paul et al., 2020), ~88 % in the Pyrenees (Rico et al., 2016) and 89 % in the Bolivian Andes (Ramírez et al., 2001). However, there is scarce knowledge in Mexico about the glacier changes since the LIA. The reconstructions are limited to the Iztaccíhualt volcano where Schneider et al. (2008) established a glacier retreat of 95 %.</p><p>Here, we reconstruct the glacier evolution since the LIA to CE 2015 of the Mexican highest ice-capped volcano: Pico de Orizaba (19° 01´ N, 97° 16´W, 5,675 m a.s.l.). Due to Pico de Orizaba is in the outer Tropic, the most plausible scenario is a glacier evolution similar to the Bolivian Andes and especially to the Iztaccíhualt volcano. To carry out this research, we mapped the glacier area during the LIA, based on moraine record, and the area during 1945, 1958, 1971, 1988, 1994, 2003 and 2015 using a previous map elaborated by Palacios and Vázquez-Selem (1996), aerial orthophotographs and satellite images. The geographical mapping and the calculus of area, minimum altitude and volume of the glacier were generated with the software ArcGIS 10.2.2. The results show that glacier area retreated 92% between the LIA (8.8 km<sup>2</sup>) and 2015 (0.67 km<sup>2</sup>), being a drastic glacier loss in agreement with the Bolivian Andes and Iztaccíhualt. Therefore, mexican glaciers have experienced the major shrunk since LIA that implies a highly sensitive reaction to global warming.</p><p>This research was supported by the Project UNAM-DGAPA-PAPIIT grant IA105318.</p><p>References</p><p>Palacios, D., Vázquez-Selem, L. 1996. Geomorphic effects of the retreat of Jamapa glacier, Pico de Orizaba volcano (Mexico). Geografiska Annaler, Series A, Physical Geography 78, 19-34.</p><p>Paul F., Rastner P., Azzoni R.S., Diolaiuti G., Fugazza D., Le Bris R., Nemec J., Rabatel A., Ramusovic M., Schwaizer G., and Smiraglia C. 2020. Glacier shrinkage in the Alps continues unabated as revealed by a new glacier inventory from Sentinel-2 https://doi.org/10.5194/essd-2019-213.</p><p>Ramírez, E., Francou, B., Ribstein, P., Descloitres, M., Guérin, R., Mendoza, J., Gallaire, R., Pouyaud, B., Jordan, E. 2001. Small glaciers disappearing in the tropical Andes: a case study in Bolivia: Glaciar Chacaltaya (16° S). Journal of Glaciology 47 (157), 187-194.</p><p>Rico I., Izagirre E., Serrano E., López-Moreno J.I., 2016. Current glacier area in the Pyrenees : an updated assessment 2016. Pirineos 172, doi: http://dx.doi.org/10.3989/Pirineos.2017.172004.</p><p>Schneider, D., Delgado-Granados, H., Huggel, C., Kääb, A. 2008. Assessing lahars from ice-capped volcanoes using ASTER satellite data, the SRTM DTM and two different flow models: case study on Iztaccíhuatl (Central Mexico). Natural Hazards and Earth System Sciences 8, 559-571.</p><p> </p><p> </p>

‘Little Ice Age’ maxima and glacier retreat in northern Troms and western Finnmark, northern Norway

2020 ◽  
Author(s):  
Joshua Leigh ◽  
Chris Stokes ◽  
David Evans ◽  
Rachel Carr ◽  
Liss Andreassen
Keyword(s):  
Little Ice Age ◽  
Ice Age ◽  
Early 20Th Century ◽  
Main Study ◽  
Remotely Sensed Data ◽  
Mountain Glacier ◽  
Northern Norway ◽  
Glacier Recession ◽  
Proglacial Lakes ◽  
Main Study Area

<p>Glaciers are important indicators of climate change and observations worldwide document increasing rates of mountain glacier recession. Here we present ~200 years of change in mountain glacier extent in northern Troms and western Finnmark. This was achieved through: (1) mapping recent (post-1980s) changes in ice extent from remotely sensed data and (2) lichenometric dating and mapping of major moraine systems within a sub-set of the main study area (the Rotsund Valley). Lichenometric dating reveals that the Little Ice Age (LIA) maximum occurred as early as AD 1814 (±41 years), which is before the early-20th century LIA maximum proposed on the nearby Lyngen Peninsula, but younger than the LIA maximum limits in southern and central Norway (ca. AD 1740-50). Between LIA maximum and AD 1989, the reconstructed glaciers (n = 15) shrank by 3.9 km<sup>2</sup> (39%), with those that shrank by >50% fronted by proglacial lakes. Between AD 1989 and 2018, the total area of glaciers within the study area (n = 219 in AD 1989) shrank by ~35 km<sup>2</sup>. Very small glaciers (<0.5 km<sup>2</sup> in AD 1989) show the highest relative rates of shrinkage, and 90% of mapped glaciers within the study area are <0.5 km<sup>2</sup> as of AD 2018.</p>

scholarly journals Widespread and accelerating glacier retreat on the Lyngen Peninsula, northern Norway, since their ‘Little Ice Age’ maximum

2018 ◽  
Vol 64 (243) ◽  
pp. 100-118 ◽  
Author(s):  
CHRIS R. STOKES ◽  
LISS M. ANDREASSEN ◽  
MATTHEW R. CHAMPION ◽  
GEOFFREY D. CORNER
Keyword(s):  
Little Ice Age ◽  
Winter Precipitation ◽  
Ice Age ◽  
Surface Hydrology ◽  
Northern Norway ◽  
Mountain Glaciers ◽  
Air Temperatures ◽  
Outburst Floods ◽  
Glacial Lake Outburst Floods ◽  
Global Sea Level

ABSTRACTThe recession of mountain glaciers worldwide is increasing global sea level and, in many regions, human activities will have to adapt to changes in surface hydrology. Thus, it is important to provide up-to-date analyses of glacier change and the factors modulating their response to climate warming. Here we report changes in the extent of >120 glaciers on the Lyngen Peninsula, northern Norway, where glacier runoff is utilised for hydropower and where glacial lake outburst floods have occurred. Glaciers covered at least 114 km2 in 1953 and we compare this inventory with those from 1988, 2001 and a new one from 2014, and previously-dated Little Ice Age (LIA) limits. Results show a steady reduction in area (~0.3% a−1) between their LIA maximum (~1915) and 1988, consistent with increasing summer air temperatures, but recession paused between 1988 and 2001, coinciding with increased winter precipitation. Air temperatures increased 0.5°C per decade from the 1990s and the rate of recession accelerated to ~1% a−1 between 2001 and 2014 when glacier area totalled ~95.7 km2. Small glaciers (<0.05 km2) with low maximum elevations (<1400 m) experienced the largest percentage losses and, if warming continues, several glaciers may disappear within the next two decades.

scholarly journals Little Ice Age glacial geomorphology and sedimentology of Portage Glacier, South-Central Alaska

Finisterra ◽  
2012 ◽  
Vol 44 (87) ◽  
Author(s):  
João Santos ◽  
Carlos Córdova
Keyword(s):  
Little Ice Age ◽  
Ice Sheets ◽  
Glacier Retreat ◽  
Ice Age ◽  
Glacial Geomorphology ◽  
South Central ◽  
Glacier Valley ◽  
Glacial Landforms ◽  
Basal Till ◽  
Insight Into

The study of glacial landforms and deposits is important, as it is difficult to observe processes under modern glaciers and ice-sheets. Thus landscapes and sediments that are the product of present glaciation can give insight into processes that occurred during  pleistocene times. This study investigates the genesis of little ice age glacial landforms present in portage Glacier, South-central Alaska. The present day moraine morphology and sedimentology in portage Glacier valley reveals the presence of two types of till and moraines. The clast-rich sandy diamicton present on the 1852 moraine is interpreted to be a basal till indicating this feature is a push moraine representing an advance or a standstill position of portage Glacier in 1852. The moderately sorted gray sandy boulder gravel present on the 1900 and 1922 moraines is interpreted to be an ice-marginal deposit (ablation till) with a mixture of supraglacial and glaciofluvial sediments deposited by slumping and stream sorting processes. All of these features are interpreted to be ablation moraines representing glacier retreat and moraine building in 1900 and1922.

An inverse approach to the course of the ‘Little Ice Age’ glacier advance and the following deglaciation at Austerdalsisen, eastern Svartisen, northern Norway

The Holocene ◽  
2018 ◽  
Vol 28 (7) ◽  
pp. 1041-1056 ◽  
Author(s):  
Henrik Løseth Jansen ◽  
Svein Olaf Dahl ◽  
Pål Ringkjøb Nielsen
Keyword(s):  
Little Ice Age ◽  
Ice Age ◽  
Outlet Glacier ◽  
Northern Norway ◽  
Inverse Approach ◽  
Ice Cap ◽  
Glacier Terminus ◽  
Outburst Floods ◽  
Valley Glacier ◽  
Glacier Advance

The course of the ‘Little Ice Age’ (LIA) in Scandinavia is characterized by large glacier advances that started at about AD 1300 and culminated at about AD 1750. The end of the LIA is marked as an unprecedented and ongoing glacier retreat that accelerated from the early 20th century. The course of the LIA is here presented based on fluctuations of Austerdalsisen, the largest valley outlet glacier draining the Austre Svartisen (Østisen) ice cap, Nordland, northern Norway. During the LIA glacierization, Austerdalsisen separated into two branches, and relative to the present glacier terminus, a western valley glacier advanced more than 4 km, whereas a SE valley glacier advanced about 3 km. At present, meltwater from Austerdalsisen drains towards SE. If the glacier obtains a critical magnitude, however, most of the meltwater is drained westwards across a higher overflow gap. Based on radiocarbon-dated lake sediments, distal proglacial glaciolacustrine/glaciofluvial sediments and historical observations, the course and chronology of the deglaciation following the LIA glacier maximum at Austerdalsisen are established. Because of high sedimentation rates due to low local bedrock resistance to glacier erosion beneath Austerdalsisen, however, cores from distal glacier-fed lakes covering the entire LIA/Holocene are hard to retrieve. Hence, an inverse approach to reconstruct the entire course of the LIA glacierization at Austerdalsisen is performed by suggesting little input of glacier-meltwater-induced sediments to the SE distal glacier-fed lake Litl Røvatnet, whenever Austerdalsisen rerouted meltwater westwards. If the terminus of Austerdalsisen was near the critical magnitude threshold, regular glacier lake outburst floods (GLOFs) towards SE occurred.

scholarly journals The Retreat of Mountain Glaciers since the Little Ice Age: A Spatially Explicit Database

Data ◽  
2021 ◽  
Vol 6 (10) ◽  
pp. 107
Author(s):  
Silvio Marta ◽  
Roberto Sergio Azzoni ◽  
Davide Fugazza ◽  
Levan Tielidze ◽  
Pritam Chand ◽  
...  
Keyword(s):  
Little Ice Age ◽  
Field Data ◽  
Satellite Images ◽  
Glacier Retreat ◽  
Ice Age ◽  
Spatially Explicit ◽  
Glacier Surface ◽  
Mountain Glaciers ◽  
The Past ◽  
Topographical Maps

Most of the world’s mountain glaciers have been retreating for more than a century in response to climate change. Glacier retreat is evident on all continents, and the rate of retreat has accelerated during recent decades. Accurate, spatially explicit information on the position of glacier margins over time is useful for analyzing patterns of glacier retreat and measuring reductions in glacier surface area. This information is also essential for evaluating how mountain ecosystems are evolving due to climate warming and the attendant glacier retreat. Here, we present a non-comprehensive spatially explicit dataset showing multiple positions of glacier fronts since the Little Ice Age (LIA) maxima, including many data from the pre-satellite era. The dataset is based on multiple historical archival records including topographical maps; repeated photographs, paintings, and aerial or satellite images with a supplement of geochronology; and own field data. We provide ESRI shapefiles showing 728 past positions of 94 glacier fronts from all continents, except Antarctica, covering the period between the Little Ice Age maxima and the present. On average, the time series span the past 190 years. From 2 to 46 past positions per glacier are depicted (on average: 7.8).

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