scholarly journals Post-LIA glacier changes along a latitudinal transect in the Central Italian Alps

2014 ◽  
Vol 8 (6) ◽  
pp. 2235-2252 ◽  
Author(s):  
R. Scotti ◽  
F. Brardinoni ◽  
G. B. Crosta
Keyword(s):  
Atmospheric Temperature ◽  
Winter Precipitation ◽  
Ice Age ◽  
Glacier Change ◽  
Mass Balances ◽  
Italian Alps ◽  
Temperature Trends ◽  
Continental Divide ◽  
Latitudinal Transect ◽  
Order Of Magnitude

Abstract. The variability of glacier response to atmospheric temperature rise in different topo-climatic settings is still a matter of debate. To address this question in the Central Italian Alps, we compile a post-LIA (Little Ice Age) multitemporal glacier inventory (1860–1954–1990–2003–2007) along a latitudinal transect that originates north of the continental divide in the Livigno Mountains and extends south through the Disgrazia and Orobie ranges, encompassing continental-to-maritime climatic settings. In these sub-regions, we examine the area change of 111 glaciers. Overall, the total glacierized area has declined from 34.1 to 10.1 km2, with a substantial increase in the number of small glaciers due to fragmentation. The average annual decrease (AAD) in glacier area has risen by about 1 order of magnitude from 1860–1990 (Livigno: 0.45; Orobie: 0.42; and Disgrazia: 0.39 % a−1) to 1990–2007 (Livigno: 3.08; Orobie: 2.44; and Disgrazia: 2.27 % a−1). This ranking changes when considering glaciers smaller than 0.5 km2 only (i.e., we remove the confounding caused by large glaciers in Disgrazia), so that post-1990 AAD follows the latitudinal gradient and Orobie glaciers stand out (Livigno: 4.07; Disgrazia: 3.57; and Orobie: 2.47 % a−1). More recent (2007–2013) field-based mass balances in three selected small glaciers confirm post-1990 trends showing the consistently highest retreat in continental Livigno and minimal area loss in maritime Orobie, with Disgrazia displaying transitional behavior. We argue that the recent resilience of glaciers in Orobie is a consequence of their decoupling from synoptic atmospheric temperature trends, a decoupling that arises from the combination of local topographic configuration (i.e., deep, north-facing cirques) and high winter precipitation, which ensures high snow-avalanche supply, as well as high summer shading and sheltering. Our hypothesis is further supported by the lack of correlations between glacier change and glacier attributes in Orobie, as well as by the higher variability in ELA,sub>0 positioning, post-LIA glacier change, and interannual mass balances, as we move southward along the transect.

scholarly journals Post-LIA glacier changes along a latitudinal transect in the Central Italian Alps

2014 ◽  
Vol 8 (4) ◽  
pp. 4075-4126 ◽  
Author(s):  
R. Scotti ◽  
F. Brardinoni ◽  
G. B. Crosta
Keyword(s):  
Atmospheric Temperature ◽  
Winter Precipitation ◽  
Ice Age ◽  
Glacier Change ◽  
Mass Balances ◽  
Italian Alps ◽  
Temperature Trends ◽  
Continental Divide ◽  
Latitudinal Transect ◽  
Order Of Magnitude

Abstract. The variability of glacier response to atmospheric temperature rise in different topo-climatic settings is still matter of debate. To address this question in the Central Italian Alps we compile a post-LIA (Little Ice Age) multitemporal glacier inventory (1860-1954-1990-2003-2007) along a latitudinal transect that originates north of the continental divide in the Livigno mountains, and extends south through the Disgrazia and Orobie ranges, encompassing continental-to-maritime climatic settings. In these sub-regions we examine area change of 111 glaciers. Overall, total glacierized area has declined from 34.1 to 10.1 km2, with a substantial increase in the number of small glaciers due to fragmentation. Average annual decrease (AAD) in glacier area has risen of about an order of magnitude from 1860–1990 (Livigno: 0.45; Orobie: 0.42; and Disgrazia: 0.39 % a−1) to 1990–2007 (Livigno: 3.08; Orobie: 2.44; and Disgrazia: 2.27 % a−1). This ranking changes when considering glaciers <0.5 km2 only (i.e., we remove the confounding caused by large glaciers in Disgrazia), so that post-1990 AAD follows the latitudinal gradient and Orobie glaciers stand out (Livigno: 4.07; Disgrazia: 3.57; and Orobie: 2.47 % a−1). More recent (2007–2013) field-based mass balances in three selected small glaciers confirm post-1990 trends showing consistent highest retreat in continental Livigno and minimal area loss in maritime Orobie, with Disgrazia displaying a transitional behaviour. We argue that the recent resilience of glaciers in Orobie is a consequence of their decoupling from synoptic atmospheric temperature trends. A decoupling that arises from the combination of local topographic configuration (i.e., deep, north-facing cirques) and high winter precipitation, which ensures high snow-avalanche supply, as well as high summer shading and sheltering. Our hypothesis is further supported by the lack of correlations between glacier change and glacier attributes in Orobie, as well by the higher variability in ELA0 positioning, post-LIA glacier change, and inter-annual mass balances, as we move southward along the transect.

scholarly journals Fluctuations of a Greenlandic tidewater glacier driven by changes in atmospheric forcing: observations and modelling of Kangiata Nunaata Sermia, 1859–present

2014 ◽  
Vol 8 (6) ◽  
pp. 2031-2045 ◽  
Author(s):  
J. M. Lea ◽  
D. W. F. Mair ◽  
F. M. Nick ◽  
B. R. Rea ◽  
D. van As ◽  
...  
Keyword(s):  
Numerical Models ◽  
Atmospheric Temperature ◽  
Ice Age ◽  
Band Model ◽  
Glacier Change ◽  
Atmospheric Forcing ◽  
Climate Anomalies ◽  
Tidewater Glacier ◽  
Primary Driver ◽  
Oceanic Forcing

Abstract. Many tidewater glaciers in Greenland are known to have undergone significant retreat during the last century following their Little Ice Age maxima. Where it is possible to reconstruct glacier change over this period, they provide excellent records for comparison to climate records, as well as calibration/validation for numerical models. These glacier change records therefore allow for tests of numerical models that seek to simulate tidewater glacier behaviour over multi-decadal to centennial timescales. Here we present a detailed record of behaviour from Kangiata Nunaata Sermia (KNS), SW Greenland, between 1859 and 2012, and compare it against available oceanographic and atmospheric temperature data between 1871 and 2012. We also use these records to evaluate the ability of a well-established one-dimensional flow-band model to replicate behaviour for the observation period. The record of terminus change demonstrates that KNS has advanced/retreated in phase with atmosphere and ocean climate anomalies averaged over multi-annual to decadal timescales. Results from an ensemble of model runs demonstrate that observed dynamics can be replicated. Model runs that provide a reasonable match to observations always require a significant atmospheric forcing component, but do not necessarily require an oceanic forcing component. Although the importance of oceanic forcing cannot be discounted, these results demonstrate that changes in atmospheric forcing are likely to be a primary driver of the terminus fluctuations of KNS from 1859 to 2012. We propose that the detail and length of the record presented makes KNS an ideal site for model validation exercises investigating links between climate, calving rates, and tidewater glacier dynamics.

scholarly journals The mass balance of a cirque glacier in the Italian Alps (Ghiacciaio Della Sforzellina, Ortles–Cevedale Group)

1993 ◽  
Vol 39 (131) ◽  
pp. 87-90
Author(s):  
G. Catasta ◽  
C. Smiraglia
Keyword(s):  
Mass Balance ◽  
Mean Value ◽  
Climatic Conditions ◽  
Mass Balances ◽  
Italian Alps ◽  
Variation Data ◽  
Using Data

AbstractThe net mass balance (1986/87–1989/90) was calculated for a small cirque glacier in the Italian Alps (Ghiacciaio della Sforzellina, 0.42 k m2, Ortles–Cevedale Group). Four annual mass balances are presented here. All four balances were negative (mean value: –0.90 m year−1), with a maximum deficit of –1.16 m year−1 in 1989–90. The climatic conditions (which are analyzed using data from the S. Caterina Valfurva Station) consisted of a succession of cold, dry winters with little snowfall. Frontal-variation data available since 1925 show a constant retreat until 1966, followed by a brief advance period which has already terminated.

scholarly journals Recent fluctuations of glaciers in Valtellina (Italian Alps) and climatic variations

1992 ◽  
Vol 38 (129) ◽  
pp. 309-313 ◽  
Author(s):  
Manuela Pelfini ◽  
Claudio Smiraglia
Keyword(s):  
Temperature Fluctuations ◽  
Winter Precipitation ◽  
Meteorological Station ◽  
Summer Temperature ◽  
Italian Alps ◽  
Climatic Variations ◽  
Alpine Glaciers ◽  
The Mean

AbstractValtellina, located in the Italian Alps of Lombardy, is extensively glaciated. Since 1925, terminal variations of the glaciers have been recorded. By analysing a significant sample of valley glaciers, we have recognized a rapid retreat of the termini which occurred between 1925 and the early 1970s. A period of advance followed, which stopped in the second half of the 1980s. The mean summer-temperature fluctuations at the meteorological station of Sondrio at the centre of Valtellina, show that the period 1925–52 was very warm, and then the temperatures dropped. The most intense winter precipitation occurred in the period 1925–37. The behaviour of these glaciers is similar to that of other Alpine glaciers, although time of response may be different.

scholarly journals Climate reconstruction since the Little Ice Age by modelling Koryto glacier, Kamchatka Peninsula, Russia

2008 ◽  
Vol 54 (184) ◽  
pp. 125-130 ◽  
Author(s):  
Satoru Yamaguchi ◽  
Renji Naruse ◽  
Takayuki Shiraiwa
Keyword(s):  
20Th Century ◽  
Meteorological Data ◽  
Ice Core ◽  
Kamchatka Peninsula ◽  
Winter Precipitation ◽  
Ice Age ◽  
Equilibrium Line Altitude ◽  
Ice Cap ◽  
Glacier Terminus ◽  
Tree Ring Data

AbstractBased on the field data at Koryto glacier, Kamchatka Peninsula, Russia, we constructed a one-dimensional numerical glacier model which fits the behaviour of the glacier. The analysis of meteorological data from the nearby station suggests that the recent rapid retreat of the glacier since the mid-20th century is likely to be due to a decrease in winter precipitation. Using the geographical data of the glacier terminus variations from 1711 to 1930, we reconstructed the fluctuation in the equilibrium-line altitude by means of the glacier model. With summer temperatures inferred from tree-ring data, the model suggests that the winter precipitation from the mid-19th to the early 20th century was about 10% less than that at present. This trend is close to consistent with ice-core results from the nearby ice cap in the central Kamchatka Peninsula.

scholarly journals Historical Variations of Lemon Creek Glacier, Alaska, and Their Relationship to the Climatic Record

1964 ◽  
Vol 5 (37) ◽  
pp. 77-86 ◽  
Author(s):  
Calvin J. Heusser ◽  
Melvin G. Marcus
Keyword(s):  
Field Research ◽  
Focus Of Attention ◽  
Ice Age ◽  
Research Project ◽  
Related Research ◽  
Olympic Mountains ◽  
Temperature Trends ◽  
Ice Field ◽  
Climatic Record ◽  
Last Ice Age

AbstractLemon Creek Glacier served as the focus of attention of the Juneau Ice Field Research Project from 1953 through 1958, during which period glaciological and related research was accomplished. This paper provides an historical framework for those studies by (1) considering variations of Lemon Creek Glacier in recent centuries and during millennia since the last ice age, and (2) describing certain relationships which appear to exist between these variations and the climatic record.It is found that Lemon Creek Glacier has been receding intermittently since a maximumc. 1750 and by 1958 had lostc. 25 per cent of the former area. Most rapid recession occurred during the periods 1891–1902 and 1929–58. Behaviour of the glacier sincec. 1750 reveals a parallelism with glaciers in most of the regions where temperature trends have been graphed as well as with other glaciers of the Juneau Ice Field. The advances of the 1950’s observed in the Rocky, Cascade and Olympic Mountains do not, however, show up in the Juneau area. Lemon Creek Glacier has not advanced more than 375 m. beyond the 1750 position, if at all, during the last 10,000 yr.

scholarly journals The geodetic mass balance of Eyjafjallajökull ice cap for 1945–2014: processing guidelines and relation to climate

2019 ◽  
Vol 65 (251) ◽  
pp. 395-409 ◽  
Author(s):  
JOAQUÍN M. C. BELART ◽  
EYJÓLFUR MAGNÚSSON ◽  
ETIENNE BERTHIER ◽  
FINNUR PÁLSSON ◽  
GUðFINNA AÐALGEIRSDÓTTIR ◽  
...  
Keyword(s):  
Mass Balance ◽  
Robust Statistics ◽  
Winter Precipitation ◽  
Summer Temperature ◽  
Aerial Photographs ◽  
Mass Balances ◽  
Stereo Images ◽  
Surface Mass ◽  
Ice Cap ◽  
Static Sensitivity

ABSTRACTMass-balance measurements of Icelandic glaciers are sparse through the 20th century. However, the large archive of stereo images available allows estimates of glacier-wide mass balance ($\dot{B}$) in decadal time steps since 1945. Combined with climate records, they provide further insight into glacier–climate relationship. This study presents a workflow to process aerial photographs (1945–1995), spy satellite imagery (1977–1980) and modern satellite stereo images (since 2000) using photogrammetric techniques and robust statistics in a highly automated, open-source pipeline to retrieve seasonally corrected, decadal glacier-wide geodetic mass balances. In our test area, Eyjafjallajökull (S-Iceland, ~70 km2), we obtain a mass balance of $<![CDATA[ $ \dot{\curr B}_{\curr 1945}^{\curr 2014} \curr = -0.27 \pm 0.03\,{\rm \curr m\ w}{\rm. \curr e}{\rm.} {\rm \curr a}^{{\rm \ndash \curr 1}}$, with a maximum and minimum of $\dot{\curr B}_{\curr 1984}^{\curr 1989} \curr = 0.77 \curr \pm 0.19\,{\rm \curr m\ \curr w}{\rm\curr . e}{\rm\curr .} {\rm\curr a}^{{\rm\curr \ndash 1}}$ and $\dot{\curr B}_{\curr 1994}^{\curr 1998}\curr = -1.94 \curr \pm 0.34\,{\rm \curr m\ w}{\rm\curr . e}{\rm\curr .} {\rm \curr a}^{{\rm\curr \ndash 1}}$, respectively, attributed to climatic forcing, and $\dot{\curr B}_{\curr 2009}^{\curr 2010} \curr = -3.39{\rm \;} \curr \pm {\rm \;} \curr 0.43\,{\rm \curr m\ w}{\rm\curr . e}{\rm\curr .} {\rm\curr a}^{{\rm\curr \ndash 1}}$, mostly caused by the April 2010 eruption. The reference-surface mass balances correlate with summer temperature and winter precipitation, and linear regression accounts for 80% of the mass-balance variability, yielding a static sensitivity of mass balance to summer temperature and winter precipitation of − 2.1 ± 0.4 m w.e.a–1K–1 and 0.5 ± 0.3 m w.e.a–1 (10%)–1, respectively. This study serves as a template that can be used to estimate the mass-balance changes and glaciers' response to climate.

A millennium-length temperature reconstruction for the eastern Mediterranean

2020 ◽  
Author(s):  
Jan Esper ◽  
Lara Klippel ◽  
Paul J. Krusic ◽  
Oliver Konter ◽  
Christoph Raible ◽  
...  
Keyword(s):  
Central Europe ◽  
Climate Model ◽  
Eastern Mediterranean ◽  
Temperature Reconstruction ◽  
Ice Age ◽  
Temperature Trends ◽  
Latewood Density ◽  
Scale Temperature ◽  
The Mediterranean ◽  
Millennial Scale

&lt;p&gt;The Mediterranean has been identified as particularly vulnerable to climate change, yet a high-resolution temperature reconstruction extending back into the Medieval Warm Period is still lacking. Here we present such a record from a high-elevation site on Mt. Smolikas in northern Greece, where some of Europe&amp;#8217;s oldest trees provide evidence of warm season temperature variability back to 730 CE. The reconstruction is derived from 192 annually resolved, latewood density series from ancient living and relict Pinus heldreichii trees calibrating at r&lt;sub&gt;1911-2015&lt;/sub&gt; = 0.73 against regional July-September (JAS) temperatures. Although the recent 1985-2014 period was the warmest 30-year interval (JAS T&lt;sub&gt;wrt.1961-90&lt;/sub&gt; = +0.71&amp;#176;C) since the 11&lt;sup&gt;th&lt;/sup&gt; century, temperatures during the 9-10&lt;sup&gt;th&lt;/sup&gt; centuries were even warmer, including the warmest reconstructed 30-year period from 876-905 (+0.78&amp;#176;C). These differences between warm periods are statistically insignificant though. Several distinct cold episodes punctuate the Little Ice Age, albeit the coldest 30-year period is centered during high medieval times from 997-1026 (-1.63&amp;#176;C). Comparison with reconstructions from the Alps and Scandinavia shows that a similar cold episode occurred in central Europe but was absent at northern latitudes. The reconstructions also reveal different millennial-scale temperature trends (NEur = -0.73&amp;#176;C/1000 years, CEur = -0.13 &amp;#176;C, SEur = +0.23&amp;#176;C) potentially triggered by latitudinal changes in summer insolation due to orbital forcing. These features, the opposing millennial-scale temperature trends and the medieval multi-decadal cooling recorded in Central Europe and the Mediterranean, are not well captured in state-of-the-art climate model simulations.&lt;/p&gt;

scholarly journals Glaciers and Climate in Svalbard: Statistical Analysis and Reconstruction of the Brøggerbreen Mass Balance for the Last 77 Years

1990 ◽  
Vol 14 ◽  
pp. 148-152 ◽  
Author(s):  
B. Lefauconnier ◽  
J.O. Hagen
Keyword(s):  
Mass Balance ◽  
Winter Precipitation ◽  
Multiple Correlation Coefficient ◽  
Wave Radiation ◽  
Mass Balances ◽  
Multiple Correlation ◽  
Long Wave ◽  
Summer Temperatures ◽  
Balance Deficit ◽  
Good Agreement

The long series of mass-balance data obtained by the Norsk Polarinstitutt on Brøggerbreen for the period 1967–88 has been correlated to climatological parameters from the meteorological station in Ny-Ålesund. The best multiple correlation coefficient was obtained between mass balance and positive summer and autumn temperatures combined with winter precipitations, for which R = 0.90. The regression equation gives a very good agreement between observed and estimated mass balance for Brøggerbreen. A test for 8 years which includes summer long-wave radiation, gives a coefficient of R = 0.98. Based on the good correlation between temperatures at several stations, we reconstructed summer temperatures in Longyearbyen and Brøggerbreen mass balances for 1912–88. The end of the cold period before 1918 is connected with historical observations of the maximum advance of cirque glaciers. After an increase between 1912 and 1920, summer and autumn temperatures decreased slowly. From 1920 this decay has been of −0.7°C. Mass balance has been negative since 1918, and the total mass lost at Brøggerbreen is 34.35 m of water equivalent. For the period with available data in Ny-Ålesund (1969–88), a very slight cooling during the ablation period and an increase in winter precipitation has maintained the reduction of the net balance deficit.

Tree-ring-based mass-balance estimates for the past 300 years at Peyto Glacier, Alberta, Canada

2004 ◽  
Vol 62 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Emma Watson ◽  
Brian H Luckman
Keyword(s):  
Mass Balance ◽  
Tree Ring ◽  
Gulf Of Alaska ◽  
Winter Precipitation ◽  
Canadian Rocky Mountains ◽  
Mass Balances ◽  
Positive Mass ◽  
Canadian Rockies ◽  
Temperature And Precipitation ◽  
Tree Ring Data

Tree rings were used to reconstruct mass balance for Peyto Glacier in the Canadian Rocky Mountains from A.D. 1673 to 1994. Summer balance was reconstructed from tree-ring estimates of summer temperature and precipitation in the Canadian Rockies. Winter balance was derived from tree-ring data from sites bordering the Gulf of Alaska and in western British Columbia. The models for winter and summer balance each explain over 40% of the variance in the appropriate mass-balance series. Over the period 1966–1994 the correlation between the reconstructed and measured net balances is 0.71. Strong positive mass balances are reconstructed for 1695–1720 and 1810–1825, when higher winter precipitation coincided with reduced ablation. Periods of reconstructed positive mass balance precede construction of terminal moraines throughout the Canadian Rockies ca. 1700–1725 and 1825–1850. Positive mass balances in the period 1845–1880 also correspond to intervals of glacier readvance. Mass balances were generally negative between 1760 and 1805. From 1673 to 1883 the mean annual net balance was +70 mm water equivalent per year (w.e./yr.), but it averaged −317 mm w.e./yr from 1884 to 1994. This reconstructed mass balance history provides a continuous record of glacier change that appears regionally representative and consistent with moraine and other proxy climate records.

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