Mass balance modelling and climate sensitivity of Saskatchewan Glacier, western Canada

Abstract. Glacier mass balance models are needed at sites with scarce long-term observations to reconstruct past glacier mass balance and assess its sensitivity to future climate change. In this study North American Regional Reanalysis (NARR) data are used to force a physically-based, distributed glacier mass balance model of Saskatchewan Glacier for the historical period 1979–2016 and assess it sensitivity to climate change. A two-year record (2014–2016) from an on-glacier automatic weather station (AWS) and a homogenized historical precipitation record from nearby permanent weather stations were used to downscale air temperature, relative humidity, wind speed, incoming solar radiation and precipitation from the nearest NARR gridpoint to the glacier AWS site. The model was run with fixed (1979, 2010) and time-varying (dynamic) geometry using a multi-temporal digital elevation model (DEM) dataset. The model showed a good performance against recent (2012–2016) direct glaciological mass balance observations as well as with cumulative geodetic mass balance estimates. The simulated mass balance showed a large sensitivity to the biases in NARR precipitation and solar radiation, as well as to the prescribed precipitation lapse rate and ice aerodynamic roughness lengths, showing the importance of constraining these parameters with ancillary data. The difference between the static (1979) and dynamic simulations showed small differences (mean = 0.06 m w.e. a−1 or 1.5 m w.e. over 37 yrs), indicating minor effects of elevation changes on the glacier specific mass balance. The static mass balance sensitivity to climate was assessed for prescribed changes in regional mean air temperature between 0 to 7 °C and precipitation between −20 to +20 %, which comprise the spread of ensemble IPCC representative concentration pathways climate scenarios for the mid (2041–2070) and late (2071–2100) 21st century. The climate sensitivity experiments showed that future changes in precipitation would have a small impact on glacier mass-balance, while the temperature sensitivity increases with warming, from −0.65 to −0.93 m w.e. °C−1. Increased melting accounted for 90 % of the temperature sensitivity while precipitation phase feedbacks accounted for only 10 %. Roughly half of the melt response to warming was driven by a positive albedo feedback, in which glacier albedo decreases as the snow cover on the glacier thins and recedes earlier in response to warming, increasing net solar radiation fluxes. About one quarter of the melt response to warming was driven by latent heat energy gains (positive humidity feedback). Our study underlines the key role of albedo and air humidity in modulating the response of winter-accumulation type mountain glaciers and upland icefield-outlet glacier settings to climate.

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Derivation of melt factors from glacier mass-balance records in western Canada

Journal of Glaciology ◽

10.3189/002214309788608886 ◽

2009 ◽

Vol 55 (189) ◽

pp. 123-130 ◽

Cited By ~ 35

Author(s):

Joseph M. Shea ◽

R. Dan Moore ◽

Kerstin Stahl

Keyword(s):

Mass Balance ◽

Air Temperature ◽

Regional Scale ◽

Predictive Ability ◽

Lapse Rate ◽

Sensitivity Analyses ◽

Glacier Mass Balance ◽

Mean Values ◽

Ice Melt ◽

Standard Deviations

AbstractMelt factors for snow (ks) and ice (ki) were derived from specific mass-balance data and regionally interpolated daily air-temperature series at nine glaciers in the western Cordillera of Canada. Fitted ks and ki were relatively consistent across the region, with mean values (standard deviations) of 3.04 (0.38) and 4.59 (0.59) mm d−1 °C−1, respectively. The interannual variability of melt factors was investigated for two long-term datasets. Calculated annually, snow- and ice-melt factors were relatively stable from year to year; standard deviations for snowmelt factors were 0.48 (17%) and 0.42 (18%) at Peyto and Place Glaciers, respectively, while standard deviations of ice-melt factors were 1.17 (25%) and 0.81 (14%). While fitted values of ks are comparable to those presented in previous observational and modeling studies, fitted ki are substantially and consistently lower across the region. Fitted melt factors were sensitive to the choice of lapse rate used in the air-temperature interpolation. Melt factors fitted to mass-balance data from a single site (Place Glacier) provided reasonable summer balance predictions at most other sites representing both maritime and continental climates, although there was a tendency for under-prediction at several sites. The combination of regionally interpolated air temperatures and a degree-day model appears capable of generating first-order estimates of regional summer balance, which can provide a benchmark against which to judge the predictive ability of more complex (e.g. energy balance) models applied at a regional scale. Mass-balance sensitivity analyses indicate that a temperature increase of 1 K will increase summer ablation in the region by 0.51 m w.e. a−1 on average.

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Preliminary results of mass-balance observations of Yala Glacier and analysis of temperature and precipitation gradients in Langtang Valley, Nepal

Annals of Glaciology ◽

10.3189/2014aog66a106 ◽

2014 ◽

Vol 55 (66) ◽

pp. 9-14 ◽

Cited By ~ 22

Author(s):

Prashant Baral ◽

Rijan B. Kayastha ◽

Walter W. Immerzeel ◽

Niraj S. Pradhananga ◽

Bikas C. Bhattarai ◽

...

Keyword(s):

Climate Change ◽

Mass Balance ◽

Lapse Rate ◽

Convective Precipitation ◽

Glacier Mass Balance ◽

Equilibrium Line Altitude ◽

Temperature And Precipitation ◽

Meteorological Observations ◽

The Impact ◽

Langtang Valley

AbstractMonitoring the glacier mass balance of summer-accumulation-type Himalayan glaciers is critical to not only assess the impact of climate change on the volume of such glaciers but also predict the downstream water availability and the global sea-level change in future. To better understand the change in meteorological parameters related to glacier mass balance and runoff in a glacierized basin and to assess the highly heterogeneous glacier responses to climate change in the Nepal Himalaya and nearby ranges, the Cryosphere Monitoring Project (CMP) carries out meteorological observations in Langtang Valley and mass-balance measurements on Yala Glacier, a debris-free glacier in the same valley. A negative annual mass balance of –0.89m w.e. and the rising equilibrium-line altitude of Yala Glacier indicate a continuation of a secular trend toward more negative mass balances. Lower temperature lapse rate during the monsoon, the effect of convective precipitation associated with mesoscale thermal circulation in the local precipitation and the occurrence of distinct diurnal cycles of temperature and precipitation at different stations in the valley are other conclusions of this comprehensive scientific study initiated by CMP which aims to yield multi-year glaciological, hydrological and meteorological observations in the glacierized Langtang River basin.

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Modelling the impact of superimposed ice on the mass balance of an Arctic glacier under scenarios of future climate change

Annals of Glaciology ◽

10.3189/172756405781813104 ◽

2005 ◽

Vol 42 ◽

pp. 277-283 ◽

Cited By ~ 20

Author(s):

Andrew Wright ◽

Jemma Wadham ◽

Martin Siegert ◽

Adrian Luckman ◽

Jack Kohler

Keyword(s):

Climate Change ◽

Mass Balance ◽

Climate Model ◽

Global Climate Model ◽

Balance Model ◽

Explicit Calculation ◽

Future Climate Change ◽

Glacier Mass Balance ◽

Positive Contribution ◽

The Impact

AbstractA surface-energy/mass-balance model with an explicit calculation of meltwater refreezing and superimposed ice formation is applied to midre Lovénbreen, Spitsbergen, Svalbard. The model is run with meteorological measurements to represent the present climate, and run with scenarios taken from global climate model predictions based on the IS92a emissions scenario to represent future climates. Model results indicate that superimposed ice accounts for on average 37% of the total net accumulation under present conditions. The model is found to be highly sensitive to changes in the mean annual air temperature and much less sensitive to changes in the total annual precipitation. A 0.5˚C decade–1 temperature increase is predicted to cause an average mass-balance change of –0.43 ma–1, while a 2% decade–1 increase in precipitation will result in only a +0.02 ma–1 change in mass balance. An increase in temperature results in a significant decrease in the size of the accumulation area at midre Lovénbreen and hence a similar decrease in the net volume of superimposed ice. The model predicts, however, that the relative importance of superimposed ice will increase to account for >50% of the total accumulation by 2050. The results show that the refreezing of meltwater and in particular the formation of superimposed ice make an important positive contribution to the mass balance of midre Lovénbreen under present conditions and will play a vital future role in slowing down the response of glacier mass balance to climate change.

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Modelling glacier change in the Everest region, Nepal Himalaya

The Cryosphere ◽

10.5194/tc-9-1105-2015 ◽

2015 ◽

Vol 9 (3) ◽

pp. 1105-1128 ◽

Cited By ~ 89

Author(s):

J. M. Shea ◽

W. W. Immerzeel ◽

P. Wagnon ◽

C. Vincent ◽

S. Bajracharya

Keyword(s):

Climate Change ◽

Mass Balance ◽

Future Climate Change ◽

Glacier Mass Balance ◽

Glacier Change ◽

Nepal Himalaya ◽

Temperature And Precipitation ◽

Precipitation Anomalies ◽

Koshi Basin ◽

End Members

Abstract. In this study, we apply a glacier mass balance and ice redistribution model to examine the sensitivity of glaciers in the Everest region of Nepal to climate change. High-resolution temperature and precipitation fields derived from gridded station data, and bias-corrected with independent station observations, are used to drive the historical model from 1961 to 2007. The model is calibrated against geodetically derived estimates of net glacier mass change from 1992 to 2008, termini position of four large glaciers at the end of the calibration period, average velocities observed on selected debris-covered glaciers, and total glacierized area. We integrate field-based observations of glacier mass balance and ice thickness with remotely sensed observations of decadal glacier change to validate the model. Between 1961 and 2007, the mean modelled volume change over the Dudh Koshi basin is −6.4 ± 1.5 km3, a decrease of 15.6% from the original estimated ice volume in 1961. Modelled glacier area change between 1961 and 2007 is −101.0 ± 11.4 km2, a decrease of approximately 20% from the initial extent. The modelled glacier sensitivity to future climate change is high. Application of temperature and precipitation anomalies from warm/dry and wet/cold end-members of the CMIP5 RCP4.5 and RCP8.5 ensemble results in sustained mass loss from glaciers in the Everest region through the 21st century.

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Energy balance model of mass balance and its sensitivity to meteorological variability on Urumqi River Glacier No.1 in the Chinese Tien Shan

Scientific Reports ◽

10.1038/s41598-019-50398-4 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Yanjun Che ◽

Mingjun Zhang ◽

Zhongqin Li ◽

Yanqiang Wei ◽

Zhuotong Nan ◽

...

Keyword(s):

Climate Change ◽

Mass Balance ◽

Air Temperature ◽

Tien Shan ◽

Shortwave Radiation ◽

Balance Model ◽

Glacier Mass Balance ◽

Net Energy ◽

Glacier Surface ◽

Precipitation Seasonality

Abstract Energy exchanges between atmosphere and glacier surface control the net energy available for snow and ice melt. Based on the meteorological records in Urumqi River Glacier No.1 (URGN1) in the Chinese Tien Shan during the period of 2012–2015, an energy-mass balance model was run to assess the sensitivity of glacier mass balance to air temperature (T), precipitation (P), incoming shortwave radiation (Sin), relative humidity (RH), and wind speed (u) in the URGN1, respectively. The results showed that the glacier melting was mainly controlled by the net shortwave radiation. The glacier mass balance was very sensitivity to albedo for snow and the time scale determining how long the snow albedo approaches the albedo for firn after a snowfall. The net annual mass balance of URGN1 was decreased by 0.44 m w.e. when increased by 1 K in air temperature, while it was increased 0.30 m w.e. when decreased by 1 K. The net total mass balance increased by 0.55 m w.e. when increased precipitation by 10%, while it was decreased by 0.61 m w.e. when decreased precipitation by 10%. We also found that the change in glacier mass balance was non-linear when increased or decreased input condition of climate change. The sensitivity of mass balance to increase in Sin, u, and RH were at −0.015 m w.e.%−1, −0.020 m w.e.%−1, and −0.018 m w.e.%−1, respectively, while they were at 0.012 m w.e.%−1, 0.027 m w.e.%−1, and 0.017 m w.e.%−1 when decreasing in those conditions, respectively. In addition, the simulations of coupled perturbation for temperature and precipitation indicated that the precipitation needed to increase by 23% could justly compensate to the additional mass loss due to increase by 1 K in air temperature. We also found that the sensitivities of glacier mass balance in response to climate change were different in different mountain ranges, which were mainly resulted from the discrepancies in the ratio of snowfall to precipitation during the ablation season, the amount of melt energy during the ablation season, and precipitation seasonality in the different local regions.

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Reanalysing glacier mass balance measurement series

The Cryosphere ◽

10.5194/tc-7-1227-2013 ◽

2013 ◽

Vol 7 (4) ◽

pp. 1227-1245 ◽

Cited By ~ 128

Author(s):

M. Zemp ◽

E. Thibert ◽

M. Huss ◽

D. Stumm ◽

C. Rolstad Denby ◽

...

Keyword(s):

Climate Change ◽

Data Quality ◽

Mass Balance ◽

Sea Level ◽

Error Estimation ◽

Standard Procedure ◽

Systematic Errors ◽

Glacier Mass Balance ◽

Uncertainty Estimates ◽

Measurement Series

Abstract. Glacier-wide mass balance has been measured for more than sixty years and is widely used as an indicator of climate change and to assess the glacier contribution to runoff and sea level rise. Until recently, comprehensive uncertainty assessments have rarely been carried out and mass balance data have often been applied using rough error estimation or without consideration of errors. In this study, we propose a framework for reanalysing glacier mass balance series that includes conceptual and statistical toolsets for assessment of random and systematic errors, as well as for validation and calibration (if necessary) of the glaciological with the geodetic balance results. We demonstrate the usefulness and limitations of the proposed scheme, drawing on an analysis that comprises over 50 recording periods for a dozen glaciers, and we make recommendations to investigators and users of glacier mass balance data. Reanalysing glacier mass balance series needs to become a standard procedure for every monitoring programme to improve data quality, including reliable uncertainty estimates.

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Sensitivities of glacier mass balance and runoff to climate perturbations in Norway

Annals of Glaciology ◽

10.3189/2015aog70a004 ◽

2015 ◽

Vol 56 (70) ◽

pp. 79-88 ◽

Cited By ~ 16

Author(s):

Markus Engelhardt ◽

Thomas V. Schuler ◽

Liss M. Andreassen

Keyword(s):

Mass Balance ◽

Temperature Change ◽

Air Temperature ◽

Annual Runoff ◽

Precipitation Change ◽

Glacier Mass Balance ◽

Northern Norway ◽

Temperature Range ◽

Temperature And Precipitation ◽

Southern Norway

AbstractThis study evaluates sensitivities of glacier mass balance and runoff to both annual and monthly perturbations in air temperature and precipitation at four highly glacierized catchments: Engabreen in northern Norway and Ålfotbreen, Nigardsbreen and Storbreen, which are aligned along a west–east profile in southern Norway. The glacier mass-balance sensitivities to changes in annual air temperature range from 1.74 m w.e. K−1 for Ålfotbreen to 0.55 m w.e. K−1 for Storbreen, the most maritime and the most continental glaciers in this study, respectively. The runoff sensitivities of all catchments are 20–25% per degree temperature change and 6–18% for a 30% precipitation change. A seasonality of the sensitivities becomes apparent. With increasing continentality, the sensitivity of mass balance and runoff to temperature perturbations during summer increases, and the sensitivity of annual runoff to both temperature and precipitation perturbations is constricted towards changes during the ablation period. Comparing sensitivities in northern and southern Norway, as well as the variability across southern Norway, reveals that continentality influences sensitivities more than latitude does.

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Current and future occurrences of health-relevant, compound heat and ozone pollution events in six European ozone-temperature regions

10.5194/ems2021-61 ◽

2021 ◽

Author(s):

Sally Jahn ◽

Elke Hertig

Keyword(s):

Climate Change ◽

Air Temperature ◽

Large Scale ◽

Coupled Model ◽

Ground Level ◽

Future Climate Change ◽

Ozone Pollution ◽

Ground Level Ozone ◽

Ozone Concentrations ◽

Elevated Ozone

Air pollution and heat events present two major health risks, both already independently posing a significant threat to human health and life. High levels of ground-level ozone (O3) and air temperature often coincide due to the underlying physical relationships between both variables. The most severe health outcome is in general associated with the co-occurrence of both hazards (e.g. Hertig et al. 2020), since concurrent elevated levels of temperature and ozone concentrations represent a twofold exposure and can lead to a risk beyond the sum of the individual effects. Consequently, in the current contribution, a compound approach considering both hazards simultaneously as so-called ozone-temperature (o-t-)events is chosen by jointly analyzing elevated ground-level ozone concentrations and air temperature levels in Europe.Previous studies already point to the fact that the relationship of underlying synoptic and meteorological drivers with one or both of these health stressors as well as the correlation between both variables vary with the location of sites and seasons (e.g. Otero et al. 2016; Jahn, Hertig 2020). Therefore, a hierarchical clustering analysis is applied to objectively divide the study domain in regions of homogeneous, similar ground-level ozone and temperature characteristics (o-t-regions). Statistical models to assess the synoptic and large-scale meteorological mechanisms which represent main drivers of concurrent o-t-events are developed for each identified o-t-region.Compound elevated ozone concentration and air temperature events are expected to become more frequent due to climate change in many parts of Europe (e.g. Jahn, Hertig 2020; Hertig 2020). Statistical projections of potential frequency shifts of compound o-t-events until the end of the twenty-first century are assessed using the output of Earth System Models (ESMs) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6).Hertig, E. (2020) Health-relevant ground-level ozone and temperature events under future climate change using the example of Bavaria, Southern Germany. Air Qual. Atmos. Health. doi: 10.1007/s11869-020-00811-zHertig, E., Russo, A., Trigo, R. (2020) Heat and ozone pollution waves in Central and South Europe- characteristics, weather types, and association with mortality. Atmosphere. doi: 10.3390/atmos11121271Jahn, S., Hertig, E. (2020) Modeling and projecting health&#8208;relevant combined ozone and temperature events in present and future Central European climate. Air Qual. Atmos. Health. doi: 10.1007/s11869&#8208;020&#8208;009610Otero N., Sillmann J., Schnell J.L., Rust H.W., Butler T. (2016) Synoptic and meteorological drivers of extreme ozone concentrations over Europe. Environ Res Lett. doi: 10.1088/ 1748-9326/11/2/024005

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PROJECTION OF INCIDENT SURFACE SOLAR RADIATION IN CHINA UNDER A CLIMATE CHANGE SCENARIO

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w9-187-2019 ◽

2019 ◽

Vol XLII-3/W9 ◽

pp. 187-194

Author(s):

Y. K. Xiao ◽

Z. M. Ji ◽

C. S. Fu ◽

W. T. Du ◽

J. H. Yang ◽

...

Keyword(s):

Climate Change ◽

Solar Radiation ◽

21St Century ◽

Weighted Average ◽

Global Climate Models ◽

Future Climate Change ◽

The Tibetan Plateau ◽

Climate Change Scenarios ◽

Model Ensemble ◽

Surface Solar Radiation

Abstract. We projected incident surface solar radiation (SSR) over China in the middle (2040–2059) and end (2080–2099) of the 21st century in the Representative Concentration Pathway (RCP) 8.5 scenario using a multi-model ensemble derived from the weighted average of seven global climate models (GCMs). The multi-model ensemble captured the contemporary (1979–2005) spatial and temporal characteristics of SSR and reproduced the long-term temporal evolution of the mean annual SSR in China. However, it tended to overestimate values compared to observations due to the absence of aerosol effects in the simulations. The future changes in SSR showed increases over eastern and southern China, and decreases over the Tibetan Plateau (TP) and northwest China relative to the present day. At the end of the 21st century, there were SSR increases of 9–21 W m−2 over northwest, central, and south China, and decreases of 18–30 W m−2 over the TP in June–July–August (JJA). In northeast China, SSR showed seasonal variation with increases in JJA and decreases in December–January–February. The time series of annual SSR had a decreased linear trend for the TP, and a slightly increased trend for China during 2006–2099. The results of our study suggest that solar energy resources will likely decrease in the TP under future climate change scenarios.

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