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Modern Regression


In statistics, regression analysis includes any techniques for modelling and analyzing several variables, when the focus is on the relationship between a dependent variable and one or more independent variables. More specifically, regression analysis helps us understand how the typical value of the dependent variable changes when any one of the independent variables is varied, while the other independent variables are held fixed.

 
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Assessing Spatio-temporal Variability and Trends in Modelled and M...

By: X. Fettweis; R. S. W. Van De Wal; M. Tedesco; M. R. Van Den Broeke; C. J. P. P. Smeets; P. M. Alexander

Description: Graduate Center of the City University of New York, 365 5th Ave., New York, NY, 10016 USA. Accurate measurements and simulations of Greenland Ice Sheet (GrIS) surface albedo are essential, given the role of surface albedo in modulating the amount of absorbed solar radiation and meltwater production. In this study, we assess the spatio-temporal variability of GrIS albedo during June, July, and August (JJA) for the period 2000–2013. We use two remote sensi...

Bamber, J. L., Ekholm, S., and Krabill, W. B.: A new, high-resolution digital elevation model of Greenland fully validated with airborne laser altimeter data, J. Geophys. Res., 106, 6733–6745, 2001.; Bamber, J. L., Griggs, J. A., Hurkmans, R. T. W. L., Dowdeswell, J. A., Gogineni, S. P., Howat, I., Mouginot, J., Paden, J., Palmer, S., Rignot, E., and Steinhage, D.: A new bed elevation dataset for Greenland, The Cryosphere, 7, 499–510,

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Solving Richards Equation for Snow Improves Snowpack Meltwater Run...

By: H. Hirashima; C. Mitterer; C. Fierz; N. Wever; M. Lehning

Description: WSL Institute for Snow and Avalanche Research SLF, Flüelastrasse 11, 7260 Davos Dorf, Switzerland. The runoff from a snow cover during spring snowmelt or rain-on-snow events is an important factor in the hydrological cycle. In this study, three water balance schemes for the 1 dimensional physically-based snowpack model SNOWPACK are compared to lysimeter measurements at two alpine sites with a seasonal snow cover, but with different climatological conditi...

Kattelmann, R.: Macropores in snowpacks of Sierra Nevada, Ann. Glaciol., 6, 272–273, 1985.; Bartelt, P. and Lehning, M.: A physical SNOWPACK model for the Swiss avalanche warning Part I: Numerical model, Cold Reg. Sci. Technol., 35, 123–145, doi:10.1016/S0165-232X(02)00074-5, 2002.; Baunach, T., Fierz, C., Satyawali, P. K., and Schneebeli, M.: A model for kinetic grain growth, Ann. Glaciol., 32, 1–6,

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Surge Dynamics in the Nathorstbreen Glacier System, Svalbard : Vol...

By: T. R. Lauknes; T. Eiken; M. Sund

Description: Hydrology department, Norwegian Water Resources and Energy Directorate, P.O. Box 5091 Majorstuen 0301 Oslo, Norway. Nathorstbreen glacier system (NGS) recently experienced the largest surge in Svalbard since 1936, and this was examined using spatial and temporal observations from DEM differencing, time series of surface velocities from satellite synthetic aperture radar (SAR) and other sources. The upper basins with maximum accumulation during quiescence...

Bartholomaus, T. C., Anderson, R., and Anderson, S. P.: Response of glacier basal motion to transient water storage, Nat. Geosci., 1, 33–37, 2008.; Björnsson, H., Gjessing, Y., Hamran, S. -E., Hagen, J. O., Liestøl, O., Pálsson, O., and Erlingsson, B.: The thermal regime of sub-polar glaciers mapped by multi-frequency radio-echo sounding, J. Glaciol., 42, 23–32, 1996.; Budd, W. F.: A first simple model for periodically self-surging glaciers, J. Glaciol., 14, 3–21, 1975.;...

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Drifting Snow Measurements on the Greenland Ice Sheet and Their Ap...

By: W. Boot; W. J. Van De Berg; J. T. M. Lenaerts; M. R. Van Den Broeke; M. Eijkelboom; C. J. P. P. Smeets; K. Nishimura

Description: Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, the Netherlands. This paper presents autonomous drifting snow observations performed on the Greenland Ice Sheet in the fall of 2012. High-frequency snow particle counter (SPC) observations at ~ 1 m above the surface provided drifting snow number fluxes and size distributions; these were combined with meteorological observations at six levels. We identify two types of drif...

Bintanja, R.: Snowdrift suspension and atmospheric turbulence, Part 1: Theoretical background and model description, Bound.-Lay. Meteorol., 95, 343–368, 2000.; Budd, W. F., Dingle, W. R. J., and Radok, U.: The B}yrd Snowdrift Project: Outline and Basic Results, vol. 9 of {Antarctic research series, AGU, 1966.; Bougamont, M., Bamber, J. L., and Greuell, W.: A surface mass balance model for the Greenland Ice Sheet, J. Geophys. Res., 110, F04018,

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Verification of Analysed and Forecasted Winter Precipitation in Co...

By: M. Schirmer; B. Jamieson

Description: Department of Civil Engineering, University of Calgary, Calgary, AB, Canada. Numerical Weather Prediction (NWP) models are rarely verified for mountainous regions during the winter season, although avalanche forecasters and other decision makers frequently rely on NWP models. Winter precipitation from two NWP models (GEM-LAM and GEM15) and from a precipitation analysis system (CaPA) was verified at approximately 100 stations in the mountains of western ...

Mahfouf, J.-F., Brasnett, B., and Gagnon, S.: A Canadian precipitation analysis (CaPA) project: Description and preliminary results, Atmos.-Ocean, 45, 1–17, 2007.; Bélair, S., Roch, M., Leduc, A.-M., Vaillancourt, P. A., Laroche, S., and Mailhot, J.: Medium-range quantitative precipitation forecasts from Canada's new 33-km deterministic global operational system, Weather Forecast., 24, 690–708, 2009.; Bellaire, S. and Jamieson, B.: Forecasting the formation of critical s...

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Mass Changes of Southern and Northern Inylchek Glacier, Central Ti...

By: Y. J. Ding; H. U. Wetzel; M. Kröhnert; S. Y. Liu; T. Pieczonka; D. H. Shangguan; T. Bolch

Description: State Key Laboratory of Cryospheric Science, Cold & Arid Regions Environmental & Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China. Glacier melt is an essential source of freshwater for the arid regions surrounding the Tian Shan. However, the knowledge about glacier volume and mass changes over the last decades is limited. In the present study, glacier area, glacier dynamics and mass changes are investigated for the period...

Aizen, V. B., Aizen, E., Dozier, J., and Melack, J. M.: Glacier regime of the highest Tien Shan mountain, Pobeda-Khan Tengry Massif, J. Glaciol., 43, 503–512, 1997.; Aizen, V. B., Kuzmichenok, V. A., Surazakov, A. B., and Aizen, E. M.: Glacier changes in the central and northern Tien Shan during the last 140 years based on surface and remote-sensing data, Ann. Glaciol., 43, 202–213, 2006.; Aizen, V. B., Aizen, E. M., and Kuzmichonok, V. A.: Glaciers and hydrological chan...

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Reconstruction of the 1979–2006 Greenland Ice Sheet Surface Mass B...

By: X. Fettweis

Description: Institut d'Astronomie et de Géophysique Georges Lemaître, Université catholique de Louvain, Louvain-la-Neuve, Belgium. Results from a 28-year simulation (1979–2006) over the Greenland ice sheet (GIS) reveal an increase of the solid precipitation (+0.4±2.5 km3 yr−2) and the run-off (+7.9±3.3 km3 yr−2) of surface melt water. The net effect of these competing factors leads to a significant Surface Mass Balance (SMB...

Box, J. E., Bromwich, D. H., and Bai, L.-S.:Greenland ice sheet surface mass balance for 1991–2000: application of Polar MM5 mesoscale model and in-situ data, J. Geophys. Res., 109(D16), D16105, doi:10.1029/2003JD004451, 2004.; Box, J. E., Bromwich, D. H., Veenhuis, B. A., Bai, L.-S., Stroeve, J. C., Rogers, J. C., Steffen, K., Haran, T., and Wang, S.-H.: Greenland ice sheet surface mass balance variability (1988–2004) from calibrated Polar MM5 output, J. Climate, 19(12)...

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On the Limit to Resolution and Information on Basal Properties Obt...

By: M. Raymond; G. H. Gudmundsson

Description: British Antarctic Survey, High Cross, Madingley Rd., Cambridge CB3 0ET, UK. An optimal estimation method for simultaneously determining both basal slipperiness and basal topography from variations in surface flow velocity and topography along a flow line on ice streams and ice sheets is presented. We use Bayesian inference to update prior statistical estimates for basal topography and slipperiness using surface measurements along a flow line. The method...

Arthern, R J. and Hindmarsh, R. C A.: Optimal estimation of changes in the mass of ice sheets, J. Geophys. Res., 108, \doi10.1029/2003JF000021, 2003.; Box, G., Jenkins, G M., and Reinsel, G.: Time Series Analysis: Forecasting and Control, Prentice Hall, 3rd edition edn., 1994. %; ; Gudmundsson, G H.: Transmission of basal variability to a glacier surface, J. Geophys. Res., 108(B5), 2253, doi:10.1029/2002JB002107, 2003.; Gudmundsson, G H.: Glaciers and earth's changing en...

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Melting Trends Over the Greenland Ice Sheet (1958-2009) from Space...

By: M. Tedesco; M. Van Den Broeke; X. Fettweis; J. Ettema

Description: Département de Géographie, Université de Liège, Liège, Belgium. To study near-surface melt changes over the Greenland ice sheet (GrIS) since 1979, melt extent estimates from two regional climate models are compared with those obtained from spaceborne microwave brightness temperatures using two different remote sensing algorithms. Results from the two models are consistent with those obtained with the remote sensing algorithms, at both daily and yearly t...

Abdalati, W. and Steffen, K.: Snowmelt on the Greenland ice sheet as derived from passive microwave satellite data, J. Clim., 10, 165–175, 1997.; Abdalati, W. and Steffen, K.: Greenland ice sheet melt extent: 1979–1999, J. Geophys. Res., 106, 33983–33988, 2001.; Abdalati W., Steffen, K., Otto, C., and Jezek, K. C.: Comparison of brightness temperatures from SSMI instruments on the DMSP F8 and FII satellites for Antarctica and the Greenland ice sheet, Int. J. Remote Sens....

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Climate of the Greenland Ice Sheet Using a High-resolution Climate...

By: W. J. Van De Berg; M. R. Van Den Broeke; E. Van Meijgaard; J. Ettema

Description: Institute for Marine and Atmospheric research Utrecht, Utrecht University, Utrecht, The Netherlands. The near-surface climate of the Greenland ice sheet is characterized by persistent katabatic winds and quasi-permanent temperature deficit. Using a high resolution (11 km) regional climate model allows for detailed study of the spatial variability in these phenomena and the underlying atmospheric processes.

The near-surface temperature distribu...

Ambach, W.: Untersuchungen zum E}nergieumsatz in der {A}blationszone des {G}r{ö}nl{ä}ndischen {I}nlandeises, Expedition Glaciologique Internationale au Groenland, 4, 63, {Bianco Lunos Bogtrykkeri A/S, Kopenhagen, 1977{a}.; Box, J. E. and Steffen, K.: Sublimation on the {G}reenland ice sheet from automated weather station observations, J. Geophys. Res., 106, 33965–33981, 2001.; Ambach, W.: Untersuchungen zum E}nergieumsatz in der {A}kkumulationszone des {G}r{ö}nl{ä}ndisch...

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Application of a Minimal Glacier Model to Hansbreen, Spitsbergen :...

By: L. Kolondra; J. Jania; J. Oerlemans

Description: Institute for Marine and Atmospheric research Utrecht, Utrecht University, P.O. Box 80005, 3508 TA Utrecht, The Netherlands. Hansbreen is a well studied tidewater glacier in the southwestern part of Spitsbergen, currently about 16 km long. Since the end of the 19th century it has been retreating over a distance of 2.7 km. In this paper the global dynamics of Hansbreen are studied with a minimal glacier model, in which the ice mechanics are st...

Baeten N., Forwick M., and Vorren T.: Glacial activity and sedimentary processes in Billefjorden, Spitsbergen – preliminary results, 37th International Arctic Workshop, Program and Abstracts, Skaftafell, Iceland, May 2–4, 2007, The Earth Science Institute, University of Iceland, Reykjavik, 41–42, 2007.; Benn, D. I., Hulton, N. R. J., and Mottram, R. H.: Calving laws, sliding laws and the stability of tidewater glaciers, Ann. Glaciol., 46, 123–130, 2007.; Birkenmejer, K. ...

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Sensitivity of Greenland Ice Sheet Surface Mass Balance to Surface...

By: J. H. Van Angelen; X. Fettweis; E. Van Meijgaard; S. Lhermitte; P. Kuipers Munneke; J. T. M. Lenaerts; M. R. Van Den Broeke

Description: Institute for Marine and Atmospheric Research Utrecht, Utrecht University, The Netherlands. We present a sensitivity study of the surface mass balance (SMB) of the Greenland Ice Sheet, as modeled using a regional atmospheric climate model, to various parameter settings in the albedo parameterization. The snow albedo parameterization uses grain size as a prognostic variable and further depends on cloud cover, solar zenith angle and black carbon concentr...

Abdalati, W. and Steffen, K.: Snowmelt on the Greenland ice sheet as derived from passive microwave satellite data, J. Climate, 10, 165–175, doi:10.1175/1520-0442(1997)010{\textless0165:SOTGIS{\textgreater}2.0.CO;2}, 1997.; Abdalati, W. and Steffen, K.: Greenland ice sheet melt extent: 1979–1999, J. Geophys. Res., 106, 33983–33988, doi:10.1029/2001JD900181, 2001.; ...

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A Method for Sea Ice Thickness and Concentration Analysis Based on...

By: M. Arkett; B. Cheng; T. Vihma; J. Karvonen; T. Carrieres

Description: Finnish Meteorological Institute (FMI), Helsinki, PB 503, 00101, Finland. An analysis of ice thickness distribution is a challenge, particularly in a seasonal sea ice zone with strongly dynamic ice motion field, such as the Gulf of St. Lawrence off Canada. We present a method for ice concentration and thickness analysis combining modelling of sea ice thermodynamics and detection of ice motion on the basis of space-borne Synthetic Aperture...

Astola, J., Haavisto, P., and Neuvo, Y.: Vector median filters, P. IEEE, 78, 678–689, 1990.; Andersen, S., Tonboe, R., Kaleschke, L., and Heygster, G.: Intercomparison of passive microwave sea ice concentration retrievals over the high-concentration Arctic sea ice, J. Geophys. Res., 112, C08004, doi:10.1029/2006JC003543, 2007.; Biazzi, B., Alparone, L., Baronti, S., and Borri, G.: Pyramid-based multi-resolution adaptive ...

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Future Projections of the Greenland Ice Sheet Energy Balance Drivi...

By: M. Erpicum; X. Fettweis; B. Franco

Description: DÉpartement de GÉographie, UniversitÉ de LiÈge, LiÈge, Belgium. In this study, 25 km-simulations are performed over the Greenland ice sheet (GrIS) throughout the 20th and 21st centuries, using the regional climate model MAR forced by four RCP scenarios from two CMIP5 global circulation models, in order to investigate the projected changes of the surface energy balance (SEB) components driving the surface melt. Analysis of 2000–2100 melt anoma...

Bamber, J. L., Layberry, R. L., and Gogineni, S. P.: A new ice thickness and bed data set for the Greenland ice sheet 1. Measurement, data reduction, and errors, J. Geophys. Res., 106, 33773–33780, 2001.; Belleflamme, A., Fettweis, X., Lang, C., and Erpicum, M.: Current and future atmospheric circulation at 500 hPa over Greenland simulated by the CMIP3 and CMIP5 global models, Clim. Dynam., submitted, 2012.; Box, J. E. and Cohen, A. E.: Upper-air temperatures around Gree...

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Analysis of the Snow-atmosphere Energy Balance During Wet-snow Ins...

By: C. Mitterer; J. Schweizer

Description: WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland. Wet-snow avalanches are notoriously difficult to predict, as their formation mechanism is poorly understood and in-situ measurements closely related to instability are inexistent. Instead, air temperature is commonly used as predictor variable for days with high wet-snow avalanche danger – with limited success. As melt water is a major driver of wet-snow instability and snow me...

Breiman, L., Friedman, J. H., Olshen, R. A., and Stone, C. J.: Classification and regression trees, CRC Press, Boca Raton, USA, 368 pp., 1998.; Brun, E. and Rey, C.: Field study on snow mechanical properties with special regard to liquid water content, IAHS-AISH P., 162, 183–193, 1987.; Arck, M. and Scherer, D.: Problems in the determination of sensible heat flux over snow, Geogr. Ann. A, 84A, 157–169, 2002.; Baggi, S. and Schweizer, J.: Characteristics of wet snow avala...

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Estimating Greenland Ice Sheet Surface Mass Balance Contribution t...

By: M. Tedesco; B. Franco; J. H. Van Angelen; X. Fettweis; J. T. M. Lenaerts; H. Gallée; M. R. Van Den Broeke

Description: Department of Geography, University of Liège, Belgium. We report future projections of Surface Mass Balance (SMB) over the Greenland ice sheet (GrIS) obtained with the regional climate model MAR, forced by the outputs of three CMIP5 General Circulation Models (GCMs) when considering two different warming scenarios (RCP 4.5 and RCP 8.5). The GCMs selected in this study have been chosen according to their ability to simulate the current climate ove...

Bamber, J. L., Layberry, R. L., and Gogenini, S. P.: A new ice thickness and bed data set for the Greenland ice sheet 1: measurement, data reduction, and errors, J. Geophys. Res., 106, 33773–33780, 2001.; Belleflamme, A., Fettweis, X., Lang, C., and Erpicum, M.: Current and future atmospheric circulation at 500 hPa over Greenland simulated by the CMIP3 and CMIP5 global models, Clim. Dynam., submitted, 2012.; Bengtsson, L., Koumoutsaris, S., and Hodges, K.: L...

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Numerical Modeling of Permafrost Dynamics in Alaska Using a High S...

By: V. E. Romanovsky; S. S. Marchenko; E. E. Jafarov

Description: Geophysical Institute, University of Alaska Fairbanks, USA. Climate projections for the 21st century indicate that there could be a pronounced warming and permafrost degradation in the Arctic and sub-Arctic regions. Climate warming is likely to cause permafrost thawing with subsequent effects on surface albedo, hydrology, soil organic matter storage and greenhouse gas emissions. To assess possible changes in the permafrost thermal state and active layer...

Bader, D. C., Covey, C., Gutowski, W. J. J., Held, I. M., Kunkel, K. E., Miller, R. L., Tokmakian, R. T., and Zhang, M. H.: Climate Models: {A}n Assessment of Strengths and Limitations, Tech. rep., US Climate Change Science Program and the Subcommittee on Global Change Research, Department of Energy, Office of Biological and Environmental Research, Washington, D.C., USA, 2008.; Brewer, M. C.: Some Results of Geothermal Investigations of Permafrost in {N}orthern {A}laska,...

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Solving Richards Equation for Snow Improves Snowpack Meltwater Run...

By: C. Fierz; H. Hirashima; C. Mitterer; M. Lehning; N. Wever

Description: WSL Institute for Snow and Avalanche Research SLF, Flüelastrasse 11, 7260 Davos Dorf, Switzerland. The runoff from the snow cover during spring snow melt or rain-on-snow events is an important factor in the hydrological cycle. In this study, water transport schemes for a 1-dimensional physical based snowpack model are compared to 14 yr of lysimeter measurements at a high alpine site. The schemes include a simple bucket-type approach, an approximati...

Kattelmann, R.: Macropores in snowpacks of {S}ierra {N}evada, Ann. Glaciol., 6, 272–273, 1985.; Bartelt, P. and Lehning, M.: A physical SNOWPACK model for the {S}wiss avalanche warning – {P}art {I}: {n}umerical model, Cold Reg. Sci. Technol., 35, 123–145, doi:10.1016/S0165-232X(02)00074-5, 2002.; Boone, A. and Etchevers, P.: An intercomparison of three snow schemes of varying complexity coupled to the same land ...

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The Greenland Ice Sheet: Modelling the Surface Mass Balance from G...

By: M. Geyer; M. Dumont; E. Brun; D. Salas Y Melia

Description: Météo-France/CNRS, CNRM-GAME UMR3589, Toulouse, France. The aim of this study is to derive a realistic estimation of the Surface Mass Balance (SMB) of the Greenland ice sheet (GrIS) through statistical downscaling of Global Coupled Model (GCM) outputs. To this end, climate simulations performed with the CNRM-CM5.1 Atmosphere-Ocean GCM within the CMIP5 (Coupled Model Intercomparison Project phase 5) framework are used for the period 1850–2...

Amante, C. and Eakins, B. W.: ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis, NOAA Technical Memorandum NESDIS NGDC-24, 19 pp., March 2009.; Bamber, J. L., Griggs, J. A., Hurkmans, R. T. W. L., Dowdeswell, J. A., Gogineni, S. P., Howat, I., Mouginot, J., Paden, J., Palmer, S., Rignot, E., and Steinhage, D.: A new bed elevation dataset for Greenland, The Cryosphere, 7, 499–510, doi:10.5194/tc-...

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Study of a Temperature Gradient Metamorphism of Snow from 3-d Ima...

By: F. Flin; C. Geindreau; B. Lesaffre; N. Calonne; S. Rolland Du Roscoat

Description: Météo-France – CNRS, CNRM-GAME UMR 3589, CEN, 38400 Saint Martin d'Hères, France. We carried out a study to monitor the time evolution of microstructural and physical properties of snow during a temperature gradient metamorphism: a snow slab was subjected to a constant temperature gradient along the vertical during three weeks in a cold-room, and regularly sampled in order to obtain a set of 3-D images using X-ray microtomography. A large panel of prope...

Akitaya, E.: Studies of depth hoar, Low. Temp. Sci. Series A, 26, 1–67, 1974.; Arakawa, H., Izumi, K., Kawashima, K., and Kawamura, T.: Study on quantitative classification of seasonal snow using specific surface area and intrinsic permeability, Cold. Reg. Sci. Technol., 59, 163–168, doi:10.1016/j.coldregions.2009.07.004, 2009.; Auriault, J.-L., Boutin, C., and Geindreau, C.: Homogenization of coupled phenom...

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