John Hulth

• Hulth, John; Denby, Cecilie Rolstad & Hock, Regine (2013). Estimating glacier snow accumulation from backward calculation of melt and snowline tracking. Annals of Glaciology.  ISSN 0260-3055.  54(62), s 1- 7 . doi: 10.3189/172756413807342965
• Hulth, John; Denby, Cecilie Rolstad; Trondsen, Karoline & Rødby, Ragnhild Wedøe (2010). Surface mass and energy balance of Sørbreen, Jan Mayen, 2008. Annals of Glaciology.  ISSN 0260-3055.  51(55), s 110- 119 Vis sammendrag

  ABSTRACT. Mass-balance measurements were initiated in 2007/08 on Sørbreen, Jan Mayen, including operation of automatic weather stations in the ablation zone. Mean daily melt rate is 3.6cmw.e. d?1 for the investigated snow-free period of 115 days in June?September 2008. During this period, the net radiation is the largest contributor to melt. However, the relative contribution is highest in June (81%) and less in September (21%). The net longwave radiation is negative, acting as a heat sink. The climate on JanMayen is polar maritime with generally high humidity and overcast conditions. This leads to a positive latent heat flux, which represents condensation to the glacier surface. Persistent temperature inversions on the island lead to non-linear lapse rates and an ablation profile where melt does not necessarily decrease with increased elevation. A comparison of air temperatures on the glacier and twice-daily radiosonde ascents from the meteorological station, 20 km away from the glacier, shows that air temperatures at corresponding elevations are highly correlated (R2 = 0.94?0.96). This indicates that radiosonde temperature profiles can be valuable for determining lapse rates for melt modeling of the glacier.

• Hulth, John (2010). Instruments and Methods: Using a draw-wire sensor to continuously monitor glacier melt. Journal of Glaciology.  ISSN 0022-1430.  56(199), s 922- 924 Vis sammendrag

  ABSTRACT. A draw-wire sensor has successfully been used to measure surface lowering due to net ablation of a glacier. A thin steel wire attached to a weight is inserted and frozen into a borehole in the ice. The draw-wire sensor, installed on a tetrahedron on the surface, retracts the wire as the snow or ice melts. Relative surface lowering of the melting surface is recorded in a data logger and may be converted to mass loss. The instrument continuously logs net ablation over several melt seasons and has the potential to be used extensively in future studies of glacier melt, whenever high temporal resolution and precision are required.

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• Lefeuvre, Pierre-Marie & Hulth, John (2018). Augmented Reality Sandbox: Lag ditt eget 3d landskap - Få vannet til å strømme. Shape your own 3D landscape - Make water flow. Vis sammendrag

  The AR sandbox is an innovative internationally-recognised education tool to engage kids, pupils and students in introductory classes by presenting concepts in mapping and surface processes. The real-time projection are powered by a PC that processes on the fly elevation of the sand from a distance sensor, the Kinect, and projects colours and contour lines onto the sandbox. Using this immersive and interactive 3D visualisation of the sand surface, students learn the meaning of a contour line and map projection. Water flow is also modelled and updates as the sand is shaped by the students. Construct a lake on top of a volcano, a gully draining water or even a dam to understand the important concept of a watershed.

• Burkhart, John; Decker, Sven; Filhol, Simon; Hulth, John; Nesje, Atle; Schuler, Thomas; Sobolowski, Stefan Pieter & Tallaksen, Lena M. (2017). Development of the Finse Alpine Research Station towards a platform for multi-disciplinary research on Land-Atmosphere Interaction in Cold Environments (LATICE).
• Filhol, Simon; Schuler, Thomas; Burkhart, John; Hulth, John & Decker, Sven (2017). A network of instrumentation to keep track of snow distribution at Finse, Norway.
• Burkhart, John; Schuler, Thomas; Tallaksen, Lena M.; Filhol, Simon; Hulth, John & Decker, Sven (2016). Snow model validation in Norway at the Land Atmosphere Interaction in Cold Environments (LATICE) Finse site.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). A distributed and real-time wireless network of weather stations for wind-blown snow at Finse, Norway.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). Capturing snow depth distribution with a low cost and wireless weather station network.
• Filhol, Simon; Burkhart, John; Schuler, Thomas & Hulth, John (2016). Weather stations for wind-blown snow at Finse, Norway: A distributed and real-time wireless network of.
• Schuler, Thomas; Aalstad, Kristoffer; Aas, Kjetil Schanke; Burkhart, John; Dunse, Thorben; Filhol, Simon; Hulth, John; Østby, Torbjørn Ims & Westermann, Sebastian (2016). Towards real-time snow products for Svalbard.
• Denby, Cecilie Rolstad & Hulth, John (2012). Estimating glacier snow accumulation from backward calculation of melt and snowline tracking.
• Denby, Cecilie Rolstad; Malnes, Eirik; Burud, Ingunn; Hulth, John & Hock, Regine (2012). Envisat ASAR and meteorological measurments for determination of the spatial extent of glacier snow melt on Jan Mayen, 2009.
• Denby, Cecilie, Rolstad & Hulth, John (2011). Assessment of differentiated surface elevation data from 1949, 1975 and 2008 for estimates of ice-volume changes at Jan Mayen. Journal of Glaciology.  ISSN 0022-1430.  57(205), s 976- 980
• Hulth, John; Rolstad, Cecilie & Hock, Regine (2009). Radiosonde data for temperature lapse rates and radiation transmissivity indexs in a distributed temperature-index melt model of Sørbreen, Jan Mayen.
• Rolstad, Cecilie & Hulth, John (2009). The direct glaciological mass- and energy balance of Sørbreen, Jan Mayen, for the ablation season 2008.
• Hock, Regine & Hulth, John (2008). Mass Balance of Storglaciären, Sweden: Assessment of uncertainties.
• Hock, Regine & Hulth, John (2008). Mass balance of Storglaciären, Sweden: Re-evaluation and error assessment.
• Hulth, John (2008). Glaciological field work on Jan Mayen.
• Hulth, John & Hock, Regine (2008). Statistical analysis of the spatial and temporal variability of winter mass balance of Storglaciären.

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