BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//pretalx//talks.staging.osgeo.org//foss4g-it-2023//speaker//GMCUUS
BEGIN:VTIMEZONE
TZID:GMT
BEGIN:STANDARD
DTSTART:20001029T030000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:GMT
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:20000326T020000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3
TZNAME:BST
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
END:DAYLIGHT
END:VTIMEZONE
BEGIN:VEVENT
UID:pretalx-foss4g-it-2023-AHR93Z@talks.staging.osgeo.org
DTSTART;TZID=GMT:20230612T164500
DTEND;TZID=GMT:20230612T170000
DESCRIPTION:Debris covered glaciers are common in many parts of the world a
 nd contribute to the hydrological cycle and freshwater availability in ari
 d regions. In the Italian Alps\, some of the largest debris covered glacie
 rs are located in the Mont Blanc group and among them Brenva glacier (5.95
  km2 in the latest glacier inventory\, Paul et al. 2020) reaches the lowes
 t terminus elevation on the southern side of the Alps at 1415 m a.s.l.. Th
 e debris supply originated from several rockfall events throughout the Hol
 ocene\, with the most recent ones in 1920s and in 1997. In 2004\, the ice 
 flow was interrupted from the icefall to the glacier tongue\, and this led
  to enhanced ice stagnation and mass wasting. To investigate the recent ev
 olution of the glacier tongue\, we carried out two UAV surveys in 2019 and
  2020\, using a DJI Mavic and DJI Phantom 4 RTK drones. During the first s
 urvey\, ground control points were used to increase the accuracy of the fi
 nal products\, while during the second survey we relied on RTK corrections
  to improve geolocation. The acquired images were processed using a struct
 ure from motion pipeline and yielded high resolution orthomosaics and DEMs
 . By comparing the DEMs from the two photogrammetric surveys\, we were abl
 e to describe the rapid thinning of the ice tongue\, which lost more than 
 40 m over one year only. Downwasting of the ice was faboured by the format
 ion of epiglacial lakes\, which enhance melt. By generating DEMs and ortho
 mosaics from aerial data\, we reconstructed the recent history of the glac
 ier\, showing an initial phase of mass transfer from the rockfall and the 
 subsequent melt out of the ice tongue.
DTSTAMP:20260516T234918Z
LOCATION:Sala Biblioteca @ PoliBa
SUMMARY:Extreme mass loss of Brenva glacier from UAV surveys - Davide Fugaz
 za\, Fabrizio Troilo
URL:https://talks.staging.osgeo.org/foss4g-it-2023/talk/AHR93Z/
END:VEVENT
END:VCALENDAR