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Today’s big news. The height of Mont Blanc is 129 cm lower than in 2013. Read on for the full story:
Mont Blanc was First climbed on August 8 1786. In 1863, the official height was measured as 4807 meters. At some point after then it became 4809m. That’s the height given by Wikipedia. Now it is recognised as 4810m. The IGN (Institut Géographique National) have it at this height on their maps. You can take a look here.
Every two years since since 2001 the height of Mont Blanc has been measured to keep a track of the amount of snow on the summit. The result so far.
2001 : 4 810,40 m
2003 : 4 808,45 m
2005 : 4 808,75 m
2007 : 4 810,90 m
2009 : 4 810,45 m
2011 : 4 810,44 m
2013 : 4 810,02 m
2015 : 4 808,73 m
A full report on the current measurement can be found on the Dauphine Libere website. http://www.ledauphine.com/haute-savoie/2015/09/10/l-altitude-du-mont-blanc-mesuree-a-4-808-73-metres. In fact the height of the solid bit (rock not snow) is only 4 792m, the rest is the snow cover, up to 18m of it! The summit moves around depending on the prevailing wind and amount of precipitation. In 2009 the summit was 34 m further East than now.
September is the time of year when there is least snow on the mountain. This does not tally with the height measured in May (greatest snow depth) of this year at 4807,88m. The discrepancy is probably down to the winds.
These pictures where all taken on a ski trip to the summit in June 2009. the top one shows the route. The summer walking route takes a different line.