扫描欧洲顶端

即使对最有经验的高级主义者来说，到达欧洲最高峰的蒙特·布兰克（Mont Blanc）的顶部也是一个巨大的挑战 - 不仅是因为其海拔高度，而且还因为其恶劣天气条件。山顶上的强风和降雪不断导致山冰盖的高度和体积波动。这促使一个专家测量师团队应对山的挑战，每两年使用最新的测量技术来确定冰盖的实际变化。今年，一支由法国Leica Geosystems的两名测量师和总部位于法国上萨沃伊地区的特许土地测量师组成的团队，决定使用Leica Nova MS50跨国公司进行该传奇冰川的形状和数量的首次3D激光扫描。

14名登山者团队包括测量师及其技术合作伙伴：Covadis（Géomédia），Teria（Exagone）和Leica Geosystems。他们由向导，摄影师和摄影师陪同。Leica Geosystems负责测量Mont Blanc冰盖的高程和形状，由Farouk Kadded是法国LGS的产品经理Farouk Kadded，他是一位经验丰富的Alpinist，并建立了与Upper Savoy地区的测量师建立的合作伙伴关系。Farouk自2001年以来就参加了这次探险活动，并解释了为什么2013年为这次冒险提供新的技术维度提供了机会。

Farouk says, “It seemed altogether appropriate to use the world’s first MultiStation, the Leica Nova MS50, to capture the first ever 3D laser scan of the Mont Blanc ice cap. This would save time and provide higher point density than GPS measurements, which we took in previous years. With such extreme temperatures and with wind chill factors of – 10°C (14°F), fast data collection is a real bonus. For the first time, we had at our disposal an instrument that not only combines the latest technologies in the fields of total station measurements, digital imagery, 3D laser scanning and GNSS positioning but is also designed to operate in extreme conditions. Our only consideration was the additional weight. Transporting the instrument to the summit added about seven kilograms to my backpack but the results were certainly worth it.”

测量大使
After taking a deep breath and appreciating the extraordinary view, the team had little time to lose. The temperature felt like – 25°C (– 13°F), with gusting winds of over 50 km/h (31 mph). In order to make a 3D laser scan of the ice cap, they had to quickly prepare and set up the Leica Nova MS50 MultiStation as well as two Leica Viva GS14 receivers: one for taking precise altitude measurements that would later be analysed during post-processing and one receiver on a pole for taking kinematic measurements.

后建立的第一个GNSS天线两种urs of observation, the surveyors got started with the second antenna that would take approximately one hundred measurements of the ice cap. At the same time, Farouk, in charge of the MultiStation, positioned it to scan the ice cap. Minutes later, it recorded almost 100,000 points, despite freezing conditions, which were immediately displayed on the MultiStation’s screen. This confirmed that the survey was complete and the team could begin their descent.

调查公司的所有者，内阁博雷尔（Cabinet Borrel），探险队的一位经验丰富的成员菲利普·博雷尔（Philippe Borrel）表示：“使用Nova MS50多站模型对Mont Blanc Summit进行建模是一种精确测量的练习，与传统地形相比，准确性更高。在这种敌对的环境中工作时，数据收集的速度和能够使用最小数量的控制点尤其有利。考虑到我们必须攀登的岩石地形，陡峭的斜坡和大风山脊，我们大大减少了完成工作所需的时间和能量，使多站的大小和重量变得令人惊讶地容易。”

What were the exact measurements of Mont Blanc?
The 2013 expedition proved that the current elevation of Mont Blanc is 4,810.02 m (15,780.91 ft), which is 42 cm (16.5 in) less than in 2011. The actual rock summit has an altitude of 4,792 m (15,722 ft), however the snow covering the peak may vary the actual summit’s altitude anywhere from 15 to 20 m (49 to 66 ft). Expedition partner Géomédia calculated the volume of the ice cap covering the rocky summit at 20,213 m³ (26,438 yd³) and produced a 3D animation from the scan data as well. In the future, these results will help researchers determine possible changes to the ice cap caused by global warming.

Farouk Kadded noted, “The MultiStation added a new dimension to the measurement campaign enabling us to produce, for the first time, a precise 3D model of the ice cap of Mont Blanc. Collecting data to millimetre accuracy is a human and technical achievement and this campaign demonstrated that this technology is at the top of its game.”

Written by Marie-Caroline Rondeau