TY - JOUR

T1 - Geodetic-Gravimetric Monitoring of Mountain Uplift and Hydrological Variations at Zugspitze and Wank Mountains (Bavarian Alps, Germany)

AU - Timmen, Ludger

AU - Gerlach, Christian

AU - Rehm, Till

AU - Völksen, Christof

AU - Voigt, Christian

N1 - Funding Information: This research was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany?s Excellence Strategy ? EXC ? 2123 QuantumFrontiers ? 390837967 at Leibniz University Hannover. The publication of this article was funded by the Open Access Fund of the Leibniz Universit?t Hannover.

PY - 2021/3/1

Y1 - 2021/3/1

N2 - In 2004, first absolute gravity (AG) measurements were performed on the top of Mt. Zugspitze (2 sites) and at the foot (1 site) and top (1 site) of Mt. Wank. Mt. Wank (summit height 1780 m) and Mt. Zugspitze (2960 m) are about 15 km apart from each other and belong geologically to different parts of the Northern Limestone Alps. Bridging a time span of 15 years, the deduced gravity variations for Zugspitze are in the order of ‐0.30 μm/s² with a standard uncertainty of 0.04 μm/s². The Wank stations (foot and top) show no significant gravity variation. The vertical stability of Wank summit is also confirmed by results of continuous GNSS recordings. Because an Alpine mountain uplift of 1 or 2 mm/yr cannot explain the obtained gravity decline at Zugspitze, the dominating geophysical contributions are assumed to be due to the diminishing glaciers in the vicinity. The modelled gravity trend caused by glacier retreat between epochs 1999 and 2018 amounts to ‐0.012 μm/s²/yr at both Zugspitze AG sites. This explains more than half of the observed gravity decrease. Long‐term variations on inter‐annual and climate‐relevant decadal scale will be investigated in the future using as supplement superconducting gravimetry (installed in 2019) and GNSS equipment (since 2018).

AB - In 2004, first absolute gravity (AG) measurements were performed on the top of Mt. Zugspitze (2 sites) and at the foot (1 site) and top (1 site) of Mt. Wank. Mt. Wank (summit height 1780 m) and Mt. Zugspitze (2960 m) are about 15 km apart from each other and belong geologically to different parts of the Northern Limestone Alps. Bridging a time span of 15 years, the deduced gravity variations for Zugspitze are in the order of ‐0.30 μm/s² with a standard uncertainty of 0.04 μm/s². The Wank stations (foot and top) show no significant gravity variation. The vertical stability of Wank summit is also confirmed by results of continuous GNSS recordings. Because an Alpine mountain uplift of 1 or 2 mm/yr cannot explain the obtained gravity decline at Zugspitze, the dominating geophysical contributions are assumed to be due to the diminishing glaciers in the vicinity. The modelled gravity trend caused by glacier retreat between epochs 1999 and 2018 amounts to ‐0.012 μm/s²/yr at both Zugspitze AG sites. This explains more than half of the observed gravity decrease. Long‐term variations on inter‐annual and climate‐relevant decadal scale will be investigated in the future using as supplement superconducting gravimetry (installed in 2019) and GNSS equipment (since 2018).

KW - Absolute gravimetry

KW - Alpine mountain building

KW - FG5 free‐fall gravimeter

KW - Glacier retreat

KW - GNSS

KW - Gravity variation

KW - Mt. Wank

KW - Mt. Zugspitze

KW - Superconducting gravimeter

UR - http://www.scopus.com/inward/record.url?scp=85102274989&partnerID=8YFLogxK

U2 - 10.3390/rs13050918

DO - 10.3390/rs13050918

M3 - Article

AN - SCOPUS:85102274989

VL - 13

JO - Remote sensing

JF - Remote sensing

SN - 2072-4292

IS - 5

M1 - 918

ER -