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At present there is a wide variety of geomatic techniques available to determine the dynamics of glaciers, rock glaciers and ice patches. Between 1991 and 2012, different geomatic techniques – total station, global positioning system, close‐range photogrammetry and terrestrial laser scanner – were applied to monitor the movement of cryosphere landforms in the high mountains of the Iberian Peninsula. The applied techniques must be adapted to the dynamic conditions of cryospheric environments, and so there is no ideal general technique, and depending on the characteristics of the geomorphological structure to be studied, different geomatic techniques can be used. However, there are situations in which certain instruments cannot be used: global positioning system–real time kinematics shows difficulties when the presence of vertical walls cause a ‘multipath’ effect. The technique that provides the best results in each case must be chosen, although they can all give good results in measuring and monitoring geomorphological processes. This paper analyses the techniques used and results on vertical and horizontal changes of glaciers, rock glaciers and ice patches in the Sierra Nevada, Pyrenees and Picos de Europa, and differences among them by location and topoclimatic setting. All glaciers and rock glaciers show a thinning tendency and annual variations in the flow velocity. In addition to the specific dynamic analysis, the geomatic techniques can be used to detail scale and volume changes and perimeter of the analysed landforms.

Popocatépetl (19°02’ N, 98°62’W; 5424 m) is one of the largest active stratovolcanoes in the Transmexican Volcanic Belt. A glacier located on the north side has undergone severe ablation since the volcano reinitiated eruptive activity in December 1994. In our study, we calculate the extent of the glacier recession and the loss in glacial mass balance during the period of greatest laharic activity (1994–2002), using photogrammetric treatment of 20 pairs of aerial photographs. The results indicate that from November 1997 to December 2002, the glacier released approximately 3 967 000 m3 of water. A period of intense glacier melting occurred from 4 November 2000 to 15 March 2001 during which time 717 000 m3 of water was released. Much of the melting was attributed to the pyroclastic flow that took place on 22 January 2001 and produced a 14.2 km lahar with 68 000 m3 of water. Among the many types of volcanic events, pyroclastic flows were the most effective in causing sudden snowmelt, although small explosions were also effective since they deposited incandescent material on the glacier. The collapse of the plinian columns covered the glacier with pyroclasts and increased its volume. The existence of control points for georeferencing and a knowledge of the topography underlying the glacier previous to the eruption would have provided more accurate and useful results for hazard prevention.

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