Four very large rock falls in the Italian Dolomite mountain range in the past few weeks, including one of the smaller columns of the "Cinque Torre" above Cortina D'Ampezzo and the top of the "Piccolo Cir" above the Passo di Gardena, are causing concern.

Local scientists have blamed the Dolomite falls on natural thermo-elastic erosion, when snow and ice thaw during the day and the water seeps into the rock to then freeze again during the night, expanding and causing the rock to crack.

Scientists from Switzerland, Germany and Scotland have recently published new findings following research done in the Alps over the past three years. Devices inserted in the rock face in 22 different places to record temperature showed that higher summer temperatures heat some rock faces so much that permafrost deep in the rock which acts as a glue, begins to melt, decreasing its stability .

While the extreme heat of the summer of 2003 is thought to have caused the recent Dolomite falls, global warming over an extended period could seriously affect the Italian mountain ranges which are particularly vulnerable being relatively warm and having only marginal permafrost.

There were more than 50 deaths caused by rock falls in the Alps in 2003.