Workers unravelling a vast tarpaulin down the slopes of the glinting Presena glacier. The glacier in northern Italy has lost over one-third of its volume since 1993 and the tarpaulin is meant to protect the alpine ice from global warming. Once the ski season is over and cable cars are berthed, conservationists race to try and stop the ice from melting by using white tarps to block the sun's rays. "This area is continuously shrinking, so we cover as much of it as possible," says Mr Davide Panizza, who heads the Carosello-Tonale company doing the job. From around 30,000 sq m covered in 2008 when the project began, his team now places 100,000 sq m under wraps. The coverings are "geotextile tarpaulins that reflect sunlight, maintaining a temperature lower than the external one, and thus preserving as much snow as possible," he told Agence France-Press. On the border between the Lombardy and Trentino Alto Adige regions, workers unroll the sheets in long strips, covering an area at an altitude of 2,700m to 3,000m. Once in place, the sheets are hardly distinguishable from the packed white snow beneath.