This week’s Imaggeo on Mondays is brought to you by Joanna Nield, a lecturer in physical geography at the University of Southampton. Nield explains how volcanic eruptions can impact glaciers and how ash fall can both accelerate and slow down glacial melt… This photo was taken at Fjallsjökull, Iceland in July 2011, shortly after the eruption of Grímsvötn volcano (21 – 30 May 2011). The Gríms ...[Read More]
Imaggeo on Mondays: How to forge a fjord
The West Norwegian Fjords are the reference point for fjords around the world. One such fjord is Geiranger, which features in this week’s Imaggeo on Mondays. The geological setting of Geirangerfjord – and its climate – has earned the area a spot on UNESCO’s World Heritage List. During the last ice age, much of northern Europe was glaciated; covered by a large ice sheet known as the Fennoscandian I ...[Read More]
Geosciences Column: Getting a handle on glacial lakes
Glacial lake outburst floods (GLOFs) are caused when masses of meltwater are released from behind a glacier moraine. Moraines are piles of unconsolidated debris that have either eroded from the glacier valley or have been deposited by melting glaciers. When they fail, a huge volume of water can be released, threatening populations further down the valley. Moraine failure can be caused by avalanche ...[Read More]
Geosciences column: Playing back the Antarctic ice records
Satellites are keeping tabs on the state of Arctic and Antarctic sea ice, and have observed considerable declines in ice extent in many areas since records began, but what do we know of past sea ice extent? Ice cores keep an excellent record of climate change, but until recently, ice cores have not been used to quantify patterns in past sea ice extent because few reliable compounds are preserved i ...[Read More]