New research carried out by a team of scientists headed by Durham University researchers has discovered that ice-loss events which have occurred in the past could have caused sea levels to rise by up to 3.6 metres per century. Data from this research could help to predict how the landscape will continue to change if we do nothing to curb the current trajectory of climate change.
Records show that at the end of the last ice age (around 14,600 years ago) sea levels rose at around 10 times the current rate, meaning an overall rise of 18-metres. Previously, there has been much disagreement as to which ice sheet was responsible for the rise, with evidence suggesting both the Antarctic Ice Sheet and other sheets in the Northern Hemisphere were contributors. Indeed, lead author of this research, Mr Yucheng Lin (Department of Geography at Durham University) states that: “Despite being identified over 30 years ago, it has been surprisingly challenging to determine which ice sheet was the major contributor to this dramatic rise in sea levels.” Lin goes on to discuss how the majority of previous studies “disagreed with geological records of ice sheet change” and explains how data from lakes on the coast of Scotland was implemented to aid researchers to accurately identify the sources of meltwater.
Co-author Dr. Pippa Whitehouse explains that the study has determined that much of the meltwater seems to have originated from the former North American and Eurasian ice sheets, with only a slight contribution from Antarctica, and this knowledge will help to create more accurate models to predict future climactic changes.
This unprecedented release of freshwater into the sea – which is comparable to the melting of an ice sheet double the size of Greenland in the course of 500 years – has not only flooded low-lying land but will also have disrupted ocean circulation, thereby impacting further on climate change. Ice-ocean-climate interactions shape terrestrial weather patterns, and the study’s findings are particularly relevant as the current rapid melting of the Greenland ice sheet – which has the potential to disrupt the Gulf Stream – will continue to impact upon changes in sea levels and global ocean circulation.
The researchers are now keen to discover what triggered this ice melt, and how the influx of meltwater will continue to affect ocean currents in the North Atlantic and consequently, climate change in the UK.
Image: Professor Ian Shennan, Department of Geography, Durham University.