Ice streams: Charting the history of the ice caps

The relationship between ice streams and climate change forms the basis of the article "Stemming the flow of climate change," published in the journal International Innovation by Angelo Camerlenghi, an ICREA research professor with the Department of Stratigraphy, Paleontology and Marine Geosciences at the University of Barcelona, and Michele Rebesco, from the National Institute of Oceanography and Geophysics in Trieste. The study was carried out under the project "Neogene Ice-Streams and Sedimentary Processes on High-Latitude Continental Margins" (NICE-STREAMS), which is one of a series of research initiatives conducted under the International Polar Year (IPY) Directive.

The journal International Innovation, which devotes is latest edition to ground-breaking international research into global climate change, contains interviews with Connie Hedegaard, EC Commissioner for Climate Action, Ghassem Asrar, director of the World Climate Research Program, and Jacqueline McGlade, executive secretary of the European Environment Agency, and with a number of other international experts.

Ice streams are one of the most dynamic elements of large ice masses and have shaped the seafloor of the Polar Regions over thousands of years. The streams are found at the edges of ice sheets and are the principal pathways through which ice from the interior of continent is unloaded and drained, leaving deep scars in the marine topography. For scientists, studying the polar ice streams of the past is the key to understanding ocean-climate interactions and the stability of large ice masses, and will help to improve simulations and predictive models of future climate change. As explained by Dr. Angelo Camerlenghi, coordinator of the NICE-STREAMS project and a member of the Marine Geosciences Research Group, "Studying the ice streams of the past is fundamental in understanding present-day ice dynamics and their link to climate change."

The Marine Geosciences Research Group, directed at the UB by Miquel Canals, is formed by a team of distinguished scientists with extensive experience in the study of fast-flowing ice streams in Antarctica and who have published groundbreaking work on the geological evidence left by ice streams on the ocean floor around the Antarctic Peninsula. The NICE-STREAMS project, which is supported by the University of Tromsø in Norway, is aimed at designing new models of fast-flowing ice streams based on geological records, and encompasses areas of study in both hemispheres. To date, the project team has mapped more than 30,000 square kilometres of sea bed using high-resolution bathymetry and obtained almost 2,000 kilometres of seismic reflection profile.

According to experts, one of the most complex aspects in climate change studies is to determine whether the alterations studied are natural or the result of human influence. "We should remember that natural climate change is part of the Earth's physiology. Distinguishing between natural and anthropogenic origins of climate change is one of our most difficult challenges," explains Michele Rebesco.

Camerlenghi adds that, "Geological reconstructions of natural change in the past show clearly that our climate is changing more rapidly than ever. Model predictions tend to be contradicted by observations, which have shown in recent years that the response is much faster than suggested by the simulations. Our studies of the recent past will hopefully provide the ideal data for improving predictive models." Dr. Camerlenghi also directed the SVAIS project which analysed the morphology of the ocean floor and natural evidence of climate change in the Fram Strait -- where cold water from the Arctic Ocean meets warmer water from the Atlantic -- for the period from three million years ago until the most recent deglaciation, which occurred between 20,000 and 10,000 years ago, a period of particular interest to scientists during which the melting of continental ice increased the input of fresh water into the world's oceans.