From the WOODS HOLE OCEANOGRAPHIC INSTITUTION and the “worse than we thought” department, comes this breathless press release that doesn’t even mention the name of the study somehow manages to spin model results into a future frenzy worse that if the ice shelves just collapsed.
New study projects that melting of Antarctic ice shelves will intensify
New research published on October 12th projects a doubling of surface melting of Antarctic ice shelves by 2050 and that by 2100 melting may surpass intensities associated with ice shelf collapse, if greenhouse gas emissions from fossil fuel consumption continue at the present rate.
Ice shelves are the floating extensions of the continent’s massive land-based ice sheets. While the melting or breakup of floating ice shelves does not directly raise sea level, ice shelves do have a “door stop” effect: They slow the flow of ice from glaciers and ice sheets into the ocean, where it melts and raises sea levels.
“Our results illustrate just how rapidly melting in Antarctica can intensify in a warming climate,” said Luke Trusel, lead author and postdoctoral scholar at Woods Hole Oceanographic Institution (WHOI). “This has already occurred in places like the Antarctic Peninsula where we’ve observed warming and abrupt ice shelf collapses in the last few decades. Our model projections show that similar levels of melt may occur across coastal Antarctica near the end of this century, raising concerns about future ice shelf stability.”
The study, published Oct. 12, 2015, in Nature Geoscience, was conducted by Trusel, Clark University Associate Professor of Geography Karen Frey, WHOI scientists Sarah Das and Kristopher Karnauskas, Peter Kuipers Munneke and Michiel R. van den Broeke of the Institute for Marine and Atmospheric Research Utrecht University, and Erik van Meijgaard of the Royal Netherlands Meteorological Institute.
To study how melting evolves over time and to predict future ice sheet melting along the entire Antarctic coastline, the scientists combined satellite observations of ice surface melting with climate model simulations under scenarios of intermediate and high levels of greenhouse gas emissions until the year 2100.
The results indicate a strong potential for the doubling of Antarctica-wide ice sheet surface melting by 2050, under either emissions scenario. However, between 2050 and 2100, the models reveal a significant divergence between the two scenarios. Under the high-emissions climate scenario, by 2100 ice sheet surface melting approaches or exceeds intensities associated with ice shelf collapse in the past. Under the reduced-emissions scenario, there is relatively little increase in ice sheet melting after the doubling in 2050.
“The data presented in this study clearly show that climate policy, and therefore the trajectory of greenhouse gas emissions over the coming century, have an enormous control over the future fate of surface melting of Antarctic ice shelves, which we must consider when assessing their long-term stability and potential indirect contributions to sea level rise,” said Frey.
Funding for the research was provided by NASA, the Doherty Postdoctoral Scholarship Program at WHOI, the Netherlands Earth System Science Centre, the Polar Program of the Netherlands Organization of Scientific Research, and the Dutch Ministry of Infrastructure and the Environment.
Since these bozos that wrote the press release didn’t provide a link to the study, I will.
Divergent trajectories of Antarctic surface melt under two twenty-first-century climate scenarios
Ice shelves modulate Antarctic contributions to sea-level rise1 and thereby represent a critical, climate-sensitive interface between the Antarctic ice sheet and the global ocean. Following rapid atmospheric warming over the past decades2, 3, Antarctic Peninsula ice shelves have progressively retreated4, at times catastrophically5. This decay supports hypotheses of thermal limits of viability for ice shelves via surface melt forcing3, 5, 6. Here we use a polar-adapted regional climate model7 and satellite observations8 to quantify the nonlinear relationship between surface melting and summer air temperature. Combining observations and multimodel simulations, we examine melt evolution and intensification before observed ice shelf collapse on the Antarctic Peninsula. We then assess the twenty-first-century evolution of surface melt across Antarctica under intermediate and high emissions climate scenarios. Our projections reveal a scenario-independent doubling of Antarctic-wide melt by 2050. Between 2050 and 2100, however, significant divergence in melt occurs between the two climate scenarios. Under the high emissions pathway by 2100, melt on several ice shelves approaches or surpasses intensities that have historically been associated with ice shelf collapse, at least on the northeast Antarctic Peninsula.