New paper! Nature Communications study highlights complex behavior of retreating Antarctic ice

How do grounding line fluctuations affect upstream ice? This is a fundamental question which we have attempted to illuminate using observations of geomorphology on the seafloor of the western Ross Sea. Subglacial and ice-marginal landforms tell us that East Antarctic ice flowed through the Transantarctic Mountains into the Ross Embayment during the Last Glacial Maximum (LGM) to occupy Drygalski, JOIDES, and Pennell troughs. Following the LGM, retreating ice unzipped through JOIDES and Pennell troughs to form a large embayment in the grounding line. This triggered drawdown and enhanced flux through the southern Drygalski outlet glaciers that drove a major reorganization of flow in Drygalski Trough from northward- to southward-flowing and caused ice to readvance about 50 kilometers through southern JOIDES Trough, delivering a significant volume of ice back to the ocean. Click on the image of the manuscript header to read more!

The images below show the configuration of the ice sheet embayment in JOIDES and Pennell Troughs, followed by the configuration of ice after the readvance of outlet glaciers through southern Drygalski Trough into southern JOIDES Trough.

Celebrating World Oceans Day 2017

Over the past few weeks, some other Rice sedimentologists (Travis Swanson—post-doc, Lauren Simkins—post-doc, Tian Dong—Phd student) and I have been developing a demonstration to bring to World Oceans Day at the Houston Museum of Natural Science. Our demonstration, which we have titled “Texas Gulf Coast and its response to sea level rise”, allows students of all ages to learn about what processes cause eustatic and relative sea level rise and how barrier islands like Galveston Island and coastal communities like Houston are affected by higher sea levels and storm surge. We created a hands-on bathtub model demonstrating how land-based ice affects eustatic sea level as it melts, as well as a model of sediment compaction and land subsidence to demonstrate relative sea level rise. Travis Swanson built a wave tank that was modeled after Houston and Galveston Island to demonstrate how barrier islands protect the mainland from storm surge. The tank was built with features that allowed us to raise and lower the water level and choose different wave frequencies. The plastic shark toys that we placed in the water were very effective for demonstrating to small children that sharks would be in their backyards if the sea level rose too much!

See our informational pamphlet, a write-up on the Rice University website, and a video of the event produced by CW39.