Dr. Terence J. Hughes
Department of Earth Sciences/Climate Change Institute/University of Maine
Orono, ME 04469-5790, USA
1 April 2006

2002-2006
In 2002, Quaternary Science Reviews published my paper on the dynamics of calving bays, providing a mechanism for disintegrating former ice sheets after they had been downdrawn close to sea level by surging ice streams. Calving bays migrated up ice streams into Hudson Bay and the Baltic Sea, carving out the hearts of the respective Laurentide and Scandinavian ice sheets, thereby Terminating the last glaciation cycle. This “inside-out” mechanism for deglaciation seems topsy-turvy. In the same issue, Misha Grosswald, George Denton, and I improved the ice-sheet reconstructions done at the University of Maine for CLIMAP twenty years earlier. Misha and I had a field day putting “topsy-turvy” reconstructions of ice sheets in Russia where The Establishment said there were none.

In 2003, Antarctic Science published the paper by Doug Reusch and me that determined the pulling power of Byrd Glacier by calculating the fraction of its basal ice overburden pressure that was supported by basal water pressure, instead of by bedrock. Byrd Glacier pulls more ice out of Antarctica than does any other ice stream. Of course ice streams pulling ice out of ice sheets is topsy-turvy to ice being pushed out.

In 2003, the Journal of Geophysical Research published my paper on the "Geometrical force balance in glaciololgy." Referees were Bob Thomas and Hans Weertman. This was my “topsy-turvy” alternative to integrating the Navier-Stokes equations, updated from my 1992 “pulling power” paper in the Journal of Glaciology, after twelve years. That's progress. My graduate student in physics, Jim Kenneally, and I began publishing our series of papers in Antarctic Science showing how advancing top and bottom crevasses can form and intersect on floating ice shelves that thin by basal melting and creep, and release giant tabular icebergs when crevasses meet. This has been observed on the huge Filchner, Ronne, and Ross ice shelves of West Antarctica in recent years. We provided a mechanism. These papers harkened back to my first papers on ice-shelf disintegration, in 1982 by thinning from creep and melting, and in 1983 by fracture. Back then, there was little interest in calving because that was when ice left the glacier system. However, it entered the larger climate system, a topsy-turvy perspective that makes calving important.

In 2004, Polar Meteorology and Glaciology published, “Greenland Ice Sheet and rising sea leveling a worst-case climate change scenario.” I used my pulling-power approach to model how surface meltwater reaching the bed through crevasses could make Greenland ice streams surge, as in the Jakobshavn Effect. Over a period of 300 years, enough ice would be calved from these ice streams to halt production of North Atlantic Deep Water and throw Europe into another Little Ice Age. That’s a topsy-turvy view showing how ice sheets can trigger rapid climate change, instead of merely responding passively to it.

In 2005, NSF gave the University of Kansas $19 million over five years to establish a science and technology center called the Center for Remote Sensing of Ice Sheets (CReSIS), with the expectation of $20 million more over a second five years. The scientific goal of CReSIS is to link rising sea level with lowering ice sheets over Antarctica and Greenland, with special attention to Thwaites Glacier and Pine Island Glacier in Antarctica, and to Jakobshavn Isbrae in Greenland. These are the very ice streams I had pinpointed for field studies in 1981 and 1986, when that was topsy-turvy thinking. So there’s more progress. The University of Maine (UM) has a piece of the action. We get to model these ice streams and both ice sheets, using all the data coming in from field studies, from Earth-orbiting satellites, from aircraft equipped for remote sensing, and from unmanned remote-controlled surface and air "autonomous platforms" that will collect data along programmed gridlines on the Antarctic and Greenland ice sheets. The University of Kansas (KU) will develop the "autonomous platforms" and participate in all data acquisition. Data acquisition and modeling will also be done at The Ohio State University (OSU) and The Pennsylvania State University (PSU).

In 2006, I will be teaching a two-week glaciology course in June at Elizabeth City State University (ECSU) in North Carolina. ECSU and Haskell Indian Nations University (HINU) in Kansas participate in the minority outreach component of CReSIS. ECSU trains Black students for careers in science and technology. I aim to convince one or two to come to UM and work with me toward doctorates in glaciology, so they can then participate in CReSIS and other glaciological research funded by NSF and NASA. That would be topsy-turvy compared to now. HINU can help prepare American Indians for similar careers. I am now finishing a monograph, Holistic Ice Sheet Modeling: A First-Order Approach, that I will use in my glaciology course at ECSU and then in my courses at UM. If it helps the students, I'll get it published as a textbook in glaciology.

Also in 2006, I'll be doing fieldwork again in Antarctica by participating in Paul Mayewski's American ITASE (ITASE: International Trans-Antarctic Scientific Expeditions) tractor-train traverse from Taylor ice dome near the Dry Valleys to the South Pole. This traverse will include an important side traverse part way up and down an ice flowline from the Russian Vostok Station in central East Antarctica to Byrd Glacier, where I did field work in the 1978-1979 Antarctic summer season. The Russians have extracted a climate record 4 kilometers long in a corehole to subglacial Lake Vostok. Byrd Glacier drains ice from that whole region over which the climate record accumulated for a million years. That will provide the basis for a proposal to NSF to map the floor of Byrd Glacier using gridded radio-echo flightlines along its entire length, so Shamis Fastook and I can do a state-of-the-art computer simulation of its dynamics.

After 2006, I plan to continue with the ITASE traverse from the South Pole through the east side of The Bottleneck between the East and West Antarctic Ice Sheets, and on to the WAIS drilling site on the West Antarctic ice divide where ice flow discharged by Thwaites Glacier begins. An earlier ITASE traverse passed through the west side of The Bottleneck. ITASE data along these traverses will allow Shamis Fastook and me to model collapse of the West Antarctic Ice Sheet into the Pine Island Bay polynya, primarily through Thwaites Glacier, and then to model East Antarctic ice surging into West Antarctica through The Bottleneck after the West Antarctic Ice Sheet is largely downdrawn or even gone completely. Then the West Antarctic ice Sheet can not only form the East Antarctic Ice Sheet, it can get rid of it by sucking out its heart, as I outlined in Ice Sheets (Figure 3.28, page 88) in a worst-case deglaciation scenario. How much more topsy-turvy can you get?

Showing that collapse of the West Antarctic Ice Sheet triggers collapse of the much larger East Antarctic Ice Sheet would be topsy-turvy science of the highest order. To do this correctly, Shamis will need a solution for the full Navier-Stokes equations. But I can provide a first-order solution from my geometrical force balance. If we can pull this off, that will be real progress.

Terry Hughes, April Fool’s Day, 2006