A break in the clouds revealed Johns Hopkins Glacier and Inlet below the aircraft. This glacier is about a mile wide and 250 feet high at the terminus and 200 feet deep at the water line.

For the lucky modern day explorer in southeast Alaska, the view from the aircraft will provide more than awe-inspiring mountains stretching their long charcoal ridges into a sea of white clouds. One hopes the sea will part, as it did this early July day, to reveal the white snowfields, light turquoise glaciers, and blue-green fjords of Glacier Bay, Alaska.
“Johns Hopkins Inlet looks open, even passable,” commented Dr. Daniel Lawson, Research Physical Scientist for the U.S. Army Cold Regions Research and Engineering Lab (CRREL) based in Hanover, New Hampshire, with an office at Fort Richardson, Alaska. This inlet is often so full of icebergs that ships cannot maneuver close to the glacier. During this trip, Lawson hopes his research team can work their way up the inlet to check a rain and water level gauge, install a temperature gauge, profile the water characteristics in the inlet, and conduct a survey of the bottom of the inlet. This is just one of his long list of sites to explore using modern day technology.
Lawson calls Bradford, Vermont, home but has been on assignment for the past five years at Fort Richardson, Alaska, where he has started applied and basic research programs for CRREL, with a recent emphasis on site characterization for environmental clean-up of Army installations. For more than a decade, Lawson has also conducted studies of glacial, marine and physical systems in Glacier Bay National Park and Preserve, located northwest of Juneau on the northern end of the Alaskan panhandle. His goal is to gain knowledge of the glacier and glacial-marine systems, their movement and their response to climate, and to reconstruct the glacial history and past climates. His method is to lead teams of researchers into the park aboard the National Park Service vessel, Nunatak. In July the research team included Lawson, Susan Bigl of Bradford, Dr. Lewis Hunter of Thetford, Ron Bailey of Lebanon, and Paul Cedfeldt formerly of Wilder now living in Portland, Oregon, along with the Nunatak Captain Jim Luthy and First Mate Chris Frary.
“The only constant in Glacier Bay is change,” said Lawson. He has lost track of how many trips he has made “up bay” over the past 10 years to study the constant change, but he estimates the total number of days equals at least two years.
“To understand the environment, you need to go there and observe it, touch it, feel it, be a part of it. In geology, the present is the key to the past. The present and the past together hold the key to the future,” said Lawson.
Glacier Bay National Park provides Lawson and his colleagues with a unique laboratory. The region is a dynamic environment sensitive to climate changes. As a National Park, the area has been protected from human intervention and is accessible to scientists through the Park Service. This region provides a wealth of information about glacial response to climate change in the present day. Lawson and others use these clues to reconstruct how glaciers responded in the past and to predict the response of natural systems in the future.
What the casual observer might notice as “change” when traveling from one rainy inlet around the bend to another with filtered sun, Lawson wants to document by collecting precipitation and temperature data across the park. While tourists on the decks of passing cruise ships “ooh” and “ah” at the dramatic calving of ice chunks from the face of the glacier, team members use lasers to measure the advancing/retreating ice margins and a fathometer (sonar) to map the topography of the bottom of the inlet. On shore, a safe distance from brown and black bears and under the watchful eyes of soaring eagles, Lawson searches in valleys and rivers for stumps from the ancient forests that grew between ice advances and have been preserved beneath advancing ice and sediment.

The jagged spires of McBride Glacier jut 200 feet above and the ice decends over 300 feet below the water line.

British Captain George Vancouver first noted the ice sheet that filled what is now Glacier Bay in 1794. Chunks of ice from the glacier choked Icy Strait, the passage along Alaska’s northern panhandle. Over the next century, this massive ice sheet retreated over 35 miles and revealed a natural laboratory for the study of glaciers, past and present. Through maps, notes, and photographs, the past two hundred years of change have been well documented by great explorers and scientists.
An early explorer and naturalist, John Muir, came to Glacier Bay in 1879 seeking knowledge to support a theory that worldwide glaciation rather than the biblical flood created modern day landforms. In his memoir, Travels in Alaska, he describes “the crystal bluffs of the vast glacier, the intensely white, far-spreading fields of ice.”
Today, just over a century after Muir built his cabin at the glacier margin, he would look out from Muir Point in the shadow of 5139-foot Mount Wright to see a deep fjord flanked by sheer cliffs and the beginnings of revegetation. The glacier that bears his name is now over 25 miles away and no longer touches the tidewater. The inlet revealed by the retreating glacier was the location of study several days into Lawson’s July trip.
In calm, clear waters, Captain Luthy steered the Nunatak up Muir Inlet in the east arm of the park from anchorage in Wolf Cove, past the jagged, blue spires of the 200 foot-high face of McBride Glacier and the curving 15-mile descent of Riggs Glacier. Luthy commented that in the early 1970’s when Riggs was active, huge icebergs the size of moderate-sized houses would fill the inlet. What would have taken the Nunatak a full day to maneuver could now be traveled in 11/2 hours, leaving time for research.
In the morning, one crew boarded a skiff and slowly motored back and forth across upper Muir Inlet to conduct a bathymetric survey of the bottom of the inlet. Bathymetric surveys done over several years will be compared to determine sedimentation and erosion rates.
“With this basic research, we begin to understand what occurs in the natural systems, glacial and land, and the interaction of these with the marine system of the fjords,” explained Lawson. He shares this research with marine biologists to help in their ongoing research in the Park and continues to question the dynamics of physical systems. “Where is the sediment moving and how will it affect the marine environment? Where does the material end up? If it is redeposited off-shore along the continental margin, we can study the sequences of material and learn what happened over 12,000 to perhaps 60,000 or more years ago.”
Back aboard the Nunatak, a second crew lowered a Conductivity-Temperature-Depth (CTD) instrument to the bottom to profile the water characteristics in the inlet. Long-term, site-specific oceanographic surveys with the CTD Profiler examine tidal, seasonal, and annual variability in fjord water characteristics including temperature and water quality (sediments, minerals, and chemical composition). The data will be used to analyze seasonal and annual changes in sediment discharge from the glaciers in an effort to understand both sub-glacial activity and the effects of the sediments on the marine environment.
In the afternoon, the first crew reinstalled a tide gauge and then hiked under sunny skies to occupy Muir Photographic Station 37, while the second crew searched a valley for ancient logs and stumps. The tide gauge located at the base of Riggs Glacier collects data on tidal fluctuations. This data is made available to the Park and marine ecosystem investigators and used in part to analyze oceanographic trends and to help identify areas that could be impacted by human activity in the Park.
After several days of skiffing and bathymetry, stepping ashore and climbing up the steep slope to a photographic station above Muir Glacier was a welcome, albeit quick, diversion from basic scientific research on a rare clear day. The survey and photographic stations throughout the Park were established by Dr. William O. Field after his first trip to Glacier Bay in 1929. He noticed the dramatic changes in the ice positions documented by pioneering glaciologist Harry Fielding Reid in 1890. Where Reid’s maps showed solid ice, Field found water. Official photographers continue Field’s photographic record with the help of unofficial photographers who find the cairns. Muir Station 37 continues to be occupied and the ice margin photographed by CRREL scientists.
In a nearby valley, the other crew hiked in search of ancient logs and stumps for radiocarbon dating and tree-ring analysis. As the sediments erode, trees that were buried by the glacier are uncovered. By collecting, dating, and studying the tree rings of numerous samples from each time period of ice advance and retreat, Lawson hopes to develop a continuous record dating from the present back 9000 years. This would be the only such record in sub-arctic North America and would be invaluable to understanding the climate through that time.
“It’s a race against time,” said Lawson of his search for ancient wood. “There is an urgency to this research. We need to repeatedly get to as many valleys and mountain slopes as we can to sample the wood just as it is uncovered by erosion of the sediments. If the wood is left exposed, it will rot, and the record is lost. If we wait, the samples will be hidden by the vegetation.”
Three days later, in the west arm of the park, the Nunatak continued to enjoy calm weather with an anchorage in the shadow of Reid Glacier. As the sun worked its way in and out of the scarf of clouds encircling the mountains, one team skiffed to Johns Hopkins Inlet around car-sized icebergs, past the tall, jagged face of Lamplugh Glacier and along the valley below Topeka Glacier. The team had scoured this valley earlier in the trip for a scrap of ancient wood with no luck. Lawson plans to look again and again for the elusive fragments that could unlock the secrets of the past.
As Lawson had hoped from the airplane, Johns Hopkins Inlet was passable by dodging chunks of ice and he could get to the gauges for the first time in over a year of trips. The existing water level and rain gauges were checked and a recording temperature gauge was installed while large chunks of ice crashed from the imposing face (250 feet high) of the advancing glacier into the inlet, shooting water up over a 100 feet into the crisp air, and creating waves large enough to swamp a skiff if unattended.
Though Lawson has a jump start on collecting weather, water, and ice data, his vision includes permanent weather stations with remote access via satellite for scientific as well as Park Ranger use. In his search for keys to unlock the past, his team has only just begun to acquire samples for tree-ring analysis. His goal would be to send teams of researchers to collect and analyze the rings to understand the advances and retreats of the glaciers and the climatic conditions to create a 9000-year record. All this basic research, he hopes, will lead to an understanding of the Park’s physical environment and glacial systems from the mountaintops through the ice margins down to the bottom of the inlets and out to the continental margins.
“The more often you go to Glacier Bay, the more you can learn. Yes, you can use computers and remote sensing to measure and model, but it is the direct observation that validates the models,” said Lawson. “Everyday in Glacier Bay, we learn or discover something new as we try to understand the world we live in. In Glacier Bay, we can observe changes during our lifetime, instead of on a geologic time scale."