In the presence of icebergs

It was four degrees below freezing and sheets of rain were driving in at a truculent angle. Anna, our Tayana 37 cutter, was running before a light gale that whipped her through the Dixon Entrance, on her open crossing from Prince Rupert, British Columbia to Ketchikan, Alaska. The strong current and following seas were giving us a 2-knot lift across the entrance, and the latest cold front in late spring was a good sign, as we were sailing a long way to visit the ice, in Southeast Alaska.

After a year of voyaging in the tropics, we were happy to cross the North Pacific on a passage that took us from Hawaii then north and east &mdash up-and-over &mdash the North Pacific high, with a projected landfall near Icy Strait, in SE Alaska. Our Alaska landfall didn’t work that way, however. Unseasonably intense low-pressure systems and the associated breakdown of the North Pacific high altered our landfall towards the Strait of Juan de Fuca, some 1,000 nautical miles to the south and east of our intended finish, near Icy Strait, at latitude 59 degrees north.

We spent the winter season in Seattle. By the following spring, after making a few modifications for cruising in a colder, wetter, maritime climate, we once again pointed Anna true north, to pick up where we had left off, so that we might spend as much time as possible in SE Alaska, under the relatively favorable weather conditions of late spring and summer. We planned a loop that would give us time to weave through the stark icescapes and wilderness anchorages of the southeast &mdash a 2,500 nautical-mile loop that would resonate with us.

Timing the current
We made the Dixon Entrance, with a lot of luck on our side: we had fortuitous timing at the five rapids we needed to negotiate; plus we experienced fair seas, clear skies and favorable currents. We made the Dixon Entrance in just 11 long-mileage days, after slipping the lines in Seattle. The entrance is precariously located at the confluence of the Gulf of Alaska and Hecate Strait, a volatile and shallow stretch of open water. It is here that the continental shelf of the North Pacific Ocean Basin drops off into deep water &mdash about 6,500 feet &mdash just offshore. The intensity of the ocean swells, strong currents and short, steep wind-waves amplify dangerously when a full gale blows through the area.

There was no doubt that when we crossed the international boundary line, the east-west axis across the center of the Dixon Entrance, we were crossing into both another country and, so it seemed, into another world &mdash a space with complex dynamics and dramatic scale and stunning beauty. These were parameters that could be quantified by the advance and retreat of an aggregation of glaciers, the continuum of unstable weather systems and the increasingly less predictable wildlife migrations and distributions. There was also intense beauty: dense, gem-like blue ice; uncorrupted, raw wildness; the graceful, slow arcing of a humpback’s distinctive tail in fluid motion as it slips away from the surface to dive. We had compelling reasons for visiting the southeast.

With great foresight, almost all of SE Alaska has been set aside as a protected wildlife refuge and remote wilderness. An extensive area comprised of the Tongass National Forest and the Glacier Bay National Park and Preserve &mdash more than 20 million acres of marine and wilderness ecosystems. Most exploration of fjords and glaciers and remote wilderness in this immense, protected area requires an initial approach by floatplane or boat. And, in our opinion, a robust sailboat is perhaps the very best way to get a sensibility for the surroundings.

Back to basics
We spent a lot of time trying to figure out the early warning signs, the indicators of unfavorable weather systems approaching the area. We could not always count on receiving scheduled broadcasts of weather forecasts. In confined, steep, mountainous areas where many of the wilderness anchorages and waterways are located &mdash thousands of feet below the surrounding peaks &mdash VHF and HF-radio signals are completely lost or received as broken static. A sat-phone lock was unreliable unless the orbiting satellite was directly overhead &mdash a position that would last for only a brief period. So, downloading a weatherfax, or a GRIB file, or receiving a clear radio transmission was not always possible.

Ultimately, getting true feedback of sea state, wind direction and wind speed when anchored five miles deep, into a protected inlet, required hauling anchor and heading back to the entrance of the inlet and taking a look-see, at the real-world conditions on the outside, the ocean side. This is, perhaps, the best way to verify your own forecast &mdash your own best, self-educated guess &mdash before deciding whether the conditions are favorable, or not, for moving on.

The inside passages, within SE Alaska, while more protected, are not without their challenges of strong riptides and fast currents &mdash often 7 knots, or more, can be expected in narrow passages where whirlpools and surging current make slack-water timing a critical factor when planning the timing of a particular leg. Short-period, stacked-up wind waves set against strong opposing currents are frequently encountered along fjords or sloping glacial valleys or the contours of long inlets and straits. Strong, downslope and outflow winds can easily stop forward progress and make the ride uncomfortable for small craft.

In anchorages, even in a protected shallow spot with a good bottom (and these are far and few in-between), we needed to set out a lot of chain rode. In SE Alaska many areas have a 25-foot tidal change every six hours. If, for instance, we were anchoring at low tide, in a depth of 10 fathoms (not unusual in the southeast) and wind conditions were moderate (less than 30 knots) and the bottom was good, then to compensate for a tidal fluctuation of 25 feet and still have at least 3:1 scope we had to drop, minimally, 275 feet of chain rode.

At times, our heavy hook needed to break through a patch of thick bull-kelp. This is a situation where we really wanted to get it right the first time around. We needed to get a reliable set that allowed us to sleep comfortably. Even though we have a heavy-duty manual windlass with both high and low gear ratios, it is still a lot of work to pull up that much chain and anchor more than once or twice in a row.

Navigating through icy waters
Once we reached SE Alaska, we slowed the pace down. We had earned ourselves some weather-window days that we could put in the foul-weather bank &mdash no-go days that we would be able to use later when the going got rough, when intense weather systems would wreak havoc with our plans. Notwithstanding the prospect of bad weather, we were excited to be in Alaska so early in the season.

On day 17 of our 91-day loop, we found the ice we were looking for: shimmering, sparkling, stunning blue ice, off the entrance to Holkham Bay, at the southern end of Stephens Passage.

In the higher latitudes, and with the summer equinox approaching, it was possible to navigate up to 22 hours per day, before the brief period of darkness set in. We found that we had enough daylight and twilight to spot drifting logs, drifting ice and sleeping whales drifting at the surface. At night, or on occasions when thick fog banks persisted, we put our radar to work.

South Sawyer Glacier is located at the southeast terminus of Tracy Arm, in Holkham Bay. Tracy Arm is a 22-nautical mile approach, through a steep, granite-walled fjord, with deep glacier-carved valleys cut out of the mountainsides. The passage becomes increasingly more choked with icebergs &mdash intensely blue icebergs &mdash when nearing the towering face of the South Sawyer Glacier.

SE Alaska is located in a maritime climate and tidewater glaciers are strongly influenced by ocean currents. Relatively mild winter temperatures and cool summers, in this area, result in a lot of precipitation in the form of rain, near sea level. Higher up, in the mountains, above the rain forests and glacial valleys, conditions are more severe. Freezing temperatures and heavy snowfall, at altitude, account for the glaciers and ice fields. Older, tightly-packed ice crystals form here. These high-energy ice crystals are prismatic and separate wavelengths of light &mdash the shorter wavelengths of blue light and green light are reflected out, while the longer wavelengths of red, orange, and yellow, at the opposite end of the spectrum are absorbed, invisible. Less dense ice contains more air and diffuses shorter wavelengths and appears white, or even clear.

At lower elevations ice begins to melt, and when more ice melts rather than falls, the glacier stops advancing. At sea level, a tidewater glacier becomes unstable because of the relative warmth and corrosiveness of the saltwater environment. The erosive nature of tides and wave action result in fracturing and then, calving &mdash the explosive breakup and fall of massive chunks of ice into the surrounding waters.

It is estimated that a snowflake that has fallen in the mountains, takes approximately 200 years before it arrives in the form of dense ice at the face of a glacier. At the Grand Pacific Glacier, located at the northwest terminus of Glacier Bay, we saw a stark, otherworldly icescape 35 miles long that overwhelmed all the other glaciers near it. When we viewed the Grand Pacific Glacier from a distance of just one kilometer we could see, as far as the horizon, the icy peaks of its many embedded mountains barely rising up through a river of solid ice. It was enigmatic and stunningly beautiful at the same moment.

In 1794, Capt. George Vancouver of the HMS Discovery described Glacier Bay as “a compact sheet of ice as far as the eye could distinguish.” Glacier Bay appeared then as a mere five-mile indentation in the coastline of Icy Strait.

Today, we are fortunate that we can sail, unobstructed, for 53 nautical miles, from the coastline of Icy Strait, to the receded face of the Grand Pacific Glacier.

Anchoring in the bergs
Anchoring in Tracy Arm is limited by the extreme depth of the water (up to 200 fathoms) within just a few feet from the steep fjord walls. In additon, there is little protection from wind and from drifting ice that moves in unpredictable patterns, showing no concern for the hulls of vessels that occupy their waters. It is definitely risky business setting the hook in an anchorage where ice is free to roam &mdash but, there are places that provide a modest amount of protection in Tracy Arm, as well as in Glacier Bay.

We sometimes heard massive icebergs crack and boom on the other side of the entrance bar to our anchorage. They would make these noises just before breaking up into smaller pieces that would crash into Holkham Bay. On occasion, we could see large icebergs shoot straight up and then flip 180 degrees. Some of this ice managed to find its way in to the anchorage.

The larger chunks of ice scraping and grinding the gravel bottom was our wake up call to monitor their progress towards our hull. A safe position in a small anchorage one minute might be unsafe the next. It was precarious when the ice was on the move. Ice drifts unpredictably and, as luck would have it, Anna met with no harm.

It can be a tense game of chicken, waiting and watching to see what an iceberg will do. A preemptive move like firing up the engine and shifting position a little while still at anchor can be a good decision when an iceberg gets up close and personal.

At Reid Glacier, in the northwest arm of Glacier Bay, one has an excellent opportunity to anchor very intimately just off the face wall of the glacier. The anchorage, in Reid Inlet, is relatively free of drift ice. It is simply magic to be so close to the wall of ice. On a misty night with a bright but diffused moon, with the water mirror-like and the air calm, nothing can be heard except for the occasional sound of a bird skidding across the water and the tide rushing over the nearby gravel beach. One morning, before the winds picked up, we were able to row up to the rocky beach and walk along the shoreline to the face of the glacier. We could step onto the crevassed surface and hear the crackling of the ice. As the morning wore on we felt cold winds. This was air that shot down the adjacent slopes, across the face of the glacier and then over the anchorage. As we walked back to our beached Zodiac, less than a kilometer away from the face, we could see whitecaps quickly building across the water &mdash it was a tough row back to Anna through the rapidly forming waves.

When we finally reached the protection of Anna‘s lee side and stepped up out of the Zodiac and on to the deck, it became obvious that it was time to leave our anchorage at Reid as conditions were deteriorating rapidly. What was a mirror-pond the night before was quickly becoming dangerous. We weighed anchor and shoved off through the narrow entrance. While the entrance was protected from the outside waters by a sand spit, there was no protection from the wind and waves that built inside the anchorage from the direction of the glacier. Just outside the small inlet, conditions calmed down dramatically. This was a typical, localized effect that occurred in Glacier Bay and at other locations where the shape of the terrain could generate fierce downslope winds. Just a few miles away, to the south, we found an inlet with a secure anchorage, set in a less volatile landscape.

Ice-choked passages
We made a second visit, from the anchorage in Holkham Bay, to the head of the South Sawyer Glacier in Tracy Arm. The glacier is about 21 nautical miles into the arm and as we proceeded the ice grew extremely thick; finding a clear channel to take us close to the face of South Sawyer became a challenge. It can be a slow and tedious process of zigging and zagging through the ice to the face of an active, calving tidewater glacier.

Icebergs are dynamic forces &mdash always on the move &mdash they can flip or calve and move enough to close a channel that might have been open just minutes earlier. Crystal-clear ice is difficult to spot amongst the white ice or blue ice, until your propeller is dangerously close. One thing that we tried not to do was use reverse gear, when ice was close to Anna‘s propeller &mdash in reverse the propeller’s vortex can suck ice into its path and destroy the blades &mdash we carried a spare propeller, but happily never had to resort to diving in freezing waters to swap it out.

We were lucky when a heavy, steel-hulled trawler came up from behind us on one occasion, and offered to cut a path through the last mile as we approached the tremendous blue face of the South Sawyer Glacier. We accepted the kind offer. It felt like the U.S. Coast Guard icebreaker Polar Star was personally cutting a path for us, so that the tedious 21 nautical miles, particularly the very last and most ice-choked legs, would not go unrewarded. We got to within less than a mile of the terminus of Tracy Arm where we finally stood off to take in the towering, surreal panorama of South Sawyer and the immensity of the ice field, beyond. We shut down the engine at this point and drifted very slowly in the mild tidal current, between clusters of pack ice, for at least an hour, while we enjoyed a flask of hot coffee in our raw surroundings. We were amazed not only at what we were seeing, but that we were actually able to navigate Anna to this completely ice-choked position in the first place.

It was a four-hour run back to the anchorage before the light of day faded, so we waited for Anna to drift her bow to the correct direction and very slowly we worked our way back out. Visibility was starting to deteriorate; we were getting into thick fog as we approached the last few iceberg-strewn kilometers before making the anchorage. Anna glided cautiously as we used radar to identify the drift ice surrounding her. We noted some rather large targets and clusters of smaller targets, too, on the radar screen. These targets appeared to be standing still &mdash they appeared the way charted islets do as you pass them &mdash yet they were not standing still and they were not islets and they were definitely not charted. Of course, these radar targets were the larger icebergs that we could now see, as they slowly arose out of the fog while we weaved our way through the drifting gauntlet and back to a snug, welcoming anchorage.

By contrast, in Glacier Bay, the approach to the crackling and thunderous calving of enormous Margerie Glacier, in Tarr Inlet, was rather straightforward. Margerie is a stable glacier and there was not too much ice pack to worry about in the approach. Around the corner, one inlet over, the story was quite different; the entrance to Johns Hopkins Inlet was impossible to negotiate &mdash it was completely closed by the heavy ice pack. If Anna had a reinforced steel hull, it would not have helped us to get us any closer to the face of the Johns Hopkins Glacier.

The Johns Hopkins Glacier rises some 250 feet above the waterline and drops some 200 feet below and continues to thicken and advance, currently at a rate of 4,000 feet per year. Glacier Bay National Park and Preserve contains eight major tidewater glaciers and more than 200 smaller, separate glaciers, including: valley glaciers, piedmont glaciers, and hanging glaciers &mdash all of which are impressive.

Closing the loop
Anna took 19 days to cover the same approximate distance, southbound, as she did while traveling northbound. Low-pressure systems were lined up across the N Pacific, intensifying, in the Gulf of Alaska. These were systems that would put gale- to storm-force weather on the bow. All we could do in those circumstances was wait it out &mdash use the weather days we had saved up earlier on and enjoy a more comfortable ride, perhaps two or three days later, in-between aggressive frontal systems.

We wound our way southward, through most of the outer passages along the Pacific side &mdash the west coasts of the outer islands, including: Chichagof, Baranof, Kuiu, Prince of Wales, Dall, and the myriad of smaller islands, many unnamed, sprinkled all along the way and as far as the western approach to the Dixon Entrance. n

Rich Ian-Frese is a former research engineer, and his wife, Catherine, is a kindergarten teacher. A few months after completing their 11,000-nm NE Pacific Ocean loop, they decided to pick up where they left off and extended their adventure with a 2,500-nm side loop to SE Alaska, before returning to Seattle via Alaska’s outside passage.

Climate change and ice melt

New data from the NASA’s Gravity Recovery and Climate Experiment (Grace) show that Greenland’s ice cap is melting much faster than expected. From 2002 to 2006, Greenland lost about 250 cubic kilometers of ice per year. One cubic kilometer is equal to about 264 billion gallons of water. That’s enough melting ice to account for an increase in global sea level of as much as half a millimeter per year. NASA’s Goddard Space Flight Center used Grace to determine that ice losses far surpass ice gains.

The North Pole experienced record losses of sea ice this past summer, too. Preliminary data from NASA satellite imagery shows that the circle of ice surrounding the North Pole is considerably thinner than that seen since scientists have been taking pictures. There is now a slightly less than 50/50 chance that the North Pole will be ice-free at some point within the next decade &mdash the Northwest Passage was recently opened to navigation for the first time in memory.

As for Alaska’s tidewater glaciers: climate scientists note that they are not as hypersensitive to climate change as the ice cap in southeastern Greenland, for instance. As tidewater glaciers in Glacier Bay melt and release their weight from the land, the Earth’s crust elevates &mdash isostatically rebounds &mdash to compensate as sea levels rise. Glacier Bay is somewhat indifferent to the more dramatic effects of climate change seen in the polar regions. The effects of the ocean, and the shape of the surrounding landscape enable these glaciers to advance and retreat in a repeating cycle. Snowfall high in the mountains will increase a tidewater glacier’s mass and force it to advance, moving its underwater foundation forward. The glacier eventually slides off its foundation into deeper water, which causes it to calve more and retreat. When a glacier recedes and stops calving, another advance can begin.

It is a certainty that what you see one day will look different the next; icescapes are in a constant state of very slow motion. In fact, watching the movement, at the face of a tidewater glacier, is not unlike watching an active field of lava. At Volcano National Park, in Hawaii, we watched as molten lava slowly moved from its primeval mountaintop caldera, burned its way across the valley slopes before terminating in cascades of fire and sparks as it fell into the Pacific. After it cools, the land flow becomes a trail of formless metallic blobs of black, silver and gold.

&mdashRich Ian-Frese
By Ocean Navigator