Glaciers have shaped Alaska's landscape for thousands of years, modifying its mountain ranges and coastline dramatically. And this process is by no means at an end; Alaska has over 5,000 glaciers, many of which are still actively carving the face of the Great Land.
There are basically two types of glaciers: ice sheets and alpine glaciers. Ice sheets are of continental proportions; Greenland and Antarctica are the only two places where ice sheets exist today. The rest of the world's glaciers, including those in Alaska, are alpine glaciers, occupying existing stream valleys in high mountain ranges.
Alpine glaciers form when snow accumulates in a depression within a mountain range; the snow is compacted at the bottom of the mass, becoming glacial ice, and eventually gravity begins to pull the glacier down the mountain. The glacier takes the path of least resistance, following an existing stream bed toward sea level. As it slides downhill, it carves this valley even deeper.
Some of Alaska's glaciers reach the sea; the faces of these tidewater glaciers then drop masses of ice into the water, a process called calving. A tidewater glacier is in perpetual motion, and though the ice mass itself pushes constantly forward, the glacier is said to advance or retreat, depending on the relative movement of its face. If a glacier accumulates more ice at its upper end than it loses to calving and melting at its terminus, it will advance - the face will move continually farther out into the sea. Less accumulation at a glacier's origin or changes in the conditions at sea level may cause it to retreat, its face receding through the valley.
Cruise ship passengers often have the opportunity to view these vast rivers of ice from a unique perspective - head on. The following sections provide interesting information about some of the glacial wonders you might see on your Alaska cruise.
Magnificent Glacier Bay National Park and Preserve, once called Thunder Bay because of the roaring sounds made by falling ice, is the result of glacial retreat. Situated about 90 miles northwest of Juneau, this grand collection of tidewater glaciers is a wondrous blue ice land that encompasses 3.3 million acres. The waterways provide access to some 16 of these glaciers, a dozen of which actively calve icebergs into the bay.
In addition to the jagged icebergs, saltwater beaches with protected coves, numerous freshwater lakes and lush forests of western hemlock and Sitka spruce are all part of this park. It's also a land comprising three climatic zones and seven different ecosystems supporting an amazing variety of animal life: humpback whales, Arctic peregrine falcons, common harbor seals, black and brown bears, marmots, eagles and mountain goats, among many others.
Glacier Bay was barely a dent in an icy shoreline when the English explorer George Vancouver passed by nearly 200 years ago. At that time, what is now the bay was filled with a wall of ice extending more than 100 miles to the St. Elias Mountain Range. The face of the glacier spanned over 20 miles, and in places it was more than 4,000 feet deep. Over the next 100 years, a warming trend that continues to this day created this winter wonderland, which includes some 50 miles of fjords, islands and inlets.
Man's habitation of the Glacier Bay region dates back approximately 10,000 years, but it appears that early settlers didn't stay here for very long. As you can imagine, making a home around Glacier Bay was not easy. Tlingit folklore includes tales of periodic village destruction from shock waves and other natural forces.
European exploration of Glacier Bay began in 1741, when Russian ships of the Bering Expedition sailed the region's outer coast. But it wasn't until famed naturalist John Muir came to this icy wilderness in 1879 to explore its flora and fauna that scientific investigation and early tourism were spurred.
Before long, there were steamship excursions into Glacier Bay, and travelers were taking home adventure tales and photographs. The flock of curious scientists and tourists halted abruptly, however, when on September 10, 1899, a violent earthquake struck the area. This caused enormous slabs of ice from the Muir Glacier to calve, thereby choking the waterway.
When tour ships could no longer sail closer than five or seven miles to the popular Muir Glacier, excursions to Glacier Bay ceased. Tourism didn't develop again until 1925, when Glacier Bay National Monument was established.
Today, Glacier Bay National Park and Preserve continues to attract nature lovers, wildlife enthusiasts and fishermen. And it's a special delight for bird-watchers: more than 200 species of birds have been recorded in the park. In the mouth of Glacier Bay, as well as in Sitakaday Narrows and Adams and Hugh Miller inlets, the tidal flow is concentrated in narrow or shallow portions of the bay, where the resulting water turbulence stirs plankton, shrimp and fish to the surface. Large flocks of sea gulls and other shorebirds gather here in feeding frenzies. Small islands, where no animals live, are favored nesting sites of tufted and horned puffins, ocean cormorants, glaucous-winged and herring gulls and black oystercatchers.
Hubbard GlacierThe mighty Hubbard Glacier flows over 90 miles through the Wrangell-St. Elias National Park and Preserve to Disenchantment Bay, the head of Yakutat Bay. While at present the Columbia is retreating, the Hubbard is advancing, as it has for more than 100 years.
In 1986, the Hubbard began a surge, a period of rapid glacial advancement, which reached a dramatic climax before the end of the year. By springtime, the glacier had completely blocked off Russell Fjord from the sea, creating a rapidly rising freshwater lake.
Local residents feared flooding in the surrounding area; scientists and environmentalists were also concerned for the lives of the marine mammals trapped in the lake. Volunteers succeeded in rescuing a few seals, and several others crossed the ice dam themselves, a distance of about a quarter of a mile.
The remaining animals were released when the dam gave way on October 8, 1986. A flood of ice, water and debris crashed into Disenchantment Bay in a thunderous spectacle that lasted for hours. Despite the fact that water rushed into the ocean at the estimated rate of 3.5 million cubic feet per second, no serious flooding occurred.
The Ice-Carved CoastGlacial retreat is responsible for the spectacular fjords of Alaska's coastline, steep-walled inlets carved by previous glaciers. This geological phenomenon has produced some breathtaking landscapes.
Misty Fjords National MonumentTowering mountains, cascading waterfalls, lush green forests and magnificent glaciers make Misty Fjords National Monument one of America's outstanding scenic wonders. Located in southeastern Alaska's wilderness area, the over-2.2-million-acre region is also known for its wildlife, white sandy beaches and unique ecosystems. Excursion boats enter Misty Fjords through the Behm Canal, a 100-mile-long narrow inlet of the northeastern Pacific Ocean.
Misty Fjords is named for the almost-continuous drizzle typical of southeastern Alaska's rain forests. Each year, three major rivers and hundreds of small streams are fed by more than 150 inches of rain and snow, as well as by meltwater from large ice fields and glaciers originating near the Canadian border.
Misty Fjords National Monument is a part of the Tongass National Forest. The first of Alaska's 18 national monuments, its rugged terrain supports many nearly untouched coastal ecosystems. Sitka spruce, western hemlock and cedar trees flourish in the moist climate. Alder and dense underbrush grow in places as high as the timberline - about 2,000 feet above sea level - and lovely alpine meadows are nestled in mountain valleys.
The unsettled backcountry is home to the state's famous brown and black bears, Sitka black-tailed deer, wolves, mountain goats, beavers, otters and foxes. During the summer, pairs of bald eagles soar above the nearby rivers and shorelines in search of fish. Freshwater trout and five kinds of salmon are the commonest fish. In the Behm Canal and nearby ocean waters, porpoises, whales, sea lions and seals are occasionally spotted.
Active glaciers on the northern and eastern boundaries of the area date back to an ice age of thousands of years ago. As recently as 1920, volcanic lava flows occurred near the northern boundaries. Mineral springs are another distinctive geological feature of the region, and veins of gold, silver, copper and other minerals may be found in mountains that rise as high as Mount John Jay, at 7,499 feet.
The appeal of Misty Fjords could be attributed to the absence of human activity. Traces of the first human inhabitants reveal that as early as 10,000 years ago Tlingit and Haida societies settled here, and evidence of early American occupation may be found in a few places. However, today the area is uninhabited and retains its primitive beauty.
Other FjordsCollege Fjord is a 20-mile-long inlet located within the boundaries of the Chugach National Forest near Columbia Glacier. You'll have a chance to witness the action of numerous glaciers - some are always calving - while sailing through this fjord.
Tracy Arm, south of Juneau in Alaska's Panhandle, is another visual delight - sheer cliffs rising 3,500 feet from the sea, imposing tidewater glaciers, abundant wildlife and other thrilling sights around every curve of this narrow, winding inlet.
During the late 1800s, explorers to this area survived courageous trips through the rapid waters in small boats and canoes. In 1889, a survey team led by Lieutenant Commander H. B. Mansfield named the now-preserved wilderness Ford's Terror. Once the explorers made the trip up the rapids, they saw a world that had undergone few changes since the last ice age. Tracy Arm - Ford's Terror - is one of several remote locales preserved as a national park, monument and wilderness area. Within its 656,000 acres of undeveloped terrain, you'll see varied sea and bird life as well as brown and black bears, goats and eagles.
As your ship cruises through the scenic 22-mile-long fjord skirting the Tracy Arm - Ford's Terror Wilderness Area, you will first have a chance to watch Twin Sawyer Glacier calving, as massive chunks of ice break and plunge into the ocean. You'll also see South Sawyer Glacier, where seals often cavort on the ice in front of the glaciers. The ice serves to protect young pups from killer whales, and the area provides an excellent food supply for the animals.
Endicott Arm is another perfect example of the natural wonders of Alaska's Panhandle, considered by many the most beautiful area of this grand state. The terrain of this region is very different from the main body of Alaska. The southeast is made up largely of the hundreds of islands of the Alexander Archipelago and a narrow coastal strip of mainland from the crest of the Coast Mountains to the sea. Waterways bind the mountainous, thickly forested islands and the sliver of mainland together.
John Muir, who canoed through Alaska in 1897, wrote about his journey as follows:
We found ourselves on a smooth mirror reach between granite walls of the very wildest and most exciting description, surpassing in some ways those of the far-famed Yosemite Valley.
His words could have been written just yesterday.
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