Tracy Arm, Southeast Alaska
Until about 12,000 years ago all of Southeast Alaska was covered by ice – tongues of fresh-water glacial ice reaching out from giant Continental ice sheets. The inexorable, ceaseless movement of the ice carved the landscape through which we now travel. Mountain tops covered by the ice were rounded into domes. Depressions in the landscape became deep glacial valleys. U-shaped hanging valleys now show us where tributary glaciers joined the main valley glacier. When the climate warmed and ice retreated the sea rushed in. The flooded glacial valleys became fjords. Tracy Arm, cutting into the mainland of Alaska toward Canada, is one of the most spectacular fjords of Southeast Alaska. Valley walls tower thousands of feet above us, yet they seem so close that we can almost touch them. In places the water under the keel of the Sea Bird is over 1,000 feet deep. Myriad waterfalls descend from snowfields above. Forests cling to improbably steep slopes. As we sailed up Tracy Arm we paused to view a black bear foraging on barnacles and mussels in the intertidal zone. Tracy Arm ends with two tidewater glaciers: the Sawyer and South Sawyer Glaciers. We turned into the South Arm and boarded Zodiacs to maneuver through blue icebergs calved from the vertical ice face of the glacier. Harbor seals like the one seen above dotted the floating ice, using this area to have their pups safe from marauding transient killer whales. The hope is always that the glacier will calve as we watch it. It did not fail us. Several large pieces of ice – each, perhaps, the size of a ten-story building – broke away and fell into the sea with a giant splash and a roar that reached us some seconds later. The waves that they generated rocked our Zodiacs and the Sea Bird, attesting to the immense power of the glaciers in a land called Alaska.
Until about 12,000 years ago all of Southeast Alaska was covered by ice – tongues of fresh-water glacial ice reaching out from giant Continental ice sheets. The inexorable, ceaseless movement of the ice carved the landscape through which we now travel. Mountain tops covered by the ice were rounded into domes. Depressions in the landscape became deep glacial valleys. U-shaped hanging valleys now show us where tributary glaciers joined the main valley glacier. When the climate warmed and ice retreated the sea rushed in. The flooded glacial valleys became fjords. Tracy Arm, cutting into the mainland of Alaska toward Canada, is one of the most spectacular fjords of Southeast Alaska. Valley walls tower thousands of feet above us, yet they seem so close that we can almost touch them. In places the water under the keel of the Sea Bird is over 1,000 feet deep. Myriad waterfalls descend from snowfields above. Forests cling to improbably steep slopes. As we sailed up Tracy Arm we paused to view a black bear foraging on barnacles and mussels in the intertidal zone. Tracy Arm ends with two tidewater glaciers: the Sawyer and South Sawyer Glaciers. We turned into the South Arm and boarded Zodiacs to maneuver through blue icebergs calved from the vertical ice face of the glacier. Harbor seals like the one seen above dotted the floating ice, using this area to have their pups safe from marauding transient killer whales. The hope is always that the glacier will calve as we watch it. It did not fail us. Several large pieces of ice – each, perhaps, the size of a ten-story building – broke away and fell into the sea with a giant splash and a roar that reached us some seconds later. The waves that they generated rocked our Zodiacs and the Sea Bird, attesting to the immense power of the glaciers in a land called Alaska.
