Glaciers are thrilling. Glaciers are Melting McBride Glacier, Glacier Bay. Melting glaciers reveal the effects of glaciation. Why Glaciers?

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1 Glaciers are thrilling Six trips to SE Alaska, most recent 2015 Additional trips up Inside Passage Author of Glaciers, Bears and Totems Glaciers are Melting McBride Glacier, Glacier Bay Why Glaciers? Melting glaciers reveal the effects of glaciation Riggs Glacier, Glacier Bay Empty U shaped valley Glacier Bay

2 Glaciers are fascinating and beautiful Snow becomes a glacier when it is deep enough for its weight to cause it to recrystallize Johns Hopkins Glacier, Glacier Bay Gilman Glacier, Glacier Bay Outline Glaciology and glaciation Location of SE Alaska s glaciers Challenges to boating among glaciers Tour of SE Alaska s glaciers Glacier Bay Kinds of Glaciers: Ice sheets cover whole continents. Ice fields feed multiple glaciers Mountain glaciers resemble rivers of ice in valleys SE Alaska s glaciers are mountain glaciers fed by ice fields. Mountain glaciers ending in the sea are tidewater glaciers Glacier Large mass of ice, older than a year, that starts on land and moves Retreating and Advancing Tidewater Glaciers Retreating: South Sawyer Advancing: Johns Hopkins Sumdum Glacier, Endicott Arm

3 Tidewater glacier cycle Icebergs vs sea ice Icebergs come from glaciers. They are created when a glacier calves. Sea ice is frozen ocean water Web.mit.edu From Earthobservatorynasa.gov Retreating Glacier, Glacier Bay Classification of Icebergs Icebergs: Larger than 10 m (32ft) across. Greater than 5m above surface. Bergy bits: less than 10m across. Between 1 5 m above surface Growlers: less than 6 m (20 ft) across. Less than 1 m above surface Remnant terminal moraines Why are some icebergs blue and others white? Other wavelengths of light are absorbed when they travel through ice Air bubbles make glaciers appear white

4 SE Alaska s Tidewater and Nearshore Glaciers 2007, Baird Glacier, Thomas Bay Holkham Bay Glaciers: Dawes Glacier Sawyer Glacier South Sawyer Glacier Anchorages No Name or Tracy Arm Cove Wood Spit Fords Terror Entering Thomas Bay Baird Glacier, Thomas Bay Baird Glacier Outwash Plain Tracy Arm

5 No Name Cove (aka Tracy Arm Cove) Tracy Arm South Sawyer Glacier Tracy Arm Drifting in Ice Tracy Arm Sawyer Glacier

6 Navigating in new water Sawyer Glacier Dawes Glacier Endicott Arm Dawes Glacier Dawes Glacier, Endicott Arm Fords Terror

7 Wood Spit and Sumdum Glacier Challenges: Calving Keep ¼ mile off glacier face Challenges: Navigating in Ice Challenges: Hazards from Icebergs Navigate around ice, don t try to be an ice breaker! Look for leads. No leads? Drift and wait for leads to open Low visibility in fog Potential to Overturn keep your distance Propellers in Apertures are safest but watch out for low-floating ice. Challenges: Avoiding Seals

8 Glacier Bay Boating Restrictions Glacier Bay s Glaciers West Reid Inlet: Reid Glacier Johns Hopkins Inlet: Johns Hopkins, Gilman, Lamplugh Tarr Inlet: Margerie, Grand Pacific East Muir Inlet: Muir, McBride, Riggs Glacier Bay Permits Application forms at Apply for long notice permits 60 days ahead by after 12:00 am ADT glba_vis@nps.gov Apply for short notice permits 48 hrs ahead by phone after 6:00 am ADT. Glacier Bay is big. Ask for full 7 days. Glacier Bay National Park and Preserve Visit htm for help in planning your visit Download current Fairweather Guide Anchor in Icy Strait the night before Permits start at 12:00 am ADT. May not anchor in GB night before. Anchor at Lemesurier I., Hoonah, Flynn Cove, Pleasant I., or Elfin Cove Confirm w/in 48 hr of arrival date but no later than 10 am of the date or lose permit

9 Glacier Bay not just about glaciers Reid Glacier Glacier Bay through history Pioneer plants 1880 Today Reid Inlet Glacier Bay Willows

10 Reid Inlet 2007 Johns Hopkins Inlet Reid Inlet 1964 Gilman Glacier, 2015 Lamplugh Glacier, 2015 Johns Hopkins Glacier - Advancing Prospector s cabin, 2007 Built ~1940 Reid Inlet Tarr Inlet

11 Tarr Inlet Wildlife in Glacier Bay Margerie Glacier Grand Pacific Glacier Glaciated features Gloomy Knob across from Blue Mouse Cove Erosion of glacial till Wachusett Inlet Gouges & striations, Queens Inlet Melting glaciers are causing land to rise Mountain Goats and Bears on Gloomy Knob

12 Puffins and Sea Lions on South Marble Island Elsie Hulsizer will be signing books after this seminar at Captain s Nautical Supplies, Concourse level Whales and Sea Otters Fairweather Range & Brady Glacier