One of the reporters shown in the movie is played by Jackie Purcell, real-life chief meteorologist for KTUU-NBC Channel 2 in Anchorage, Alaska - the station for which Adam Carlson, John Krasinski's character, works in the film.
Much of the footage for the film was shot in and around Anchorage, Alaska. The ice scenes were filmed at Beluga Point south of Anchorage, and several scenes which in the film took place in California were actually shot on location in the Turnagain neighborhood in west Anchorage: plants native to Southern California were used to dress the houses in those scenes. Real Alaska National Guardsmen were used to play the Guardsmen in the film.
When the Green Peace activist dives under the ice in a wetsuit, she has red thermal gloves on. While submerged and using her knife to cut away the net on the baby whale's fluke, her bare hands are visible. When she surfaces, the red gloves are back on again.
Adam Carlson: [Adam sits down across from Jill at a restaurant; looks at the menu]
I usually get the breakfast burrito, which is fantastic... but the pile o' pancakes with a side of ham steak is tempting. What do you think I should get?
No, the Auckland workshops of Glasshammer Visual Effects designed and built a trio of California gray whale puppets that the screenwriters had christened Fred, Wilma and Bamm-Bamm. The whales had a finished look that was as close as possible to the actual 1988 whales, complete with barnacles, scars and more.