Meryl Streep waves as she arrives at the 84th Academy Awards. (LUCY NICHOLSON/REUTERS)

The two-time Oscar winner, nominated for her portrayal of British Prime Minister Margaret Thatcher, hasn’t won the award since 1983, when she picked up the Best Actress accolade for “Sophie’s Choice” in a similar frock. It seems she’s channeling herself almost 30 years later, in a long-sleeved Oscar-gold gown by Lanvin.

She’s also part of a larger environmental movement among A-list celebrities. Streep is the Green Carpet Challenge’s newest recruit, a contest sponsored by Eco Age, a London-based nonprofit where Livia Firth, wife of Colin Firth, is creative director. Firth started the Green Carpet Challenge three years ago, and has since recruited Viola Davis, Michael Fassbender and her husband (among others) to wear eco-friendly designs on various red carpets. Streep is wearing a custom-made Lanvin gown, the first eco-friendly design ever produced by the French fashion house.

Academy's Choice, Actress Meryl Streep giggles with pleasure after receiving the best actress award for her performance in "Sophies Choice during the 55th Annual Academy Awards in Los Angeles, April 11, 1983. (Anonymous/AP)

View Photo Gallery: Stars float down the red carpet in Los Angeles.

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