Kate Upton: Price I Paid to Be on SI Cover

Kate Upton visits CNBC to talk about being the two-time cover girl for Sports Illustrated Swimsuit edition.
Adam Jeffery | CNBC

Two-time Sports Illustrated Swimsuit cover model Kate Upton has yet to reach her 21st birthday and may already be a household name.

Upton, who turns 21 in June, has now graced the cover in back-to-back years: in 2012 as Sport Illustrated Swimsuit's Rookie of the Year and again in 2013 with a photo from the first ever fashion shoot in Antarctica.

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"It was an adventure for sure," Upton told CNBC in-studio Tuesday. "It's freezing there, obviously. No one knew what to expect. You had to go the land in these zodiac boats, kicking ice just to get the rafts through."

Upton, who hails from Florida, said she experienced hearing and eyesight loss after returning from the Earth's southernmost continent. "If I didn't get sick standing in Antarctica in a bikini, something would be wrong with me. I'd probably be Wonder Woman or something."

Swimsuit Model's Very Cold Photo Shoot

The model has Sports Illustrated to thank for propelling her into superhero status in 2012.

"Everything's changed," she said, reflecting back a year. "I have so many opportunities now with different clients and I think for me what's really exciting is now I get to choose which clients I work with, so I can do products or shoots that I really love and I really believe in."

Upton, with more than 1.1 million combined followers on Twitter and Facebook, is undoubtedly loved by fans across the world. "We can finally talk about Antarctica!!!!!" Upton tweeted when Sports Illustrated officially revealed the news. "Took us 2 months to thaw out."

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How big is the Sports Illustrated Swimsuit business to Time?

"It's 10 percent of our overall business on a yearly basis," said Time Sports Group President Mark Ford. "Since '64, it's generated a billion dollars in revenue for us."

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Sports Illustrated estimates 62 million people will flip through the pages of this year's issue.