Oooh, I can easily recommend {Naked Edge by Pamela Clare} - MMC is an adrenaline junkie (rock climbing, alpine climbing, ice climbing, you name it) and a Park Ranger - he spent the past 3 years doing crazier and riskier climbs (as kind of a professional? I don't remember exactly) and still climbs in his spare time. FMC is a Navajo journalist and member of an elite investigative journalism team - she is deeply rooted in her culture and heritage and focuses on environmental journalism.

It's an RS and one of the most emotionally intense romances I've read - Pamela Clare (who I believe was an award-winning journalist herself) does exceptional research and is amazingly skilled at incorporating said research and sensitivity into her books without info-dumping or being lecture-y. Excellent balance between the romance and the suspenseful action, which many authors fail to do well IMO.

The rock climbing definitely plays a role in many key moments of the book.