Which lens filters are recommended for the Nikon 24-70mm f/2.8?

Adding my two cents here because I had a nightmare experience with a stuck filter a few years back on a trip to the Oregon coast. I was using a cheaper aluminum-framed filter, and the salt spray combined with the cold air basically cold-welded the threads to my lens. I had to use a rubber strap wrench to get it off when I got home, and I almost wrecked the zoom mechanism. Since you are heading to Iceland, here are a few things to keep in mind:

• Brass vs Aluminum: The B+W 82mm XS-Pro Clear MRC Nano 007 uses brass for the ring. Brass is much softer than the aluminum on your Nikon lens threads, meaning it won't bind or seize up when the temperature drops. Hoya uses aluminum, which is way more prone to sticking.
• Cleaning in the field: Iceland has constant mist and sea spray. The MRC Nano coating on the B+W is like magic for shedding water droplets. You can just wipe it with a microfiber cloth and it doesn't streak. Some of my Hoyas tend to smear grease around when I try to clean them in a hurry.
• Alternative budget option: If you want to save a few bucks but still want easy cleaning, look at the Marumi 82mm EXUS Lens Protect. It has an antistatic coating that is great for keeping dust off, and it usually runs a bit cheaper than the B+W. Whatever you choose, just make sure to get a filter wrench to pack in your bag just in case. You do not want to be stranded with a stuck, scratched filter in the middle of a shoot.

Iceland can be pretty brutal on gear, honestly. I have shot there a few times and the wind-blown black sand is absolute murder on front elements if you arent careful. Since you are choosing between a clear protection filter and a UV, I wanted to ask a couple of quick questions first to make sure you get the right setup for the trip. Are you planning to shoot mostly during the day near the waterfalls where mist is a constant battle, or are you aiming for longer exposures where you might want to consider stacking filters like NDs later? Also, is your main concern physical impact protection from drops, or are you more worried about sealing the lens against the harsh environment like salt spray and abrasive dust? Depending on what you are actually facing out there, one of those glass types might be much easier to clean in the field than the other, which is a massive deal when your fingers are freezing. Let me know what your shooting conditions are gonna look like so we can figure this out.