"I've never been rescued before, and I didn't want to be. There's this feeling of 'I can handle this'.
"But there's been a lot of deaths in the past year - we didn't want to be the next ones."
Approaching the summit about 9am, the pair found themselves in wet, deep, "very avalanchey" snow.
After deciding to turn around, they found the conditions on their descent to be even more treacherous.
"Then we had two choices, get a helicopter and get rescued, or stay overnight and bivvy up there and wait for the freeze."
With the wind rising and bad weather threatening in the west, climbing down the exposed ridge the next morning seemed untenable. After being unable to contact the helicopter company by phone or radio, he managed to connect a 111 call about 9.30am.
Mr Karnik said he wanted to be transferred to the helicopter company - "we were fully prepared to pay for it" - but the operator ended up activating a rescue by the Aoraki Mt Cook Rescue Team and Mt Cook Alpine Guides staff.
In hindsight, he realised the operator had to follow a set procedure for such a call.
After being taken to Mt Cook village, the pair arranged to be flown back to Marcel Col - at their own expense - to collect their gear and walk out.
Mr Karnik said that if they attempted Mt Tasman again, they would probably do so during summer, when snow conditions were more stable, and would start their climb earlier in the morning.
They would take a break from ice climbing "for a while", and focus on rock climbing over the next few months.