ICE AND CONFUSING MAPS
It’s extra hard to do science here because it’s so unknown. Instead of using detailed seafloor maps made by ships cruising through a highly trafficked area, we’re using satellite maps of micro-gravity changes in sea level (bigger mass, like an underwater mountain [which comes up to a shallow depth], means more gravity, just like with planets). The gravity maps are like having a jigsaw puzzle where each piece is a single, average color. But instead of small pieces that let you see the details of the whole picture when you put the averages together, our pieces are too big and we’re missing a lot of details. One time we were in an area the maps said should be 1,200 ft deep, but our instruments measured it at more than 3,000.
There’s also a lot less mud on the bottom than anyone expected. Is it because big ice here scours the seafloor down to the rocks? Or because currents wash the mud off our shallower sampling sites into the really deep areas we’re not studying? Or because the land is so different here (flat instead of mountains like West Antarctica)? Not enough people have studied here, so we don’t know!
Right now we’re also really having a hard time with the increasing ice cover- it’s nearly winter! The last 5 sampling sites all had to be moved multiple times as we tried to reach pre-determined coordinates that were packed in by thick, old ice. And it’s not like it has to be a solid ice sheet to stop us. Even chunks will nudge us around enough that a field of them makes us slow down a lot and work hard to get through- it saves us time and fuel to go around a field like that. Plus we need an ice-free surface to get our instruments in the water. Even small ice pieces are really heavy. The risk of something drifting into our cables and snapping one makes it not worth it to get into big ice even if it was easy.
(The whole ship, scientists and crew, wish that we could get more samples more easily. But when I ask them about it, they tell me it’s all part of learning about a new and unexplored area, and that all data is good data.)
🤷♀️ Virginia
A real-time (not sped up or slowed down) video of us moving through some chunky sea ice. Look how small the first piece of ice is that nudges us, and then look how big the nudge is from the edge of that second piece. Our pilots are amazing! And navigation here is hard!