(REPOST/BLAST FROM THE PAST)
My lips were chapped and I was thirsty. I had joined the others, already up and about on deck, as I often did before reporting to the lab. There was excitement and whispers of awe. We had company. A large berg had drifted into our path while I had slept and hovered only a few boat lengths away. I stepped up to the railing and craned my head, curious to get a better look. We were dwarfed by a gigantic frozen slice of blue Napoleon. It looked just like the layered desert, except there was no pink but so many shades of blue, some common, others less so. We could see every layer of ice and snow that had been deposited over the past tens of thousands of years. Some had left deep blue layers, others just a hint of blue, and some years had left just plain white ice. Somehow the firn had grown with almost none of the bubbles and pockets of air that otherwise caused the light to break and scatter certain wavelengths, allowing for so many shades and layers.
Down here, far from any man-made structures, it is hard to remember that blue is the rarest color in nature. Few things are truly blue. For centuries, toxic cobalt had to be ground to powder to achieve man’s perception of sky and water in numerous paintings.
But on that day, the world was truly blue and on the horizon, a bright, glacial coastline spanned the view, innocent and unspoiled. Above it all, the ultimate blue dome, neither blemished by the appearance of clouds nor bothered by the disruption of sun or moon or stars. We were here at the end of summer and the sun meandered up and down, along the horizon, as if it could not decided whether it was time to cross the sky or to journey on, behind the Earth.
The continual pinging of the SeaBeam reminded me that it was time to head back and start my day. Every few seconds, another chirp was sent straight to the floor of the sea from where part of it bounced off and back our way. An array of sensors, always ready, waited to record the echo. From there the signal was processed, digitized, and converted to depth. I did some more processing on it to removing artifacts and outliers (data that has been corrupted for various reasons but is fairly easy to identify) and finally, I created bathymetric maps: digital dots joined together to form images of the seafloor. In addition to measuring ocean depth, we also collected gravity data. It was part of my job to analyze these gravity signals. A comparison would reveal the history of the seafloor features that we collected with every ping.
Stay tuned for part 2