Back to Category » Science Reports

How to drive an underwater sports car in reverse?

Posted on July 7th, 2009 by Allyson Brady

Tuesday was my first DeepWorker dive of the season. It was so great being back in the sub! I had almost forgotten how much fun it is to pilot and how amazing this lake is. The objective of my dive was to document transitions in the microbialites as you moved from deeper depths up slope to shallower depths and then back down again. We really want to get an understanding of how the microbialites vary within the lake and what types of lake characteristics (e.g. steepness of slope, sedimentation) might be associated with particular morphologies. This was a new type of dive as compared to the types we had planned last year and I wasn’t initially sure how easy it would be to back down the slope. Going up slope worked quite well, once I was back in pilot mode, remembering how best to combine my foot movements in order to minimize sediment disturbance.

It was really fascinating seeing how the microbialites change as you move into shallower water. You could really see that there were differences in the morphology as you changed depths. Transitions from columnar, smooth surface microbialites to rough, nodular looking ones were common. I also saw some huge microbialite mounds and microbialites growing on rocks and trees, very interesting for answering some of our science questions. Loads of algae were also visible in the shallower depths, everything from bright green filamentous algae to dark green material that resembles shag carpeting.

Screen Capture from the science stenographer showing Allyson's dive track on a map of the south basin in Pavilion Lake.

Screen Capture from the science stenographer showing Allyson's dive track on a map of the south basin in Pavilion Lake.

Once I was within 10 feet of the surface, the next objective was to move down slope along the same pathway capturing detailed video of the area. Hmmm…how do you back up the equivalent of a floating sports car with no rear view mirrors? As it turns out, very slowly and carefully actually does the job! After a few attempts, I think I was starting to get the hang of it and managed to get some quite nice video footage backing down the slope. It took a bit of practice but we’re all here to learn and that includes not just learning about the science, but learning about how best to explore our environment and collect the data that we use to answer our questions. At least I didn’t have to parallel park.

-Allyson

2 Responses to “How to drive an underwater sports car in reverse?”

  1. Liz Foster says:

    Fantastic and exciting! Thank you for the look over your shoulder as you’re exploring. I love seeing my taxes spent on research. Any thoughts on the effects of short- and long-term variations in water level on the morphology of the bioherms?

  2. Allyson Brady says:

    Glad you enjoyed it Liz! Great question, we are very interested in any physical, chemical or biological changes that might occurred recently or in the past including lake water level changes. Certainly more shallow regions such as the bioherms could have been exposed at one point if water levels were lower and this may have influenced the development of the microbialites. The challenge is in trying to separate out the effects of individual parameters such as water level from others such as light or temperature changes. The mapping of microbialite morphologies with DeepWorker should help us to answer some of these questions.