This weekend was fun. We did a bunch of scuba dives and a little snorkelling as well. This was part of a scuba diving course taught by National Aquatic Service on our university campus. The basics of diving were taught in a swimming pool in our school, and this weekend was in Lake Skaneatles - it is also the fresh water source of Syracuse.
The water was crystal clear, and we could see 10-20ft, except for when we newbies were kicking up the silt from the lake bed due to poor buoyancy control and could see nothing! Here's a pic of our dive site.
A summary of what I've learnt so far - Most of diving is fun, although setting up the equipment is a long and tedious process - there's (i) wearing the dry suit for cold weather (a Syracuse signature :)) (ii) setting up the buoyancy compensator (BC) (iii) setting up the cylinder of compressed air, (iv) cleaning the mask with the solutions so that it doesn't fog, (v) Even putting the fins on can be a bit of a hassle (vi) making the necessary air supply connections to the BC, and of course, the primary air source for us to breathe! Since tightness of connections is important and land does not provide the flexibility that water does, it can get to be quite a process especially when it's cold outside and your fingers aren't working so well :)
A little fish has all these systems built in, and here is man, with all his intelligence, struggling hard to spend a few minutes like a fish! Humbling, eh? :)
Continuing with what I've recently learnt - Things to keep track of while underwater include increases in pressure by 1atm per 33ft, air supply getting lower which requires monitoring. Then there's the nitrogen absorption rates which matter, they are known to cause "bends" if rate of nitrogen release is not right, hence ascent is supposed to be always a slow process. Residual nitrogen amounts based upon depth and duration of dives also govern when, how long and how deep our next dives can be, although it was not quite a concern at these low depths and low dive durations. Also, our eyes are not adapted to look in the water, so the mask is essential. Water could get into the mask, hence the mask has be made such that there is a process to clear it. Light appears different since different colours are absorbed at different levels. There's many others to keep in mind - with regards to air supply, somebody else needing assistance, etc.
Again, a little fish...
When I was under, I could see a few fish (I'm told they were bass/trout) and they seemed unconcerned about us and did not flee as I'd thought they would. Seemed like friendly fellows :)
I must admit, I was a bit apprehensive about going so deep ("so deep" is relative - perhaps this wasn't nearly as deep as professional divers go, but it was by far the deepest I had ever been, the previous being 16ft in a swimming pool). To me it's still a new and unknown world. Everything we take for granted on land, starting from the basic process of breathing, does not come for free in the water. OK fine, it's not quite "free" on land either but that's a different subject for another day!
One of the primary reasons for sticking to shallow waters is that pressure increases rapidly, and the human body is not quite adapted for this. But at about 35-40 feet (the maximum depth of our dives this weekend), with 2 atmospheres of pressure, it was perhaps the mermaids of the deep giving us a warm hug - welcoming us visitors into their world!