Ascending

[Nwcid]

While reading different scuba forums I see tons of emphasis on ascending, ascent rates and safety stops. I fully know the importance of all of these things, the points being made on them almost make it sound like the type of diving I do is rare.

Do most people do some form of "square" profile dive where they descend to XX depth then return on a similar path or do most do a "contour" profile? By contour I mean descend in reasonably shallow water to XX depth and then work your way back up slowly back up while following the bottom.

While I understand I am just one type of diver, in my just over 200 dives I have only free ascended from any kind of depth a few times. On most of my dives I am still exploring things at 15' the only thing to do make sure not to go higher. Even from the safety stop I usually don't "surface" until I can stand up and keep my head out of water. My last dive lasted 85 minutes, 45 min was below 20' and the last 40 min was all above 20'.

 

[BRT]

We have the luxury in the PNW of looking at things all the way up, often even from a dive boat. That doesn't work so well hitting a reef or wreck at a fixed depth and eventually having to ascend off of it. I really like the way we do it but it doesn't work well in Puerto Morelos Mexico. In Cozumel you often can work your way up part way.

 

[CuzzA]

Sounds like you're shore diving. I would expect that you would follow the contour of the bottom toward the shore and conveniently that would be your ascent profile.

Where I live there's very little shore diving. We travel 10+ miles to patch reefs, ledges and wrecks. There is no following the contour of the bottom to skinny water. If you're in 100 ft. of water, you're in 100 ft. of water. It ain't getting shallow for a long ways a way.

 

[tbone1004]

If I have the option to shore dive and follow the contours up vs. a square profile I take it, especially if you're doing a decompression dive.... That said most of my diving is in caves, and there aren't really any square profiles in a cave

 

[boulderjohn]

As others have suggested, it all depends upon the characteristics of the site you are diving. A multi-level dive has a lot of benefits, including especially the ability to prolong the dive time while having cool stuff to watch. Sometimes there is no such option. The diving I do in South Florida is mostly of the square profile nature, and there is no way to do it differently.

 

[billt4sf]

I think that a lot of dives require ascents in blue water and it's important to learn how to do them, first with a line off a boat, second with a buddy or group that has done them before, and third using your computer and launching your own SMB.

A pretty important dive skill I would say, and one which typically requires good control of your buoyancy.

- Bill

 

[Dan]

Your dive profile is pretty common for beach entry & exit with gradual slope & shallow diving, not to a ledge of wall diving, which could be fairly deep. Example of this kind of diving is a muck diving in Blue Heron Bridge.

In recreational diving, we typically want to do a V (or a "check mark") type diving profile, where we descend quickly to the deepest part of the dive site & slowly ascend to the shallow to maximize our bottom time. I often check my remaining bottom time at each depth & ascend to the shallower depth to avoid DECO.

Air consumption is not a problem for me using Aluminum 80 cft tank in an quiet, slow or no current sites. Bottom time is the limiting factor. So the V profile will give the maximum bottom time IMHO.

 

[Neilwood]

@Nwcid your diving sounds exactly like the diving I was doing at the weekend. All the dives were similar in that virtually the entire dive was spent following the contours of the shore down and back up with a shortish section in the middle travelling across it.

 

[sea_otter]

It is an important skill to have and practice even if most of your dives are from shore. I went out on a boat trip a while back with a relatively inexperienced buddy. I was also relatively new to my drysuit and cold water diving at the time. He used his air a lot quicker than either of us expected, and he did not tell me when he reached our agreed turn pressure. We weren't able to get back to the anchor line and had to do a free ascent in blue water (or rather... green water).

Between dealing with the drysuit, my buddy having shaky buoyancy control, and limited visibility, this was a LOT harder than I ever would have imagined. We both made it back to the boat safely, but since then I've spent a lot of time practicing things like SMB deployment, free ascents, and air sharing ascents (which fortunately we did not have to do that day). I have also learned my lesson about being absolutely sure that everyone is in full agreement on the gas plan, and I keep an eye on a buddy's bubbles to see if he's breathing more heavily than expected. I'm also a lot more cautious about going out on a boat with a new buddy (it's a very different experience in California than it is in the tropics - now I know).

 

[huxley_knew]

Sounds like you're shore diving. I would expect that you would follow the contour of the bottom toward the shore and conveniently that would be your ascent profile.

Where I live there's very little shore diving. We travel 10+ miles to patch reefs, ledges and wrecks. There is no following the contour of the bottom to skinny water. If you're in 100 ft. of water, you're in 100 ft. of water. It ain't getting shallow for a long ways a way.

Well, it depends. I dive La Jolla Shores more than I'd like to and most of the time we plan our dives out of the canyon (usually 60-70 fsw, but can routinely go to 120+ fsw) such that we swim up out of the canyon and along the sand flats, using it as our safety stop.

That said, if I'm at the Yukon, it's gonna be a long swim back from the bow to a sand-bottom safety stop.