Have you dived in a Algal Bloom

[andydiver06]

For the past three days we are experiencing some kind of algal bloom here around grande Island Goa. The patch is restricted to about a 1 km x 500 m area. The depth around the site is about 8 m and 4m from top is abolutely clear. Then about 2 m patch have zero visibility. Its orange brown in colour and hanging out like a cloud. Below that again the viz improves to about 4-5 m. Its absolutely fascinating to dive in this condition. You can pull down the algal layer like a cloud to the bottom by waving your hand. It feels like diving in some kind of overhead situation. In some places the clear layer at bottom is only a meter long. The algae is not poisonous as I have been diving there for the past three days. Can anybody tell why only in this selective patch and depth. Next dive site about 1 km away is clear and have an average viz of 4-5 m. Here we are experiencing thermocline . Cold water is coming from depth and you can see the haze where the cold and warm water is mixing like a you see hot air rising in desert heat.

 

[Jon C]

Here in southern California, we get an occasional "red tide" or algea bloom. It actually turns the water a coffee brown/dark red. It is really a gross thing. It smells bad, the vis is nearly 0 and your gear (if you go in it) comes out smelling like dead...well dead something!

The few times I ventured in duing one were always bad and I had this overwhelming desire to take a shower!!!

Yet another quirk here in So Cal.

Jon

 

[Guba]

From late spring to mid fall, ALL the freshwater lakes in North Central Texas experience algal blooms. That's why 6-10 foot vis is the norm for us. Now see why we love to get into the ocean?

 

[KzooJason]

We have a similar problem in Michigan... during the warm summer months our vis drops to levels that would have been disturbing when I started diving. On the bright side, it just makes me appreciate good vis that much more!

Jason

 

[archman]

Thread moved to Marine Life so the science nerds can play with it.

 

[wardric]

anyone ever heard of blue-green algae (cyanobacteria)?

It's a fairly new problem here, the worst part being that it releases a toxin in the water which could be a health hazard to anyone in contact with it, including divers. Some of our nicest lakes could be affected

 

[archman]

What species of blue-green are you referring to, wardric?

 

[CBulla]

We've been getting Red Tide (algae known as K.brevis) consistantly for 6 years now... horrible thing to be around, sounds similar to what your describing only you've not mentioned wild life death from it.

We've also got a grassy algae that blooms and until it hits the beach and smells like a septic treatment center gone bad, it provides a unique grassy looking dive full of little fishes.

 

[TeddyDiver]

anyone ever heard of blue-green algae (cyanobacteria)?

It's a fairly new problem here, the worst part being that it releases a toxin in the water which could be a health hazard to anyone in contact with it, including divers. Some of our nicest lakes could be affected

It's also a severe problem in the Baltic, but I don't have any experience there.
In the Arctic Ocean (Barentz Sea), where I mostly dive, there's two algael blooms a year. 1st one in late april/early may green algae blooming from the surface to about 80' (big green "snow flakes" like it's snowing). 2nd one starts in late july above the depth of the thermocline. Starting near the surface descending deeper along the warming water temperature. Viz can be only 8'' in the algae layer, and beneath it 30' to 100'.

 

[Ron Brandt]

Lake here was really bad this year..knocks the vis down to Zero

Ron