Today, we went out onto the North Sea for a day of maritime training, a course how to rescue, survive and help in the case of being lost at sea, or going overboard from a ship at high sea. The course was extremely valuable towards my long-term goal of being able to do clean-ups of North Sea shipwrecks from ghost nets, abandoned fishing nets which harm marine life.
We went out this morning for two hours of class-room training and then boarded a ship and went out to sea, where we learned how to use flares, smoking pots, floats and various means to rescue men over board and victims of drowning.
This training was organized by Get Wet. I can highly recommend it.
I’ve been trying macro photography and using the depth of field to make the subject of my photos stand out more from the background. This photo of a parrotfish shows promising results beyond “blurry fish butt” quality. I’ll definitely use this technique more often in the future, especially for colorful fish with colorful coral in the background.
As a founding member of our surf club, I’ve decided to do what what was long overdue and took my second surfing lesson.
I went to a surfschool in Scheveningen at the North Sea, got in touch with an instructor, and after going over the water situation, currents, swell and technique, we went into the water for a good one and a half hours. There was a good swell, and next to the harbour’s pier, we were mostly out of the wind. After building up some skills, like catching waves and paddling into them, I managed to ride out a few waves, onto the beach. Not over a long distance, but at least I didn’t fall for a few seconds, a few times. Pretty good progress. Next try planned on sunday, weather allowing. It’s still the North Sea, and it’s still winter, so things can get nasty…
The water temperature was 9°C, which seems cold. I wore my 7mm full-length suit, 3mm gloves and a 5mm hood. It didn’t feel cold even in my fingertops after getting out of the water, so even in March, the North Sea is already very manageable.
Surfing was great fun, it’s an interesting break from diving in that it’s much more physically active. In diving, you tend to spend as little energy on anything as possible. That means that if you’re a good diver (and in the right conditions), you actually burn very little energy. That means you’re getting cold much quicker. Bodysurfing, on the other hand means that you’re constantly moving through the swell, swimming, paddling, getting up, falling, so you end up burning a lot of energy. The cold splash of water is really welcome then.
As opposed to diving, there is no buddy system in surfing, so you can go surfing on your own (under the right conditions, of course). That makes it a bit more flexible than diving. It also trains different muscle groups, especially arms and shoulders, so it complements diving well.
I’ve always loved diving down while snorkeling or swimming, and it’s been intriguing to me how long I can hold my breath, how far and deep I could go just like that. (The answer so far, 14m.)
Last week, I met with Jeanine Grasmeijer. Jeanine is one of the world’s top freedivers, two times world record holder, 11 times Dutch national record holder. She can hold her breath for longer than 7 minutes. Just last month she dove down to -92m without fins. (For the mathematically challenged, that’s 6.6 times 14m.)
Jeanine showed me how to not breathe properly.
We started with relaxation and breathing exercises on dry land. Deep relaxation, breathing using the proper and most effective technique, then holding breath and recovering.
In the water, this actually got a bit easier. Water has better pressure characteristics on the lungs, and the mammalian diving reflex helps shutting off the air ways, leading to a yet more efficient breath hold. A cycle starts with breathing in the water through the snorkel for a few minutes, focusing on a calm and regular, relaxed breathing rhythm. After a few cycles of static apnea (breath holding under water, no movement), I passed the three-minute-mark at 3:10.
We then moved on to dynamic apnea (swimming a horizontal distance under water on one breath). Jeanine did a careful weight check with me, making sure my position would need as little as possible correction movements while swimming. With a reasonable trim achieved, I swam some 50m, though we mainly focused not on distance, but on technique of finning, arms usage and horizontal trim.
The final exercise in the pool was about diving safety. We went over the procedure to surface an unconscious diver, and get her back to her senses.
Freediving, as it turns out, is a way to put the world around on pause for a moment. You exist in the here and now, as if the past and future do not exist. The mind is in a completely calm state, while your body floats in a world of weightless balance. As much as diving is a physical activity, it can be a way to enter a state of Zen in the under water world.
Jeanine has not only been a kind, patient and reassuring mentor to me, but opened the door to a world which has always fascinated and intrigued me. A huge, warm thanks for so much inspiration of this deep passion!
In other news on the “mammals that can hold their breath really well” topic: I’ve adopted a cute tiny orphaned whale!
The Ocean Warrior, the newest vessel in Sea Shepherd‘s fleet docked in Amsterdam before beginning its voyage to the Southern Ocean around Antarctica to prevent poachers from killing whales. Sea Shepherd is a marine conservation society that employs direct action to protect marine wildlife. The Ocean Warrior is a 54m custom-built vessel, hosting a crew of 16. It’s very fast, reaching almost 30 knots at top speed. It is powered by 4 3000 horse power engines, and features an open deck at the stern with a hefty water cannon.
The Ocean Warrior is an incredibly slick and strictly functional master-piece of ship engineering. Its solid build makes it a tool suitable for the extreme conditions around Antarctica.
Its unusually high top-speed will give the Sea Shepherd fleet a huge strategic advantage in the vast wideness of the Southern Ocean.
Marco has come over to the Netherlands to pay me a visit, and to hack a little bit together, in person. So with the weather clearly suggesting to stay inside, that’s what we did over the weekend, and how better to entertain yourself than to work on mobile software?
Marco has been working for a while on components that follow Plasma’s human interface guidelines and make it easy to implement applications with a common navigation pattern and look and feel. Obviously, these components use a lot of Plasma under the hood, so they get excellent integration at a visual and at a technical level. This high integration, however, comes at the price of having a non-trivial chain of dependencies. That’s not a problem in Plasma Mobile, or other Plasma workspaces, since all that is already there, anyway.
We thought that an interesting exercise would be to find out what really defines a “Plasma application”, and how we can make the concepts we engrained in their design available to application developers more easily. How hard could it be to use Plasma components in an Android app, for example? The answer is, not entirely trivial, but it just became a whole lot easier. So what did we do?
For those reading this article via a feed aggregator, hop over to youtube to watch the demo video.
We took Subsurface, which is a piece of Free software used for logging and analysing scuba dives. Subsurface has a mobile version, which is still in its infancy, so it’s an excellent candidate to experiment with. We also took Marco’s set of Plasma components that provide a reduced set of functionality, in fact, just enough to create what most applications will need. These components extend QtQuick components where we found them lacking. They’re very light weight, carry no dependencies other than QtQuick, and they’re entirely written in QML, so basically, you add a bunch of QML files to your app and concentrate on what makes your app great, not on overall navigation components or re-implementing for the n-th time a set of widgets.
So after solving some deployment issues, on Saturday night, we had the Plasma mobile components loading in an Android app. A first success. Running the app did show a number of problems, however, so we spent most of the Sunday to look into each problem one by one and trying to solve them. By early Monday morning, we had all of the glaring issues we found during our testing solved, and we got Subsurface mobile to a pretty solid appearance (pretty solid given its early state of development, not bug free by any means).
So, what to take a away from this? In a reduced form, Plasma can be a huge help to create also Android applications. The mobile components which we’re developing with Plasma Mobile as target in mind have had their first real world exposure and a lot of fixes, we got very useful feedback from the Subsurface community which we’re directly feeding back into our components.
A big thanks goes out to the Subsurface team and especially Dirk Hohndel for giving us excellent and timely feedback, for being open to our ideas and for willing to play guinea pig for the Plasma HIG and our components. The state you can see in the above video has already been reviewed and merged into Subsurface’s master tree, so divers around the world will be able to enjoy it when the app becomes available for a wider audience.
I recently went on a vacation to Cuba. As I wanted to go scuba diving there, I researched a bit beforehand. The information I could dig up was spotty at times, so I decided to share my notes in order to add it as anecdotal information when planning their diving trips.
During the 3 week trip to Cuba, I visited three locations in the south-western part of the island. In total, I did 19 dives along the Cuba coast, all of them very enjoyable. On the list were shallow (10-18m) coral reef dives, wall dives, some of them deep. I clocked my max depth at 34.1m. One of the things I wanted to do was a cave dive in a Cenote. Cenotes are underwater cave systems found around the geological area.
Cuba, being a Carribean island has a tropical climate with warm waters around it, and climatically a wet and a dry season. As the wet season may make the sea choppy, reduce visibility and carries the risk of hurricanes, it’s advisable to pick the dry seasons, months from November to May for diving activities. The South coast, which is where I have been diving had warm waters 27°C at the surface, and 26°C as depths down to about 35m. Visibility was generally excellent, commonly around 30m, with sometimes up to 50-60m in calm water. In several spots, there are large and well-preserved coral reefs. The South coast usually has calmer waters than the North coast, so I picked locations in the South-West: Maria La Gorda at the far southwestern point of the island, Playa Girón at the Bay of Pigs, and Playa Ancón near Trinidad. All turned out to be worth visiting and made for some amazing dives. (We also visited Cayo Levisa on Cuba’s Northern shore, which has a nice beach, but was mediocre at best for snorkeling from the shore. Go to Cayo Jutia instead, if you want good snorkeling, or book the boat to go diving at Cayo Levisa.)
Cuba is a communist country, instead of Coca Cola advertisements you’ll find some billboard reminding you that “the revolution is invincible”. Economic trade embargoes make acquiring scuba diving gear a problem (although I haven’t seen any shortcomings in this area myself). There’s usually just one dive center running the diving operations, so not much choice, but on the other hand, you’ll rarely encounter crowded dive sites, or reduced visibility due to other divers silting up the waters.
Touristic activities such as diving are usually possible through government-owned dive centers. There’s a network of official travel agents across the country, which can help you with booking trips and getting in contact with dive centers. Many of them are not easily reachable by phone, but you can sometimes book in advance of your trip online. In my experience, it would have been fine to just show up at the dive center at the right time of the day with your certification card and dive logs to prove your experience, and you’ll be almost good to go. I decided to bring my own gear, regulator, jacket BCD, 3mm wetsuit, fins, mask and torch in order to avoid any annoyances or unsafe situations due to flaky equipment.
My personal experience has been very positive, I loved the different dive sites, guides were generally skilled, and I had a whole bunch of amazing dives in Cuba. Would recommend.
Maria la Gorda
Maria la Gorda is a bit off the beaten path in Cuba, one of the more remote locations on the main land. We travelled there from Vinales in 3 hours by car. The location itself is comprised of a hotel, two restaurants, and dive centre on a beautiful beach that also makes for some very nice snorkeling, you can basically walk in and enjoy lots of fish, even those not often discovered while scuba diving. Kim spotted barracuda, jacks, parrot fish, a moray and even an octopus just a few meters off the beach.
Diving there is done by boat 3 times a day. Almost all of the diving spots are within a 15min boat ride. The dive boat goes to 3 different sites a day, at 8:30, 11:00 and 15:00. It’s possible to also do a night dive, but has to be arranged with the staff. If you’re doing a day trip from Vinales just for diving, you’ll arrive in time to do two dives before leaving, the dive center does consider day guests. The surface time in between was enough to not dip too deep into nitrogen levels with 3 daily dives, the first two of them deep. Dives are usually limited to 45′ bottom time. If in general, you can’t get enough of scuba diving, that’s a lot of diving there.
The sites I’ve visited were all amazing in their own rights. Beautiful walls littered with coral, dropping down to 2000m right below you, really nice tunnels to dive through, large fan corals, barrel sponges of 3m and more, large groupers, jacks, and the usual variety of coral reef fish (parrot, box fish, angelfish, jacks, butterfly fish, etc.). Fish of more than 50cm in size were no exception, which seems like a sign that at least this part of the Carribean is comparably less overfished than other areas, there and especially in Asian countries.
The procedures on the boat were a bit unclear, I had liked to get better introduction there. Other people were happy to help, so this wasn’t much of a problem. The guides’ briefings were too short for my taste, especially knowing a bit about the navigation planned underwater would help to keep the group together more closely and in the end improves safety. I’ve asked the guide to tell me about the planned route under water, which he did in the following dives. That allowed me to take some responsibility myself (I really like to know under water that everybody who went into the water comes out of it as well). That said, there’s always room for improvement, and it didn’t lead to any dangerous situations. Taking responsibility for your buddies is part of diving, and as long as everybody takes it seriously, no problem.
Bahía de Cochinos (Bay of Pigs)
The Bay of Pigs is historically known for an attempt by the CIA to invade Cuba with US-friendly troops and overthrow the then-young communist government. Lack of political support from the US government, underestimation of the Cuban revolutionary troops and insufficient secrecy lead to an utter failure of the invasion attempt. Nowadays, the bay of pigs is a rather calm area, with excellent scuba diving. Basically, the eastern shore of the bay is lined with a coral reef wall very close to the shore. Commonly, one would do a shore entry here, swim out about 100m and then drop into the wall.
I dove with Ronel’s local dive operation. A tweaked bus would pick us up in the morning, go to the dive center (next to the government run hotel in Playa Giron) to gear up, and then drive up North for 10 – 20 minutes to one of the dive spots along the bay, then do two shore dives from there. We’d return around 1 o’clock in the afternoon, so there’s plenty of time for other activities (which, to be fair there aren’t that many apart from the beach and a “not-quite-neutral” museum about the failed invasion attempt).
The Cenote Dive
Cenotes are sinkholes in the shallow limestone ground near the coast. Small pools filled with fresh surface waters lead to extended cave systems flooded with salt water, so one enters a fresh water pool in the woods, then descends through a haloclyne. This haloclyne is the border between fresh and salt water. The caves were usually filled with salt water seeping in from the sea, but as there are almost no currents, rain water that comes in from above stays on top as fresh water. The haloclyne produces a weird disturbed visual effect when one dives through it, but above and underneath it, visibility is clear. These sink holes are often quite deep, the one we entered was 26m deep at entry point, the deepest points of the cave system went down to 60m. We entered into a tunnel, a vertical crack in the limestone about 1m wide, so wide enough to comfortably swim through. During the dive, we made our way about 350m into the cave to a maximum depth of 32m. As the shape of the cave determines the dive profile, I ended up having to add an extra decompression stop before surfacing.
We went through a lower tunnel into a larger cave, which had some beautiful sunlight shining in through cracks above in blue-green colors. Visibility was excellent, and the sunrays produced an almost magical ray of sunlight in the water of the deeper cave. Through the haloclyne above us, the sunlight was broken by the different densities of air, fresh and salt water until they hit the particles drifting in the water or the walls and bottom and of the cave. This dive was guided by a specialized cave diving guide. Briefings were thorough, and after a first reef dive to check everyone’s buoyancy and general diving skills, we did our second dive of the day in the Cenote. I’ve found this video, which gives an impression how such a dive looks like. If you’re an advanced diver, comfortable with overhead environments and experienced enough, I’d definitely recommend doing a Cenote dive, For me, it’s been an unforgettable experience.
Playa Ancón is the beach village close to Trinidad. It’s a peninsula at about 7km from Trinidad. I’ve found it a bit complicated to book the diving there. Tour operator in Trinidad would tell me that everything’s fully booked, but inquiring at the dive center in Playa Ancon, I was told to just show up before 9am and I should be fine. That’s what I did, and it was indeed no problem to go diving there. We’d enter the boat from the beach and would go out a few hundred meters, just too much to swim there comfortably.
Even with a bit of a choppy sea that day, the diving was excellent. Good guides lead me over an interesting seascape with sandbed-“roads” in between coral fields, and much life in between. Highlights of these dives were a wreck, which lay across two large rocks and created a swimthrough this way, a school of tuna (about 40 fish), and a 1.2m large eagle ray. Water was warm and visibility in the range of 15m (considered quite bad for the location, so expect better when you get there). The dive shop was run professionally, but be prepared for a “laid-back scheduling”, which means depending on the day, two boat dives with a surface interval on shore might run into the early afternoon. (I’m mentioning it here, since every other dive center I dove with in Cuba was exceptionally punctual, contrary to what I had read before.)