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Bookshelf: The View from Lazy Point

The View from Lazy Point: A Natural Year in an Unnatural World – Carl Safina

The Carl Safina we (I) know and love – brilliant, lyrical, and wide ranging – returns with this book after his angry eulogy for the Gulf of Mexico (A Sea in Flames) after the Deepwater Horizon oil spill. This book is a return to the style of his other titles, which you should read as a matter of urgency: Song for the Blue Ocean, Voyage of the Turtle, and Eye of the Albatross. If you had to choose one author to be your guide to everything that’s wrong with, and everything that’s hopeful about our blue planet, Carl Safina would be that writer.

Safina won the 2012 Orion Book Award for The View from Lazy Point, but not everyone loves his sometimes wordy style (channeling great American nature writers such as Henry David Thoreau), so he may be an acquired taste. If you like a bit of literature mixed in with your science, I think you’ll love Safina’s writing. At intervals he allows outrage or anger to break through into his reverie; an encounter with duck hunters near his home, for example, left me with my heart pounding.

Lazy Point is a promontory at the end of Long Island Sound, not that far from New York city. Just looking at the area on the map makes me want to go there – it’s in an area frequented by vast numbers of migratory birds and abundant fish species, with an intriguingly convoluted coastline. Safina owns a cottage at Lazy Point, and The View from Lazy Point is structured around the seasonal changes he is able to observe from this spot. The daily walks he takes on the beach with his dog reveal the changing landscape and its inhabitants as the year passes.

Safina is a fisherman, and mounts an impassioned (and relatively convincing) defence of the activity. He also admits that he struggles with it, which I found slightly reassuring. He has given up shark fishing (at least, he doesn’t keep the sharks he catches any more). I’ve struggled with his fishing narratives before; fortunately in this book he’s more concerned with food than sport.

During the course of the year, Safina also travels – to Palau, Alaska, Svalbard, Belize – seeking first hand the effects of climate change and pollution on the marine environment and the people who depend on it. He sees ice melting and coral reefs bleached and overgrown with algae. I didn’t realise the extent to which coastal communities (mostly on islands) are already having their lands inundated by rising sea levels, crops destroyed and homes flooded. The problems and challenges identified in this book are massive in scope, and probably the most important (self-created) threats humanity has ever had to contend with.

After all, only in the last few decades have we understood anything, really, about how the world actually works. … Consequently most of civilization remains uninformed about the two great realities of our existence: all life is family, and the world is finite. … What I’m saying, basically, is that in very consequential ways, our modes of conduct are so out of sync with reality that they’re essentially irrational.

His call to action is justified. You can read an interview with Safina here, and other reviews of this book at the LA Times and New York Times.

You can get a copy of the book here if you’re in South Africa, otherwise here or here. I think you should read it.

Article: Outside on the sinking of the Bounty

Having turned our attention to the mighty Gulf Stream current yesterday, let’s think about the kinds of phenomena that the warm current can give rise to. As weather systems such as thunderstorms move over warm water, they draw water into the lower atmosphere by causing the seawater to evaporate. This water vapour is pushed up, leaving space for more, and the storm grows in power as long as it stays over the warm sea. The Gulf Stream is a warm current in a cold ocean, and is thus a major generator of hurricanes. NOAA explains it properly.

Outside Magazine published a detailed analysis of the sinking of the Bounty during Hurricane Sandy in late 2012. The Bounty was a replica of HMS Bounty, an eighteenth century three masted sailing ship. She was built in 1960 for a Marlon Brando movie about the mutiny that led to the establishment of the pit of despair that is the settlement on Pitcairn Island. (Why pit of despair? Read this.) After the movie was completed the vessel passed through several owners, all of whom struggled to finance the constant repairs and maintenance required on a wooden ship of that scale. Her story concluded in the glare of the world’s media attention, as the ship struggled to stay upright while sailing into the eye of Hurricane Sandy (for reasons unclear).

As the drama of the Bounty’s final hours unfolded on CNN and the Weather Channel, seamen and landlubbers alike were asking the same question: what was a square-rigged ship doing in the middle of a hurricane—a storm that had been forecast for days?

…

But the full answer to why the Bounty sank was much more complex than a captain’s rash decision. It was a story decades in the making, a veritable opera of near misses and fantastic schemes involving a dogged captain, a fiercely loyal crew, and an owner who was looking to sell.

This is a story of a nautical disaster told with a strong focus on the personalities involved. It’s quite a terrifying read.

Read the full article here.

The incident report was released by the United States’s National Transportation Safety Board in February of this year, and places much of the blame for the sinking on the captain’s decision to sail into the hurricane.

Bookshelf: The Gulf Stream

The Gulf Stream: Tiny Plankton, Giant Bluefin, and the Amazing Story of the Powerful River in the Atlantic – Stan Ulanski

Stan Ulanski is an academic with a special interest in the Gulf Stream, both as an oceanographer and meteorologist, and as a keen angler. I was drawn to this book because it reminded me of a book I took out of the school library when I was twelve, also about the Gulf Stream. I remember devouring that book, and have been trying to find it again for much of my adult life. I haven’t succeeded, and this isn’t it.

The Gulf Stream is a fast flowing, warm current that runs from the Carribbean up the east coast of the United States, past Canada, and across the Atlantic Ocean. It is responsible for about ten percent (popular opinion has always held this number to be higher, but it’s not) of the warming of England’s climate, transporting heat from the tropics up into northern latitudes. At the surface, where its flow is fastest, it can move at up to 9 kilometres per hour and the water in the current may be ten degrees warmer than the water surrounding it. Oceanographer/cartographer Matthew Fontaine Maury called it a “river in the ocean”, as it is so distinct from the water surrounding it:

There is a river in the ocean. In the severest droughts it never fails, and in the mightiest floods it never overflows. Its banks and its bottom are of cold water, while its current is of warm. The Gulf of Mexico is its fountain, and its mouth is in the Arctic Sea. It is the Gulf Stream.

The Physical Geography of the Sea, 1855

Ulanski divides his book into three parts. The first section provides an oceanography lesson, as well as a history of how we came to know what we know about ocean circulation. The second section, which I felt could have been beefed up significantly, has a chapter on the plankton, sargassum weed and other small life in the current, and another dedicated to bluefin tuna. I know from Richard Ellis’s tuna book how incredible these creatures are, and I felt that Ulanski could have made more of them. (He may have felt that since tuna have been so extensively eulogised, he has nothing to add – fair enough.)

The final chapter of the second section grated my goat and I struggled to read it – it’s about fishing, a sport of which Ulanski is a keen proponent, and profoundly smug (he “feels no remorse”). I cannot understand sport fishing (or hunting) of any kind: if you’re going to release the animal after fighting it, exhausting it, and injuring it, what have you achieved? The inflicting of a prolonged, possibly fatal wound on a creature at a significant disadvantage to you in your motorised boat with expensive fishing tackle and crafty lures? How manly. We can appreciate how marvelously put together earth’s creatures are without damaging them with our ego in the process. (I realise that other people feel differently, with equal forcefulness.)

Ulanski concludes with an examination of the history of the exploration and colonisation of the New World, both aided and impeded by the Gulf Stream. It seemed that at times he wanders far from his main subject, but it is instructive to be reminded of what was involved in crossing an ocean before the advent of GPS and the creation of detailed charts. The section on piracy is fabulous and created in me a strong urge to re-watch Pirates of the Caribbean.

While my personal preference would be for a heavier focus on the oceanography and marine biology of the Gulf Stream, Ulanski is quite right to include a comprehensive section exporing humans’ relationship to this massive current. It has shaped the settlement and economies of all the lands adjacent to it.

Here’s an incredible visualisation of ocean currents – you can see the Gulf Stream prominently in the Atlantic. What is it like to be adrift on the Gulf Stream? Find out here.

The Perfect Storm deals with the 1991 nor’easter, a storm (not uncommon in the western United States) generated by the interaction of the warm water of the Gulf Stream with atmospheric phenomena. The Gulf Stream is the “weather-maker” of the western Atlantic, according to the author, and these interactions between the current and the atmosphere will become increasingly important and explosive as the global climate changes (and let me clarify, the change has come about because of human behaviour).

If you’re in South Africa, get the book here, otherwise here or here. For an even more wide-ranging view of the Atlantic ocean (minus the marine biology), check out Simon Winchester’s Atlantic.

Bookshelf: The Cloudspotter’s Guide

The Cloudspotter’s Guide – Gavin Pretor-Pinney

Gavin Pretor-Pinney is the founder of the Cloud Appreciation Society (over 35,000 members), and this book is a natural outflow of his immense, self-professed love for clouds. I’m mentioning this book here not because it mentions scuba diving even once, but because clouds form part of the weather system that is driven by the ocean, and furthermore affects all our activities on and under the sea. And, because paying attention to the rhythms of the weather is important amid the regimented humdrum of everyday activities, and is one of the things that enables me to live a relatively sane life.

The Cloudspotter’s Guide is divided into chapters by type of cloud. Pretor-Pinney explains how to identify the different types, how they form, and how they fit into the greater scheme of things. I find meteorology hard to keep in my head, so it’ll bear another reading, but I learned several (I suspect extremely basic – deep ignorance as my starting point) things about how clouds are formed that have improved my understanding of how the world works. This is a great book to take on holiday, alongside your bird book, or to keep near a window so that you can practise identifying the clouds that roll overhead, and start to understand the type of weather that they presage.

The other book I’ve read by Pretor-Pinney is The Wavewatcher’s Companion, and The Cloudspotter’s Guide is the same kind of deceptively simple, amusing take on a fairly complex phenomenon. By the end of the book you’ll have chuckled several times, admired some remarkable photographs of clouds (contributed by Cloud Appreciation Society members), and contemplated booking a plane ticket to Cairns, Australia in order to check out the Morning Glory cloud in person. You’ll also have learned quite a lot.

Did you know, for example, that the contrails (condensation trails) created by plane traffic contribute more to global warming than the carbon emissions of those same planes? The contrails are an artificial cloud that – by increasing cloud cover – trap heat at the earth’s surface and prevent it radiating out into space. You can read more about this here and here – the circumstances that allowed scientists to come to this conclusion were highly unusual.

You can get a copy here or here, otherwise here if you’re in South Africa. You can also grab the companion volume The Cloud Collector’s Handbook, which is an identification guide combined with a checklist (for serious work in the field), here.

Article: Randall Munroe (xkcd) on draining the world’s oceans… again

Randall Munroe of xkcd (all hail!) tackles another hypothetical question, and applies SCIENCE and some thought experiments to come up with an answer.

Supposing you did Drain the Oceans, and dumped the water on top of the Curiosity rover, how would Mars change as the water accumulated?

Last time he discussed draining the oceans, a plug was pulled at the bottom of the Mariana Trench. tl;dr the Netherlands took over the world. This time the water will be transported to Mars and poured into the Gale Crater. What will that do to the Martian landscape?

Emptying the world's oceans onto Mars — Emptying the world’s oceans onto Mars

Read the full article here.

Series: Underwater Universe

The four episodes of this History Channel series cover waves, tides and currents, predators, and pressure – all powerful features of the ocean that can be sensationalised (some more easily than others) and presented for shock value and as imminent threats to human life. Full advantage is taken of this fact.

This very American offering doesn’t boast the measured, mellifluous tones of Benedict Cumberbatch or Steve Toussaint as narrator, but the line-up of (mostly in-studio) guest narrators is quite impressive. Bruce Parker (The Power of the Sea), Susan Casey (The Devil’s Teeth and The Wave), David Gallo (scientist presenter of the TED Talk I mentioned here), Scott Cassell (student of the Humboldt squid), Richard Ellis (writer of a number of ocean history, art and science books), and Neil Hammerschlag (shark scientist) were familiar to me, as was big wave surfer Ken Bradshaw, from this article. The strange, uncomfortable way in which the studio narrators were filmed, with silent close ups interspersed with talking, was very annoying and must have been incredibly embarrassing to shoot. Or perhaps the cameraman took the footage when the narrators didn’t realise they were being filmed.

Unlike BBC documentaries, which tend to rely purely on incredible photography and fluent narrative to convey information, the History Channel favours a CGI-heavy approach that we encountered in Treasure Quest, Deep Sea Salvage, and also in the National Geographic Shark Men series. For the subject matter of this series – particularly the sections on waves, tides and currents – it was very appropriate and informative. The first episode, devoted to tsunamis, rogue waves and “monster waves”, made good use of CGI to illustrate the concepts as they were explained. The series was produced shortly before the Japanese tsunami of 2011 (there is a hastily tacked on “thoughts and prayers” disclaimer) and features interviews with a survivor of a tsunami in Samoa. I am fascinated by rogue waves – the whole episode could have been devoted to them but they don’t make for good television – we only have indirect evidence of their existence. Also, I could have done with more footage of giant ships battling storms, but that’s what youtube is for…

The least interesting and most irritating episode was the one devoted to the ocean’s top predators, which suggested that orcas are a serious threat to humans. As evidence, the cases of captive killer whales drowning and injuring their trainers at marine theme parks were cited. No mention was made of the psychosis that these whales suffer from as a result of confinement in a small, barren, completely unnatural environment. An incident in which orcas inexplicably rammed and sank a yacht in the Pacific Ocean is also described and re-enacted. Whether the orcas did what they did because they wanted to kill the people on board is highly debatable. There is also a half-hearted attempt to paint whales as potentially vicious killers, recounting incidents when sperm whales rammed whaling boats in the 19th century. More power to the sperm whales, I say.

The other dangerous predators were (predictably) white sharks, Humboldt squid, saltwater crocodiles and Australian box jellyfish. There was a small environmental message at the end of this episode, mentioning that squid will probably end up the top predators in our oceans if current trends – fishing out large predatory fish and global warming in particular – continue.

The third episode, on the immense pressures that objects in the deep ocean are subjected to, was very interesting to Tony and me as divers. A confusing interview with a diver whose brother got DCS on a wreck dive leaves (I suspect) much out. Were they even qualified divers? Why was he surprised that his brother felt unwell and confused as to the cause after he popped to the surface from 30 metres after a 30 minute dive?

The bulk of the third episode, however, recounts a 1981 experiment called Atlantis III in which three volunteers were taken in a saturation system to a simulated depth of 686 metres while breathing Trimix 10 (70% helium, 20% nitrogen and 10% oxygen). It took 31 days for them to decompress. The chief of the experiment, Peter Bennett, was the founder and former CEO of DAN. There’s a more information about the project here – worth a read (download the pdf slowly), and a briefer account here.

The series concludes with an episode on tides and currents, including rip currents. The massive tidal range of Morecambe Bay in the United Kingdom, is discussed at length. At low tide, up to 300 square kilometres of mudflats is exposed, and flooded again when the tide comes in. The guides who escort people out onto the mudflats when the tide is out seem like charming individuals – it is recommended not to wander around at low tide without local guidance. In 2004, the rising tide trapped and drowned 23 Chinese immigrants who were working the cockle beds – with such a large expanse of land to cover, the rising tide comes in at great speed. There is also a harrowing re-enactment of a father and his two sons getting washed out to sea in a rip current in Kauai that should make you think twice about swimming at beaches with warning signs on them.

You can get the DVDs here if you’re in South Africa. Foreigners, go here or here.

Article: Slate on ocean salinity

Phil Plait, the Bad Astronomer, writes briefly about images released in June 2011, taken by the earth-observing satellite Aquarius.

As Plait points out,

Observations like this are crucial for us to understand just how our fiendishly complex planet works. Especially now, when our climate is changing, and those changes are evident even year by year.

See the full article here.

Documentary: Wild Caribbean

In the tradition of the BBC’s Great Barrier Reef and South Pacific documentaries we watched last year and earlier this year, Wild Caribbean transports one to a series of exotic destinations and – with the outstanding production values one expects from the BBC – introduces their micro- and macro- flora and fauna, as well as the physical characteristics of the location.

Narrated in mellifluous tones by Steve Toussaint, with a wonderful musical score, Wild Caribbean transported us out of rainy Cape Town to the warm, shallow (and very deep) seas of the Caribbean, the thousands of perfect palm tree covered islands, the mangrove forests, and the magnificent coral reefs. There are four episodes, and we enjoyed the middle two – Wrecks and Reefs and Hurricane Hell – the most. In the episode about the abundant shipwrecks and reefs in this part of the ocean, we saw footage of the Kirk Pride, lying in nearly 300 metres of water on the Cayman wall.

The area is prone to hurricanes, and these events will only increase in severity and frequency as the planet warms up. The episode devoted to hurricanes is both terrifying (with some amazing footage of storm surges) and comforting – in most cases, the coral reefs, forests and animals are able to recover and thrive after these severe storms have passed.

I was also thrilled to get a glimpse, in the fourth and final episode, of the cenotes of the Yucatan peninsula in Mexico, haunt of cave divers and redolent with history and spiritual significance to the people who lived there. Aerial footage (which is used extensively) of the Great Blue Hole of Belize was also alluring.

Chance of being murdered aside, the Lesser Antilles islands of Aruba, Bonaire and Curacao struck me as very promising diving destinations – particularly Bonaire. It is an extremely arid place with very little runoff due to erosion and rainfall, so the coral reefs surrounding it and Curacao are washed by crystal clear water and bathed in abundant sunlight. For divers, there is also magnificent footage of whale shark aggregations off the island of Utila, and of massing stingrays at “stingray city” at Grand Cayman, where one can stand in waist deep water and feed stingrays by hand. Humpback whales, orca and turtles also pass through these waters, which boast an almost dizzying array of macrofauna in addition to the coral reefs and tropical fish.

This is a wonderful production and we enjoyed it immensely. There is a companion book that looks beautiful, too.

You can buy the DVD here (South Africa) otherwise here.

Article: Randall Munroe (xkcd) on draining the world’s oceans

After water has been drained to a depth of 2 kilometres

Randall Munroe, the man behind the xkcd webcomic I love so much, conducts another thought experiment in his “What If?” series, this one related to the ocean:

How quickly would the ocean’s drain if a circular portal 10 meters in radius leading into space was created at the bottom of Challenger Deep, the deepest spot in the ocean? How would the Earth change as the water is being drained?

Check out the Agulhas shelf extending off South Africa in the map above. After even just a few tens of metres of water had gone down the imaginary drain, all the recreational dive sites we frequent would be on dry land.

Complicating the imaginary drainage process is the fact that the ocean is full of mountains and trenches – and many of the mountains are higher than the ones on land. As the water drains, parts of the world’s oceans would become cut off by these mountains and ridges, and stop draining. The step by step illustrations of the progressive changes in the earth’s landmass are surprisingly disturbing. It’s a kind of reverse global warming scenario, where sea levels fall instead of rise.

Read the full article/thought experiment here. Spoiler: we’re all going to be Dutch…

Bookshelf: The Power of the Sea

The Power of the Sea: Tsunamis, Storm Surges, Rogue Waves, and Our Quest to Predict Disasters – Bruce Parker

The Power of the Sea by Bruce Parker is a highly readable introduction to freakishly large ocean phenomena, most notably tsunamis and rogue waves (which have particularly interested me since reading Susan Casey’s The Wave). Parker is an oceanographer who has worked at NOAA.

I was grateful that the author spent some time explaining tides – the most basic oceanographic feature, universally familiar. How can some places have two high tides every day, some places have one, and some have none at all? What about the differences in tidal range around the world? I think I’ll need it to be explained to me a few more times before I’m comfortable with it, but between him and Rachel Carson we’re off to a good start.

In the early sections of the book there is a good deal of historical background provided as Parker fills in the background of modern oceanography, and I enjoyed the accounts of how understanding of tidal phenomena has assisted generals, rebels and others in achieving their goals (or thwarted them). The success of the D-Day landings at Normandy during World War II were critically dependent on predictions of the tide on five French beaches. Tidal data did not exist for those particular locations, and some intelligent guesswork and interpolation was required to determine which days would be suitable for an invasion.

Parker also discusses the expensive and difficult task of defending our coastlines – particularly urbanised, developed locations – from storm surges such as the one caused by Hurricane Katrina. The Dutch are particularly forward-thinking in this regard.

The latter half of the book is mainly devoted to tsunamis, their causes and effects, and the problem of giving advance warning of their approach. In order to understand how tsunamis and storm surges function, it’s necessary to have a basic grasp of how energy is imparted to the ocean. Most of the time the energy is from the wind, and a combination of factors may give rise to waves of unbelievable dimensions, or just to common and garden wind waves and swell. In the case of a tsunami, it is usually an undersea earthquake that gives rise to the wave. A significant portion of the book is devoted to the timeline of the 2004 Thailand/Banda Aceh Tsunami that killed nearly 300,000 people, and the afterword deals with the Japanese tsunami of March 2011 that has led to one of the largest nuclear disasters of all time at Fukushima.

Predicting tsunamis is difficult; in order to do the best job possible, one would need to be able to predict earthquakes, which is in itself very, very difficult. Not every undersea earthquake causes a tsunami. The next best approach – if we can’t predict earthquakes – is to have high-powered mathematical models that can, based on when a tremor occurs, give an indication of whether the resulting waves will be tsunami waves, or not. For this kind of predictive power a huge network of ocean observation buoys and sensors is required. Tsunami warnings are generated and quickly sent to nations whose coastlines are at risk. The notice period is potentially very short, so countries at risk from tsunamis need to have evacuation procedures and good public awareness for these systems to work properly.

All the phenomena Parker describes (except perhaps for tsunamis) will be exacerbated by climate change, which leads to more regular, fiercer storms, higher winds, and rising sea levels. This makes it all the more important to be able to predict what conditions will give rise to the conditions that are conducive to storm surges, large waves, and phenomena such as El Niño. Worldwide initiatives such as the Global Ocean Observing System (GOOS for short), which encompasses a wide range of observational projects, will make it easier to pick up tsunami waves before they reach land, and to provide real time data on developing weather and wave patterns across the globe.

You can buy The Power of the Sea here (if you’re in South Africa), otherwise here or here. For a kindle copy go here.