The last few days have been really busy, which is why I haven’t written much.   We did our last experiments today and then spent most of the rest of the day packing.   It will take us just over 24 hours to get back to Honolulu so we’ll be steaming back north all day tomorrow.  

The weather has been annoyingly calm right up to the end.   As I got better and better ideas about exactly what I wanted to measure, the number of breaking waves went down and down until it couldn’t go down any more because there were none.   Oh well… at least I have data from the start to keep me going.  

I can hardly believe that we only have 32 hours before we arrive in port.   I haven’t got cabin fever nearly as badly as I thought I might, but then this is a very nice ship with very nice people on it and that helps a lot.   I am looking forward to being able to go for a run though – the novelty of stationary rowing machines and stationary bikes has worn off!

I think what I’ll miss most is the dinnertime conversations.  Since I changed subjects so recently and I don’t have a background in oceanography, there are a lot of topics to do with the ocean in general that I don’t know much about.   The people on this ship know all sorts of amazing things and they’ve shared what they know with me with great enthusiasm, mostly at mealtimes.   Discussions about the tiniest solid particles in the ocean over breakfast, why ships are routinely chopped in half to make them longer over lunch and where the weather in this part of the world comes from over dinner.      It’s been fascinating, and I really feel that I have a much better idea of how the ocean works now.   I’ve also learned a huge amount about how light travels through the ocean, what absorbs it, what scatters it and why anyone cares.     

And the desserts.   I will definitely miss the desserts.   I have no idea how you come up with food that nice after three weeks at sea, but it’s fantastic.  I’m beginning to suspect that they’re hiding a cow and some hydroponics somewhere in the bowels of the ship, because I don’t see quite how all this food could be successfully stored for so long.     

Me preparing the resonator for its final deployment.    My hair has grown so long during the past month!

It is 3pm on a Friday afternoon, here on the ship.   If you are going by any conventional calendar, you might quibble with this – convention states that it’s actually 8am on a Thursday morning, Hawaiian time.   But mentally, it’s 3pm on a Friday and I suspect that it will remain 3pm on a Friday until we get into port in 6 days time.    We are on day 17 of a 23 day cruise and we have worked for every one of those 17 days.    Everyone is still working away, and everyone appears quite happy with how things are going.   But the conversations are loopier, the banter has reached stratospheric heights and the crazy ideas being floated are now literally being floated.   This last one usually involves attaching two or three previously unacquainted instruments to each other and rigging up some fantastical way of making the whole thing float or sink as desired.   Then you chuck the whole thing off the back of the ship (in a safe, winch-controlled sort of way) and see whether the simultaneous measurement by these instruments produces any great insight.          Since there’s such a variety of instruments on this ship, this is actually a very scientifically productive game but it can only happen now that everyone has collected most of the data they were supposed to collect.   The homework has been done and now there is time to play.

My stream of data from FLIP dried up when the transmitters for communication between the ships gave up a few days ago, so I can’t analyse those data as they come in any more.   The two resonators over there are generating 2 gigabytes of data every twenty minutes between the two of them, and processing this was putting a lot of strain on my laptop.   So I have time to add my resonator to some of the instrument agglomerations.  

Two of my colleagues, studying the latest instrument clump, which includes my resonator.   Note the improvised buoy on the top and the weight on the bottom to make it float a different way up.

So far, I feel that things are going reasonably well.   I have demonstrated that these resonators can detect the smallest bubbles, and I’ve put limits on how well they can do that.   Small bubbles only cause a tiny amount of attenuation each, so you need many more of them to be able to see the effect.   But still, if you have enough the resonator will be able to see them.   Now it’s all just a case of finding enough bubbles… it’s really been a bit too calm out here to see huge bubble clouds.   There have been a reasonable number of small ones but I’ve been wishing for high winds and big breaking waves.   To the relief of everyone else on board (who didn’t want to have to live on sandwiches because it was too choppy for the cook to cook) none of these turned up.  

Another shark was nosing around the buoy today.   Here’s a picture of a shark near the buoy on FLIP a few days ago:

Today when were were recovering instruments from the water, we quite frequently found very bright blue thin threads wrapped around them.   These were parts of Portuguese Man  o’War, blobby jelly-like things that float around the upper ocean.   They’re not jellyfish, and they’re called siphonphores.   Each one is actually a floating colony of four different organisms, all working together and dependent on each other for survival.   The bright blue is really distinctive.   Some of the very specialized cells in the tentacles are for catching prey and they’ll also give humans a nasty sting.    We hosed them all off the instruments and used gloves when handling the lines.   One was wrapped around the inside of my resonator – I’m not sure whether it would affect the measurement, but I hope not.    I did worry about siphonophores for a while because they contain a gas bladder and that would behave just like a large bubble.    If one got stuck inside the resonator it could cause a few problems, but I'd never seen one until today.

This is part of one that came up on a line with someone else's instrument.

The small boat that is kept on the deck of the ship for tasks that the big boat is no good for was also sent out today.   The people sampling the surface microlayer need to be close to the water and away from the ship to get uncontaminated water, and another group who have an autonomous underwater vehicle (AUV) send  their vehicle out and bring it back with that boat.   The AUV is a cool thing – you program it to tell it where to go and off it goes.   It can measure light and various other things as it goes, and it’s a great tool because those measurements aren’t being spoiled by shadows from ships or humans nearby.   Theoretically it’s supposed to come up to the surface and call home when it’s finished but apparently recently it hasn’t been calling much.   To find it, the researchers in charge of it have to call it to ask it where it is, and usually it’s sitting at the surface basking and showing no sign of any calling home.      

This was the AUV being released this morning.   You can see it in the lower left of the picture.

Yesterday we carried out a well-worn oceanographic ritual.   Every day we make two “CTD casts”.   CTD stands for Conductivity, Temperature, Depth, and it’s a device that has pressure, temperature and salinity sensors on it.      It’s also got “bottles” on it in a rosette shape, which are open at both ends to start with.      The device is lowered down through the water column and someone on the ship monitors the data that it sends back as it comes in.   You get a profile of temperature, density and salinity with depth so it tells you some really basic things about the structure of the water column you’re sitting on top of.   As it is pulled back up (using a large winch) you can choose depths to close both ends of particular bottles so that you have a water sample from that depth.       Anyway, this happens twice a day and recently we’ve been sending it down to 600 metres.  

Yesterday it was decided to send it down to 2000 metres (the total ocean depth just here is about four and a half kilometers), and so it was time to get out the expanded polystyrene cups.   Someone must have brought them along especially for this, because nothing else on the ship is disposable.     One of my colleagues arrived in the lab with a pile of cups and colourful marker pens, and announced “art class time”.   Everyone obediently covered their cup in cartoons, and the cups were put in a net bag which was attached to the CTD.   Down it all went to 2000 metres and when it came back up, all the cups had shrunk to about a quarter of their original size.   Expanded polystyrene starts life as small plastic beads that contain a chemical which turns into gas when you heat the beads up.   So you put the beads into your mould, heat it up, the chemical turns to gas and it pushes out the sides of the beads so that they puff up like balloons.     They push against the sides of the mould and stick to each other.   When it all cools down, they stay as they are and solidify, all puffed up.   They contain loads of air, which is why they’re really good insulation for drinks.      That air is at atmospheric pressure, which is pushing on all of us all the time and normally, the air pushing out from the inside of the bead balances the atmosphere pushing in on the beads.   But under the ocean, as well as the weight of the atmosphere pushing in, you also have the weight of all that water.   At 2000 metres, the push is as strong as 200 atmospheres, so the air inside the beads loses the battle and is crushed by the weight of the ocean.   The beads shrink and stay that way when they come up to the surface.      The drawings on the cups are still visible in the shrunken version and they’re pretty funny things.    I've seen a few around in people's offices.    It’s a proper oceanographer’s souvenir!  

The amazing thing to think about is that any ocean life that lives at those depths, and especially anything that goes up to the surface and then dives very deep (like sperm whales) is used to this incredible pressure.     The whales have to get used to it changing by a huge amount every time they go up and down, in order not to explode when they get back to the surface.   Any gas spaces that they have inside them would compress just like the cups did.

FLIP has got to be one of the craziest inventions ever.   It’s been around for 40 years now and it’s currently floating about a quarter of a mile away from us.   FLIP (the Floating Instrument Platform) is the other half of this research cruise, and there are about 8 scientists over there who are part of the same project.   

FLIP was conceived to solve a problem.   When you want to measure something in the open ocean, if you use something that floats on top of the water, you will bob up and down as waves go past.   I saw a very funny example of this the other day when I put my underwater video camera on the frame with my resonator.   About 20 metres down, the camera passed some fish.   The fish in the video are zooming up and down the screen from top to bottom, but not because they have evolved a fantastic new way of swimming vertically.      Instead, the line which attaches the resonator to the ship is moving with the ship and the ship is pitching up and down in the waves on top.   So if you are trying to measure anything and your aim is to be in the water and let the world go by past your field of view, you have a very tough time doing it from a boat.   Or indeed anything else that floats on top.      Out here, the ocean is over a kilometre deep, so there is no opportunity to attach anything to the bottom.   That’s the problem.    How do you do it?  

You can get around the problem of wave motion if your float is very large, so that most of the forces on it come from deep down in the water column (which isn’t moving very much) instead of the complicated bit with the wind and waves on top.    And so was conceived FLIP.   It is a long ship without engines so that it has to be towed to wherever you’re going.     Once it gets there, they flood one end of the boat and the whole thing “flips” so that its upright in the water.   I kid you not.   The living space is all at the top end, and it rotates on gimbals as FLIP flips.   Then everyone carries on living in there, at 90 degrees to where they were before.    Then, you have a platform which doesn’t go up and down with the waves and so it’s a great place to make measurements of waves from.   And that’s why it’s with us.   It’s floating along at its own speed and we are scooting along to catch up every now and again.   The idea is that the experiments on both ships are testing the same bit of the ocean.  

The disadvantage of FLIP is that space is very limited (because of the rotation thing) so although we on the KM are all very glad that it’s with us, we’re also very glad that we’re not on it.   We have comparative luxury over here, while they… well.   Let’s just say that after the last cruise someone was heard to say that it had been noticeable that different people “ripen” at different rates.   Yuk, is all I have to say to that.      A quarter of a mile is probably about the right distance.   We can see people walking out along the booms, and it’s great to watch.     No-one has any control over where FLIP goes until it flips over again and can be towed, so we're all on a magical mystery tour here, just following FLIP along.

I love the fact that something quite so nutty exists and is still the best way to make some types of measurement, even after 40 years. 

FLIP in Pearl Harbor before this trip (photo courtesy of Marlon Lewis) and FLIP this morning, just a hop, skip and a jump away from us.

Things were going surprisingly well until two days ago.   I should have known that it wouldn’t last.   Experimental science isn’t like that, especially when it involves an instrument which is one of the first of its kind.  

My bubble-detecting acoustical resonator had a bit of an electrical upset one morning and several things needed to be reset.   When it was working again, the spectrum that it produced looked different, in a way that generated a nasty sinking feeling.   I have looked at data from four resonators.   The first three all had two features which were odd, but I couldn’t explain them and so I did my best with interpreting the data in spite of that.   But I never really trusted what I saw.      Then, just before this cruise, a new resonator was made which behaved in a completely different way.   It did all the things that resonators are supposed to do, but without the weirdness of the others.   This made me very happy and this new resonator and I collected great data for six days, until an Electrical Hiccup occurred.    And now its spectrum looks just like those from the other three resonators.   Hmph.      So I took it off its frame and took it to a large bucket in the lab to do more tests, which never actually got started because of Electrical Hiccup Number Two.     This one stopped the receiver electronics doing their job so that I can’t hear what the resonator is up to any more.  

I’ve tested what I can, and I’m currently waiting for advice on whether there’s anything I should know about what’s inside the box of electronics before I start taking it apart to see whether we can fix it.   As we all know, the task of taking things apart is of considerably less importance than the task of putting things back together again, so I’m a bit apprehensive about this because I didn’t build the electronics.    But I have to do what I can to get it working – as someone else here said, “it’s broken already and that makes it fair game – you can’t make it any worse”.  

Update:   It turns out that the culprit isn’t inside the big box of electronics after all.   It’s a pre-amp which is permanently wired into the cable that connects the resonator output to the box of electronics.   This is bad because we can’t fix it – in order to make this pre-amp waterproof it was completely encased in epoxy so I can’t get inside to change anything.   The good bit is that apparently there is a spare on FLIP, which is just about a mile away.  More bad news is that the waves have been pretty big recently and it isn’t safe for small boats to make the crossing until it calms down.    So maybe I’ll get on with more data analysis for the time being.   I’m sorry that I’m not getting to dunk my resonator in the ocean for the next few days, but at least the problem might go away soon.

The diagnosis and then the thing on the lower left is the culprit, looking fairly impregnable.

There’s a rhythm to life on the ship.  As the science party on board, we’re less exposed to it than the crew (they work shifts), but we still feel it.     It starts even before the sun pops out and it begins to heat up outside.   Most of the scientists are up and about before sunrise, getting started on the day before breakfast.   Meals are at fixed times, and people usually come in at the start of the allocated hour.     We have a fairly rigid schedule to stick to during the day and most of us are aware of what is going on out on the back deck at any given time (possibly because we’re sitting in the shade and watching).     Usually, each day’s schedule is very similar to that of the day before, because people are making the same measurements each day and watching  how things change day by day.     We have an evening science meeting every evening just after sunset, and then everyone disperses again to work or read or play cribbage, the latest ship fad.

There are different concerns and events each day but after seven days I think that we’re all tucked cosily inside the rhythm of a self-contained shared living space, happily roaming the seas in search of knowledge.   Or possibly just roaming the seas while waiting for dinner time (it is rumoured that there will be be blueberry pie for dessert).  

Favourite scientific remark of the day, heard at the dinner table while discussing how bacteria affect light in the ocean and in answer to the question   "do different bacteria have different refractive indices?"    The answer:  " Yes.   If you starve them, that changes their refractive index.   ".        How on earth did anyone find that out?

Sunset over the Pacific, and someone who is appreciating the relaxing rhythm of the back deck.

We’ve settled into a routine now, and mostly things are running pretty smoothly.    The picture on the right below is a typical scene during the day on the back deck.     You can see the side of the green frame that is used to lower instruments into the water, and the black object in the middle is about to be lowered down.    Elly (one of the ship's techs) is on the right, and the experiment is being run by Scott and Hemantha.

  We moved back south again (we’re now at 18 N, 155.5 W) and we expected to find reasonably high waves when we arrived, but it’s actually been quite calm.   Hopefully that won’t last - I still want lots of bubbles to count!      Today I attached my underwater camera to the instrument when it was sent down into the ocean, and it recorded video continuously for half an hour.   It was pretty interesting (if you like waves and light and the bottoms of ships), but I think that it’ll be more interesting if it’s pointed sideways next time instead of straight up.   I could see bubble plumes forming at the back of the ship, and below is a pretty clear image of one of the rear screws.    Isn’t the ocean colour amazing?   The real reason that I wanted to attach the camera was to see when a cloud of bubbles goes through the resonator, and to get some idea of where in the cloud the resonator is.    

I was disappointed that we didn’t see any fish on the video.   Someone caught a fish off the back of the vessel today, and there must be lots out there.   Not this one though - I think it’s destined for tomorrow night’s dinner table.   

My experiment is an acoustical resonator, which is a bit like an echo chamber.   It is made of two flat plates facing each other.  One of them generates sound at lots of frequencies (a mixture of high and low notes), and then the other plate detects the sound after it has bounced between the plates many times.       When bubbles wash through, they take energy out of some of those frequencies.   Large bubbles take energy out of the low notes and smaller bubbles take energy out of the high notes.   If you compare the sound when there are bubbles and when there are no bubbles,  you see that some notes are quieter than others, which tells you that there are certain sizes of bubble between the plates.     Theoretically, this means that you can count how many bubbles there are of each size.      My main task for the past few days is to see how sensitive it is – how many bubbles of each size have to be there before I can detect them.   I think that I’ve worked that out now, so from tomorrow onwards I can focus on the measurements themselves, now that I know where their limits are.  

The storm that was nearly a hurricane has turned south  and is fizzling out rather wimpily, so we didn’t need to run and hide behind the islands after all.   However, we still decided to move to the sheltered side of the Big Island of Hawaii, so that we could sample in calmer waters.   Unfortunately for me it’s so calm that there are very few breaking waves and consequently very few bubbles, but everyone else is excited by a sort of greenish slick covering large patches of water round here.   What we can see is a cyanobacteria called Trichodesmium.   A single cyanobacterium is too small to see, but these ones clump together into long strands and you can see the strands quite clearly.   Darwin and Captain Cook both wrote about these when they were sailing through this ocean, and Cook wrote that the sailors called it “sea sawdust”.     It’s a cool organism.   It can make its own nitrogen compounds which is relatively unusual, even though every organism needs to get these from somewhere.   Mostly they’re just recycled around the food chain, but the cyanobacteria that we can see aren’t dependent on having any other food source around – they just make their own out of the chemicals in the water and the air.     They also make a sticky substance that clings to their surface and protects them from the fierce sun  by absorbing UV radiation.   So they make their own fertilizer and sunscreen!     They also stick to everything that touches them and they don’t smell very nice, but I suppose you can’t have everything.

I spend some of my day today modifying a buoy with an instrument on it.   The instrument sends pulses of sound down into the ocean below it in four different directions.   By analyzing the sound that bounces back, it can calculate the currents in the top 24 metres of the ocean.   Ours is attached to a buoy so it floats, but we need to tether it to the ship so that we don’t lose it.    And the problem with the tether yesterday is that it was pulling the buoy over sideways so that it couldn’t send the sound downwards properly.     The solution seemed to involve splicing rope, which I’d never done before.   Before I knew it, I had a “how-to” book, a knife and a thing called a “fid” and two other metal loops called thimbles.     So I sat down and had a go, and my splice hasn’t fallen apart yet although it is a bit lumpy.      It did take the weight of the buoy, so I suppose that counts as success.  I  do like the fact that a 17^th century technology is still needed in order to deploy a piece of 21^st century technology.   

Me and my splice.

Testing my bubble-detecting resonator in the lab on the ship.

Today was our first full day of sampling.    The weather is still mostly clear and sunny and it’s pretty hot outside.   One of the researchers here has a cool little piece of equipment that tells the temperature of objects you point it at, by measuring the infrared radiation that they emit.   Apparently the metal deck reached 50 degrees C this afternoon!   Even if bare feet were allowed in that area, it’s something that only the brave and determined (and possibly stupid) would try.   

There is one winch on the back deck that we’re using to put our experiments in the water, so we have a schedule to share out the time.   The rest of each day will be spent analyzing data and fixing any problems that occur.     My first instrument deployment was this afternoon, and it looks as though it went pretty well.   The water is so clear here that you can see the bubble clouds really clearly for ages after they form.     The bubbles stay down for a surprisingly long time – I’ve watched clouds that have easily lasted more than a minute without really spreading out or reaching the surface where the bubbles would pop.     Unfortunately, most of the bubbles that I detected this afternoon are generated by the ship as it moves relative to the waves coming past, but it’s great to be able to see the bubble clouds.     By tomorrow the data from today should be analysed and hopefully I’ll be able to see the sizes of the bubbles in those clouds.  

The light patch in the photo is the bubble cloud underneath the water, just after a wave has broken over the top.

I’m pretty sleepy now and I’m looking forward to being rocked to sleep by the ship tonight.    It’s something I could definitely get used to!

We've been underway for almost 24 hours now and we're steaming out towards our chosen start point at 18 N, 155.5 W .   I spent most of the day unpacking the experiments I'll be using and checking that everything works.   So far, so good, but none of it has been in the ocean yet.   The ocean is a very bright blue colour and it's so clear.   I didn't know that water could be this colour out in the really deep ocean where we are.   This ship (the Kilo Moana, mostly called "the KM" for short) has double hulls, so you can stand on one at the front and look down on the other.    And you can see everything under the water!  

We have two whole days at our starting station before the other ship (FLIP) joins us and the experiments start properly.   Today we're going to move around a cross shape a few miles long and measure how well light is transmitted through the water everywhere on that shape.  The idea is that we will find out whether these optical properties change over short distances in the ocean, or whether we can measure at one spot and assume that this one spot is typical of a larger area.     I'll be working out how to attach my resonator to the other experiment that it will sit on when it goes down into the water, and checking that all the electronics are working properly.  

And there were dolphins playing in the wake of the ship yesterday, so that means we must have had a good start to the cruise.

It was so much fun to see everyone again for the pre-cruise meeting.   We have a great combination of experimental experts, who measure waves, currents, where the light goes in the ocean and lots of other things, and there are also theorists who see whether they understand the physics behind what the experimentalists observe.     We spent two days discussing results from the past cruise and organising the details for this upcoming cruise.    Then I spent a day in a university lab here, doing some extra tests on the resonator.   These are really helpful because you can control almost everything in a lab, so you can see the influence of isolated actions without having to worry about everything else changing as well.   I learnt a lot from those tests, but I'll still have some work to do on the ship before I can interpret the data as it comes in.  

Today it was time to load the ship.   We took all the boxes with the equipment (four huge boxes for an experiment that's actually very simple!) and they were hoisted up on to the deck of the ship by a crane.   Then we made a quick trip to Home Depot (that's like B&Q) for last minute bits and pieces - rope, tape, a bucket, cleaning supplies and some spare nuts and bolts.    Shopping for science really isn't any different to any other sort of shopping.    It all has to come from somewhere and no-one else is going to get it if you don't.  

Tonight is my last night on shore.   We'll all sleep on the ship tomorrow night in port and then the ship will leave early the next morning.   I've got about 18 hours more to remember anything I've forgotten so far and then I'm stuck with what I've got for the next 24 days.   To be honest, that makes me quite nervous... we'll see whether I wake up in the middle of the night tonight with extra ideas for things to do before we leave.   Here's hoping not...

Well, Hawaii actually.   But still in the Pacific ocean.    The last few weeks have been one long roller-coaster ride, but now I've got two days to go until the start of my trip and most of the problems have been solved, most of the logistics sorted out and mostly I'm still sane.     These things are always hard to prepare for because you have an absolute deadline - you have to turn up to meet the ship on a certain date - and there is no wiggle-room if things aren't working.   If your experiment doesn't work when you're at sea, tough luck.     The acoustical resonator that I work on has collected data in the past and I've been studying the best way to interpret that data to get at the bubble population in the ocean.   The idea is that we can test for smaller bubbles this time, but it's not been clear whether the instrument can do that.     I think that I've mostly solved the problem, but I need to be with the resonator to test it out.   The resonator is currently being shipping to Hawaii, but I've been offered a bit of lab space for a couple of days when I get there, so I can do some tests before we're on the ship.  If the data can be interpreted, it'll be very exciting because no-one has really made this sort of measurement before.  

So when we arrive in Hawaii, we first have a meeting with all the scientists who will be on the ship.   It's a great mixture of people from different universities who study different aspects of the ocean, so I always learn a lot when we meet.    Then I have two days to play with the resonator in the lab and then we go to sea for 24 days.   Hopefully during that time we'll get some good variation in wind and wave conditions, so we can see how those conditions correspond to different things we see in the water.  

I'm getting properly excited about it all now, but I'll feel much less nervous after I've done my lab tests next week.   And for anyone who is jealous about working in a "tropical paradise", have a look at the weather forecast there for the next week.   A hurricane arrived there yesterday and rain is forecast for the rest of the week!

I've just moved on to the next part of my project and even though it's still very theoretical it's much more fun.   It involves making numerical models of my experiment, so I have to write the physics of the process into a computer program and then let the program run to see if what the model produces is the same as what the experiment produces.    If I include all the right physics, I should get the same answer.     It's fun because it's really testing my understanding of what it is I'm doing and I'm much more confident now that I understand all the details of what's going on.   The experiment is basically two circular plates which are parallel to each other with a gap for water in between.   Sound bounces backwards and forwards across the water between the plates and from the way it behaves, we can tell whether there are any bubbles in the gap.   At least that's the theory.   So my model follows this process, calculating the expected sound with each bounce.  

To do this in enough detail takes a while though.   I've never had to run huge numerical experiments (that's what this process is called), and this one sets a new record for me.   It took 35 hours this weekend to do all the calculations!   At least I just had to set it going and wait until Monday to see what it had produced.    Now I have to look at the results in detail to see what I can learn from them.   I've also got  a trip to Canada coming up, so that I can do some work with the real experiment itself and make some practice measurements in the bay next to the university.   After that, it'll be next stop Hawaii to carry out the full experiment!  

As I delve deeper into the context of the physics I'm doing at the moment, all I seem to find is more and more information about the really serious state that the oceans are in.   I'm not sure whether this is just because I automatically hear much more about it now that I work in this field, or because it's finally getting the much-needed press and so this stuff is being found out in the public sphere more and more.  

In one way, I'm lucky because at least the science I do is contributing to knowledge of the way the earth's systems work, and in that sense I feel that I'm at least doing something positive about this issue on a daily basis.   Bubbles are at a crucial place on the boundary of the ocean and atmosphere and better knowledge of how many there are and where they are can only improve our understanding of the exchanges between these two great reservoirs of air and water.    On the other hand, all this will have a benefit a long way in the future (it'll probably be ten years before models that incorporate this sort of data are really being used regularly), it seems that there is less I can do on a daily basis.   I choose stuff in the shops that has travelled as short a distance as possible to get there, I limit travel by car as much as possible, I don't buy stuff I don't need (like silly plastic toys that are only going to get thrown away), and I try to be aware of the consequences of my choices in life as much as possible.   I truely believe that all of those are important things to do.   And many people could do more of them and I could do better - it's all dependent on the availability of information and the availability of real options.   

However, I also feel that as a scientist, there should be more I can do.   After all, I understand the issues better than most people, because it's part of my job to do so.   I understand how science works and how the evidence leads to these conclusions.   I have spent time in the oceans, and I've seen some of the effects of environmental changes (and I can imagine more).   Maybe I need to have more patience, and I'll see places to do something extra soon.   But I feel that one of the biggest motivations for really changing your life to at least stop the problems getting worse, if not to start to reverse the recent trends, is knowledge and understanding of what is happening.   Really understanding it, not just looking at a picture of an ice floe and thinking "well, that won't be there in the Arctic in the summer in ten years time".    People really need to understand what it is that has been done, and then very quickly get over most of the anger and sadness that this knowledge causes and move on to actual changes that can be made.   Many of them are personal and they start with better informed consumers and voters.  

Some days, when science is a hard thing to do, when there are tough deadlines and a lot of responsibility for creating my own projects and direction, and when I'm floundering in new understanding of something, I wonder why I do what I do.     And then I realise that I'm one of the few people that really has a unique role here, to communicate what is happening from direct scientific knowledge and to convince people that these changes to their outlook and lifestyles really are important, and that they do make a difference.   There needs to be a connection between the scientific facts and the individuals whose actions have caused those facts.   And that divide should be bridged by a scientist.

If you're interested, a great place to start informing yourself about ocean-related issues is the Shifting Baselines project and also the blog below:

http://www.shiftingbaselines.org/index.php

http://scienceblogs.com/shiftingbaselines/

And number one thing (in my opinion) on the list of "things that you could change but you probably don't really know about" is to think very hard about any fish you may eat.   Overfishing is causing tremendous damage to the ocean, not just because of the removal of fish but because of the massive habitat destruction that dredging causes.   There are some fish that are still sustainably harvested, and try to find that out.   In the UK, I'm not sure about the best sources, but the Monterrey Bay Aquarium has  a great website with recommended alternatives to some of the fish that are found in the US:

http://www.mbayaq.org/cr/cr_seafoodwatch/sfw_sushi.aspx

Underwater Scientist:

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Scuba Science:

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I've been quiet recently because I've been working hard.   I got back from a research cruise and plunged straight into my new job in Rhode Island properly.   And after four weeks of reading and looking at the data, I think that I finally understand enough to start to interpret the data correctly.   It's taken a while, but it's worth it because now I can really contribute properly to solving the problem.

The problem itself is an interesting way of finding bubbles that are too small to see, lots of them.   The experiment works by surrounding those bubbles with a sort of echo chamber.   Imagine standing between two really high flat cliffs, and shouting at one and then hearing it bounce back off the first cliff so you hear the first echo.   But the sound keeps on going past you and bounces off the second cliff behind you so that now you hear a second echo, and this keeps going past you again back to the first cliff, so that you are stuck in the middle of all the bouncing sound between the cliffs.   Well, the experiment puts flat plates on either side of some bubbly water and sends sound from one plate to the other and lets it keep bouncing between the plates.   And the bubbles are in the middle.   However, some bubbles get in the way of the sound more than others. and for example small bubbles get in the way of the high notes more and larger bubbles get in the way of the low notes more.   So, if you send some sound out and get it bouncing regularly between the plates, you can measure how much the passage of each pitch of the sound is weakened as it bounces around.   And from that you can work backwards and see how many bubbles of each size there must have been.   Clever, eh?  

Well, it'll be clever when I've got it to work, anyway.   At the moment, I've just got lots of files of recorded sound and the next step is to work out what they mean.   I'm really looking forward to it now that I understand how to go about it though!

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I have spent the past two weeks doing a scientific scuba diving course at Scripps.   If I want to be able to set up experiments underwater to watch what the ocean is up to from the inside, I need scuba to help me do it.   I already had some PADI scuba qualifications, but the scientific diving certification is a separate, professional qualification.   Soon after I first arrived at Scripps and joined the world of the ocean scientists, it became apparent to me that my experience of what it is actually like underneath the surface of the ocean was almost non-existent and that this experience holds the key to really understanding what is going on down there.    So now I've made the first steps to being able to work underwater.

The course was a lot of fun.   Most of it was practical - extending skills that all divers should already have and introducing some new ones, like how to move heavy objects about on the bottom (with a thing called a lift-bag, in case you were wondering).   The theory is pretty important too though - you really live the effects of physics down there.   You have to understand the effects that the water pressure at depth has on your breathing and your equipment.   What you notice more though is what the pressure does to your ability to be neutrally buoyant (that is, to be able to stay stationary in the water column, without going up or down).    Fish do this all the time without any problem, but then they have evolved to be down there and humans certainly have not.    It's an amazing place to be though.   Hopefully I'll be able to put some experiments down there soon to see exactly how amazing...

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The orange fish in the 2nd picture is a Garibaldi - we practised doing surveys of these in the kelp beds off La Jolla.

I've just finished my first couple of weeks on the east coast.   It's been fun, but it's very different.   Everyone in my building at Scripps did the sort of small-scale physics that I did - bubbles and acoustics and things that weren't bigger than about 10 metres in size.   Now I feel I've found the real world of oceanography, and everyone here deals with HUGE things - phenomena that fill whole oceans, thousands of kilometres wide and kilometres deep.   Just to give you an idea of what that's like, imagine looking out of the window of an aircraft when it's at cruising altitude.   Most commercial aircraft fly at around 39,000 feet, so about 12,000 metres.   The deepest part of the ocean is 10,924 meters (35,840 feet) below sea level, in the Mariana trench.    The average depth of the ocean is 4,000m.   So imagine looking down from a plane, and imagine all that depth filled with water.    That's how deep the ocean can get.   And try to image half or a third of that depth.   That's the depth of most of the middle bits of the world's oceans.   And it's not all the same sort of water all the way down - the temperatures changes, and the amount of salt changes, and the nutrients dissolved in it change.   And funnily enough, it doesn't tend to mix up.   It's all stratified in layers, so the top one kilometre of water might all be sliding along to the north and then 3 km further down, a saltier colder stream of water, hundreds of kilometres wide, is sliding to the south.    And so there's a giant conveyer belt with all these bits of water slowly moving along, not really mixing much, just moving around the earth.   Some "packets" of water will take thousands of years from when they become cold and salty and get pushed down until (after travelling huge distances around the earth) they finally surface again.   It's incredible!

I'm not sure that bubbles are relevant to all those huge processes, but it's all part of the same context.   So I've spent much of the week learnng about what other people do here and trying to get my mind round the distances and times involved.    Bubbles suddenly seem to be very very tiny things.... and yet they are important on a planetary scale.    Amazing.

I finished at the Scripps Institution of Oceanography on Friday... it doesn't seem as though it's been a whole year since I arrived!  I've learnt so much in that time... so many things about the ocean and the system of atmosphere, land, ocean and ice together.   At least now I feel that I can see my own way forward in this field, which I couldn't do a year ago.   Next on the agenda is a short spell working at a different university here, with someone who is writing a book with my boss from Scripps.   It's a nice step because everything I did in San Diego was on one or two bubbles at once, and now I understand the basic theory and the experimental difficulties for that situation.   The bloke I'll be working for next is doing research into millions of bubbles going ping at the same time... which sounds rather intimidating.   Hmmm.   But at least now I know the basics, so I have something to build on.     So I'm off to the University of Rhode Island in three weeks, after a trip back to the UK to see my family and friends.   I'm sure that San Diego has spoiled me and that I'm going to be really shocked when it rains for three weeks straight, but I'll get used to it again.   At least I hope I will...

Suddenly it's all really busy.  I have two more weeks at Scripps before it's time to go across to the east coast of the US to visit the university I'll be working at in June, and then to come back to the UK for two weeks.     It's going to be a really exciting summer and I'll get to chance to work on bubble projects that are looking at the physics of millions of bubbles at once, instead of the one or two bubbles at a time that I've been doing up until now.   I'm still excited about diving in Curacao as well!    But in the mean time, there are two weeks to go and I've got to finish up my current project.   The modelling has been going well, but there's one more aspect to address before I have all the evidence for a complete story to tell.    It's to do with how smaller bubbles experience a smaller snap than larger bubbles, just after they pinch off.   We don't really know the details of how much the snap (imagine an elastic band being stretched and then snapping back) changes as the bubble gets smaller.   So in the next week, I have to come up with a way to make a reasonable estimate, and then the results from the models will be the results that are published.    It's a nice problem, but it's a bit harder to concentrate on it when there's so much other preparation to do.  

The adrenaline is rushing and the clock is ticking...  this is fun!

We got back from Woods Hole on Wednesday and I really got stuck into making a model for the little jets that form on the inside of my bubbles.   I've been looking carefully at the measurements I got from the photos and I'm trying to understand which bits of physics are most important as the bubble splits.   If I come up with a working model for this simple sort of bubble, it means that when I'm looking at the more complicated fragmentation events that happen in the real world, I'll already know which things are probably most important.   Then I can focus my time on looking at them.   It's really interesting to look at all the clues and see if I can work out the most important bits - if it's happening, it must be happening for a reason.

But this week has been disrupted as well... you may have heard about the huge wildfires which have burning around San Diego this week and the university has been closed for a week as a result.   I've not been directly affected but members of my lab have and it may take some time for things to return to normal.    Hopefully there'll be more research to report next week...

I'm now at Woods Hole Oceanographic Institution on the east coast of the US and I had thought that  in this entry I would be writing about how the ocean experiment is going.   But unfortunately, it's not going at all.   There was some mix-up with legal things and permits earlier in the week (not the fault of the academics, just insidious bureaucracy), and the experiment has been cancelled for the time being.   It's all to do with permits to conduct acoustical experiments in the ocean - there are strict controls on using sound sources under the ocean because strong sounds can affect local wildlife.    The reason for using a sound source to do science is that if you send a known signal out from one place and then record how it's changed when it reaches another place, you can find something out about what was going on in between those two places.   In our case, I think that the sound sources were pretty quiet, but the rules for permits still apply.  

It's a shame, but we're all still here at the deployment site on Cape Cod for another couple of days.  It's actually really nice to have the chance to work somewhere nice and quiet without any distractions for a few days.   Sometimes it's hard to really concentrate on reading and writing because there are so many other little tasks that need sorting out, so being somewhere else entirely for a while is great for getting things done.    I'm hoping to finish the paper that I'm writing on the first set of bubble experiments by the end of the week.   It's also time to start thinking about which experiments to do next and that's quite exciting, because there are so many interesting things to do and new directions to take.   It's amazing how many things there are to know about bubbles and how many of them haven't been explored properly yet!

It's all been pretty busy recently.   I've been finishing a journal paper on the first lot of bubble experiments that I did, which mostly involves thinking hard about exactly what I want to communicate and which bits are the most important.   It's when the science really gets done because you have to try to look at what you've written with the eyes of someone who has never seen it before and try to imagine what questions you would ask if you were reading it for the first time.   Then you have to make sure that those points have been covered.   It's nearly done now though, I think...

And then I've been getting ready to go to Woods Hole Oceanographic Institution near Boston with the rest of my group.    While I've been doing my lab bubble experiments, they've been building a series of experiments to look underneath breaking waves.   These are all attached to a single large frame which will be dunked out in the ocean to make measurements in real waves.    The experiments will all be attached to computers on a ship with a large cable so that they can be controlled from the surface.   Divers are needed to put them down on the ocean floor and although I won't be diving, I'll be helping out with the surface technical and experimental stuff.   It's pretty important to understand both ends of the spectrum of wave experiments and to be able to link the complicated nteracting effects that you see in a real wave with the physics that you see in a more controlled environment in the lab.   Hopefully I'll get to learn lots about how to build proper ocean experiments, so I'll get a good view of ways of learning about the ocean.   You can't control real events in the ocean in the same way that you can control an experiment in a lab, but that's the natural situation that you ultimately want to know about.   It all sounds pretty exciting...

I bought a big poster of a breaking wave this week, to go in my room at home.   Just so that I don't forget why I'm here...

I've been preparing the diagrams for the paper that describes the research that my boss and I have just finished work on.   He did some computer simulations of the experiments that I've doing, and the results of his calculations fit my experimental data very well.   This means that it's pretty likely that the bits of physics he used in his model were the most important ones in real life, so we have demonstrated that we probably understand where the energy for bubbles to make noise comes from.   When bubbles break up into smaller bubbles, the new small bubbles go "ping" and send out sound into the ocean.   That sound represents energy and so we have explained where that energy comes from.   Energy is not created or destroyed, so to understand something that happens, you have to know where that energy came from.     The next stage is to publish our paper in a scientific journal, so that other scientists can read it and comment on it and use that piece of knowledge to develop other areas of knowledge.      It will take a while until it appears in print though - sending our paper to a journal is only the first stage.   They will find other experts in the field to anonomously read it and comment on it and to judge whether the evidence supports the conclusions.   We might have to make a few changes to improve it - this is often a way of improving scientific papers, because when you have spent months working on a problem, you might take some things so much for granted that you forget to explain them clearly enough in the paper.   Also, you might have to defend a particular conclusion with some more evidence.   When all of that is done (it sometimes takes six months or so), the paper will be officially published.  

It's quite exciting to really think about the conclusions of a set of experiments - you can see the whole picture of what you were doing much more clearly and do a lot of thinking about the implications and how it fits in with research that other people have done.  

And next week, I'll start a new set of experiments to explore one of the details of the theory.    So many questions to answer!   And the answers are just sitting in the lab, things that happen every day in my experiment that I haven't looked at yet.... we'll get to the deeper secrets of the bubbles yet....

I've finally finished the pictures that I need for my first project here at Scripps and so this week I'm collecting together all the data I have and making sure that there are no little bits I've forgotten to do.   It suddenly seems as though I've done a lot, and it's nice to be tying up the loose ends.   I have the second part of this project to think about now, to look at bubbles breaking up into smaller bubbles in flowing water, rather than being formed at a nozzle.  

The other main task is to find a new direction to go in, so I've been reading more and more about bubbles in the ocean.   My boss told me yesterday that bubbles can be important in helping clouds form, for a really bizarre reason.   To make a cloud,  water in the air needs something to condense on to, in order to start it off.   Once you have a little water drop, it's easy for more water to fall on to the surface and make it bigger but it won't condense on to nothing at all.   So to make clouds, you need some very small particles around to get the cloud going.    And there's where the bubbles come in useful.   When a bubble comes to the surface of the ocean it's probably got lots of little organisms called plankton stuck to the outside of it, if it's been floating around for a while.   When it gets to the surface (imagine a bubble rising to the top of a glass of coke) it joins the air so quickly that it sends up a little squirt of water - you can feel those squirts if you put your hand over fizzing coke.   But all the plankton can't get away from the bubble quickly enough so they get caught up and mashed in the jet and then squirted out into the air.   The water evaporates pretty quickly and then we are left with bits of the insides of plankton floating around in the air - just what is needed to encourage clouds to start to form.  So you get clouds.    Weird, eh?

I feel that it's been an easy week - it was July 4th on Wednesday so no-one was at work, and it's been pretty quiet for the rest of the week too.   I have two current aims.   One is to take really pretty pictures of the bubble phenomena that I've been studying, so that the published pictures are really polished.   The other is to keep reading around and learning more about bubbles so that I can take my own direction soon.   At the moment the project I'm working on was someone else's idea and that's fine to start with, but I'd prefer to be working on my own stuff.   And that's perfectly possible, it's just that I have to come up with good things to do first.   As I'm so new to bubbles physics, it's a bit harder than normal because I know less about the field in general.   But it's a good excuse to read and learn lots!

And a major benefit of being a physicist in an oceanography department is that I get to learn lots about the oceans in general, without really trying.   This week an e-mail went out to the whole department about the discovery of an "octosquid" (see  http://starbulletin.com/2007/07/05/news/story03.html
) .    It doesn't look like the sort of thing I'd like to bump into on a dark night, but it's pretty cool that it's there at all.

There's a famous comic poem, Albert and the Lion (see http://oldpoetry.com/opoem/7686-Marriott-Edgar-The-Lion-and-Albert for the whole thing), and one of the lines from it is:

"They didn't think much to the ocean - the waves, they were piddlin' and small"

Well, the Ramsbottoms should have come to La Jolla, California.      I went surfing for the first time yesterday and that line kept running through my head.   Surfing is a huge amount of  fun, but it was also interesting to actually be in the sort of breaking waves that relate to my bubbles in the lab.   On Thursday my boss and I had a long discussion about how big the biggest bubbles in a breaking wave are.   And he finished it with "Well, go out and look and you'll see them".    And I did - bubbles a few centimetres in diameter which are there for very much less than a second before they break into smaller bubbles.    When you're learning to surf, you spend a lot of time scooting around on those big bubbles, and lots of smaller ones as well, and as you get closer to the beach the bubbles get smaller and smaller as they fragment.      I've played in the waves lots of times before, but I've never really looked at them.   And now looking at those fragmenting bubbles it's my job.   Weird, but pretty cool.  

My experiment is constantly being adapted and this week I spend time looking at the jet that squirts up inside each new bubble as one big one breaks into two.   Seeing the jet isn't easy because the sides of the bubble act like a lens and actually hide it.   So I've been messing around with trying to get the lights in exactly the right plact to see it.    The picture here (if it works this week) is sort of cheating because I was making bubbles very fast which makes the jet bigger and easier to see.  

This week in the lab I started building an exploratory high-speed camera system.   They don't have a high-speed camera in the lab (they cost about a quarter of a million pounds each and this is an acoustics lab so they don't have things like that lying around), so it's back to the old-fashioned technique of strobe photography.   This was used to take some of the classic high-speed images around 1900 and it works because even if the shutter of your camera is open, if it's dark you will not get a picture.   The trick is to open the camera shutter for a relatively long period of time in the dark and only flash light when you want to see something.   It's a bit like the strobe lights that are used in nightclubs and light shows, but my strobe lights are far faster.  I have two lights and I've wired them up so that they flash only 50 microseconds apart  - you could fit 6000 flashes into the time it takes you to blink an eye.

So I don't miss the interesting bit with my photographic flashes, I need to have a very accurate trigger - something to tell the flashes when to start.   So I also wired up a "light gate" - a laser beam with a sensor on the other side.   I can choose where to have this and when the light path is broken (for example by an escaping bubble), the electronics will start the flashes.      It's a pretty crude system at the moment compared with some of the high-speed camera systems that are professionally manufactured, but it will do just as well for what I want it for.   And it didn't cost a quarter of a million pounds.   Hopefully next week I'll use it to take some pictures and I'll post them here if I do.    

I really enjoy building experiments like this, trying to do things that are a bit beyond the easy stuff and using a lot of lateral thinking to work out how to do complicated things with the limited equipment that is available (you never have absolutely everything you'd like, however rich the lab is!).     So it's been a good week!   

I've arrived!   I got here four days ago and I've been mostly spending my time sorting out the admin - getting an ID card so that I can get into my department, getting a bank account so that I can be paid and (most importantly) getting a new bike so that I can get around.   I went to my new department at the Scripps Institute on Thursday and met the people I'll be working with.   They were really nice and I think that they'll be very encouraging while I go up the initial steep learning curve - it'll take me a while to learn all I need to know about bubbles.   My project is to look at what happens when one bubble breaks into two using high-speed photography.   The bubble goes hourglass-shaped and then pinches off into two drops, each with a pointy tail (like the drop shape that people sometimes say raindrops have - they don't, but never mind).   Then the pointy tail on each then sort of bounces into the inside of the bubble and that's what I'll be trying to photograph.   It sounds like a great project and I'm very excited.    I'm familiar with the photography techniques needed so I can do something useful right from the start, which is great.   I've got a lot of bubble theory to catch up with though...

However, it's still the weekend now so the theory can wait until tomorrow.   I'm going to take my new bike out and explore the coast today - the ocean front is amazing here!