Monthly Archives: December 2013

Flushing the loo in the Southern Hemisphere

Hurray! We just crossed the equator into the Southern Hemisphere! Everyone has been waiting for this moment in the computer lab, crowding around the screens as the Latitude changed from N to S through a number of zeros. There was no red line to cross or a welcome sign floating. Just an imaginary line imposed on the surface of the vast ocean and us with our numbers.

Roger Revelle crosses the equator!

Roger Revelle crosses the equator!

The ocean has been relatively calm as if welcoming us with a warm embrace. Or perhaps it is just a front, beckoning us deeper into the heart of the ocean only to swallow us into the storm of storms (Luck seems to be on our side looking at the sea state predictions – guess Poseidon likes us). We are approaching our first waypoint where we will survey the area for an ideal location for a gravity core so hopefully Poseidon stays with us. So, now that we are in the Southern Hemisphere, which direction will the flush of the loo go? Clockwise or Anti-clockwise?


Joyce’s birds & a contest

As Joyce pointed out in her post the sounds of the multibeam and chirp system can be heard in most places on the ship and are now are constant companions.  I was able to record the sounds in a relatively quite passageway on the ship (using my cell phone believe it or not).


This image shows part of the waveform of the audio I recorded.  There are three pulses, the first and last are the Knudsen chirp and the middle pulse is the EM122 multibeam.

Below is the full audio, 3 chirps with the multibeam between chirps 1 and 2.

The multibeam can be tough to hear because it operates at a higher frequency than the chirp, so I slowed it down by 4x.

Here is the chirp, also slowed down 4x, just because it sounds cool.

And now for a challenge:  Take the mp3 with the chirp and multibeam pulses from above and figure out what frequencies the chirp and multibeam operate at.  The source is noisy so lets say that you need to be within 20% to get the answer right.  First one to post the correct answer wins a tee-shirt.

Robert Petersen

Fine print:  If you already know the answer then you can’t play.  You need to use the sound file to get the answer don’t look up the specs.  Also I’m in international waters so I don’t have to comply with any of those annoying rules that ‘man’ wants me to.


The birds are singing

I woke up to the sound of a bird chirping. Warned about how loud this bird might be, it was actually rather pleasant. At a lower frequency, another bird sang with softer but quick screechy tones.

Mt Robert

Mt. Robert has a prominence of roughly 700 m

Jam packed with action, the computer lab was bustling with people making sense of the 15 screens in front of them – it is really just five (maybe). Oh a seamount! Amidst the happy chatter and chirping, we named it Robert. The bird was not happy about Mount Robert and lost its bottom tracking. After freaking out for a while, it finally found the bottom clearing Mount Robert.

Pseudo-Side Scan of Mount Robert

Pseudo-Side Scan of Mount Robert

About 6 hours later, the birds found a hill of roughly 50 m and it was named Soli Hill, after Soli, who first noticed the anomaly. More appropriately known as Soli Hills, it turned out to be more complicated than it seems. Well, all in all, the birds are happy and chirping away.

More about the birds later.

— <a href=”>Joyce</a>



You want to make God laugh? Tell him about your plan

We’re finally underway, some 50 nautical miles southeast of Sri Lanka, and something that’s quickly become apparent is that when at sea only a plan that can change is a good plan.

It’s our intention to sail for the 90E ridge and collect some gravity cores and perform a CTD cast (more on this later) so our resident paleo-climatologists can have some fun. As we sat in port we schemed, and plotted tracks, and thought, hey, we have more than enough time to do this great work. However, the fuel barge was late (because it runs on island time we were told) so we left port about 4 hours after scheduled. Then as we made a left turn around the corner of the island a cross current reduced our ship speed from a planned 11.5 knots to 9 knots for about 4 hours and we’re still unable to do more than 10.8-10.9kts.

None of this is a deal-breaker of course, but the only certainty here is change. We’re keeping an eye on the ETA to our next way point and constantly readjusting what we expect we’ll have time to do. Ship time is a valuable commodity in science. As conditions change we try to peer into the future, we adapt with an eye on how to use this limited resource in the most impactful way, that is at least, until the next unexpected curveball.

Diego Melgar


Hi MIST Followers,

We are off! We left port last night around 10 pm after refueling was completed.  It was sad to say goodbye to Sri Lanka, but we are excited to be underway and to begin our science mission!


Before we left the science party had a last dinner on land together at Amaravathi, a popular local restaurant in the Kollupitiya area of Colombo that serves Sri Lankan and Indian food. It was fun to get to know everyone, and the food was delicious. Continue reading

5 days in Sri Lanka

Hi MIST Followers,

We boarded the ship yesterday, and are all settled in. Today we are mostly preparing to leave for tomorrow – a lot of small things are still being ironed out, but we are all excited and ready to go!

I was lucky enough to travel around Sri Lanka for a couple days before boarding the ship. It is truly an amazing country – there is so much variety and so many different places to see, all packed on a small island. I think I could have stayed for 2 more weeks and not seen half of what I would have liked to! Continue reading

Hold Fast


One of the things about life on board a ship is that no surface stays horizontal for long.  If you are a landlubber like me this means paying special attention to where you put a pen, or worse your coffee cup.

The ship and the crew, however, are well used to life at sea, and have modified their world to account for when gravity doesn’t point “down”.  All the chairs in mess, the labs and around the ship are heavy and have no-slip rubber feet attached to the legs.  Shelves and desks have raised edges to prevent things form sliding off.  There are a few other techniques for keeping things in their place when they would otherwise be thrown to the floor. Continue reading

Welcome Aboard

In one of those twists of fate we landed in Sri Lanka to board the Revelle on the  9th anniversary of the Indonesian earthquake and tsunami. As we headed out of the airport the PA system announced that a minute of silence would be observed. The buzz of the terminal deadened as everything stopped and through the haze of jetlag it suddenly hit me, we’re here.

A moment of silence at the Colombo airport commemorating the 2004 Indian Ocean tsunami

Sometimes life has a certain symmetry to it and the mind cannot resist making connections and seeing patterns. Not that there’s a grand design here, it’s just curious how things work out. It’s the anniversary of the earthquake that stirred in me the curiosity of what makes the Earth tick. It is on this day we’ve come aboard Revelle with the intent to peer down through the ocean at the Indonesian subduction zone and unravel some of its mysteries.

There is so much to do with preparations aboard, getting all our equipment in order and generally getting accustomed to the ship that there’s been little time to marvel at the opportunity we’ve been afforded. It’s getting late and as the ship quietens and only the creaking of the mooring lines can be heard outside there is space for this simple yet powerful reflection, that amongst the angst and anxiety of all the new things we have yet to learn, we can’t wait to get going.

Diego Melgar

scripps oceanography uc san diego