Thursday, July 24, 2014

Measurements with the Salinity Probe


This week I took my first measurement using the circuit I built and the code that I wrote!

Step one was to make salt water.  Not all that difficult to do.  I researched the appropriate salt content of ocean water.  Get some salt and some water of course.  Calculated and measured the exact amount of salt needed. Boiled water… had some tea.  Used the boiled water to dissolve the salt and put the salt water into a giant bucket.  

 



Step two - find a new bucket because the one used has a giant hole
 :(





Step three- clean split water



Step four- place the probe in the bucket of water and run the program. 

Step five- sit back down at the computer and resolve all error messages.

Step six – interpret findings.  


Step Seven will be to trouble shoot and eventually calibrate the values received with the true salt concentration of the water. 

Yay Science!

Tuesday, July 22, 2014

SCUBA! Magnetic Island

For the sake of science, I sacrificed my free time last weekend to expand my knowledge of marine biology through scuba diving. In order to achieve this I took an online course and spent Saturday and Sunday completing my open-water diving certification through Pleasure Dives at Magnetic Island.

I left on an early morning ferry from Townsville to Magnetic Island.
Sunrise over Magnetic Island
The first day I spent mostly in the pool and I did one dive in a shipwreck at Geoffrey Bay! How exciting to dive in the ocean for my first time! It was chilly!! Even with a wet-suit I was shivering and cold most of the day. But I braved winter on this tropical island for the sake of science, so that I will be better prepared to collect microalgae samples from the deep.

The next day I did two dives in the morning at Alma Bay, then we took a break before completing my open-water certification and doing my final dive at Geoffrey Bay.

Here is a brief video with a panoramic view of Geoffrey Bay:




But first I took a walk to collect some algae samples from the bay at low tide. Here is one of my sampling sites:

Algae Sampling site, Geoffrey Bay, Magnetic Island
While I was wading in the water collecting algae, I had a close encounter with a group of sting-rays! I managed to capture one on film before fleeing for my life!

Sting-ray
I was told that this was not sting-ray season, but I saw a number of sting-rays including during my dive. The locals told me that even in "off-season" there are always sting-rays in this bay.

And it was a good thing I fled the water, because a moment later I saw a number of shark fins!! I tried to get some footage. It is a little shaky because I was so excited and was too busy watching them with my eyes instead of through the camera.



After being frightened by the sharks, which I later found out are blacktip reef sharks, I decided to head to higher ground and make friends with some more congenial animals. I am speaking of course of the rock wallabies.






Finally I donned my SCUBA gear and headed back into the water for my final dive to complete my open water certification. I also obtained some algae samples for lab work while I was down there!

Here are some pictures from the experience:





Nudibranch




All in a days work! The next day I took my samples back to the lab and took some photos and video under the microscope.


(In the above video, the brown spinning things are dinoflagellates, and the longer slow moving things are diatoms.)

Monday, July 21, 2014

Salinity Probe



Salinity Probe

The Device I am working with is a salinity probe that is used by the lab to measure how much salt is in the water.  The probe first calculates the output current from the device using a known resistance and voltage measurement.  Since V=IR, once the voltage drop is received, the current can be easily determined.  In addition to the initial voltage reading the probe must
do three other voltage readings, one to measure the final voltage and two in the middle to measure the voltage drop across the water.  Because the water is a conductor, the resistance in the water can be determined based on the voltage drop.   This resistance is then calibrated to the salinity of the water taking into account the temperature and area of the nodes on the probe.  (Picture of the probe below)



My Goal in this project is to write a program that extracts and records data from a salinity probe so that it can be mounted on a different device.  Currently the program is run through a different system, using a different programing language.  Making the device run using the Arduino’s language would make it compatible with other measurement tools created by the lab. (Picture of the test probe below)




Last week I have made great progress in achieving my goal.  The first step was to disconnect probe from its original home (image below) and put new connectors on the existing device.  I was able to do this by soldering new connections onto the wires so that I the pins were compatible with a breadboard.  



I have also been working on writing the program so that I can run some tests and have connected all necessary pieces to the breadboard and Arduino chip.  (Image below)


Well.. I better get back to work!




Wednesday, July 16, 2014

Airlie Adventures

Last weekend the fearless Kate and I drove south to Airlie Beach and the Whitsundays to do some more investigative ecology journalism. We decided to sacrifice another weekend of our free time and dedicate ourselves to the pursuit of science Down Under. All for science of course!

We were advised by Columbia University's last group of seafaring scientists (Jeff Wuebber & Tiffany May) that the Derwent Hunter was an ideal choice of a sail boat for sampling the local ecology and observing abiotic water factors such as turbidity, salinity, and temperature. As soon as we boarded the ship and news got around that a physics teacher and nautical engineer was aboard, the crew immediately detected Katelin's navigational prowess and set her to work. She manned the boat and they couldn't have sailed it without her!


It was quite cold (about 19 degrees Celsius) aboard the ship hence the wrapping in sweatshirt and towel. In typical Australian fashion however, no shoes were allowed aboard the ship. While Katelin navigated and took temperature readings (cold) and turbidity measurements (calm) through her powers of observation, Justine was free to explore the local ecosystems.

Their first stop was "One Foot Island." Geared up with a snorkel, wet suit, and sea-noodle (more durable than your typical pool noodle!!) she braved the chilly (22 degree Celsius) waters and documented the wildlife.

One Foot Island (really a sandbar)

Fearless Scientist with Sea-Noodle
It was there that Justine and Katelin observed SEA TURTLES! Specifically the green sea turtle. More than one was observed, but Justine spent a great deal of time following one turtle in particular. The following is rare amazing footage of this magnificent creature.

Green Sea Turtle Swimming

Green Sea Turtle Swimming

Green Sea Turtle Breathing

Green Sea Turtle Swimming

Green Sea Turtle Getting Cleaned by Fish at a Cleaning Station

But wait! There's more! Justine also got VIDEO footage!





After the sea-turtle adventures Justine and Katelin set sail for a neighboring island, Black Island. Once more Justine donned her snorkel, this time she went without the sea-noodle, and explored the reefs around Black Island. No sea-turtle sightings, but she got some gorgeous views of the reef and fish. Take note of the varying colors of the corals due to differing species of dinoflagellates!











And a few more above water photos from Black Island...




And some fine pictures of the Derwent Hunter, a ship with quite a history! And now we are part of it!



 
 
The two bluey teacher-scientists had an amazing day with many new and important discoveries. Their bond as scientist-partners was greatly deepened that day.


Sunday, July 13, 2014

Lab Update: Observing Live Specimens

The first step in observing phytoplankton from the reef is to collect the samples. Later this week I will be doing some field work and collecting original samples. Today's samples were collected from coral reef tanks outside our lab that are used for teaching purposes. Previously I showed you some images from prepared slides. Today I will be showing you how to observe live microorganisms under the microscope using an inverted microscope.



These images were taken not with the digital camera connected to the microscope and the laptop, but rather by simply holding my own digital camera up to the microscope eyepiece. I learned this technique from my students, who often use their iPhones to take fairly decent images of their microscope observations by simply holding the camera lens up to the eyepiece.

Foraminifera 40X
Diatom 40X

Diatom 40X

Here is a video I filmed with my camera of a diatom gliding through the water:
 
 


 

Thursday, July 10, 2014

Maggie Island

Last weekend, Katelin and I ventured to Magnetic Island, or Maggie, as the locals call her.

I felt that for the sake of science I should investigate the local algae and check out the Great Barrier Reef, or a small part of it anyways. We hired (rented) snorkel gear and hiked to a remote beach that was inaccessible to cars. There we ventured into the blue waters. I used my underwater digital camera to document some of species we saw.