NOAA Teacher at Sea
Aboard NOAA Ship Ka’imimoana
August 16-30, 2002
Day 12: August 22, 2002
We currently have nearly overcast skies again with rain falling from cumulus and stratocumulus clouds. Our observations at 0800 this morning are:
Visibility: 12 nautical miles (nm)
Wind direction: 200° (direction from which the wind is blowing)
Wind speed: 13 kts
Sea wave height: 4-6′
Swell wave height: 6-8′
Sea water temperature: 27.6°C
Sea level pressure: 1010.0 mb
Cloud cover: 7/8, rain from cumulus and stratocumulus clouds
I awoke last night to swells approaching 8′ and the ship rockin’ and a rollin’! We were in the tail end of a low pressure system with lots of convection (new word from yesterday’s log) causing turbulence in the air and seas. A bottle had fallen over in the bathroom and it continued to roll back and forth hitting the walls for about 10 minutes before I was awake enough to realize the source of the sound; I then climbed down the ladder from the top bunk to rescue the bottle.
Right now, we are attempting to avoid Tropical Storm Fausto, which is currently located to our east and heading 275° (just north of west) at 11 kts. Its central pressure is 994 mb and its maximum sustained winds are 55-65 kts with 12′ seas. The Hurricane Prediction Center’s 72-hour forecast shows 75 kt winds with the possibility of gusts to 90 kts on the 25th with continued movement NW. We should slide just south of the storm and might feel some effects, but they’ll likely be minimal. Aaah, wonderful tropical weather in August! Check out www.weather.gov and view their tropical weather or hurricane page to determine the actual path of the tropical storm.
Science and technology log:
We conducted another live test broadcast this morning with the main Office of Global Programs office and Caption Colorado, the company that will provide captioning for the broadcast. It was 18 minutes long and the transfer was a success. The decision has been made that we’ll do a 20 minute live broadcast tomorrow (Friday) to be received at 4:00 PM EST in the U.S. If you miss Friday’s live broadcast, be sure to contact Jennifer at email@example.com before next Monday to tune into our upcoming broadcasts next week. I’m also anxious to hear from more of you about your interests in oceanography and climatology and the questions that you have for me that I’ll share with our global audience next week. I will do my best to find the answers!
The first official CTD data collection took place last night at 7:30 PM (1930) and a 3:30 AM reading this morning also proved to be successful. I awoke at 2 AM to see if Jason and Paul needed help, but it wasn’t yet time to conduct the test so I happily went back to bed. I did assist with today’s CTD at 12:20 this afternoon. I was so amazed at the entire process. First, the ship must stop and hover for approximately 1 to 1-1/2 hours over the same spot while the CTD sampling takes place. There are 12 depths at which water samples are collected in large cylinders between the ocean’s surface and 1000 m down (See yesterday’s photos for a picture of the CTD cylinders.). Just think of the pressure being exerted on the cylinders at over 3000 ft below the surface! Kirby, one of our two NASA scientists, gave me a styrofoam cup that was intentionally sent down with the cylinders and it’s now a small crushed, but perfect cup. I can’t wait to show my students! The person who controls the CTD from the computer end must work in close cooperation with the winch operator who is in charge of carefully lowering the heavy CTD device into the water and releasing it at different rates of speed to various depths. Any air bubbles that are present must be pushed out of the cylinders so the CTD is first lowered to 10 m, raised to just below the surface, and then lowered again to the greater depths. If the ship’s schedule is not rushed (unlike today), the CTD is lowered to approximately 200 meters off the ocean floor, which could be down to almost 5000 meters, our current depth below this ship! We only had time to lower the sensors to 1000 m today, and then the winch operator raised the CTD to 12 different depths where the carousels (cylinders) were “fired” to allow the bottles to flush and for samples to be collected. Lastly, two samples were taken at the surface. Once the CTD was lifted out of the water, Nadia, my roommate, collected water samples (see photo log) from each of the 13 cylinders to study salinity levels, which tells us something about the conductivity of the water. One reason that this is useful is because the degree of salinity in the water is related to flow of warm and cold ocean currents to and from higher latitudes, and may have been responsible for sudden shifts in climate in the past based on the slowing of our global currents! I have found that it’s incredibly important to ask why each study on the ship is significant to place it in context and to understand the big picture.
John and I met in the early afternoon to create the storyboard for tomorrow’s broadcast. We will highlight the Captain or Skipper of the ship; our Chief Scientist; Medical Officer; Lobo, the Chief Engineer; and Doretha, the Cook. We’ll also have an opportunity for you to win a NOAA T-shirt if you respond with the correct answer to our KA quiz question.
The Chief Scientist and I played 2 out of 3 Yahtzee games tonight just after dinner. It looks like I’m heading to the next round, lucky me! That’s about all that Yahtzee is, luck, but an awful lot of fun. I was invited to ride the RHIB tonight to make our way to a buoy that needed repair. The evening ride was beautiful! There was a full moon with a gorgeous halo around it (good question for tomorrow’s log) and approximately 4′ swells that made it just a bit rocky. There were six of us in the boat. Two scientists hopped onto the floating buoys and started making repairs because there was major damage to the anemometer and the precipitation gauge. One of them started feeling seasick because you’re swaying (just a bit) back and forth and you’re about 8′ above the ocean surface. He hopped off and they asked if I’d like to jump on to help with the buoy repair! Wow! (Mom, please skip this part…I couldn’t help myself.) It was safe, yet thrilling. I helped get the new rain gauge in order and placed small spikes on the top to keep birds from sitting on the edge of the sensor making their own contributions to the contents of the inner gauge. I also helped test it by pouring water through as Dave downloaded data from all the sensors to a computer and checked to make sure they were up and running. I couldn’t believe how lucky I was! I was floating on a buoy in the middle of the Pacific Ocean helping to fix meteorological instrumentation! The ship was all lit up in the distance about ½ a mile from the buoy. We found the exact location of the buoy because of the ship’s radar that spotted it right away and led us to the floating donut. I’ll include some (very dark) photos of this adventure tomorrow.
Well, I’m going to review my notes for tomorrow’s broadcast before heading to bed. It has been another grand day on the great Pacific.
The question of the day for all of you is: What are crepuscular rays? Yes, please consult your meteorology text sitting on your shelf, the Web, or my photo log, to find out. Then, email me to let me know how smart you are!
The FOO’s quote of the day: “Adversity is the first path to truth.”
– Lord Byron
Hope to hear from you soon,