NOAA Teacher at Sea
Onboard NOAA Ship Ronald H. Brown
October 2 – 24, 2001
Mission: Eastern Pacific Investigation of Climate Processes
Geographical Area: Eastern Pacific
Date: October 13, 2001
Air Temp: 19.7 ºC
Sea Temp: 19.9 ºC
Sea Wave: 3-4 ft.
Swell Wave: 3 – 4 ft.
Visibility: 8 – 10 miles
Cloud cover: 3/8
Energy from the Sun
The sun is the source of all energy on the Earth. The sun gives us this energy in the form of light and heat. Where does all that energy go? Why? How can it be measured? These are some of the questions many of the scientists on board are asking.
Toby Westberry and Olga Polyakov are scientists that have 2 instruments to help them understand how solar energy behaves in the ocean. The first is the SPMR which is a tool used to measure how much light penetrates the water. The more light = the more heat. You can see in the photo that it is a small black device attached to a long cord.
Toby and Olga lower the SPMR over the side and let it sink to 300 meters. Then they reel it back in just like a fishing pole. It tells them the “color” (wavelength) of the light at different depths. They do this over and over again in different locations in the ocean. Why? We know that the ocean water is not the same temperature in all places on the planet. Can you think of why this might be?
Well Toby and Olga know that there are tiny living organisms in the ocean that play a role in how warm or cool the temperature is. They are called phytoplankton. It seems that the more phytoplankton there is near the surface of the water, the more heat is trapped there.
Here’s an excellent explanation from Mrs. Richards of what’s happening that might help you to understand the process:
Imagine a nice clear swimming pool. The sun’s heat energy can penetrate all the way to the bottom of the pool because the water is so clear. Whatever heat energy hits the pool will be dispersed throughout the water somewhat evenly. Makes sense, right?
Now imagine that the pool has a layer of scum and algae at the top. Face it, you just haven’t done a very good job at cleaning the pool, and your allowance just isn’t big enough to make the job worthwhile. Now, the sun’s heat energy can’t pass all the way to the bottom of the pool because the scum is blocking the light. The very top of the pool water is going to capture almost all of the sun’s heat energy, and the bottom layers of water will be darker and colder. Imagine how the temperature of the water will be affected by the amount of scum in the water.
Knowing how much phytoplankton is hanging around would certainly help understand how the sun’s energy is being used. For this experiment they use a CTD. (Boy they sure use a lot of abbreviations for things!) This instrument is really big and needs a big machine called a winch to lift it in and out of the water.
It has 12 tubes that fill up with water, each at a different depth.When the CTD is back on the ship, Toby and Olga fill labeled plastic bottles with the water.
Then their work begins. First they run all the water samples through a filter to figure out how much phytoplankton was in the sample.
Remember each tube on the CTD took in water at a different depth. So each bottle will tell a different story. They use this information to create a data graph which is used with other information to tell how the sun is heating the ocean.
Sea birds! I don’t know how they do it or where they came from but all of a sudden 5 “boobies” showed up over the ship. What was amazing is that they hardly ever flap their wings, yet they fly as fast as the ship. The ship is moving forward at about 10 miles an hour and has big engines to push it. These birds just seem to glide along over us. Beautiful!
Question of the day: What is an updraft and what causes it?
Keep in touch,