We Blogged It!
Earlier in this journey I introduced you to the SMORE Project. The classrooms involved have just about completed their first samplings along their respective coastlines. SMORE TX has posted their pictures on their blog site (Links listed at the bottom of this homepage). Alaska and Georgia (fieldwork this coming Friday) will have theirs up soon as well.
This first step in our yearlong study has not been without hiccups. Each team has had a learning curve to overcome, including the teachers :D But watching the faces of my students as they set up their “lab spaces” and workstations along the shorelines reminded me of why this is so worth it! Hope you’ll spend some time visiting their blogs!
SMORE students have also sent Tish some questions about the expedition. Thought you might be interested in the Q & A!
Josh: What standard is used to measure salinity?
We purchase IAPSO standard seawater from the UK (Wormley; OSIL Environmental Instruments and systems). They provide seawater standards to the world for calibrating autosal instruments. We take salinity samples from the CTD/Niskins and run them on the Autosal to cross check the conductivity cell on the cast, which gives us a full profile. That way we don't have to measure salinity on every sample.
Manual: Do zooplanktons have any muscle?
It depends what kind of zooplankton you are talking about. Jellyfish do not have a muscle layer, but all of the arthropods and many of the other zooplankton do. I'll pass this question to Deb Steinberg for more detail!
Adriane/Calista: Tish, what has been the favorite thing you have found on this adventure?
The tintinids we saw earlier this week in the transitional zone. Tintinids are ciliates that eat phytoplankton. They have a shape like a champagne goblet.
Danielle: What are plankton nets made of?
Nitex screen or nylon webbing - they do tear very easily and you have to be careful handling them
Margaux: How deep was the ocean when you used the gravity core on the sea floor?
About 4000m deep.
Jesse: How much mud was in the long core? (weight)
One of the long cores brought back about 14 feet of mud. Another was about 4-5 feet of mud. The diameter of the tube is about 6 inches. If you can calculate the volume of that cylinder, you can then convert to metric and use the density of the sediment (about 2 g/cm3) to get the weight.
David: How did the Medusa (plankton) get its name?
I don't know the actual origin of the use of the word (I'll ask Deb), but the Greek Medusa was a woman with snakes for hair, right? I think the jellyfish just looked sort of like that, with their long tentacles
Chief Tish has also sent a new satellite image today of their current location, as the search for the “elusive” DDAs continues! She writes:
“We are heading toward some blue water... hopefully.... to do a drift station there (#24 on the map). We have done the red part of the track and hope to do the white track before heading for the barn on Oct 8.”
“…Seems like the cruise is going to be over before we know it though. We've started watching every hour much more closely - making decisions about whether adding an operation now will take away the time needed for doing something we want to do later. And we still have not found our DDA blooms (diatom diazotroph assemblages - the algae that have symbionts to make nitrogen for them). They are around in low numbers only - even in the places we thought they should be. Something interesting going on here.... “
“Today we were at Station 23 in the outermost part of the plume (detectable by satellite) and the water was still 32 ppt. All the river color was pretty much gone (it looked blue blue!), but the salinity was still low - suggesting that the plume may be bigger than the satellite can see. I need to look into how this new Aquarius salinity satellite works - I don't think it uses the same technology as we have used before - so maybe it will do a better job and prove our case about the scale of the river plume. Regardless, the chlorophyll in the plume out here is quite low - but the bacteria seem to be cranking. Interestingly, the pCO2 is still (just) below saturation, so it is still a sink, albeit a small one by now. “
Coming in the next post- “featured creatures”!
Question of the Day
- Do the bacteria in the water make us sick?
Only a few of them. Bacteria are in every habitat on Earth, growing in soil, hot springs, radioactive waste, water, as well as in organic matter and the live bodies of plants and animals. Bacteria recycle nutrients, with many steps in nutrient cycles depending on these organisms, such as nitrogen fixation.