Steaming westward in the Atlantic

July 15, 2010

Location: Mid-Atlantic

Coordinates Lat / Lon: 36*48.4384'N/ 43* 49.5150' W
Air Temp: 23.80*C /74.84*F
Humidity: 80.8%
Sea Surface Temp (SST): 24.92*C / 76.86*F
Salinity: 35.62 psu

Depth: 4465 m / 4.5 km / 2.8 miles

Today was our second day in transit so, while we had downtime, samples are still being processed. Paola Sanchez, PhD researcher, is pictured at the top "picking" samples for foraminifera.

We started our day off in a new time zone (GMT--2). It was nice to have the extra hour. Daylight is an interesting factor when you are on either edge of a time zone. Last night we were still in GMT-1 ( On the map find the correct column and note that the zone “bumps out” around the Azores. We were at the far western edge of the time zone – this is an interesting place to be because while our length of daylight is the same as all other locations on the same line of latitude around the world, the clock hours of sunlight are shifted.

Huh? Consider the US Midwest today, July 15. Here are three cities within the same time zone that have very similar latitude. The cities are listed from their locations east to west across the US. They are ALL in the same Central Time (Daylight Savings) Zone.

Location: Sunrise / Sunset

- Chicago, IL: 5:29 am / 8:24 pm (eastern most)
- Davenport, IA: 5:42 am / 8:34 pm
- Des Moines, IA: 5:53 am / 8:47 pm
- Omaha, NE: 6:04 am / 8:55 pm (western most)

So our sunrise and sunset times have been shifting each day throughout our journey westward from the Azores – later sunrise, later sunset. Still, yesterday when it was announced that the nighttime plankton tow would be done at 10 pm, we did not think twice about it. But when 10 pm rolled around it was still light out! So in the fading light, the tow was done and it was dark by the time they were finished.

What did they find? The science team aboard the R/V Knorr is focused on ocean floor sediments, specifically fossils that indicate the relative temperature of the ocean water when they were alive. This cruise is focused on paleoceanography. They are not focused on biology of living organisms. So the first plankton tow resulted in the capture of lots of “things”. Some were “freaky” looking, all were smelly! The ones that were definitively identified were shrimp and foraminifera. If they do another plankton tow, I'll pin down some specifics for you! For now I can tell you that the organisms we saw were largely transparent and difficult to see when they were still. Luckily some wiggled and others zoomed through the field of vision.

We did not see all of the organisms in this image but it gives you an idea of what we were looking at.

(Right) Sean Guss is pictured holding the plankton net he pulled in at the
end of the tow.

(Above left) Marti Jeglinski and Kathryn Rose are emptying the net of its catch - smelly!

(Bottom right) Petri dish with the organisms caught in the tow. They looked like a brown-green cloud in the water.

Last night we saw a dolphin hopping the waves and heard that some people had seen flying fish!

Tonight, on our way up to the top deck for sunset yoga and pilates I noticed a brown blob in the water...and then another...and another! Seaweed...

...and I realized where we are...

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