January 20, 2006 – Sampling and Iceberg Central

Today was a gorgeous day so we went out and did the sampling that we canceled yesterday.  It was really beautiful out there and it was actually warm in the sun because there was hardly any wind.  I drove the Zodiac in and out today and that was fun.   Maria handled the sample bottles today.  She sits on the edge of the boat and clamps the Go-Flo bottle to the wire.  The wire is held straight by some lead weight at the bottom.  The bottle is open at the top and bottom as it goes down, so it fills with water.  The first bottle is lowered to our selected depth and then another bottle is added to the wire.  We keep doing this until six bottles are on the wire. We set them from the surface down to 30 meters (about 100 feet). Once they are all down, Maria attaches a “messenger” to the wire, which is a heavy weight that can slide down the wire. When it hits the first bottle it trips the rubber spring, which closes the bottle tight, trapping the water.  The first messenger also releases another messenger which travels down the wire to the second bottle. That bottle is closed and releases another messenger, and so on, until all the bottles are closed. In this way we collect the water from different depths and this can tell us where the plankton and sulfur compounds are most abundant.  So far, most of the plankton and sulfur compounds have been in the top 10 meters of water, since that is where the sunlight is strong enough for the phytoplankton to grow.  The phytoplankton here are growing very thick and so they are cutting off their own light.  At station B where a big bloom is going on today, 99.5% of the sunlight was gone by 12 meters. 

Once the sample bottle is brought back up with the winch, it is removed from the wire.  Maria held the bottles while George attached a tube to get the water out.  We fill several different types of bottles.  The small glass bottles in the rack to the left of Maria is what we collect for DMS analysis. Those are collected first.  We then fill a 1 liter bottle (George is doing that in the photo) which will be used for a variety of measurements, including how much DMSP is there, and how fast the plankton are consuming DMS and DMSP.  After that we collect the rest of the water in a big bottle for analysis of plant pigments (like Chlorophyll and some others).  The pigments can tell us how much phytoplankton is there and also gives us some information on what types are present. 

After very pleasant day of sampling we headed back to Palmer Station.  We went slow because the icebergs are all around the harbor now and their shapes are enthralling.  We had to take some pictures!  Sometimes their beauty takes your breath away.  Today there was one with a beautiful arch in it.  These icebergs come from glaciers along the coast. They break off in huge chunks. Many of the icebergs in my pictures are over 60 feet tall – and they are even bigger underwater (90% of an iceberg’s mass is underwater).  Icebergs vary in color from white to a gorgeous blue.  The blue parts are older ice that has been compressed from the weight of newer ice and snow on top of it.  You can never get enough of these icebergs – I love looking at them.