Friday, April 27, 2012

Sediment Trap – analysing the data gathered

Scott Nodder and Lisa Northcote are analysing the Marine Snow that was collected in the sediment traps we retrieved on the Tangaroa. Each sediment trap bottle had been “fixed” with Mercuric chloride as part of the sample gathering process. This means each sample hasn’t changed. No bacteria etc has grown to mess up the data. Mercuric chloride halts everything and is a chemical that has to be used with great care. (Nasty stuff!)
Back in the lab, Scott takes each sample and under a microscope looks for all zooplankton. 
Scott Nodder sorting Sediment trap sample
Copepods, Amphipods (like little sand hoppers) Little jellyfish, Polychaete worms (segmented worms), Bristle worms, Pteropods (sea butterflies) Salps, Isopods (slaters) and little starfish were all types of zooplankton found today.  These get put into little specimen jars.
Samples of Zooplankton- note the size!


Lisa Northcote then takes the Marine Snow and divides it into 5 sample bottles for further analysis.

The samples are evenly distributed through a sample divider that has been designed especially for Sediment Traps.
 

Friday, April 20, 2012

Google Earth

Google Earth has an application that allows you to monitor the Argo network in real-time. (Info on wiki).
Here is a screenshot of all the Argo Floats down south, their numbers (and the trajectory of WMO 5903880).

Thursday, April 19, 2012

Argo Float Trajectory #2

After being side-tracked about the Coriolis effect, in this post I'm returning to the Argo Float mentioned- WMO5903880.
Here is the data that this Argo Float has relayed back so far. It's first profile was on 17 February, where it did a sample at shallow depths. Since then it has had 9 cycles.
" These data were collected and made freely available by the International Argo Program and the national programs that contribute to it.  (http://www.argo.ucsd.edu,  http://argo.jcommops.org).  The Argo Program is part of the Global Ocean Observing System."

Argo Float Trajectory

Back in February, I was in Bluff helping 'wake-up' and load 20 Argo Floats on board the 'Spirit of Enderby'. They were going to be deployed on Gareth Morgan's 'Our Far South' expedition.
I've been keeping an eye on where they are and what info they are telling us. Here is the trajectory of Argo Float WMO 5903880

See how it is heading off to the right (west to east). This is due to the Coriolis effect. In the Southern Hemisphere winds and ocean currents generally move in this direction and the opposite direction in the Northern Hemisphere.

I've been 'myth bustered' about the Coriolis Effect. I always thought that water goes down the sink differently in the Southern Hemisphere to the Northern Hemisphere since the Coriolis Effect acts in an opposite direction. The truth is that while the Coriolis Effect is real on a macroscopic scale (as with ocean currents and hurricanes), it's very weak on small scales, as in a sink or toilet bowl. Initial conditions, especially the direction the water enters the basin, are more significant than Mr. Coriolis' effect and can easily overcome it in most cases.

Monday, April 16, 2012

RV Tangaroa- the Galley


A short video about the Galley on the RV Tangaroa. Click on the picture for link to youtube clip.

RV Tangaroa- the Engine Room


A short video about the Engine Room on the RV Tangaroa. Click on the picture for link to youtube clip.

RV Tangaroa- the Bridge

Thursday, April 12, 2012

Baring Head

Baring Head is on south coast of the North Island. You get there by driving out through Wainuiomata to the coast.
Baring Head - Niwa
It is exposed to strong southerly winds that haven't been in contact with land for at least 5 days- making it a terrific location for Niwa's Clean Air Station. Niwa has been monitoring atmospheric gases here since 1972.Baring Head is an internationally recognised site that contributes to global scientific studies into climate change and our impact on the earth’s atmosphere.

NIWA's Baring Head monitoring station
Someone from the Atmospheric Research Team comes out every week to check on things and take readings. Today I was lucky to head out with Technician Matt Evans. He got me helping take an air sample, drying glass beads that had frozen up for reuse in a measuring instrument and record results off tanks.The Baring Head site has 4 buildings. One looks like an old WW2 bunker that has been sealed up. There is also a large tower with instruments mounted at the top. I was slightly relieved that we didn't need to climb up there to check on things. Pretty wild out here!
Matt Evans and air tanks.





Sample air lines are mounted high on a mast and air is pumped through the air lines to tanks. Equipment here take continuous measurements of the air.  









We also had 2 glass (almost balloon-like) flasks to take a sample of air outside in the southerly. To take the sample, we had to go outside facing south and hold the 'glass balloon' up, hold your breath, and open the valve. There was a hissing sound as the vacuum was filled and you then had to quickly close the valve- All took less than 10 seconds.
One of these is taken back to Niwa for testing. The other is sent over to the Scripps Institution of Oceanography (SIO),
University of California at San Diego.


35 knot southerly outside- relatively calm!

Here in this small video, Dr Katja Riedel, Tropospheric Chemistry, explains what they do out at Baring Head.

Atmospheric research at Baring Head from NIWA on Vimeo.

Baring Head Lighthouse (1935) Wellington Heads in background to right.

Tuesday, April 10, 2012

Beaufort Wind Scale

The Tangaroa is up north at the moment, taking many water samples at various depths in the East Auckland Current. They had some pretty rough weather with Cyclone Daphne near by. Winds up to 43 knots- I feel sea sick just thinking about it!
The Beaufort Wind Scale is named after Sir Francis Beaufort, an admiral in the British Navy. He developed the scale in 1805 to estimate wind speed by noting how sails move in the wind.


Here is an interesting link

Interactive Weather and Wave Forecast Maps

 

Monday, April 9, 2012

Belmont Regional Park

Had a stunning day off with a walk up in the Belmont Regional Park from the top of Takapu Road over to Dry Creek (bottom of Haywoods) Breath-taking (maybe a bit because of the climb!) views of Wellington, the Hutt Valley and Porirua area. The Kaikoura mountain range could be seen clearly in the south and over to the west, Stephens Island. Belmont Regional Park has interesting history. Early Maori found 2 major routes to link Wellington and Porirua harbours. In the 1850s a dray road- the Old Coach Road was developed along one of these major routes and coaches from the Hutt used this route to Pauatahanui until the mid 1880s when it was replaced by the Haywoods Hill Road.
During World War 2 there were 62 concrete ammunition magazines built to store army munitions (mostly for the Pacific campaign). These were spread out to look like a chicken farm from the air! These days they are used mainly by sheep and cattle for shelter- it can get pretty wild and windy up here.



Wellington Heads
 Boulder Hill aptly named after the remnants of greywacke here- only area in all of  Belmont Regional Park with these boulders. A good climb up to be rewarded by the sweeping views.
You cant beat Wellington on a good day!