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PhilGChapman
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Glad it was of interest Kevin. I thought the pieces were well written and clear; and I always appreciate historical context.
Having such a collective resource from which to draw is a nice idea. My main (and only minor) suggestion for improvement would be to have a consistent referencing style, and one or two graphs (e.g. N. Hemisphere temperature reconstructions near the start) don't appear to have a reference. But nice work, well done!
Just noticed fissures starting to open up in the Laptev Sea. Today's 'worldview'
Lloyd, going a bit off topic here, but... Mediterranean overflow water (MOW), i.e.that which enters the Atlantic, doesn't move to the bottom of the Atlantic (at least not before it becomes north atlantic deep water and flows south), but rather sits mid-depth (it may be high salinity but is also warm). These schematics show this somewhat: http://bit.ly/14p6zjC http://bit.ly/14iHO8q The formation of deep water in the north Atlantic isn't entirely straight forward. Unfortunately I recently missed a talk on Labrador sea water formation, the abstract for which I include below: "Under the harsh winter conditions of the north-western Atlantic Ocean, surface water in the Labrador Sea mixes with water from deeper layers to form a homogeneous water mass known as Labrador Sea Water (LSW). The amount of LSW formed displays a large interannual variability with a depth of convection ranging from only 200m to over 2000m depth. In order to understand the driving mechanisms behind this variability, we need to understand how the ocean and atmosphere drive and limit convective mixing in this region. I will zoom in onto two aspects that are important for convective variability: (1) the roles that three different mesoscale eddies play in the restratification season after deep convection and (2) the way in which the fresh surface layer inhibited deep convective mixing in the particular case of the 1969-1971 period. The first item is studied using the MITgcm model in a highly idealized regional configuration of the Labrador Sea, where we found a dominant role played by one particular eddy type. The second issue was studied using in situ data taken from an ocean weather station in the central Labrador Sea. The analysis shows that the role played by fresh water in the surface is more complicated than commonly assumed, with a feedback mechanisms which actively decreases the surface heat flux as long as deep convection is inhibited."
The Laxon et al. paper is here - http://www.personal.soton.ac.uk/pgc1g08/grl50193.pdf @Djprice57 There is a negative feedback following large ice loses in the melt season when the temperature starts to fall. Ice acts as an insulator on the surface of the ocean, so where there is little or none, heat is lost relatively rapidly leading to relatively large increases in ice formation. As for your new metric, it made me smile, but I'm not sure what extra it could usefully tell us :)
The leaked version seems to be missing the figures, so I've emailed a copy to Chris. I'll upload it to a server somewhere for wider access when I get a moment.
And bear in mind one of the paper's comclusions is: "The rate of decline in autumn ice volume that our data show (~800 km3 a-1) is 60% higher than the decline in the PIOMAS integration analysed [by Schweiger et al. (2011).] This is further evidence that the PIOMAS estimates of autumn volume loss are conservative."
Thanks so much Chris. As I'm at the Oceanography Centre I would be looking more towards the phytoplankton blooms than the land plants and have thought about that. Increasing open water does appear to be leading to much greater primary productivity in the Arctic, with in all likelihood shifts in species composition, possibly opening up of fisheries and changing linkages with the benthos. Also thought some about the communities directly associated with diatom production on/in the ice itself, but don't know much about this. At a push I might be able to blag my way up to Svalbard ( http://www.arctic.ac.uk/infrastructure/research-station/ ) - not sure yet what instrumentation/boats might be available though.
Toggle Commented Feb 4, 2013 on Open Thread February 2013 at Arctic Sea Ice
Hi All, Slightly off topic, I wondered if I could seek out some suggestions. I'm doing an undergraduate masters course (MSci)at the National Oceanography Centre in the UK and am now thinking about what I'm going to as a research project. I have a broad interest in what could be called Earth system science, with perhaps an emphasis on photosynthesis, primary production and molecular biology. I have however become more and more taken with the cryosphere and the apparent rapid changes in the Arctic in particular. So much could (is!) changing there and fast, with very little known about much of the basic ecology. What would people suggest as possibly important and/or interesting things to study at the moment, considering I'm unlikely to be able to hitch-hike a cruise there (but could possibly travel this summer). Thanks in advance, Phil
Toggle Commented Feb 4, 2013 on Open Thread February 2013 at Arctic Sea Ice
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Feb 4, 2013