Submitted by Anonymous on Tue, 07/31/2012 - 09:43
Forums
High Arctic Change 2012

Hello Dan, my name is Maddalena, from Italy. I am a Science Teacher in the Italian High School, my subjects are Earth Science, Biology, Chemistry and Astronomy. Currently, I'm attending the new on-line course of polarTREC (summer edition, of course), and I'm very pleased to be involved in reading your journal. What a wonderful experience is your expedition! At the moment I've read just your first eight posts, but I've noticed your last contribute, related to "record at Mooring C". I'm very engaged and curious about the secrets of the graph. So I have some questions for you: 1- Is it possible to have the graph in high resolution? 2- The colors don't fit on the pc screen, for example the "gray" appears probably light blue, doesn't it? 3- Is the temperature anomaly on 12-13th July related to the weather conditions? for example clouds "blanket"? (do you hear my old brain circuits making screeching noise?). Say me only yes or no... I prefer to try again...

That's all for the moment, a huge "ciao" from Florence (37°C today...) Best wishes, Maddalena

Tue, 07/31/2012 - 14:17

Dan Frost

Hi Maddalena,Thanks for the inquiry! I've posted a higher resolution graph on the 'resources' section that should help with the colors etc.. The gray (hint here) BOR is right behind the TOR purple with only a bit showing as they are almost identical throughout the record. As for the temperature anomaly between the 12-13th of July I would categorize what we are seeing as based on a set of environmental conditions but not specifically cloud based blanketing. At your request, I will keep my response to a simple 'keep looking around..." : ). I can add another graph of instrumental data from outside the lake, that I may have mentioned earlier in a post, later if it may help...
Glad to have another curious person looking at the data!
Sincerely,
Dan

Wed, 08/01/2012 - 09:03

Anonymous

Thank you Dan for your reply.I've downloaded the graph, but I still have some problems in understanding the right days positions on X-axis.
Anyway, I try again (hope this isn't boring for you). On 12th July, the lake surface appears about completely frozen, suggesting a lower environment temperature. The ice could be a sort of thermic insulator, maintaining the water temperature nearly constant. However, I'm also looking at the "quality" of ice: it looks as if it begins to melt, and in fact some days later the lake surface is completely free from ice coverage. Alternatively, the ice could also continue to increase its extension on 12-13th July, releasing heat to the environment around (and consequently rising of temperature).
What about my brainstorming?
Am I near to bang the target? Or have I still a long way to go?
I'm carry on reading your journal...
Ciao!
Maddalena

Sat, 08/04/2012 - 06:25

Dan Frost

Hi Maddalena,Sorry for the delayed response. Today has been the first day in a few I've been able to spend a good amount of time connected to the web. The ice present is important in that my interpretation suggests that it is what keeps the uppermost water column temp. probe from getting much higher than 2.25 degrees C. You're right about it insulating those upper waters from mixing in the warmer air temps. At this point though, the extent of ice is continually decreasing and what we are seeing in the plume cam is the brittle ice floating back and forth with the wind across the lake (toward the last days of its presence at all).The eye-catching part is that the mid-water column probes all rise in temperature by about a degree. I won't give it all away just yet, so...the ice keeps the upper waters cold but what could possibly warm the mid-waters by its now active presence in the system?
Hope all is well in Florence!
-Dan

Mon, 08/06/2012 - 01:04

Anonymous

Mumble mumble...
the last try is coming soon...
In the center of Italy the temperature is so high, a long series of anticyclones coming from Africa blow hot air, we haven't had rainfall since last June, a so long drought period...We all are worried about fresh water reservoir.
This phenomenon is related surely to global warming and the problem of desertification in the Mediterranean regions, another reason for studying polar science also in our country.
How I envy you!
ciao a presto (=see you soon)
Maddalena

Sun, 08/12/2012 - 18:11

Anonymous

Hi Dan,This is Julia, and I'm also taking the Polartrec course. I live in the Adirondack Mts. of NY, and am a biology/environmental science teacher. Geology is certainly not my area of expertise, but I do love lakes. I'm finally getting caught up with your journal, and this puzzle was very exciting to me! I wanted to raise my hand and say "I know I know!" But I'm not sure I do. Here's what I first saw when looking at the data/photos, which you've confirmed. The ice is going out, and the water keeps flowing in. The ice, now fairly rotten, blew back towards the inlet on July 12. This caused the surface water to skip its daily fluctuation. My guess is that the water coming into the lake is a little warmer, since it is shallow and mixing constantly. This water, being a little more dense as it is still below 4°C, naturally goes under the ice, which doesn't allow the normal mixing. Hence the middle depth water is suddenly warmer. Am I close? The interesting thing is that the next day, everything is rather flatlined... I will ponder that one.

Thu, 08/16/2012 - 03:58

Dan Frost

Hi Julia,Thanks for the questions and I apologize for the delay (been crazy with the transitions etc.). You are on to it! Yes, Linneelva (the meltwater stream entering the lake) is contributing the warmer waters, laden with sediment that are denser and entering the lake system as an inter/under-flow. Accordingly, they are triggering temperature responses from the middle probes and not the upper-most as the ice moved back over that section of the lake. Water being most dense at 4 degrees C (from both directions) plays a part here and the colder water on top is therefore a bit 'lighter.' There are a multitude of papers that have worked to understand the relationship between temperature, turbidity, and density of the incoming waters to lakes and their contributions to the sediment record. With the ice flow then gone afterward, the water column is allowed to mix much more evenly and the flow is not forced beneath the surface waters. Good work!
Thanks again,
Dan