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Anne

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Re: What the Buoys are telling
« Reply #50 on: July 02, 2013, 10:14:57 PM »
Thanks, Jim, that was helpful. Occasionally vertical lines appear like aerials. They must be some sort of telemetry transmitters.

I give in. How did you find it?

Peter Ellis

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Re: What the Buoys are telling
« Reply #51 on: July 02, 2013, 10:22:35 PM »
Thanks, Jim, that was helpful. Occasionally vertical lines appear like aerials. They must be some sort of telemetry transmitters.

I give in. How did you find it?
Take the URL for the Buoy 8 video and change the 8 to a 7....    ::)

Anne

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Re: What the Buoys are telling
« Reply #52 on: July 02, 2013, 10:26:53 PM »
 Thanks, Peter. Obvious! :-[
« Last Edit: July 02, 2013, 11:33:43 PM by Anne »

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Re: What the Buoys are telling
« Reply #53 on: July 03, 2013, 02:24:47 PM »
O Buoy 7 is above 0C, and the runoff is significant, the clouds seem to be clearing.

On July 1, the ponds were refreezing....ice on the edges, not so today.

First image, 1 July.

Second image, 3 July.

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Re: What the Buoys are telling
« Reply #54 on: July 05, 2013, 10:48:27 AM »
A not entirely off topic diversion on to a learned discussion about what the buoys are not telling Steve Goddard and his loyal band of followers over at "Real Science".

Was there really "New Ice At The North Pole" on July 2nd 2013?

Some early reviews include "Thanks for the laugh" and "most amusing"!
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Re: What the Buoys are telling
« Reply #55 on: July 06, 2013, 01:40:00 PM »
Occasionally vertical lines appear like aerials. They must be some sort of telemetry transmitters.

There's pictures of a recent IMB installation on the 2013A page.



Unfortunately, for my purposes at least, they're accompanied by the information that:

Quote
Thermistors 16-30 not functioning as of 1/24/2013 - Reason: Fox chewed through cables.
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Re: What the Buoys are telling
« Reply #56 on: July 06, 2013, 04:57:45 PM »
In view are the vertical pipes through which the thermister lines are placed and the snow height sensor.

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Re: What the Buoys are telling
« Reply #57 on: July 08, 2013, 10:06:38 AM »
http://obuoy.datatransport.org/monitor#buoy8/webcam

Are these melt ponds or is this open water?

Jim Hunt

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Re: What the Buoys are telling
« Reply #58 on: July 08, 2013, 10:42:33 AM »
Are these melt ponds or is this open water?

Looks like melt ponds to me. However air temperature is now +4, and water temperature has risen above -1.3, so open water seems to be on its way.
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Richard Rathbone

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Re: What the Buoys are telling
« Reply #59 on: July 08, 2013, 01:00:57 PM »
The shape of some of those profiles says melt pond to me. Air shouldn't get a near surface peak, and ice shouldn't be solid at those temperatures.

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Re: What the Buoys are telling
« Reply #60 on: July 08, 2013, 03:00:05 PM »
Ice shouldn't be solid at those temperatures.

Quite so. It also seems the water under OBuoy 7 jumped above -1.2, literally overnight (UTC). Significant surface and bottom melt over there now:
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Re: What the Buoys are telling
« Reply #61 on: July 08, 2013, 06:42:46 PM »
Quite so. It also seems jumped above -1.2, literally overnight (UTC). Significant surface and bottom melt over there now:

Just by itself, that translates into about a CM/day. That should double above -1, and hit about 5CM/day when it hits zero.
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Re: What the Buoys are telling
« Reply #62 on: July 10, 2013, 02:23:40 PM »
Finally, a glimpse through the clouds of the area where the Beaufort buoys are located, courtesy of Worldview bands 7/2/1.

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Re: What the Buoys are telling
« Reply #64 on: July 12, 2013, 10:09:21 AM »
In Web Cam #2 you can see the ice drifting by in the background

Perhaps an easier option is to watch the ice drifting by in the videos? and
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Re: What the Buoys are telling
« Reply #65 on: July 12, 2013, 11:06:46 AM »
Have a ice day!

Bruce Steele

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Re: What the Buoys are telling
« Reply #66 on: July 12, 2013, 04:20:07 PM »
http://www.whoi.edu/itp/images/itp57dat3.jpg
Buoy 57 is fairly close to the north pole and shows significant surface water heating within the last week. The hole at the pole looks more likely than not.

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Re: What the Buoys are telling
« Reply #67 on: July 13, 2013, 08:33:20 AM »
After a couple of weeks of Buoy 8 flopping around after falling through a crack it now looks like Buoy 7 is going the same way:
http://obuoy.datatransport.org/monitor#buoy7/webcam

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Re: What the Buoys are telling
« Reply #68 on: July 13, 2013, 08:40:43 AM »
After a couple of weeks of Buoy 8 flopping around after falling through a crack it now looks like Buoy 7 is going the same way:
http://obuoy.datatransport.org/monitor#buoy7/webcam

<Laughter> That is entirely TOO Ironic, and Funny as hell...
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Re: What the Buoys are telling
« Reply #69 on: July 13, 2013, 01:54:39 PM »
Now it is getting interesting. All buoys report thinning except the most central buoy 2G. The two Beaufort buoys show equal thinning of 1-2cm/day, with a later start of buoy 2H. Both enjoyed a good amount of clear sky recently forecasted to continue. 3B targeting Fram Strait thins a bit less. 6 IMB buoys are still in the race and 3 of them have cams.


Jim Hunt

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Re: What the Buoys are telling
« Reply #70 on: July 13, 2013, 02:57:45 PM »
6 IMB buoys are still in the race and 3 of them have cams.

Although it's not doing itself justice in your charts, I think 2012J is still "in the race". Some of it's sensors have failed, and it has no camera, but the thermistors show the whole floe is now above -2°C:

BTW - I think 4 out of your 6 have cameras?
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Re: What the Buoys are telling
« Reply #71 on: July 13, 2013, 02:59:57 PM »
ITP57 is not showing up to -0.8C, Salinity has dropped now to 31.9PSU.  Wow.

I looked through every ITP deployed in the area since 2004.

Not one even shows the water warming any time during the melt season.


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Re: What the Buoys are telling
« Reply #72 on: July 14, 2013, 03:00:19 AM »
thanks for the link to the videos Jim. It looks like June 11 was the start of ice floe bumper cars at the Pole, as seen on Cam #1, which was a few days after open water became visible (coinciding with the cyclone activity). It looks like there was some movement before, in May on cam #2, but not open water.

wouldn't it be useful to have an Arctic rover...you know like the Mars rover...

Anne

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Re: What the Buoys are telling
« Reply #73 on: July 14, 2013, 09:50:31 AM »
wouldn't it be useful to have an Arctic rover...you know like the Mars rover...

More of these?

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Re: What the Buoys are telling
« Reply #74 on: July 14, 2013, 12:47:20 PM »
Anne,

I think the surface at the pole incl. open leads, is far more uneven than the Greenland Ice Sheet, and the vehicle will run into problems all over the place.
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Anne

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Re: What the Buoys are telling
« Reply #75 on: July 14, 2013, 02:53:06 PM »
I wasn't being entirely serious! What is needed is a rover with hovercraft capabilities. I see they use hovercraft in the Arctic, but they need fairly level surfaces, whether wet or frozen.

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Re: What the Buoys are telling
« Reply #76 on: July 15, 2013, 12:26:22 AM »
Wow, there is some significant melt going on at the moment.  I know this year is still far behind 2012 but I will be interested to see how the bottom melt continues to affect the center.  I have heard some talk of the 'pole hole' being possible this year, but I just don't know. That said I recently read an article talking about deep sea warming and how enormous amounts of energy is being absorbed by the sun (seems sound to me).  Anyways, this current webcam image from the pole is interesting:

pls!

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Re: What the Buoys are telling
« Reply #77 on: July 15, 2013, 02:19:38 AM »
I wasn't being entirely serious! What is needed is a rover with hovercraft capabilities. I see they use hovercraft in the Arctic, but they need fairly level surfaces, whether wet or frozen.

Could do with one of these, with the typical UAV remote sensing equipment attached!

I recently joined the twitter thing, where I post more analysis, pics and animations: @Icy_Samuel

Bob Wallace

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Re: What the Buoys are telling
« Reply #78 on: July 15, 2013, 06:47:46 AM »
Faster than a hungry polar bear?

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Re: What the Buoys are telling
« Reply #79 on: July 15, 2013, 08:07:16 AM »
hmm... maybe something like a mini sub... but with a few legs or flippers....


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Re: What the Buoys are telling
« Reply #80 on: July 15, 2013, 09:54:07 AM »
Needs claws in order to hang on when the wind comes up....

Anne

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Re: What the Buoys are telling
« Reply #81 on: July 16, 2013, 09:03:35 AM »
#8 is back to upright again this morning.

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Re: What the Buoys are telling
« Reply #82 on: July 16, 2013, 10:07:00 AM »
#8 is back to upright again this morning.

And the snow/ice looks pretty soft/rotten too.
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Jim Hunt

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Re: What the Buoys are telling
« Reply #83 on: July 16, 2013, 10:15:38 AM »
#8 is back to upright again this morning.

Indeed it is Anne. A pity it hasn't also auto-rotated to show us all the instrumentation again, because the thermistor temperature profile is looking interesting. I've dropped the May 15th readings, because we're now well into positive territory!
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Re: What the Buoys are telling
« Reply #84 on: July 17, 2013, 04:23:49 AM »
When is a melt pond a melt creek, melt river, or melt lake?
Obuoy #8, webcam capture just a moment ago.
It looks at the far right that water is flowing down a slight difference in elevation. 

A melt cataract, for the denialists who are so blind because they will not see.

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Re: What the Buoys are telling
« Reply #85 on: July 17, 2013, 11:59:25 AM »
Let's not forget OBuoy 7, which is now tilting at an ever more precarious angle. According to IMB 2012L the floe underneath it is melting at the rate of several centimetres a day, and the water underneath the ice just ratcheted up in temperature another tenth of a degree.
« Last Edit: July 17, 2013, 12:23:20 PM by Jim Hunt »
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Re: What the Buoys are telling
« Reply #86 on: July 17, 2013, 02:03:43 PM »
Let's not forget OBuoy 7, which is now tilting at an ever more precarious angle. According to IMB 2012L the floe underneath it is melting at the rate of several centimetres a day, and the water underneath the ice just ratcheted up in temperature another tenth of a degree.

Thanks Jim I find these graphs really interesting, just a quick question, what is the spacing on the thermistor chain?

Jim Hunt

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Re: What the Buoys are telling
« Reply #87 on: July 17, 2013, 02:18:06 PM »
My pleasure Phil. The thermistors are nominally 10cm apart. A bit more information on interpretation is available over on the "Bottom melt in Central Arctic?" thread.
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Anne

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Re: What the Buoys are telling
« Reply #88 on: July 18, 2013, 08:17:24 AM »
The movies for the O-Buoys have been updated and show fascinating development of melt ponds on what was multi-year ice when they were installed last year. (Open water is in the background of the September - October frames.) Solar/lunar and GPS details are shown graphically top left and right of the screen. You need to view full screen.
O-Buoy 8
O-Buoy 7

ghoti

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Re: What the Buoys are telling
« Reply #89 on: July 18, 2013, 04:16:37 PM »
I'm really pleased they added the movie tab to their display page. The diurnal filling and draining of the melt pond and streams is striking.

Jim Hunt

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Re: What the Buoys are telling
« Reply #90 on: July 19, 2013, 03:20:25 PM »
The CAB is melting too now. At the moment NPEO webcam 2 may look "wetter" than webcam 1:



but IMB 2013B reports that 3 cm has melted away in the last 24 hours or so, and the temperature underneath is increasing:
« Last Edit: July 19, 2013, 03:52:54 PM by Jim Hunt »
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Re: What the Buoys are telling
« Reply #91 on: July 20, 2013, 01:53:35 AM »
OBuoy 8 must be psychic. It has now auto-rotated to reveal at least one of the other buoys, plus a glimpse at the thickness of some ice in the vicinity.
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Re: What the Buoys are telling
« Reply #92 on: July 20, 2013, 02:09:43 AM »
IMB 2013B reports that 3 cm has melted away in the last 24 hours or so, and the temperature underneath is increasing:

What do the thermistor data from last years' buoys look like for the second half of July?  We know the surface melt is way behind last year, can you tell us anything about the bottom melt?

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Re: What the Buoys are telling
« Reply #93 on: July 20, 2013, 02:21:02 AM »
OBuoy 8 must be psychic. It has now auto-rotated to reveal at least one of the other buoys, plus a glimpse at the thickness of some ice in the vicinity.

I find this image intriguing, both from the standpoint of implied thickness, and from the small size of the flows.  It also suggests more open water in the form of small leads.  I *think this buoy is in the lower left corner of r05c03 on rapid fire. That area shows up as 97+concentration on Bremen.  I'd put it  below 95,maybe below 90.
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ghoti

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Re: What the Buoys are telling
« Reply #94 on: July 20, 2013, 03:07:40 AM »
Oops! The buoy has been tipped again and is not showing much now. The large movements resulting in the slab the buoy is on getting lifted and dropped is instructive. Lots of little pieces of ice getting stirred around.

Jim Hunt

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Re: What the Buoys are telling
« Reply #95 on: July 20, 2013, 03:20:28 AM »
What do the thermistor data from last years' buoys look like for the second half of July?  We know the surface melt is way behind last year, can you tell us anything about the bottom melt?

I haven't been able to track down a set of thermistors that survived through the summer of 2012. Here's 2010E, which lasted until the end of July 2011 in the Beaufort, before half the thermistors stopped reporting. The colocated ITP gave up the ghost in April.

By the middle of July surface melt was around 50 cm, with 22 cm of bottom melt. The bottom sounder failed on July 26th, after a further 10 cm of bottom melt.
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Re: What the Buoys are telling
« Reply #96 on: July 20, 2013, 03:24:36 AM »
the B&W rods at cam 2 are moving in opposing directions.

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Re: What the Buoys are telling
« Reply #97 on: July 20, 2013, 09:37:17 AM »
It's been too long, time for another stupid question.  ;)

Jim, please give me a quick rundown on how to interpret those ITP graphs you post.
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Re: What the Buoys are telling
« Reply #98 on: July 20, 2013, 11:44:51 AM »
Good morning Neven,

Actually they are IMB graphs! Here's the practical background on an Ice Mass Balance buoy installation, and here's a picture:



Here's a bit of theoretical background from a previous post.

My graphs show the temperature readings from the string of thermistors, taken at two week intervals, plus the most recent set of readings occasionally. The X axis is just the thermistor number, and the thermistors are 10 cm apart.  Number 1 is in the air above the floe.  The last one is in the water below the floe. Hence the left side of the graph shows air temperature, the right hand side shows water temperature, whilst the readings in between could also be from snow, melt water or ice.

Arctic.io's graphs show the top and bottom melt (when all the sensors are working!), whereas mine reveal what's happening inside the floe. Does that make any sense yet?
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Re: What the Buoys are telling
« Reply #99 on: July 20, 2013, 02:49:06 PM »
IMB 2013B reports that 3 cm has melted away in the last 24 hours or so, and the temperature underneath is increasing:

What do the thermistor data from last years' buoys look like for the second half of July?  We know the surface melt is way behind last year, can you tell us anything about the bottom melt?

2012L is the only buoy located really close to that position in the Beaufort and thus it is the only valid comparison. As of 07/20/2013 we have

Current Buoy Data (07/20/2013):

Pos: 74.69 N, 145.80 W

Air Temp: 0.85 C
Air Pres: 1017.48 mb




--------------------------------------------------------------------------------

Current Ice Observations (07/20/2013)

Snow depth : 0 cm (melted 06/18/2013)
Ice thickness : 266 cm

Since Deployment (08/27/2012)

Snow depth at melt onset: 15 cm
Snow melt: 15 cm (Began 06/09/2013)
Ice surface melt: 48 cm (Began 06/18/2013)

Ice bottom melt : 26 cm (Began 06/14/2013)
Ice bottom growth : 12 cm (Began 02/01/2013)

....

How exactly is 48cm of surface melt 'way behind', I ask?