Monday, July 4, 2016
Sea ice affected by a lot of snow, THE END story
~Not to forget tidal action
NASA EOSDIS Barrow Strait rapid sea ice disintegration (June 29-July 3, 2016), notice the greyish looking capture pre and post breaking sea ice. That is the colour of thin sea ice, finally revealed by most of the snow melted or sublimated. It broke likely on about June 30 July 1. What is so special about that date? It is a few days before the new moon, a very potent time for stronger tidal driven sea current. This GIF animation demonstrates 2 major players, greater than normal snowfall created this ice earlier, and now despite being thinner, the snow preserved it to last a bit later. But Barrow Strait ice was terribly vulnerable, and a mere extra tidal current took care of it quite well with ease. The larger image provided by NASA allows us to hunt for similar looking ice on EOSDIS whenever available by cloud clearings, the "grey ice of doom" can be seen pretty much everywhere. None so clearer in the Canadian High Arctic at this time.WD July 4th, 2016
Thursday, June 30, 2016
Effects of greater snowfall are lasting in some regions.
Lets focus on the Eastern NW passage where there was more snowfall:
What happens with more snowfall has long lasting implications for sea ice. First we have greater cooling of top of sea when it falls in autumn, the snow floats doesn't melt, acts like a proxy ice cover, and accelerates the grey ice sea ice genesis. This creates more rapid onset of fast ice. Now, lets fast forward to its effect to this early summer, many months later from October-November just past. EOSDIS
pictures of June 29, 2015 and 16 are marked upper left corner. But the great deal of snow during winter of 2015-16 affected sea ice morphology, and therefore its current cooler summer weather.
Look carefully where the snow remains in 2016 and you will inherently find more sea ice, because snow help made it, and also created a buffer slowing its melt. But the larger implication is the local early summer weather snow and greater sea ice extent created, cooler, and also strangely but so, thinner sea ice. Winds of 2015 in the same area as on this GIF animation were dry, there was less snowfall, which happened more on the western European side of the Arctic which happens to have far less sea ice extent on its coastal shores. 2015 sea ice eventually became thicker when formed, but open water Polynyas in 2015 were much larger because there was a great deal of wind from the North (not unusual) keeping top of sea water from forming ice . In late spring 2015, the land warmed quicker, local weather was equally warmer and residual July snow footprint far lesser. WD June 30,2016
Tuesday, June 28, 2016
Near North Pole current Ice condition, between a rock frozen ice and a cloudy cooler place.
June 28,2016, near North Pole ice conditions show "pancakes" typical of fluid sea ice, terribly broken up. Very little sign of old ice. But there was extensive compression during the Spring just past, this can be its undoing, a strong consolidated pack cools the air more, good spawning ground for Highs.
June 30 2013, same location, offered a glimpse on the damaged caused in 2012 melt. However,
the degree of open water caused by much thinner sea ice triggered what many contrarians deemed incorrectly "a cooling" especially at minima mid September 2013, because substantially less ice apparently melted, not so, it was an extent calculation 15% problem. This open water caused extensive Lows to penetrate and remain over the ice Pack throughout the summer. Current situation in 2016 seems between a strong consolidated pack and a loose Cyclone-genesis driven summer. The danger for 2016 sea ice is for less clouds to form at this time, un-likewise 2013, this is very possible. WD June 28 2016
June 30 2013, same location, offered a glimpse on the damaged caused in 2012 melt. However,
the degree of open water caused by much thinner sea ice triggered what many contrarians deemed incorrectly "a cooling" especially at minima mid September 2013, because substantially less ice apparently melted, not so, it was an extent calculation 15% problem. This open water caused extensive Lows to penetrate and remain over the ice Pack throughout the summer. Current situation in 2016 seems between a strong consolidated pack and a loose Cyclone-genesis driven summer. The danger for 2016 sea ice is for less clouds to form at this time, un-likewise 2013, this is very possible. WD June 28 2016
Monday, June 27, 2016
Despite contrarian winds, Beaufort Gyre current is still very strong
NASA EOSDIS 11 days of June 2016 selected at about 2 or 3 day intervals. You can see cyclones moving through along with contrarian winds, there were quite a few small cyclones hanging about during the same period. But nothing , literally nothing stopped the surface current moving the ice clockwise. This is explainable by 3 of many sea ice displacement vectors. The coriolis effect, note its not a force, sea ice momentum movement (a seldom discussed displacement vector) and finally the Beaufort Gyre itself, reinvigorated by months of clockwise circulation of mixed aged pack ice. This implies any lull in winds will cause compaction to occur nevertheless. wd June 27 2016.
Tuesday, June 7, 2016
The models may be calculating the sea ice surface to air interface temperatures incorrectly
~ Some surface buoys corroborate the prime horizon refraction rule
Having dealt before with doubtful calculations output by NOAA NCAR/NCEP with respect to top sea ice temperature, it seems suspicion confirmed by remote weather stations placed on sea ice. The ice core temperature minimum of 2015f (82 N 147 W) in particular on June 5 was really cold with lowest sun position, but as usual, solar radiation whacked out any precision with top thermistors most times, leaving us with only its average surface temperature to contemplate. It was -4.8 C for that day. At the same location NCAR/NCEP calculated -3. Now consider that an actual measurement can be done from space, the skin temperature or ice surface, it should be quite precise. NCAR/NCEP result was between -1 and 0 C. However, this is a violation of sea ice refraction prime rule, top of sea ice was never observed warmer than surface air. To cap this off, 2015f reported 12:00 UTC surface temperature at -7.39 C, now we turn to nearby sea ice surface weather stations at 12:00 UTC 80 N 110 W read -1, 76 N 160 W read -2. Welcome to the world of metric confusion, when temperatures seem really irregular. Another surface Auto station on Prince Patrick Island reported a more probable -7 (76 N 120 W).
To make sense of all this, one must weed out possible errors, to play it safe, only 2015f surface measurements seem accurate along with surface temperature from land based auto station. Why so? Because thermistor 2, likely in ice, recorded -6.7 C at 12 UTC, with a low sun solar radiation corruption. Later, the morning less bombarded with photons thermistor shoots up 5 C in 8 hours with higher sun. 2015f reported surface temp -2.9 C at 20:00 UTC while same colder morning thermistor reported +0.17 C, one would expect similar rise in temperature between surface and top of sea ice, but sea ice gained more degrees than surface measurement, again highly unlikely since sea ice and snow have very strong albedo, unless of course there is water on the said thermistor surrounded by sea ice.
No wonder Arctic models have trouble being precise, there is very little accurate observations to compare their output with.
June 5 1200 UTC CMC surface analysis.
Having dealt before with doubtful calculations output by NOAA NCAR/NCEP with respect to top sea ice temperature, it seems suspicion confirmed by remote weather stations placed on sea ice. The ice core temperature minimum of 2015f (82 N 147 W) in particular on June 5 was really cold with lowest sun position, but as usual, solar radiation whacked out any precision with top thermistors most times, leaving us with only its average surface temperature to contemplate. It was -4.8 C for that day. At the same location NCAR/NCEP calculated -3. Now consider that an actual measurement can be done from space, the skin temperature or ice surface, it should be quite precise. NCAR/NCEP result was between -1 and 0 C. However, this is a violation of sea ice refraction prime rule, top of sea ice was never observed warmer than surface air. To cap this off, 2015f reported 12:00 UTC surface temperature at -7.39 C, now we turn to nearby sea ice surface weather stations at 12:00 UTC 80 N 110 W read -1, 76 N 160 W read -2. Welcome to the world of metric confusion, when temperatures seem really irregular. Another surface Auto station on Prince Patrick Island reported a more probable -7 (76 N 120 W).
To make sense of all this, one must weed out possible errors, to play it safe, only 2015f surface measurements seem accurate along with surface temperature from land based auto station. Why so? Because thermistor 2, likely in ice, recorded -6.7 C at 12 UTC, with a low sun solar radiation corruption. Later, the morning less bombarded with photons thermistor shoots up 5 C in 8 hours with higher sun. 2015f reported surface temp -2.9 C at 20:00 UTC while same colder morning thermistor reported +0.17 C, one would expect similar rise in temperature between surface and top of sea ice, but sea ice gained more degrees than surface measurement, again highly unlikely since sea ice and snow have very strong albedo, unless of course there is water on the said thermistor surrounded by sea ice.
No wonder Arctic models have trouble being precise, there is very little accurate observations to compare their output with.
June 5 1200 UTC CMC surface analysis.
Sunday, June 5, 2016
Sometimes Top and bottom Melting looks like this
At onset of top melting the horizon appears slightly jagged, water is setting on top of sea ice. The ice core is very warmed yet colder than the air, the horizon is slightly above astronomical horizon, but the new surface water brings it down. wd June 5 ,2016
Sunday, May 29, 2016
2nd remarkable retreat front
~ Early Great Blue gaining on sea ice not only for Beaufort sea
Post news:
Post news:
June 14 EOSDIS, the 2nd melt front appears to have filled with loose pack sea ice spread out because temperatures have warmed much further. Consolidation lost, sometimes extent values may give a false idea about current sea ice action. Make no mistakes in judgement, this is the greatest melt in history. It comes with scattering of loose ice, from that point, greater clouds are possible, although not lasting because air temperatures are too warm. WD June 14,2016
Friday, May 20, 2016
No sea ice horizon upwards rebound observed close to Midnight sun
~Optical Thermal observation method further explained, proving Ti<=Ta
~Likely 24 hour bottom melt earliest captured....
Preceding article questioning NCAR calculations can be seen here. The sea ice Horizon would
drop below Astronomical Horizon (AH) if top of sea ice was warmer than surface air. In many years of observations it was never observed doing that, the much lower sea water horizon observations with colder than sst air were never repeated with ice. Instead spring sea ice horizons maintain AH until evening or until under sea ice melting is 24 hours a day. This likely happened yesterday, South Cornwallis Island looking at westward MW Passage.
On a given Arctic spring day, the horizon drops to AH when the air temperature Ta is equal to top of sea ice temperature Ti. When reaching AH, it is highly likely that the bottom of sea ice melts,
but during spring the AH horizon lasts a few minutes when it first shows, in March or early April, so accretion keeps on making net gains. AH horizons gradually become longer, but when AH is maintained more than 12 hours, the bottom of sea ice melts more than forms, net bottom melting occurs. This has happened yesterday, when AH was observed 1 hour before the midnight sun. For the first time I have observed this in May, this makes Spring 2016 fast ice the weakest heat resisting sea ice observed since 2010 when spring observations have started.
~Likely 24 hour bottom melt earliest captured....
Preceding article questioning NCAR calculations can be seen here. The sea ice Horizon would
drop below Astronomical Horizon (AH) if top of sea ice was warmer than surface air. In many years of observations it was never observed doing that, the much lower sea water horizon observations with colder than sst air were never repeated with ice. Instead spring sea ice horizons maintain AH until evening or until under sea ice melting is 24 hours a day. This likely happened yesterday, South Cornwallis Island looking at westward MW Passage.
On a given Arctic spring day, the horizon drops to AH when the air temperature Ta is equal to top of sea ice temperature Ti. When reaching AH, it is highly likely that the bottom of sea ice melts,
but during spring the AH horizon lasts a few minutes when it first shows, in March or early April, so accretion keeps on making net gains. AH horizons gradually become longer, but when AH is maintained more than 12 hours, the bottom of sea ice melts more than forms, net bottom melting occurs. This has happened yesterday, when AH was observed 1 hour before the midnight sun. For the first time I have observed this in May, this makes Spring 2016 fast ice the weakest heat resisting sea ice observed since 2010 when spring observations have started.
Thursday, May 19, 2016
Optically unlikely not possible remote sensing/model? measurements/calculations
85 to 90 N NOAA Reanalysis. May 16, 2016. Use the mouse pointer to compare surface and top of sea ice temperatures.
There are several reasons why surface sea ice temperature can't be warmer than surface air. #1 It is optically not observable, if there is a steep adiabatic profile from ground/ice temperature to Surface air 2 meters above, it would give an optical illusion, similar to hot road mirages. We have here on this example given many locations with a 2 degree C temperature difference between skin to surface air. This would give a lapse rate 100 times more than the normal 10 C/Km. #2 Thermally improbable. Top of sea ice temperature influences the surface air temperature, if the air is colder than top of sea ice, this is a very unstable thermal structure, ice would cool rapidly by convection upwards of the air touching it. While air warmer than sea ice invokes a normal stable thermal structure. Because ice/snow surface is white, especially since thermal conduction from lower in the column sea ice is much greater than air to top of ice, air conduction affects top of sea ice less than colder sea ice column core minima, very necessarily at this time of late spring. #3 clouds. Likely covering 85N to the Pole here, clouds offer a more neutral thermal flux balance, whereas there is a steady equal heat flux up and down at the surface to air interface. The net result is more of an isotherm, but still slightly favoring the stable thermal structure, which is colder top of sea ice than surface air. WD May 19, 2016
Subscribe to:
Posts (Atom)