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John_the_Younger

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #100 on: July 09, 2023, 02:53:15 AM »
As goes Greenland, so goes the Arctic?
(Greenland had record mass losses in 2012 and the (current) minimum Arctic sea ice area happened that year.)
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #101 on: July 09, 2023, 08:14:44 AM »
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #102 on: July 09, 2023, 08:37:56 AM »
That is the highest I recall ever seeing it. Is it a record?

HapHazard

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #103 on: July 09, 2023, 10:12:13 AM »
I'm hoping to hike the Arctic Circle Trail in Greenland sometime in the next 5 or so years. I'm starting to think I should speed things up if I want to see any ice...

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sidd

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #104 on: July 09, 2023, 10:16:19 AM »
Re: is it a record

it all melted about a decade ago

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #105 on: July 09, 2023, 11:57:13 AM »
It certainly did - in 2012. The cumulative melt and the SMB (Surface Mass Balance) losses during the melt season were so high that no year since has been anywhere close. An extreme extreme outlier.

DMI have the data, but have not published the daily Melt and SMB data for the years before 2017. They have plans to do so, but no funding. Budget on a shoestring syndrome.

NSIDC Greenland Today publish a dataset of daily melt going back to 1979, but not for SMB, which in the end is the more important metric for the GIS mass balance trend. However they must use a different model from DMI for melt, as the results differ from day to day and overall produce daily melt data somewhat lower than that from DMI.

Here are 2 graphs I made from that data that show how extraordinary 2012 was.

Last EDIT: Despite that extraordinary melt, over the DMI year Sept to Aug precipitation exceeded melt+runoff, so the SMB increased but by much less than average. The trend is for melt to increase but also precipitation, so annual SMB increase is expected to increase further until a tipping point is reached, caused by higher melt and more precipitation falling as rain on snow events. Someone needs to cough up funding so DMI can do more including more published data.
« Last Edit: July 09, 2023, 12:22:45 PM by gerontocrat »
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #106 on: July 09, 2023, 10:16:06 PM »
While ultimately volume changes over time or SMB are more important I was wondering about the extent percentage. Did the extent percentage for one day melt exceed its current level? Was saying it all melted indicating it reached 100% at some point?

kassy

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #107 on: July 09, 2023, 10:25:39 PM »
The peak is nearly double which is about the area which is white in the last picture of this year.
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #108 on: July 10, 2023, 12:41:18 AM »
While ultimately volume changes over time or SMB are more important I was wondering about the extent percentage. Did the extent percentage for one day melt exceed its current level? Was saying it all melted indicating it reached 100% at some point?
The area of Greenland is 2,166,086 km2
The area of the GIS (Wikipedia) is 1,755,637 km2
The area of the GIS (NSIDC) is 1.71 million km2

The maximum daily melt in 2012 per NSIDC's "Greenland Today" was on July 11 at 1,463,750 km2, 85.6% of the GIS area using the NSIDC measurement.

Although 3 days in 2012 were higher than the current values of 2023 daily melt from DMI, the extreme spike in 2012 only lasted about 7 days, while the current 2023 extreme values have lasted 12 days so far.

So maybe 2023 is setting some sort of record for the length of time of sustained extreme melt.

Caveat
: I believe Greenland Today uses a somewhat different algorithm to measure daily melt from that used by DMI. The Greenland Today values of recent years seem to be consistently lower than those of DMI. So maybe the comparison is invalid? Mixing different measurement systems of the same data seems always to bring problems.
« Last Edit: July 10, 2023, 12:56:55 AM by gerontocrat »
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #109 on: July 10, 2023, 06:44:23 AM »
Thanks Gerontocrat for the explanation. Interesting stuff.

oren

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #110 on: July 10, 2023, 04:42:15 PM »
Quote
The extreme melt year of 2012 had two separate intense melt events. The mostunusual melt event occurred on 11–12 July 2012 and was unprecedented during this and the previouscentury, covering ~99% of the ice sheet surface including areas >3000 m at Summit Station (Figure 1a)according to data from multiple satellite sensors [Nghiem et al., 2012]. Melt this extensive had not occurredsince 1889 (+/1 year) according to ice core records [Nghiem et al., 2012; Clausen et al., 1988; Alley andAnandakrishnan, 1995]. Another large melt event occurred on 29 July 2012, where ~79% of the surfaceexperienced some melt according to data from multiple satellite sensors [Nghiem et al., 2012].

https://www.researchgate.net/publication/260335067_Greenland_Ice_Sheet_Melt_from_MODIS_and_Associated_Atmospheric_Variability#pf2

sidd

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #111 on: July 10, 2023, 11:03:08 PM »
There was also an atmospheric river involved in 2012. I haven't the time to find the paper, but i believe i put a link to it somewhere i n this forum.

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #112 on: July 11, 2023, 02:52:48 PM »
Quote
The extreme melt year of 2012 had two separate intense melt events. The mostunusual melt event occurred on 11–12 July 2012 and was unprecedented during this and the previouscentury, covering ~99% of the ice sheet surface including areas >3000 m at Summit Station (Figure 1a)according to data from multiple satellite sensors [Nghiem et al., 2012]. Melt this extensive had not occurredsince 1889 (+/1 year) according to ice core records [Nghiem et al., 2012; Clausen et al., 1988; Alley andAnandakrishnan, 1995]. Another large melt event occurred on 29 July 2012, where ~79% of the surfaceexperienced some melt according to data from multiple satellite sensors [Nghiem et al., 2012].

https://www.researchgate.net/publication/260335067_Greenland_Ice_Sheet_Melt_from_MODIS_and_Associated_Atmospheric_Variability#pf2
The Greenland Today data says that the July 11 2012 melt was 85.6% of the area of the Greenland ice sheet. Different algorithms, different results.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #113 on: July 11, 2023, 03:04:57 PM »
Meanwhile in 2023......

DMI data as at 10th July


Daily melt once again above 65%. It seems to me that once again the concentration of attention on one day records takes attention away from what may be a lower value but sustained over an unusually long period. In 2023 the effect can be seen on the accumulated melt line on the graph.

SMB loss on this day well above average.

It looks like high daily melt and relatively low precipitation will be maintained for the next few days. But by day 7, the Greenland High basically disappears, and melt may return to average or below average levels. The absence of a blocking high may also allow increased precipitation mostly from the South and SouthWest, which being warm may include significant rain on snow reaching to higher altitudes, that could keep SMB losses high.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #114 on: July 12, 2023, 03:21:31 PM »
July 12 - and it continues....
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #115 on: July 12, 2023, 08:21:58 PM »
14 days in a row over 55 % and 4 of the last 5 days over 65%. That is not good.

Alexander555

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #116 on: July 12, 2023, 09:15:13 PM »
How would the accumulated anomaly since sep 1 look like ?

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #117 on: July 12, 2023, 09:37:34 PM »
How would the accumulated anomaly since sep 1 look like ?
The current accumulated melt in 100% days equivalent on July 11 2023 is 14.31. The corresponding data for 2022 is 10.06, and for the 2017-2022 average is 12.00. I cannot give you a figure for the long-term average as the DMI data is not available to me.
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Alexander555

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #118 on: July 12, 2023, 10:04:17 PM »
That positive anomaly on the edge of the west side is probably gone in the last 10 days. That includes the area that's connected with the future "  lake greenland ". How would that area ( where the water meets the ice)  look like today ? Is it like a bay, or like a river ?

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #119 on: July 13, 2023, 12:26:18 PM »
Attached is the Greenland bedrock map, i.e. with the ice sheet removed. The future in n thousand years from now where n is the unknown quantity.

Also attached is the current accumulated SMB anomaly map.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #120 on: July 13, 2023, 12:47:56 PM »
DMI data as at 12th July

Daily melt above 60% for WHOOPS 8 7 days in a row, and above 50% for 16 days in a row.
The effect can be seen on the accumulated melt line on the graph which has left the 2017-2022 average well behind.

This length of time of sustained melt must be in record territory.

SMB loss on this day well above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 552GT accumulated SMB is now 46GT (9%) above the 2017-2022 average of 506GT.

The Greenland High weakens and centres over NE Greenland. Daily melt may remain at higher than average levels. The absence of a blocking high may also allow increased precipitation mostly from the South and SouthWest, which being warm may include significant rain on snow reaching to higher altitudes, that could keep SMB losses high.

When I have time (bad joke?) I will post some gifs on SMB and melt.
« Last Edit: July 13, 2023, 10:12:09 PM by gerontocrat »
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oren

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #121 on: July 13, 2023, 12:57:02 PM »
Quote
Daily melt above 60% for 8 days in a row, and above 50% for 16 days in a row.
Amazing.

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #122 on: July 13, 2023, 09:46:21 PM »
Quote
Daily melt above 60% for 8 days in a row, and above 50% for 16 days in a row.
Amazing.
A day later and I count 7 days above 60% and 16 days above 50%. It is hard for me to count the lines apparently.

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #123 on: July 13, 2023, 10:09:43 PM »
Quote
Daily melt above 60% for 8 days in a row, and above 50% for 16 days in a row.
Amazing.
A day later and I count 7 days above 60% and 16 days above 50%. It is hard for me to count the lines apparently.
Ok, my bad

& here are gifs for Accumulated and Daily SMB since the maximum SMB on 27th June, and daily melt from the same day.

The Accumulated SMB map shows SMB increasing in the West, reflecting that most precipitation is coming from the SouthWest. AS yet all the daily melt has yet to make a big impact on SMB - much melt being absorbed into the ice and compacted snow cover?

click gifs to start, each runs 6 times.
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #124 on: July 13, 2023, 10:46:39 PM »
Quote
Daily melt above 60% for 8 days in a row, and above 50% for 16 days in a row.
Amazing.
A day later and I count 7 days above 60% and 16 days above 50%. It is hard for me to count the lines apparently.
Ok, my bad



I think it was my error I looked at previous day again and came up with the corrected numbers.

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #125 on: July 14, 2023, 05:39:57 PM »
DMI data as at 13th July

Daily melt above 60% for 8 days in a row, and above 50% for 17 days in a row.
The effect can be seen on the accumulated melt line on the graph which has left the 2017-2022 average well behind.

This length of time of sustained melt must be in record territory.

SMB loss on this day well above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 543GT accumulated SMB is now 40GT (8%) above the 2017-2022 average of 503GT.

GFS forecasts that the Greenland High weakens and basically disappears by day 7. Daily melt may be highly variable in the next week or so - both quite low and very high. The absence of a blocking high may also allow increased precipitation mostly from the South and SouthWest, which being warm is forecast to include significant rain on snow reaching to higher altitudes, that could keep SMB losses high.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #126 on: July 15, 2023, 11:00:43 AM »
Data as at 14 July

Images attached (daily melt only 59.97%)
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #127 on: July 16, 2023, 02:07:28 PM »
DMI data as at 15th July

Daily melt was above 60% for 8 days in a row, and is above 50% for 19 days in a row.
The accumulated melt line on the graph has left the 2017-2022 average well behind curretly on course to be a record for the years from 2017.

This length of time of sustained melt must also be in record territory.

SMB loss on this day well above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 529GT accumulated SMB is now 35GT (8%) above the 2017-2022 average of 494GT.

The high melt but also high SMB is in line with most model projections. They project that as the years go by melt will increase but so will SMB as warmer wetter air brings more precipitation. If AGW persists a tipping point will be reached as a warmer Greenland means SMB includes more rain on snow events even in winter, which increases run-off and by reducing albedo allows insolation to increase melt in summer.

GFS forecasts that the Greenland High weakens and moves to the NE and basically disappears by day 7. Daily melt may be highly variable in the next week or so - both quite low and very high with very high melt possible in days 4 to 6 and reduced melt in days 7 to 10. The absence of a blocking high may also looks like allowing increased precipitation mostly from the South and SouthWest, which being warm is forecast to include at least one significant rain on snow in 4 days time in the West reaching to higher altitudes, that could keep SMB losses high.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #128 on: July 17, 2023, 12:56:51 PM »
DMI data as at 16th July

Daily melt was above 60% for 8 days in a row, and is above 50% for 20 days in a row.
The accumulated melt line on the graph has left the 2017-2022 average well behind, and is  currently on course to be a record for the years from 2017.

This length of time of sustained melt at this level must also be in record territory.

SMB loss on this day above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 524GT accumulated SMB is now 34GT (7%) above the 2017-2022 average of 490GT.

The high melt but also high SMB is in line with most model projections. They project that as the years go by melt will increase but so will SMB as warmer wetter air brings more precipitation. If AGW persists a tipping point will be reached as a warmer Greenland means SMB includes more rain on snow events even in winter, which increases run-off and by reducing albedo allows insolation to increase melt in summer.

GFS still forecasts that the Greenland High weakens and moves to the NE and basically disappears before day 7. Daily melt may be highly variable in the next week or so - both quite low and very high with very high melt possible to days 4 to 6 and then reduced melt in days 7 to 10. The absence of a blocking high may also looks like allowing increased precipitation mostly from the South and SouthWest, which being warm is forecast to include at least one significant rain on snow event in the SouthWest reaching to higher altitudes, that could keep SMB losses high.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #129 on: July 18, 2023, 07:52:22 PM »
Images only today. The melt goes on.
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #130 on: July 19, 2023, 02:08:31 PM »
DMI data as at 18th July

Daily melt was above 60% for 8 days in a row, is up above 60% (just) on this day, and is above 50% for 22 days in a row.

The accumulated melt line on the graph has left the 2017-2022 average well behind, and is  currently on course to be a record for the years from 2017.

This length of time of sustained melt at this level must also be in record territory.

SMB loss on this day above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 512GT accumulated SMB is now 32GT (7%) above the 2017-2022 average of 481GT.

The high melt but also high SMB is in line with most model projections. They project that as the years go by melt will increase but so will SMB as warmer wetter air brings more precipitation. If AGW persists a tipping point will be reached as a warmer Greenland means SMB includes more rain on snow events even in winter, which increases run-off and by reducing albedo allows insolation to increase melt in summer.

GFS still forecasts that the Greenland High weakens and moves to the NE and strengthens by day 7 and beyond. Daily melt may be highly variable in the next week or so - both quite low and very high with very high melt possible to days 4 to 6 and then significantly reduced melt after day 4.

The absence of a strong blocking high may also looks like initially allowing increased precipitation mostly from the South and SouthWest, which being warm is forecast to include at least one significant rain on snow event in the SouthWest reaching to higher altitudes, that could keep SMB losses high. By day 7 as the high strengthens, lows are forced westwards south of Greenalnd leaving Greenland mostly dry - and sunny?

Overall it looks more likely that this period of extreme melt will return to more normal levels within the next week
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #131 on: July 20, 2023, 09:31:04 AM »
As at 19th July images only today.
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #132 on: July 20, 2023, 08:31:35 PM »
There are two sources of data for Greenland Surface Melt, DMI and NSIDC's Greenland Today.

This post is to explain why I feel unable to use the data from NSIDC's Greenland Today even though it is a full dataset of daily data going back to 1979 while DMI's daily dataset only goes back to 2017.

Greenland Today issues surface melt data by Km2. DMI issues surface melt data by percentage of the Greenland Ice Sheet melting. In the graphs attached I converted to DMI's Percentage data to Km2 area by using NSIDC's Greenland Ice Sheet measure of 1.71 million km2.

The first graph shows the difference between DMI and Greenland Today of daily melt in 2023 and the 2017-2022 average. The Greenland Today data is significantly less than the DMI data.

The 2nd graph shows the impact on the cumulative melt data. For the 2017-2022 average, by the end of the melting season the Greenland Today data is less than half that of the DMI data. A similar outcome is shown for 2023 data to date.

It is normal to have different results of the same event from different sources using different algorithms. But this difference is extreme. I have checked my calculations, and unless I have had a brain breakdown the analysis is sound.

If anyone has any info on this please post it, as I will be sending emails to DMI and NSIDC asking for their comments.
« Last Edit: July 21, 2023, 11:16:34 AM by gerontocrat »
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #133 on: July 21, 2023, 11:28:16 AM »
DMI data as at 20th July

Daily melt was above 60% for 8 days in a row, below 60% (just) on this day, and is above 50% for 24 days in a row.

The accumulated melt line on the graph has left the 2017-2022 average well behind, and is  currently on course to be a record for the years from 2017.

This length of time of sustained melt at this level must also be in record territory.

SMB loss on this day above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped below the 2022 accumulated SMB.
On this day, at 500GT accumulated SMB is 28GT (6%) above the 2017-2022 average of 472GT.

GFS now forecasts that a moderate Greenland High strengthens a bit. Daily melt may be highly variable in the next week or so - but in general reducing somewhat over the forecast period.

The absence of a strong blocking high may also looks like allowing some precipitation mostly from the South and SouthWest, which being warm is forecast to include occasioanl rain on snow events in the SouthWest reaching to higher altitudes, that could keep SMB losses above average. As the high strengthens, Greenland gets drier - and sunnier?

Overall it looks more likely that this period of extreme melt will return to more normal levels within the next week
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #134 on: July 22, 2023, 11:10:34 AM »
Images only today...
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #135 on: July 23, 2023, 12:06:31 AM »
NASA / JPL have issued Greenland Mass Balance data for another month to mid-May 2023.

A small gain in Greenland Mass in the month due to SMB gains being greater than GIS mass loss from glaciers calving and melting by ocean waters.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #136 on: July 23, 2023, 10:27:59 AM »
DMI data as at 22nd July

Daily melt was above 60% for 8 days in a row, below 60% (just) on this day, and is above 50% for 26 days in a row.

The accumulated melt line on the graph has left the 2017-2022 average well behind, and is  currently on course to be a record for the years from 2017.

This extremely lengthy sustained melt at this level must also be in record territory.

SMB loss on this day above average. However, accumulated SMB gain this year is still well above the longterm average, though it has dipped well below the 2022 accumulated SMB.
On this day, at 489GT accumulated SMB is 26GT (6%) above the 2017-2022 average of 463GT.

GFS now forecasts that the weak Greenland High strengthens somewhat over the next week or so. Daily melt looks to generally reduce somewhat over the forecast period, with the high increasingly blocking precipitation especially after days 1 to 3. Perhaps a drier and sunnier Greenland in prospect?

Overall it looks more likely that this period of extreme melt will return to more normal levels but maybe at or above average within the next week while daily SMB losses stay above average
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #137 on: July 24, 2023, 03:54:01 PM »
DMI data as at 23rd July

Only images today, but the melt goes on
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #138 on: July 24, 2023, 05:53:58 PM »
Updated graphs comparing Greenland Today melt data with DMI melt data are attached (1st & 2nd images).

The Greenland Today melt data is concistently less than the DMI data. Nevertheless the Greenland Today graphs (3rd & 4th images) show that without the very slow 2023 melt from April to late June 2023 melt to date might have been close to the 2012 extreme record.
« Last Edit: July 24, 2023, 06:03:32 PM by gerontocrat »
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #139 on: July 25, 2023, 11:16:09 AM »
DMI data as at 22nd July

Daily melt was above 60% for 8 days in a row, below 60% (just) on this day, and is above 50% for 28 days in a row.

The accumulated melt line on the graph has left the 2017-2022 average well behind, and is  currently on course to be a record for the years from 2017.

This extremely lengthy sustained melt at this level must also be in record territory.

SMB loss on this day above average. However, accumulated SMB gain this year is still somewhat above the longterm average, though it has dipped well below the 2022 accumulated SMB. On this day, at 476GT accumulated SMB is 21GT (5%) above the 2017-2022 average of 455GT.

GFS now forecasts that the Greenland High persists but variable in strength and location during the next week or so. Daily melt looks to generally reduce somewhat over the forecast period, with the high keeping Greenland mostly dry and sunny.

Overall it looks more likely that this period of extreme melt will return to more normal levels but maybe at or above average within the next week while daily SMB losses may stay above average
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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #140 on: July 26, 2023, 05:50:44 AM »
How often do they do full gravity scans. How much of this is modeled? How often is there altimetry data?

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #141 on: July 26, 2023, 08:28:36 PM »
How often do they do full gravity scans. How much of this is modeled? How often is there altimetry data?
Je ne sais pas. But DMI funding is totally inadequate for both the scale and importance of the task they face.

Meanwhile,

DMI info as at 25th July


Daily melt at 47% is below 50% for the first time since June 26th.

Daily SMB loss is well above average again, with accumulated SMB gain at 470 GT now 19GT above the 2017-2022 average of 451GT.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #142 on: July 27, 2023, 10:49:35 AM »
DMI info as at 26th July

Daily melt at 44% is still well above avereage.

Daily SMB loss is well above average again, with accumulated SMB gain at 463 GT now 15GT (3%) above the 2017-2022 average of 448GT.

The GFS forecast has the Greenalnd High strengthening over the next week to 10 days, with Greenalnd becoming cooler and staying mostly dry. SMB daily losses may stay well above average while daily melt initially declines and perhaps increases a bit after day 7.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #143 on: July 28, 2023, 09:02:17 AM »
DMI info as at 27th July

Daily melt at 42% is still well above avereage.

Daily SMB loss is well above average again, with accumulated SMB gain at 457 GT now 13GT (3%) above the 2017-2022 average of 444GT.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #144 on: July 30, 2023, 08:08:21 PM »
DMI info as at 29th July

Daily melt at 41% is still well above avereage.

Daily SMB loss is just below average on this day, with accumulated SMB gain at 448 GT now 13GT (3%) above the 2017-2022 average of 435GT.

The Greenland High still looks like it will strengthen though temperatures suggest daily melt may reduce to more average levels and precipitation looks like remaining subdued.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #145 on: July 31, 2023, 10:51:30 AM »
DMI info as at 30th July

Daily melt at 38% is lower but still well above avereage.

Daily SMB loss is just below average on this day, with accumulated SMB gain at 445 GT now 16GT (4%) above the 2017-2022 average of 429GT.

The Greenland High still looks like it will strengthen though temperatures suggest daily melt may stay reduced to more average levels and precipitation looks like remaining lowish.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #146 on: August 01, 2023, 02:26:11 PM »
DMI data as at 31 July

Daily melt at 36% is lower but still well above avereage.

Daily SMB loss of 2.0 GT is well below the average on this day of 5.8GT, with accumulated SMB gain at 443 GT now 20 GT (5%) above the 2017-2022 average of 423GT.

The Greenland High still looks like it will strengthen though temperatures suggest daily melt may  reduce some more to more average levels, though it may pick up after a week. Precipitation looks like average to lowish.
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Niall Dollard

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #147 on: August 02, 2023, 02:21:06 PM »
Gif showing the recent snow accumulation over northern Greenland. Needs a click

gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #148 on: August 03, 2023, 03:56:00 PM »
DMI data as at 2nd August

Daily melt at 33% is lower but still above avereage for the time of year

Daily SMB loss of 0.5 GT is well below the 2017-2022 average on this day of 4.9 GT, with accumulated SMB gain at 442 GT now 29 GT (7%) above the 2017-2022 average of 413GT.

The Greenland High still looks like it stay though temperatures suggest daily melt may reduce some more to more average levels, though it may pick up after a week. Precipitation looks like average to lowish to maybe higher with orecipitation from the Wast in days 7 to 10.
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gerontocrat

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Re: Greenland 2022-23 SMB, melting and GRACE mass
« Reply #149 on: August 04, 2023, 04:53:48 PM »
Only time for the images today - i.e. no blurb
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