Greenland - What Do We Know, What Is The Long Term Future And Is There Any Evidence Of A Melt Out?

[tablet]

a study published on 25th January 2018 on Nature.com

https://www.nature.com/articles/s41598-018-19992-w

[tablet]

[Devonian]

55 minutes ago, tablet said:

Welcome 'tablet' - you've clearly got a lot to say.

That first graphic is a misleading photoshop, the data line is a 'per year' number (it starts at 0) not a continuum, the plot is for multiple yrs - each year starts at 0.

But, the running accumulated surface mass needs to be positive because??? if it were not positive but zero per year what would happen to the ice sheet?

 

[tablet]

So Mr Devonian ,,, yes all graphs start at zero ,, but all the ice gained from last season hasn't disappeared has it ? it's still there , that is what I was trying to demonstrate , and as you can see from the other graphic's ,,nothing is melting at the moment , and there I was thinking I would bring a little happy news to the people that seem very concerned about Greenland , or do you like making people think all the ice is melting ?

let me put a question directly to you , did last season's ice gain disappear ?

[Gray-Wolf]

I'd be taking a look at albedo for Greenland to find out if last year 'snow' melted?

We have seen the albedo of greenland falling as the dirt trapped in last winters snow gets deposited as the entombing snow melts.

Last Season saw some heavy snow over the east of Greenland from the lows that passed by on their way to warming Svalbard. If we see albedo plunge to past lows then it's safe to say that snow melted and we are back to previous years meltout dirt?

[BornFromTheVoid]

11 hours ago, tablet said:

So Mr Devonian ,,, yes all graphs start at zero ,, but all the ice gained from last season hasn't disappeared has it ? it's still there , that is what I was trying to demonstrate , and as you can see from the other graphic's ,,nothing is melting at the moment , and there I was thinking I would bring a little happy news to the people that seem very concerned about Greenland , or do you like making people think all the ice is melting ?

let me put a question directly to you , did last season's ice gain disappear ?

What you want is the mass balance, rather than the surface mass. If the amount of snow that falls and melts was the sole determinant of how big the ice sheet gets, Greenland would be much easier to understand!
As it is, processes at the ice edge play a very important role too (ocean melting, glacial flow, drainage calving, etc) so looking at the overall mass balance is better for working out the health of the ice sheet.
 

We may well get the odd years where ice loss plateaus or reverses a little, but the trend is more than clear.

[tablet]

what has a chart from 2002 got to do with what I posted ( readings from yesterday and data from the last year ) ?

the temperature in Greenland yesterday was -20 in the interior and -4 at the coast

 

Edited May 14, 2018 by tablet

[BornFromTheVoid]

13 minutes ago, tablet said:

what has a chart from 2002 got to do with what I posted ( readings from yesterday and data from the last year ) ?

the temperature in Greenland yesterday was -20 in the interior and -4 at the coast

 

You were making comments about the health of the ice sheet...

Quote

but all the ice gained from last season hasn't disappeared has it ? it's still there , that is what I was trying to demonstrate , and as you can see from the other graphic's ,,nothing is melting at the moment 

But you only showed evidence from the surface mass balance, which is highly misleading, thus I posted a graph showing the trend in Greenland mass balance (from 2002 to 2017).  I don't think I was being unreasonable.

[tablet]

so you also think that the gains over the last season just disappeared ? and I'm unreasonable ?

 

 

Edited May 14, 2018 by tablet

[BornFromTheVoid]

2 minutes ago, tablet said:

so you also think that the gains over the last season just disappeared ? and I'm unreasonable ?

 

 

I don't think that. But to determine whether those gains have outstripped the melting (whether they disappeared or not) you need to look at the ice sheet mass balance, not just the surface mass balance.
I'm not sure how else I can explain this?

[tablet]

so your saying  this much ice disappeared , over night

and the following day , it looked like this

just so I have it right , that  is what your saying ? round about 200 Giga tonnes of ice disappeared overnight ?

Edited May 14, 2018 by tablet

[BornFromTheVoid]

26 minutes ago, tablet said:

so your saying  this much ice disappeared , over night

and the following day , it looked like this

just so I have it right , that  is what your saying ? round about 200 Giga tonnes of ice disappeared overnight ?

Surface mass balance is down to snow, rain and surface melting, it doesn't automatically become ice.
I already answered your question also, very clearly!

31 minutes ago, BornFromTheVoid said:

I don't think that. But to determine whether those gains have outstripped the melting (whether they disappeared or not) you need to look at the ice sheet mass balance, not just the surface mass balance.
I'm not sure how else I can explain this?

What do I need to do to get the message through?

Mods, at what point does this silliness count as trolling?

[tablet]

you commented on my post , I answered you , I think your argument is totally unreasonable , that graph is a measure of ICE mass , and I don't think you could remove that much  if you nuked the whole island , and any formula or explanation for that amount of loss is not reasonable  

Edited May 14, 2018 by tablet

[tablet]

and you calling for mods to intervene is also unreasonable

 

[Flash bang flash bang etc]

Maybe the heat from this discussion melted all the ice?  

[tablet]

I merely asked for clarification of what Void had said , I was not abusive or in any way aggressive towards him , I was astounded at his statement , 200 (ish ) giga tonnes of ice is not exactly inconspicuous , you would have thought someone would have noticed it missing

[BornFromTheVoid]

@tablet, I answered your question twice. I even highlighted in bold for you the second time. I'm truly at a loss as to how you are still missing it.

The surface mass balance does not exactly equal ice. It comes from weather model estimates of snowfall over the ice sheet, and similar estimates of rain, sublimation and melting during the thaw periods. What remains, after many years, may eventually turn to ice, but isn't automatically ice.
You don't have to take my word for it, the description of the SMB, from the DMI, who create the graphs you posted, is here: https://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/
A simplified, but clear, snippet from the DMI site is below.

For an ice sheet that neither grows or shrinks, there is at all points averaged over the year a balance between

• the amount of snow that falls and is compressed to ice
• the amount of snow and ice that melts or evaporates (sublimates) and
• the amount of ice that flows away due to the ice motion

The two first contributions make up the surface mass balance. For the ice sheet as a whole, there is a balance between the surface mass balance and the amount of ice that calves into the ocean as icebergs.

 

[tablet]

it was all over the headlines last summer ," Greenland looses 200 Giga Tonnes of ice " but I've shown it put that back on , therefore it's not losing a great deal of anything

[Devonian]

31 minutes ago, tablet said:

it was all over the headlines last summer ," Greenland looses 200 Giga Tonnes of ice " but I've shown it put that back on , therefore it's not losing a great deal of anything

No, snow isn't ice. For heavens sake you surely know it takes time, a lot many years or decades, for snow to be turned, via intermediate 'firn', in glacial ice or an ice cap!

Oh, and you do know snow isn't the same density as ice - right?

[tablet]

ok , how much ice does 200 Giga tonnes of snow make Devonian ?

if 200 giga tonnes of ice flow out , and 200 giga tonnes of snow fall , since Giga tonnes is a measurement of weight , not mass

please enlighten

Edited May 14, 2018 by tablet

[Devonian]

4 minutes ago, tablet said:

ok , how much ice does 200 Giga tonnes of snow make Devonian ?

 

This gives an idea.

[tablet]

appears to be a dead link

[Devonian]

No, actually, I'm thinking this out wrongly - my bad!!! Of course X tonnes of snow weight he same as X tonnes of ice. But, the point is what falls isn't the same as what will accumulate.

BFTV has it right in his last post above.

Edited May 14, 2018 by Devonian

[Methuselah]

X tonnes of snow may fall...some will sublimate, some will get blown into the sea by katabatic gales, and some will melt and then run off as water?

[Devonian]

40 minutes ago, Ed Stone said:

X tonnes of snow may fall...some will sublimate, some will get blown into the sea by katabatic gales, and some will melt and then run off as water?

And I seem to remember a not inconsiderable amount of what accumulates is actually hoar frost?