A reader remarked on our discussion of dangerous sea level rise, asking:
Where is all that ice that is dissapearing [sic] from glaciers and land based ice sheets going to end up and why if the decline of glaciers and land based ice sheets is accelerating will sea level rise not accelerate with it?
I asked for a reference to quantify “all” the ice that’s disappearing and to verify the ice melt acceleration. So he sent some, then mentioned studies of the decade-long GRACE (Gravity Recovery and Climate Experiment) satellite data that show ice loss accelerating in Greenland and West Antarctica. Note that’s not the whole continent; I don’t know why he focussed on the WAIS — perhaps West Antarctica is known to be accumulating ice, which doesn’t fit his narrative.
Anyway, he said West Antarctica is losing 118 gigatons* per year and Greenland is losing 303 gigatons.
But is that a little or a lot? The activists don’t tell us, they just mention “gigatons” and wait for us to gasp with shock. But it’s easy for us to get a sensible guide to the importance of this amount of ice loss, and Wikipedia is a good tool. For objective data, many people acknowledge Wikipedia as a reliable source, though one must be more discerning with contentious topics.
Volume of a gigaton of ice
1 gigatonne (Gt) = 1 cubic kilometre (km3) – Climate Sanity
Volume of Antarctic ice
26.5 million km3 – Wikipedia
Volume of Greenland ice
2.85 million km3 – Wikipedia
This is troublesome, since conflicting studies are readily available, some showing net Antarctic loss, some showing net gain. Our reader cited the following figures from NASA, which are difficult to argue with. But it turns out that the losses are trivial and untroubling, as I shall show.
Several studies have shown that different remote sensing methods for studying ice sheet mass balance agree well. GRACE’s record, spanning over a decade, shows that the ice loss is accelerating in Greenland and West Antarctica. Greenland has shed, on average, 303 gigatons of ice every year since 2004, while Antarctica has lost, on average, 118 gigatons of ice per year, with most of the loss coming from West Antarctica. Greenland’s ice loss has accelerated by 31 gigatons of ice per year every year since 2004, while West Antarctica has experienced an ice mass loss acceleration of 28 gigatons per year.
Time for ice to vanish
Antarctica: 225,000 years
Greenland: 9,400 years
Finally, for a meaningful comparison, I thought I’d calculate the mass of annual precipitation over Greenland. It turns out to be quite a bit.
Average annual Greenland precipitation
821 mm – Climate Data
Area of Greenland
2.166 million km3 – Wikipedia
Volume of Greenland precipitation
Mass of Greenland precipitation
1778 Gt (1,788,000,000,000 tons)
Divide 1778 km3 by 303 km3 (the annual ice loss) and it turns out, ladies and gentlemen, that every year nearly six times the claimed annual ice loss falls on Greenland as rain, snow and hail. I put it to you that the Greenland ice sheet will be with us for many thousands of years.
Nobody can credibly claim that this reported ice loss should cause concern—the loss is just too small, even minuscule. Scientists who imply concern must be knowingly misleading us—or don’t they know the size of Greenland or Antarctica? Most of them avoid clear statements, rather choosing vague expressions such as “could”, “may”, “is in danger of”, “during the Paleocene” (or insert favourite epoch) and similar weasel phrases that give them some small defence if questioned that they never actually committed themselves to the lies told by warmist activists so it’s not their fault, really it isn’t.
But by the same token they remain open to accusations of never having corrected the lies spread far and wide by activists, though they clearly knew better.
In any case, when we know the true scale of these physical climate changes, we have a sturdy defence against spending large amounts of public money that are sorely needed for real social problems.
* US (short) tons, UK (long) tons and metric tonnes: there’s a difference, to be sure, but not so much as to derail the argument made here for the insignificance of ice loss.