Ground truth analysis of Western Antarctic ice loss

The press release: JPL | News | West Antarctic Melt Rate Has Tripled: NASA-UC Irvine

The paper submitted for publication can be downloaded from the link and full of good stuff! For example, they even accounted for glacier rebound, the upwelling of land when the over-cover ice thins. Here is a map showing the area:

The last is critical because it means the four independent sources have been analyzed so future metrics can be used with confidence. In earth observations, the most critical step is ground-truth calibration. In this case, the ability to get similar results from four independent sources significantly improves our ability to get and trust Antarctic metrics with fewer sources.

As for the mechanisms, the paper doesn't offer any speculation. But having better metrics, it would help if our Aussi friends would visit to do some multi-year, underwater surveys. Then add some underwater metrics with sets of water temperature and salinity measurements. For good measure, seismic sensors, an array, to measure any under-ice, volcanic activity that has yet to be detected by a surface eruption. This would be a great place to do more detailed, Antarctic measurements.

Bob Wilson

 

Drill baby, drill. <grins>

The real problem is the ice motion. But it looks like there are mountains on either side that might be thinner or rock accessible.

Bob Wilson

 

The curious density behavior of water, 5C/39F being the densest, leads to a curious water based melting:

The 'deep' water being warmer than the ice, it undermines the base of the glaciers. But as this water melts the ice, it becomes colder, less dense, and rises. It then becomes exposed to Antarctic surface temperatures and being a little fresher, able to more easily freeze on the surface expanding the floating, surface ice. This sea water based melt would have the same area as the speculated, geothermal melting, the base and especially the sides of the glacier below sea level.

The following radar map shows the ground profile of one of the glacier beds:

This is well within the range of warmed water layers found by the Argo network.

So what would help now would be:

1. Salinity, temperature, and current profiles at the sea edge of the glaciers. Perhaps some Argo probes with enough smarts to stay in an area and avoid glacier entanglement. It might require an 'ice aware' version.
2. Survey the underside of the ice sheet close to the ground line. Perhaps a longer range version of the Aussi robots to look for evidence of new ice formation on the floating side of the ice sheet. The bottom should show significant, ice dendrites from refreezing of fresh, cold water and the underside of the ice sheet . . . the underwater version of hoar frost freezing.
3. Passive, seismic sensors, an array, to determine if there is just shallow, ice breaking at the ground line or something deeper. The amount of heat required to make a significant, base melt would require geothermal motion, magma. This typically comes with deep, earthquake activity. So it needs to be a long-term, array monitoring. It may also provide a way to map the ground line.

But first my apologies:

I tend to start from the NASA based web sites and that led to a prepublication version of the paper. Hopefully an editor fixed the last sentence of the conclusion section that has at least two, possibly three sentences in:

Average reading grade level, 24.3, and Flesch-Kincaid Reading Ease, -9.3.

My version:

We have shown how four independent, satellite measurements converge to the nearly identical results. In the future, this approach will allow faster tracking of glacier metrics and updates to ice sheet models.​

Average reading grade level, 12.2, and Flesch-Kincaid Reading Ease, 42.5.

Non-English, native authors would be helped by using this web site to improve readability:
Readability-Score.com - Free Online Readability Calculator - Flesch Kincaid, Gunning Fog and more ...

Bob Wilson