GRACE terrestrial water-storage anomalies: Danube low water vs Kati Thanda–Lake Eyre high water

[t1303]

I am trying to understand the GRACE terrestrial-water-storage anomaly product in relation to two current hydrological conditions: exceptionally low Danube water levels and historically high water levels at Kati Thanda–Lake Eyre.

GRACE measures changes in Earth's gravity field resulting from mass redistribution and expresses the land signal as terrestrial water-storage anomalies relative to a reference period.

My question is specifically about mass, rather than water depth or river level.

What should the GRACE terrestrial-water-storage anomaly show over the Danube basin during an extreme low-water event, and over the Lake Eyre basin during an extreme flooding event?

Given the observed extreme low-water conditions in the Danube and the historically high water level at Kati Thanda–Lake Eyre, I would expect the Danube basin to show a substantially more negative (red) anomaly and the Lake Eyre basin to show a substantially more positive (blue) anomaly.

I have independently estimated the relevant volumes of the Danube valley and Lake Eyre basin, and the magnitudes are comparable. Can GRACE detect the corresponding changes in terrestrial water mass, and should they be visible in the anomaly map?

I am trying to understand whether the GRACE-derived mass anomalies are consistent with the independently observed hydrological conditions.