Just for interest is the GRACE-FO data for AIS+GIS ice mass loss since 2002.
Total mass loss = over 17 mms of sea level rise (very close to 1 mm per year)
I thought annual rise was ~3 mm. What is the other two...thermal expansion? Glacier melt?
The linked references answer your question as other contributions (both negative and positive) to eustatic SLR include:
1. Terrestrial water storage (TWS) both natural and manmade;
2. Thermostatic;
3. Ice caps and mountain glaciers;
4. Groundwater depletion
5. Dam Impoundments
6. Barystatic.
Also, I note that there is a glacial isostatic adjustment (GIA) factor.
Frederikse, T., Landerer, F., Caron, L. et al. The causes of sea-level rise since 1900. Nature 584, 393–397 (2020). https://doi.org/10.1038/s41586-020-2591-3
https://www.nature.com/articles/s41586-020-2591-3
Abstract: "The rate of global-mean sea-level rise since 1900 has varied over time, but the contributing factors are still poorly understood. /snip/... Our results reconcile the magnitude of observed global-mean sea-level rise since 1900 with estimates based on the underlying processes, implying that no additional processes are required to explain the observed changes in sea level since 1900."
The claim that there are "no additional processes" is disputed by Iz and Shum in "The certitude of a global sea level acceleration during the satellite altimeter era", 2020, in J. Geod. Sci., open access.
DOI:
https://doi.org/10.1515/jogs-2020-0101"Abstract: Recent studies reported a uniform global sea
level acceleration during the satellite altimetry era (1993–
2017) by analyzing globally averaged satellite altimetry
measurements. Here, we discuss potential
omission errorsthat were not thoroughly addressed in detecting and estimating
the reported global sea level acceleration in these
studies. Our analyses results demonstrate that the declared
acceleration in recent studies can also be explained
equallywell by alternative kinematic models based on previously
well-established multi-decadal global mean sea
level variations of various origins, which suggests prudence
before declaring the presence of an accelerating
global mean sea level with confidence during the satellite
altimetry /SA/ era."
They perform a thorough statistical analysis of previous research on the satellite data for SLR, and compares to tidal gauge data (TG). The time series display severe autocorrelation in the residuals, and they try to track down how this can be understood and explained. They write:
"There may be other error sources, omission errors,
which occur due to various contributors/confounders of
physical origin on sea level variations that are ignored in
the kinematic models..." Specifically, they critically analyze the two recent studies by Nerem, et, al. (2019), and Ablain, et, al. (2018), where both find an acceleration in SLR.
"Sea level variations are multi-causal. Some of the effects
are global isostatic adjustment, periodic changes in sea
levels induced by wind, pressure, external forcing such as
of lunar solar origin, and thermosteric effects of warming
oceans, or they are eustatic in nature. The effects may be
secular, episodic, transient, periodic at semi-annual, annual,
interannual, decadal, or decadal and multidecadal
time scales, all contributing to sea level anomalies. These
effects are also local, regional, and could be global. Yet,
the two recent studies that reported global sea level accelerations,
by Nerem et al, (2018) and Ablain et al. (2019),
ignored the contribution of these multidecadal effects in
their analyses in detecting the GMSL acceleration. /..,./
The omission of the effect of potential confounders including
a potential jerk or multidecadal sea level variations
(Ablain at al., 2019), or using a conjecture that they will
average out because of the superior global coverage of SA
by Nerem at al. (2018) is
a leap of faith without evidence in
quantifying a GMSL acceleration and its uncertainty using
globally averaged SA time series. Moreover, conducting
projections as in Nerem at al. (2018) without ascribing
proper uncertainties to the model estimates have no
meaning."
Basically, they find that the claimed acceleration in SLR can be equally well be explained by different natural cycles of various frequency, see attached figure. They say that "it would be misleading to declare a global sea level acceleration during the SA
era with an acceptable uncertainty and make predictions
if the origin of the perceived acceleration is likely to be an
unmodeled periodicity or periodicities."
Caption to figure: "Fig. 8. The amplitudes and the standard errors (error bars) are the
weighted averages of the estimated amplitudes across 27 TG stations.
All weighted averages are statistically significant. Weights
are the inverse variances of the amplitude estimates at each TG station,
which are regionally correlated with a spatial correlation of
0.80 among the stations (estimated from their residuals) but not
correlated among the regions (Iz et al., 2018)."