What is the annual sea level rise due to land erosion?

Radical Rodent posed this question and SandyS found the relevant data.

I would say that we have not found a reliable figure for how much mineral matter moves from land to sea each year. The 75 billion tons figure apparently comes from a single review article. In the absence of more definite information, I would characterise this figure as "somebody's guess". (My intuition suggests that the estimate will be biased in the direction of being greater than the reality.)

It is not stated what proportion of the supposed 75 G tons finishes in the sea and how much finishes elsewhere on the land

"Each year, about 75 billion tons of soil is eroded from the land—a rate that is about 13-40 times as fast as the natural rate of erosion."[62]

[62] Zuazo, Victor H.D. & Pleguezuelo, Carmen R.R. (2009). "Soil-erosion and runoff prevention by plant covers: a review". In Lichtfouse, Eric et al. Sustainable agriculture. Springer. p. 785. ISBN 978-90-481-2665-1.

http://en.wikipedia.org/wiki/Erosion

I have sent a question to the National Oceanography Centre via their website: Hello, I want to find an authoritative estimate of the mass of mineral matter that moves from land into the ocean annually. Please tell me who I should contact for this information. Thank you. Martin A

Taking the 75 billion tons (=76.20 billion tonnes) and SandyS's 90% guess gives 68.6 billion tonnes. Using the guess of 2 g/cm³ density gives 3.43 × 10^10 m³ volume.

The surface area of the oceans has been given as 361,900,000 km sq = 3.6×10^14 m²
http://www.ngdc.noaa.gov/mgg/global/etopo1_ocean_volumes.html

Dividing the volume increment by the area to get the depth increment gives nearly 0.1mm as the annual rise in sea level resulting from land erosion.

What is the accuracy of this figure? I would say "the true figure is probably less than 1mm and is probably greater than 0.001 mm" in view of the following three things being guesses:

- The annual tonnage of land erosion (I assume it is a guess, lacking information otherwise)
- The average density of the lost material
- The proportion of this that ends up in the sea (my intuition says that this is the guess with the greatest uncertainty)