diff --git a/docs/users_guide.log b/docs/users_guide.log
index 198ee5d49116784dc3aeec4062a6e7f27263fb5f..5075cff2231a1dde3717deda20105628d6d6382a 100644
--- a/docs/users_guide.log
+++ b/docs/users_guide.log
@@ -1,6 +1,6 @@
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+This is pdfTeX, Version 3.14159265-2.6-1.40.20 (TeX Live 2019) (preloaded format=pdflatex 2019.11.28)  12 AUG 2022 18:39
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+Output written on users_guide.pdf (9 pages, 164648 bytes).
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diff --git a/docs/users_guide.pdf b/docs/users_guide.pdf
index 2e48b49a3e3c283b72edaaabe95638d87dc10af3..c54a8c6d85917686c8d61e6d0e935a4569c146d8 100644
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diff --git a/docs/users_guide.synctex.gz b/docs/users_guide.synctex.gz
index b9d79467542bf77353acb749211e8685ca2f871a..209442091cf2109bf293290e187763c12b84ab51 100644
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diff --git a/docs/users_guide.tex b/docs/users_guide.tex
index 7e023877a8f2623c95d94328580133bf074c8602..e8038232d7679494df1cd2d163fd519287d325e5 100644
--- a/docs/users_guide.tex
+++ b/docs/users_guide.tex
@@ -360,7 +360,7 @@ give significant speedup \\
 \hline
 \emph{massflux} & The massflux parameterization of convection (Siebesma et al., 2007): 0 - off, 1 - on. \\
 \hline
-\emph{ifrad} & Radiation fluxes at the water surface: 0 - set to zero; 1 - full treatment \\
+\emph{ifrad} & Radiation fluxes at the water surface: 0 - set to zero; 1 - full treatment of surface radiation budget \\
 \hline
 \emph{ifbubble} & Switch for the bubble model: 0 - off (bubbles do not change with depth); 1 - on \\
 \hline
@@ -379,9 +379,9 @@ give significant speedup \\
 \emph{horvisc} & Horizontal viscosity, m$^2$/s, used to damp the 1-st horizontal velocity mode \\
 \hline
 \hline
-\emph{backdiff} & Switch for background diffusivity by Hondzo and Stefan (1993); 1 -- off, 1 -- on \\
+\emph{backdiff} & Switch for background diffusivity: 0 -- off, 1 -- background diffusivity by Hondzo and Stefan (1993); 2 -- background diffusivity from KPP model, based in Ri number, 3 -- constant background diffusivity \\
 \hline
-\emph{backdiff0} & A multiplier in background diffusivity expression by Hondzo and Stefan (1993), relevant if \emph{backdiff}=1; if \emph{backdiff0}$<$0., then a reference value from original paper is used \\
+\emph{backdiff0} & A reference value in background diffusivity, m$^2$/s, expression by Hondzo and Stefan (1993) or KPP model, or a value of constant background diffusivity, relevant if \emph{backdiff}>0; if \emph{backdiff0}$<$0., then the reference values are used \\
 \hline
 \emph{nManning} & Manning's coefficient, relevant for \emph{dyn\_pgrad}=5 \\
 \hline