Richardson number and stability

In TurbSim, the RICH_NO is 0 for neutral atmospheric stability, >0 for stable and <0 for unstable.
However I find a Richardson number calculator using the critical Richardson number of 0.25 as the separation. … index.html

I suppose I misunderstood something.

The critical Richardson number is the theoretical upper limit for turbulence to exist. It is different than the separation between the unstable/neutral/stable atmosphere.

Sir, i am reading the Turbsim manual it is written there for the IEC kaimal model the RICH_NO =0 , a neutral atmospheric stability .and in the examples file which i downloaded from the site using a IEC kaimal model with a RICH_NO= 0.5. then what is the difference in them . Is there any effect of RICH_NO when we are using a IEC kaimal model ?

The RICH_NO input parameter (as well as everything else in the Non-IEC Meteorological Boundary Conditions section) is ignored in the IEC spectral models. Text in the summary file will indicate that the Gradient Richardson number is 0 for the IEC models, regardless of what the input file says.

Thanks a lot sir . well i also find it yesterday after posting this :slight_smile: