Richardson number

[cherokeeflyboy]

Can any one explain the "Richardson Number" as it relates to the turbulence forecast?

 

[bbchien]

Can any one explain the "Richardson Number" as it relates to the turbulence forecast?

Now don't glaze over, but go here: http://amsglossary.allenpress.com/glossary/search?id=richardson-number1
The number is dimensionless, and relates the buoyant stability (the tendancy of parcels of air of equal density to equilibrate, to the steepness of the vertical shear of the wind locally.

It, in a more mathematical way than the "lifted index" is an engineering model of the tendancy of one tendancy (equilibrium) to overcome windshear.

You won't see many pilots preflight this, nor briefers...who I do not believe understand this quotient.

 

[cherokeeflyboy]

I kinda understand the definition, however was wondering how this is applied to turb. forecast. see attached

 

[bbchien]

I kinda understand the definition, however was wondering how this is applied to turb. forecast. see attached

In this model, since the denominator represents how much vertical shear there is and the numerator represents how much buoyant stability there is, 1/10 is mighty unstable air. Watch out if you are living in Edmonton at this moment- if there is any moisture in the air, you'll get t-storms. If not, just lots of turb.

Remember, you get t-storms when at about 15,000 feet enough saturated moisture turns to droplets, releasing lots of latent heat, heating the column of air and "voila!" droplets at FL 430.

 

[cherokeeflyboy]

Thanks Bruce!, I was confusing myself looking at the numbers like the "k" index.
Dont know how accurate this model is, but something to consider.. KD