[labster]

Immediate? Certainly not. Weather models do have incomplete information, but the equations are approximated by Taylor series (1st to 3rd order, depending on the model, last time I checked).

It's possible that this can explain some of the differences between models or ensemble runs... but you have to realize that most of the error comes from incomplete data in the initial and boundary conditions. Looking for weather model effects is like looking for relativistic effects in automobiles.

[m_mueller]

Almost. Most models use some variations of Runge-Kutta approximation, to third order usually.

Edit: typos

[tanderson92]

Convergence, or at least consistency and order, of Runge-Kutta methods is shown via Taylor series, so I don't see the problem or why the GP is only "Almost" correct.

[thethirdone]

The Runge-Kutta methods are not a Taylor series though. So "almost" is apt.

[labster]

Geez guys, I chose a term that I thought most people would be more likely to understand. I realize that some of us have worked a lot more on numerical methods, but other hackers never made it past Calculus 2.

[thethirdone]

I wouldn't have corrected you. I think your comment was fine.

> I realize that some of us have worked a lot more on numerical methods, but other hackers never made it past Calculus 2.

While that didn't occur to me, I do appreciate trying to keep things accessible.

[m_mueller]

Did you take offense from my comment? All I wanted is to set people on the right track if they want to find more information about how NWP is implemented.