| 1556 | | * 'circular': Text goes here |
| 1557 | | * 'newton': Text goes here |
| 1558 | | * 'lookup': Text goes here |
| | 1556 | * ''''circular'''': A fast method that was the previous default in PALM. Here, the Obukhov length is calculated based on the values of t* (and q*) calculated from the previous time step. This circular calculation leads to a time lag in the Obukhov length and is thus inaccurate.\\\\ |
| | 1557 | * ''''newton'''': The Obukhov length is calculated by means of the Richardson number and a Newton iteration algorithm. This method yields correct values of the Obukhov length, but it is slower than the 'circular' and 'lookup' methods. Furthermore it cannot be vectorized.\\\\ |
| | 1558 | * ''''lookup'''': This method is similar to the Newton iteration method, but the iteration is avoided by creating a lookup table of the Obukhov length against Richardson number at model start. This method yields accurate values of the Obukhov length while being less computationally expensive compared to the Newton iteration method. However, it cannot be used in case of varying roughness lengths (unless the roughness lengths are locally homogeneous on each processor domain). |
