A mass-conserving and multi-tracer efficient transport scheme in the online integrated Enviro-HIRLAM model

TY - JOUR

T1 - A mass-conserving and multi-tracer efficient transport scheme in the online integrated Enviro-HIRLAM model

AU - Sørensen, Brian

AU - Kaas, Eigil

AU - Korsholm, Ulrik S.

PY - 2013/7/22

Y1 - 2013/7/22

N2 - In this paper a new advection scheme for the online coupled chemical-weather prediction model Enviro-HIRLAM is presented. The new scheme is based on the locally mass-conserving semi-Lagrangian method (LMCSL), where the original two-dimensional scheme has been extended to a fully three-dimensional version. This means that the three-dimensional semi-implicit semi-Lagrangian scheme which is currently used in Enviro-HIRLAM is largely unchanged. The HIRLAM model is a computationally efficient hydrostatic operational short-term numerical weather prediction model, which is used as the base for the online integrated Enviro-HIRLAM. The new scheme is shown to be efficient, mass conserving, and shape preserving, while only requiring minor alterations to the original code. It still retains the stability at long time steps, which the semi-Lagrangian schemes are known for, while handling the emissions of chemical species accurately. Several mass-conserving filters have been tested to assess the optimal balance of accuracy vs. efficiency.

AB - In this paper a new advection scheme for the online coupled chemical-weather prediction model Enviro-HIRLAM is presented. The new scheme is based on the locally mass-conserving semi-Lagrangian method (LMCSL), where the original two-dimensional scheme has been extended to a fully three-dimensional version. This means that the three-dimensional semi-implicit semi-Lagrangian scheme which is currently used in Enviro-HIRLAM is largely unchanged. The HIRLAM model is a computationally efficient hydrostatic operational short-term numerical weather prediction model, which is used as the base for the online integrated Enviro-HIRLAM. The new scheme is shown to be efficient, mass conserving, and shape preserving, while only requiring minor alterations to the original code. It still retains the stability at long time steps, which the semi-Lagrangian schemes are known for, while handling the emissions of chemical species accurately. Several mass-conserving filters have been tested to assess the optimal balance of accuracy vs. efficiency.

U2 - 10.5194/gmd-6-1029-2013

DO - 10.5194/gmd-6-1029-2013

M3 - Journal article

SN - 1991-959X

VL - 6

SP - 1029

EP - 1042

JO - Geoscientific Model Development

JF - Geoscientific Model Development

IS - 4

ER -