Impact of effective roughness length on mesoscale meteorological simulations over heterogeneous land surfaces in taiwan

Fang Yi Cheng, Chin Fang Lin, Yu Tzu Wang, Jeng Lin Tsai, Ben Jei Tsuang, Ching Ho Lin

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

The Weather Research and Forecasting (WRF) modeling system obtains the aerodynamic roughness length (20) from a land use (LU) lookup table. The effective aerodynamic roughness length (~0eff) was estimated for the island of Taiwan by considering the individual roughness lengths (20/) of the underlying LU types within a modeling grid box. Two 2 datasets were prepared: one using the Zqj from the default LU lookup table and the other using the observed Zqj for three LU types (urban, dry cropland and pasture, and irrigated cropland and pasture). The spatial variability of the z0eff distribution was higher than that of the LU table-based Zq distribution. Three WRF sensitivity experiments were performed: (1) dominant LU table-based Zq (namely, SI), (2) 2^ estimated from the default 2q/ (namely, S2), and (3) 2Qeff estimated from the observed Zqj (namely, S3). Comparisons of the thermal field, temperature, and surface sensible and latent heat fluxes revealed no significant differences among the three simulations. The wind field overestimation and surface momentum flux underestimation in SI were reduced in S2 and S3, and these improvements were more prominent over areas with highly heterogeneous land surface conditions.

Original languageEnglish
Article number805
JournalAtmosphere
Volume10
Issue number12
DOIs
StatePublished - 1 Dec 2019

Keywords

  • Effective roughness length
  • Land use
  • Surface fluxes
  • Surface heterogeneity
  • Wrf

Fingerprint

Dive into the research topics of 'Impact of effective roughness length on mesoscale meteorological simulations over heterogeneous land surfaces in taiwan'. Together they form a unique fingerprint.

Cite this