Test results using the NOAH LSM in the operational HWRF system

The operational HWRF system has been run operationally at NCEP using a physics package very similar to the GFDL Hurricane model since its 2007 implementation. The land model used is a simple one layer slab model identical to that of the GFDL model. The model predicts only the surface land temperature while the moisture is fixed to the initial state of the GFS analysis system. The NOAH LSM is a viable alternative in the WRF system and is the land model of choice in both the GFS and NAM operational systems at NCEP. Soil moisture as well as soil temperature are dependent variables and runoff is a routine output from this system. As an additional benefit, the runoff from the LSM can be used to drive a basic stream flow model.

Several test cases have been investigated. Preliminary results indicate that rainfall patterns are more realistic using the NOAH LSM. Differences with/without the LSM will be done with hurricane-specific objective verification. In addition the overall critical track and intensity statistics will be compared with/without the LSM. Preliminary results indicate positive impacts using the NOAH LSM in HWRF.