High Resolution WRF Simulations for the Tel-Aviv Metropolitan Area Reveal the Urban Fingerprint in the Sea-Breeze Hodograph

We implement and verify for the first time four Weather Research and Forecasting model urban configurations, focused on the coastal metropolitan area of Tel-Aviv (MTA) using updated landuse and morphological maps. We analyze the mesoscale summertime flow and the urban canopy (UC) role in the occurrence of different hodograph dynamics observed within MTA at night. These events may be significant in air quality research. The four configurations-bulk (MM), single-layer (SLUCM), multilayer (BEP), and BEP coupled with the building energy model-reproduce the observed diurnal temperature and wind cycles, with similar 10-m wind direction bias and RMSE ( less than or similar to 15 degrees and similar to 30 degrees, respectively), with preference for MM and SLUCM at night. However, the SLUCM shows the lowest skill for the 10-m wind speed (WS) (bias and RMSE >= 1 m s(-1)), and the BEP shows the largest underestimation of the 2-m temperature, similar to-2.5 degrees C. In the SLUCM, the WS increases over an UC and with increasing building heights. These results call for a reexamination of the SLUCM WS parameterization. The simulations show that at night, a convergence line (CL) builds up with the urban heat island, downstream of the NW flow. West of the CL, the wind continues flowing from the sea, and rotates anticlockwise to form a nonelliptical sea-breeze hodograph. Removing MTA UC restores an elliptical hodograph. East of the CL, the UC supports an elliptical hodograph with a clockwise rotation through the NE sector, previously reported as dynamically unstable. We expect such wind hodograph dynamics within similar coastal metropolitan areas.

Automated summary

This study implemented and verified four urban configurations of the Weather Research and Forecasting model for the coastal metropolitan area of Tel-Aviv, focusing on the mesoscale summertime flow dynamics and the role of urban canopy in hodograph dynamics at night. The simulations showed that the MM and SLUCM configurations were more accurate for diurnal temperature and wind cycles, while SLUCM exhibited lower skill in wind speed and BEP underestimated 2-m temperature. The study suggests a need for reexamination of the SLUCM wind speed parameterization.