A comparison study of two regional atmospheric models over the Mackenzie Basin /

• Main Author: Mati, Iriola.
• Format: Thesis
• Language: English
• Published: McGill University 2006
• Subjects: Atmospheric Sciences; Mackenzie River; Mackenzie Basin; Mackenzie river
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97963

We compare the results of two regional atmospheric models, Canadian Regional Climate Model (CRCM) and Mesoscale Compressible Community Model (MC2) at a mesoscale resolution of 51 km, using 5 cases with different synoptic characteristics over the Mackenzie River Basin. CRCM has physics appropriate for coarse resolution typical of climate models, while MC2 is a mesoscale model with fine resolution physics. The results of both models are largely similar, indicating CRCM physics is able to reproduce mesoscale features. There are however differences. CRCM has stronger and expanded warm and cold bias at low levels compared to MC2. We identified surface initialization and coastal topographic precipitation as two processes responsible for these differences. The underprediction of precipitation over the western slopes of the Rockies is related to the cold bias found at the lee of the mountain barrier in CRCM. Furthermore, our results suggest that the use of different cloud schemes is another factor causing differences between the models.