Energy balance and synoptic climatology of a melting snowpack in the Southern Alps, New Zealand

✍ Scribed by Neale, S. M.; Fitzharris, B. B.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 458 KB
• Volume: 17
• Category: Article
• ISSN: 0899-8418
• DOI: 10.1002/(sici)1097-0088(19971130)17:14<1595::aid-joc213>3.0.co;2-7

✦ Synopsis

Snow melt is calculated at 1780 m a.s.l., near the Main Divide of the Southern Alps, using a bulk aerodynamic energy balance approach. Results are related to melt measured directly using a lysimeter and to synoptic weather patterns. Measurements are taken half hourly, over a 38 day period from the start of the spring melt season. Melt values at the site average 10 mm day 71 but vary from less than 1 mm day 71 to 63 mm day 71 . The energy balance model overestimated measured melt by 8 per cent. The synoptic situation exerts a strong in¯uence on the magnitude of melt. Melt is highest during north-westerly storms, and three such days contributed one-third of the total melt recorded during the ®eld season. Melt is also high during anticyclones. Different synoptic situations generate distinctive energy budgets, with radiation dominating during large-scale anticyclonic patterns, but sensible heat ¯ux also is important during north-westerly circulation patterns. Distinct pulses of melt, each lasting a period of about 1 week, re¯ect the cyclical passage of troughs and anticyclones across New Zealand.