New Zealand Journal of Marine and Freshwater Research abstracts

---

M99019
Received 7 April 1999; accepted 22 March 2000

Wind wave characteristics at Lake Dunstan, South Island, New Zealand

JONATHAN C. ALLAN^*
ROBERT M. KIRK

Department of Geography
University of Canterbury
Private Bag 4800
Christchurch, New Zealand
email: r.kirk@regy.canterbury.ac.nz

^*Present address: Oregon Department of Geology and Mineral Industries, Coastal Field Office, 313 SW 2nd, Suite D, Newport, OR 97365, United States. email: jonathan.allan@dogami.state.or.us

Abstract  Information on wave statistics, seasonal characteristics, and their distribution about lacustrine shorelines is virtually non-existent. The absence of such data limits the effective management of lake shores where issues of shoreline erosion are no less significant than on open ocean coasts. Results from instrumentally measured waves during seven storm events in 1995 are presented for the Clutha Arm of Lake Dunstan, South Island, New Zealand. The significant wave height ranged from 0.07 to 0.57 m with a mean of 0.28 m, whereas the maximum wave reached 1.05 m. Peak spectral wave periods ranged from 1.7 to 3.6 s with a mean of 2.46 s. The largest and most destructive waves are observed along the southern shore of the Clutha arm where fetch lengths are at their maximum. These waves exhibit the longest and widest range of periods and are generally the steepest waves, making them highly erosional at the shore. Correlations of waves with those predicted by NARFET, a deepwater wave-hindcasting computer model, revealed reasonable predictions of the wave height (R = 0.77-0.81), particularly for sites exposed to longer fetches, while the correlations with the wave period were lower (R = 0.56-0.69). Wave hindcasting indicates that the wave regime in the Clutha Arm is bi-directional, with most waves arriving from the north or south. Findings from Lake Dunstan have important implications for larger lakes located throughout New Zealand, where considerably larger waves can be expected to occur during severe storm events.

Keywords  Lake Dunstan; high-frequency waves; wave measurements; wave statistics; wave climate; hindcasting

New Zealand Journal of Marine and Freshwater Research, 2000, Vol. 34: 593-595

0028-8330/00/3404-0593 $7.00 (c) The Royal Society of New Zealand 2000

PDF file of entire paper: medium quality (1510K); (scanned from paper original: notes about this process)

---

This year's abstracts | Journal home page | All abstracts | Publishing home page