Cyclone Mahina Category 5 cyclone (Australian scale) Formed Unknown Dissipated 5 March 1899 Highest winds 10-minute sustained: 205 km/h (125 mph) Lowest pressure 914 mbar (hPa); 26.99 inHg (Lowest recorded pressure) Fatalities 400-410 Areas affected Far North Queensland, Australia Part of the Pre-1970 Southern Hemisphere tropical cyclone seasons
Cyclone Mahina struck Bathurst Bay, Australia and the surrounding region with a devastating storm surge on 4 March 1899, killing over 400 people, the largest death toll of any natural disaster in Australian history.
Intensity
Tropical cyclone Mahina hit on 4 March 1899. It was a Category 5 cyclone, the most powerful of the tropical cyclone severity categories. In addition, Mahina was perhaps one of the most intense cyclones ever observed in the Southern Hemisphere and almost certainly the most intense cyclone ever observed off the East Coast of Australia in recorded history. Mahina was named by Government Meteorologist for Queensland Clement Wragge, a pioneer of naming such storms.
Contemporary reports vary considerably in the reported lowest barometric pressures. The pressure recorded on the schooner Olive are reasonably consistent in showing the lowest pressure recorded on her: 29.60 to 29.10 or between 29.00 and 29.10 inches A further variant was "during the lull in the hurricane the barometer on the Olive recorded 29.70 to 29.10" (no units are given).
Most sources record the schooner Crest of the Wave observation as 27 inches. e.g. Another reports 26 inches. More modern reports of a 18 inch observation on a vessel in the eye of Mahina seem to have no relationship to contemporary records.
Whittingham has accepted the 29.1 and 27 inches reports from the Olive and the Crest of the Wave respectively seemingly unaware of the discrepant reports. He has estimated the track of the cyclone from the damage reports, placing it directly over the position of the Crest of the Wave. The Olive was to the north and missed the centre. A pressure there of 29.1 is consistent with that of the Crest of the Wave of 27 given the separation. He calculates the centre pressure, standardised for temperature, as 914 mb (hPa).
In comparison tropical cyclone Tracy which devastated Darwin in 1974 had a central pressure of 950 hPa. Barometric pressure this low at mean sea level is also a likely cause and strong indicator of why cyclone Mahina created such an intense, phenomenal and claimed world record height storm surge of the likes not seen since.
Impact
Within an hour, the Thursday Island based pearling fleet anchored in the bay or nearby, was either driven onto the shore or onto the Great Barrier Reef or sunk at their anchorages. Four schooners and the manned Channel Rock lightship were lost. A further two schooners were wrecked but later refloated. Of the luggers, 54 were lost and a further 12 were wrecked but refloated. Over 30 survivors of the wrecked vessels were later rescued from the shore however over 307 were killed, mostly immigrant non-European crew members.
A storm surge, variously reported as either 13 metres or 48 feet high, swept across Princess Charlotte Bay then inland for about 5 kilometres, destroying anything that was left of the Bathurst Bay pearling fleet along with the settlement. Eyewitness Constable J. M. Kenny reported that a 48 ft (14.6 m) storm surge swept over their camp at Barrow Point atop a 40 ft (12 m) high ridge and reached 3 miles (5 km) inland, the largest storm surge ever recorded. However Nott and Hayne reviewed the evidence for this. They modelled the surge based on the 914 hPa central pressure and found the surge should only have been 2 to 3m height. They also surveyed the area looking for wave cut scarps and deposits characteristic of storm events but found none higher than 5 m. Of the 48 ft surge they suggest the ground level cited may not be correct, or that terrestrial flooding was also involved.
The cyclone continued southwest over Cape York Peninsula, emerging over the Gulf of Carpentaria before doubling back and dissipating on 10 March.
A memorial stone to "The Pearlers" who were lost to the cyclone, naming 11 Europeans but only citing "over 300 coloured men" for the other seamen, was erected on Cape Melville. The disaster is also commemorated in the Anglican church on Thursday Island.
Reference: http://en.wikipedia.org/wiki/Mahina_Cyclone_of_1899 Downloaded 15 May 2012
World Storm Surge Records By Jeffrey Masters, Ph.D. — Director of Meteorology, Weather Underground, Inc.
The Bathurst Bay Cyclone, also known as Tropical Cyclone Mahina, which struck Bathurst Bay, Australia on March 5, 1899, is generally credited with the world record for storm surge. The cyclone's storm surge is variously listed at 13 - 14.6 meters (43 - 48 feet). The Category 5 cyclone was a monster--with sustained winds in excess of 175 mph and a central pressure between 880 and 914 mb. Mahina killed at least 307 people, mostly on pearling ships, and was the deadliest cyclone in Australian history. The eyewitness account of Mahina's record storm surge was provided by Constable J. M. Kenny, who journeyed to Barrow Point on Bathurst Bay to investigate a crime on the day of the storm. While camped on a ridge 40 feet above sea level and 1/2 mile inland, Kenny's camp was inundated by a storm wave, reaching waist-deep. On nearby Flinders Island, fish and dolphins were found on top of 15 meter (49 foot) cliffs. However, an analysis by Nott and Hayne (2000) found no evidence of storm-deposited debris higher than 3 - 5 meters above mean sea level in the region. They also cited two computer storm surge simulations of the cyclone that were unable to generate a surge higher than three meters.
Indeed, Bathurst Bay is not ideally situated to receive high storm surges. The Great Barrier Reef lies just 20 - 40 km offshore, and the ocean bottom near the bay is not shallow, but steeply sloped. Both of these factors should conspire to keep storm surges well below the record 13 - 14.6 meters reported. The authors concluded that the actual surge from the Bathurst Bay Cyclone may have been 3 - 5 meters. The observed inundation at 13 meters elevation, plus the observation of dolphins deposited at 15 meters above sea level could have been caused by high waves on top of the surge, they argue. Waves on top of the surge (called "wave run-up") can reach five times the wave height at the shore for steeply fronted coasts like at Bathurst Bay. Since waves in the Bathurst Bay Cyclone could easily have been 3 meters, 15 meters of wave run-up on top of the surge is quite feasible. Since wave run-up doesn't count as surge, the status of the 1899 Bathurst Bay Hurricane as the world record holder for storm surge is questionable. However, the event is certainly the world record holder for the high water mark set by a tropical cyclone's storm surge, an important category in its own right.
Figure 1. Satellite image of Bathurst Bay, Queensland Province, Australia. The record 43 - 48 foot storm surge wave occurred on Barrow Point, marked by an "x" on the map above. Image credit: NASA.
Figure 2. Track of the 1899 Bathurst Bay cyclone. Bathurst Bay is located at the point where the 914 mb pressure is listed. Image credit: Whittingham, 1958.
See also ‘WACANDO Mohara’.
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