Cyclone Hamish (2009)
Encyclopedia
Severe Tropical Cyclone Hamish (BoM designation: 17U; JTWC
Joint Typhoon Warning Center
The Joint Typhoon Warning Center is a joint United States Navy – United States Air Force task force located at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii...

 designation: 18P) was the first Category 5 cyclone within the Australian region since Cyclone George
Cyclone George
Severe Tropical Cyclone George was the third tropical cyclone to affect the Australian region and the first to affect Western Australia in 2007...

 in 2007. The seventeenth tropical low and eight named storm of the 2008–09 Australian region cyclone season, Hamish developed out of an area of low pressure
Low pressure area
A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence which occur in upper levels of the troposphere. The formation process of a low-pressure area is known as...

 on 4 March near the Cape York Peninsula
Cape York Peninsula
Cape York Peninsula is a large remote peninsula located in Far North Queensland at the tip of the state of Queensland, Australia, the largest unspoilt wilderness in northern Australia and one of the last remaining wilderness areas on Earth...

. The storm rapidly developed into a Category 1 cyclone on the Australian intensity scale the next day. On 6 March, an eye
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...

 developed and Hamish strengthened into a Category 3 cyclone. Deep convection
Atmospheric convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference, layer in the atmosphere. Different lapse rates within dry and moist air lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to...

 formed around the eye, fuelling further intensification which allowed the storm to become a Category 5 cyclone late on 7 March.

Meteorological history

Severe Tropical Cyclone Hamish was first identified on 4 March 2009 by the Bureau of Meteorology (BoM) as a tropical low over the Coral Sea
Coral Sea
The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

. Drifting westward, the system steadily became better defined, developing convective
Atmospheric convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference, layer in the atmosphere. Different lapse rates within dry and moist air lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to...

 banding features
Rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands can be stratiform or convective, and are generated by differences in temperature. When noted on weather radar imagery, this precipitation elongation is referred to as...

 later that day. Situated in an area favouring tropical cyclone
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...

 development, characterised by warm waters, low wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...

 and upper-level diffluence, the low was able to quickly strengthen. The following day, the Joint Typhoon Warning Center
Joint Typhoon Warning Center
The Joint Typhoon Warning Center is a joint United States Navy – United States Air Force task force located at the Naval Maritime Forecast Center in Pearl Harbor, Hawaii...

 (JTWC) issued a Tropical Cyclone Formation Alert
Tropical Cyclone Formation Alert
A Tropical Cyclone Formation Alert is a bulletin released by the U.S. Navy-operated Joint Typhoon Warning Center in Honolulu, Hawaii or the Naval Maritime Forecast Center in Norfolk, Virginia, warning of the possibility of a tropical cyclone forming from a tropical disturbance that has been...

 as convection wrapped around the centre of circulation
Low pressure area
A low-pressure area, or "low", is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence which occur in upper levels of the troposphere. The formation process of a low-pressure area is known as...

 and an anticyclone
Anticyclone
An anticyclone is a weather phenomenon defined by the United States' National Weather Service's glossary as "[a] large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere"...

 developed over the system, allowing for good outflow
Outflow (meteorology)
Outflow, in meteorology, is air that flows outwards from a storm system. It is associated with ridging, or anticyclonic flow. In the low levels of the troposphere, outflow radiates from thunderstorms in the form of a wedge of rain-cooled air, which is visible as a thin rope-like cloud on weather...

. Hours later, the BoM classified the low as Tropical Cyclone Hamish as the storm began to moved southward in response to a mid-level ridge
Ridge (meteorology)
A ridge is an elongated region of relatively high atmospheric pressure, the opposite of a trough....

 situated to the east. Shortly thereafter, the JTWC also began monitoring Hamish as a tropical storm.

Not long after being classified a tropical cyclone, Hamish began to undergo rapid intensification
Rapid deepening
Rapid deepening, also known as rapid intensification, is a meteorological condition that occurs when the minimum sea-level atmospheric pressure of a tropical cyclone decreases drastically in a short period of time. The National Weather Service describes rapid deepening as a decrease of...

, quickly becoming a severe tropical cyclone, a storm with winds exceeding 120 km/h (75 mph), on 6 March. Deep convection continued to develop around a well-defined low pressure centre, allowing for further strengthening. Additionally, satellite images depicted that an eye
Eye (cyclone)
The eye is a region of mostly calm weather found at the center of strong tropical cyclones. The eye of a storm is a roughly circular area and typically 30–65 km in diameter. It is surrounded by the eyewall, a ring of towering thunderstorms where the second most severe weather of a cyclone...

 had begun developing within the storm. A steady south-easterly track was fully established by this time as the ridge to the east and a trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...

 over central Australia prevented westward movement. Based on radar
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...

 observations, the eye of Hamish was about 28 km (17.4 mi) in diameter by 7 March. Later that day, the storm further intensified into a Category 5 cyclone on the Australian intensity scale, becoming the first to do so since Cyclone George
Cyclone George
Severe Tropical Cyclone George was the third tropical cyclone to affect the Australian region and the first to affect Western Australia in 2007...

 in 2007. Later that day, Hamish attained its peak intensity with winds of 215 km/h (130 mph) along with a barometric pressure of 925 mbar
Bar (unit)
The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...

 (hPa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...

; 27.32 inHg). At the same time, the JTWC assessed the storm to have nearly become a Category 5 equivalent on the Saffir–Simpson Hurricane Scale; peak one-minute sustained winds were estimated at 250 km/h (155 mph).

At its peak, Hamish was a small cyclone; gale-force winds covered an area roughly 440 km (273.4 mi) and the radius of outermost closed isobar
Radius of outermost closed isobar
style="float: right; clear: right; background-color: transparent; margin-left: 0em"|The radius of outermost closed isobar is one of the quantities used to determine the size of a tropical cyclone. It is determined by measuring the radii from the center of the storm to its outermost closed isobar...

 was about 260 km (161.6 mi). After maintaining Category 5 status for roughly 24 hours, Hamish began to weaken as the interaction with coastal Australia and increased wind shear took their toll. Late on 8 March, an eyewall replacement cycle had begun to take shape, allowing the storm to maintain Category 4 intensity for the following few days. By 10 March, the storm finally began to show signs of steady weakening as shear continued to increase due to an approaching trough from the west. Later that day, the storm began to slow as it moved within a region of light steering currents. Substantial loss of convection took place during this time, causing Hamish to weaken below severe tropical cyclone status by 11 March.

Convection failed to redevelop over the centre of Hamish throughout 11 March, prompting the JTWC to issue their final advisory on the system. The BoM also declared Hamish a remnant low around the same time; however, they continued to monitor the remnant system as it began to turn towards the northwest due to a ridge south of the storm. The remnants of Hamish tracked in an erratic, north-westward direction over the following few days, backtracking over where it had been days earlier. The system finally dissipated on 14 March off the coast of Australia, never having made landfall.

Preparations

Following the formation of Hamish as a tropical low on 4 March, a Cyclone Watch was issued for areas between Cape Melville
Cape Melville
Cape Melville is a headland on the eastern coast of the Cape York Peninsula. To its west lies Princess Charlotte Bay. It is part of the Cape Melville National Park....

 and Bowen
Bowen, Queensland
Bowen is a town on the eastern coast of Queensland, Australia. At the 2006 census, Bowen had a population of 7,484.-Geography:Bowen is located on the north-east coast of Australia, at exactly twenty degrees south of the equator. In fact, the twentieth parallel crosses the main street...

. Early the next morning, a Cyclone Warning was declared for areas between Cape Melville and Cardwell
Cardwell, Queensland
Cardwell is a tropical coastal town in northeastern Queensland. It is located at the southern extremity of the Cassowary Coast. At the 2006 census, Cardwell had a population of 1,250. The Bruce Highway National Highway 1 and the North Coast railway line are the dominant transport routes;...

 and the watch was extended to Hayman Island
Hayman Island
Hayman Island is the most northerly of the Whitsunday Islands, part of the Cumberland Islands, which are located off the coast of Central Queensland, Australia at...

 and later to Mackay
Mackay, Queensland
Mackay is a city on the eastern coast of Queensland, Australia, about north of Brisbane, on the Pioneer River. Mackay is nicknamed the sugar capital of Australia because its region produces more than a third of Australia's cane sugar....

 and St Lawrence
St Lawrence, Queensland
St Lawrence is a small town in Queensland, Australia, located north of Brisbane and off the Bruce Highway. It is part of the Isaac Regional Council local government area. At the 2006 census, St Lawrence and the surrounding area had a population of 195....

. As Hamish travelled parallel to the coastline, the watches and warnings shifted towards the south, with the warnings between Cape Melville and Cape Flattery being cancelled during the afternoon of 6 March. New Cyclone Warnings were issued for areas between Cape Flattery and Lucinda
Lucinda, Queensland
Lucinda is a coastal town in the state of Queensland, Australia, located at the southern entrance to Hinchinbrook Channel near the town of Ingham. A sugar-exporting town, Lucinda is noted for its 6km-long sugar jetty, the world's largest bulk sugar loading facility...

. Due to heavy rains produced by the outer bands
Rainband
A rainband is a cloud and precipitation structure associated with an area of rainfall which is significantly elongated. Rainbands can be stratiform or convective, and are generated by differences in temperature. When noted on weather radar imagery, this precipitation elongation is referred to as...

 of the cyclone, Flood Warnings were issued for areas between Cooktown
Cooktown, Queensland
Cooktown is a small town located at the mouth of the Endeavour River, on Cape York Peninsula in Far North Queensland where James Cook beached his ship, the Endeavour, for repairs in 1770. At the 2006 census, Cooktown had a population of 1,336...

 and Townsville
Townsville, Queensland
Townsville is a city on the north-eastern coast of Australia, in the state of Queensland. Adjacent to the central section of the Great Barrier Reef, it is in the dry tropics region of Queensland. Townsville is Australia's largest urban centre north of the Sunshine Coast, with a 2006 census...

.

On 7 March, Queensland Premier Anna Bligh
Anna Bligh
Anna Maria Bligh is an Australian politician and the Premier of Queensland since 2007. The 2009 Queensland state election was the first time a female-led political party won or retained state or federal government in Australia...

 signed a Declaration of Disaster Situation which permitted Australian officials to evacuate residents from the areas most at risk from Cyclone Hamish. People were advised to take every action necessary to prepare for the storm and be ready to evacuate on short notice. Although in the direct path of Hamish, no evacuations took place on Hayman Island
Hayman Island
Hayman Island is the most northerly of the Whitsunday Islands, part of the Cumberland Islands, which are located off the coast of Central Queensland, Australia at...

. The 3,000 residents and tourists on Hamilton Island
Hamilton Island
Hamilton Island may refer to:* Hamilton Island , Australia** Hamilton Island Race Week, keelboat regatta** Great Barrier Reef Airport, formerly Hamilton Island Airport* Hamilton Island , Canada...

 were advised to have the preparations complete by nightfall. Most of the boats on the island were removed from the water in attempts to protect them from rough seas. Non-essential staff and tourists were evacuated from the small resort islands of South Molle Island
South Molle Island
South Molle Island, part of the Whitsunday Islands, is a resort island in the Whitsunday section of the Great Barrier Reef Marine Park in Australia. The hilly island has numerous bays and inlets accessible by 16 km of walking tracks, with 420 ha protected in the Whitsunday Islands...

 and Long islands. in the Whitsundays to shelters located on larger islands. A state of emergency was also declared for several coastal areas. On 8 March, an estimated 1,000 tourists were evacuated from Fraser Island and more evacuations also took place on Lady Elliot Island
Lady Elliot Island
Lady Elliot Island is the southern-most coral cay of the Great Barrier Reef, Australia. The island lies north-east of Bundaberg and covers an area of approximately . The island is home to a small eco resort and an airstrip, which is serviced daily by flights from Bundaberg, Hervey Bay,...

 and Heron Island. Trains leaving Brisbane and Cairns were cancelled due to the storm for several days.

Impact

As a tropical low, Hamish produced heavy rains over Far north Queensland
Far North Queensland
Far North Queensland, or FNQ, is the northernmost part of the Australian state of Queensland. The region, which contains a large section of the Tropical North Queensland area, stretches from the city of Cairns north to the Torres Strait...

, amounting to at least 300 mm (12 in) in localised areas. Cairns, located along the periphery of the storm, recorded 92 mm (3.6 in). Between 10am and 2pm local time on 7 March, Mackay recorded 148 mm (5.8 in) of rain. An additional 136 mm (5.3 in) fell the following day. In combination with high tide, Hamish produced a 6.3 m (20.6 ft) tide in Mackay, flooding some streets. No injuries were reported due to the flooding but debris was washed out to sea. An estimated 2,000 residents were left without power along the south-east coast of Queensland. The rough seas produced by the storm severely injured a member of the coast guard during his patrol around Noosa.

A 4.5 m (14.7 ft) tide flooded parts of Yeppoon, but no major damage was reported. Officials in Mackay estimated that damages would total in the tens of thousands. The Sunshine Coast in Queensland
Sunshine Coast, Queensland
The Sunshine Coast is an urban area in South East Queensland, north of the state capital of Brisbane on the Pacific Ocean coastline. Although it does not have a central business district, by population it ranks as the 10th largest metropolis in Australia and the third largest in...

 sustained significant beach erosion and at least 30 trees were knocked down. A pier sustained damage and another was partly destroyed. Severe erosion on Bribie Island and further erosion could create a break in the island, creating a passage to the Pumicestone Passage
Pumicestone Passage
Pumicestone Passage, also known as the Pumicestone Channel, is a narrow waterway between Bribie Island and the mainland in Queensland, Australia...

. The Golden Beach Progress Association chairman, Mick Graham, feared that if this happened, the structure of the island and passage would change. On the Discovery Coast, constant beach erosion washed away numerous trees and some walkways, with officials estimating that millions of tonnes of debris were in the water.

A trawler caught in rough seas produced by the storm sent out a distress signal as it became overcome by the storm. Rescue attempts to retrieve the three crew members were hampered by Hamish and were called off but expected to resume of 10 March. Nearly three days following the sinking of the trawler, officials called off the search and presumed that the two missing fishermen had drowned after finding empty life jackets and an un-deployed life raft. Severe erosion also caused the northern part of Fraser Island to become nearly inaccessible as it left the bedrock exposed. The Environmental Protection Agency stated that it was possible for light vehicles to continue along the normal route during low tide but were recommended to take the two hour detour. Throughout the Queensland coastline, damage from Hamish amounted to A$60 million (US$46 million).

Great Barrier Reef

Along the storm's 500 km (310.7 mi) track parallel to the Queensland coastline, the eye passed over a substantial portion of the Great Barrier Reef
Great Barrier Reef
The Great Barrier Reef is the world'slargest reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometres over an area of approximately...

, resulting in some of the worst damage to the area in recent history. Unlike most cyclones which travel from east to west in the region, impacting only a small area of the reef, Hamish moved alongside the reef for nearly its entire existence. The Bureau of Meteorology estimated that about a quarter of the area was impacted by the storm, with some parts being within 30 km (18.6 mi) of Hamish's eye when it was a Category 5 cyclone. According to post-storm surveys of the reef, the damage done to the coral was extensive, with upwards of 70% losses in the hardest hit spots. Nearly all of the exposed coral was destroyed by turbulent waters; however, in places where the coral was slightly sheltered, there was little to no damage. Some areas were completely stripped of all living tissues, leaving only bare limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

. According to preliminary estimates, it would take the reef between eight and fifteen years to recover from Hamish if nothing hampers growth.

The Swain sector of the Great Barrier Reef, once considered one of the most densely coral-populated regions of the reef, was nearly completely destroyed by the storm. Research times found little in the way of coral remaining on exposed surfaces. Due to the severity of the damage, the Queensland Seafood Industry Association requested that the reef be declared a disaster zone between Bowen and Wide Bay. Fish previously living in the area were no longer present by 25 March. Great Barrier Reef Marine Park Authority chairman Russel Reicheld stated that "Hamish did more damage to the reef than any other natural disaster in recent history."

Oil spill

A 183 m (600 ft) cargo ship called the MV Pacific Adventurer
MV Pacific Adventurer
Pacific Mariner formerly, MV Pacific Adventurer is a 1123 TEU geared multi-purpose container ship that gained notoriety after causing Queensland's largest oil spill on the east coast of Australia in March 2009. The ship is owned by Swire Shipping and registered in Hong Kong...

was carrying 60 containers of ammonium nitrate when it encountered rough seas produced by Hamish, while located about 13 km (8 mi) east of Cape Moreton
Cape Moreton
Cape Moreton is a rocky headland located at the north eastern tip of Moreton Island in South East Queensland, Australia. The surrounding area is part of the Moreton Island National Park. 5 km north-west of Cape Moreton is Flinders Reef....

. The incident occurred near to a marine animal park, which is home to endangered species. Around 3:15 a.m. EST on 11 March, 31 of the containers spilled into the sea along with a large amount of heavy fuel, causing the surface of the water to become slick. Officials attempted to contain the oil spill, but the rough seas prevented easy containment. Environmentalist warned that the oil could have a significant impact on the local wildlife. One of the containers damaged the hull as it fell off the ship. After divers inspected the ship for the source of the spill, two holes were found. One, located just above the waterline, was 10 mm (0.4 in) long 15 mm (0.6 in) wide. The second and larger hole was located underneath the ship. The length of it was about 1 m (1.3 ft) and the width was 300 mm (11.8 in).

An estimated 620 tonnes of ammonium nitrate and 250 tonnes of fuel spilled out of the ship. The spilled fuel covered an area about 5.5 km (3.4 mi) long and 500 m (1,600 ft) wide. Although ammonium nitrate is not harmful to the environment, the high concentration was proposed to have the capability of suffocating marine life in the area. The oil spill continued to expand in coverage, affecting five beaches and forcing several other beach areas to shut down. By 13 March, the oil covered an estimated 40 km (25 mi) of coastline. On 13 March, Anna Bligh stated that the crew members of the ship were likely understating the amount of fuel that leaked out due to the vast size and depth of the spill, with some beaches recording the oil being inches thick.

Aftermath

Health officials hoped that rains from Hamish would help to reduce an ongoing dengue fever
Dengue fever
Dengue fever , also known as breakbone fever, is an infectious tropical disease caused by the dengue virus. Symptoms include fever, headache, muscle and joint pains, and a characteristic skin rash that is similar to measles...

 outbreak; however, little rainfall reached the coast, allowing further growth of the disease. On 10 March—following improved weather—rescue teams resumed searching for the three missing fishermen. During the second rescue attempt, one of the fishermen was found alive but alone in a large swell about 259 km (161 mi) northeast of Yeppoon, Queensland
Yeppoon, Queensland
Yeppoon is a coastal resort town situated in Central Queensland, Australia. Located on Keppel Bay, at the 2006 census, Yeppoon had a population of 13,284.-Geography:...

. The rescuers were able to find him when he turned on an Emergency Position Indicating Radio Beacon, which he originally thought was a stick. This beacon allowed the rescuers to pinpoint his location, though the other two fishermen reportedly did not have these beacons. On 16 March, a memorial service was held for the two fishermen who were lost at sea. About 200 people who knew the two men attended the service; many of whom signed a book honoring the fishermen.

Following the oil spill, Queensland Premier Anna Bligh
Anna Bligh
Anna Maria Bligh is an Australian politician and the Premier of Queensland since 2007. The 2009 Queensland state election was the first time a female-led political party won or retained state or federal government in Australia...

 declared two islands and parts of the Sunshine coast as disaster areas. Cleanup efforts were reportedly going to cost at least $100,000 a day and last more than a week as the oil continued to spread. The company in charge of the cargo ship is faced with a possible $1.5 million in fines for the incident. Several search parties have been sent to the spill area to attempt to find the potentially explosive materials that were in the 31 containers. Press reports stated that if the ammonium nitrate were to mix with the heavy fuel, it could ignite the ammonium nitrate and cause a large explosion. If the chemical did not react with the fuel, but still leaked out, marine life could be threatened by large blooms in algae. A team of 88 people were sent out to begin the cleanup process and another 58 were expected to join within the following days. On Moreton Island, a total of 290 people are working to clean up the oil with most of them focusing on Middle Creek and Cape Moreton. Even though hundreds of people were working on cleaning the spill, the average amount cleaned each day was 1 km2 (0.6 mi2). It was not until May of that year that Moreton Island was finally cleared of oil. The cleanup effort was undertaken by 2,500 people and led to the removal of roughly 3,000 tonnes of contaminated sand.

The estimated cost to clean the island was put at A$
Australian dollar
The Australian dollar is the currency of the Commonwealth of Australia, including Christmas Island, Cocos Islands, and Norfolk Island, as well as the independent Pacific Island states of Kiribati, Nauru and Tuvalu...

5 million ($3.2 million USD). Following the environmental disaster, the company is being fined an additional A$248.6 million ($163.5 million USD). In July 2010, the captain of the vessel which spilled the oil was brought to court on charges of disposing oil in coastal waters. In light of the worldwide infamy the ship received, a commercial decision was made by the Swire shipping company to rename the cargo ship the MV Pacific Mariner.

In June 2009, the name Hamish was retired from the list names in the Australian Basin; it was later replaced with Herman.

See also

  • Timeline of the 2008–09 Australian region cyclone season
    Timeline of the 2008–09 Australian region cyclone season
    This timeline documents all the storm formations, strengthening, weakening, landfalls, extratropical transitions, as well as dissipation during the 2008–09 Australian region cyclone season. The 2008–09 Southern Hemisphere Tropical Cyclone year started on 1 July 2008 and ended on 1 July 2009. The...


External links

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