mar110 lecture #25 hurricane dynamics ii & case studies · the great hurricane of ’38 was...

3 November 2007 mar110_L25_CS_hurricanes_3nov07.docricanes 1

MAR110 LECTURE #25 Hurricane Dynamics II & Case Studies

Figure 25.1 RAINEX Hurricane Measurements The “Hurricane Hunter” trajectories are indicated in the schematics of the spiral-banded hurricanes.

RAINEX HURRICANE MEASUREMENTSRAINEX HURRICANE MEASUREMENTS

KATRINA August 2005KATRINA August 2005 RITA September 2005RITA September 2005

Figure 25.2 Hurricane Trajectories During RAINEX in 2005, the team was able to make measurementsin hurricanes KATRINA and RITA, whose trajectories are given here with an indication of wind speed and category.


Figure 25.3 Hurricane Measurements The “Hurricane Hunter” trajectories are indicated in the schematics of the spiral-banded hurricanes.


HURRICANE Rita WIND MEASUREMENTSHURRICANE Rita WIND MEASUREMENTS

Figure 25.4 Hurricane Rita (2005) Evolution (ABOVE) A time series composite of wind speed and air pressure measurements are compared to (BELOW) an inverted version of the trajectory . Saffir-Simpson scale categories are color-coded.


Rita RAIN MEASUREMENTSRita RAIN MEASUREMENTS

Model Rain ForecastModel Rain Forecast

Figure 24.14 Hurricane Rita (2005) Rain

Figure 25.5 Hurricane Rita (2005) Wind Structure


HURRICANE DAMAGE & SAFFIR SIMPSON SCALEHURRICANE DAMAGE & SAFFIR SIMPSON SCALE

Figure 25.7 Hurricane Wind Damage – Saffir Simpson Scale Hurricanes are categorized according to wind ranges. The cartoons shown typical structure damage to structures for each of the categories. (??)

50 km/hr50 km/hr

250 km/hr250 km/hr150 km/hr150 km/hr 200 km/hr200 km/hr

Figure 25.6 Hurricane Wind Structure In the northern hemisphere the highest winds are on the right hand side of the leading edge of the hurricane (here the upper right quadrant). The speed of the hurricane itself is added to the speed of the wind around the storm when they are both going in the same direction while it is subtracted when going in opposite directions as on the left side of


The Great Hurricane of ’38The Great Hurricane of ’38

was was

“lurking offshore” “lurking offshore” of North Carolina..of North Carolina..

“virtually undetected”“virtually undetected”

on the morning of on the morning of

21 September 1938..21 September 1938..

by late afternoon by late afternoon it was pummeling it was pummeling

Long Island Long Island &&

New England New England

Figure 25.8 The Great New England Hurricane of 1938 stayed offshore as it proceeded northward. It’s presence was reported by a few ships, but otherwise there was little warning as it’s ferocity surprised people on Long Island, where it made first landfall, before pummeling Connecticut and Rhode Island. (GHTW??)

Figure 25.6 Hurricane Damage

Figure 25.7 The Great New England Hurricane of 1938 Two book covers of books dealing with the hurricane of 1938 that did massive damage to the New York and southern New England coastlines. (GHTW, SS)


Great New England Hurricane Northeastern United States, September 21, 1938

D. Longshore Widely regarded as the single most violent tropical cyclone in New England

history, the Great New England Hurricane's 121-mph (195-kph) winds, 186-mph (299-kph) gusts, 8-inch precipitation counts, and cataclysmic 17-foot storm surge claimed more than 600 lives and wrought between $300 million and $400 million in property damage on New York's Long Island, Connecticut, Rhode Island, Massachusetts, New Hampshire, and Vermont.

Originating near the Cape Verde Islands on or about September 13, the Great New England Hurricane was spotted 300 miles east of the Bahamas on the morning of September 19 and abreast of Jacksonville, Florida, on the evening of September 20 - at which point hurricane observers apparently lost track of its progress (see Figure 25.2). Now deepened into a Category 4 tropical cyclone of devastating intensity (a central barometric pressure of 27.85 inches [938 millibars] was recorded aboard the Cunard White Star liner Carinthia on the night of September 20), the storm's distant but threatening presence was discretely noted in the evening editions of major regional newspapers on September 20: a lukewarm hurricane warning that ultimately did lime to prevent the tragic events of the following day.

Suddenly accelerating north-northwest at an average speed of 55 mph (89 kph), the Great New England Hurricane sideswiped North Carolina's sandy Cape Hatteras just after dawn on September 21 and then slammed into western Long Island and southern Connecticut shortly before nightfall on the same day. Fueled by a central pressure of 27.94 inches (946 millibars) at landfall near Milford, Connecticut, the robust eyewall of the Great New England Hurricane churned northwestward, passing along the Connecticut Valley and into western Massachusetts with a degree of meteorological fury rarely before seen in either state. A newspaper reporter on New York's Long Island described the hurricane's onset as possessing "a steady, almost organ-like note of such intensity that it seemed as if the whole atmosphere were in harmonic vibration".

In Providence, Rhode Island, the waters of Narragansett Bay flooded much of the city with 13 feet of debris, stranding hundreds of people on the" upper floors of buildings and on the steps of City Hall. Vulnerable ocean-side towns like Misquamicut and Na-patree Point, Rhode Island, were completely obliterated by the hurricane's surge, their shingle-style cottages and finger-pier marinas reduced to mere driftwood in a matter of minutes. At Connecticut's Wesleyan University, the chapel's stone tower was blown to the ground, and in nearby Stonington five railway coaches belonging to the Bostonian were derailed, swept off a causeway and into a surge-swollen estuary. Despite the heroic actions of the train's crew in safely evacuating most of the 250 passengers aboard, two people were' killed.

In Boston, Massachusetts, some 75 miles east of the eye wall's path, three men drowned· when their fishing trawler capsized in the harbor. At the city's airport, the buckling of a 100-foot-radio tower disrupted air-traffic control operations, while an empty American Airlines DC-2 aircraft was carried several hundred yards by the hurricane's extraordinary fringe gales and dropped in a marsh.

In Springfield, 80 miles southwest of Boston, very close to the hurricane's inland track, some 16,000 trees - many of them ancient hardwoods - were uprooted. More than 4 million bushels of apples were ruined as neighboring orchards were devoured by the


hurricane's insatiable winds. Worcester, a fading textile city east of Springfield, suffered a further decline as

two huge redbrick mills crumbled into dusty clouds, pulling swaying clock towers to the ground with them.

In the nearby town of Hadley, the hurricane's undiminished winds collapsed a tall chimney at Northfield Seminary, fatally crushing two girls in the dormitory below. In adjacent Amherst, falling trees crushed houses, split barns, and formed impromptu dams across rain-swamped streets. A group of freshmen at Amherst College, taking part in an intelligence test during the peak of the hurricane's passage over the Pioneer Valley, reportedly achieved higher scores than any other group in the school's prior history.

In distant New Hampshire, where anemometers recorded gusts of 160 mph (258 kph), the base station and trestle of the scenic cog railway that chugged its way up 6,288 -foot Mount Washington were demolished. Elsewhere in the Granite State, a smoldering rag fire in the town of Peterborough soon turned into a roaring conflagration as the hurricane's fanning winds carried flames from one wooden building to the next. Burning fiercely through the rainy, gust-punctured night, much of the town would, by the following morning, lay in charred ruins.

Sharply recurving northwestward late in the evening of September 21, the Great New England Hurricane blasted across southwestern Vermont and New York's Lake Champlain before dissipating into 50-mph (81-kph) rain squalls over central Canada on the morning of September 22.

Immediately recognized as the worst natural disaster in the region's history, the Great New England Hurricane of 1938 left 600 people dead, with another 100 forever unaccounted for. Many of the 1,750 injured people were critically hurt, while 63,000 were left without shelter. Damage estimates, compiled with great difficulty over the following weeks, revealed a staggering material loss: 4,500 buildings completely destroyed; another 15,139 homes, cottages, and barns seriously damaged; 2,605 boats cast ashore, sunk, or wrecked, with another 3,369 left damaged; 1,475 animals killed, including 1,000 head of cattle and 750,000 chickens; 31,000 telephone poles plucked from the earth, forming a chaotic canopy over more than 25,000 totaled automobiles.


New EnglandNew England Watch Hill, RIWatch Hill, RI

Hurricane Eye PathHurricane Eye PathFigure 25.9 The Great Hurricane of 1938 Trajectory & Site of Major Destruction (GHTW??)


Moore Moore FamilyFamily

“Cottage”“Cottage”NapatreeNapatree PtPt

Watch Hill, RIWatch Hill, RI

Figure 25.10 Watch Hill, RI - Napatree Point – BEFORE THE STORM The Moore family –part of a summertime beach community on Napatree Point in watch Hill, RI - was still at their summer cottage on the morning of 21 September 1938. Like the other residences there, the Moore Family cottage was built on a simple foundation on top of the sand only a couple feet above sea level with little protection from storms or rough sea. (GHTW??)


Fort Road Fort Road NapatreeNapatree PointPoint Watch Hill RIWatch Hill RI

AFTERAFTER

BEFOREBEFORE

““..30 ft waves..30 ft wavesswept the colony swept the colony

bare!”bare!”

Figure 25.11 When the storm surge hit in the early afternoon of 21 September 1938, the Moore cottage and all of the others on Napatree Point were completely washed off of their foundations….in some cases carrying the occupants to their deaths. By some miracle, the remaining Moore occupants were able to ride their disintegrating house across Little Narragansett Bay to safety on Osbrook Point. (GHTW??)


Figure 25.13 Osbrook Point, Connecticut - 22 September 1938. The graveyard for many of the Napatree Point cottages and some of their occupants. (??)

Figure 25.12 Storm’s Fury Obliterates the Napatree CommunityThe map shows the trajectories of the debris of the various cottages from Napatree Point across Little Narragansett Bay - mostly to Osbrook Point in Connecticut. (??)


Location MapsLocation Maps

New EnglandNew England

Jamestown, RIJamestown, RI

Figure 25.15 Other locations of hurricane damage. (GHTW??)

JAMESTOWN READINGS

Before Hurricane of ‘38Before Hurricane of ‘38 After Hurricane of ‘38After Hurricane of ‘38

Figure 25.14Geography – BEFORE and AFTER The hurricane breached both the sand spit and Napatree Point and redistributed the sand in the area. (GHTW??)

mar110 lecture #25 hurricane dynamics ii & case studies · the great hurricane of ’38 was...

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