Cyclogenesis nov98

Rapid Cyclogenesis and Societal Impacts of November Great Lakes Cyclones: 

Rapid Cyclogenesis and Societal Impacts of November Great Lakes Cyclones Stacie Bender & Nicki Hickmon April 23, 2001

Project Outline: 

Project Outline Application of Theory Petterssen-Sutcliffe Cyclone Development Effects of Lakes on the Cyclones Diabatic Heating Effects Effects of Cyclones on the Lakes Waves Societal Impacts of Great Lakes Cyclones Sinking of the Edmund Fitzgerald (November 1975)

Application of Theory: 

Application of Theory Petterssen-Sutcliffe Cyclone Development Development measured in terms of local vorticity change at sea level Qo/t = AQ – (R/f)2[(g/R) AT + S + H] 4 terms contribute to the local vorticity change: Vorticity Advection (AQ) Thickness Advection (AT) Adiatbatic Influence (S) Diabatic Effects (H)

P-S: VORTICITY ADVECTION: 

P-S: VORTICITY ADVECTION Development at the surface is a function of vorticity advection at the level of nondivergence (LND). Positive Vorticity Advection at ~500 mb above the position of the surface low will aid in cyclone development.

P-S: 500 mb VORTICITY ADVECTIONEta Analysis for 11/09/98 1200 UTC : 

P-S: 500 mb VORTICITY ADVECTION Eta Analysis for 11/09/98 1200 UTC L (996 mb)

P-S: VORTICITY ADVECTIONEta Analysis for 11/10/98 1200 UTC: 

P-S: VORTICITY ADVECTION Eta Analysis for 11/10/98 1200 UTC L (972 mb)

P-S: THICKNESS ADVECTION: 

P-S: THICKNESS ADVECTION Surface development is also a function of thickness advection ahead of the surface system. Thickness advection patterns dictate where the surface low moves toward and away from. Warm thickness advection supports cyclogenesis. Surface pressure falls in warm thickness advection areas because of: Hypsometric reasoning Enhanced divergence ahead of the upper and mid level trough if the curvature is sharp Cold thickness advection opposes cyclogenesis. Surface pressure rises in cold thickness advection areas because of: Hypsometric reasoning Enhanced convergence behind the upper and mid level trough if the curvature is sharp The surface low propogates towards the falling pressures that were created by warm thickness advection.

P-S: THICKNESS ADVECTIONEta Analysis for 11/09/98 1200 UTC: 

P-S: THICKNESS ADVECTION Eta Analysis for 11/09/98 1200 UTC L

P-S: Thermal AdvectionEta Analysis for 11/09/98 1200 UTC: 

P-S: Thermal Advection Eta Analysis for 11/09/98 1200 UTC WAA CAA L

P-S: THICKNESS ADVECTIONEta Analysis for 11/10/98 1200 UTC: 

P-S: THICKNESS ADVECTION Eta Analysis for 11/10/98 1200 UTC L

P-S: Thickness/Thermal AdvectionEta Analysis for 11/10/98 1200 UTC: 

P-S: Thickness/Thermal Advection Eta Analysis for 11/10/98 1200 UTC WAA CAA CAA WAA L

P-S: Adiabatic Influences: 

P-S: Adiabatic Influences Development of surface low is contingent upon potential energy being available to the system. Cyclones that ingest dry, stable air rarely develop. This provides a large negative term to the LHS of the P-S Development Equation. Ingest of dry, stable air prevents cyclogenesis. Cyclones that ingest moist, unstable air CAN develop, depending on other factors. The ingest of moist, unstable air is a NECESSARY, but not SUFFICIENT condition for cyclogenesis. If moist, unstable air is ingested, the “gate” is opened, and cyclogenesis can proceed.

PS: Adiabatic Influences: 

PS: Adiabatic Influences Moist, unstable air crept closer to the center of the surface low during the period of 1200 UTC 09 November 1998 to 1200 UTC 10 November 1998 (period of rapid development). During this time, the central pressure of the cyclone went from 996 mb to 972 mb. 24 mb drop in 24 hours = “Bombogenesis.” Cyclones rarely “bomb out” over land. Many ingredients came together in the right place, at the right time.

P-S: Adiabatic InfluencesEta Dewpoint Analysis for 11/09/98 1200 UTC: 

P-S: Adiabatic Influences Eta Dewpoint Analysis for 11/09/98 1200 UTC L 8 C Dewpoint ahead of developing cyclone.

P-S: ADIABATIC INFLUENCESEta Dewpoint Analysis for 11/10/98 1200 UTC: 

P-S: ADIABATIC INFLUENCES Eta Dewpoint Analysis for 11/10/98 1200 UTC L 12 C Dewpoint ahead of developing cyclone.

P-S Diabatic Heating : 

P-S Diabatic Heating Warm surface produces vertical motion and cyclonic vorticity Warm Moist Surface from Lakes Emit radiant energy Provide sensible heat Provide latent heat

P-S SUMMARY: 

P-S SUMMARY During a 24 hour period (1200 UTC 9-10 November 1998), the central pressure of the cyclone went from 996 mb to 972 mb. 24 mb drop in 24 hours = “Bombogenesis.” Cyclones rarely “bomb out” over land. Many ingredients came together in the right place, at the right time. Vorticity Advection patterns Thickness Advection patterns Moist, unstable air Diabatic heating provided by the Great Lakes Diabatic heating provided by the Great Lakes served to further intensify and deepen the cyclone.

Great Lakes: 

Superior Michigan Huron Erie Ontario Saginaw Bay Great Lakes

Effects of Great Lakes on Colorado Cyclones: 

Effects of Great Lakes on Colorado Cyclones September - November Cyclones Accelerate while crossing the Great Lakes Region Cyclones Intensify while crossing the Great Lakes Region

Effects of Great Lakes on Colorado Cyclones: 

Effects of Great Lakes on Colorado Cyclones September - November Intensify prior to entering and whithin the Great Lakes region Weaken and decelerate while exiting the region * Results from: Angel & Isard 1997 and Petterssen, 1957

Effects of Cyclones on the Lakes: 

Effects of Cyclones on the Lakes Making Waves: Effect of Wind on Water Size of wave depends on: Wind Speed: stronger wind = larger waves Duration of the Winds: Longer Duration = larger waves Fetch: Larger stretch of water = larger waves

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes Significant Wave Height: Defined as the average height of the one-third highest waves Generally what an experienced observer would most frequently report Wave heights forecasted and recorded are the significant wave height. SWH is constrained by fetch SWH of ~26 feet are about as high as waves can build on Superior, no matter how strong the wind, or how long it blows. However…..

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes While the significant wave height is generally what is observed and recorded, it is very important to note that the rare peak waves can be as much as twice the significant wave height. This would create 50 foot waves on Lake Superior.

Effects of Cyclone on Great Lake Region: 

Effects of Cyclone on Great Lake Region Lakes Michigan 15 – 20 ft waves Lake Superior 20 ft waves Wider lake forms larger waves

Effects of Cyclone on Great Lake Region: 

Effects of Cyclone on Great Lake Region SW 69mph wind gusts pushed water from west Lake Erie toward New York and Ontario Lake Erie - 4ft below normal

Effects of Cyclone on Great Lake Region: 

Effects of Cyclone on Great Lake Region Seiche - an oscillation of the surface of a landlocked body of water (as a lake) that varies in period from a few minutes to several hours

Effects of Cyclone on Great Lake Region: 

Effects of Cyclone on Great Lake Region Saginaw Bay Winds pushed 5 feet of water from Saginaw Bay into Lake Huron Stranded duck hunters walked 3 miles to original shoreline

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes Waves in Lake Superior in November 1998 and 1975? 1998: Rock of Ages Lighthouse and other observation points reported long periods of gale force winds of 34-47 knots, with gusts over 50 knots. Likely produced significant wave heights of 20 to 25 feet

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes 1975: Sustained east winds of 34-48 knots were forecasted for the night of the Fitzgerald sinking Fitzgerald reported NE 52 knot winds at 1:00 am Soon after, the NWS upgraded the gale warning to a storm warning, forecasting NE winds of 48-63 knots and waves of 8-15 feet. At 7:00 am, the Fitzgerald reported NE winds at 35 knots and 10 foot waves (intensifying low pressure center was over Marquette, MI at this time).

Effects of Cyclones on Lakes: 

Effects of Cyclones on Lakes Waves would eventually play the ultimate role in the sinking of the SS Edmund Fitzgerald.

SS Edmund Fitzgerald: 

SS Edmund Fitzgerald Specs: Length: 729 feet Width: 79 feet Height: 39 feet Weight: 13,632 tons Load Weight: 26,116 tons of taconite (iron)

SS Edmund Fitzgerald: 

SS Edmund Fitzgerald The Fitzgerald left Superior, WI on November 9, 1975 while the weather was calm. As weather forecasts of northeasterly winds came in, the captains of the Fitzgerald and SS Arthur M. Anderson decided to change their course. A northward course near the Canadian shore would protect the ships from waves generated by a large fetch.

SS Edmund Fitzgerald: 

SS Edmund Fitzgerald

SS Edmund Fitzgerald: 

SS Edmund Fitzgerald However, on the afternoon of the 10th, the winds shifted to northwesterly. The ships were no longer protected by land. Steady winds at 43 knots and waves of 12-16 feet were reported by the Anderson. Fitzgerald reported damage and a list.

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes

Effect of Cyclones on Lakes: 

Effect of Cyclones on Lakes

SS Edmund Fitzgerald: 

SS Edmund Fitzgerald

Theories for Fitzgerald Sinking: 

Theories for Fitzgerald Sinking Capsizing by large waves 10 to 12 feet of water on its deck. Continuous flooding via leaking hatches Fitzgerald ran into a wave, cargo and water rushed forward, driving the ship into the lake. Waves picked up the ship by the ends and the ship broke in half.

November 9-10, 1975: 

November 9-10, 1975 Sank in Lake Superior due to flooding Significant wave heights were up to 25 feet

Sinking of the Edmund Fitzgerald: 

Sinking of the Edmund Fitzgerald

Advances Due to Casualty: 

Advances Due to Casualty A direct result of the sinking of the Edmund Fitzgerald was the installation of buoys on the Great Lakes. In part, the loss of life in the region, 1868 and 1869, Congress formed a National Weather Service

Data Available in the Great Lakes Region:1975 vs. 1998: 

Data Available in the Great Lakes Region: 1975 vs. 1998 Advances in : Numerical Weather Prediction Observational Data Set 1975: no buoys on the Great Lakes 1998: 3 buoys and 4 automated weather stations on Lake Superior (more data points on other Lakes as well) Remote Sensing: Radar Satellite

Data Available in the Great Lakes Region:1975 vs. 1998: 

Data Available in the Great Lakes Region: 1975 vs. 1998 Advances in Communication between ships and ships and shore: 1975: VHF radio or MF radio telephone Any marine warning, statement or forecasts were given by the Coast Guard on VHF radio Today: VHF Radio FAXback service Digital Marine Weather Dissemination System NOAA Weather Radio Dial-A-Buoy Websites and Internet

References: 

References Angel, James R., Scott A. Isard. An Observational Study of the Influence of the Great Lakes on the Speed and Intensity of Passing Cyclones. Monthly Weather Review. 125: 2228-2237 Fortner, Rosanne W., Daniel W. Jax. The Great Lakes Triangle. Ohio State University Research Foundation, 1985. Freighter Images: http://www.crh.noaa.gov/mqt/fitzgerald National Transportation Safety Board Marine Accident Report SS Edmund Fitzgerald Sinking in Lake Superior. Report Number: NTSB-MAR-78-3 Petterssen, Sverre. Weather Analysis and Forecasting, Volume 1, Second Edition. McGraw – Hil, 1956. Sinking of the Edmund Fitzgerald: http://cimss.ssec.wisc.edu/wxwise/fitz.html Storm Warning: Advancements in Marine Communications and Forecasting (MQT NWS): http://www.crh.noaa.gov/mqt/fitzgerald/index.htm U.S. Army Corps of Engineers Satellite Image: http://www.greatlakes.net/gis/maps