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To learn more, checkout these Web sites:
www.glerl.noaa.gov/www.oar.noaa.gov/www.glerl.noaa.gov/seagrant/
glwlphotos/Seiche/
Your Erie Times-News hasimportant information about theweather and Lake Erie marineconditions every day. Findthe following: Thetemperature for theday, amount ofprecipitation, windspeed, waves, watertemperature and lakelevel. Keep track of thesefor a week and then plotthem on a graph.
What: Visiting scientist lecture, “The Coyotes of Presque Isle,” byTracy GrazianoWhen: Tonight at 7 p.m.Where: The Tom Ridge Environmental CenterFor more information, contact: Jeanette Schnars at 835-6975 orvisit www.RegSciConsort.com
What: Presque Isle After Dark program, “Night walk at Erie BluffsState Park”When: Saturday, Jan. 31, 6 to 8 p.m. If you are not sure how to get tothe Bluffs, meet the naturalist at the Tom Ridge EnvironmentalCenter; departure is at 5:30 p.m. Bring a flashlight. Dressappropriately for the outdoors. The walk will be about one mile long.Fore more information, contact: Brian Gula, environmentaleducation specialist, 217-9632
What: Presque Isle Little Naturalist program, “Critters under cover,”for children ages 3 to 6 accompanied by an adult. Be prepared to beoutdoors for the full hour.When: Wednesday, Feb. 4, from 1 to 2 p.m.Where: Meet at the Rotary Pavilion to explore Presque Isle forestsand discover the critters that hide under logs and in other habitats.After the program, join us for hot cocoa at the Ranger Station andwarm up by the fire. No fee. No registration required.For more information, contact: Emily Borcz, environmentaleducation specialist, 838-2454
What: Family fishing at Presque Isle State Park, sponsored by thePennsylvania Department of Conservation and Natural Resources,the Pennsylvania Fish and Boat Commission and the SONS of LakeErie.Where: The Rotary Pavilion at the East Pond,When: Saturday, Feb. 14, from 11 a.m. to 3 p.m. The SONS will becooking up hot dogs. All equipment is provided. No fee. Noregistration. Appropriate for all ages. Dress appropriately for theoutdoors. No ice that day, no problem. We will still fish in WaterworksPond with regular gear.For more information, contact: Brian Gula, environmentaleducation specialist, 217-9632
What: Build your own pair of traditional wooden snowshoesWhere: Tom Ridge Environmental Center.When: Saturday, Feb. 21, from 9 a.m. to 3 p.m.Cost: for the workshop is $155. Fee includes instruction, adjustablebindings, ash wood frames, nylon lacing, and lunch — everything youneed to complete your very own pair of quality snowshoes withconfidence and ease. Registration and payment is due by Feb. 1 toensure that your kit arrives in time for the workshop.For more information, contact: Kathleen Ryan, environmentaleducation specialist, 833-0793 to register.
LEARN MORE
14hours
The period of a typical seiche across Lake Erie. For other lakes, theperiod is shorter, for example, in Lake Champlain in upstate New
York, it’s four hours; Scotland’s Loch Ness, about 30 minutes.
06/26/1954A seiche 2.44 meters (8 feet) high and 40 km (25 miles) wide hitChicago’s lakefront. Eight people were killed, most of whom were
swept into the water and drowned while fishing in Montrose Harbor.
1890The year the term seiche was first promoted by the Swiss hydrologist
François-Alphonse Forel who had observed the effect in LakeGeneva, Switzerland. The word originates in a Swiss French
dialect word that means “to sway back and forth.”
SOURCE: www.fact-archive.com/encyclopedia/Seiche
BY THE NUMBERS
CONTRIBUTED PHOTO
On Dec. 28, the power of waves fueled by steady winds broke up the ice dunes that were protecting the shoreline and created conditions for aseiche in Buffalo. Similar conditions on Jan. 30, 2008, caused high water level and waves of 12 to 16 feet, resulting in a record seiche thatcaused flooding in Buffalo.
Theword“seiche”(pronouncedsaysh) may have no meaning foryou.Butpeoplewhohaveexperi-enced the phenomena know thatit can cause death and destruc-tion in moments.
OneofthegreatestdisastersinBuffalo was caused by a seiche.It was produced by prolongedstrong winds pushing the watertoward that end of Lake Erie. Itoccurred at 11 p.m. on Oct. 18,1844,whenawallofwater22feethigh quickly inundated the com-mercial and residential districtsalong the waterfront. Withoutwarning, the water breached the14-foot sea wall and flooded thewaterfront.Seventy-eightpeopledrowned that day, according tonewspaper accounts. When thewinds stopped, the water movedback in the direction from whichit came.
Aseicheoccursinanenclosedbody of water such as a lake, bayor gulf. Like water sloshing backand forth in a bath tub, the waterin the lake is pushed by strongwinds and rapid changes in at-mospheric pressure, causing the
water level to rise on one side ofthelakeasitgoesdownontheop-positeside.Thewavessloshbackand forth between shores of thelake basin and with no warning,cause huge fluctuations wherethe shoreline and harbor waterlevels can rise or fall by manyfeet.
MostseichesgounnoticedandnevercausemuchdamageintheGreatLakesbecausetheyarerel-ativelysubtleandimperceptible,causing water levels on beachesto rise just a foot or less.
However,becauseLakeErieistheshallowestoftheGreatLakes,theeffectsofstorm-drivenwavesareamplifiedandwhenthewindblows from the southwest to thenortheast, seiches are more dra-matic.
Another record seiche in Buf-falo happened on Jan. 30, 2008.Sustainedstrongwindsfollowingthepassageofacoldfrontcausedthe Lake Erie water level to risesubstantially.Thehighwaterlev-els and waves of 12 to 16 feet re-sultedinerosionofthelakeshoreandsignificantfloodingattheex-treme eastern end of the lake.
Roads along the lake shorewerewater-coveredorclosedbe-
causeofspray.Floodwatersinun-dated the First Ward (west side)of the city of Buffalo, with entireneighborhoodsunderwater.TheLakeEriewaterlevelrose11feetaboveitseight-footfloodstageforover three hours. According tothe National Oceanic and Atmo-spheric Administration, this wasthe second highest lake level onrecord.
That same day in Erie, thesouthwest winds blew steady at35 mph and gusted up to 54 mphthroughout the day. As the waterwas pushed to the northeast, thehighwatercombinedwith12-footwaves and caused flooding onthe peninsula and lifted docksfrom their moorings. Harry Les-lie, park operations manager atPresque Isle State Park, said:“Presque Isle Bay filled up withfive to six feet of water from oneof the strongest storms I had wit-nessed since I started working atthe park in 1989.”
The power unleashed by thewaves and high water toppledicedunesthathadformedonthelakesideandbrokeuptheiceonthe bay, which had been dottedwith anglers before the storm.“Onedayyousawpeopleicefish-
ing; thenextdayyoucouldtakeaboat out,” Leslie said.
A similar storm occurred onDec. 28 after a record-high tem-perature of 67. The cold frontthatwhippedacrosstheareathatmorningbroughtdamagingwindsand created the right conditionsfor another seiche.
Winds, as high as 75 mph,wreaked havoc with the BuffaloBillsgameandresultedinpoweroutagestothousands.Threeduckhunters were rescued from theBarcelona Harbor when theirduck boats were swamped byhighwinds,rainandwaves.Asec-tion of Route 5 was closed nearHamburg, N.Y., but fortunatelythis time the water level in Buf-falo did not reach a record high.
The wicked winds that wreakhavoc and cause seiches whenthey whip across the waters ofLake Erie ended 2008 much asthey began — stirring up wavesthat rip out sections of beach,cause flooding and trigger dra-matic rescues.
A N N A M c C A R T N E Y ,Newspaper in Educationcoordinator, can be reached bye-mail.
Can you say ‘seiche?’Weather phenomenon creates dramatic effect on Lake Erie
By ANNA [email protected]
Lake Erie is the shallowest oftheGreatLakes,reachingamax-imum depth of 210 feet in theeastern basin. The axis of LakeErie runs from southwest tonortheast, corresponding to thedirection of prevailing winds.Lake topography combinedwith changing water levels andstrong waves can have extremeeffects on the shoreline.
Because of the lake’s shallow-nessandelongation,strongwindscanpushwatertowardoneendofLake Erie (setup), causing someof the most extreme lake setupsobserved in the world. A differ-ence in elevation of over 15 feetor more between the ends of thelake can occur. When the windstops, the water rebounds. Thisseicheeffectcancausethewatertomovebackandforthacrossthelake for some time.
When seiches of two feet orgreater are likely to occur, theNational Weather Service is-sues advisories for portions ofthe Great Lakes. These rises inwater levels can provide a baseon which high waves can attackthe upper part of a beach andpenetrate farther inland. Wind-inducedsurgesaccompaniedbywave action account for most ofthedamagetocoastalstructuresand beach areas.
The four factors that influ-ence the formation of wavescaused by wind and that deter-mine wave size are:
:7&)< 0+""<-:."2;%*/2%"<&028);"*#*+")
water that the wind has blownover.
:6&(" 2%" 4&)< %80 9'*4)over a given area.
:782"/ <"+2%-The greater each of the above
factors, the larger the waves.Waves are characterized by::783" %"&$%2 ,<&028);" #/*(
trough to crest).:783" '")$2% ,<&028);" #/*(
crest to crest).:5"/&*<,2&("&)2"/38'9"24"")
arrival of consecutive crests at astationary point).
:6%" <&/";2&*) *# 483" +/*+-agation or ways in which theytravel.
Waves in a given area typi-cally have a range of heights.For weather reporting and forscientific analysis of wind wavestatistics, their characteristicheight over a period of time isusually expressed as significantwave height. This figure repre-sents an average height of thehighestone-thirdofthewavesina given time period (usually inthe range from 20 minutes until12 hours), or in a specific waveor storm system.
Because the wave height var-ies, the largest individual wavesare likely to be about twice thereportedsignificantwaveheightfor a particular day or storm.
A N N A M c C A R T N E Y ,Newspaper in Educationcoordinator, can be reached bye-mail.
Wind-driven waves can damage shorelinesBy ANNA [email protected]
CONTRIBUTED PHOTO
Because Lake Erie is the shallowest of the Great Lakes, the effects ofstorm-driven waves are amplified. The high water levels and wavescause erosion of the lake shore and significant flooding.
Physical processes have a ma-jor impact on environmental,chemical, and biological pro-cesses and influence many oth-er types of user activities. Watersupply management, waste wa-termanagement,powerplantsit-ings, shipping, recreational andcommercialboatingandfishing,shoreline erosion and redistri-bution of sedimentary materialall rely on good forecasts.
NOAA’s Great Lakes Environ-mental Research Laboratory(GLERL) has a long history ofaddressing a wide range of en-vironmental issues in the GreatLakes and other coastal envi-ronments. GLERL is the onlyNOAA research laboratory thathas the breadth of scientific ex-pertisetoaddresscomplexGreatLakes ecosystem issues. GLERLresearch and programs provideimportant information to deci-sion-makers and others to helpthem make good choices.
All of GLERL’s long-range re-search is targeted toward pro-ducing a suite of forecasts andforecastingcapabilitiesofphysi-calandecologicalconditionsthatwilladvanceanecosystem-basedapproach to management.
TheGreatLakesCoastalFore-castSystem,theGLCFSWebsite,(www.glerl.noaa.gov/res/glcfs/)
is a useful forecasting systemfor all users of the Great Lakescoastalwaterswhorequirereal-time information and forecastsoftemperatures,currents,waterlevels, and waves.
These forecasts provide Na-tional Weather Service marineforecasters with a significantsource of information, whichshould lead to considerable im-provementsbothintheaccuracyand efficiency of marine fore-casts for the Great Lakes.
GLERL also has exceptionalresources for teachers to makeGreat Lakes data more acces-sible and easy to use with theirstudents.GreatLakesWaterDataSets for Teachers (http://people.emich.edu/srutherf/NOAA/)con-tains real data extracted fromon-going and historic GLERLresearch projects, includingtemperature, dissolved oxygenand seiche data.
Data is in a format that is easyto use in the classroom. Middleor high school students andteachers can conduct their owninquiries, support guided inqui-ries, demonstrate limnologicalconcepts or just practice graph-ing, mapping and mathematicsusing real data.
A N N A M c C A R T N E Y ,Newspaper in Educationcoordinator, can be reached bye-mail.
Where to find marineforecasts, data, more
CONTRIBUTED GRAPHIC
Wind set-up is a local rise in water caused by winds pushing waterto one side of the lake. An extreme form of oscillation known as aseiche occurs when there are rapid changes in winds and barometricpressure. This diagram is from www.epa.gov/glnpo/atlas/glat-ch3.html.
By ANNA [email protected]
Tuesday, January 13, 2009 | Erie Times-News | GoErie.com | 3D
