NATURAL HAZARDS GEOG 3402
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Date Created: 10/29/15
Dimensions of Disasters Smith Ch 2 Dimensions of Disaster Topics What is a disaster How do we measure amp report disasters What are problems with our measuring amp reporting What are trends in disasters What causes these trends in disasters Disasters A disaster is the realization of a hazard typically meaning the more extreme realizations of a hazard that causes large fatalities and damages Smith though tells us that there is no agreed upon universal definition of disaster 80 Don t believe the numbers No agreed definition and poor records data really are educated estimates Why worry about disasters 15 million deaths over past 1000 years Due to 100000 natural disasters 80 of the deaths have resulted from four hazard typessee Table 21 p20 Earthquake Tropical cyclone Hurricane Flood Drought Measuring amp Reporting Who reports Governments may bias reports usually to downplay deaths maybe in certain regions Media attention to rapidonset emergency phase attention to large fatality rates abroad smaller events domestically Insurance companies becoming more involved with growing exposure and concerns What do they report Losses of life but rarely injuries Losses of property but only direct and immediate estimates Who keeps track CRED UN USAlDOFDA CU s NHRAIC all mentioned in text Measuring amp Reporting Problems with this system Disasters can be long duration impacts can be longlived show up years later and they are complex social events with pos and neg impacts Focus on fatalities belies injuries injuries certainly greater than fatalities factor of 2 or more Indirect losses and effects rarely accounted for See Disaster Impacts box 21 there are in every case Gaines and losses Direct and Indirect impacts Tangible and Intangible losses m a mum mun Wu J WWW mm m m Hummus nllunnn my Alfu u m w m MRImun mmmum V quotgym 4 u m Inquot my rm hm m a unlmuttumv 4 man awnm lhvmmvmh unmmmmrul mumnunuu mmmnlhxrmmh my wuwuw 1 wmmw r 1 Wm mm mm mm wwwmmn uhmymmmuummrmuvmmumm wm WW 1quot Mm Munquot wmmumm mm mm Wnyl mummy mm mm x M 0 MM m mm M mm m m m m k than Ihrkdimum mm W m mmw r m p WW w r mu m mm m ru n nunlvunlfm NIum IsmailM M mm m luau11 4 anquot m Imunnll k hm law an allcm um m H mm mm mm m w l Tangible Inlungible A L Physical 0 Loss oI Damage to g Business or Properly E Indusvriul 5 ProducIIon I h DIRECT INDIRECT v v Scenic Tourism 5 Building A Land egv l Wale homage s Disaster Characteristics and trends see fig 24 and 25 Atmospheric hazards are largest class of disastercausing natural hazards Earthquakes next Large death rates but less frequent disasterscale events Combined flood wind I EQ I droughtfamine are biggest killers globally Volcanoes and wildfires often reported seemingly frequent are less frequent and or less deadly overall So The Most hazardous geographies are floodplains coastal zones and earthquakes zones Overall disasters are increasing A Wim inw w a mm a 100 deaths 1 of GDP and 1 of population affected Increasing Disaster Rapid increase from first good counts in 1960s In 1970s and 1980s over 20 countries reported disasters that killed at least 10000 people Seven countries reported disasters that killed over 100000 eg Bangladesh storm surge Economic losses increasing too even in constant dollars nto years with 1005 losses in 2002 dollars WW 1 We39re now l mu 1975 low was WW wan moo Mp y m HM rm mlun Ammuul l mmWWW Mmmlvlh lurwmlmnvummmzmu Annua reported economic damages from natura disasters 19752006 g Em thth Fmvmu mm mm Japan mm mm w de mm mend Wu 1 USA Sm um Disaster Trends But Economic losses difficult to measure and difficult to compare over time Deaths not good measure for industrialized countries see Fig 211 Hurricane deaths in US declined while losses increased in constant dollars during 20th century will really go up after 2004 and 2005 seasons are added to data Do increasing losses reflect increasing vulnerability How would we answer this question Deaths per capita Loss per property investment at risk or maybe GDP gross domestic product It s difficult to assess whether trends is an increase per capita or per GDP 39timidiquotiquotihm39quoti Causes of Disaster Trends p 3235 Population growth occupancy of hazard zones Land pressure and degradation Urbanization Inequality vulnerability Climate change Political change less social supports in neo liberal era less development spending Economic growth Technical innovation Social expectations Global interdependence And in many situations risk of disaster is increasing for several reasons Eg The Worsening coastal storm hazard in US Developmentpopulation growth N Miami Beach condos ghD Land degradation Sea level rise loss of coastal wetlands and barrier beaches in La below and below right Risktaking Incentives like insurance and disaster relief to rebuild the same as before mum Bay 39 Calllou Buy I Let s go through the steps that yield hazard risk maps like these Shaking g Pga Peak Ground Acceleration Firm Rock I lt 10 1O 20 I 40 50 I 50 60 I 60 70 7O 80 he unit quot9quot is acceleration of gravity Hazard Assessment Monitoring data collection to determine magnitude frequency relationships thus probability Often extrapolate to higher magnitudes Some modeling and simulation may help especially for rare events few observations May also include historical and prehistoric reconstructions for more time depth old fault scarps of events centuries before Translate into hazard elements eg Eq mag M ground shaking g accel at some probability Not unlike effort to create a better historical hurricane data set Hazard Assessment cont Calculate damage loss curves Fig 55 orrefer to current engineering practice to choose standard event or risk threshold g with 10 chance in 50 years This standard risk allows you to create a map very important in EQ where local conditions affect ground motions but difficultrequires lots of field work geodata Map populations and property at risk Apply loss curves Go to Riskhazard Management NEVADA mum Fortunately seismology has provided lots of observations so frequencymagnitude relationships are getting well established esp modest event magnitudes The data pours in and over just ten years thousands of epicenters showwhere the eq action is in So Calif often but not always along surface expression offault the blue lines Aerial View of the San Andreas fault slicing through the carrizo Plain in the Temblor Range east of39the city of San Luis Obispo Photograph by Robert EWallaoe USGS x t 1 Fault scarps obvious 75 a 5 Geographical risk is also ascertained by mapping the faults some are obvious 39 ewe urmmmumz Aerial surveys right after eq s can reveal fault patterns not mapped before because they had no sfc expression Surface rupture 1992 Landers EQ San Bernardino County CA ranged from 2 inches to 20 ft Not all faults are created equal or offer equal risk some that are locked may not have ruptured in modern times but show prehistoric evidence of fewer big ruptures SO Different contributions to a point s risk of shaking by an ensemble of different faults EIPLA HATID N Fault BANNIMG F FAULT 3k Los Angeli 5m inclining 39 FAULT ii I I El Locked segment I I x Creeping segments ya 3 1 34 3039N 7 5 39 39quot 1 7 E J a I in 4 quot 39r 57quotquot E A a f V39 r W 39 I THE A quot1 I r a 72 p m quot quot 39 I 34 mm 7quot 0 1o 20 30 r 391 A 0 r A 119 new 118 30w 118 new Ground motions for known magnitudes and relationship bw ML and shaking can be established and then linked to frequency of seismic activity Here are peak velocity contours for the magnitude 67 1994 Northridge earthquake Contours of velocity are in cmsec measured by accelerometers Red star is epicenter note peak motions offset to north along foothills a NEVADA a CALIFORNIA E a A La tha AmzoNA a 5 Karsmw a m A Lumpu a S A xaw wl aggzagsusSag 5 a syo sgssw 555 x 3332 mmmmw Am Another step in risk assessment is to map actual damage here expressed by the Modi ed Mercalli eq intensity scale and link it to ground shaking and thus be able to project damage into the future MEXICO Add it all up Run lots of simulations Add new data all the time M and accelerations to let you know how each signature of a fault plays out across a varied topography Look for hidden quiescent old faults Match ground shaking probability left with pop idea of risk prob X consequence and you see a risk and low risk So Cal and Bay area are high risk Central Val ey even with significant pop is low risk Damage Projections You can also link ground motions to rough ideas or typically used as an anchor for such comparisons Box 51 in textbook lax s ms Momma MEREAUI Enmnum immsirv scm Away7w My mimuduwwiw n erimi i unity Maui mm aims mi amii anunp v aaisnimddinn iWim magma in swing Min mnmiiiigiiiy minim imam M iv My anymymmiimm im tin mm min i mm mm misting mi Naming mi smim iii m M iiim widi swig Win mi mimaiy v m m Wm WWW n zrvrkm uni imim i ummiiauiiimmii imamiai am Main immiiap mi m i immiimimi swimmii iizmuiiii vim u mm iim nmb whim w was Mimiam iium minim imiam iw w WNW iiiin iii imiiwiiiiai miy mm mm inwii aim mi mm iimui mu wind m m pawuiiw in Waiwaimiiixim was in mm iiwmiiiamwii winimims mi inmimii mm m mitimwmm WW Fuii Mm wiit my wwiimmimniium is Kim mi Wm Wain mii wnix magni ed Maintaing mumaniguuiiwumiidw a m Mm im mi chins W in mm ni aiiuiig Jim nimiiu i In um Mead Wm Gamma Miami Miami quotimam x 5m eiiimiimm WNW Mm anide iii minim widiiamagtieiimwm N W wait ipimi in mm in mini mi mm m m mm hudiyzmzted Rciigtxni quota mi mm m m Xi i7i W immi fawn mum am WM i Fm iiii w um 4iquot ii 5 W513i w m iii mi iimiigii mi wi mmmmvim do mm iiiw Viekywidxrwp uoiswm onzgmoAg Waggon u iiwisg Y E v m CURVE F1912 ms ANGELES l Excccd l war 1mg Earthsth I litm in 111 years E i d l l lime in muggy Exceedl l 1 time in lg years umvnll 39 lfamm39f m gxmmdmm p Exncdul timed 11mmch 1 gt y v 375 3 r r 4 39 2H 711 The map gives only one probability level but the statistical likelihood is continuous so you can plot probability for a place LA in this case and link mitigation to different levels of risk schools maybe built for larger motions with lower probabilities Final step in EQ hazard is mitigation Damage and Loss Reduction OK so you know the risk now you can you design and retrofit the built environment to reduce loss at least you start trying within limits of costs and benefits EQ Resistant DesignCode Global problem URM adobe brick stone Good weak structures like polethatch Good wood frame construction 80 houses in US Two main approaches in engineered structures Bracing and shockabsorbing bases strong flexible ductile materials eg steel framing allow motions to move thru the building w less damage Base Isolation is most extreme and expensive mitigation see next slide prevent motions form transmitting form ground to the building Base Isolation is very expensive so Maybe not every bldg but schools hospitals nuclear power plants dams etc Also gas water electric lines Avoid glass facades parapets balconies etc that fall away from structures often into streets on people Choose safer locations eg bedrock often better than clay alluvial sediments or manmade fill especially fill 7 P 7 Base isolation in Martin Luther King Jr civic center in Berkeley this was an expensive retrofit Does not work fortall bldgs Other approaches add bracing to transmit motions though bdlgs see next slide See more seismic design specs at th39IIwww whdn 39 39 39 desiqn QhQrresist hazards Bracing structural members that transmit waves thru the structure safel Can be tested on shaking tablesquot see htt 39 eerberke 7 It t ilwwwecscs EPFhtm Long Term Problem Still majority of structures even in EQ zones not resistant CA code improved in 1933 strengthened dramatically in 1970s and 1980s still most bldgs are at risk So there s a lot to accomplish in terms of emergency preparedness Especially since there s no skill in EQ predictions though it is known that catastrophic EQ events will eventually occur in American and other cities More on that later Tsunami Caused by earthquakes Large shallow focused E0 on sea bed Essentially seismic sea wave long wave length 100200km and low amplitude lt5M fast 5006000 Kmh Slow and build height near shore measured by height of wave trough to crest and run up zone or distance above normal high tide H and runup vary greatly along coastline shallowdeep bays vs points etc 157 during 19822002 So fairly frequent though often modest size Still quite deadly 5500 deaths during 19822002 2000 from one event Table 54 Perhaps 50000 deaths in 21St century then there was 2004 Tsunami Geographically most frequent in Pacific and Indian oceans JapanTaiwan Honshu 10 m wave R 10 yearsl 1933 event along Japan s Sanriku coast 24 m was r 70 yearskilled 3000 Alaska and US West Coast r F 39 i lndian oceanSE pacific Dec 26 2004 Sumatran EQtsunami killed some 186000 with 42000 missing or some 230000 httpiricolumbiaedulareeftsunamiTsunami Animation National Institute of httpenwikipediaorqwiki2004 Indian Ocea g n eanh uake H I r i x u 2 ml gt ml 54 V i hiquot 1 3 7 IV ar t39l u wr39i W 1quotquot an quot i ELThailancll u i 39 1 7 1 i39 i v I at a l t 1 39 397 quoti ll 39 v suiispiumgtl inr l 395 f i 9quot i 3 I39 i i all a Iquot 1i ls f l V iv 1 I l39 fit I r39 39I A C K39u I I 11quot in I 39 I II 399 Sn Lanka I i quotqz v I 1 1 I lb 1 i M v a Sumtar r x v 7 39 Lt Ell1r 391 hr 2 hrs 3 hrs 90 EQ 4th most powerful since 1900 Matched most deadly modern EQ 1976 Tangshan EQ in China Large area affected large height 4m and little warning even WI 2 hrs travel time to IndianSri Lanka C F u k 2004 Tsunami travel time hrs V r 7 Wave Ha hi cm L1 A 7 J I 2 4 b a m an 33 EDI lquot 1333 Warning System Pacific only Tsunami Warninq I Watch Advisory Warnings issued by the National Weather Service39s tsunami warning centers Actions ba locate and size major earthquakes in the Pacific asnn b determine their tsunamigenic potential c predict tsunami wave arrival times and when possible runup on the coast and d provide timely and effective tsunami information and warnings to the population of the Pacific to reduce the hazards of tsunamis especially to human life New systems going in Atlantric ocean and Indian ocean 6 vi 4 sasmogmphs c Tide stations aska Aleulh Selsml Zane nvironmmai lahnmmry PMII dEVEIODEII We fim meanbased and Repeni g uf Tsunamisquot UAW mes a HIPSSUIP gauge anrhmcd m me see New When a tsunami passes Srienlistn 1 III Mammal Omani and Auwspherk Adminisllation analyie signals and deude il a Bunami Naming is necessary i K L a ADARIslah v A I wen Eonsr is mami Wamlng MEI PalmerAIaslva Paci c Ocean VSMBIN Waning geng Em lend Hawaii ourte NCAA DMEL DART cquot A and Remaran of 1sunamis Ihe huuy asur Ilansmined m a sateIQitE caskauli Subducn or l 0 Zone 5F Recurdm sinus dam Anthurchan v n quotv u 1 a w V d a gsgS a We LINE 93a h om pl 5an level vecmder an the team IDaI measures mange in MM pingsqu 35 a tsunami m M 39 vases overhead M39VHF J MN39I HIM H1 Predicting magnitude is challenge height and runuplinundation Scenario 1 Scenario 2 Sce ar io 3 Sce ar i L 019361 El 39D Em httpwww pmel noaaqovtsunam ipuqetsoundpreZImovieps html Preparedness Tsunami inundation and evacuation maps glow avaiIabJe for West Coast 1 t g TSUNAMI HAZARD ZONE IN CASE OF EARTHQUAKE 3930 TO HIGH GROUND CIR INLAND I JJ EVACUATION ROUTE SHELTER Tsunami preparedness along US Pacific coasts I auz I auz I muE auwrmwr rum in mi Tsunameters the Deepocean Assessment and Reporting of Tsunami DART program sensors Chap 8 Severe Storms Tropical Cyclones Hurricanes We start severe storms and focus on tropical cyclones aka hurricanes Tropical cyclone hurricane typhoon Wind rain flooding and storm surge and embedded tornadoes About 15 of global population is threatened Perhaps 6000year fatalities about 60K during 199201 10b annual damages 1995 dollars Large and growing exposure and vulnerability in US Caribbean 8 and SE Asia Australia I It Themes Measuring monitoring warning evacuation systems Hurricane risk assessment Physical protection amp ways to decide how to deploy protection Building and land use mitigation 014w per year W29 pel year a 30 and mare per year 4 Average Tracks Y jgmeg j Wnrld 39 39 quot 39 Thss emphasises e 39 Nnrrh n y 39 eaten pupulated mm areal mum Aim Berz 1990 Physical Cause Tropical lows form over 26 C 82F ocean surfaces often in ITCZ If conditions are right the rising warm air over lowlatitude solarwarmed waters sets off a positivefeedback Ascent causes convergence Condensation release of latent heat causes increased buoyancy thus Increased ascent and Increased convergence Area of convergence enlarges more water vapor to draw on Causes Spin imparted by Corriolis Force increases convergence ascent and buoyancy so winds speed up Centrifugal and centripetal forces come into balance also creating the infamous eye wall Input and output balance low level inflow to low pressure upper level outflow from high pressure and storm can reach a steadystate Decay Loss of energy water vapor loss of upper air divergence friction of land All these can weaken it by upsetting the balance of forces Winds weaken with height and air spirals outward clockwise at high altitudes 7 Maximum wind found in gygyrallat Surface The mature storm is drawing in warm moist air from a large area into the tightening counterclockwise spiral then up in the wall cloud and out with upper level divergence and clockwise outflow The eye is distinct as the one area of concentrated sinking air in the system sinking warms and dries the air thus eye is often clear Like a spinning skater the fastest spin winds are right near the center where the angular distance they must travel to circulate around the low are shortest How Intensity is Measured Wind speed 33 ms 74 mph arbitrary threshold Central pressure commonly 2800 in or less 30 is normal sea level pressure Storm surge height 18 m 320 ft above mean or high tide Also Wave heights total rainfall and rainfall rates inland flood heights Saffir Maximum sustained wind Minimum surface St orm surge Simpson speed pressure Category mih ms kt mb ft m 1 7495 3342 6482 greater than 980 35 110739 2 961 1 0 4349 8395 979965 58 125 3 1 1 1130 5058 961 13 964945 912 4 131155 5969 114135 944920 1318 S s9639 5 156 70 136 less than 920 19 57 The 88 scale puts all the magnitude measures together into five categories a practice common in many hazards now from earthquakes to snowstorms but one that does give up some detail and specificity of magnitude Visible satellite image spiral bands of convection wall cloud around somewhat cloudy eye plus outflow cirrus clouds How Monitored Tracked and Forecast infrared satellite image shows cloud top temperatures higher are colder colored red higher clouds is sign of stronger storm Outflow cirrus especially vis to north How Monitored Tracked and Forecast HURRICANE ANDREW NWS MIAMI RADAR August 24 1992 0835 UTC 0435 EDT Hurricane Research Division M NOAAAOML A i 39 r Dmmin me mom a A 4 1 dadar bounces off of precipitation which is most In ense in eyewall and feeder spiral bands dBZ is measure of radar beam re ectan e saw mil 4 mum Mom Katrina s eye wall from Hurricane recon aircraft NCAR GPS Dropsonde the definitive atmospheric pro ling tool Vents riii cnute witnin 39 in secdnds arter reiease Squarecone Parachute mm mm increases stapiiity er dppsende Shack cord reduces stress wnen cnute epens microprocessor ceriireis tne transmitter and digitizes data rrem tne sensers I 951 cps Recelver ceiiectstne data rrem GPS sateiiitesused tn caicuiate Wind speed and directien p1gAVar Batten pack preVides pduerrer atieast dne neur Pressure sensor Ram Transmitter sends temperature humidity pressure and GPS Wind data tn tne aircrart evenu 5 secends 4 a4 Humldl sensors andtemperamresensor Sande tengrrr Demer er 275 Fall Speed ranges rpm 36 mpn WSW DEEibs atQEI EIEIEIfEELtu 24 mpn atseaievei A drep rrem mum reet iasts 7 minutes Risk Assessment Exposure Hazardous geographies lowlying densely population coastal areas Bangladesh low gradient deltaic area with little refuge subject to cyclones in Bay of Bengal only about 5year 1970 300K deaths 75 million due mostly to storm surge 39 m 1991 another strike this time 139K deaths in 6 m surge Cyclone Sidr Nov 2007 Approx 10000 fatalities P w r mmmrvsWswmaerwumum39yw Mngwmmmmm mman 24 mmmmmw swam WEEK wwwme mm mm gummmmmwmm A 0 77 v L m L F s AVN39G LVA D39IE s H J lt Tr uenms rmmmm mm mun lumen m mamas wuhha mm 0w 3 cm INDIA quotquot74 i WM 1 m am am Mmm mnuarm We 5M m1 mwmnmn y mmqu 14 5 m w tnhmme rv am w 5 4mm a u in mm a so Wm Mmmmmm BURMA Hazardous geographies Islands Philippines Taiwan smaller Pacific and Hawaiian islands Caribbean Islands Urbanized coasts of large land masses Atlantic and Gulf of USA China Japan Australia lm pacts Main damage causes are Storm Surge 39 1900 a killer here and still the most lethal part of hurricanes Katrina surge near 1 Gulfport MS Not many photos of storm surge as difficult for storm chasers to stay in front of it of the effects of storm surge Hurricane Camille 1969 Gulfport MS Hurricane Camille 1969 Gulfport MS And plenty of developed coastline at risk from ompano Context Hazards Chap 13 Chronic and Soil erosion waterlogging salinization Pest resistance Ground subsidence Wetland degradation Climate variability seasonal and multiyear swings in temp and precip eg El Nino droughts floods disease etc Focus on Global warming Changes in precip amount timing intensity Temp Variability extreme events Floods droughts Disease Severe weather thunderstorms and hurricanes Sea level rise Global and Herrispheric Annual Terrperalure Anomaiis Instrumental records of 13564005 show warming overtime Norihem Hemisphere 39remperaiure Anomaly quot0 Hemisphere 1am I we 940 Ban 1990 moo Source I in anes I J ceborn md K a Brine Unlvewt oi East An he Norwid1 UK a E Per er Mel algae Breekneil Berkshire UK As Greenhouse Gas GHG concentrations increase the net energy in the system increases due to trapped outgoing radiation and the earth will warm even more The unknowns especially are a future concentrations of GHG due to industry economy population technology etc and b how sensitive the earths system is to the increased energy the uncertain balance between positive and negative feedbacks 6 I I I I l I I I l Scenanos A1 B 5 A1T These scenarios are all A1F different projections of A2 population technology 4 B1 amount of fossil fuel use Bz S92a energy consumption etc The GHG concentrations are then run thru global climate models and they also give different results for a given GHG concentration so there is uncertainty both among the scenarios and within the scenarios They 0 I I I I all yield a net warming 2000 2020 2040 2060 2080 2100 however Years l892a TAR method N Temperature change C 0 IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII So the best science still only gives a wide range of likely warming rates Temperaitu rev change FEE 42 Tmparema Ema age j 39 m 4 230 1 arm garlic M m glee Elem But even the lower projections of warming put us in temperature Vaunnonsot llmEarlhswacc lcnmlalum vcars iuouzr2mo territory unlike any in the kuvnmmwwn awn qu past several centuries quotquot quot quot W39 3335 Most analyses make them Earth by 2100 the as 39 warmest it has been in V since the last ice age as m ach impact area has further uncertainty Here isthe scienti c uncertainty for sea level rise which 39 r 39 r t simply a 39 39 39 quot 39 ocean expands But how much ice is there to melt and how fast will it melt May increased precipitation in a warmer world counteract some ofthis melting Also the socio economic effects of a given sea level rise are uncertainty will we build levees E EL nl o o E 1 nl Zlt Sea level use in of Bangladesh n l l i i i i l n 2000 2010 202a 2030 2m 2050 20m 2070 2m 2090 2 a Vezr Global warming changes the distribution of climate variables lIke temp or precip recall this illustration from Chap 3 The shape ofthe distribution means that extreme events can increase dramatically with relatively small changes in mea m mumw m ilu mum wluc wuh umsmu wi39ir atlgimldiuriwrinn mamme Milly n5 cxp u mm al in m r 1 mi i W m t it h mm 5 l xlu Llucshulnl rises mm m llulLl KL oi Iuw39 m rKrrvmc mm Tim mm mum in mm 39vnl 1 WWW WWW 39 W mum awnMW 011M pmbmhrv inncuom lmmnu exirrmely m M mm H MW mu WWW ml man mayquot yquot MM v I lugh wmnml Muhammad i uugwl Diwhmiuvi 2 4mm l i ll 2 g r Tg l H i i NM w Wquot M i i if y r 7 7 m m n n m m m l twwu mm mm Mugnimdh These culverts in Boulder which some of you observed in the oodplain scavenger hunt should pass the 500 year runoff They may be able to absorb lots of climate change before failures become noticeably too frequent But as soon as they absorb any change that worsens ooding they no longer meet their explicit design standards Solution rebuild them or change the performance standard eg we can live with conveying the 400 year event after all There is also much concern over global warming impacts peraps worsening hurricanes droughtsheat waves Multiple Cat 5 hurricanes like Wilma above marked the remarkably active 2004 season but National Hurricane Center forecasters argued this was not an effect of climate change Climate Change Also Alters the Frequency of More Common Events 3 Annual Frequency of 110 Degree Days by Decade at Phoenix AZ 18905 19005 19105 19205 19305 19405 19505 19505 19705 19805 19905 20005 The Current State of Global Warming Science Reports from the Intergovernmental panel on Climate Change IPCC in 2007 months tell use the latest science and latest thinking about impacts on natural and social systems httpvvwwipccch lNTERGOVERNMENTAL PANEL ON CLIMATE CHANGE gig Climate Change 2007 Impacts Adaptation and Vulnerability Working Group ll Contribution to the Intergovernmental Panel on Climate Change Fourth Assessment Report Summary for Policymakers This Summary for Policymakers was formally approved at the 5 quot Session ofWarking Group ll at the lPCC Brussels April 2007 OHS made as of IS April 2007 Correcu Note iext able and gures given nere are nal bulsumecttu checking and copye editing and editorial ailiustmenzs in gures Impacts From the IPCC Depending on where the earth is on the range of potential future temperatures the impacts could be modest or severe Climate Effects Overall Surface Warming Increased precip overall but drier in places Warmer high latitudes Drier midlatitude continental summers Rising sea level Impacts agriculture especially low atitudes maybe net positive then negative impacts on yieldproduction Water resources mostly negative with potential for both more floods intense rain events and droughts exacerbated by warmer temp and thus higher ET Ecosystems significant loss of species shifting and degradation of many ecosystems like tundra reefs grasslands Negative health effects eg spreading malaria more heat waves Natural hazards worsening severe storms and hurricanes plus sea levels means worse storm surges Finish Chap 4 PreparednessNVarnings and Land Use PreparednessNVarnings Community emergency plansdrills Warning Systems three types of forecast Predictions statistical likelihood Forecasts timing location magnitude with some lead time Warnings specific message of impending impacts and response Hurricane Flood Protection modify the event Earthquake Tsunami wildfire u Magnitude duration extent Natural Events System I Natural Hazard Impacts H Response Deaths injuries Human use economic loss System Populations A Reduce loss burden Agriculture Settlement Adapt reduce human Disaster aid Transportation vulnerabiilty warning systems insurance land use regulations etc Housing Warnings Systems Fig 410 Four Steps in a warning System Threat recoqnition preliminary setup Hazard evaluation monitor assess decide on warning Warninq Dissemination getting it out Public response correct behavior Timing Acquisition Content interpretation woszmzo ltltm36 9amp53 Forecast amp Warning Systems Physical and Social Science issues Physical Accuracy timing location magnitude Lead time inverse with accuracy Specificity varies with lead time All these differ for different natural events Lead Times Spatial Scale Riverine floods weeks to days whole river basins Hurricanes days to hours 1001000 mi coastline Blizzards days to hours states Flash floods hours to minutes small streams Tornadoes minutes1 hour counties and communities When and here m Aalur nmvctwlmorDEN SwaLPnquot mmsmumm unmua mmmmms mnnucm mmm mum 037w y m M 115vsn mm When and Where with Social Issues with Warning Systems Target Audience handicapped language class culture Confirmatory behavior Response to content delivery source Previous experience of the hazard and hazard awareness FWS Warning systems needs both FORECAST elements accuracy lead time specificity and RECOMMENDED NEEDED ACTION elements Required response has its own time frame Coastal Evacuation hurricane 12 days Quick move away from streams flash flood or ocean shore tsunami minutes to hours Take cover minutes even seconds Combination of Forecast ability and Response ability dictate FWS structureinstruments Warning Dissemination Hurricane Warning radio TV police patrols TornadoFlash Flood sirens reverse 911 maybe police patrols Other Hazard WFS Little or no skill a Earthquake a Valcam Landslide Avalanche Rockfall Pa ific 0 ean Tsunami WarninngSySte m is easily estimated allows for some warning though forecasters can39t say what the wave will do when it gets to the coast each coastal section responds differently GEOWARN mm mm a mum mmmnm immmfngm w mummy cm nunnememv mmquot ummw Evcurllan Marni1E Early warning system managingmm 7 Hmmmhmwmm uni mmmunicl u n mu Maniquot Implemenlatmn to cvwll comi m cllu Drl 39 quot9 civil defame quotquoti39l39 zlli 39 39ai sm E5hmaiion of ammui i i li i m activity index v ymmnamico msu quotmm murmurquot m m mummy Mm an wlrnln lnn Velluw cmlvmun 3w Liam m N Rating of correlations u m mmmmw mmw ulillllutmnulur mm 7 mquot in mmquot Correla n analysis of precursors mm mum Nahumml mum mummnmwmm i mm Mumpimcmmim fmicmm WNWmm mum mammal mm m M w m g m nskln nan mm a Damnlmlcnnn Rwlana wayn lg y qu vieaphymlwlwmeruumn Volcanologists are developing a warning ranked system for volcanic eruptions is applied casebycase Other FWS issues Fear of overwarning and warning fatigue underwarning Tiered warnings with lead timeaccuracy problems Ambiguous warnings a problem Mt Ste Helens ashfall example Preplanning preparedness awareness programs crucial to warning success Land Use Long Term Mitigation Use land planning and regulation to mitigate exposure to hazards Macrozonation regional plans can include hazard assessment and general guidelines for hazard mitigation but details are in Microzonation Zoning ordinances detail what can be built where and how can include hazard requirements Overlay zones detailed hazard mitigation added to standard zoning seismic siting and design for small areas EQ Zoning Example AlquistPriolo zone in Calif restricted building sites see Box 43 for details LU as mitigation Floodplain zoning insurance limits on new building retrofit Earthquake zoning req seismic building codes special features for critical facilities eg schools and hospitals gas lines Tools Regulation subdivision regulations require mitigation Public acquisition of hazard land keep development out Problems with land use approach in US Private property rights antiregulation a udes Land use case law finds some restrictions unconstitutional takings Lucas vs South Carolina property owner sued state over beachfront set back after Hurricane Hugo he won Limited scientific guidelines for LU eg where will groundmotions amplify Flood Hazard Reduction Flood plain regulation Insurance w mitigation Protection Warning systems Flood Hazard Mitigation Floodplain mitigation Floodproo ng bldgs raiseelevate water proof relocate utilities property etc Relocation out of oodplain Insurance w mitigaiton federal state and local Ex eut or design rim Examples of mitigation in the oodplain Fig 1012 in textbook 104 in textbook based on 100 year oodplain Requires insurance for a mortgage subsidized and market and local regulations requiring mitigation and preventing lloodway encroachment Floodway is area that development raises llood level Problems dif culty de ning FP Local regs not always in place repetitive loss low market penetration low risk perception many w o mortgages so insurance not required by banks limo year oodplamT aodwa 7 r v Flood Protection Physical Structural Dams levees walls berms levees most common extensive Oversize everything reduce obstacles in FP widen bridges Prevent debris damming Flood and stormwater conveyance and retention structures Big reservoirs like Shasta and Oroville in Calif are multi purpose water supply recreation and flood control but must maintain empty capacity to absorb floods when filled they spill excess through a spillway right I iEufll39lill Mm PulpL71 l39ltnquotI39Il39rl tgt39l 45 j 450 JSLEHL39I Furi H H i 440 I H J FMAMJJASOND WE figure 1 P l ri illlli Ruin Hunt 111 Skunkuniultuck Helm Reservoirs used for flood control must be kept below maximum level during the flood season in order to be able to absorb high runoff This one in Oregon is held low to absorb wintertime rains and snowmelt common in the Cascade Mts Reduciion in flood peak below the darn Reservoir gt o 9 lnflow 39 E Hood 3 4 Reservoir 5 Outflow g spill 39n39 Time Fig 1010 from text shows idealized effect of a reservoir in which flood inflows are held and released over time to lower the peak Area under curves is the same Levees are everywhere in So Florida to control oods and along the Mississippi the Sacramento valey in Cal and many other oodplains Fiaml cnnlml sluicture on Lake Okeeclwl This levee shows the control structure that allows oodwaters through right side at a controlled rate and pumps le side that can send water back in this case back into Lake Okeechobee FL that o en oods with heavy rains and in hurricanes New levees built along the Red River in Grand Forks N after a devastating ood in 1997 cause over 800m damages This section is a removable gate that allows access to open space on the oo plain and can be closed upon aflood warning 39 Retention ponds are everywhere and are standard in almost any new development in quot qthe West Vegas freshly dug left and a parklike retention pond in Salt Lake City You can nd many examples of ood mitigation along local creeks and rivers In fact Exercise Three asks you to visit the oodplain and look nd and identify such protections on Boulder Creek see exercises page of class website Here are some examples along a Colorado stream W a A ood wall protecting a key facility in this case a justice centerquot including courts police and emergency of ces puin m An cn394a 5n39 n ma u um 5354quot That flood wall can be seen on Google earth Jim Oversized culverts and raised elevated buildings just a few feet in this case Halyes Huuga 195 s m Flood damage led owners to build a berm to keep out future high water an offer room for bikepad path and wildlife to pass but do cost a lot more mall 39 quotquot l 39 reduce erosion Sized for a major ood maybe 1 in 500 years Stormwater and oodwater retention ponds identifiable because they have spillways or inlets and maybe outlets not visible in this phoot me pillway39 39 39 39 39 lowered stretch ofthe bikepath right where the bicyclist is Exercise 3 Hunt for Mitigation Boulder Creek Floodplain see class website Floodplain features road bridge structure numerous but be sure to ID and describe how mitigated pedestrian bridge structure numerous especially II and II describe how mitigated raised building I and IV flood wall I protective berms III and others flood water spillway and retention pond V building relocation in this case public acquisition and removal now open space ll bad examples of public buildings in floodplain I II III and V you can find others warning sirens I and IV Floodplain Segments I mouth of canyon to Broadway ll Broadway to 17th Ill 17th to 28th IV 28th to Foothills parkway V Foothills to 55th Questions 1 Prepare a list of five floodplain features from the categories above one from each except you ma use two bad examples if you wish with a detailed location and description of howthey reflect the flood hazard using concepts and terms from class 2 For ONE of your features write a brief one paragraph 100 word critical assessment of its risk or mitigation addressing Why might the mitigation not work Why is the use inappropriate for a floodplain
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