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LESSONS LEARNED FROM PAST NOTABLE DISASTERS NEW ZEALAND PART 2: WINDSTORMS AND TORNADOES . Walter Hays, Global Alliance for Disaster Reduction, Vienna, Virginia, USA . Natural Phenomena that Cause Disasters. Planet Earth’s Seasonal Atmospheric Interactions Can Cause Tornadoes.
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LESSONS LEARNED FROM PAST NOTABLE DISASTERSNEW ZEALANDPART 2: WINDSTORMS AND TORNADOES Walter Hays, Global Alliance for Disaster Reduction, Vienna, Virginia, USA
Natural Phenomena that Cause Disasters Planet Earth’s Seasonal Atmospheric Interactions Can Cause Tornadoes
NATURAL HAZARDS THAT HAVE CAUSED DISASTERS IN NEW ZEALAND FLOODS GOAL: PROTECT PEOPLE AND COMMUNITIES WIND STORMS AND TORNADOES EARTHQUAKES HIGH BENEFIT/COST PROGRAMS FOR BECOMING DISASTER RESILIENT VOLCANOES ENVIRONMENTAL CHANGE GLOBAL CLIMATE CHANGE
WELLINGTON • Wellington is renowned for its winds and windstorms. • The wind-funnelling effect of Cook Strait and the rugged topography lead to FREQUENT, strong, and highly variable wind fields and storms around the southern coast.
PAST SEVERE WINDSTORMS • Wind records from Cape Palliser and Castlepoint show that maximum wind speeds of up to 200 kph at Kelburn occurred during the Wahine storm on April 10, 1968, and 215 kph at Hau Nui during the October 19, 1998 Wairarapa storm
BAD NEWS 2-WEEKS AFTER THE DEVASTATING CHRISTCHURCH EARTHQUAKE A SEVERE WINDSTORM “THE SIZE OF AUSTRALIA” IS ON ITS WAY
Gale-force winds of up to 130 kph, accompanied by heavy rain, lightning and plunging temperatures, impacted the capital, Wellington
IMPACTS: The power was out, trees and sheds were on fire after more than 100 lightning strikes in the Hutt Valley and Kapiti Coast.
New Zealand experiences, on average, about 20 damaging tornado events each year, which are typically very narrow with short tracks and in the F0 to F2 range.
Most tornadoes in New Zealand have occurred in the North Island, particularly around the Bay of Plenty and down to Auckland
Another concentration of tornadic activity is on the western coast of Taranaki near New Plymouth
NEW ZEALAND’S WORST TORNADO • New Zealand's worst tornado struck the community of Frankton then moved into neighboring Hamilton on August 25, 1948.
IMPACTS OF NEW ZEALAND’S WORST TORNADO • The twister, rated as F2, killed 3, injured 80, and damaged or destroyed 163 buildings and 50 businesses.
IMPACTS OF NEW ZEALAND’S WORST TORNADO • The winds lifted buildings, snapped off chimneys, pealed roofs off houses, and uprooted trees. • The air was filled with flying corrugated iron, branches of trees, timber and kinds of debris.
HAZARDS EXPOSURE VULNERABILITY LOCATION ELEMENTS OF TORNADO RISK RISK
A DISASTER CAN HAPPENWHEN THE POTENTIAL DISASTER AGENTS OF A TORNADO INTERACT WITH THE VULNERABLE BUILT ENVIRONMENTS OF NEW ZEALAND’S COMMUNITIES
TORNADO HAZARDS:HIGH VELOCITY WIND FIELDand FLYING DEBRIS ARE POTENTIAL DISASTER AGENTS
CAUSES OF DAMAGE WIND PENETRATING BUILDING ENVELOPE UPLIFT OF ROOF SYSTEM FLYING DEBRIS UPROOTED TREES TORNADOES IRREGULARITIES IN ELEVATION AND PLAN “DISASTER LABORATORIES” SITING PROBLEMS UNANCHORED CONTENTS
A DISASTER is --- --- the set of failures that overwhelm the capability of a community torespond without external help when three continuums: 1) people, 2) community (i.e., a set of habitats, livelihoods, and social constructs), and 3) complex events (e.g., tornadoes, earthquakes,..) intersect at a point in space and time.
Disasters are caused by single- or multiple-event natural hazards that, (for various reasons), cause extreme levels of mortality, morbidity, homelessness, joblessness, economic losses, or environmental impacts.
THE REASONS ARE . . . • When it does happen, the functions of the community’s buildings and infrastructure will be LOST because they are UNPROTECTED with the appropriate codes and standards.
THE REASONS ARE . . . • The community is UN-PREPARED for what will likely happen, not to mention the low-probability of occurrence—high-probability of adverse consequences event.
THE REASONS ARE . . . • The community has NODISASTER PLANNING SCENARIO or WARNING SYSTEM in place as a strategic framework for concerted local, national, regional, and international countermeasures.
THE REASONS ARE . . . • The community LACKS THE CAPACITY TO RESPOND in a timely manner to the full spectrum of expected and unexpected emergency situations.
THE REASONS ARE . . . • The community is INEFFICIENT during recovery and reconstruction because it HAS NOT LEARNED from either the current experience or the cumulative prior experiences.
NEW ZEALAND’S NEXT STORM OR TORNADO IS INEVITABLE • ---SO, DON’T WAIT TO BE REMINDED ONCE AGAIN OF THE IMPORTANCE OF BECOMING WINDSTORM DISASTER RESILIENT.
THE ALTERNATIVE TO A STORM OR TORNADO DISASTERISWINDSTORM DISASTER RESILIENCE
WINDSTORM HAZARDS • INVENTORY • VULNERABILITY • LOCATION • PREPAREDNESS • PROTECTION • FORECASTS/SCENARIOS • EMERGENCY RESPONSE • RECOVERY and • RECONSTRUCTION WINDSTORM RISK POLICY OPTIONS ACCEPTABLE RISK RISK UNACCEPTABLE RISK WINDSTORM DISASTER RESILIENCE DATA BASES AND INFORMATION New Zealand’s COMMUNITIES HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS
LESSONS LEARNED ABOUT DISASTER RESILIENCE ALL TORNADOES PREPAREDNESS FOR THE LIKELY DAMAGE IS ESSENTIAL FOR DISASTER RESILIENCE
LESSONS LEARNED ABOUT DISASTER RESILIENCE ALL TORNADOES WIND ENG-INEERING FOR BUILDINGS IS ESSENTIAL FOR DISASTER RESILIENCE
LESSONS LEARNED ABOUT DISASTER RESILIENCE ALL TORNADOES TIMELY WARNING AND PERSONAL PREPAREDNESS IS ESSENTIAL FOR DISASTER RESILIENCE