Содержание
- 2. Assessing the wildfire hazard in Canada
- 3. Drought Code (fuel flamma-bility)
- 4. Buildup Index = Fuel availability August normals
- 5. Fire Weather Index
- 6. Fire Weather Index August normals
- 7. Rate of spread (fuel, wind, topo-graphy) August normals
- 8. Head Fire Intensity = energy output (how hard is it to suppress?)
- 9. Critical factors in wildfire hazard in coniferous forests: 1. antecedent precipitation dry fuel canopy interception wet
- 10. Critical factors in wildfire hazard in coniferous forests: 2. humidity of atmosphere fuel dries out RH
- 11. BC fire history (1996-2006) Data: http://www.bcwildfire.ca/History/average.htm
- 12. Lightning fires 2003 British Columbia: 2003 fire season Fire Danger: 25 Aug. 2003
- 13. Fires in BC and adjacent areas, Aug. 22, 2003 WA ID MO Kelowna AB
- 14. OK Mountain Park Fire Discovered: August 16 August 25: 19,400 hectares Notes: The fire was started
- 15. Direct damage: homes ablaze in Kelowna suburbs Indirect damage: particulates and human health Smoke in Okanagan
- 16. Recent major fires in BC Lonesome Lake fire (S. Tweedsmuir Park) (2004): 20,900 ha burned Salmon
- 17. Fire management in BC Risk assessment: >200 weather stations reporting on fire hazard; Entire province covered
- 18. Fire bombers: water vs. retardant Okanagan Mtn. Fire (Aug. 22, 2003) Retardants (a mix of salt,
- 19. Southern California wildfires (October, 2003) Causes: Persistent drought Santa Ana winds Volative native and exotic vegetation
- 20. Wildfire hazards: Sydney, December 2001
- 21. Wildfire hazards (all photos taken from Sydney Morning Herald, Dec. 2001) 1. Damage to forest economies
- 22. Homes in fire-prone areas building a fire-resistant home, and developing “defensible space” around the house There
- 23. A defensible site Slope: Flames traveling up a 30% slope are commonly twice as high, and
- 24. A defensible house Roofs may be ignited by firebrands; use fire-resistant materials and remove debris from
- 25. Fire and slope stability El Niño La Niña La Niña normal (1997-8) (1998-9) (summer 1999*) (winter
- 26. Other weather-related hazards Frost hollows Fog Hail Cold spells Blizzards Freezing rain
- 27. Frost and fog hollows outgoing LW on calm, clear nights in late fall to early spring
- 28. Frost hollows as crop hazards: Okanogan County, WA. fan in orchard
- 29. Braking distances increase by a factor of ~10 on black (glare) ice data from California Highway
- 30. Advection fog ocean
- 31. Advection fog bank, southern Oregon
- 32. Fog formation by advection, Pacific Northwest coast
- 33. Fog incidence
- 34. Fog and road accidents Feb. 12, 1996: 12 killed, 100 injured in a 300-vehicle pile-up in
- 35. Fog and aircraft safety Fog can cause flight delays, cancellations, and accidents. Some airports (e.g. SFO)
- 36. Hail incidence (days/year) Note differences between this map and that of thunderstorm distribution (severe storms lecture)
- 37. Hail formation Feeder clouds Supercell anvil -10°C embryo ice pellets form -50°C all droplets are solid
- 38. Hail formation: feeder clouds and double-vortex thunderstorm -50°C -10°C 0°C supercooled water droplets embryo hail rain
- 39. Hailstorms, west Texas Flooding as a result of hailstorms e.g. “Isaac’s Storm”
- 40. Hailstones and hail damage
- 41. Hail damage Severe incidents Denver, COL -- US$625M insurance costs for damage from large hail (July
- 42. Hail suppression Based on the concept that there are insufficient ice nuclei in a cloud producing
- 43. Hail suppression logistics Seeding locations -- in vicinity of strongest updrafts; either at surface, in base,
- 44. Results of hail suppression N. Dakota: 45% reduction in hail insurance claims (1976-88) compared to a
- 45. Winter hazards Thermal: human discomfort and disease heating costs (10% of Swedish GNP!) damage to crops,
- 46. Frost hazards 180 d >6 months w/ frost
- 47. Hypothermia Cold exposure results in vascorestriction of blood vessels, restricting flow of blood to skin. When
- 48. Wind chill factor Until 2001, the Siple-Passel formula was used in North America to calculate wind
- 49. New wind chill equation In 2001 Environment Canada and the US National Weather Service adopted a
- 52. Winter hazards: property damage e.g. State Farm Insurance paid out $4M in house freeze-up claims for
- 53. Orographic Orographic Frontal
- 54. “Snow belts”
- 55. Blizzard hazards e.g. 1997 blizzard in southern BC (~60 cm of snow in 24 h in
- 56. Costs of snow - Surrey, BC
- 57. Snow-clearing costs I City Snowfall Roads Sidewalks Cost ($M) (cm) (km) (km) 1993 *costs $300K/cm of
- 58. Snow-clearing costs II Montreal has 72 ploughs, 47 loaders. 68 blowers (@$250K each), 100 sanding trucks,
- 59. Insurance costs In January 1993, a relatively snow-free month, 5200 auto insurance claims cost the insurance
- 60. Freezing rain Major ice storms in recent Canadian history: Montréal (1942) -- 39 mm in 2
- 61. The geography of the 1998 ice storm Up to 40mm in Maritimes
- 62. The 1998 ice storm: >1300 hydro towers and 40,000 hydro poles damaged
- 63. Ice storm climatology mT cA rain freezes on contact N S -20° 0° 20° -40° mT
- 64. The 1998 ice storm # of customers without power CANADA Qué: 1.4M Ont: 230K New Bruns:
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