The large fires that shape western Washington. Josh Halofsky and Daniel Donato Washington State Department of Natural Resources December 2018

Transcription

1 The large fires that shape western Washington Josh Halofsky and Daniel Donato Washington State Department of Natural Resources December 2018

2 How much old-growth was there in the past? A simple question

3 Wanna know about old-growth in western WA?

4 Wanna know about old-growth in western WA? Gotta know about fire

5 Some context Wildfires between

6 -Van Pelt 2007 Some context Wildfires between

7 -Van Pelt 2007 Some context Wildfires between

8 Some context Wildfires between

9 Characteristic fire (historical) Infrequent high severity Moderately frequent mixed severity Frequent mixed severity Very frequent low severity Spies et al. 2018

10 Life & times of a Doug-fir/hemlock forest ~ years Van Pelt (2007)

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15 Eagle Creek Fire 2017

16 How big were the largest fire episodes?

17 How big were the largest fire episodes? ~6 million acres

18 How big were the largest fire episodes? 1,730,000 3,500,000 4,700, ,000 1,700,000 2,200, ,000 1,200,000 1,500,000 ~6 million acres

19 Not the first to suggest this Year ~1700 fire episode: >1 million acres on Olympic Peninsula, 3 to 10 million acres in western Washington - Henderson et al. 1989

20 Not the first to suggest this Year ~1700 fire episode: >1 million acres on Olympic Peninsula, 3 to 10 million acres in western Washington - Henderson et al Yacolt complex >1 million acres - Natl. Int. Fire Center [nifc.gov] Tillamook burn 350,000 acres - Kemp et atl 1960

21 Early land surveys Spies et al (summarizing Plummer 1902, etc.)

22 Early land surveys Spies et al (summarizing Plummer 1902, etc.)

23 Early land surveys Spies et al (summarizing Plummer 1902, etc.)

24 The M.O. of large westside fires Three factors coincide: 1) 2) 3)

25 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) 3)

26 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3)

27 Causes of western Washington fires Human Lightning -DNR Wildfire Division

28 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event

29 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours

30 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours Tillamook Burn: Yacolt Complex: 200,000 acres in 24 hrs 30 miles in 36 hrs

31 Large fires couldn t happen today, right? Fire suppression? Modern infrastructure? Fuels management?

32 Large fires couldn t happen today, right?

33 The M.O. of large westside fires Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours Tillamook Burn: Yacolt Complex: 200,000 acres in 24 hrs 30 miles in 36 hrs

34 Large fires couldn t happen today, right? Fire suppression? During wind event, a non-factor Modern infrastructure? Fuels management?

35 Large fires couldn t happen today, right?

36 Large fires couldn t happen today, right?

37 Large fires couldn t happen today, right? Fire suppression? Modern infrastructure? During wind event, a non-factor Largest events burn through Fuels management?

38 Large fires couldn t happen today, right? Fire suppression? Modern infrastructure? During wind event, a non-factor Largest events burn through Fuels management?

39 Large fires couldn t happen today, right? Fire suppression? Modern infrastructure? During wind event, a non-factor Largest events burn through Fuels management?

40 Large fires couldn t happen today, right? Fire suppression? Modern infrastructure? Fuels management? During wind event, a non-factor Largest events burn through Less relevant on west side

41 The future: Climate change

42 The future: Climate change Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours

43 The future: Climate change Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours

44 Causes of western Washington fires Human Lightning Population increase of ~2.5 million between across Washington -WA State Office of Financial Management, DNR Wildfire Division

45 The future: Climate change Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event hours

46 The future: Climate change Three factors coincide: 1) Dry, late summer conditions 2) Ignition source 3) Synoptic east wind event? hours

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48 Big events are part of the system Built-in resilience!

49 Cascadia Subduction Zone

50 Cascadia Subduction Fires

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54 DRM; oregonhikers.org Thanks!

55 Not a fuel-limited system