Climate change, permafrost and water in the NWT. Steve Kokelj INAC

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1 Climate change, permafrost and water in the NWT Steve Kokelj INAC

2 Indian and Northern Affairs Canada Steve Kokelj

3 Outline Permafrost and climate change Climate change impacts in the NWT Case study climate change, land and water

4 Permafrost

5 Permafrost is a defining feature of high latitudes ACIA

6 Permafrost thickness S. Wolfe

7 Ground temperature Temperature ( o C) Depth (m)

8 Buffer layer Tundra, Tuktoyaktuk The atmosphere Buffer Layer Vegetation canopy Snow cover Organic layer Mineral soil Ground thermal regime (Based on Luthin and Guymon, 1974) Subarctic boreal forest, Inuvik

9 Influence of vegetation and snow Ground temperature ( O C) Spruce forest, Tundra uplands B) O N D J F M A M Month

10 Ground ice

11 Active layer Active layer Surface subsidence Post-disturbance active layer Ice-rich permafrost

12 Permafrost gives rise to a unique landscape

13 Impacts of thawing permafrost on aquatic systems are not well understood

14 Climate warming and the NWT

15 Observed changes in mean annual air temperature 1948 to 2000 NWT (Meteorological Service of Canada, Environment Canada from Gunn et al. 2004)

16 Trends in the air temperature, Mackenzie Valley 2 Mean annual temperature ( C) Fort Simpson Inuvik year normal Burn et al., 2004

17 - Winter warming - More rain and snow?

18 Impact on the winter operating season Climate warming

19 Results - ice thickness Ice roads Ice thickness (cm) Mean winter temperature ( C) Todd Lake, C.R. Burn

20 April 1 to 15, mean temperatures ( and ) Mean (N=10) Warmest year Coldest year

21 Backfilling a sump containing unfrozen fluids Frozen spoils Drilling fluid Drilling fluid

22 Climate change impacts

23 Breakup of rivers 1950's 1960's 1970's 1980's 1990's 2000's 160 June June 4 Julian Day 150 Mean = day 152 = June1 May Annual peak level 5-yr running mean May 25 Decadal mean 140 May Date

24 Changing stream flow Baker Creek (Martin Lake outlet) Mean Daily Discharge: m3/s May 1991 Spring Summer Fall May 2009 May 2008 Jul & Aug 1988 Aug 2002 Oct 2005 Oct Sep

25 Storm surges and ecological change Regulatory monitoring Remote sensing Dendrochronology Dead Living Healthy Living Stressed Traditional knowledge Ring width index Hydrometric Year Vegetation

26 Shrinking ponds (Yoshikawa and Hinzman, 2003).

27 Talik adjustment due to warming Lake 3 o C Lake 5 o C Massive ice Permafrost -7 o C Talik (unfrozen) Permafrost -4 o C Talik (unfrozen) Cold permafrost Warm permafrost

28 Natural and infrastructure related stability DOT

29 Active layer deepening Active layer Water movement Ice-rich permafrost

30 Active-layer freezeback cm ground temperatures, fall 2009 Hummock Nov 11 Peatland Nov 28 Wetland Dec 17 1/10/09 1/11/09 1/12/09 1/1/10 Point bar Dec ground temperature ( C) Hummock Polygonal peatland Alluvial wetland Alluvial point bar Time

31 Climate warming and permafrost Mackay, 1974; GSC Burn and Kokelj, 2009; PPP

32 Impacts of thawing permafrost on aquatic systems are not well understood

33 Anticipating impacts and adapting How are things connected? People and Wildlife Trees plants and berries

34 Case Study: Permafrost MEGA-SLUMPS, Peel Plateau, NWT.

35 Cumulative Impact Monitoring and Research

36 An Ice-Cored Landscape

37 Landscape change on the Peel Plateau What are the changes on the landscape? What is driving the changes? What are the fluvial impacts?

38 Peel Plateau new terrain disturbances

39 Infilling of stream valleys Mega slump Debris dam lake 1 km

40 Largest disturbances known

41 Fort McPherson summer precipitation (mm) Precipitation (mm) * * * *? Year

42 Debris flow activity, hot and dry period, summer /06/2010 Sediment transport index (rate x width x surface lowering) 19/06/ /06/ /06/ /06/ /06/ Net radiation (Wm2) 0

43 Debris flow activity and precipitation, summer 2010 Sediment transport index (rate x width x surface lowering) /06/ /06/ /07/ /07/ /07/ /08/ Precipitation (mm) /20/2010 6/30/2010 7/10/2010 7/20/2010 7/30/2010 8/9/2010

44 Why are mega-slumps developing? 1. Slump headwall and toe AL Exposure debris Massive ice 2. Accumulation of debris AL 3. Intense rainfall and evacuation of debris AL Massive ice Massive ice

45 Infilling and stabilization

46 Why are mega-slumps developing? 1. Slump headwall and toe AL Exposure debris Massive ice 2. Accumulation of debris AL 3. Intense rainfall and evacuation of debris AL Massive ice Massive ice

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49 Growth of debris flow August 2010 June m Quickbird August 2008

50 Study catchments and water quality stations

51 Profound aquatic effects Conductivity of impacted and unimpacted streams 600 Conductivity (us/cm) Unimpacted Impacted Unimpacted Impacted TSS (mg/l) < to SO 4 < to 569

52 Impacted stream water level and net SW radiation (Wm 2 ) km 2 catchment Water level (ft) Net SW (Wm2) Days

53 Water level and turbidity undisturbed stream Turbidity (NTU) Rainfall events /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /07/ /07/ /07/ /07/2010 Stage (ft) 32.5 Turbidity (NTU) Stage (ft)

54 Turbidity and net radiation downstream of slump Turbidity (NTU) /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /06/ /07/ /07/ /07/ /07/2010 Net SW (Wm2) 0 Turbidity (NTU) Net SW (Wm2)

55 Impacts observed where less than 1% of catchment is affected

56 Changing environmental conditions, Peel River Dissolved sulphate, Peel River SO4/Ca ratio, Peel River SO4/Ca ratio y = 7E-05x R 2 = /25/1970 6/25/1973 6/25/1976 6/25/1979 6/25/1982 6/25/1985 6/25/1988 6/25/1991 6/25/1994 6/25/1997 6/25/2000 6/25/2003 6/25/2006 6/25/2009 Date

57 Conclusions Various landscapes will respond differently to climate change In order to adapt, changes need to be understood

58 Conclusions Thawing permafrost is causing aquatic environments to change Baker Creek (Martin Lake outlet) 9 8 May 1991 Mean Daily Discharge: m3/s Jul & Aug 3 May Aug 2002 Oct 2005 Oct 2008 May 2008 Sep

59 Conclusions Impacts are detectable at the large basin scale

60 Conclusions Understanding drivers of change is the knowledge base upon which cumulative impacts can be assessed and tracked Variability Processes Cumulative impacts - Mitigation

61 Climate change, permafrost and the North Integral part of northern environment Impacted by climate change Key consideration in all development Need best available information Northern capacity in science Ability to lead or direct research is limited Understanding and applying results Combine information from multiple sources

62 Northern based integrated monitoring system Community-based monitoring Government and academic monitoring and research Industry monitoring The Land Decision making, co-management, adaptation stewardship

63 Thank you