Download FORESTS IN A CHANGING CLIMATE: IMPACTS AND

FORESTS IN A CHANGING CLIMATE: IMPACTS AND ADAPTATION IN ONTARIO
Annette Morand and Al Douglas
Ontario Centre for Climate Impacts and Adaptation Resources at MIRARCO / Laurentian University, Sudbury, Ontario, Canada
[email protected], [email protected]
WHAT DOES THIS MEAN FOR ONTARIO FORESTS?
CLIMATE CHANGE IS REAL, AND THE EVIDENCE IS COMPELLING
There is overwhelming evidence that climate change is real, and we are already
experiencing changes in temperature, precipitation, and extreme weather. In
Canada, average surface air temperature has increased by 1.5°C between
1950 and 2010 (Bush et al., 2014). Although the strongest trends have been
observed in the north and west of the country, warming has been observed
consistently across all of Canada (Bush et al., 2014; Vincent et al., 2012).
Between 1948 and 2008, almost every region in Ontario experienced an
increasing temperature trend, with mean annual temperature increasing by
1.4°C (CCDS, 2009). This seemingly small number may look insignificant, but
small changes in average temperatures can result in significant impacts.
Daily precipitation data demonstrate that Canada has generally become wetter
in recent decades, with an increase in average annual precipitation of
approximately 16% between 1950 and 2010 (Bush et al., 2014). In Ontario, the
southern region has experienced increases in precipitation, however lack of
monitoring stations in the north make it difficult to detect strong precipitation
trends (Bush et al., 2014). Warmer temperatures have also impacted the type
of precipitation; several regions of Canada and Ontario have experienced a
decrease in snowfall and an increase in rainfall (Mekis and Vincent, 2011).
These graphs show trends in annual mean temperature (left) and precipitation
(right) from 1950-2010. Upward- and downward-pointing triangles indicate
positive and negative trends, respectively. Filled triangles correspond to trends
significant at the 5% level. The size of the triangle is proportional to the magnitude
of the trend (Vincent et al., 2012).
A NATIONAL CLIMATE CHANGE ASSESSMENT
Climate plays a large role in determining forest distribution, composition, productivity, dynamics and disturbance regimes. As a result, climate
change is projected to have far-reaching consequences for Ontario’s forest sector (Lemmen et al., 2014).
CHANGES IN PRODUCTIVITY: Net impacts of climate change on forest
productivity will be regionally and locally specific. In some regions the
warmer, wetter climate will improve growing conditions, while other
regions will experience higher evaporation rates and changing soil
conditions due to drought, which could lead to early stand dieback
and breakup (Murphy, Chretien and Brown, 2012; Williamson et al.,
2009; Lemmen et al., 2014).
FIRE: Climate model projections indicate that fires are likely to occur
more frequently, and the length of Ontario’s fire season will likely
increase (Colombo, 2008). Overall area burned is projected to increase
between 50 and 300% by 2080, with most of the increase occurring in
the remote northwestern portions of the province (Williamson et al.,
2009).
PEST EPIDEMICS AND DISEASES: Ontario will likely experience more
frequent, severe and widespread outbreaks of pests and diseases. For
example, climate change is expected to result in increased Spruce
Budworm damage in northern areas of Ontario and decreased Spruce
Budworm damage in the southern areas (Williamson et al., 2009;
Government of Ontario, 2015).
SOCIO-ECONOMIC IMPACTS: Climate change will likely affect the
quality and quantity of timber supply, resulting in financial impacts to
the forest industry and those industries that rely on forest harvests
(e.g. construction, manufacturing) (NRTEE, 2011). Forest fires are also
a threat to human health and safety; therefore, the projected increase
in fire due to climate change will mean higher costs associated with
human protection and community evacuations (Lemmen et al., 2014).
DROUGHT AND OTHER EXTREME WEATHER EVENTS: Damage from
extreme weather events is expected to increase as Ontario experiences
more frequent and intense weather events. For example, more
frequent flooding, extreme temperatures and wind events will damage
trees as well as infrastructure and equipment required for forest
management and related industries (e.g. mills, maple syrup
production, transportation routes).
IMPACTS ON CARBON STORAGE: Forest ecosystems play an important
role in climate change mitigation as they store carbon. The projected
increase in disturbances (e.g. drought, fire, pests) can reduce the
amount of carbon storage capacity in Ontario forests (Amiro et al.,
2009; Michaelian et al., 2011).
CUMULATIVE IMPACTS: Damage caused by increasing pest and disease
occurrence may increase vulnerability to forest fires and extreme
events. This combination of impacts has a multiplying effect on climate
risk and can complicate forest resource management adaptation
efforts.
CHANGES IN COMPOSITION: Warming will permit the expansion of the
northern range limit of many species, however actual species
migration will not keep pace with the rate at which climatically suitable
niches expand. As a result, the extirpation of some vulnerable species
is likely to occur due to less favourable climatic conditions (Williamson
et al., 2009).
In Ontario, warming temperature trends and changing precipitation patterns
are expected to result in a variety of environmental, social and economic
impacts. Some of these impacts include: reduced ice cover on the Great Lakes,
increased snowfall, increased freeze-thaw cycles, increased viability of pests
and diseases, increased flooding, increased soil erosion, degraded water
quality, earlier peak flow in streams and rivers, decreased total flow in
streams and rivers, and potential for drought conditions and forest fires. Since
warmer air can hold more moisture, climate change will also result in more
frequent and intense extreme weather events (Warren and Lemmen, 2014).
PROJECTED CHANGES IN WINTER TEMPERATURE PROJECTED CHANGES IN SUMMER TEMPERATURE
IN ONTARIO (2046-2065)
IN ONTARIO (2046-2065)
A Ministry of Natural Resources fire ranger looks
back as a camp protected by sprinklers is
threatened by a forest fire near Red Lake, ON,
August 4, 2011 (The Canadian Press, 2011).
These risks are projected to increase significantly in the future. Forest
managers will experience these climate impacts first-hand, and will
require access to the best information available in order to develop
and implement adaptation measures.
Much of the information presented here can be found in the
latest national assessment document. To learn more, please visit:
www.nrcan.gc.ca/environment/resources/publications/10766.
Climate change will favour
disturbance-adapted species such as
aspen and white birch (Williamson et
al., 2009).
Canadian Council of Forest Ministers (CCFM)
www.ccmf.org/english/coreproducts-cc.asp
NRCan National Assessment
www.nrcan.gc.ca/environment/resources/publications/10766
REFERENCES
Trees have natural physiological and genetic adaptive abilities that allow adjustment to changes in the environment, however expected climate
change impacts will likely surpass this inherent adaptive capacity, therefore Ontario’s forest sector will need to adapt. Adaptive management
approaches involve ongoing research, monitoring and evaluation with the intent of informing future management policy and practices, and
allowing for flexibility in the face of the uncertainties inherent in climate change (Lemmen et al., 2014).
Amiro, B. D., Cantin, A., Flannigan, M. D., and De Groot, W. J. (2009): Future emissions from Canadian boreal forest
fires. Canadian Journal of Forest Research, v. 39, no. 2, p. 383-395.
EXAMPLES OF ADAPTATION:
ACTION IN ONTARIO:
CCDS [Canadian Climate Data and Scenarios] (2009): 2050s Ensemble Scenarios (1961-1990 baseline). Canadian Climate
Change Scenarios Network. Editor: N. Comer. Adaptation and Impacts Research Section, Environment Canada.
http://ccds-dscc.ec.gc.ca/?page=ensemblescenarios-2050s.
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Temperature projections for winter season (December-February) and summer season
(June-August) for 2046-2065 under an RCP8.5 scenario, 50th percentile (CCDS, 2015).
The Spruce Budworm is the most destructive pest of spruce
and fir forests in North America. Spruce budworm damage will
likely increase in northern Ontario and decrease in the south
(Williamson et al., 2009; Government of Ontario, 2015).
WHAT CAN WE DO TO ADAPT?
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(°C)
Chapter 3 of the National Assessment is focused on Natural Resource
industries, such as forestry. In Ontario, climate impacts such as
increasing forest fires, more frequent and widespread outbreaks of
pests and diseases, and changing forest composition have been
observed.
Forestry Adaptation Community of Practice (FACoP)
www.ccadaptation.ca/facop
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(°C)
The assessment, Canada in a Changing
Climate: Sector Perspectives on Impacts and
Adaptation, is an update to the 2008 report,
From Impacts to Adaptation: Canada in a
Changing Climate. The report includes chapters
on natural resources (including forestry), food production, industry,
biodiversity and protected areas, human health, water and
transportation infrastructure, and adaptation.
FOR MORE INFORMATION…
WHAT TYPE OF CLIMATE CAN WE EXPECT IN THE FUTURE?
With the help of global climate models, scientists are able to simulate changes
in climate based on a set of scenarios of anthropogenic forcings. In northern
countries such as Canada, the largest temperature change is likely to occur
during the winter season (e.g. winters in northern Ontario are projected to be
5 to 7°C warmer). Furthermore, projections suggest that annual precipitation
is expected to increase in Ontario, with the largest changes in the northeast
and the lowest changes in the western part of the province (CCDS, 2015).
In 2014, the Climate Change Impacts and
Adaptation Division of Natural Resources
Canada released a national science assessment
that presents the latest knowledge on climate
change impacts and adaptation for Canadians.
Employ assisted migration techniques (i.e. the human-assisted
movement of species in response to climate change) in order to
maintain vulnerable native species and introduce new future
climate-suitable species.
Integrate principles of adaptive management and an ecosystembased approach into resource management plans.
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Use a diverse mix of native tree species in reforestation to reduce
the risk of loss to pests and diseases.
Enhance early detection methods and rapid response of new
forest pest infestations.
Use prescribed burning or other ground cover management to
reduce the risk of catastrophic fire.
Incorporate results from climate change scenarios and
vulnerability assessments into planning initiatives (MOE, 2012).
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The City of Greater Sudbury considered climate changes when
planning forest floor transplants as part of their re-greening
program. Species likely to thrive in northerly locations were
identified and transplanted with forest floor material in the target
area (CAP, 2012). This is an example of assisted migration.
The City of Toronto Urban Forestry Services has employed new
planting techniques that promote street tree health and provide an
element of protection for urban forests against climate change
impacts (CAP, 2012).
In 2013, the Canadian Council of Forest Ministers (CCFM)
conducted a review of several case studies in which forestry-based
climate change vulnerability assessments had been carried out.
These included assessments in the Clay Belt region and the Lake
Simcoe watershed in Ontario. The case studies identified climate
risks, vulnerable regions, and provide data to inform decisions on
adaptation in the region.
In 2012-2015, CCFM produced a series of reports on Adapting Sustainable Forest Management to Climate Change which examines the impact of
climate change on sustainable forest management and provides a suite of tools and products that improve the ability of the forest sector to adapt to
climate change, and guide forest managers in understanding and carrying out vulnerability assessments. For more information on the CCFM climate
change documents, please visit www.ccmf.org/english/coreproducts-cc.asp.
Bush, E.J., Loder, J.W., James, T.S., Mortsch, L.D. and Cohen, S.J. (2014): An Overview of Canada’s Changing Climate; in
Canada in a Changing Climate: Sector Perspectives on Impacts and Adaptation. (ed.) F.J. Warren and D.S. Lemmen.
Government of Canada, Ottawa, ON, p. 23-64.
CAP [Clean Air Partnership] (2012): Accelerating Adaptation in Canadian Communities: Case Studies.
www.cleanairpartnership.org/accelerating_climate_change_adaptation_case_studies.
CCDS [Canadian Climate Data and Scenarios] (2015): Plots of Climate Projections in Canada from CMIP5 data.
www.cccsn.ec.gc.ca/index.php?page=download-cmip5.
Colombo, S.J. (2008). Ontario’s Forests and Forestry in a Changing Climate. Ontario Forest Research Institute, Ontario
Ministry of Natural Resources and Forestry. Climate change research report; CCRR-12 p. 31.
Government of Ontario (2015). Spruce Budworm. www.ontario.ca/environment-and-energy/spruce-budworm.
Lemmen, D.S., Johnston, M., Ste-Marie, C. and Pearce, T. (2014): Natural Resources; in Canada in a Changing Climate:
Sector Perspectives on Impacts and Adaptation. (ed.) F.J. Warren and D.S. Lemmen. Government of Canada,
Ottawa, ON, p. 65-98.
Mekis, É. and Vincent, L.A. (2011): An overview of the second generation adjusted daily precipitation dataset for trend
analysis in Canada. Atmosphere-Ocean. v. 2, p. 163-177.
Michaelian, M., Hogg, E. H., Hall, R. J., and Arsenault, E. (2011): Massive mortality of aspen following severe drought
along the southern edge of the Canadian boreal forest. Global Change Biology, v. 17, no. 6, p. 2084-2094.
MOE [Ministry of the Environment] (2012): Portfolio of Climate Change Adaptation Recommendations: Northern
Ontario Boreal.
Murphy, B.L., Chretien, A.R. and Brown, L.J. (2012): Non-timber forest products, maple syrup and climate change. The
Journal of Rural and Community Development, 7(3), p. 42-64.
NRTEE [National Round Table on the Environment and Economy] (2011): Paying the price: The economic impacts of
climate change for Canada. Ottawa, ON. p. 162.
The Canadian Press (2011): Northwestern Ontario breaks 50-year forest fire record.
http://ottawa.ctvnews.ca/northwestern-ontario-breaks-50-year-forest-fire-record-1.687297.
Vincent, L.A., Wang, X.L., Milewska, E.J., Wan, H., Yang, F., and Swail, V. (2012): A second generation of homogenized
Canadian monthly surface air temperature for climate trend analysis. Journal of Geophysical Research. v. 117,
D18110, p. 13.
Warren, F.J. and Lemmen, D.S., editors (2014): Canada in a Changing Climate: Sector Perspectives on Impacts and
Adaptation. Government of Canada, Ottawa, ON, p. 286.
Williamson, T.B., Colombo, S.J., Duinker, P.N., Gray, P.A., Hennessey, R.J., Houle, D., Johnston, M., Ogden, A. and
Spittlehouse, D.L. (2009): Climate change and Canada’s forests: From impacts to adaptation. Sustainable Forest
Management Network and Natural Resources Canada, Canadian Forest Service, Northern Forest Center,
Edmonton, Alberta.