Your Forest in a Changing Climate
Climate Adaptation Project Case Study
The private woodlot owners of New Brunswick are a varied people. A 2019 survey (Woodlot Owner Survey Report) found that they include all ages, all genders, all occupations and salary ranges. They also have a variety of different goals and objectives for their woodlots; including timber volume, recreation, and biodiversity to name a few. Additionally, woodlot sites can range from stony and hilly to former farmland, prone-to-flooding to susceptible-to-drought, dense tree stands to previously clear-cut. Private woodlots account for 30% of New Brunswick’s forests and there are over 42,000 private woodlot owners in New Brunswick. For a small province there is a lot of diversity within this group.
To be able to explore how climate change will affect private woodlots in New Brunswick in the future we have selected and are in the process of studying four private woodlot sites that represent not only different site conditions and stand types throughout the province but also the different goals of their owners. Our case study includes a sample plot area on each woodlot consisting of a one acre control (i.e. left untreated), one acre with traditional silviculture treatments applied, and one acre that is treated using recommendations from the climate adaptive silviculture prescription tool (available for download here).
The four woodlots used for the case study are each in a different eco-region of the province. They have their own unique features and site conditions, yet are still considered quite typical New Brunswick woodlots. Any woodlot owner in NB should be able to find similarities to their own woodlot with at least one of these sites.
The sample plot areas will remain in place for years to come, allowing for further study that will improve our knowledge about the effects of climate change on the Acadian Forest Region.
The New Brunswick Federation of Woodlot Owners (NBFWO) is a not-for-profit association that promotes the economic and social interests of NB’s private woodlot owners by representing their views with a united provincial voice. We coordinate educational and project opportunities on topics of interest to woodlot owners. We collaborate with Forest Products Marketing Boards and other like-minded organizations that are providing services to woodlot owners and act as a networking hub for all things woodlot related.
In the fall of 2018, the NBFWO was chosen to participate in Natural Resource Canada’s Building Regional Adaptation Capacity and Expertise program (BRACE). This federal program was developed in response to the Pan-Canadian Framework on Clean Growth and Climate Change report where it was identified that building capacity is needed to translate knowledge into climate change adaptation action. The BRACE program goals are to increase the ability of communities, organizations, small and medium-size enterprises and practitioners to incorporate climate change into their planning and management and to be more climate-resilient.
As part of the NBFWO’s BRACE project, and with additional funding from the Government of New Brunswick’s Environmental Trust Fund, this case study was created to demonstrate a range of approaches that make practical, ecological, and economic sense to woodlot owners and that demonstrate how peers are applying climate adaptive silviculture prescriptions.
Four privately owned woodlots located throughout New Brunswick were chosen to highlight typical forest stand conditions found in the province and explore what changes to can be made to traditional forest silviculture management that will allow these woodlots to become more resilient to the changing climate conditions. Each of these woodlots will be explored in detail later in the case study, but we will begin with some information about climate change and the potential impacts to the Acadian Forest Region.
WHAT IS A CHANGING CLIMATE?
To understand climate change, we first need to understand the difference between weather and climate. Weather refers to the actual atmospheric conditions that are being experienced now. It also includes changes that are forecast over the next few days, for example, in temperature and rainfall. Climate refers to the kind of weather that's typically expected in a region. This includes describing the range of conditions that are possible.
Climate change is a long-term shift in the average weather conditions of a region, such as temperature, rainfall, and windiness. Climate change means that the range of conditions expected in many regions will change over the coming decades. This means that there will also be [increases in the frequency and intensity of] extreme conditions.
The climate varies naturally from year to year and decade to decade. This is caused by natural processes linking the atmosphere, ocean and land, as well as variations in heat output from the sun. In addition to changes in climate that are caused by natural climate variability, climate change [is] caused by human activity. The kind of climate change we are experiencing now is being caused primarily by human activities that [have and are releasing] greenhouse gases to the atmosphere (Climate Change Concepts, 2022).
In Figure 1, below, you can see the sun is the source of energy for Earth (1). Some of the sun’s energy is reflected back to space (2), but the rest is absorbed by the atmosphere, land, and ocean and re-emitted as longwave radiation (infra-red energy). Some of this infra-red energy is absorbed and then re-emitted by greenhouse gases in the lower atmosphere, trapping heat in the lower atmosphere and reducing how much is radiated to outer space. This process is known as the greenhouse effect (3). Changes to the amount of incoming solar radiation (1), the amount of reflected sunlight (2), and the heat-trapping capacity of the atmosphere (3) cause climate warming or cooling. Factors that drive such changes are called climate drivers or climate forcing agents.
Figure 1 The greenhouse effect and key drivers of climate change.
The greenhouse effect is a natural and necessary process. This keeps the temperature at the Earth’s surface around 15 degrees C, and without the greenhouse effect, life on Earth, as we know it, would not be possible.
However, the heat trapping capacity of the atmosphere has changed because of human activities:
● Climate warming decreases the amount of snow and ice cover on Earth which reduces the Earth’s albedo (reflectivity). Darker land and water surfaces exposed by melting snow and ice absorb more incoming solar radiation, adding more heat to the climate system and amplifying the initial warming, in turn causing further melting of snow and ice.
● The combustion of fossil fuels emits CO2 and other GHGs, considerably increasing their concentration in the lower atmosphere. Moreover, this combustion is associated with the emission of pollutants which form aerosols of various chemical compositions, which absorb solar radiation and create a net warming effect in the atmosphere. (Canada’s Change Climate Report 2019)
Figure 2 simulated historical and projected temperature in Canada.
*[The “by the end of this century values” show the projected changes in mean annual temperature for the 2081-2100 time period relative to the 1986-2005 baseline time period.]
The climate has always been changing. What is different now is the [rate of climate change and that] the additional effects from human activities (greenhouse gases, aerosols, changes in land use all combined) have become clearly discernable over the past several decades.
A report published by the IPCC (Intergovernmental Panel on Climate Change) in 2018 maintains that human activity has caused a warming of approximately 1.0°C, with a range of 0.8°C to 1.2°C over the whole globe since 1880.
But that is the average. The figure below also illustrates the fact that an average global warming value does not represent the reality in all local settings. For example, some regions (in purple) have experienced close to a 2.5 degree warming. These differences will lead to much different impacts to individual regions.
Figure 3 Global observed change in surface temperature 1901-2012.
The number of climate related events are increasing; extreme temperatures, droughts, forest fires, and tropical storms. Remember the Fort McMurray, Alberta wildfires? How about the drought followed by heavy rains that flooded British Columbia in 2021? These were destructive events that climate researchers have concluded were made more damaging due to climate change. And we can expect the numbers to grow. Between 1980 and 2018 (only 28 years) North America saw an increase of approximately 600 hydrological and climatological events (from 250 to 850).
Figure 4 Number of hydrological and climatological events in North America 1980-2018.
CLIMATE CHANGE IN NEW BRUNSWICK
“The forests of the Maritime provinces of Canada (a.k.a. the Maritimes), as well as the forests of the Gaspé region of Quebec and those of the New England states, form a unique forest type known as the Acadian forest. The Maritimes, and indeed all of the Acadian Forest Region, has been historically located at the very northern limit of a temperate climate – a temperate-boreal (i.e. hemiboreal) transitional climate. Many of the temperate species found in the Maritimes are found at the northern limits of their historical ranges. Likewise, many of the boreal species found in the Maritimes are at the southern limits of their historical ranges. Unlike the more continental climates of hemiboreal forest regions/eco-zones west of the Maritimes, the historical climate of the Maritimes has been relatively moderated by the North Atlantic, where precipitation has not been a limit to growth, at the regional scale, and where summers have been cooler and winters milder, than more continental climates to the west. There is, however, considerable variability in local climates (i.e. ecoregions) within the Maritimes, due to proximity to the ocean and changes in elevation. For example, western New Brunswick has a significantly more continental climate than ecoregions closer to the coast, and the highest elevations in New Brunswick have historically had true boreal climates.” (Climate Change Resilience and Carbon Storage Silvicultural Prescriptions for the Acadian Forest Region Appendix B - Supporting Information v.1.0, 2019)
The effects of climate change are being experienced in New Brunswick and are expected to further impact the province in the future. Climate change will affect all aspects of the environment, economy and society in New Brunswick.
The environmental effects of greenhouse gas (GHG) emissions will continue to increase unless action is taken to limit their production. However, efforts to reduce greenhouse gas emissions cannot stop climate change from occurring. Therefore, New Brunswick must also take measures to adapt to the effects of climate change.
HOW HAS CLIMATE CHANGE AFFECTED NEW BRUNSWICK?
The Province is already experiencing the impacts of climate change. New Brunswick’s mean annual temperature has already increased by 1.1°C in the last 30 years. Rising sea levels have also increased the risk of flooding and coastal erosion. Historically, the province has experienced extreme weather events that have caused catastrophic damages.
Since December 2016, a number of extreme these weather events have occurred including a snow and freezing rain storm which moved across the province causing a long duration of power outages and destroying much of the electrical distribution infrastructure in the Acadian Peninsula and resulted in long duration power outages. In 2018 and 2019, the province experienced back-to-back spring flooding along the St. John River. The 2018 flood causing was record setting flooding and caused the highest damage costs of any flood event. Additionally, in late summer of 2019, post-tropical storm Dorian brought high winds and rain to the region that resulted in extensive property, infrastructure, and shoreline damage.
HOW WILL CLIMATE CHANGE AFFECT NEW BRUNSWICK IN THE FUTURE?
Climate projections datasets indicate the province will become warmer, wetter, stormier and will experience rising sea levels, which represents significant challenges and opportunities for New Brunswick’s communities and resource sectors.
In New Brunswick, projections indicate an anticipated increase of approximately 5°C across the province, with some areas becoming warmer than others. Projections also indicate a substantial increase in very hot days (days above 30°C) and a longer growing seasons. Potential effects of warmer temperatures include an increase in risk to water quality, increase in pests/invasive species, more freeze-thaw events or potential for health impacts such as heat stress.
Annual precipitation is projected to increase with a shift toward more rain days and less snowfall days. This will result in Potential effects of changing precipitation include increased run-off, flooding and erosion and increased risk of damage to and failure of key infrastructures.
High intensity precipitation events are becoming more common. Projections indicate that New Brunswick can expect more extreme and variable weather patterns. Potential effects of stormier weather will include increased damage to trees and to infrastructure such as buildings, homes and critical services like the electrical grid from high winds, ice storms and extreme storm surges.
Rising Sea Levels
Sea level rises primarily as a result of the melting of glaciers and ice caps and the rate at which they are melting has increased due to global warming. In New Brunswick, sea level is predicted to rise by approximately 1m by 2100. Sea level rise combined with high tidal cycle and storm surge can lead to increased flood elevations and increased risk of coastal flooding and coastal erosion risks, potential loss of natural habitat and damage to infrastructure.” (Climate change affecting NB 2022)
ASSESSING RISKS AND VULNERABILITIES
The number one recommendation for every woodlot owner is ‘know what you have’. Take a survey or inventory of the conditions and species that are present on your woodlot(s)there. Your local Forest Products Marketing Board can help you with this task. Before you can decide on a plan for the future, you need to know what species you have and, what are the growing conditions are.; sunny, shady, rocky, shallow soil, prone to flooding, risk of strong winds, etc.
Milder winters and warmer springs could also increase vulnerability to Balsam Woolly Adelgid, Spruce Budworm outbreaks, and other potential pests and diseases.
In 2018, Community Forests International summarized the projected effects from climate change on trees and the capacity to persevere for those tree species. This review is highly recommended reading for anyone in New Brunswick, or the rest of the Maritimes, taking climate change into consideration when adjusting their silviculture management. The table below is a summary of the probable future for certain native tree species from that report.
Figure 5 Table of native tree species and their probable futures.
CASE STUDY OVERVIEW
The objective of this case study is to build the capacity of woodlot owners to make management decisions that consider climate change, through education and implementation of best management practices. The result will be forests that are more climate resilient, and a resilient forest is an important component of a healthy ecosystem.
Whatever the goals an owner may have for their woodlot – whether it is increasing timber volume, creating wildlife habitat, or just for their own recreation, the same best management practices can be applied to woodlot management. And remember, what was considered ‘best’ 30 years ago, may not be what the experts agree on today.
As part of the NBFWO BRACE project, we specifically wanted to train foresters, forest technicians, and woodlot owners to use and incorporate New Brunswick-generated climate change adaptation guidelines and tools in woodlot management plans and ongoing silviculture practices. The silviculture tools created, and additional information curated on the NBFWO website as part of this project, is designed for use in the Acadian Forest Region. There is a lot of great research ongoing in the Boreal forest region, but it is harder to find information that relates to closer to home. We are working to help change that.
Figure 6 The locations of the four woodlot sites (Google Earth Image Map):
Site 1: Hazen & Karen McCrea, South Tetagouche, NB
Site 2: Jorg & Gloria Beyeler, Grand Lake, NB
Site 3: Conrad & Elspeth Leroux, Windsor, NB
Site 4: McCrea Farms, Shannon, NB
The 4 woodlots used for the case study are each in a different eco-region of the province. They have their own unique features and site conditions, yet are still considered quite typical New Brunswick woodlots.
Any woodlot owner in NB should be able to find similarities to their own woodlot with at least one of these sites; whether they have a lot of balsam fir and are wondering what to do with it, or if they want to add some species diversity to a solid softwood stand, or are dealing with a damp, mossy region.
These generous owners have allowed us to set up a study area on their lands. The study area is approximately 3 acres of a relatively homogenous stand type, which is then divided into 3 approximately one acre plots;
Control - Plot 1 is a control area that will be left untreated.
Traditional - Plot 2 is treated with what is considered a ‘traditional’ silviculture treatment (for example clear cutting).
Climate adaptive - Plot 3 is treated with what is considered a ‘climate adaptive’ silviculture treatment (for example planting climate resilient species).
The Climate Adaptive silviculture prescription for each site was created using the Climate Adaptive Silviculture Prescription Tool created for the BRACE project. On each woodlot study area, foresters took sample plot readings to establish the species on site and timber volumes. In the case of Site 3, the regeneration was still too young to obtain timber volume so stems per hectare (stems/ha) were measured instead. They took note of average stand age, percent crown closure, regeneration status, ground conditions and the history of the area were noted.