Written by OSPE Subject Matter Expert Dr. Gail Krantzberg
Dr. Gail Krantzberg is Professor and Director of the Masters of Engineering and Public Policy Programs at McMaster University. Gail is an environmental scientist by training, a Senior Great Lakes Policy Analyst by career, and has authored five books and more than 160 articles on issues pertaining to ecosystem quality and sustainability.
The magnitude of the Laurentian Great Lakes water system is difficult to appreciate. The Great Lakes are the largest system of fresh surface water on earth, containing roughly 18 percent of the world’s inventory – or 23,000 km3, covering a total area of 244,000 km2. This tremendous volume is hard to conceptualize, but if it were spread over the adjoining 48 states, its waters would average about 2.9 meters (9.5 feet) deep.
This precious resource is susceptible to ever increasing atmospheric carbon dioxide concentrations, which may be modifying North America’s climate at a rate unprecedented in history.
Climatologists, using the General Circulation Model (GCM), have attempted to estimate how the increase of carbon dioxide emissions will affect the climate in the Great Lakes basin. Several of these models show that at twice the carbon dioxide level, the climate of the basin will be warmer by 2-4°C than at present. Warmer climates mean increased evaporation from the lake surfaces, and evapotranspiration from the land surface of the basin. Due to evaporation, the resulting decreases in average lake levels are predicted to be from half a metre to two metres, depending on the model used.
Increases in evaporation in the Great Lakes could result in:
- Soil moisture deficits
- Reduction in base flows in streams
- Periods of lower lake levels and more droughts throughout, affecting the ability of the system to recharge and flush contaminants
- Large declines in lake levels could also increase the concentration of contaminants in the Great Lakes, and would adversely affect coastal habitats
- Increased evapotranspiration and soil moisture reduction, coupled with increased winds associated with more frequent and intense storms, could worsen soil erosion and sedimentation with corresponding high sediment and nutrient loadings to streams and tributaries, which could smother fish habitat and cause pollution in nearshore zones
- Precipitation intensity will increase to a degree that a higher percentage of rainfall will be runoff rather than infiltration and groundwater recharge, resulting in less water available as soil moisture for terrestrial and aquatic life
To combat these issues, the Great Lakes Water Quality Agreement (GLWQA), a bi-national agreement between Canada and the United States, was created. It was first signed in 1972 to identify shared priorities and coordinate actions to restore and protect the chemical, physical and biological integrity of the waters of the Great Lakes. The agreement was amended in 1987 and 2012, and now serves to promote an interest in climate change and related conservation efforts.
In the 2012 Protocol, the governments of Canada and the United States committed to a new objective to “enhance the long-term effectiveness of management strategies for restoring and protecting Great Lakes water quality by understanding and considering climate change impacts.”
Adaptation measures that focus on reducing vulnerability of the system to both current and future climate variability and extreme events are necessary, regardless of the rate of future climate change.
Here, adaptation measures are defined as those actions which may be taken to prevent or reduce damage from climate change by responding to the risks posed to human economic and social activities, and to natural environment, making them more climate resilient. Adaptation actions may involve behavioural changes, operational modifications, technological interventions, revised planning, as well as improved regulations and legislation.
Many adaptation measures are ‘no-regrets’ options, characterized by measures that would generate net social and/or economic benefits irrespective of whether or not climate change occurs. They generally have the double benefit of reducing short-term exposure to climate variability, as well as long-term vulnerability to climate change. Examples of water ‘no-regrets’ adaptation measures include increased efficiency in the use of water, the designation of flood hazards, and measures to reduce water demand and improve infiltration.
The variety of climate change repercussions call for highly diverse adaptation measures. Many of the changes expected will impact multiple components of the ecosystem. For example, increasing temperatures are linked to the invasion of exotic species that can disrupt biological systems and water chemistry. Temperature rise also corresponds to increasing incidents of algae and water level declines, both of which impact water quality and human health. Intense precipitation events allow for sometimes harmful runoff to enter the lakes, impacting fish and wildlife populations, causing beach closings, and exacerbating fish consumption with long term implications.
At present, most Great Lakes states and provinces have adopted climate action plans that provide Green House Gas (GHG) emission inventory data and make GHG emission reduction recommendations. There is a general emphasis on the environmental risks and the value of reducing GHG emissions, but very little attention has been given to adaptation. Where plans do exist, most of the focus has been placed on responses to changes in water availability and demand, and how to manage increased demand for water.
On a municipal level, the Great Lakes and St. Lawrence Cities-Initiative launched the Municipal Adaptation and Resiliency Service (MARS) in January 2014 for its member municipalities to help them accelerate and expand their adaptation activities. This initiative will provide a portal for municipal members to access climate and adaptation information and resources that will also serve as an interactive forum for information sharing.
In the Great Lakes region, there are many individuals, organizations, and agencies engaged in climate change adaptation efforts. Most efforts to date have focused on building the capacity of practitioners to understand what climate changes are taking place and develop coping strategies. However, there are fewer examples of adaptation being implemented in practice. A number of challenges explain why implementation is limited. These include:
- Lack of financial capacity and funding to support and sustain initiatives
- Lack of institutional capacity, including limited staff expertise in mitigation, adaptation planning and implementation
- Limited engineering and science support for technical modeling of climate projections and the uncertainty in results
- Complexities of multi-sector coordination and limited information sharing across agencies
- Lack of social and community involvement, including lack of public concern or confidence in climate science
- Limited political support of climate initiatives and lack of enforced policy
- Limited examples of precursor adaptive studies that have shown effective adaptation solutions
In order to promote and sustain future climate adaptation initiatives, it is important to engage the community in the importance of adaptation measures. In order to gain public favour, it will be necessary for practitioners to identify the most applicable data, models, and tools that can support adaptation efforts and make these actions tractable within a public forum.
Efforts to improve climate adaptation efforts must include improved collaborative efforts among agencies and sharing of information, including engaging in international efforts, improved capacity for technical analysis, and action based strategies that include monitoring, evaluation, and “reset”. In the end, all efforts of this nature will help make the Lakes Great.