Commentary
by Robert Hughes
Adaptation Coordinator, New Brunswick Climate Change Secretariat, New Brunswick Department of the Environment, Fredericton, NB.
Coastal erosion. Storm surges. Torrential rains. Hurricanes. Washouts and inland rivers bursting their banks.
“So what?” you may say, “That’s life around here. Inconvenient now and then, but we expect it.” True enough. Severe weather is a fact of life in New England and the Canadian Atlantic Provinces, and accounts of floods, angry seas, shipwrecks and how people got though them are an accepted and important part of the region’s heritage.
Recently though, many have begun to take a serious look at these sorts of events and their impacts, to try to understand them from a new viewpoint. What if we are entering a period where weather events that affect the Gulf of Maine and the surrounding lands are going to be stronger and more destructive than those we normally expect? What if these events create more damage from high winds, more frequent intense rainstorms, higher storm surges, and more severe erosion and damage to ecosystems and property?
What is “normal” now? Are we already in a new world order of weather?
Those working in the rapidly-evolving field of climate change adaptation would generally agree that even if the jury may be out on some of the details, the verdict is clear enough—the weather really is changing, and we’re getting a better feel for what some of those changes may look like. Mostly, what we are seeing is agreeing quite closely with the predictions of global climate models being run by weather agencies around the world.
Higher temperatures will mean more energy for the water cycle and weather systems. Warmer air holds more water, which translates into bigger storm downpours, maybe stronger hurricanes, less snow cover in winter and more winter thaws. At the same time, higher temperatures lead to more water uptake from the land by evaporation and use by plants. Surprisingly then, even if precipitation goes up, increased runoff and evaporation may actually reduce the water available for groundwater recharge and sustaining river base flows.
Add to this picture rising sea levels, possible changes to water temperatures and currents, and the complexity of possible climate change impacts on the region can soon start to look overwhelming, like something we might never be able to properly understand, let alone effectively tackle.
Despite that, everyday decisions still have to be made. Resources are being applied to advance the science and policy of adaptation to climate change, understanding that there are benefits to planning, which take changing future conditions into account. One thing is clear: adapting to climate change is not optional. Changes are coming, whether we like it or not. But there are many ways of planning to be ready for change.
Human cultures have always adapted to climate change over long and short time scales, but the historical approach has been reactive, and based on the assumption that what has just been happening will go on happening. This has not always served people well, but there did not seem to be much of an alternative. Now, the availability of many advanced climate models offers the chance to plan ahead with more confidence. There is no doubt that sea levels will go on rising, global temperatures will continue to increase, and changes to the hydrological cycle will be significant.
With more detailed climate guidance to hand and with the realisation that significant impacts are unavoidable, communities around the world are starting to pay serious attention to adaptation. Some communities in Atlantic Canada are now in the midst of a major climate adaptation exercise known as “The RAC.” This stands for “Regional Adaptation Collaborative,” an effort that puts emphasis not only on practical answers to questions that are pressing now, but also towards fostering change among those who design structures, manage land and water, and make community decisions, so that climate-smart planning becomes the normal way of doing business.
The RAC is a program developed by Natural Resources Canada and is being applied across Canada to improve climate change adaptation decision-making. It is based on extensive partnerships between all levels of government, planning authorities and research institutions. There are six official RAC projects, in British Columbia, the Prairies, the Northern RAC (which includes the Yukon, Northwest Territories and Nunavut), Ontario, Quebec and Atlantic (which includes all four Atlantic provinces). Projects in the Atlantic region kicked off officially during 2010 and all are planned to be complete by the end of 2012.
In this region, the focus is on assessing community vulnerabilities to climate change, and studying solutions for concerns with inland and coastal flooding and erosion, impacts on infrastructure and groundwater, stormwater management, and lands in coastal areas protected from flooding by dikes. The total budget for projects in the region is over $8.4 million.
Atlantic RAC projects are taking place in communities of all sizes, from small rural centres such as Richibucto, NB (about 2,000 residents) to major regional cities such Halifax, NS (about 400,000). Coordination in each province is being handled through provincial departments of Environment Canada, although the scope of the work requires the involvement of other provincial government departments, including transportation, agriculture, local government, public safety, natural resources, aquaculture, and tourism.
A good deal of the work involves the accurate identification of areas at risk. In support of this, major investments have been made in gathering high resolution aerial mapping information, employing Light Detection and Ranging (LiDAR) technology, an optical remote sensing technology that measures distance by illuminating the target with light. This laser-based approach enables highly accurate ground and vegetation survey information to be collected. When matched up with locally customised estimates of sea level rise and river flow estimates, it enables flooding scenarios to be examined in great detail. These maps also make it easy to identify and locate critical infrastructure and facilities at risk, for example road links between schools and hospitals and utility hubs.
Existing problems often take on new dimensions when looked at from the point of view of environmental change. For example, one RAC project in New Brunswick is looking at the influence of bank erosion along the upper Saint John River. In some localities, subsiding bank slopes have endangered properties, eventually forcing abandonment. Typical engineering assessments can be applied, but successful adaptation requires the impact of future conditions to be considered as well, such as the increased river flows, more winter flooding and high flow events, more intense flash flood episodes, and more frequent freeze-thaw activity. Accordingly, the recommendations will consider these factors and attempt to build them into ongoing land management and development planning in the region.
Coastal regions in the Atlantic area range from resistant areas featuring hard rock (common around the Bay of Fundy) to areas with softer, more easily eroded sandstones (such as the eastern shore of New Brunswick and all of Prince Edward lsland). There is considerable concern in these communities based on soft geology. Sea level is rising inexorably, coupled with a general slow subsidence of the land as the bulge created by the weight of nearby ice sheets during the last ice age peak settles back. Higher sea levels are expected to be paired with an increased frequency of strong weather systems, which in turn is likely to result in higher storm surges. Diminishing winter sea ice may remove additional protection from erosion from these vulnerable coasts. This poses obvious threats to property, businesses and the coastal way of life. RAC projects are helping provide the basis for improved planning via careful estimation of erosion rates and mapping areas at risk from storm surges.
Coastal flooding and rising sea levels bring another potential threat to coastal communities—the contamination of drinking water supplies by salt water. Locations across the Atlantic region may be affected and some are already having to deal with this problem. This issue was identified for priority attention as part of the RAC. Study locations in each Atlantic province have been selected and are currently involved in field studies.
Mapping the position of salt water underground in aquifers near the coast can be done by a combination of chemical sampling of water from wells and electrical resistance surveys. The University of New Brunswick’s Dr. Kerry McQuarrie and Dr. Karl Butler are studying this issue in Richibucto, a small coastal community on the Northumberland Strait. In the second year of field work, two graduate students are contributing to the study. The outcomes, expected by spring 2012, will be updated groundwater flow models and a detailed insight into sub-surface processes that affect the migration of salt water. Parallel projects are in progress in Prince Edward Island, Nova Scotia and Newfoundland.
Through studying what is causing faster river bank erosion, and providing detailed estimates of sea level rise, temperature, precipitation and groundwater movement, these RAC projects are providing a range of strategic guidance for those who make decisions in municipalities, so they can make better, informed decisions about how to prepare for future changes. So far, the signs are encouraging and there appears to be a willingness to take this kind of information on board and act on it. Nevertheless, a significant challenge can be communicating and explaining the meaning of what can be highly technical information.
In the end, project outcomes must be able to successfully inform decisions about development, construction of new and mending of damaged infrastructure, and emergency planning. Making the adaptation approach work requires extensive networks that bring together people from disciplines who traditionally may have had little to do with each other. And this change is happening in our region. Recent workshops and information sessions have attracted large turnouts with academics, government staff, municipal managers, elected representatives, urban planners, consultants and nongovernmental organizations (NGOs) all taking part. There is a thirst for good guidance and a motivation to act.
Natural Resources Canada coordinates information sharing between the various RAC teams across Canada. Members from all the provinces meet up usually twice per year to take stock of what is working, where the challenges are, and to learn from each regional effort. As the information base of technical guidance grows, the effort is shifting towards broader dissemination of what has been learned to additional communities, and in particular, ways of making sure the latest knowledge is included in planning frameworks and is made available in usable forms.
More information on the Atlantic RAC can be found at:
Information on the national RAC program can be found at:
http://adaptation.nrcan.gc.ca/collab/index_e.php
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