47 posts tagged with "Climate Change"

Projections of the impacts of climate change on marine ecosystems are a key prerequisite for the planning of adaptation strategies, yet they are inevitably associated with uncertainty. Identifying, quantifying, and communicating this uncertainty is key to both evaluating the risk associated with a projection and building confidence in its robustness. We review how uncertainties in such projections are handled in marine science. We employ an approach developed in climate modelling by breaking uncertainty down into (i) structural (model) uncertainty, (ii) initialization and internal variability uncertainty, (iii) parametric uncertainty, and (iv) scenario uncertainty. For each uncertainty type, we then examine the current state-of-the-art in assessing and quantifying its relative importance. We consider whether the marine scientific community has addressed these types of uncertainty sufficiently and highlight the opportunities and challenges associated with doing a better job. We find that even within a relatively small field such as marine science, there are substantial differences between subdisciplines in the degree of attention given to each type of uncertainty. We find that initialization uncertainty is rarely treated explicitly and reducing this type of uncertainty may deliver gains on the seasonal-to-decadal time-scale. We conclude that all parts of marine science could benefit from a greater exchange of ideas, particularly concerning such a universal problem such as the treatment of uncertainty. Finally, marine science should strive to reach the point where scenario uncertainty is the dominant uncertainty in our projections.

The current and projected impacts of climate change make understanding the environmental and social vulnerability of coastal communities and the planning of adaptations important international goals and national policy initiatives. Yet, coastal communities are concurrently experiencing numerous other social, political, economic, demographic and environmental changes or stressors that also need to be considered and planned for simultaneously to maintain social and environmental sustainability. There are a number of methods and processes that have been used to study vulnerability and identify adaptive response strategies. This paper describes the stages, methods and results of a modified community-based scenario planning process that was used for vulnerability analysis and adaptation planning within the context of multiple interacting stressors in two coastal fishing communities in Thailand. The four stages of community-based scenario planning included: (1) identifying the problem and purpose of scenario planning; (2) exploring the system and types of change; (3) generating possible future scenarios; and (4) proposing and prioritizing adaptations. Results revealed local perspectives on social and environmental change, participant visions for their local community and the environment, and potential actions that will help communities to adapt to the changes that are occurring. Community-based scenario planning proved to have significant potential as an anticipatory action research process for incorporating multiple stressors into vulnerability analysis and adaptation planning. This paper reflects on the process and outcomes to provide insights and suggest changes for future applications of community-based scenario planning that will lead to more effective learning, innovation and action in communities and related social–ecological systems.

Highlights

• Ocean physics and chemistry is being affected significantly by carbon dioxide (CO2) emissions, impacting key  marine and coastal organisms, ecosystems and the services they provide us, including seafood.
• These impacts will occur across all latitudes, including in the waters of British Columbia and Canada. This will have direct impacts on the fish species that are consumed by residents of B.C.
• The supply of B.C.’s “staple seafood” species such as Pacific salmon (e.g., sockeye and chum), Pacific halibut, groundfish species (e.g. sablefish), Pacific hake, crabs and prawns will be affected. This study predicts that by 2050:
  • We could see a 21-per-cent decline in sockeye, a 10-per-cent decline in chum, and a 15-per-cent decline in sablefish stocks.
  • Prices of iconic West Coast species such as sockeye, chum and sablefish are projected to increase by up to $1.33, $0.77 and $0.64 per pound for sockeye, chum and sablefish, respectively, under climate change  scenario alone.
  • Climate change will add pressure on already skyrocketing prices, contributing to an increase of more than 70 per cent in the price per pound in 2015 dollars of B.C.’s iconic species such as sockeye and chum salmon.
• For the 10 staple seafood species of British Columbia, the net change in price attributable to climate change could cost British Columbians up to $110 million a year in 2015 dollars.
• To begin to solve the problem, federal and provincial governments and private actors (businesses, NGOs and individuals) need to work together to make rapid reductions in CO2 emissions and eventually atmospheric CO2 drawdown, and instate other measures to protect ocean health.
• Without action, there will be massive and mostly irreversible impacts of climate change on ocean ecosystems and the fish they provide.

Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people.

With increasing human population, large scale climate changes, and the interaction of multiple stressors, understanding cumulative effects on marine ecosystems is increasingly important. Two major drivers of change in coastal and marine ecosystems are industrial developments with acute impacts on local ecosystems, and global climate change stressors with widespread impacts. We conducted a cumulative effects mapping analysis of the marine waters of British Columbia, Canada, under different scenarios: climate change and planned developments. At the coast-wide scale, climate change drove the largest change in cumulative effects with both widespread impacts and high vulnerability scores. Where the impacts of planned developments occur, planned industrial and pipeline activities had high cumulative effects, but the footprint of these effects was comparatively localized. Nearshore habitats were at greatest risk from planned industrial and pipeline activities; in particular, the impacts of planned pipelines on rocky intertidal habitats were predicted to cause the highest change in cumulative effects. This method of incorporating planned industrial development in cumulative effects mapping allows explicit comparison of different scenarios with the potential to be used in environmental impact assessments at various scales. Its use allows resource managers to consider cumulative effect hotspots when making decisions regarding industrial developments and avoid unacceptable cumulative effects. Management needs to consider both global and local stressors in managing marine ecosystems for the protection of biodiversity and the provisioning of ecosystem services.

The ocean moderates anthropogenic climate change at the cost of profound alterations of its physics, chemistry, ecology, and services. Here, we evaluate and compare the risks of impacts on marine and coastal ecosystems—and the goods and services they provide—for growing cumulative carbon emissions under two contrasting emissions scenarios. The current emissions trajectory would rapidly and significantly alter many ecosystems and the associated services on which humans heavily depend. A reduced emissions scenario—consistent with the Copenhagen Accord’s goal of a global temperature increase of less than 2°C—is much more favorable to the ocean but still substantially alters important marine ecosystems and associated goods and services. The management options to address ocean impacts narrow as the ocean warms and acidifies. Consequently, any new climate regime that fails to minimize ocean impacts would be incomplete and inadequate.

There is an urgent need to increase global renewable energy production as a method of lowering greenhouse gas (GHG) emissions in order to avoid the more devastating effects of climate change and ocean acidification. The latest figures from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), suggest that the international community must reduce anthropogenic GHG emissions by 40 to 70 percent from 2010 levels by 2050, and should aim for near zero emissions by 2100. This would likely keep temperature change below 2°C relative to pre-industrial levels, and would therefore reduce the risk of predicted effects of climate change, such as inland flooding, extreme weather events, food security, and the loss of marine and coastal ecosystems and biodiversity.