Introduction to Climate Change
The International Panel on Climate Change (IPCC) Fourth Assessment Report: published in 2007 stated:
"Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities since 1750 and now far exceed pre-industrial values determined from ice cores spanning many thousands of years. The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land use change, while those of methane and nitrous oxide are primarily due to agriculture."
The improved scientific understanding of the anthropogenic influences on warming and cooling of the climate has led to a high level of confidence that the global average net affect since 1750 has been one of warming.
Evidence of a warming climate is observed in the increase in global average air and ocean temperatures, the widespread melting of snow and ice and rising global average sea-level.
Based upon the IPCC Special Report on Emissions Scenarios the following phenomena and future trends are projected:
- Warmer and fewer cold days and nights over most land areas (virtually certain);
- Warmer and more frequent hot days and nights over most land areas (virtually certain);
- Warm spells/heat waves. Frequency increases over most land areas (very likely);
- Heavy precipitation events. Frequency (or proportion of total rainfall from heavy falls) increases over most areas (very likely);
- Area affected by droughts increases (likely);
- Intense tropical cyclone activity increases (likely);
- Increased incidence of extreme high sea level excluding tsunamis (likely);
From Impacts to Adaptation: Canada in a Changing Climate 2007 (http://adaptation.nrcan.gc.ca/assess/2007/index_e.php) published by the Government of Canada in 2008 presented the following key findings for Atlantic Canada:
Atlantic Canada will experience more storm events, increasing storm intensity, rising sea level, storm surges, coastal erosion and flooding. Coastal communities and their infrastructure and industries, including fisheries and tourism, are vulnerable to these changes. Impacts on coastal infrastructure, such as bridges, roads and energy facilities, have already affected trade and tourism in the region, and some coastal communities have started experiencing saltwater intrusion in their groundwater supply. Future disruptions to transportation, electricity transmission and communications will have widespread implications, including increasing the susceptibility of some communities to isolation.
Water resources will come under pressure as conditions shift and needs change. Seasonal and yearly variations in precipitation will combine with higher evapotranspiration to induce drier summer conditions, especially in Maritime Canada. Limited water resources would affect municipal water supplies and challenge a range of sectors, including agriculture, fisheries, tourism and energy.
For marine fisheries, impacts will extend beyond fish species to include numerous aspects of fishery operations, including transportation, marketing, occupational health and safety, and community health. Harvesters of wild marine resources are constrained in their potential responses to climate change by the existing regulatory regimes. Integration of climate change into assessments and policy development would allow more effective management of marine resources.
Although higher temperatures and longer growing seasons could benefit agriculture and forestry, associated increases in disturbances and moisture stress pose concerns. Changes in climate have implications for management of agricultural production and farm water usage. Re-examination of cropping systems and improved water management would help the agricultural sector to adapt, although non-climatic factors, such as socioeconomic and demographic trends, may limit adaptive responses. In some areas of the Maritimes, forested areas will be affected by drier summers, potentially leading to reduction or loss of species that prefer cooler and wetter climates. Options for short-term adaptation, although limited in the forestry sector, are likely to focus on minimizing other stresses and preserving genetic diversity.
Vulnerability to climate change in the Atlantic region can be reduced through adaptation efforts focused on limiting exposure and through careful planning. Identifying vulnerable infrastructure, incorporating river and coastal flooding in land-use policies, revising emergency response measures, and accounting for sea-level rise when planning and building infrastructure would reduce damage to infrastructure and the environment, and lessen the risk to human health and well-being. Other effective adaptation measures include managing development in coastal areas, preventing construction in areas of known vulnerability, and protecting coastlines around significant sites. In some communities, low adaptive capacity due to aging populations and average annual incomes lower than the national average will make adaptation challenging to implement.
Last Updated on Sunday, 28 October 2012 22:50