The Jet Star roller coaster, from the superstorm Sandy-wrecked Casino Pier in Seaside Heights, on Oct. 31, 2012 (file photo by Doug Hood/Staff Photographer)
Watch out Jersey Shore, back bays and other coastal areas.
Climate change is expected to have profound impacts – including sea level rise, storm surges, coastal flooding, erosion and ocean acidification – in coastal locales, according to an international climate report released today.
Here are edited excerpts from the Intergovernmental Panel on Climate Change report’s chapter on coastal systems and low-lying areas (the passages in bold are my emphases):
– Coastal systems are especially sensitive to three key drivers related to climate change: sea level, ocean temperature and ocean acidity (very high confidence).
Boats in Mantoloking after Sandy (file photo by Peter Ackerman/Staff Photographer)
– Coastal systems and low-lying areas will increasingly experience adverse impacts such as submergence, coastal flooding and coastal erosion due to relative sea level rise (very high confidence). Eroding beaches, sand dunes and cliffs will continue eroding as the sea level rises (high confidence). Storm-related impacts and storm surges will be worsened by global sea level rise. Relative sea level rise and impacts are influenced by a variety of local processes unrelated to climate, such as land subsidence, glacial isostatic adjustment, sediment transport, coastal development) (very high confidence).
– Acidification and warming of coastal waters will continue with significant negative consequences for coastal ecosystems (high confidence). The increase in acidity will be higher in areas where eutrophication or coastal upwellings are an issue. It will have negative impacts for many calcifying organisms (high confidence). Warming and acidification will lead to coral bleaching, mortality and decreased constructional ability (high confidence), making coral reefs the most vulnerable marine ecosystem with little scope for adaptation. Temperate seagrass and kelp ecosystems will decline with the increased frequency of heat waves and sea temperature extremes as well as through the impact of invasive subtropical species (high confidence).
– The population and assets exposed to coastal risks as well as human pressures on coastal ecosystems will increase significantly in the coming decades due to population growth, economic development and urbanization (high confidence). The exposure of people and assets to coastal risks has been rapidly growing and this trend is expected to continue. Humans have been the primary drivers of changes in coastal aquifers, lagoons, estuaries, deltas and wetlands (very high confidence) and are expected to further exacerbate human pressures on coastal ecosystems resulting from excess nutrient inputs, changes in runoff and reduced sediment delivery (high confidence).
A home in Mantoloking following Sandy (file photo by Peter Ackerman/Staff Photographer)
– For the 21st century, the benefits of protecting against increased coastal flooding and land loss due to submergence and erosion at the global scale are larger than the social and economic costs of inaction (high agreement, limited evidence). Without adaptation, hundreds of millions of people will be affected by coastal flooding and will be displaced due to land loss by year 2100; the majority of those affected are from East, Southeast and South Asia (high confidence). At the same time, protecting against flooding and erosion is considered economically rational for most developed coastlines in many countries under all socioeconomic and sea level rise scenarios analyzed, including for a 21st century global average sea level rise of more than 1 meter (3.3 feet) (high agreement, low evidence).
– The relative costs of adaptation vary strongly between and within regions and countries for the 21st century (high confidence). Some low-lying developing countries (e.g. Bangladesh, Vietnam) and small island states are expected to face very high impacts and associated annual damage and adaptation costs of several percentage points of GDP. Developing countries and small island states within the tropics dependent on coastal tourism will be impacted directly not only by future sea level rise and associated extremes but also by coral bleaching and ocean acidification and associated reductions in tourist arrivals (high confidence).
– The analysis and implementation of coastal adaptation have progressed more significantly in developed countries than in developing countries towards climate resilient and sustainable coasts (high confidence). Given ample adaptation options, more proactive responses can be made and based on technological, policy-related, financial and institutional support. Observed successful adaptations include major projects (e.g. Thames Estuary, Venice Lagoon, Delta Works) and specific practices in both developed countries (e.g. Netherlands, Australia) and developing countries (e.g. Bangladesh). More countries and communities carry out coastal adaptation measures including those based on integrated coastal zone management, local communities, ecosystems and disaster reduction, and these measures are mainstreamed into relevant strategies and management plans (high confidence).
