Table 2.

Examples of anticipated changes to the distribution, likelihood, and magnitude of hazardous substance releases and spills associated with global climate change

Nature of threat	Geographic region	Likelihood	Net impact	Potential magnitude of impact	Relation to global climate change	Comments	Reference(s)
Trans-Arctic shipping	Arctic	High	Increase	High—shallow water, sensitive species, significant spill response challenges	Seasonal reductions in Arctic ice cover open new shipping lanes	Northern sea route (NSR) 35–60% shorter than Suez or Panama Canal from northern Europe to Asia	11–13
Decreased shipping outside Arctic	Temperate and tropic areas	High	Decrease	Low—relative to total global vessel traffic	Reduced sea ice opening Arctic sea to shipping	Expect increased Arctic shipping to reduce traffic on existing routes
Oil and mineral exploration and development	Arctic coastal and offshore	High	Increase	High	Consequence of seasonal sea-ice reductions	Arctic rich in coal and mineral deposits; oil/gas shipments via NSR projected to be 40 MT/year by 2020	11, 12, 60
Oil and mineral exploration and development	Arctic inland	High	Decrease	Locally high	Shorter ice road season limits land-based development	Shorter ice road season may make production difficult or uneconomical	11, 60
Erosion	Arctic watercourses and coastal	Occurring	Increase	Locally high—Threatens existing fuel storage infrastructure, landfills, contaminated sites, drilling mud pits	From increased storm energy, coastal rain, tidal surge, and sea-level rise; reductions in permafrost (soil stability)	Average observed erosion rates at some locations equal or exceed 5 meters/year	11, 13
Permafrost melt	Arctic	Occurring	Increase	Locally high—Releases from waste-disposal sites, sewage lagoons, landfills; increased spill risk	Melting releases contaminants “contained” by ice; threat to cities, ports, and pipeline systems (especially Russia)	Northern pipelines and oil infrastructure may experience frost heave, thaw settlement; in discontinuous permafrost slope stability may be affected	13, 14, 60, 61
Increase in category 4 and 5 hurricane frequency; large-magnitude cyclones	Temperate and tropics	High	Increase	High—Hurricane Katrina: release of millions of gallons of oil; hundreds of hazardous materials releases reported	Warmer ocean resulting in longer storm life and/or greater intensity	Observed increase in proportion of category 4 and 5 hurricanes over 30-year period: modeling suggests warming may increase tropical cyclone destructiveness	15–17
Increased intensity and frequency of heavy precipitation events	Tropics and high latitudes	High	Increase	Locally high—Flooding may threaten infrastructure	Sediment scour/deposition decreases reservoir life span, amplifying flood risks, possibly increasing risk of dam failure	Threatened infrastructure includes pipelines, oil and chemical storage sites, industrial facilities, wastewater-treatment plants, and hazardous waste sites	62–64
Decreased precipitation amount and/or seasonality	Temperate and arid areas	High	Decrease	Locally moderate to high	Reduced flood risk in drought areas	Uncertainty: arid areas may, however, experience flash flooding
Sea-level rise	Global: low-lying coastal areas	High	Increase	Locally moderate to high	While uncertainty exists, most sea-level modeling scenarios project increases	Sea-level rise may inundate coastal contaminated sites, increasing risk to aquatic resources	62
Increased number and intensity of wildfires	Western United States, northern boreal forests, Australia	Occurring	Increase	Locally moderate	Wildfire incidence and/or intensity projected (or currently observed) to increase in some regions.	Fires could potentially threaten oil and gas infrastructure, contaminated sites, and/or hazardous waste-storage sites, increasing spill risk	18, 65, 66