addressing climate change adaptation in regional transportation plans

Adaptation ConsiderationsMany of the stressors already affecting the varied ecosystems in this regionare exacerbated by climate change. These include water management,forest management, fire regimes, agricultural and urban development, coastalmanagement and development, and public health (CDFG, 2007). Changes inthese areas can result in secondary consequences that affect the local economy,public health, and safety.Water ManagementDepending on location, parts of this region are projected to experience between6 inches and 15 inches less rainfall by 2100 (see Table 1). Reduced rainfall,combined with reductions in snowpack and existing diversions, could result in analtered flow regime in the region. This change would be particularly challengingdue to its impact on anadromous fish, such as the coho salmon. Reduced flow,altered timing of flows, and periodic extreme events can result in reduced waterquality, habitat destruction, and/or isolation of habitats. Local jurisdictions shouldcarefully assess local aquatic ecosystems for vulnerability to these changes.Forest Management and Fire RegimesIn 2010, this region was one of the highest timber-producing areas in the state inboth volume and value (BOE, 2010). Humboldt and Mendocino counties are twoof the highest timber-producing counties in California (BOE, 2010).Productivity of forestry operations is likely to be affected by climate changedue to forest growth rates and wildfire vulnerability. While in the short termincreased carbon dioxide concentrations can promote growth, climate changecan affect invasive species, pest populations, and seasonal temperature andmoisture regimes, which, over the long term, can affect productivity of forestryoperations. The northern part of the state is projected to have a greaterincrease in wildfire risk than other parts of the state. This projected increase isbased only on climate (e.g., temperature projections) and does not include anassessment of other factors such as vegetation type or fuel load. In the NorthCoast region, moderate to large increases in large fires (>200 ha) (Westerlinget al., 2009; Westerling and Bryant, 2006) are projected in inland areas. A slightdecrease in wildfire risk along the coast is projected due to changes in vegetativecomposition (Lenihen et al., 2006).Wildfire threatens not only the forestry industry but also the safety of residents.The projected wildfire frequency is a considerable change from currentconditions, meaning communities are less likely to be accustomed to the risks offire and the measures required to address them. Of particular concern for theelderly and children under the age of five (see Table 4) are eye and respiratoryPAGE 17APG: UNDERSTANDING REGIONAL CHARACTERISTICS