Appendix 5
Reference Document 5-3
Climate Impacts to North Carolina’s Mountain Habitats and Species
Increased air and water temperatures, and the loss of wintery conditions Air temperatures
North Carolina’s mountain habitats are known for generally being cooler than surrounding lower elevations in the region, with average temperature about 10° F cooler. However, mountainous regions in particular are expected to experience significant warming this century with major anticipated effects on biodiversity (MRI 2015) . Previous studies have shown that air temperatures in the mid- and south-Atlantic region of the United States (US), that includes the central Appalachian region, have increased between 0.9 and 3.4 °F on average compared to historical temperatures (Patterson et al. 2012; Pitchford et al. 2012) . The Blue Ridge Ecoregion of North Carolina is projected to experience 3 additional days per year that reach 95 °F (i.e., the number of days that have maximum temperatures ≥95 °F) by 2050 and 5 to 11 additional days by 2075, depending on emission scenario. These projected increases are substantial considering the Blue Ridge Ecoregion of North Carolina typically experiences less than one day at or above 95 °F, which represents a 650% increase by 2050 and a 1540-3070% increase by 2075 compared to historical numbers. Table 11, Appendix 5 Reference Document 5-2, provides a summary of this information. Exhibiting the greatest topographic relief and complex terrain in the eastern US, the southern Appalachian Mountains (SAM) contain some of the most diverse biological and climatological environments in the country. As a result, the rate and magnitude of climate impacts at high elevations compared to nearly blower-elevation sites within the SAM has been found to differ in several studies (Nogués-Bravo et al. 2007; Pepin and Lundquist 2009; Fridley 2009) . Temperatures also differ significantly between closed-canopy and open-site locations in the SAM, with forest-floor temperatures generally being cooler in the day and warmer at night than open sites, meaning wildlife in forest environments will experience significantly different environmental conditions than those that occupy open sites (Morecorft et al. 1998; Friedland et al. 2004; Fridley 2009; Lesser and Fridley 2015) .This means complex relationships exist between the extent of warming temperatures, elevation and topography within the SAM (Beniston 2003; Lesser and Fridley 2015) . Indeed, a landscape- scale analysis showed that rates of change for maximum seasonal temperatures, frost-free days, and growing degree days in the SAM were strongly determined by their topographic position: high-elevation ridges had greater rates of maximum temperature increases, whereas high-elevation near-stream positions showed the least amounts of increases in these metrics (Lesser and Fridley 2015) . Therefore, organisms that rely on growing season length may experience the largest climate effects at lower elevations, while those that depend on warm days in spring and autumn for particular life-cycle processes will experience the largest shifts at high-elevation ridges (Lesser and Fridley 2015) .
2025 NC Wildlife Action Plan
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