addressing climate change adaptation in regional transportation plans

Addressing Climate Change Adaptation in Regional Transportation PlansA Guide for California MPOs and RTPAsalso the warmest on record, while the combined land and ocean surfacetemperature in the Southern Hemisphere was the sixth warmest such period onrecord. Warming trends over the 20 th century are documented for nearly alllocations that have sufficient data except the North Atlantic Ocean nearGreenland and Iceland, and the Southeast United States.Figure 3.3Observed Global Mean Temperature over Land and OceanSource: NOAA, 2010.The magnitude of the enhanced greenhouse effect is influenced by variouscomplex interactions in the earth-ocean-atmosphere system. Many processesand feedbacks must be accounted for in order to realistically project climatechanges resulting from particular GHG emission scenarios. These complicationsare the source of much of the debate which has occurred about the likelymagnitude and timing of climate changes due to the enhanced GHG effect.3.2 PROJECTED STATEWIDE CONSEQUENCESOF CLIMATE CHANGEFuture projections of climate change for California have been synthesized by the2009 California Climate Change Scenarios Assessment (Cayan et al., 2009), whichexamined changes in average temperatures, precipitation patterns, sea-level rise,and extreme events.TemperatureCalifornia should expect overall hotter conditions by the end of the century. Allmodel projections suggest increased temperatures, with the level of emissionsrepresenting the biggest uncertainty: temperature levels will rise more quicklyand be higher by the end of this century with higher emissions. Based on Cayanet al. (2012), the projections suggest the following:Cambridge Systematics, Inc. 3-3