addressing climate change adaptation in regional transportation plans

Addressing Climate Change Adaptation in Regional Transportation PlansA Guide for California MPOs and RTPAs12.2 DEVELOPING ADAPTATION STRATEGIESDetermine Climate Hazard Protection WindowsA limited selection of priority asset/stressor groupings are advanced from therapid assessment described in Module 3 for more rigorous and detailedconsideration in Module 4. At this stage, it is understood that the assetsthemselves are considered critical, often highly critical, and therefore that thepotential consequences of exposure to climate stressors could be significant. It isalso understood that these assets have a substantial future likelihood, perhaps ahigh likelihood, of exposure to one or more climate stressors at thresholds thatmay pose a threat.However, the rapid assessment’s focus is on whether assets and stressorscoincide physically, without necessarily 22 considering temporal concurrence(they overlap in space, but do they overlap in time as well?) or changes in thecondition or characteristics of assets over time. The Climate Hazard ProtectionWindow concept was developed help capture the role of time in determiningexposure. The Window describes the period during which an asset is likely bothto be in service and susceptible to the impacts of one or more climate stressors.The Window opens when a climate hazard first poses significant risk to the assetand closes at the projected end of the asset’s lifespan (with multiple stressorexposures there may be multiple Windows). Understanding of two keytimeframes is therefore necessary to produce a Window (these are described ingreater depth, below):Asset Lifespan and Asset Renewal Cycles. When is the asset due forreplacement? What opportunities for adaptation action might coincide withstandard asset renewal cycles? Advanced assessments may also explore theinteraction between deteriorating asset condition and increased susceptibilityto stressors.Stressor Occurrence. When are stressors likely to begin posing significantrisks to assets due increasing severity (such as exceedance of a hazardthreshold) or frequency? In some instances, the answer may be “today.”22 The previous exposure assessment may include time as an element as well. Forexample, the asset inventory may include future projects from the TIP or LRTP.Hypothetically, where sufficient attribute data is available, even changes in assetcondition based on deterioration curves or asset renewal cycles could be incorporated.Cambridge Systematics, Inc. 12-3