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448 assessment of climate change in the southwest united statesTable 19.1 Evolution of knowledge about climate in the Southwest (Continued)2009 Southwest Assessment This Assessment Agreement Evidence Much LessLessSameMoreMuch MoreSameMoreMuch MoreCompeting demands from [Native] treaty rights, rapiddevelopment, and changes in agriculture in the region,exacerbated by years of drought and climate change, have thepotential to spark significant conflict over an already overallocatedand dwindling [water] resource.XXClimate change already appears to be influencing both naturaland managed ecosystems of the Southwest.Future landscape impacts are likely to be substantial, threateningbiodiversity, protected areas, and ranching and agriculturallands.XXXXRecord wildfires are also being driven by rising temperatures andrelated reductions in spring snowpack and soil moisture.How climate change will affect fire in the Southwest variesaccording to location. In general, total area burned is projected toincrease.Fires in wetter, forested areas are expected to increase infrequency, while areas where fire is limited by the availability offine fuels experience decreasesClimate changes could also create subtle shifts in fire behavior,allowing more “runaway fires”—fires that are thought to havebeen brought under control, but then rekindle.XXXXXXXXThe magnitude of fire damages, in terms of economic impactsas well as direct endangerment, also increases as urbandevelopment increasingly impinges on forested areas.XXIncreasing temperatures and shifting precipitation patterns willdrive declines in high-elevation ecosystems such as alpine forestsand tundra.XXAs temperatures rise, some iconic landscapes of the Southwestwill be greatly altered as species shift their ranges northwardand upward to cooler climates, and fires attack unaccustomedecosystems which lack natural defenses.XXIncreased frequency and altered timing of flooding will increaserisks to people, ecosystems, and infrastructure.XX