Scientists and policy experts yesterday unveiled San Diego County's first blueprint for adapting to rising sea levels, altered rainfall and other "catastrophic" changes linked to global warming. “A Regional Wake-up Call” offers detailed projections about how the climate will change by 2050 and offers suggestions for how to lessen those effects. “While climate change is a global issue, . . . the San Diego region is uniquely threatened,” says the 177-page report, billed as the first comprehensive assessment of climate change's effects across the region. To date, climate science has focused on understanding long-term weather trends, predicting their worldwide impact and limiting greenhouse gas emissions.