Risk from climate change linked with social factors

Heather Cooley in the Sacramento Bee: Summer brings enjoyment of warm weather, long days, a refreshing swim and barbecues. But it also brings natural hazards. Temperatures in many parts of California are near or exceed 100 degrees. Many cities are also experiencing record high nighttime temperatures, and so the evenings bring little relief from the sweltering daytime heat.

….But while many Californians are exposed to these conditions, some are far more vulnerable than others. Children and the elderly, for example, are more susceptible to heat-related illnesses and other hazards. Or when a fire or flood occurs, those with low incomes may not have the resources to evacuate. They are also often underinsured and unable to rebuild after the disaster strikes.

…Climate risk is a function of our exposure and our vulnerability. Social factors, like age, race and income, are not tied to a specific hazard but will greatly determine the human toll of the hazard and the specific needs for preparedness, response and recovery.

To compare overall social vulnerability – the susceptibility of a given group of people to harm from a hazard – to climate change across the state, the Pacific Institute developed a new "climate vulnerability index" that combines data from 19 different social and economic factors – such as air conditioner ownership, percentage of tree cover, workers in outdoor occupations and more – for each of the state's 7,000 census tracts.

….The greatest risks from climate change are found in areas with both high exposure to a climate impact and high vulnerability. By midcentury, Sacramento is expected to experience up to 31 extreme heat days each summer with temperatures in excess of 102 degrees – conditions that now occur on only the eight hottest days of the year. But while warmer temperatures will affect all Californians, they will be especially problematic for the elderly and others with heightened vulnerabilities, many of whom are concentrated in Southern California and in the San Joaquin Valley….

A 1940 shot by Dorothea Lange of a squatter's camp near Sacramento