Heat waves, droughts and floods affect poor people disproportionately, according to a new report that recommends legislation to alleviate the impact as the climate warms.

African Americans living in Los Angeles have a projected heat-wave mortality rate that is nearly twice that of other Los Angeles residents, according to researchers from the University of Southern California and the University of California Berkeley who focused on the growing field of "environmental justice." And Latinos are the primary population in many neighborhoods and regions, including Los Angeles and the San Joaquin Valley, that have the worst air quality in the nation.

The report, "The Climate Gap, Inequalities in how Climate Change hurts Americans and How to Close the Gap" comes as the California Legislature and the U.S. Congress are grappling with how to design systems to control greenhouse gases that trap heat in the atmosphere. And how they are designed will have a major impact on low-income neighborhoods located near refineries, power plants and other industrial facilities that also spew unhealthful conventional pollutants.

"People of color will be hurt the most -- unless elected officials and other policymakers intervene," said Rachel Morello-Frosch, a UC Berkeley researcher.

Next week, the California Assembly is expected to take up a bill, AB 1404, that would drastically limit the amount of greenhouse gases that polluters could offset by paying emitters in other regions to cut their gases. Under loose guidelines adopted by the California Air Resources Board under the state's landmark global warming law, up to 49% of greenhouse gas pollution could be reduced through offsets such as planting trees or capturing landfill gases.