An emergency room doctor has devised a scientific index to predict the likelihood that illegal immigrants will die while walking through the Arizona desert during extreme heat. The probability of death reaches 50 percent when temperatures climb to 104 degrees (40 degrees Celsius) or higher, Dr. Samuel Keim concluded. He hopes to begin issuing daily forecasts by May, according to AP. «It's like a weather forecast,» said the Rev. Robin Hoover, whose Humane Borders group maintains water stations for immigrants at desert sites in southern Arizona and northern Mexico. «If he can forecast it to the U.S. Border Patrol, more of their agents can be scattered out looking for people in trouble.» Keim said he has not determined how to disseminate the information and with whom to share it. «We're still negotiating that with various different entities,» he said, declining to give specifics because of worries that the intense political debate surrounding illegal immigration in the United States could scare off potential participants. Deaths of migrants on the Arizona-Mexico border have soared in recent years as tighter border security sends people to more remote desert areas. Some migrants cross 50 miles (80.5 kilometers) or more of desert before reaching a pickup point. In July 2005, Border Patrol agents recovered 72 dead illegal immigrants in the agency's Tucson sector. Nearly all perished from heat exposure. Ron Bellavia, commander of the U.S. Border Patrol's rescue operations in the Tucson area, said an index such as Keim's «would be an appropriate measure to probably reduce exposure or environmental injuries.» The forecasts could also be shared with groups near northern Mexican migrant-staging areas, where the warnings could be posted, Hoover said. For years, the Border Patrol and the Mexican government have issued announcements about the desert's heat-related perils, but Keim said he does not know whether migrants read or heed them. Keim matched heatstroke victims with dates of death and desert temperatures using data collected between 2002 and 2006 by the medical examiner's office in Pima County.
