Frequency : Number of heat-wave days in Atlanta cities has doubled the dog days of summer . City dwellers have long endured hot summer afternoons , but the frequency of extremely hot days -- when admissions to hospital emergency rooms for heat-related illnesses spike -- has increased substantially over the past several decades . Raleigh says greenhouse effect , loss of trees and grass in cityscape are to blame . Brian Stone of heat waves in cities a significant public health threat , he writes . He urges planting greenery , making city surfaces reflective , better transit systems .
Frequency : Number of heat-wave days in Atlanta cities has doubled the dog days of summer . Raleigh says greenhouse effect , loss of trees and grass in cityscape are to blame . Brian Stone of heat waves in cities a significant public health threat , he writes . He urges planting greenery , making city surfaces reflective , better transit systems .