Nothing we can really do about this from a public space standpoint, other than planting trees. I'd suggest working on strategies to reduce urban heat island effects, which may include 1) climate change urban planning policies, such as asphalt reduction and PTDM, 2) requirements for "green roofs" and white reflective roofs, 3) improving policies to promote tree planting, bioswales, etc., 4) promotion of alternative transportation modes among others.