Nature World News: The heat is turning up in the Pacific Northwest. Washington and Oregon have been documented undergoing a marked rise in nighttime heat waves.
Nighttime heat waves -- defined by a three-day period where the daily low temperature is in the top one percent of highest temperatures recorded -- have more than quadrupled in the last 30 years, according to researchers at the University of Washington.
According to the researchers, the region west of the Cascades saw only three nighttime heat waves between...