PORTLAND, Ore. — Cities from Vancouver south to Eugene hit record temperatures on Wednesday, the day after a July Fourth for the ages. An unofficial accounting of the average global temperature hit a new record high on Tuesday.
Researchers from the University of Maine said that preliminary data showed a global temperature of 62.9 degrees Fahrenheit on July 4. And climate analysts say this "hottest day on record" is no surprise.
“There will be many days in the future that are the hottest day," said Erica Fleishman, executive director of the Oregon Climate Change Research Institute.
Fleishman said that there are a few causes. One is the fact that this year is an example of El Nino, typically a warmer weather pattern. But the main reason, forcing a warming trend for years on end, is global warming.
“Emissions of heat-trapping gases from human activity are making Earth hotter," Fleishman said. "There are these natural climate oscillations regardless, but the overall trend toward hotter temperatures worldwide is virtually a function of human activity.”
Portland hit 96 degrees on Tuesday, its second hottest July 4 on record. But that heat went up a notch Wednesday, with Portland setting a record of 98 for July 5. Vancouver, Eugene, Hillsboro and Troutdale set records as well.
As heat waves become more common, Multnomah County has created a new way to track which neighborhoods are more sensitive to hot weather.
“As you have more concrete, more buildings, less natural vegetation, those areas tend to retain heat more," Fleishman explained.
The county says the heat vulnerability index will be used to determine which areas need more support during hot weather events.