Heat waves across the country could be attributed to climate change

Temperatures in the west, especially in the pacific northwest and western Canada, are at historic highs. Is this a new normal? And if so, how to address this change in the climate. We talked about it with David Hondula, from ASU’s School of geographical sciences and urban planning.

Hondula said that the situation is particularly bad for some communities in the Pacific North-West in the United States and in Canada.

“The event that we saw come through is so extreme that it’s even difficult for the statistical climatologists to put a number on how unlikely this event was,” Hondula said. He added that some of the temperatures seen were 30 degrees warmer than expected averages.

Hondula also said that, with certain climate change attribution studies such as this, it’s difficult to “get a firm handle” on these such events. This is due to their incredibly unusual nature. Because they happen so infrequently, it does make an outright attribution somewhat difficult.

“So, you’re right that the estimates are that this is a one-in-a several thousand-year events, but our historical meteorological record only goes back one hundred years so it’s difficult to say how likely it is to occur in future climate.”

Hondula broke down what specifically could be responsible for such a drastic change in climate, starting with global-scale emissions of greenhouse gasses. Through modelling, scientists found that even in models that include global warming, this amount of temperature increase occurs relatively infrequently.

“This event required a ‘perfect storm’ of other meteorological events to occur,” Hondula said. “The extent to which that process is influenced by global-scale climate change is a little less clear at this time.”

He also said that urbanization is a significant factor in the event. The heatwaves are worse for those living in urban cities that exist with a “heat island” effect in which there is a high amount of heat absorption.