Climate change in Canada and in the United States are widely considered to have worsened the heat wave's unprecedented intensity and duration.[1][42][43][44][45][46] According to a preliminary study, which has not yet been peer-reviewed, climate change increased the likelihood of a similar heat wave at least 150-fold.[47][48] While it is yet unknown whether the frequency of these omega blocks is due to global heating,[9] according to the data provided by Verisk, the Pacific Northwest is among the fastest-heating regions in the continental United States and southern Canada.[49] Moreover, the urban heat island effect could have further exacerbated the impact in cities.[50] Based on historic data, several meteorologists noted that this phenomenon should be expected to occur only once over a thousand or several thousand years,[5][47][12] and David Sauchyn, a scientist at the University of Regina, said that climate models had been predicting the heat wave of a similar intensity to happen in late 2020s at the earliest.[52]