Plain language summary:

The study found that Arctic warming is contributing to increases in the number of marine heatwaves in the Northeast Pacific over the past few decades. This is due to changes in the atmospheric circulation pattern over the Northeast Pacific, which are reducing the amount of low-level clouds and increasing the amount of solar radiation and reduced latent heat loss. This has resulted in an increase in sea surface temperatures and marine heatwave days. The study suggests that the effects of Arctic warming on marine heatwaves should be taken into account when making climate change adaptation and mitigation plans.