Exceptional climate regimes require a close review as to their catalyst to understand how the pattern developed to help mitigate risk, if possible, to similar future circumstances. The record-strength Canadian fire season of 2023 (so far) was caused by a set of unique circumstances all occurring at once to promote a flash fire acceleration during mid-to-late spring 2023.

Marine heat waves (MHW’s) and oceanic warm holes are not new. However, their presence, intensity, and persistence has intensified during the past 10 years. Currently, Climate Impact Company (and other government/research centers in the U.S. and New Zealand) are monitoring 5 MHWs.

A semi-permanent upper-level high-pressure ridge formed in the Northeast Pacific Ocean and extended to Western North America centered on the 2013-16 period. The upper ridge was well-correlated to the “warm blob” of surface and deep layer ocean water in the Northeast Pacific at that time. The “warm blob” was an example of a marine heat wave (MHW) and the attendant upper air pattern became known as the “ridiculously resilient ridge” (RRR) infamous for accelerating the long-term California drought.