Extreme Fire, Drought And Heat Seem To Be Tied To "Stuck" Jet Stream - a.k.a. 7-Wave Pattern
During the summer of 2018, the future of climate change became the present. Highly amplified jet stream patterns remained stuck in place for unusually long periods of time, bringing the planet an onslaught of remarkable weather catastrophesfor example, unprecedented heat waves and drought in East Asia and Northern Europe, the start of the deadliest and most expensive fire season on record in California, and Japans deadliest floods since 1982.
The extreme summer weather helped bring the 2018 tally of billion-dollar weather-related disasters to 39the fourth highest such total for any year since 1990, according to insurance broker Aon Benfield. Among these were seven billion-dollar droughtsthe highest number of billion-dollar droughts on record (previous record: six in 1999 and 2015). Total damages from drought in 2018 were near $33 billiontied for the fifth-highest level of global drought damage since 1975.
Unfortunately, extreme jet stream patterns like those of 2018 may be getting more common and more extreme, representing a significant danger to global food security. An April 26 paper, Extreme weather events in early summer 2018 connected by a recurrent hemispheric wave-7 pattern, by climate scientist Kai Kornhuber of Columbia University and co-authors, found that the 2018 extremes were associated with a particular mode of stuck in place jet stream behaviorone that has increased in frequency and persistence in recent decades.
A just-published December 9 follow-up study, Amplified Rossby waves enhance risk of concurrent heatwaves in major breadbasket regionsalso led by Dr. Kornhuberfound that stuck jet stream patterns like seen in 2018 are prone to bringing simultaneous heat waves and associated drought conditions to multiple important grain-producing regions of the world. The authors wrote that these stuck jet stream patterns can cause reductions of 4% in crop production in the affected regions, with regional decreases up to 11%. Given the importance of these regions for global food production, the identified teleconnections have the potential to fuel multiple harvest failures posing risks to global food security. (A teleconnection is a causal connection or correlation between meteorological phenomena which occur a long distance apart).
EDIT
https://climatecrocks.com/2022/06/15/concerning-pattern-sets-up-in-jet-stream/