Typically, this ocean basin spawns some of the most intense tropical cyclones of any place on Earth, though storm activity has been somewhat suppressed so far this year.
The Joint Typhoon Warning Center forecasts Super Typhoon Hagibis (the name means “speed” or “velocity” in Tagalog) to regain Category 5 intensity and maintain that for much of Tuesday, before beginning a slow weakening trend as it curves to the northwest and eventually north, threatening to make a direct hit on Japan this weekend as the equivalent of a Category 1 or 2 storm. The official JTWC forecast calls for the storm to come very close to, if not make landfall on, the heavily populated island of Honshu, which includes Tokyo, by Sunday.
However, track forecasts this far out are fraught with uncertainty, and the JTWC cautions that its forecast has low confidence because of a large spread in projections among the most reliable computer models.
For much of Monday into Monday night, the storm had exhibited a phenomenon associated with some of the most intense and rapidly strengthening storms on record — a pinhole eye. On Tuesday morning, the JTWC measured the eye as just five nautical miles in diameter, but it has expanded as a secondary eyewall has taken over.
This has led to a bizarre sight from space, as the old, tiny eye, complete with its eyewall, spins around within the larger eye as if caught in a meteorological pinball game.
Once Hagibis undergoes a transition to an extra-tropical, or nontropical, low-pressure system northeast of Japan and into the Bering Sea, it will help turbocharge the jet stream blowing at high altitudes from west to east across the North Pacific. Recurving typhoons in the western Pacific are well known for their potential to initiate significant weather pattern changes downstream, thousands of miles away, as the jet stream energy they provide ripples along and forms dips, or troughs, and ridges.
For example, the perturbation to the jet stream may enhance the development of a high-pressure area aloft across the West, potentially bringing a period of warmer-than-average temperatures there.
Global warming may already be contributing to rapid intensification
If it seems as though rapidly intensifying storms such as Super Typhoon Hagibis are occurring more regularly, it’s because they are — at least in some parts of the world. Rapidly intensifying storms are becoming more common in the North Atlantic Ocean Basin, for example. More importantly, such storms are expected to become more frequent worldwide as human-caused global warming continues.
For example, a 2017 paper that studied modeled Atlantic storms showed an uptick in the number of storms that would rapidly intensify just before landfall in a warmer world. Even more alarming was the study’s simulation that storms intensifying by 70 mph or more within 24 hours — which the author, MIT’s Kerry Emanuel, found had occurred on the average of only once per century in the late-20th-century climate — may occur “every 5-10 years by the end of this century.”
Another study, published last year, found that with continued global warming, more tropical cyclones will undergo rapid intensification than had done so before. It also found, using a climate model capable of simulating these massive storms amid changing atmospheric and oceanic conditions, that future storms could be so intense that a new category — Category 6 — might be required to describe their intensity.
For the period between 2016 and 2035, the study found there would be an 11 percent uptick in major tropical cyclones, of Category 3 intensity or greater. It also showed 72 storms with maximum sustained winds above 190 mph by the end of the century, compared with just nine such storms in a simulation of the late-20th-century climate.
Matthew Cappucci contributed to this report.