By Georgina Wade
Hurricane Lane may have passed by the volcanic archipelago over the weekend, but Hawai’i is still feeling the storm’s after effects as residents recover from days of heavy rain and remain on the lookout for even more showers.
Excessive rainfall triggered flash flooding, raging surf, as well as land and mudslides. On the island of Maui, a giant sinkhole opened in the middle of a road, uprooting trees, inundating drainage systems and causing some residents to remain stranded.
Dropping 52.02 inches of rain (about 132 cm) over a five-day period, Hurricane Lane has broken the Hawai’i tropical cyclone storm total rainfall record, previously set by Hurricane Hiki in 1950 at 52 inches. Although the figure is preliminary, forecasters are classifying Lane as the second-wettest tropical storm in the United States since 1950 following the record set by Hurricane Harvey in 2017.
Hurricanes seldom get close to Hawai’i and it’s even more of a rarity for a Category 5 to get in such close proximity of the islands. Hurricane Lane is the second Category 5 hurricane on record to pass within 350 miles or less of South Point, Hawai’i. The only other storm to do that was Hurricane John in 1994. Only two direct hurricane landfalls have been recorded, both on the island Kaua’i: Category 1 Dot in 1959 and Category 4 Iniki in 1992, which caused $3 billion in damage.
Typically, hurricanes weaken long before they approach Hawai’i due to a ring of deep, cool water that essentially surrounds the archipelago. As hurricanes are fuelled by warmer ocean temperatures, cool waters surrounding the islands usually serve as a protective barrier against ocean storms. Wind currents will also typically steer eastern-Pacific hurricanes back to the coast before they can make it to the central Pacific. This year, weaker than normal winds are allowing storms to stay alive.
This summer has been one of record-breaking temperatures, resulting in abnormally high water temperatures for the area. Sitting at about 1 to 2 degrees Celsius warmer than normal, the warmer water served as the perfect fuel for a hurricane.
Research published in Nature Climate Change in 2015 found that warmer ocean temperatures, caused by climate change, may be fuelling stronger hurricanes while, at the same time, creating fewer storms. The study found from 1984 to 2012, wind speeds in tropical cyclones increased by 1.3 m/s. During that same time period, there were 6.1 fewer storms than would be expected if ocean and land temperatures had not increased.
National Oceanic Atmospheric Administration (NOAA) climate scientists who studied the 2014 hurricane season around Hawai’i found it was made “substantially more likely” by climate change caused by greenhouse gas emissions, with a natural boost from El Niño. Additionally, a study conducted by NOAA last year connected global warming to 2015’s record number of major storms in the region, including three Category 4 hurricanes in the central and eastern Pacific at the same time.
Although many climate studies are predicting that as the world warms, the globe overall and the Atlantic region will likely have fewer named storms, these can be expected to be more intense than normal. However, the central Pacific forgoes that prediction as storms that should be deemed as unusual for the region, are soon to become more common.