Presenter: Yuqing Wang, Professor, UHM Dept. of Atmospheric Sciences and IPRC
Title: Why is the Progress in Improving Tropical Cyclone Intensity Forecast So Slow, and Any Hope?
Please bring a mug and join us for coffee, tea, and cookies, MSB courtyard, 3:00 p.m.
Welcome to “808 Weather with Cruz and Nuge,” a new monthly web series that looks at fascinating weather phenomena in Hawai‘i.
From hurricanes to the “green flash,” KHON2’s Justin Cruz and Dr. Alison Nugent, assistant professor of Atmospheric Sciences, will break it all down with a fun twist on science. Episode One focuses on hurricane season and why hurricane season runs from June through November.
Watch Episode One at KNON2.
Presenter: Licheng Geng, Graduate Assistant, UHM Dept. of Atmospheric Sciences
Title: Eddy-Driven Jet in the Future Climate–A Revisit in Idealized Simulations
Please bring a mug and join us for coffee, tea, and cookies, MSB courtyard, 3:00 p.m.
Presenter: Steven Businger, Professor and Department Chair, UHM Dept. of
Title: On the Need to Improve Arctic Weather and Ice Extent Prediction in a Warming World
Please bring a cup and join us for coffee, tea, and cookies, MSB lanai, 3:00 p.m.
Hawai‘i will be under increasing risk of flooding and other damaging storm impacts as climate change shifts the historical pattern of hurricane tracks and raises the ocean level to make the islands more vulnerable, according to a study led by researchers at the Department of Ocean and Resources Engineering (ORE) .
A team of researchers, led by professor Kwok Fai Cheung and lead author Ning Li, mapped future hurricane flooding from storm surge and waves on top of the projected sea level rise. While the study didn’t find a significant increase in the number of cyclones, the data did show that hurricanes that historically pass to the south of the islands will instead approach closer to Hawai‘i with more landfalls.
The maps show substantial hurricane flooding across large sections of O‘ahu’s South Shore, including parts of Waikiki, Kaka‘ako, Honolulu Harbor and downtown, and Daniel K. Inouye International Airport. “Most of the flooding in Waikiki does not come directly from the ocean, but via the Ala Wai Canal,” Cheung said.
Historically, tropical cyclones traveling from the Eastern Pacific to the Central Pacific weaken and move to the south when approaching the Hawaiian Islands due to a high- pressure system to the northeast, strong wind shear and relatively cool waters. But this study indicates those conditions are unlikely to be prevalent toward the end of the century.
“Nowadays they all seem to be moving closer to the islands,” said Cheung, who has lived in Hawai‘i for 25 years. “In the last few years, we’ve had several major storm events approaching the Hawaiian Islands from the east, so we already feel a change in the pattern.”
Cheung said Hawaii may have gotten a glimpse of the future in 2015, when powerful El Niño conditions warmed ocean waters around the islands and helped to fuel 15 cyclones in the Central Pacific — roughly triple the basin’s average. The study joins a growing body of scientific evidence suggesting that climate change will bring greater impacts from hurricanes in the coming decades.
Read more about it in the Honolulu Star-Advertiser, the Hawaii Tribune-Herald, Big Island Now, Honolulu Magazine, and UH News. Watch the video report and read more about it at KHON2.
As of 22 October 2018, the eastern Pacific Ocean recorded its most energetic cyclone season on record. That assessment comes from Phil Klotzbach, now at Colorado State University in Fort Collins. There, he analyzes tropical storms and hurricanes, calculating how much energy they release. That energy is expressed as a numerical score known as Accumulated Cyclone Energy (ACE). These scores have been kept since around 1970.
Hawai‘i may find itself pummeled by hurricanes even more in coming years. The reason is climate change, according to scientists at the Department of Atmospheric Sciences (ATMO) and the International Pacific Research Center (IPRC). Professor Bin Wang warns that his team’s models indicate “a substantial increase in the likelihood of tropical cyclone frequency … with a northwestward shifting of the tropical cyclone track.” That would put the southern Hawaiian islands directly in a path that future storms are more likely to take.
Read more about it in the young reader-friendly Science News for Students.
The region known as the U.S.-affiliated Pacific Islands is no stranger to variable weather and climate. One of its dominant weather influencers is the El Niño-Southern Oscillation (ENSO), an alternating pattern of abnormally warm and cool ocean temperatures in the tropical Pacific. ENSO can cause drought-like conditions in the southwest Pacific that persist for 3–4 seasons, as well as frequent cyclones and storms.
Given the region’s regular bombardment of extreme events, U.S.-affiliated Pacific Islands decision-makers need accurate predictions from climate models. However, modeling errors can limit the reliability of forecasts.
Now, a researcher from the International Pacific Research Center (IPRC) is leading a project to identify those errors. Supported by a $508,000 grant from the NOAA Research Modeling, Analysis, Predictions and Projections (MAPP) Program, Senior Researcher H. Annamalai and his team will develop tools, known as diagnostics, to pinpoint where and how errors begin, to help scientists determine how to improve their models.
Read more about it in the UH System News and The Garden Island; see also the IPRC press release.
Presenter: Ingo Richter, Senior Scientist, JAMSTEC
Title: On the Predictability of the Equatorial Atlantic
2018 has been a very active hurricane season so far — and it’s only September. On Saturday, Olivia is forecast to be the fifth hurricane to enter the Central Pacific this hurricane season. And there’s even more activity behind it. Climate experts expect to see activity for a couple more months and there are several reasons why. They say because of global warming and higher water temperatures farther north, along with signs of El Niño, hurricanes are now following a new and more menacing route.
“In other words, the major hurricane track, currently, is basically confined to the south of the Hawaiian Islands. But with the global warming, this track may be projected to shift northward,” or closer to Hawaii, said Pao-Shin Chu, professor of Atmospheric Sciences and Hawai‘i state climatologist.
Read more and watch the video report at Hawaii News Now.
For information on Hurricane Olivia, read and watch interviews with Alison Nugent, an assistant professor in Atmospheric Sciences, at KHON2 here and an update here, or read advice on hurricane preparations on Jetty.
For a discussion between KHON2 weather anchor and Nugent related to tropical cyclones around the world, visit here and here.
First there was Hector, followed by Lane. Next it was Miriam, with Norman on her heels. Olivia is on the horizon and appearing to threaten the islands next week. It’s been a busy month for the Central Pacific Hurricane Center, which since Aug. 6 has tracked three major hurricanes (Category 3 to 5) and another that reached Category 2 status.
With signs of a developing El Niño, it’s possible the parade of tropical cyclones marching across the Pacific will continue for the next couple of months and maybe even late into the hurricane season.
But one hurricane expert says we might be in for a break after Olivia passes — at least for a few weeks. “Sub-seasonal variability should be working to suppress hurricane activity in your part of the world for the next couple of weeks,” Colorado State University hurricane researcher Phil Klotzbach said Thursday.
Why has the past month been so busy for tropical cyclone activity in the Pacific? One reason is warmer- than-normal sea surface temperatures. “They’ve been really, really warm in the tropical belt of the North East Pacific and the Central Pacific,” said Pao-Shin Chu, professor of Atmospheric Sciences and Hawai‘i state climatologist.
Strong southwesterly wind shear — the changing direction of the wind’s speed or direction aloft over a short distance within the atmosphere — was credited for slowing down powerful Hurricane Lane and then tearing it apart before it had a chance to unleash its power on O‘ahu. “By and large, most hurricanes approaching Hawai‘i in the Central Pacific end up weakening because of wind shear,” said Steven Businger, professor and chairman of the Department of Atmospheric Sciences.
Read more about it in the Honolulu Star-Advertiser (subscription required).
