Using machine learning, an international team, including two researchers from the University of Hawai‘i at Mānoa, revealed that human-produced carbon dioxide  emissions and climate change have already caused an increase in day-to-day rainfall fluctuations over the tropical eastern Pacific and the mid-latitudes. Their study was published recently in Nature.

“Climate model projections indicate that warming will intensify rainfall variability and extremes, such as heavy rains and drought conditions, across many regions of the globe,” said Malte Stuecker, study co-author and assistant professor in SOEST Department of Oceanography and the International Pacific Research Center. “However, whether these anthropogenic trends are already visible in present-day rainfall observations has remained a major challenge due to large natural fluctuations in rainfall at regional scales.”

The new study, led by led by Yoo-Geun Ham from Chonnam National University and Seung-Ki Min from Pohang University of Science and Technology, used a deep learning approach to do what machine learning is most adept at doing: process extensive amounts of data and reveal patterns that are difficult for human analysts to decipher. 

The research team devised a deep learning model to quantify the relationship between the intensity of global warming and global daily rainfall patterns from a state-of-the-art climate model. They then applied the deep learning model to data obtained from satellite-based rainfall observations. The results revealed that on more than 50% of all days, there was a clear deviation from natural variability in the daily precipitation pattern since the mid-2010s, influenced by human-induced global warming.  

“Our study demonstrates for the first time that the human fingerprint is already visible in daily rainfall variability in the tropical eastern tropical Pacific and the mid-latitudes, ” said Tim Li, study co-author and SOEST professor. “The increased variability in precipitation due to global warming means that we have a greater risk of heavy rainfall and days without rain in these regions. Associated with this is an increased likelihood of hazards such as flooding, droughts, and wildfires.”

Although the long-term shifts in annual average rainfall remain indiscernible from the natural variability in the eastern tropical Pacific and in the midlatitudes, this study unveils that the impact of global warming on daily fluctuations has already emerged in these regions, including the eastern United States and eastern Canada. 

“There is little doubt that future warming will exacerbate these trends as these are consistent with projections that we showed in our previous work,” said Stuecker. “In addition to reducing CO2 emissions as a mitigation measure, more research is needed to better understand the detailed changes in rainfall extremes on small regional scales – such as here on the islands – to guide local adaptation measures.”

Read more on West Hawai’i Today, The Garden Island, Eurekalert, UH News and Big Island Now.

Imagine being able to go back tens of thousands of years to see how the coral reefs thrived around the Hawaiian Islands, or being able to compare what the climate was like. An international scientific research expedition is setting out to do just that. An international scientific research expedition, carried out on behalf of the International Ocean Discovery Program (IODP) and including local partners at the University of Hawaiʻi and the state, aims to recover a record of past climate and reef conditions off the coast of Hawaiʻi Island. The two-month research expedition will start at the end of August.

Coral reef ecosystems and sea-level change are both impacting the islands, making this research important to everyone in Hawaiʻi. Professor Kenna Rubin, an inorganic geochemist at SOEST’s Department of Earth Sciences, is participating in the expedition.

“These detailed, high-resolution temporal and compositional records anticipated from this expedition will add greatly to our knowledge of past local oceanographic, climate and sea level responses to climate change, as well as helping scientists better understand the volcanic subsidence history of the Big Island,” said Rubin.

Critical piece for future mitigation

The impacts of this research in Hawaiʻi will be adding to existing studies of sea-level change as recorded here by coral reefs, particularly during large fluctuations in sea level that happened during climate instabilities and ice sheet collapses. Such information is a critical piece of future climate-change mitigation and resilience strategies.

Coral reefs are very sensitive to sea level and other changes in environmental conditions. As fossils, they provide a record of past conditions over hundreds, thousands and millions of years of Earth’s history. There is, however, a discontinuity in the global record over the past 500,000 years, especially during periods of major and abrupt climate instability. The IODP Expedition 389 “Hawaiian Drowned Reefs” focuses on this missing link and is led by co-chief scientists: Professor Christina Ravelo, Ocean Sciences Department at the University of California, Santa Cruz; and Professor Jody Webster, School of Geosciences, University of Sydney, Australia.

“The Hawaiʻi fossil reefs are storytellers of the past climate and ocean changes and of the reef ecosystem responses to those changes,” said Ravelo. “We are eager to unlock and share these stories through careful study of the fossils that we hope to recover.”

The expedition aims to recover cores from water depths between 134 and 1,155 meters at a maximum of 20 locations. Even though this will be the first time that a seafloor coring system will be deployed in this area, the anticipated sites are well studied.

“We hope that information recorded in the fossil reefs will help scientists make improved predictions about the rate and magnitude of sea-level rise, what impact global warming and cooling has on short-term climate phenomena like droughts, floods and marine heat waves, and how coral reef ecosystems respond to these changes,” said Webster.

In order to recover the material that scientists will use for their analyses in the coming years, a seafloor corer will be deployed off the multipurpose vessel MMA VALOUR during the expedition. The seafloor corer will be provided and operated by a renowned geotechnical industry specialist, to be lowered to the ocean floor to recover up to 110-meter-long cores beneath the seabed.

Scientists from Australia, Austria, China, Denmark, France, Germany, India, Japan, the Netherlands, Great Britain and the United States will participate in the expedition.

The cores will be archived and made accessible for further scientific research after a one year-moratorium period following the onshore phase of the expedition. All expedition data will be open access and resulting outcomes will be published.

Read also on UH News.

Many oceanic islands that are situated in the middle of tectonic plates undergo “rejuvenated” volcanism following the main building stage. Honolulu features Hawaiʻi’s most recent rejuvenated volcanism, which started around 750 thousand years ago and ended less than 100 thousand years ago. In a recent GSA Bulletin publication, co-authored by Earth Sciences emeritus professor Michael Garcia, a team of researchers present ages and olivine diffusion modeling from Koko Rift lavas to determine when the most recent Honolulu eruptions occurred and to evaluate possible mechanisms of rejuvenated volcanism and volcanic hazards. 

Their investigations of Koko Rift basalts, which includes the famous Hanauma Bay area, suggest that magmas were stored in the crust for many months prior to eruption and that Koko Rift is Hawaiʻi’s youngest known area of rejuvenated volcanism. The timing of Koko Rift eruptions coincides with the pronounced drop in global sea level by over 300 feet (~100 meters). This major sea-level fall may have triggered the eruptions of Koko Rift magmas that were stored in the crust. The proposed mechanism is similar to that at other volcanic islands, which suggests that changes in global sea level may have significant control on the magnitude and frequency of eruptions at ocean island volcanoes. 

Full study available on GSA Bulletin.

NASA has selected the geology team that will develop the surface science plan for the first crewed lunar landing mission in more than 50 years and the team’s lead investigator will be SOEST alumna Brett Denevi, a planetary geologist at the Johns Hopkins University Applied Physics Laboratory. NASA’s Artemis III mission will land astronauts, including the first woman to land on the Moon, near the lunar South Pole to advance scientific discovery and pave the way for long-term lunar exploration.

Read the NASA announcement.

“We are so excited to be representing the lunar science community during this historic mission,” Denevi said. “Our team will focus on maximizing the science that will be accomplished by the Artemis III astronauts — ensuring that the samples and data from the mission enable transformative discoveries for decades to come.”

Denevi completed her doctoral degree in the Department of Earth Sciences (formerly Geology and Geophysics) in 2007 with mentor Paul Lucey, research professor in the Hawai‘i Institute of Geophysics and Planetology. Denevi’s dissertation research focused on understanding the composition of the Moon’s dark, basaltic plains by analyzing the way light is reflected and absorbed by lunar materials.

Another SOEST alumni was also selected to join the Artemis III geology team. Mark Robinson, a professor at Arizona State University, was named as one of the co-investigators in NASA’s announcement. Robinson is the principal investigator of two cameras currently flying in lunar orbit.  The Lunar Reconnaissance Orbiter Camera has been operating since 2009, while ShadowCam went into lunar orbit in December 2022.  Focused on lunar and Martian volcanism, Robinson completed his doctoral degree in Earth Sciences with mentor Pete Mouginis-Mark.

The Artemis III Geology Team will work with NASA to determine the mission’s geological science objectives and plan the Artemis III astronauts’ science activities during their historic moonwalks, which will include field geology traverses, observations, and the collection of lunar samples, imagery, and scientific measurements. 

Of the many potential lines of inquiry for Artemis III to investigate, the team will focus on four: determining the lunar record of inner solar system impact history; understanding the early evolution of the Moon as a model for rocky planet evolution; revealing the age, origin and evolution of volatile materials (such as water ice) in the solar system; and determining the variability of regolith (or surface dust) near the Moon’s poles to understand surface changes on other airless worlds and objects.

“All of these goals have the potential to transform our understanding of the Moon and the cislunar environment,” Denevi said.

“Selecting this team marks an important step in our efforts to optimize the science return of Artemis III,” said Joel Kearns, deputy associate administrator for exploration in NASA’s Science Mission Directorate at NASA Headquarters in Washington. “This team of well-respected lunar scientists has demonstrated experience with science operations, sample analysis, and operational flexibility, all of which is critical for the successful incorporation of science during Artemis III. With the establishment of the Artemis III Geology Team, we are ensuring that NASA will build a strong lunar science program.”

Team members will also evaluate the data returned by the mission, including preliminary examination and cataloging of the first lunar samples collected by NASA since 1972.

“The Artemis III Geology Team will have the unique opportunity to analyze the first-ever samples from the lunar south pole region, helping us not only to unlock new information about the formation of our Solar System, but also with planning for future Artemis missions and establishing a long-term lunar presence,” said Jim Free, Associate Administrator for NASA’s Exploration Systems Mission Directorate.

The collection of samples and data from this region, which contains some of the oldest parts of the Moon, estimated to be at least 3.85 billion years old, will help scientists better understand fundamental planetary processes that operate across the solar system and beyond. The resulting analysis from the geology team’s activities could also help yield important information about the depth, distribution, and composition of ice at the Moon’s South Pole. This information is valuable from both a scientific and a resource perspective because oxygen and hydrogen can be extracted from lunar ice to be used for life support systems and fuel.

Through Artemis, NASA will land the first woman and first person of color on the Moon, establishing a long-term, sustainable lunar presence to explore more of the lunar surface than ever before and prepare for future astronaut missions to Mars.

Portions of this content are courtesy of Johns Hopkins Applied Physics Laboratory and NASA.

The atmospheric flow over the tropical Pacific Ocean, termed the “Pacific Walker Circulation,” is changing, with important implications for El Niño and La Niña events, which bring warmer or cooler water to the eastern tropical Pacific, according to a study published today in Nature by an international team of researchers. As a result of these changes, El Niño and La Niña events that persist for multiple years may become more common, which can exacerbate the associated risks of drought, fire, rains, and floods.

“The tropical Pacific has an outsized influence on global climate,” said Sloan Coats, study co-author and assistant professor in the Department of Earth Sciences in the University of Hawai‘i at Mānoa School of Ocean and Earth Science and Technology.  “Understanding how it responds to volcanic eruptions, anthropogenic aerosols, and greenhouse gas emissions is fundamental to confidently predicting climate variability and projecting future climate in Hawaiʻi and around the globe.”

The team used data from ice cores, trees, lakes, corals, and caves to investigate Pacific Ocean weather and climate over the past 800 years. This allowed them to compare the Pacific Walker Circulation—the atmospheric part of the El Niño Southern Oscillation and a major influence on global weather—before the human-caused rise in greenhouse gases and after. 

“We set out to find out whether greenhouse gases had affected the Pacific Walker Circulation,” said Georgy Falster, lead author of the study and research fellow at the ARC Centre of Excellence for Climate Extremes. “We found that the overall strength hasn’t changed yet, but instead, the year-to-year behavior is different.”

The scientists observed that the length of time for the Pacific Walker Circulation to switch between El Niño-like and La Niña-like phases has slowed over the industrial era.

Volcanoes play a clear role

Volcanic eruptions have the power to impact climate on a global scale, but not every volcano has such impact. Previous research has shown that when there is a strong tropical volcanic eruption, the world tends to get cooler. 

Volcanic eruptions were found to cause an El Niño-like weakening of the Pacific Walker Circulation, according to the researchers’ data analysis and reconstructions of past climate. 

“This is not happening by chance. It’s something that is quite robust,” said co-author Bronwen Konecky, an assistant professor at Washington University in St. Louis. “We see a consistent response in the atmosphere, whereas others have not seen the same response in ocean temperatures. And that’s either because the atmospheric response is stronger or it’s easier to detect.”

“Our study provides a long-term context for a fundamental component of the atmosphere-ocean system in the tropics,” said Coats, whose expertise is Common Era paleoclimate, which focuses on climate variability over the last 2,000 years, and how and why the tropical Pacific is changing with climate change. “Understanding how the Pacific Walker Circulation is affected by climate change will enable communities across the Pacific and beyond to better prepare for the challenges they may face in the coming decades.”

Portions of this content are courtesy of ARC Centre of Excellence for Climate Extremes.

Read also on The Hill, UH News, Science Daily, UC-Santa Barbara News, Washington University News, Courthouse News, Phys.org, West Hawai’i Today, and Maui Now.

Researchers have achieved a breakthrough in the fight to save the world’s coral reefs from climate change annihilation. In a paper published today in Nature Communications, co-authors E. Michael Henley and Mary Hagedorn, research biologists at the University of Hawai‘i at Mānoa’s Hawai‘i Institute of Marine Biology, and collaborators describe the first successful technique for cryopreserving and reviving entire coral fragments. 

This milestone was conducted in Kane‘ohe Bay, Hawai‘i at HIMB and heralds a new age for cryopreservation and coral conservation because the coral fragments contain tens of thousands of cells and are among the most complex biological systems ever successfully ushered through the cryopreservation and thawing process. This proof-of-concept opens the door to collecting and preserving coral fragments easily and rapidly at an urgent moment for coral worldwide.

“This process holds enormous promise to conserve the biodiversity and genetic diversity of coral,” said Hagedorn, who is also a Senior Research Scientist at Smithsonian’s National Zoo and Conservation Biology Institute (NZCBI). “If we can scale this up and refine the post-thaw husbandry, we will be able to work year-round rather than just a few days during spawning seasons. If we can do that, this will be a really viable process that changes how we see the security of corals going forward.”

Recent climate models estimate if greenhouse gas emissions continue unabated, many of the world’s corals could die by the mid-2030s. This leaves precious little time to safeguard their estimated $10 trillion annual economic value or the innumerable other marine species that rely on corals for their livelihood.

Improving cryopreservation methods

Current coral cryopreservation techniques rely largely on freezing sperm and larvae, which can only be collected during fleeting spawning events, which occur only a few days a year for a species. This creates a logistical challenge for researchers and conservationists, and limits the speed with which coral species can be successfully cryo-banked. To complicate matters further, warming oceans and increasingly frequent marine heatwaves mean corals can be biologically stressed such that their reproductive material is too weak to stand up to the rigors of being cryopreserved and thawed.

With these limitations in mind, Hagedorn and her colleagues started their work to cryopreserve and revive entire fragments of coral in 2019. The small fragments of coral used in this study feature about 20 individual coral polyps embedded in a calcium carbonate skeleton. This large mass of tissue with tens of thousands of cells and a skeleton is far more complex to cryopreserve than a single cell, such as a sperm. To get around this problem, Hagedorn and her collaborators focused on a process called isochoric vitrification.

This technique minimizes the toxicity of the cryopreservation solution and prevents the formation of ice by placing the biological material inside a rigid aluminum chamber. When researchers seal the coral fragment inside the solution-filled chamber and rapidly cool it with liquid nitrogen, any water inside tends to not expand and form ice crystals that can damage tissue. If ice starts to form, the unyielding walls of the aluminum chamber restrict its growth. Instead of ice formation, isochoric vitrification preserves the coral polyps in a glass-like state that avoids damage to their delicate cells.

But getting isochoric vitrification to work with corals was not without its challenges. For example, researchers discovered the corals needed to be bleached prior to cryopreservation. In nature, coral bleaching occurs when corals get so stressed — usually from excessive heat —they eject the photosynthetic algae with which they normally have a healthy symbiotic relationship and begin to starve. But during cryopreservation the coral’s symbionts created problems because the symbionts reacted differently to the process than the corals, creating damaging pockets of ice. To bleach the corals prior to cryopreservation, the team used a combination of menthol and intense light. Somewhat counterintuitively, the team noted in the lab the bleached corals appeared quite healthy, possibly because they ingested their damaged symbionts, rather than expelling them.

The research team tested the isochoric vitrification technique with thumbnail-sized fragments of the finger coral (Porites compressa) from Hawai‘i. After vitrifying the bleached coral fragments inside their aluminum chambers by immersing them in a bath of liquid nitrogen, the chambers were warmed, then the fragments were transferred to seawater and allowed to recover. When assessing the health of the revived corals, they found the rate of oxygen consumed by the vitrified-thawed corals was comparable to those that were never cooled. The team stopped their oxygen measurements at 24 hours because of a desire to separate the success of the vitrification process from husbandry issues that will require ongoing refinement.

Now, Henley, also a Research Scientist at NZCBI, and the collaborative team are actively working on the problem of how to keep corals alive beyond 24 hours post-thaw, and the team is exploring the use of antibiotics, antioxidants and probiotics to bolster the corals’ microbiomes and help them survive. 

“Our goal is to cryopreserve as many species of coral as possible by 2030,” said Henley. “If this is successful, we may be able to do that. At a time when climate change is moving so fast, this gives us an amazing ability to stop time here in the 2020s.”

Read also on Popular Science, National Public Radio, UH News, Science Daily, Smithsonian News, Texas A&M News, and Gizmodo.

SOEST alum Patrick Drupp was selected as the director of climate policy and advocacy for Sierra Club, the nation’s oldest and largest grassroots environmental organization. Having worked with Sierra Club since 2019, Drupp will continue his work to advance policy in Congress and the Administration, for example with the Environmental Protection Agency and  Department of Energy, to rapidly deploy clean energy, clean up air pollution, and fight climate change.

Drupp completed his master’s degree in 2010 and doctorate in 2015, both in the Department of Oceanography. Specializing in marine geochemistry, his doctoral research primarily focused on the effects of climate change and ocean acidification on coral reef ecosystems.

Read his career profile in Oceanography Magazine, the official journal of the Oceanography Society.

Drupp spent 2015 as a Sea Grant Knauss Fellow, a marine policy fellowship program that provides a unique educational and professional experience to graduate students who have an interest in ocean, coastal and Great Lakes resources and in the national policy decisions affecting those resources. The program and his placement in the NOAA Office of Education allowed him to expand from the specific focus of his dissertation research topic to a much wider range of work related to oceanography and marine policy.

Soon after assuming his new role with Sierra Club, Drupp was called on to comment on the Environmental Protection Agency’s 2023 announcement that greenhouse emissions had increased 5.5 percent during 2021. He called the report “a sobering reminder that while the U.S. and President Biden have made significant progress against deadly climate pollution, the job is far from finished. … The Biden Administration must use every option available to continue to protect our climate and public health, including equitable and just implementation of the Inflation Reduction Act paired with stronger EPA standards limiting dangerous air and water pollutants.”

Read more on ARCS Honolulu and The Oceanography Magazine

Below is an excerpt from a recently published article in New Scientist magazine:

“For years, climate models have predicted that as greenhouse gas emissions rise, ocean waters will warm. For the most part, they have been correct. Yet in a patch of the Pacific Ocean, the opposite is happening. Stretching west from the coast of Ecuador for thousands of kilometres lies a tentacle of water that has been cooling for the past 30 years. Why is this swathe of the eastern Pacific defying our predictions? Welcome to the mystery of the cold tongue.

This isn’t just an academic puzzle. Pedro DiNezio at the University of Colorado Boulder calls it ‘the most important unanswered question in climate science’. The trouble is that not knowing why this cooling is happening means we also don’t know when it will stop, or whether it will suddenly flip over into warming. This has global implications.”

“SOEST scientists are on the forefront of researching this critical question in climate science and related topics–for example, tropical Pacific climate change in general, El Niño, and Pacific decadal variability,” said Malte Stuecker, assistant professor in the SOEST Department of Oceanography and International Pacific Research Center, who was also featured for the New Scientist article. “For how long the cooling in the eastern Pacific persists and when exactly it will flip to warming will have big implications for regional climate predictions and adaptation efforts – including for Hawaiʻi.” 

To make progress on the cold tongue mystery, Stuecker co-leads an international coordinated working group under the World Climate Research Programme called TROPICS.

Learn more on MSNBC Morning Joe