The Hawaiian Islands are renowned for their breathtaking natural beauty, but beneath the surface lies a crisis that threatens the very existence of these iconic ecosystems. As our planet absorbs increasing amounts of carbon dioxide from the atmosphere, oceans around the world, including those surrounding Hawaii, are becoming more acidic. A recent study by researchers at the University of Hawai’i at Mānoa has revealed that unprecedented levels of ocean acidification are expected to hit Hawaiian waters within the next three decades.

This alarming trend poses a significant threat to marine life, particularly corals and clams, whose shells and skeletons will weaken under the increasing acidity. The consequences will be far-reaching, as these ecosystems support an array of species and play a vital role in maintaining ocean health. However, there is hope – some organisms have demonstrated their ability to adapt to changing waters.

Researchers, led by Professor Brian Powell from the Department of Oceanography at UH Mānoa’s School of Ocean and Earth Science and Technology (SOEST), employed advanced computer models to project how ocean chemistry around Hawaii might change over the 21st century under different climate scenarios. The results are stark: even in a low-emission scenario, where carbon emissions flatline by mid-century, ocean acidification will increase significantly in surface waters around the main Hawaiian Islands.

The extent and timing of these changes vary depending on the amount of carbon added to the atmosphere. In a high-emission scenario, the team found that ocean chemistry will become dramatically different from what corals have experienced historically, potentially posing significant challenges to their ability to adapt. Even in this scenario, some changes are inevitable, but they occur more gradually.

The researchers calculated the difference between projected ocean acidification and acidification that corals in a given location have experienced in recent history. They referred to this as ‘novelty’ and discovered that various areas of the Hawaiian Islands may experience acidification differently. Windward coastlines consistently exhibited higher novelty, meaning future conditions will deviate more dramatically from what coral reefs have experienced in recent history.

The study’s findings serve as a wake-up call for researchers, conservationists, policymakers, and the public to take immediate action. By understanding the future challenges facing Hawaiian coral reefs, we can work towards preserving these critical ecosystems for future generations.

As Dr. Powell emphasizes, “This study is a big first step to examine the totality of changes that will impact corals and other marine organisms and how it varies around the islands.” The research team will continue to investigate the future changes in Hawaiian waters, specifically heat stress, locations of possible refugia for coral reefs, and changes to Hawai’i’s fisheries.

Unveiling 12,000 Years of European History: The Mont Blanc Ice Core Record

A team of researchers from the Desert Research Institute’s (DRI) Ice Core Lab has made a groundbreaking discovery by analyzing a 40-meter long ice core from the French Alps. This study, published in the June issue of PNAS Nexus, reveals an intact record of atmospheric aerosols and climate dating back at least 12,000 years.

The ice core, collected from Mont Blanc’s Dôme du Goûter, provides a unique insight into Europe’s local climate during different time periods. By using radiocarbon dating techniques, the research team established that the glacier offers an accurate record of past atmospheric aerosols and climate transitions.

Aerosols play a significant role in regional climate through their interactions with clouds and solar radiation. The insights offered by this ice core record can help inform accurate climate modeling for both the past and future.

One of the most striking aspects of this study is that it reveals a temperature difference of about 3 degrees Celsius between the last Ice Age and the current Holocene Epoch. Using pollen records embedded in the ice, reconstructions of summer temperatures during the last Ice Age were about 2 degrees Celsius cooler throughout western Europe, and about 3.5 degrees Celsius cooler in the Alps.

The phosphorous record also tells researchers the story of vegetation changes in the region over the last 12,000 years. Phosphorous concentrations in the ice were low during the last Ice Age, increased dramatically during the early to mid-Holocene, and then decreased steadily into the late Holocene.

Records of sea salt also helped researchers examine changes in historical wind patterns. The ice core revealed higher rates of sea salt deposition during the last Ice Age that may have resulted from stronger westerly winds offshore of western Europe.

The most dramatic story told by this study is the change in dust aerosols during the climatic shift. Dust serves as an important driver of climate by both absorbing and scattering incoming solar radiation and outgoing planetary radiation, and impacts cloud formation and precipitation by acting as cloud condensation nuclei.

During the last Ice Age, dust was found to be about 8-fold higher compared to the Holocene. This contradicts the mere doubling of dust aerosols between warm and cold climate stages in Europe simulated by prior climate models.

This study is only the beginning of the Mont Blanc ice record’s story, as researchers plan to continue analyzing it for indicators of human history. The first step in uncovering every ice core’s record is to use isotopes and radiocarbon dating to establish how old each layer of ice is. Now, with that information, scientists can take an even deeper look at what it can tell us about past human civilizations and their impact on the environment.

The Mont Blanc ice record has the potential to reveal more stories entombed in its layers, and researchers are eager to continue exploring this ancient history for a better understanding of our planet’s climate variability and human history.

The United States is no stranger to bone-chilling winter cold, despite a warming climate. A recent study has shed light on why this phenomenon persists, pointing to two specific patterns in the polar vortex – a swirling mass of cold air high in the stratosphere. These variations can steer extreme cold to different regions of the country, often contradicting broader warming trends.

Researchers from an international team, including Prof. Chaim Garfinkel (Hebrew University), Dr. Laurie Agel and Prof. Mathew Barlow (University of Massachusetts), Prof. Judah Cohen (MIT and Atmospheric and Environmental Research AER), Karl Pfeiffer (Atmospheric and Environmental Research Hampton), and Prof. Jennifer Francis (Woodwell Climate Research Center), have published their findings in Science Advances.

The study reveals that since 2015, the Northwest US has experienced more of these cold outbreaks due to a shift in stratospheric behavior tied to broader climate cycles. In contrast, other regions may experience milder winters. Understanding this relationship can improve long-range forecasting, allowing cities, power grids, and agriculture to better prepare for winter extremes – even as the climate warms overall.

“It’s not just about warming everywhere all the time,” explained the researchers. “Climate change also means more complex and sometimes counterintuitive shifts in where extreme weather shows up.”

The work was funded by a US NSF-BSF grant by Chaim Garfinkel of HUJI and Judah Cohen of AER&MIT, highlighting the importance of international collaboration in addressing global climate challenges.