geoscience | University of 贬补飞补颈驶颈 System News /news News from the 东精影业 Thu, 13 Feb 2025 01:49:14 +0000 en-US hourly 1 /news/wp-content/uploads/2019/04/cropped-UHNews512-1-32x32.jpg geoscience | University of 贬补飞补颈驶颈 System News /news 32 32 28449828 Alumna spreads inclusivity in science through NSF /news/2023/04/11/morris-spreads-inclusivity-in-science/ Tue, 11 Apr 2023 22:54:43 +0000 /news/?p=175598 Aisha Morris is one of NSF鈥檚 program directors for geosciences, overseeing opportunities and resources for researchers and educators nationwide.

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aisha morris
Aisha Morris

While the University of Hawaiʻi at M膩noa (SOEST) is typically credited with significant discovery and research, it is also recognized for helping students, faculty and staff discover and pursue their lifelong goals.

东精影业 M膩noa alumna Aisha Morris is one of them. She found her calling of advancing inclusivity in science during her time as a graduate student at SOEST, which ultimately led her to become a program director for the National Science Foundation鈥檚 (NSF) Directorate for Geosciences (GEO).

Morris has been an NSF GEO program director since October 2018. In her role, she helps facilitate the funding for research, manages proposal reviews and makes compelling arguments to division directors on why a proposal should receive financial support.

Additionally, Morris works with a team to develop funding opportunities for people nationwide. When recommending projects to be funded, she works to ensure that taxpayer dollars are being responsibly stewarded and that local communities are not harmed from the research being conducted.

“I work with this great core team, and we develop things that can benefit the community when it seems like something they really need, or something that really needs funding to be accomplished,” said Morris. “A lot of the questions that we鈥檙e asking [in science] have real life impacts on people鈥檚 lives. I really want to ensure that the people that are being impacted, even if they鈥檙e not necessarily doing the research, are still being involved in the decision making.”

SOEST catalyst

woman in inactive volcanic area
Morris during a 东精影业 volcanology field trip to New Zealand in March 2004.

Morris earned her master鈥檚 in marine geoscience (鈥03) and her PhD in planetary geoscience (驶08) from 东精影业 M膩noa. While at SOEST, she developed a project to examine the different surface roughness of pah艒膿h艒膿 (smooth) lava flows on K墨lauea and took numerical measurements that could potentially be used to determine different lava flows on other planets.

“It was huge to be able to come to SOEST which had super strong programs and gave me the ability to get both my master鈥檚 and PhD, and K墨lauea was just a 45-minute plane ride away to do some field work on the volcano,” said Morris. “It was just a great opportunity to study the things that I thought were going to be really cool.”

Morris also took part in SOEST open houses where Oʻahu schools and families could tour the facilities and perform experiments with the SOEST students, faculty and staff.

“This was one of the things that helped catalyze my interest in doing those kinds of activities that allowed me to engage, to connect with the community, to connect with students who maybe never thought about geoscience as something they could pursue,” said Morris. “It was one of the great experiences I had when I was at SOEST.”

In addition to her desire to do outreach, Morris also found motivation to make the geoscience community more inclusive.

Morris shared, “While I was there, I started to notice that there weren鈥檛 a lot of people of color who do geoscience, which was really odd, even in the department. At the time that I was there, the department wasn鈥檛 representative of Hawaiʻi. I liked the research, but the thing that was really driving me more was trying to address these disparities that we鈥檙e seeing here.”

Morris has experienced different work environments, from doing science policy work with the U.S. House of Representatives to creating internship programs for students at UNAVCO in Boulder, Colorado. She credits her geoscience training from SOEST with informing her on how to interact with students, communities and research projects.

Puwalu Forum

东精影业 M膩noa faculty, staff and students will have the opportunity to hear sage advice from Morris and other NSF representatives during a Faculty Puwalu Research Forum hosted by the Office of the Vice Provost for Research and Scholarship. NSF will be presenting May 2–4, 2023 to discuss broadening participation in STEM, NSF funding opportunities and proposal tips and more.

woman in front of inactive volcano
Morris researched volcanic areas in New Zealand through 东精影业.
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Love of 驶膩ina, community motivated grad student through doctoral degree /news/2022/05/17/doctoral-degree-diamond-tachera/ Wed, 18 May 2022 00:59:05 +0000 /news/?p=159324 Diamond Tachera, a life-long student in Mānoa Valley, joined the spring 2022 commencement celebration after completing a doctoral degree in Earth sciences.

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woman water sampling
Tachera sampling a rain collector on Hawaiʻi Island. (Photo credit: Kiana Frank)

Diamond Tachera, a life-long student in Mānoa Valley, joined the spring 2022 commencement celebration after completing a doctoral degree in at the University of Hawaiʻi at Mānoa (SOEST).

Though she grew up in Kalama Valley, Oʻahu, Tachera considers Mānoa as part of her home—having attended University Laboratory School from kindergarten through high school. In her senior year, Tachera鈥檚 science teacher Lauren Kaupp, who received her master鈥檚 degree in oceanography from SOEST and a doctoral degree in education at 东精影业 Mānoa, invited Tachera to walk around campus during the 2009 biennial SOEST open house event.

woman wearing leis
Tachera after her dissertation defense.

“We accidentally opened the door on Gerard Fryer, who was practicing his presentation for later that day,” said Tachera. “He invited us in for a private lecture on tsunamis and earthquakes in Hawaiʻi. At that time, I wanted to be a geophysicist and study earthquakes, so it was a truly magical experience! I will never forget the kindness that Gerard shared in that moment, and how warm and comforting it felt to be in that space.”

Tachera attended for two years, worked in the Kapiʻolani CC STEM Center with Keolani Noa, and was recruited into the first cohort of the SOEST Maile Mentoring Bridge Program. Once she transferred to 东精影业 Mānoa, Tachera pursued an undergraduate degree in the Department of Earth Sciences (formerly Geology and Geophysics), where she immersed herself in learning about Earth system processes, engaged with mentors and found additional inspiration for her pursuits.

Mentors encourage graduate school

More highlights from the commencement ceremonies and our amazing graduates

Through the internships and research experience, her passion for Earth science continued to grow and she completed her bachelor鈥檚 degree in geology and geophysics in 2016. But she was unsure about enrolling in the graduate program.

“I doubted myself but with encouragement from some of my mentors, such as Barb Bruno and Tiffany Anderson, I applied to graduate school,” she said.

For her doctoral research, Tachera focused on understanding the geochemical changes of water as it moves through the water cycle of West Hawaiʻi Island with SOEST researcher Nicole Lautze as her advisor. She collected more than two years of data on rainfall and groundwater to better understand vital freshwater resources in the area.

“I really wanted to do research that was focused in Hawaiʻi. I am truly grateful for this opportunity, because the research was more than a job to me,” said Tachera. “It was a powerful experience to work on a project that would hopefully benefit the Native Hawaiian community especially as we continue to face climate change impacts more and more each year.”

Representation and Indigenous knowledge in science

woman with bucket
Tachera collecting rain samples on Mauna Kea. (Photo credit: Kiana Frank)

“Growing up, being Hawaiian was just a part of everyday life,” said Tachera. “When I became a student at 东精影业, I really felt a sense of Hawaiian pride. My academic and personal journey over the past 12 years has led me to focus my energy and research on issues that are important to our local community and also motivated me to work toward making geoscience more inclusive and equitable.”

Tachera published an article in outlining a powerful approach to increase equity and inclusion of Indigenous knowledge and communities in science—reframing funding strategies.

“The geosciences are historically exclusive,” said Tachera. “Updating funding systems is just one step toward greater inclusion and accountability across all levels of academia and will result in science that is mutually beneficial to, and respectful of, everyone involved.”

Turning to the past for future sustainability

For her next endeavor, Tachera was selected as a postdoctoral fellow for the Advanced Studies Program at the National Corporation for Atmospheric Research (NCAR). The focus of her research will be on combining various data sets, such as historical Hawaiian language nūpepa (newspapers), traditional moʻolelo (stories) and western scientific reports to provide new insights that support sustainable water resources and address potential changes in climate patterns over the last few centuries.

“This support from NCAR to integrate science and culture is really exciting,” said Tachera. “It鈥檚 so meaningful to me to have opportunities that elevate Hawaiian history, culture and people, and that really focus on outputs that benefit my community.”

This effort is an example of 东精影业 Mānoa鈥檚 goal of (PDF), (PDF), (PDF) and (PDF), four of four goals identified in the (PDF), updated in December 2020.

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New program supports Asian American, Pacific Islander students in geoscience /news/2021/12/14/program-supports-aapi-geoscience/ Wed, 15 Dec 2021 01:42:32 +0000 /news/?p=153218 The $209,243 grant project aims to improve the awareness of geosciences among AAPI undergraduates.

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students working outside

The is partnering with seven other institutions on a new initiative that fosters belonging and participation among Asian Americans and Pacific Islander (AAPI) students in the geosciences. The National Science Foundation-funded project, titled AGILE (AAPI in Geoscience: Inclusivity, Leadership, and Experience), is led by Daniel Ibarra, at Brown University and Kimberly Lau at Penn State.

With the support of a $209,243 grant, the project aims to improve the awareness of geosciences among AAPI undergraduates and cultivate a national network of mentors that will boost AAPI participation in geoscience graduate programs and careers.

With 东精影业 Mānoa being an Asian American and Native American Pacific Islander-serving institution, and the 东精影业 Mānoa (SOEST) being one of the premier geoscience schools in the world, SOEST is well-positioned to play a role in helping increase participation of AAPI in the geosciences.

aapi in geoscience

David Ho, from SOEST鈥檚 and co-investigator on the new project, will work with the other partners on establishing the research visit program and the research internship program, as well as participate in career development events and workshops. These efforts connect students with invaluable research experiences and enhance professional skills needed to succeed in the field of geosciences.

“The Earth and environmental sciences impact every person on our planet in some way, and so it鈥檚 a priority that our field is as inclusive as possible,” said Lau. “Who gets to become a geoscientist is a topic that the community has been focusing on. Through this project, we aim to provide more exposure to the Earth and environmental sciences, as well as create new opportunities for AAPI undergraduates to learn about how they can make an impact.”

The grant funds exciting new initiatives, including a pilot research visit program that will support short visits by faculty, graduate students and other scientists to AAPI-serving institutions to bring awareness of geoscience careers and graduate school to AAPI students. The project also includes career-development events and workshops, and an undergraduate research internship that will connect students with meaningful geoscience research and learning opportunities.

Through all of this, the project plans to expose as many as a thousand undergraduates across the country to geoscience research and careers, establish a new research internship opportunity, and create national cross-career connections between AAPI geoscientists in diversity and inclusion discussions.

This program is an example of 东精影业 Mānoa鈥檚 goal of (PDF), (PDF) and (PDF), three of four goals identified in the (PDF), updated in December 2020.

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东精影业 professor honored for cooperation, leadership in geoscience /news/2021/08/24/gregory-moore-honored-geoscience/ Tue, 24 Aug 2021 20:28:40 +0000 /news/?p=146883 Gregory Moore has been studying Asian geology—mapping the structure and stratigraphy of deep sea trenches, subduction zones, mud volcanoes and more.

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man smiling
Gregory Moore

An emeritus professor in the at the University of Hawaiʻi at Mānoa, was honored by the with the “for his unselfish cooperation and leadership in geoscience in the Asia Oceania region.”

For more than 45 years, Gregory Moore has been studying Asian geology—mapping the structure and stratigraphy of deep sea trenches, subduction zones, mud volcanoes and more. He was a 东精影业 Mānoa professor in the from 1989 to 2020. Previously, he was an associate professor at the University of Tulsa and an assistant research geologist at Scripps Institution of Oceanography.

Throughout his research, Moore has worked with organizations such as the Indonesian Institute of Sciences, Geological Survey of Indonesia, Philippine Bureau of Mines and Geology, Japan Agency for Marine-Earth Science and Technology, University of Tokyo, National Taiwan University, Myanmar Geoscience Society and the Earth Observatory of Singapore and their staff, who assisted with logistics and accompanied Moore in the field and on research cruises.

“The continued success of my field-based studies has only been possible with the assistance, participation and local knowledge of numerous colleagues from Indonesia, the Philippines, Taiwan, Japan, Myanmar and New Zealand, all of whom I thank profusely,” said Moore.

Mapping Asia Oceania region

During graduate school at Cornell University, Moore spent three field seasons mapping the structure and stratigraphy of Nias Island, Indonesia. During his time at Scripps, he jointly led a marine geophysical cruise to the Sunda Trench offshore Java and Sumatra and conducted land field work in Indonesia and Philippines; and jointly led a seismic cruise to the Taiwan collision zone.

Moore began a decades-long investigation of the Nankai Trough subduction zone in 1987 on a joint cruise with colleagues from Tokyo University and the University of Texas and collaborative analyses of seismic data collected by Japanese colleagues. While continuing with Nankai studies, he also investigated mud volcanoes in the Rakhine State of Myanmar, joined an expedition to the Hikurangi margin of New Zealand and is now analyzing a 3D seismic data set from Hikurangi.

“It is very nice to have the recognition of a regional Geoscience Society for my continued work in South East Asia and its relevance, not only to subduction zone science, but also to ‘capacity building’ in the region,” said Moore. “By working with young scientists and passing on our experience, we increase their ability to conduct their own research to better understand their countries鈥 natural hazards and natural resources.”

This work is an example of 东精影业 Mānoa鈥檚 goal of (PDF), one of four goals identified in the (PDF), updated in December 2020.

–By Marcie Grabowski

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New hands-on course guides UH community college students to M膩noa /news/2018/08/07/new-hands-on-course-guides-uh-community-college-students-to-manoa/ Tue, 07 Aug 2018 17:27:42 +0000 /news/?p=82897 Mauka to Makai is a six-week bridge program that goes beyond the usual lectures and laboratory activities.

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students on pier with water testing equipment
Students at Makai Pier testing collecting water samples. (Credit: Mauka to Makai students)

A new oceanography course is being offered this summer in the at the (SOEST). SOEST Mauka to Makai is a six-week bridge program that goes beyond the usual lectures and laboratory activities to include tutorials, coastal cruises and service-learning activities.

Funded as part of an award from the National Science Foundation Tribal Colleges and Universities Program to students at , , and 东精影业 M膩noa, this fresh approach aims to provide hands-on learning in the natural environment. A unique aspect of the course is its connection with community groups involved in the preservation and restoration of traditional Hawaiian resource management practices in watersheds and coastal waters of Oʻahu.

students working in a taro patch
Students in Ka Papa Loʻi ʻo K膩newai at 东精影业 M膩noa. (Credit: Mauka to Makai students)

Students from 东精影业 community colleges with an interest in science and solid academic records, who are interested in coming to 东精影业 M膩noa for a four-year degree in the geosciences, were encouraged to apply for the course. This summer, 11 students representing Honolulu, Kauaʻi, and Windward CCs are enrolled.

“This course is different from the typical introductory oceanography class in that it has been restructured to be place-based, exposing the students to specific challenges being faced by communities across Oʻahu and the local organizations that are tackling them,” said , co-principal investigator and oceanography professor.

The course involves faculty from across SOEST, enabling students to interact with researchers in a broad array of geoscience-related disciplines and allowing students to see first-hand the real-life application of the research being carried out at this institution.

Tapping into Hawaiʻi‘s local talent pool

“This course is part of an overall effort to create more pathways between the 东精影业 community colleges and 东精影业 M膩noa in the geosciences (atmospheric science, environmental science, geology, oceanography), with the end goal of having more underrepresented minorities in the geosciences graduate with geoscience-related degrees,” said , co-principal investigator for the course and chair of the SOEST .

“Native Hawaiians and other ethnic minority groups, including Pacific Islanders, Filipinos, Hispanics, African Americans and Native Americans, are underrepresented at both the undergraduate and graduate levels in SOEST,” said , co-principal investigator and assistant professor in SOEST oceanography and University of Hawaiʻi . “In an effort to tap into Hawaiʻi‘s local talent pool, SOEST is actively partnering with community colleges to recruit 办补尘补ʻ腻颈苍补 students into our degree programs.”

The overarching goal of these partnerships is to foster a transfer pathway from the community colleges to geoscience degree programs at 东精影业 M膩noa, with a focus on Native Hawaiian and other underrepresented students. The natural pathway from the community colleges in the 东精影业 system to 东精影业 M膩noa facilitates administrative collaboration and student transfer.

The National Science Foundation Tribal Colleges and Universities Program grant covers summer tuition and associated fees, six weeks of room and board on the M膩noa campus and a stipend for the participating students. The SOEST Mauka to Makai course will be offered each summer for the next three years as a pilot program.

—By Marcie Grabowski

students and teacher near ocean
Students with SOEST geologist Scott Rowland on southeast Oʻahu. (Credit: Mauka to Makai students)
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Summer Bridge program diversifies undergraduate enrollment /news/2016/08/03/summer-bridge-program-diversifies-undergraduate-enrollment/ Wed, 03 Aug 2016 23:03:47 +0000 http://www.hawaii.edu/news/?p=48378 A study by 东精影业 Mānoa and Kapiʻolani CC shows Summer Bridge program effective in encouraging students toward geosciences.

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Students on a geology field trip

Researchers from the and investigated the effectiveness of Kapiʻolani CC’s Summer Bridge program in diversifying undergraduate enrollment by encouraging STEM students to pursue further education in geosciences.

东精影业 Mānoa’s Barbara Bruno, Johanna Wren, Jessica Ayau, Sherril Leon Soon, Heidi Needham, Elisha Wood-Charlson, Anela Choy and Kapiʻolani CC’s Keolani Noa published “” in the magazine.

The Kapiʻolani CC brings together high school students, college student peer mentors and college faculty to help students prepare for the rigors of college math and science. There are two tracks—HāKilo (ecology) or ʻIKE (engineering) that feature learning and work opportunities in these fields each afternoon. Over the summer, students not only learn about college, they also explore the relevance of modern science and engineering to sustainability and Hawaiʻi’s past, present and future.

Students investigating a tree
Students on a field trip

Evaluating the program

To evaluate program efficacy, the researchers developed a nine-question survey to measure familiarity with geoscience majors, perceptions about geoscience, self-efficacy and desire to pursue geoscience majors and careers. Sixty-four students participated in the program over a three-year period. Approximately two-thirds of students are from groups that are underrepresented in STEM and approximately one-third are Native Hawaiian. Only a small number of these students expressed interest in geoscience majors prior to program participation, and many were not even aware that geoscience majors existed.

By the end of the weeklong program, the students showed learning gains on all nine questions, and eight of these gains were statistically significant. To date, five summer bridge alumni (four Native Hawaiian) have declared geoscience majors, representing 31 percent of 东精影业 Mānoa’s Native Hawaiian geoscience enrollment. This suggests that partnering with a minority-serving community college may be an effective, time-efficient way of increasing minority enrollment in geoscience majors.

Read the (PDF) at the Oceanography website.

东精影业 News video on the Summer Bridge Program

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Ancient trail at Hawaiʻi Community College鈥揚膩lamanui mapped /news/2015/12/15/ancient-trail-at-hawaii-community-college-palamanui-mapped/ Tue, 15 Dec 2015 23:13:33 +0000 http://www.hawaii.edu/news/?p=41284 Hawaiʻi CC students use their technology skills to help preserve part of an ancient Native Hawaiian trail.

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hawaii G I S students

students who are studying global positioning systems (GPS) and geographic information systems (GIS) recently used their technology skills to help preserve part of an ancient Native Hawaiian trail.

The trail—which features petroglyphs, caves, and ancient lama trees—is next to the new Hawaiʻi Community College–Pālamanui campus in Kona. Until recently the trail was overgrown with invasive fountain grass and forgotten.

students hiking

Since June 2014, trail expert and Hawaiʻi CC–Pālamanui humanities lecturer Richard Stevens has been leading an effort to restore the mauka-to-makai pathway. Many students and community volunteers have ripped out fountain grass and moved rocks to help reclaim the trail from nature.

Mapping the trail

Now the goal is to keep track of the trail, and that’s where the students enrolled in Introduction to GIS and GPS come in.

“The class’ work is hugely important,” said Stevens. “The trail won’t be lost again: It’s carved into cyberspace.”

On a hot Saturday morning on November 14, 2015, the Hawaiʻi CC students used their handheld GPS devices to mark significant locations along the trail, including the petroglyphs and caves.

“Now we’re going to take that data and put it into a GIS map and basically create a base map of the trail and all the significant locations,” said Victor Rasgado, a geomatics lecturer at Hawaiʻi CC. “So we’re preserving that trail, and we’re doing it with new technologies.”

Sterling Chow, one of the students in the class, said he and his classmates gathered GPS data, took detailed notes, and snapped pictures in order to compile enough information to create a map.

“It’s a great learning tool, being out there, tying the information together, and accurately describing what you saw,” said Chow.

The trail is on land owned by Pālamanui, LLC, which is the private development company planning a mixed-use community next to the campus. Preservation of the trail is part of the company’s cultural resource management plan.

Learning from this cultural treasure

The GIS and GPS class’ excursion is just the latest example of college faculty using the trail as a classroom. Stevens has taken his writing and history students there, and the Hawaiʻi CC–Pālamanui campus has plans to continue using it as an educational resource.

“Trails are cultural treasures, living artifacts showing the ingenuity and survivability of the ancient Hawaiians in nature,” said Stevens. “Recording those treasures on maps helps us not lose the lessons they have to teach us.”

More about Hawaiʻi CC’s geospatial technology courses

The Introduction to GIS and GPS course is one of four classes Hawaiʻi CC students take in order to earn a certificate in geospatial technology. The courses and the certificate are part of the Architectural, Engineering and CAD Technologies program at Hawaiʻi CC, which offers three certificates and an Associate in Applied Science degree.

—By Thatcher Moats

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Evidence for both mixing and layering of Earth鈥檚 interior clarifies long-standing debate /news/2015/12/10/evidence-for-both-mixing-and-layering-of-earths-interior-clarifies-long-standing-debate/ Thu, 10 Dec 2015 23:15:26 +0000 http://www.hawaii.edu/news/?p=41156 A new study suggests that mixing due to mantle flow occurs on a global scale, but discrete layers where material with similar composition has aggregated are maintained.

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Earth's upper mantle
Some slabs sink deep into the mantle, others stall at approximately 1,000 km depth. This behavior can be explained by moderate mantle layering with an accumulation of basalt (blue squiggles) in the lower mantle. Basalt was originally been subducted into the mantle as oceanic crust, and is recycled by plumes that feed volcanoes beneath a hotspot. (credit: M. Ballmer)

Earth’s mantle, the large zone of slow-flowing rock that lies between the crust and the planet’s core, powers every earthquake and volcanic eruption on the planet’s surface. There has been a long-standing debate in the geosciences on whether the lower and upper mantles are different in composition or well mixed. by lead author Maxim Ballmer, senior scientist at ETH Zurich and former postdoctoral fellow at the University of Hawaiʻi at Mānoa’s , suggests that mixing due to mantle flow indeed occurs on a global scale, but discrete layers where material with similar composition has aggregated are nevertheless maintained.

Whereas the composition of Earth’s upper mantle can be estimated from lava outpourings on the ocean floor at mid-ocean ridges, the lower mantle remains poorly understood. Chemical observations indicate that the composition of the lower mantle may be different from the composition of the upper mantle. On the contrary, seismic tomography—creating images of Earth’s interior using earthquake-generated waves—provides evidence that the whole mantle is stirred, and presumably well-mixed.

Into the depths unknown

Many huge slabs of ocean crust that have been dragged down, or subducted, into the mantle can still be detected in the deep Earth. These slabs slowly sink downward toward the bottom of the mantle. Some slabs sink all the way down, providing evidence for global stirring of the mantle by a process called “whole-mantle convection.” However, a large number of these slabs have stalled out and appear to float 1,000 kilometers deep, indicating a notable change in physical properties with depth. Ballmer and colleagues exploited this natural phenomenon to gain insight into a region no human or machine can reach.

Ballmer and researchers from the , and used a computer model of a simplified Earth. Each run of the model began with a slightly different chemical composition鈥攁nd thus a different range of densities鈥攊n the mantle at various depths. The researchers then used the model to investigate how slabs of ocean crust would behave as they travel down toward the lower mantle.

Answers and more questions

They discovered that the layering—with slightly denser material in the lower mantle than in the upper mantle—can explain the “floating” of some slabs at approximately 1,000 km depth. The authors suggest the lower mantle may be a mix of rock types, but enriched in some intrinsically denser rock type. The most likely candidate, they say, is subducted mid-ocean ridge basalt that has accumulated in the lower mantle over hundreds of million years. Basalt is ultimately picked up by mantle plumes, hot rising columns of mantle rock that sustain surface hotspots of volcanism such as on the Big Island of Hawaiʻi—exemplifying the mantle’s true nature as the ultimate recycler.

The finding that the mantle may be layered led to another conundrum: how can the layering survive for geologic timescales of billions of years, as slabs continuously sink through the mantle and cause global-scale mixing? To answer this question, Ballmer and co-authors set up another model of global convection, which simulates the evolution of the Earth over 4陆 billion years.

Surprises in Earth’s interior

“Surprisingly, the models showed that moderate mantle layering can be sustained, even in the presence of whole-mantle convection,” said Ballmer. “Layering can be sustained by “unmixing” of rocks with different density—similar to an oil and water mixture separating over time. This unmixing competes with mixing during mantle convection.” Thus, whole-mantle convection and moderate layering of rock types are not mutually exclusive, contrary to previous thinking.

In the future, Ballmer and colleagues will assess the combined effects viscosity and density. If the rock types in the mantle not only differ in density, but also in viscosity (like water and honey), this should have strong effects on mixing as well as “unmixing” processes.

“If the lower mantle has a different viscosity than the upper mantle, the related feedback on mantle convection and mixing may affect our understanding of Earth evolution,” Ballmer said.

Researchers are indeed just beginning to decipher the messages from the deep mantle, and its role in global recycling, which may have been key to maintain stable and life-friendly conditions on the Earth’s surface over the past billions of years.

—By Marcie Grabowski

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Lake Tahoe research provides new insights on global change /news/2015/03/12/lake-tahoe-research-provides-new-insights-on-global-change/ Thu, 12 Mar 2015 23:41:14 +0000 http://www.hawaii.edu/news/?p=32646 A study on how natural and man-made sources of nitrogen are recycled through the Lake Tahoe ecosystem provides new information on how global change may affect the iconic blue lake.

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Lake Tahoe, Emerald Bay (photo credit: Brant Allen, UC Davis Tahoe Environmental Research Center)

A team of researchers, including Stuart Goldberg, published a study on how natural and man-made sources of nitrogen are recycled through the Lake Tahoe ecosystem provides new information on how global change may affect the iconic blue lake.

“The things we do, as humans, affect change in nature. We know the Lake’s foodweb is changing due to warming and nitrogen inputs. Our marine and aquatic ecosystems across the globe face many of the same environmental stressors,” said Goldberg, lead author of the study and post-doctoral researcher at the (He was a post-doctoral researcher at Scripps Oceanography during this research).

What we’ve learned about how aquatic foodwebs recycle nitrogen in Lake Tahoe may be applicable to the clear waters near Hawaiʻi,” said Goldberg.

Lake Tahoe is a sentinel of climate change

, tracked nitrogen, including that produced from the burning of fossil fuels, in the Lake Tahoe ecosystem. Nitrogen can affect both the productivity of lake foodwebs and the composition of the microbes that support nutrition for those food webs.

Lake Tahoe’s nitrogen concentration is one of several factors that helps maintain its crystal clear waters. To keep Tahoe blue in the future, the researchers say it’s important to keep a close eye on the nitrogen balance in the ecosystem over time.

“High-elevation lakes, such as Lake Tahoe, are sentinels of climate change,” said Lihini Aluwihare, associate professor of geosciences at at and co-author of the study. “Small changes in the lake’s chemistry can have big impacts on the entire ecosystem.”

The many forms of nitrogen

A main goal of the study was to understand how the nutrient is being cycled through the microbial food web. Goldberg compares the foodweb to a cafeteria that sends out a variety of different dining options that support the community as a whole. Nutrients like nitrogen, phosphorus and carbon come in, and the foodweb changes them into different types of nitrogen, phosphorus and carbon—proteins, sugars and fats, for example. Some types are easier to eat than others and are reused or eaten almost instantly. Other types, like the proteins isolated for this study, aren’t easily consumed and accumulate in the Lake.

Using radiocarbon isotope techniques, the researchers dated the molecular components of these proteins and discovered that some nitrogen was preserved in proteins and unavailable for biological consumption for 100 to 200 years.

“It is unusual for organic nitrogen to be sitting around for long periods of time in an ecosystem,” said Aluwihare. “This changes our view of how quickly nutrients are recycled in high-elevation lake ecosystems.”

The findings of this study suggest that something is preventing the efficient recycling of nitrogen in these ecosystems, and one possibility may be phosphorus limitation of the recycling bacteria (bacteria need both nitrogen and phosphorus to live).

The Lake Tahoe ecosystem is experiencing rapid change due to regional warming and shifts in precipitation patterns, as well as increased atmospheric nitrogen deposition, which has begun to alter the nutrient balance in the lake.

“This investigation has found that dissolved organic matter can store nitrogen in lake systems,” said Lina Patino, program director for the Earth Sciences Postdoctoral Fellowship Program at the , which funded the research. “This result is important because to understand the environmental health of lakes, we need to know the sources of the nutrients and where they are stored.”

Additional co-authors include Ian Ball at Scripps Oceanography; Brant Allen and Geoffrey Schladow at UC Davis; Andre Simpson, Hussain Masoom and Ronald Soong of the University of Toronto and Heather Graven of Imperial College in London.

—By Marcie Grabowski

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