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Sylvia Dee

Sylvia Dee wins fellowship to launch Gulf of Mexico study

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MIKE WILLIAMS

– SEPTEMBER 28, 2021

National Academies back ‘bold’ research projects by early-career scientists

Sylvia Dee, an assistant professor of Earth, environmental and planetary sciences at Rice University, has won one of eight national early-career fellowships to pursue research that relates to the changing ecosystem of the Gulf of Mexico.

Sylvia Dee

Sylvia Dee

Dee was selected for the environmental protection and stewardship track of the 2021 Early-Career Research Fellowship (ECRF), announced by the Gulf Research Program (GRP) of the National Academies of Sciences, Engineering and Medicine. 

The Gulf is home to a wide variety of ecosystems including estuaries, oyster reefs, beaches and dunes, mangroves and offshore shoals and banks. Dee and her students focus their study on coral reefs, which are critically threatened in the Gulf. These fragile ecosystems continue to shift with climate change, urbanization and increased demand for food, water and energy. Predicting and anticipating these changes is essential to allocating natural resources in an equitable way while protecting the environment, according to the GHP.

The fellows will investigate specific issues related to Gulf ecosystems and produce research that helps enhance environmental protection and stewardship.

“This fellowship will be critical for supporting research in coral reef risk forecasting and mitigation,” Dee said. “Since moving to Texas, I’ve increasingly focused on local issues, and our coral reefs are critical to the ecosystem services we rely on in Houston. The grant will help us build capacity to predict, map and work with our collaborators at the Flower Garden Banks National Marine Sanctuary to protect the unique coral reefs in the Gulf of Mexico.”

The ECRF award is not attached to a specific project, which allows fellows to take on bold research they might not otherwise be able to pursue. All of the fellows are investigators, faculty members, clinician scientists or scientific team leads at colleges, universities and research institutions. Each of them will receive a $76,000 award, mentoring support and a built-in community of current and past cohorts.

“The opportunity to collaborate and interact with other early-career fellows is really exciting,” Dee said. “Our meetings provide us time to branch off into teams to identify research solutions by reaching across disciplines to work on a common problem. The mentoring component spans everything from work-life balance to networking. And in that way, the program really is designed to help us not only launch critical research, but also develop and grow as scientists and scholars.”

“Research that enhances environmental protection and stewardship requires both multidisciplinary thinking and the ability to build strong relationships with decision-makers,” said Karena Mary Mothershed, senior program manager for the GRP’s Board on Gulf Education and Engagement. “These exceptional fellows embody those qualities through their perseverance, creativity and inventiveness. One of the most unique aspects of the ECRF is that it supports people, not projects — and we’re excited to be a part of our fellows’ continued success and professional growth.”

The National Academies’ Gulf Research Program is an independent, science-based program founded in 2013 as part of legal settlements with the companies involved in the 2010 Deepwater Horizon disaster. Its goal is to enhance offshore energy system safety and protect human health and the environment by catalyzing advances in science, practice and capacity, generating long-term benefits for the Gulf of Mexico region and the nation.

PNAS: Climate models can correctly simulate the continuum of global-average temperature variability

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Feng Zhu, Julien Emile-Geay, Nicholas P. McKay, Gregory J. Hakim, Deborah Khider, Toby R. Ault, Eric J. Steig, Sylvia Dee, and James W. Kirchner
Proc. Natl. Acad. Sci. USA 116 (2019) 8728-8733.

DOI: 10.1073/pnas.1809959116

Significance

Climate models are foundational to formulations of climate policy and must successfully reproduce key features of the climate system. The temporal spectrum of observed global surface temperature is one such critical benchmark. This spectrum is known to obey scaling laws connecting astronomical forcings, from orbital to annual scales. We provide evidence that the current hierarchy of climate models is capable of reproducing the increase in variance in global-mean temperature at low frequencies. We suggest that successful climate predictions at decadal-to-centennial horizons hinge critically on the accuracy of initial and boundary conditions, particularly for the deep ocean state.

Abstract

Climate records exhibit scaling behavior with large exponents, resulting in larger fluctuations at longer timescales. It is unclear whether climate models are capable of simulating these fluctuations, which draws into question their ability to simulate such variability in the coming decades and centuries. Using the latest simulations and data syntheses, we find agreement for spectra derived from observations and models on timescales ranging from interannual to multimillennial. Our results confirm the existence of a scaling break between orbital and annual peaks, occurring around millennial periodicities. That both simple and comprehensive ocean–atmosphere models can reproduce these features suggests that long-range persistence is a consequence of the oceanic integration of both gradual and abrupt climate forcings. This result implies that Holocene low-frequency variability is partly a consequence of the climate system’s integrated memory of orbital forcing. We conclude that climate models appear to contain the essential physics to correctly simulate the spectral continuum of global-mean temperature; however, regional discrepancies remain unresolved. A critical element of successfully simulating suborbital climate variability involves, we hypothesize, initial conditions of the deep ocean state that are consistent with observations of the recent past.

QSR: Evidence of Ice Age humans in eastern Beringia suggests early migration to North America

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Richard S. Vachula, Yongsong Huang, William M. Longo, Sylvia G. Dee, William C. Daniels, and James M. Russell

Quant. Sci. Rev. 205 (2019) 35-44.

DOI: 10.1016/j.quascirev.2018.12.003

 

Abstract

Our understanding of the timing and pathway of human arrival to the Americas remains an important and polarizing topic of debate in archaeology and anthropology. Traditional consensus, supported by archaeological and paleoenvironmental data, favors a ‘swift peopling’ of the Americas from Asia via the Bering Land Bridge during the last Glacial termination. More recent genetic data and archaeological finds have challenged this view, proposing the ‘Beringian standstill hypothesis’ (BSH), wherein a population of proto-Americans migrated from Asia during, or even prior to the Last Glacial Maximum (LGM) and lived in Beringia for thousands of years before their eventual spread across the American continents. Using a sediment archive from Lake E5 (68.641667° N, 149.457706° W), located on Alaska’s North Slope, we present new data supporting the BSH and shedding new light on the environmental impact of these early American populations. Fecal biomarkers support human presence in the environs of the lake, and our data demonstrate elevated biomass burning in this region during the last Glacial. Elevated burning defies the expectation that natural fires would be less frequent in the Arctic during the last Glacial, thereby suggesting human ignition as the likely culprit. Our data shed new light on the pathway and timing of human migration to the Americas and demonstrate the possibility of the sustainable coexistence of humans and the Ice Age megafauna in Beringia prior to their extinction.