Until now, computer models have been the primary tool for estimating photosynthetic productivity on a global scale. They are based on estimating a measure for plant energy called gross primary production (GPP), which is the rate at which plants capture and store a unit of chemical energy as biomass over a specific time. Joe Berry was part of a team that took an entirely new approach by using satellite technology to measure light that is emitted by plant leaves as a byproduct of photosynthesis as shown by the artwork.

The plant produces fluorescent light when sunlight excites the photosynthetic pigment chlorophyll. Satellite instruments sense this fluorescence yielding a direct observation of photosynthesis on a large scale for the first time. The team measured the fluorescence from large areas of crops in the Midwestern Corn Belt and the Indo-Gangetic Plain. The new data produced values that are 50% to 75% higher than state-of-the-art carbon cycle models, indicating that the models are severely underestimating. Image courtesy Pat Rawlings, Keck Institute for Space Studies

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Artist's concept of hydrogen fuel production. Purchased from Shutterstock.
July 20, 2021

Washington, DC—Designing future low-carbon energy systems to use power generated in excess of the grid’s demands to produce hydrogen fuel could substantially lower electricity costs, according to new work published by Advances in Applied Energy by Carnegie’s Tyler Ruggles and Ken Caldeira.

Renewable energy sources like the Sun and wind have natural variation due to weather patterns—some days are bright and clear, others are overcast; some days are blustery, others are still. This means that renewable power-generating infrastructure needs to be designed with this variability in mind.

To ensure that there is enough power available to meet society

Photograph of an offshore wind farm purchased from Shutterstock.
June 28, 2021

Washington, DC—Location, location, location—when it comes to the placement of wind turbines, the old real estate adage applies, according to new research published in Proceedings of the National Academy of Sciences by Carnegie’s Enrico Antonini and Ken Caldeira.

Turbines convert the wind’s kinetic energy into electrical energy as they turn. However, the very act of installing turbines affects our ability to harness the wind’s power. As a turbine engages with the wind, it affects it. One turbine’s extraction of energy from the wind influences the ability of its neighbors to do the same.

“Wind is never going to ‘run dry’

Close up of a leaf, courtesy of Pixabay
June 9, 2021

Washington, DC—The fact that photosynthesis uses sunlight and atmospheric carbon dioxide to produce sugars has been known for more than a century. But how photosynthesis manages to maintain sugar production through variations in the availability of sunlight and carbon dioxide has remained a mystery until now.

New work published in Photosynthesis Research from Carnegie’s Jennifer Johnson and Joseph Berry reveals that an enigmatic enzyme called the cytochrome b6f complex coordinates the process of capturing sunlight and carbon dioxide.

Through photosynthesis, plants provide the foundation for life on Earth by capturing the Sun’s energy and converting it into

Midwestern farm purchased from Shutterstock
May 20, 2021

Washington, DC—Models of the carbon cycle that are used to understand the effects of climate change in North America need to do a better job of accounting for the carbon dioxide removed from the atmosphere by Midwestern agricultural crops during the growing season, according to new work led by Carnegie’s Wu Sun and Department of Global Ecology Director Anna Michalak.  Their work, published in AGU Advances, has implications for scientists as well as policymakers. 

Plants are capable of turning the Sun’s energy into food using a physiological process called photosynthesis. They take up carbon dioxide from the atmosphere through pores in their leaves and,

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Anna Michalak’s team combined sampling and satellite-based observations of Lake Erie with computer simulations and determined that the 2011 record-breaking algal bloom in the lake was triggered by long-term agricultural practices coupled with extreme precipitation, followed by weak lake circulation and warm temperatures. The bloom began in the western region in mid-July and covered an area of 230 square miles (600 km2). At its peak in October, the bloom had expanded to over 1930 square miles (5000 km2). Its peak intensity was over 3 times greater than any other bloom on record. The scientists predicted that, unless agricultural policies change, the lake will continue to experience

Coral reefs are havens for marine biodiversity and underpin the economies of many coastal communities. But they are very sensitive to changes in ocean chemistry resulting from greenhouse gas emissions, as well as to pollution, warming waters, overdevelopment, and overfishing. Reefs use a mineral called aragonite, a naturally occurring form of calcium carbonate, CaCO3, to make their skeletons.  When carbon dioxide, CO2, from the atmosphere is absorbed by the ocean, it forms carbonic acid—the same stuff that makes soda fizz--making the ocean more acidic and thus more difficult for many marine organisms to grow their shells and skeletons and threatening coral reefs globally.

Johanna Teske became the first new staff member to join Carnegie’s newly named Earth and Planets Laboratory (EPL) in Washington, D.C., on September 1, 2020. She has been a NASA Hubble Fellow at the Carnegie Observatories in Pasadena, CA, since 2018. From 2014 to 2017 she was the Carnegie Origins Postdoctoral Fellow—a joint position between Carnegie’s Department of Terrestrial Magnetism (now part of EPL) and the Carnegie Observatories.

Teske is interested in the diversity in exoplanet compositions and the origins of that diversity. She uses observations to estimate exoplanet interior and atmospheric compositions, and the chemical environments of their formation

Phillip Cleves’ Ph.D. research was on determining the genetic changes that drive morphological evolution. He used the emerging model organism, the stickleback fish, to map genetic changes that control skeletal evolution. Using new genetic mapping and reverse genetic tools developed during his Ph.D., Cleves identified regulatory changes in a protein called bone morphogenetic protein 6 that were responsible for an evolved increase in tooth number in stickleback. This work illustrated how molecular changes can generate morphological novelty in vertebrates.

Cleves returned to his passion for coral research in his postdoctoral work in John Pringles’ lab at Stanford

Brittany Belin joined the Department of Embryology staff in August 2020. Her Ph.D. research involved developing new tools for in vivo imaging of actin in cell nuclei. Actin is a major structural element in eukaryotic cells—cells with a nucleus and organelles —forming contractile polymers that drive muscle contraction, the migration of immune cells to  infection sites, and the movement of signals from one part of a cell to another. Using the tools developed in her Ph.D., Belin discovered a new role for actin in aiding the repair of DNA breaks in human cells caused by carcinogens, UV light, and other mutagens.

Belin changed course for her postdoctoral work, in

Evolutionary geneticist Moises Exposito-Alonso joined the Department of Plant Biology as a staff associate in September 2019. He investigates whether and how plants will evolve to keep pace with climate change by conducting large-scale ecological and genome sequencing experiments. He also develops computational methods to derive fundamental principles of evolution, such as how fast natural populations acquire new mutations and how past climates shaped continental-scale biodiversity patterns. His goal is to use these first principles and computational approaches to forecast evolutionary outcomes of populations under climate change to anticipate potential future