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 extreme blooms. The bloom remerged in 2014 with a vengeance, and released toxins causing problems with the drinking water in Toledo, Ohio.

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An image of the algal blooms in Lake Erie taken in July 2015. NASA Earth Observatory images by Joshua Stevens, using Landsat data from the U.S. Geological Survey.
April 24, 2019

Washington, DC—Changes in temperature and precipitation have already impacted the amount of nitrogen introduced into U.S. waterways, according to new research from a team of three Carnegie ecologists published this week in Environmental Science & Technology.

Nitrogen from agriculture and other human activities washes into waterways, which, in excess, creates a dangerous phenomenon called eutrophication. This can lead to toxin-producing algal blooms or low-oxygen dead zones called hypoxia. Over the past several summers, dead zones and algal blooms in lake and coastal regions across the United States have received extensive news coverage.

Carnegie’s Anna

Anemone. California, Monterey Bay National Marine Sanctuary. Photographer: Dr. Dwayne Meadows, NOAA/NMFS/OPR.
March 28, 2019

Washington, DC—Tiny fragments of plastic in the ocean are consumed by sea anemones along with their food, and bleached anemones retain these microfibers longer than healthy ones, according to new research from Carnegie’s Manoela Romanó de Orte, Sophie Clowez, and Ken Caldeira.

Their work, published by Environmental Pollution, is the first-ever investigation of the interactions between plastic microfibers and sea anemones. Anemones are closely related to corals and can help scientists understand how coral reef ecosystems are affected by the millions of tons of plastic contaminating the world’s oceans.

One of the most-common types of plastics in the

Aerial view of red tide along Florida’s gulf coast - summer/fall 2018 by Ryan McGill, purchased form Shutterstock
February 26, 2019

Washington, DC—Strategies for limiting climate change must take into account their potential impact on water quality through nutrient overload, according to a new study from Carnegie’s Eva Sinha and Anna Michalak published by Nature Communications. Some efforts at reducing carbon emissions could actually increase the risk of water quality impairments, they found.

Rainfall and other precipitation wash nutrients from human activities like agriculture into waterways. When waterways get overloaded with nutrients, a dangerous phenomenon called eutrophication can occur, which can sometime lead to toxin-producing algal blooms or low-oxygen dead zones called hypoxia.

Subalpine forests of the Colorado Rockies are expected to be strongly affected by climate change. Photo courtesy of Lee Anderegg.
February 25, 2019

Washington, DC— On the mountain slopes of the western United States, climate can play a major role in determining which tree communities will thrive in the harshest conditions, according to new work from Carnegie’s Leander Anderegg and University of Washington’s Janneke Hille Ris Lambers.

Their findings, published in Ecology Letters, are an important step in understanding how forest growth will respond to a climate altered by human activity.

As researchers try to anticipate how climate change will affect forest ecosystems, it is crucial to understand the factors that influence how forest habitats change over time—including both environmental

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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.

Chris Field is a co-principal investigator of the Jasper Ridge Global Change Experiment at the Jasper Ridge Biological Preserve in northern California. The site, designed to exploit grasslands as models for understanding how ecosystems may respond to climate change, hosts a number of studies of the potential effects from elevated atmospheric carbon dioxide, elevated temperature, increased precipitation, and increased nitrogen deposition. The site houses experimental plots that replicate all possible combinations of the four treatments and additional sampling sites that control for the effects of project infrastructure. Studies focus on several integrated ecosystem responses to the

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

Monitoring tropical deforestation and forest degradation with satellites can be an everyday activity for non-experts who support environmental conservation, forest management, and resource policy development.

Through extensive observation of user needs, the Greg Asner team developed CLASlite ( the Carnegie Landsat Analysis System--Lite) to assist governments, nongovernmental organizations, and academic institutions with high-resolution mapping and monitoring of forests with satellite imagery.

CLASlite is a software package designed for highly automated identification of deforestation and forest degradation from remotely sensed satellite imagery. It incorporates state-of-the

Evolutionary geneticist Moises Exposito-Alonso joins the Department of Plant Biology as a staff associate in the summer of 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

Staff Associate Kamena Kostova joined the Department of Embryology in November 2018. She studies ribosomes, the factory-like structures inside cells that produce proteins. Scientists have known about ribosome structure, function, and biogenesis for some time. But, a major unanswered question is how cells monitor the integrity of the ribosome itself. Problems with ribosomes have been associated with diseases including neurodegeneration and cancer. The Kostova lab investigates the fundamental question of how cells respond when their ribosomes break down using mass spectrometry, functional genomics methods, and CRISPR genome editing.

Kostova received a B.S. in Biology from the

Sally June Tracy applies cutting-edge experimental and analytical techniques to understand the fundamental physical behavior of materials at extreme conditions. She uses dynamic compression techniques with high-flux X-ray sources to probe the structural changes and phase transitions in materials at conditions that mimic impacts and the interiors of terrestrial and exoplanets. She is also an expert in nuclear resonant scattering and synchrotron X-ray diffraction. She uses these techniques to understand novel behavior at the electronic level.  Tracy received her Ph.D. from the California Institute of

The Ludington lab investigates complex ecological dynamics from microbial community interactions using the fruit fly  Drosophila melanogaster. The fruit fly gut carries numerous microbial species, which can be cultured in the lab. The goal is to understand the gut ecology and how it relates to host health, among other questions, by taking advantage of the fast time-scale and ease of studying the fruit fly in controlled experiments.