Carnegie Science News - Department of Global Ecology

Thursday, February 16, 2012
Only the lowest CO2 emitting technologies can avoid a hot end-of-century

Could replacing coal-fired electricity plants with generators fueled by natural gas bring global warming to a halt in this century? What about rapid construction of massive numbers of solar or wind farms, hydroelectric dams, or nuclear reactors—or the invention of new technology for capturing the carbon dioxide produced by fossil-fueled power plants and storing it permanently underground? Nathan Myhrvold of Intellectual Ventures teamed up with Carnegie Institution’s Ken Caldeira to calculate the expected climate effects of replacing the world’s supply of electricity from coal plants with any of eight cleaner options.

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Tuesday, February 14, 2012
Super High-Resolution Carbon Estimates for Endangered Madagascar

By combining airborne laser technology, satellite mapping, and ground-based plot surveys, a team of researchers has produced the first large-scale, high-resolution estimates of carbon stocks in remote and fragile Madagascar. The group has shown that it is possible to map carbon stocks in rugged geographic regions and that this type of carbon monitoring can be successfully employed to support conservation and climate-change mitigation under the United Nations initiative on Reduced Emissions from Deforestation and Degradation (REDD).

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Monday, January 23, 2012
Geoengineering and global food supply

Carbon dioxide emissions from the burning of coal, oil, and gas have been increasing over the past decades, causing the Earth to get hotter and hotter. There are concerns that a continuation of these trends could have catastrophic effects, including crop failures in the heat-stressed tropics. This has led some to explore drastic ideas for combating global warming, including the idea of trying to counteract it by reflecting sunlight away from the Earth. However, it has been suggested that reflecting sunlight away from the Earth might itself threaten the food supply of billions of people. New research led by Carnegie’s Julia Pongratz examines the potential effects that geoengineering the climate could have on global food production and concludes that sunshade geoengineering would be more likely to improve rather than threaten food security.

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Thursday, December 22, 2011
Sea Cucumbers: Dissolving coral reefs?

Coral reefs are extremely diverse ecosystems that support enormous biodiversity. But they are at risk. Carbon dioxide emissions are acidifying the ocean, threatening reefs and other marine organisms. New research led by Carnegie’s Kenneth Schneider analyzed the role of sea cucumbers in portions of the Great Barrier Reef and determined that their  dietary process of dissolving calcium carbonate (CaCO3) from the surrounding reef accounts for about half of at the total nighttime dissolution for the reef.

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Monday, December 12, 2011
The case of the dying aspens

Over the past 10 years, the death of forest trees due to drought and increased temperatures has been documented on all continents except Antarctica. This can in turn drive global warming by reducing the amount of carbon dioxide removed from the atmosphere by trees and by releasing carbon locked up in their wood. New research led by Carnegie researcher and Stanford University PhD student William Anderegg offers evidence for the physiological mechanism governing tree death in a drought.

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Wednesday, November 16, 2011
Scientists Tackle the Carbon Conundrum

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Scientists, including Carnegie's Anna Michalak, have developed a new, integrated, ten-year science plan to better understand the details of Earth’s carbon cycle. It identifies new research areas such as the role of humans as agents and managers of carbon cycling and climate change, the direct impact of greenhouse gases on ecosystems including changes to plant and animal diversity and ocean acidification, the need to address social concerns, and how best to communicate results to the public and decision makers.

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Wednesday, October 26, 2011
Testing geoengineering

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Solar radiation management is a class of theoretical concepts for manipulating the climate in order to reduce the risks of global warming caused by greenhouse gasses. But its potential effectiveness and risks are uncertain, and it is unclear whether tests could help narrow these uncertainties. A team composed of Caltech's Doug MacMynowski, Carnegie’s Ken Caldeira and Ho-Jeong Shin, and Harvard's David Keith used modeling to determine the type of testing that might be effective in the future.

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Monday, October 17, 2011
Links in the chain: Global carbon emissions and consumption

With Video

It is difficult to measure accurately each nation’s contribution of carbon dioxide to the Earth’s atmosphere. Carbon is extracted out of the ground as coal, gas, and oil, and these fuels are often exported to other countries where they are burned to generate the energy that is used to make products. In turn, these products may be traded to still other countries where they are consumed. A team led by Carnegie’s Steven Davis, and including Ken Caldeira, tracked and quantified this supply chain of global carbon dioxide emissions.

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Wednesday, September 14, 2011
Water evaporated from trees cools global climate

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Scientists have long debated about the impact on global climate of water evaporated from vegetation. New research from Carnegie’s Global Ecology department concludes that evaporated water helps cool the earth as a whole, not just the local area of evaporation, demonstrating that evaporation of water from trees and lakes could have a cooling effect on the entire atmosphere. These findings have major implications for land-use decision making.

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Tuesday, July 26, 2011
Reforestation’s Cooling Influence--A Result of Farmer’s Past Choices

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Decisions by farmers to plant on productive land with little snow enhances the potential for reforestation to counteract global warming, concludes new research from Carnegie’s Julia Pongratz and Ken Caldeira. Previous research has led scientists and politicians to believe that regrowing forests on Northern lands that were cleared in order to grow crops would not decrease global warming. But these studies did not consider the importance of the choices made by farmers in the historical past.

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