Livermore researchers determine biosphere unaffected by geoengineering schemes

December 19, 2002

LIVERMORE, Calif. -- Using models that simulate the interaction between global climate and land ecosystems, atmospheric scientists from the Lawrence Livermore National Laboratory have shown that compensating for the carbon dioxide "greenhouse effect" by decreasing the amount of sunlight reaching the planet (geoengineering) could create a more vigorous ecosystem while helping to curb global warming.

The study suggests that planetary-scale engineering projects to lessen the amount of solar radiation reaching the Earth's surface will likely do little to prevent the effects of increased greenhouse gases on the terrestrial biosphere. In fact, plants could experience growth spurts.

In a paper entitled: "Impact of Geoengineering Schemes on the Terrestrial Biosphere," Livermore researchers Bala Govindasamy, Starley Thompson, Philip Duffy, Ken Caldeira and University of Wisconsin collaborator Christine Delire, modeled the impact on Earth's land biosphere due to various schemes that would reduce the amount of sunlight reaching the planet's surface. The research appears in the Nov. 26 online edition of Geophysical Research Letters.

"Our models show plant life getting a big boost from the carbon dioxide fertilization when atmospheric CO2 levels are doubled due to anthropogenic fossil fuel emissions," Govindasamy said. "We noticed that in a CO2-enriched world, the terrestrial biosphere was largely unaffected by decreases in surface solar radiation by a couple of percentage points through various geoengineering schemes."

In earlier research, scientists have maintained that greenhouse gases emitted from the burning of fossil fuels are one of the largest sources of global warming because they cause an increase in the amount of carbon dioxide in the atmosphere. Methods to reduce atmospheric carbon dioxide vary from storing it in the deep ocean to reducing the amount of sunlight reaching the planet (geoengineering) that could largely counteract the warming influence of more greenhouse gases.

"Critics suggested that 'turning down the sun' could harm terrestrial ecosystems that depend on light for photosynthesis, but this new work shows that a change in solar flux to stabilize climate would have little effect on the terrestrial biosphere," Caldeira said. "In fact, turning down the sun a bit reduces evaporation and therefore gives the plants more water for photosynthesis so that they may actually grow better in a geoengineered world than they do today."

The researchers, however, strongly caution against adopting any geoengineering scheme because "there are many reasons why geoengineering is not a preferred option for climate stabilization." Among these are the risks of system failure and unpredictable responses of Earth's climate system to large-scale human intervention ecosystems.

"First, geoengineering schemes impose a variety of technical, political and economic challenges. International consensus to develop and maintain the schemes would be difficult. Failure of a scheme could be catastrophic," said Govindasamy said. "CO2 fertilization could impact ecosystem goods and services not represented by our land biosphere model, such as plant species abundance and competition, habitat loss, biodiversity and other disturbances."

The LLNL-led group used a general circulation model coupled to a model of land vegetation to conclude that the change in solar flux needed to stabilize climate would have little effect on net primary productivity in land.
-end-
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy's National Nuclear Security Administration.

DOE/Lawrence Livermore National Laboratory

Related Greenhouse Gases Articles from Brightsurf:

Mitigation of greenhouse gases in dairy cattle through genetic selection
Researchers in Spain propose mitigating methane production by dairy cattle through breeding.

Researchers control cattle microbiomes to reduce methane and greenhouse gases
''Now that we know we can influence the microbiome development, we can use this knowledge to modulate microbiome composition to lower the environmental impact of methane from cows by guiding them to our desired outcomes,'' Ben-Gurion University of the Negev Prof Mizrahi says.

A new look into the sources and impacts of greenhouse gases in China
Special issue of Advances in Atmospheric Sciences reveals new findings on China's GHG emissions and documents changes in local and regional environments.

New catalyst recycles greenhouse gases into fuel and hydrogen gas
Scientists have taken a major step toward a circular carbon economy by developing a long-lasting, economical catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas, and other chemicals.

Making microbes that transform greenhouse gases
A new technique will help not only reduce greenhouse gas emissions, but the potential to reduce the overall dependence on petroleum.

Reducing greenhouse gases while balancing demand for meat
Humans' love for meat could be hurting the planet. Many of the steps involved in the meat supply chain result in greenhouse gas emissions.

White people's eating habits produce most greenhouse gases
White individuals disproportionately affect the environment through their eating habits by eating more foods that require more water and release more greenhouse gases through their production compared to foods black and Latinx individuals eat, according to a new report published in the Journal of Industrial Ecology.

Degrading plastics revealed as source of greenhouse gases
Researchers from the University of Hawai'i at Mānoa School of Ocean and Earth Science and Technology (SOEST) discovered that several greenhouse gases are emitted as common plastics degrade in the environment.

What natural greenhouse gases from wetlands and permafrosts mean for Paris Agreement goals
Global fossil fuel emissions would have to be reduced by as much as 20 percent more than previous estimates to achieve the Paris Agreement targets, because of natural greenhouse gas emissions from wetlands and permafrost, new research has found.

Greenhouse gases were the main driver of climate change in the deep past
Greenhouse gases were the main driver of climate throughout the warmest period of the past 66 million years, providing insight into the drivers behind long-term climate change.

Read More: Greenhouse Gases News and Greenhouse Gases Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.