Can humans alter climate change?

Researchers might be able to impact solar radiation effects but not for years

Can humans change the course of the environment? Seems like a stretch in many cases but scientists continue to look into the possibility of controlling greenhouse gases and reversing some of the toll of global warming.

One of the topics being explored is controlling the effects of solar radiation, according to a release on new research into the topic from Carnegie Institution for Science.  Ideas for solar radiation management include increasing the amount of aerosols in the stratosphere, which could scatter incoming solar heat away from Earth's surface, or creating low-altitude marine clouds to reflect these same rays. Clearly the size of the scale and the intricacies of the many atmospheric and climate processes make testing these ideas difficult, Carnegie stated.

More on climate technology: Federal climate change action? Not through this maze

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.

"While it is clearly premature to consider testing solar radiation management at a scale large enough to measure the climate response, it is not premature to understand what we can learn from such tests," said Doug MacMynowski of the California Institute of Technology, who led the research. "But we did not address other important questions such as the necessary testing technology and the social and political implications of such tests."

The researchers went on to say that they were able to demonstrate that smaller-scale tests of solar radiation management could help inform decisions about larger scale deployments. "Short-term tests would be particularly effective at understanding the effects of geoengineering on fast-acting climate dynamics. But testing would require several decades and, even then, would need to be extrapolated out to the centuries-long time scales relevant to studying climate change," the group said.

Some scientists have theorized that volcanic eruptions could stand in for tests, as they would cause same types of atmospheric changes as aerosols. But they wouldn't be as effective as a sustained test.

"No test can tell us everything we might want to know, but tests could tell us some things we would like to know," Caldeira said. "Tests could improve our understanding of likely consequences of intentional interference in the climate system and could also improve our knowledge about the climate's response to the interference caused by our carbon dioxide emissions."

The congressional watchdogs at the Government Accountability Office recently took a look at the current state of climate engineering science and technology.  Whereas carbon dioxide removal would reduce the atmospheric concentration of carbon dioxide (CO2), reducing greenhouse warming; and solar radiation management would either deflect sunlight before it reaches Earth or otherwise cool Earth by increasing the reflectivity of its surface or atmosphere. The GAO gathered experts' views of the future of U.S. climate engineering research and potential public responses to climate engineering.  Some of their key findings were that:

  • § Climate engineering technologies are not now an option for addressing global climate change, given our assessment of their maturity, potential effectiveness, cost factors, and potential consequences. Experts told us that gaps in collecting and modeling climate data, identified in government and scientific reports, are likely to limit progress in future climate engineering research.
  • § The majority of the experts consulted supported starting significant climate engineering research now. Advocates and opponents of research described concerns about its risks and the possible misuse of its results. Research advocates supported balancing such concerns against the potential for reducing risks from climate change. They further envisioned a future federal research effort that would emphasize risk management, have an international focus, engage the public and national leaders, and anticipate new trends and developments.
  • § A survey of the public suggests that the public is open to climate engineering research but is concerned about its possible harm and supports reducing CO2 emissions.

The GAO said seven solar radiation management technologies have been reported in sufficient detail for to assess them as candidates for climate engineering. Two would be deployed in the atmosphere-one scattering solar radiation back into space using stratospheric aerosols, the other reflecting solar radiation by brightening marine clouds. Two would be deployed in space-one scattering or reflecting solar radiation from Earth orbit, the other scattering or reflecting solar radiation at a stable position between Earth and the Sun. The three remaining technologies would artificially reflect additional solar radiation from Earth's surfaces-covered deserts, more reflective flora, or more reflective settled areas, according to the GAO.

Follow Michael Cooney on Twitter: nwwlayer8  and on Facebook

Layer 8 Extra

Check out these other hot stories:

DARPA offers $50,000 prize if you can figure out these shredded puzzles

FAA goes to the Web to fight lasers directed at aircraft battle

NASA: "Interplanetary bogeyman" comet Elenin is no more; it's an ex-comet

US to fund aggressive technology that cuts solar power costs 75%

Air Force wants to understand impact of automated systems the human psyche

After the iPhone, ex-Apple engineers built world's ultimate thermostat

IBM turns up Watson-like natural language healthcare analytics

New copper theft foil: Bust the drivers

Gartner: 16 long-held IT business practices you need to kill

Gartner: The top 10 strategic technology trends for 2012

Gartner: Big challenges lurk in building enterprise wireless networks

Gartner: 50% of Web sales will come via social, mobile apps by 2015

Gartner: 10 key IT trends for 2012

Join the Network World communities on Facebook and LinkedIn to comment on topics that are top of mind.

Copyright © 2011 IDG Communications, Inc.