Verifying greenhouse gas emissions

A National Academies panel led by Steve Pacala released a report in Spring of 2010 on the potential for monitoring global greenhouse emissions. Although countries can inventory their carbon dioxide emissions from fossil-fuel use accurately enough to support monitoring of an international climate change treaty, the panel found that currently there is no sufficiently accurate way to verify countries’ self-reported estimates using independent data, such as atmospheric measurements. However, the panel also found that strategic investments could be made within five years that would both improve self-reporting and yield a useful way to verify these estimates, reducing uncertainties about carbon dioxide emissions from fossil-fuel use and deforestation to less than 10 percent.

To overcome weaknesses in the current reporting system, the report advises the requirement of regular, rigorous reporting and review be extended to all countries, with the most stringent and accurate methods for calculating greenhouse gas emissions being used for the largest emissions sources in each country. The panel estimated that significant improvements in the accuracy of the inventories from 10 of the highest-emitting developing countries, such as China and India, could be achieved for approximately $11 million over five years.

The panel also determined that enabling independent verification of countries’ self-reported estimates will require additional atmospheric measurements and improved models to predict the movement of greenhouse gases in the atmosphere. To this end, the report recommends that new monitoring stations be established near cities and other large local emissions sources, and that the isotope carbon-14 should be measured in the carbon dioxide already collected at atmospheric sampling stations. Carbon-14, which is present in living organisms but not in fossil fuels, provides a way to discern whether carbon dioxide is generated from fossil-fuel or non-fossil-fuel sources. These additional analyses could be performed at a cost of approximately $5 million to $10 million per year.

The panel also recommended that NASA build and launch a replacement for the Orbiting Carbon Observatory (Figure 1), which failed at launch in February 2009. Such an observatory could monitor carbon dioxide emissions from cities and power plants and attribute them to individual countries; no other satellite has its critical combination of abilities, including high precision, a small footprint, and an ability to sense carbon dioxide near Earth’s surface.

Fig. 1. NASA’s Orbiting Carbon Observatory (OCO), which failed on launch in February 2009. The NAS committee determined that the satellite would have provided proof of concept for spaceborne technologies to monitor greenhouse gas emissions, as well as baseline emissions data. Image credit: NASA

Using these improved methods, fossil-fuel carbon dioxide emissions could be estimated by each country and checked using independent information with less than 10 percent uncertainty, the report says. The same is true for satellite-based estimates of deforestation, the largest source of carbon dioxide emissions after fossil-fuel use, and for growth of new forests, an important “sink” for reducing carbon dioxide.


America’s Climate Choices

A two-plus-year National Academy study called America’s Climate Choices has been completed and will soon be published. Rob Socolow was a member of the Committee on America’s Climate Choices, the parent committee for this study. The questions posed in this process were:

  • What short-term actions can be taken to respond effectively to climate change?
  • What promising long-term strategies, investments, and opportunities could be pursued to respond to climate change?
  • What are the major scientific and technological advances needed to better understand and respond effectively to climate change?
  • What are the major impediments to responding effectively to climate change, and what can be done to overcome these impediments?

The forthcoming report of the Committee on America’s Climate Choices will urge that climate change be viewed through the lens of iterative risk management. It will discuss the coordination of initiatives in the private sector and various levels of government, and will call for the integration of climate science in the planning for adaptation.


Negative emissions through direct air capture of CO2

Rob Socolow co-chaired a committee of the American Physical Society that has produced a report on direct air capture of CO2 (DAC) by chemicals. Direct air capture can be accomplished with existing technologies, but the actual cost of deploying DAC at large scale, and the feasibility of scaling up quickly, have been controversial. The APS report will provide an estimate of the cost of large-scale capture of CO2 from the air using costing methodologies typically used in industry, offer insight into the challenges of scale-up, and outline areas of emerging research that might lead to reduced costs in the future. The report should appear in the spring of 2011.


New online data visualization application – one billion high emitters

A new online data visualization tool that illustrates the “One Billion High Emitters” concept is now available on the CMI website. Shoibal Chakravarty spearheaded the effort to develop the tool, with which visitors can view current and projected distributions of carbon emissions by region, choose a future emissions target, and view the contributions various regions would make to cutting carbon emissions based on the number of high emitters in each country. The section of the website that highlights the high emitters concept received over 1200 unique visitors in 2010, and the group is currently exploring strategies to encourage use of the visualization tool in classrooms.


Stabilization Wedges

The Stabilization Wedges concept continues to pique popular interest. CMI continues to receive regular requests to reproduce wedge graphics in both academic and lay publications, and Roberta Hotinski continues to facilitate workshops for teachers. This year, the National Energy Education Development Project (NEED) has completed development of a climate curriculum with a strong emphasis on the wedges and has run pilot workshops with teachers to obtain feedback on the content. The materials will be finalized this spring but preliminary copies are now available for download from the NEED website: