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Katharine Gebbie Speech: Greenhouse Gas Emissions Quantification and Verification Strategies Workshop

Thank you and welcome.

The National Institute of Standards and Technology initiated this workshop to provide an opportunity for you, our customers and stakeholders, to lay out both the needs and the opportunities for accurate quantification of greenhouse gas (GHG) emissions. This workshop is the second in a series of "NIST External Needs Assessment Workshops" intended to focus on problems that are important to you.

Scripps is a natural partner for NIST in the effort to quantify and verify GHG emissions because of their long commitment to monitoring and characterizing the Earth's climate.

  • Charles Keeling's well-known Curve, which shows a steady yearly increase in atmospheric carbon dioxide levels, is an exceptional record – primarily because of its firm grounding and close attention to measurement accuracy and standards over a long period.
  • This work continues today at Scripps, undertaken by outstanding research scientists some of whom have been instrumental in the planning of this workshop, and I would like to thank Ray Weiss and Ralph Keeling in particular for their efforts in this regard.
  • I would also like to thank Tony Hayment, the Director of Scripps, and his staff led by Kathleen Ritzman, who have been critical in the planning and conduct of the workshop.


So on behalf of both NIST and Scripps, we're glad you have come to our gathering, because we need your help. The whole planet does.


So far, we've been looking at the Earth's climate with somewhat blurry vision. But even with blurry vision, it's more than clear that we're in a bad place.

  • Sea ice is shrinking, permafrost is thawing, glaciers are disappearing. And the primary cause of these changes is the emission of GHGs from our factories, power plants and vehicles.1
  • Work begun by Charles Keeling of Scripps in 1957 indicates that the level of carbon dioxide in the atmosphere has climbed from 315 parts per million to nearly 390 in half a century. This GHG accounts for more than half the temperature rise caused by human activity.2
  • We are also releasing other gases – methane, nitrous oxide, sulfur hexafluoride – into the atmosphere that trap heat more effectively than CO2.


In December of last year, John Holdren, the President's Science Advisor, pointed out some of the effects we have already observed in his testimony before Congress's Select Committee on Energy and Global Warming:


  • The United States has been experiencing an increase in the severity of floods, droughts, and heat waves, with consequences for human life and health, property, and agriculture.3
  • The strongest hurricanes appear to be increasing in number and power in a pattern correlated with rising sea-surface temperatures in the regions that spawn these storms.
  • Global-average sea level has risen roughly 8 inches over the last century; the consequence has been increased losses to beach erosion and storm damage in heavily populated coastal areas.


Scientists have tried to determine long-term climate essentially by repurposing satellites and weather stations. But these are best at observing short-term changes. So it's a less than a perfect fit.


But for the first time in history, we are now attempting to create a generation of dedicated climate scientists and the greenhouse gas monitoring instruments necessary to this research. These instruments should allow scientists to figure out just where greenhouse gases are coming from, and the "sinks" where some of these gases are being absorbed.

We in this room are in an ideal position to define how accurately these new instruments should be monitoring greenhouse gas fluxes. So over the course of the next two days, I hope you will have a vigorous and frank discussion about the best ways of doing that.

Why does NIST and the rest of the planet need you to talk this over? Because one thing is certain even before we begin: What we monitor will have to be measured, and measured accurately over long time periods.

  • Without agreement on what is happening to our climate, there can be no agreement on what should be done. Every nation involved in GHG monitoring needs to agree that – for example – a measurement taken in San Diego in 1990 can be compared usefully to one taken in Sumatra in 2020.
  • Accuracy must improve. To take another example, weather prediction requires temperature to be measured to within half a degree F. But to perceive the differences in temperature that reflect climate change over the course of a decade, requires roughly ten times that level of accuracy. We need a correspondingly high level of accuracy when making GHG measurements.
  • The world economy also needs this accuracy in the near term. If a greenhouse gas credit system is ever to become effective, it will require accurate measurement to determine the quantity of material being traded, just as with any commodity, from sugar to steel.


In short, we need standards: standards that are traceable to the International System of Units, the so-called SI which includes the meter and kilogram. We need recommendations about how best to make accurate measurements of greenhouse fluxes from sources and into sinks.


To get started we've included five breakout sessions in today's workshop, one each is dedicated to a major contributing factor in atmospheric GHG levels.

  • Two sessions concern the sources of GHGs: combustion processes in industry, power plants and local sources such as personal vehicles and livestock emissions. Quantifying what we are putting in to the air is of course a major goal of any emissions reduction program.
  • A third concerns natural and man-made sinks that remove carbon from the air: Among these are forests, grasslands and farms.
  • The fourth and fifth cover other critical issues that need to be addressed. One regards the best ways to measure emissions remotely – from satellites and land-based monitoring stations. The other aims to ensure a viable, effective system of verifying international compliance with any agreements on emissions control that is based on quantification methods of sufficient accuracy.


When you meet in your breakout sessions, a great number of questions need answering. A few of these:


  • If the community decides a market-based approach to reduction is the best option, then trust and confidence in those markets is needed. A ton of emissions should require a ton of offsets, but what level of accuracy is needed to support that confidence?
  • Even more fundamentally, how does one identify the factors needed to determine the carbon footprint in a specific case?
  • Perhaps most critically: How can we effectively integrate information across different sectors of society? And how can we be sure that we have sufficiently overcome uncertainty about GHG's to ensure that we know the truth about what is happening?


Answering these questions by the end of the workshop is only the first step in the learning process. We will use the results to inform our strategic decision making in a report, tentatively titled the "Opportunities Document", to be prepared by the end of the summer. The NIST Visiting Committee on Advanced Technology will release the result, which we hope will inform planning activities at the technical level.  Our aim is for it to become a vehicle for partnership building, communications, and acceleration of the most critical measurement solutions. 


With this goal in mind, we look forward to your input.


1 U.S. Global Change Research Program's "Global Climate Change Impacts in the United States" (Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, eds., Cambridge University Press, 2009), and UN Environment Program's "Climate Change Science Compendium" C.P. McMullen and J. Jabbour, eds., UNEP, 2009).

2 Data from Charles Keeling's Curve

3 Bullet points drawn from testimony delivered by John P. Holdren, Director of OSTP, before the House Select Committee on Energy Independence and Global Warming on December 2, 2009. (This testimony also draws from reports in footnote 1.)

Created June 11, 2010, Updated December 29, 2016