ARL News

NOAA to participate in an upcoming test with the CTBTO

November 30, 2007

The Comprehensive Test Ban Treaty Organization (CTBTO) will be conducting an exercise with the World Meteorological Organization’s (WMO) Regional Specialized Meteorological Centers (RSMC) next month to test the operational arrangements to provide potential source locations based upon an anomalous radiological measurement in their network. The intent of their monitoring network is to identify the source of clandestine nuclear testing based upon any radiological products that may be emitted to the atmosphere and then the RSMC would compute the upwind path that would have carried the material to the monitoring location. The Air Resources Laboratory (ARL) will exercise the prototype source attribution tools it has developed to support the services of the U.S. RSMC.


The Air Resources Laboratory (ARL) has been providing research support to the development of source-attribution capabilities that can be used in the context of the CTBTO applications since 1995 when the CTBTO was first being established. The framework of the cooperation agreement between CTBTO and WMO was formalized in July 2003 and under these arrangements CTBTO notifies the WMO Secretariat and RSMC designated for the provision of atmospheric backtracking products when anomalous Radionuclide measurements occur in the International Monitoring System. The RSMC provide upwind transport model products to the CTBTO that identify the source regions for the measurements. The CTBTO then synthesizes these multiple products into a single event report for distribution to its member countries. NOAA’s RSMC for transport model products is a joint activity between the National Centers for Environmental Prediction (NCEP) and ARL, with NCEP providing operational support and ARL providing the research and development support. This upcoming test and all previous tests have been conducted in our research environment. However, at the completion of this next test, WMO will request its RSMC to consider providing these products in more operational framework.


The CTBT is intended to limit nuclear proliferation by restricting the testing of nuclear weapons. The treaty includes verification approaches to discourage clandestine tests. The identification of sources of airborne radioactive is an important component of the verification.

More Information:

Contact information:
Roland R. Draxler
Phone: (301) 713-0295 x134