October, 2005

(L-R) Dr. Hans R. Friedli (NCAR) and Dr. Larry Radke (NCAR/UW) are PI's conducting atmospheric Mercury research in the Seattle area. Mercury (Hg), a powerful neurologic and mutagenic poison, is the only metal with significant vapor pressure at STP. Hg is ubiquitously present in our environment at low concentrations. Unfortunately, biologic and hydrologic processes, that are poorly understood, can concentrate Hg more than a million times, where it becomes a threat to humans. This research is made more difficult because there are many natural and anthropogenic sources of toxic atmospheric mercury about which little are known. Recently, Friedli and Radke found that, surprisingly, forest fires efficiently liberate mercury from both forest fuels and soils. This unexpectedly large Hg source is globally important in our studies to understand the cycles of various mercury sources through the environment. Now the team is custom-instrumenting a turbocharged twin Super Skymaster aircraft to study airborne aspects of the atmospheric transformation of naturally emitted Hg for the Electric Power Research Institute! The Mt. St. Helen’s plume is a particular target for this research which, we suspect, may be rich in Gaseous Elemental Mercury (GEM), says Dr. Larry Radke. The Institute for Airborne Research (IfAR), a Paine Field based corporation is providing the aircraft and a full-service contract support for this research, says Robert Eatwell, General Manager.

July, 2005

These instruments were designed by (L-R) Dean Hegg and David Covert and assembled by Steven Domonkos. They were installed in the US Navy's Twin Otter research aircraft for CARMA III project and were flown over the Pacific, off the coast of Monterey CA. There they studied the impact of sea surface temperature and aerosols on cloud microphysical properties. Katie Crahan also participated in the study, flying on the Twin Otter and played a major role in aerosol data analysis.

The instrumentation package shown here in the top photo consists of two distinct instruments. On the right is a humidigraph, designed to measure the change in aerosol light scattering coefficient as a function of relative humidity - a key parameter in radiative forcing calculations. On the left is an aerosol hydration spectrometer that measures the change in aerosol particle sizes as a function of relative humidity. This change is a function of chemical composition and is the link between aerosol composition and the impact of aerosols on radiative transfer. For more information on the Twin Otter research aircraft and the CARMA III project go to: CIRPAS

July, 2004

The people pictured in top photo are (L-R): David Covert, Norm Ahlquist, Steven Domonkos, Sarah Doherty and Berko Sierau. They are standing in front of a pod that will mount on the end of the port wing of the NOAA P3-B research aircraft. The P3 is being deployed to Portsmouth, New Hampshire for the NorthEast AirQuality study/Intercontinental Transport and Chemical Transport 2004 (NEAQS/ITCT-2k4) experiment from July 1 - August 15.

The instruments that these scientists packed in the pod will measure light scattering and absorption by aerosol particles. The data will be combined with other measurements of aerosol chemical and microphysical properties, gas species concentrations and meteorological data to investigate the suspected primary pollution source regions in the Ohio region and along the eastern seaboard. This data can be used to understand both the air quality and climate impacts of the pollutants.

In addition, the P3 flights will be coordinated with measurement on other platforms deployed by NOAA, NASA, the Office of Naval Research, and various universities and air quality agencies in both the U.S. and Europe so that the transport and transformation of the pollution emissions can be tracked as they are advanced across New England and the North Atlantic to western Europe.