1994-5								February 11, 
1994

Contact:  Joan Vandiver Frisch
Manager, NCAR Media Relations, Boulder, CO 
Tel: 303-497-8607;  E-mail: jfrisch@ncar.ucar.edu

NCAR Granted Patent for Trace Gas Sampling Equipment

Methane, a "greenhouse" gas is produced by both natural and 
manmade sources. Climate modelers need to know how much 
methane is being produced by the 1.25 billion cattle throughout the 
world who "belch" it into the atmosphere.  The enclosed press release 
is an announcement about a patent for a device that will measure how 
much methane is being produced by cows in a form of a harmless 
cowbell-type receptacle attached to the cow's leather harness, without 
impeding its feeding or walking.  Cattle are among the top three 
sources of atmospheric methane, but the amount of methane they 
produce depends upon the amount and type of food they eat.  This 
device will measure those variations in cows on differing types of diets.  
The other two major sources of methane are rice paddies and natural 
swamps and marshes.  

A patent for a novel system of measuring metabolic gases, such as 
methane, from cattle has been issued by the U. S. Patent Office to 
Patrick Zimmerman, a senior scientist at the National Center for 
Atmospheric Research (NCAR) in Boulder, Colorado.  Cattle are 
thought to be a significant source of methane, which is believed to 
contribute to a gradual global warming as it accumulates in the earth's 
atmosphere.  

Zimmerman's invention consists of a cowbell-sized, stainless steel 
canister,  attached to a cow halter.  A sample line runs from the canister 
to the animal's mouth.  The cow is fed a capsule that releases a volatile 
tracer gas at a known rate.  Since the tracer gas is emitted through the 
cow's mouth in the same way that metabolic gases (such as methane) 
are released, scientists can use the tracer to calculate the rate of 
methane emission.  First envisioned by Zimmerman, the device 
enables scientists to monitor the amount of methane that cattle and 
other ruminants emit into the atmosphere without confining the 
animals in a stall or other artificial environment.

The present form of the apparatus was developed by Halvore Westberg, 
an NCAR affiliate scientist, and his colleague, Kristen Johnson, both 
research scientists at Washington State University.  A description and 
diagram of the device appears in the February issue of Environmental 
Science and Technology.  The University Corporation for Atmospheric 
Research (UCAR) Foundation is pursuing licensing opportunities and 
has applied for patents in Argentina, Australia, New Zealand and 
Europe.  NCAR is sponsored by the National Science Foundation and 
managed by UCAR, a consortium of 61 universities with Ph.D. 
programs in the atmospheric or related sciences.  

(Full-page diagram of the cutaway view of cow and apparatus available 
by request if you send us your fax no.)