Mid-afternoon CO and CH4 from NOAA Tall Tower NetworkSummer 2007

TEXAS MAINE WISCONSIN COLORADO IOWA

CO

, p

pb

CO

CH

4,

pp

b

CH4

WBI (West Branch, Iowa): •Instrumentation was installed on the KWKB-TV tower in late June 2007. •Samples agricultural ecosystems. •Summertime CO2 levels in this region are among the lowest in North America due to strong uptake by corn and other crops. •We expect to see interannual variability in the CO2 seasonal cycle that is related to crop yields, which are carefully tracked.

•For example, 2007 is expected to be a record corn crop, as demand has increased for production of biofuels.

•Partner: University of Iowa (Charles Stanier)

BAO (Erie, Colorado): •Located on the Boulder Atmospheric Observatory (BAO) tower, which has been operated by the ESRL Physical Sciences Division (PSD) since the 1970s. •Instrumentation for in situ monitoring of CO2 and CO was installed in April 2007. •Automated flask sampling equipment installed August 2007•Targets urban and industrial sources of CO2 as well as upwind mountain ecosystems

Tail pipe of North America

Colm Sweeney, NOAA/ESRLWade McGillis, Columbia University

Pieter Tans, NOAA/ESRL