Weak Northern and Strong Tropical Land Carbon Uptake from Vertical Profiles of Atmospheric CO 2

• DOI: 10.1126/science.1137004
• Publication Date: 2007-06-21T21:41:47Z
• Authors: Britton B. Stephens; Kevin R. Gurney; Pieter P. Tans; Colm Sweeney; Wouter Peters; Lori Bruhwiler; Philippe Ciais; Michel Ramonet; Philippe Bousquet; Takakiyo Nakazawa; Shuji Aoki; Toshinobu Machida; Gen Inoue; Nikolay Vinnichenko; Jon Lloyd; Armin Jordan; Martin Heimann; Olga Shibistova; Ray L. Langenfelds; L. Paul Steele; Roger J. Francey; A. Scott Denning
• Keywords: Carbon fibers; Terrestrial ecosystem; Atmospheric carbon cycle

Measurements of midday vertical atmospheric CO 2 distributions reveal annual-mean gradients that are inconsistent with models estimate a large transfer terrestrial carbon from tropical to northern latitudes. The three most closely reproduce the observed weaker uptake –1.5 petagrams per year (Pg C –1 ) and emission +0.1 Pg compared previous consensus estimates –2.4 +1.8 , respectively. This suggests industrial emissions plays smaller role than previously thought that, after subtracting land-use emissions, ecosystems may currently be strong sinks for .