title: Consistent land- and atmosphere-based U.S. carbon sink estimates.
abstract: For the period 1980-89, we estimate a carbon sink in the coterminous United States between 0.30 and 0.58 petagrams of carbon per year (petagrams of carbon = 10(15) grams of carbon). The net carbon flux from the atmosphere to the land was higher, 0.37 to 0.71 petagrams of carbon per year, because a net flux of 0.07 to 0.13 petagrams of carbon per year was exported by rivers and commerce and returned to the atmosphere elsewhere. These land-based estimates are larger than those from previous studies (0.08 to 0.35 petagrams of carbon per year) because of the inclusion of additional processes and revised estimates of some component fluxes. Although component estimates are uncertain, about one-half of the total is outside the forest sector. We also estimated the sink using atmospheric models and the atmospheric concentration of carbon dioxide (the tracer-transport inversion method). The range of results from the atmosphere-based inversions contains the land-based estimates. Atmosphere- and land-based estimates are thus consistent, within the large ranges of uncertainty for both methods. Atmosphere-based results for 1980-89 are similar to those for 1985-89 and 1990-94, indicating a relatively stable U.S. sink throughout the period.
authors: Department of Ecology and Evolutionary Biology, Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ 08544, USA. Pacala@princeton.edu
authors: S W
authors: SW
authors: Pacala
authors: G C
authors: GC
authors: Hurtt
authors: D
authors: D
authors: Baker
authors: P
authors: P
authors: Peylin
authors: R A
authors: RA
authors: Houghton
authors: R A
authors: RA
authors: Birdsey
authors: L
authors: L
authors: Heath
authors: E T
authors: ET
authors: Sundquist
authors: R F
authors: RF
authors: Stallard
authors: P
authors: P
authors: Ciais
authors: P
authors: P
authors: Moorcroft
authors: J P
authors: JP
authors: Caspersen
authors: E
authors: E
authors: Shevliakova
authors: B
authors: B
authors: Moore
authors: G
authors: G
authors: Kohlmaier
authors: E
authors: E
authors: Holland
authors: M
authors: M
authors: Gloor
authors: M E
authors: ME
authors: Harmon
authors: S M
authors: SM
authors: Fan
authors: J L
authors: JL
authors: Sarmiento
authors: C L
authors: CL
authors: Goodale
authors: D
authors: D
authors: Schimel
authors: C B
authors: CB
authors: Field
mesh_terms: D000383:Agriculture; D001272:Atmosphere; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide; D003247:Conservation of Natural Resources; D017753:Ecosystem; D005390:Fires; D016468:Forestry; D012987:Soil; D013997:Time Factors; D014197:Trees / Q000378:metabolism; D014481:United States; D014934:Wood
chemical_list: D012987:Soil; D002245:Carbon Dioxide; D002244:Carbon