Green Ocean Amazon 2014/15 ??? Scaling Amazon Carbon Water Couplings Field Campaign Report

Dubey, Manvendra²  Parket, Harrison²  Myers, Katherine²  Rahn, Thom²  Christoffersson, B.²  Wunch, Debra³  Wennberg, Paul³ 

[1] Pacific Northwest National Laboratory;Los Alamos National Lab. (LANL), Los Alamos, NM (United States);California Inst. of Technology (CalTech), Pasadena, CA (United States)

关键词: Amazon;    rainforest carbon cycle;    Fourier Transform Spectrometer;    trace gas column tropical ecosystem carbon cycle models;    evapotranspiration;   

DOI  :  10.2172/1302243
RP-ID  :  DOE/SC--ARM-16-044
PID  :  OSTI ID: 1302243

学科分类：环境科学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

Forests soak up 25% of the carbon dioxide (CO2) emitted by anthropogenic fossil energy use (10 Gt C y-1), moderating its atmospheric accumulation. How this terrestrial CO2 uptake will evolve with climate change in the 21st Century is largely unknown. Rainforests are the most active ecosystems, with the Amazon basin storing 120 Gt C as biomass and exchanging 18 Gt C y-1 of CO2 via photosynthesis and respiration and fixing carbon at 2-3 kg C m-2 y-1. Furthermore, the intense hydrologic and carbon cycles are tightly coupled in the Amazon where about half of the water is recycled by evapotranspiration and the other half imported from the ocean by Northeasterly trade winds. Climate models predict a drying in the Amazon with reduced carbon uptake while observationally guided assessments indicate sustained uptake. We set out to resolve this huge discrepancy in the size and sign of the future Amazon carbon cycle by performing the first simultaneous regional-scale high-frequency measurements of atmospheric CO2, H2O, HOD, CH4, N2O, and CO at the T3 site in Manacupuru, Brazil, as part of DOE's GoAmazon 2014/15 project. Our data will be used to inform and develop DOE's Community Land Model (CLM) on the tropical carbon-water couplings at the appropriate grid scale (10-50 km). Our measurements will also validate the CO2 data from Japan's Greenhouse gases Observing Satellite (GOSAT) and NASA's Orbiting Carbon Observatory (OCO)-2 satellite (launched in July, 2014). Our data addresses these science questions: 1. How does ecosystem heterogeneity and climate variability influence the rainforest carbon cycle? 2. How well do current tropical ecosystem models simulate the observed regional carbon cycle? 3. Does nitrogen deposition (from the Manaus, Brazil, plume) enhance rainforest carbon uptake?