The seasonal pattern of the carbon isotope content (δ13C) of atmospheric CO2 depends on local and nonlocal land‐atmosphere exchange and atmospheric transport. Previous studies suggested that the δ13C of the net land‐atmosphere CO2 flux (δsource) varies seasonally as stomatal conductance of plants responds to vapor pressure …
Journal: Journal Of Geophysical Research: Biogeosciences, Volume 122 (8): 1969-1987 (2017). DOI: https://doi.org/10.1002/2017JG003795 Sites: US-ARM, US-Ha1, US-Ho1, US-NR1, US-Wrc
Gross primary productivity (GPP) has been reported to increase with the fraction of diffuse solar radiation, for a given total irradiance. The correlation between GPP and diffuse radiation suggests effects of diffuse radiation on canopy light‐use efficiency, but potentially confounding effects of vegetation phenology have not been …
Journal: Journal Of Geophysical Research: Biogeosciences, Volume 121 (7): 1903-1915 (2016). DOI: http://doi.org/10.1002/2015JG003317 Sites: US-ARM
Journal: Nature Climate Change, Volume 6 (11): 1023-1027 (2016). DOI: 10.1038/nclimate3114 Sites: US-ARM, US-Bar, US-Blk, US-Blo, US-Bo1, US-Br3, US-Dk1, US-Dk2, US-Dk3, US-Fmf, US-FR2, US-Fuf, US-GLE, US-IB1, US-IB2, US-KFS, US-Kon, US-KS2, US-Me1, US-Me2, US-MMS, US-MOz, US-MRf, US-Ne1, US-Ne3, US-NR1, US-Oho, US-SRG, US-SRM, US-Syv, US-Ton, US-UMB, US-Var, US-WBW, US-WCr, US-Whs, US-Wkg
Biases in land‐atmosphere coupling in climate models can contribute to climate prediction biases, but land models are rarely evaluated in the context of this coupling. We tested land‐atmosphere coupling and explored effects of land surface parameterizations on climate prediction in a single‐column version of the National Center …
Journal: Journal Of Geophysical Research: Atmospheres, Volume 121 (20): 12,125-12,144 (2016). DOI: https://doi.org/10.1002/2016JD025223 Sites: US-ARM
The proliferation of digital cameras co‐located with eddy covariance instrumentation provides new opportunities to better understand the relationship between canopy phenology and the seasonality of canopy photosynthesis. In this paper we analyze the abilities and limitations of canopy color metrics measured by digital repeat photography …
Journal: Ecological Applications, Volume 25 (1): 99-115 (2015). DOI: http://doi.org/10.1890/14-0005.1 Sites: US-ARM, US-Bar, US-Ha1, US-Ho1, US-MMS, US-MOz, US-NR1, US-UMB, US-UMd, US-Var, US-Wrc
The Southern Great Plains are characterized by a fine-scale mixture of different land-cover types, predominantly winter-wheat and grazed pasture, with relatively small areas of other crops, native prairie, and switchgrass. Recent droughts and predictions of increased …
Journal: Agriculture, Ecosystems & Environment, Volume 213: 209-218 (2015). DOI: 10.1016/j.agee.2015.07.021 Sites: US-ARM
It is necessary to partition eddy covariance measurements of carbon dioxide exchange into its offsetting gross fluxes, canopy photosynthesis, and ecosystem respiration, to understand the biophysical controls on the net fluxes. And independent estimates of canopy photosynthesis (G) and ecosystem respiration (R) are needed to validate …
Journal: Agricultural and Forest Meteorology, Volume 207: 117-126 (2015). DOI: 10.1016/j.agrformet.2015.03.010 Sites: CA-Ca1, CA-Ca2, CA-Ca3, CA-Let, CA-Mer, CA-NS1, CA-NS3, CA-NS5, CA-NS6, CA-NS7, CA-Oas, CA-Obs, CA-Ojp, CA-Qcu, CA-Qfo, CA-SJ2, CA-SJ3, CA-TP4, CA-WP1, US-ARM, US-Aud, US-Bo1, US-Ho1, US-Ho2, US-IB2, US-KS2, US-MMS, US-MOz, US-NC2, US-NR1, US-SO2, US-SO3, US-SO4, US-SP2, US-SP3, US-SRM, US-Ton, US-Tw3, US-UMB, US-Var, US-WBW, US-Wkg, US-Wrc
he Weather Research and Forecasting (WRF) model is used to investigate choice of land surface model (LSM) on the near surface wind profile, including heights reached by multi-megawatt (MW) wind turbines. Simulations of wind profiles and surface energy fluxes were made using five LSMs of varying degrees of sophistication in dealing …
Journal: Atmosphere, Volume 6 (1): 21-49 (2014). DOI: http://doi.org/10.3390/atmos6010021 Sites: US-ARM
Recent advances in atmospheric transport model inversions could significantly reduce uncertainties in land carbon uptake through the assimilation of CO2 concentration measurements at weekly and shorter timescales. The potential of these measurements for reducing biases in estimated land carbon sinks depends on the strength of covariation …
Journal: Atmospheric Chemistry And Physics, Volume 14 (3): 1571-1585 (2014). DOI: http://doi.org/10.5194/acp-14-1571-2014 Sites: US-ARM
Journal: Journal Of Geophysical Research: Biogeosciences, Volume 119 (7): 1458-1473 (2014). DOI: 10.1002/2014JG002623 Sites: CA-Ca1, CA-Gro, CA-Let, CA-Oas, CA-Ojp, CA-Qfo, US-ARM, US-Dk3, US-Ha1, US-Ho1, US-IB2, US-Me2, US-MMS, US-MOz, US-Ne1, US-Ne2, US-Ne3, US-NR1, US-PFa, US-Syv, US-Ton, US-UMB, US-Var, US-WCr