Article : A preliminary investigation of boundary layer effects on daytime atmospheric CO2 concentrations at a mountaintop location in the Rocky Mountains
Authors : Shapiro, A.School of Meteorology, University of Oklahoma, Norman, Oklahoma, USA, email@example.com, Axelsen, S. L.IMAU, Utrecht University, Utrecht, The Netherlands, firstname.lastname@example.org, Axelsen, S. L.IMAU, Utrecht University, Utrecht, The Netherlands, email@example.com, Steeneveld, G. J.Department of Meteorology and Air Quality,Wageningen University, Wageningen, The Netherlands, firstname.lastname@example.org, Martínez, D.Departament de Física, Universitat de les Illes Balears, Mallorca, Spain, email@example.com, De Wekker, S. F. J.Department of Environmental Sciences, University of Virginia, Charlottesville, VA, USAInstitute, Steamboat Springs, CO, USA, firstname.lastname@example.org,
Abstract : Observations of CO2 concentration at a mountaintop in the Colorado Rockies in summer show a large diurnal variability with minimum CO2 concentrations found between 10:00 and 18:00 MST. Simulations are performed with a mesoscale model to examine the effects of atmospheric structure and large-scale flows on the diurnal variability. In the simulations initialized without large-scale winds, the CO2 minimum occurs earlier compared to the observations. Upslope flows play an important role in the presence of this early (pre-noon) minimum while the timing and magnitude of the minimum depend only weakly on the temperature structure. An increase in large-scale flow has a noticeable impact on the diurnal variability with a more gradual decrease in daytime CO2 concentration, similar to summer-averaged observations. From the idealized simulations and a case study, it is concluded that multi-scale flows and their interactions have a large influence on the observed diurnal variability.
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Qute : Shapiro, A. ,Axelsen, S. L. ,Axelsen, S. L. ,Steeneveld, G. J. ,Martínez, D. ,De Wekker, S. F. J. ,De Wekker, S. F. J. , A preliminary investigation of boundary layer effects on daytime atmospheric CO2 concentrations at a mountaintop location in the Rocky Mountains. Acta Geophysica Vol. 57, no. 4/2009