A Vertical Diffusion Scheme to estimate the atmospheric rectifier effect

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

8

Atmospheric Composition And Structure: Biosphere/Atmosphere Interactions, Atmospheric Composition And Structure: Planetary Atmospheres (5405, 5407, 5409, 5704, 5705, 5707), Global Change: Biogeochemical Processes (4805), Geochemistry: Planetary Geochemistry (5405, 5410, 5704, 5709, 6005, 6008)

Scientific paper

The magnitude and spatial distribution of the carbon sink in the extratropical Northern Hemisphere remain uncertain in spite of much progress made in recent decades. Vertical CO2 diffusion in the planetary boundary layer (PBL) is an integral part of atmospheric CO2 transport and is important in understanding the global CO2 distribution pattern, in particular, the rectifier effect on the distribution [Keeling et al., 1989; Denning et al., 1995]. Attempts to constrain carbon fluxes using surface measurements and inversion models are limited by large uncertainties in this effect governed by different processes. In this study, we developed a Vertical Diffusion Scheme (VDS) to investigate the vertical CO2 transport in the PBL and to evaluate CO2 vertical rectification. The VDS was driven by the net ecosystem carbon flux and the surface sensible heat flux, simulated using the Boreal Ecosystem Productivity Simulator (BEPS) and a land surface scheme. The VDS model was validated against half-hourly CO2 concentration measurements at 20 m and 40 m heights above a boreal forest, at Fraserdale (49°52'29.9''N, 81°34'12.3''W), Ontario, Canada. The amplitude and phase of the diurnal/seasonal cycles of simulated CO2 concentration during the growing season agreed closely with the measurements (linear correlation coefficient (R) equals 0.81). Simulated vertical and temporal distribution patterns of CO2 concentration were comparable to those measured at the North Carolina tower. The rectifier effect, in terms of an annual-mean vertical gradient of CO2 concentration in the atmosphere that decreases from the surface to the top of PBL, was found at Fraserdale to be about 3.56 ppmv. Positive covariance between the seasonal cycles of plant growth and PBL vertical diffusion was responsible for about 75% of the effect, and the rest was caused by covariance between their diurnal cycles. The rectifier effect exhibited strong seasonal variations, and the contribution from the diurnal cycle was mostly confined to the surface layer (less than 300 m).

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A Vertical Diffusion Scheme to estimate the atmospheric rectifier effect does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Vertical Diffusion Scheme to estimate the atmospheric rectifier effect, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Vertical Diffusion Scheme to estimate the atmospheric rectifier effect will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1020879

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.