Implementation of Improved Parameterization of Terrestrial Flux in WRF‐VPRM Improves the Simulation of Nighttime CO₂ Peaks and a Daytime CO₂ Band Ahead of a Cold Front

Abstract

An enhanced CO 2 mole fraction band was often observed immediately ahead of cold fronts during the Atmospheric Carbon and Transport (ACT)-America mission (Pal et al., 2020). Correct simulation of the gradients of CO 2 across cold fronts and understanding of the formation mechanisms are needed for accurate estimation of regional CO 2 budget (

Analysis of CO<sub>2</sub> spatio-temporal variations in China using a weather–biosphere online coupled model

“…In recent years, tremendous efforts have been made in China to control anthropogenic emissions from fossil fuel combustion for both air quality and climate mitigation purposes (Zheng et al, 2018). While the sources and sinks of air pollutants have been thoroughly examined and well documented (Huang et al, 2020), the dynamics of CO 2 at regional to national scales remains poorly understood due to a lack of longterm observations and limited modelling studies (Han et al, 2020). Li et al (2020) applied a weather-biosphere model with tower observations to analyse CO 2 fluxes and concentrations over mixed forest and rice paddy areas in northeast China, but the 1-year simulation limits the attempt to investigate interannual CO 2 variation, which is subject to substantial change (Z. .…”

Atmospheric Carbon and Transport – America (ACT-America) Datasets: Description, Management, and Delivery

“…An elevated CO 2 band (416 ppm) was found at the frontal boundary, similar to results from the summer-2016 campaign (Figure 3a). This phenomenon appears closely tied to biological CO 2 fluxes (Samaddar et al, 2021), perhaps particularly respiratory fluxes (Hu et al, 2021). CO and CH 4 mole fractions were higher in the cold sector than in the warm sector (Figures 3d and 3e), likely indicative of large CH 4 emissions from animal agriculture in the upper Midwest and perhaps larger upwind anthropogenic CO sources in the upper Midwest (analyses in preparation).…”

“…Gaudet et al (2020), for example, evaluated the skill of 10 global CO 2 inversion models from the OCO-2 MIP using 148 airborne vertical profiles of CO 2 for frontal cases from the ACT-America Summer 2016 campaign. High-resolution models (Hu et al, 2021;Samaddar et al, 2021) of the elevated CO 2 band observed along the frontal boundary shown in Pal et al (2020a) have been evaluated using the ACT-America airborne data, as has a newly developed global CO 2 transport model (Zheng et al, 2020). As noted previously, OCO-2 XCO 2 variability at local to synoptic scales has been evaluated using ACT-America lidar and in situ observations (Bell et al, 2020).…”

Atmospheric Carbon and Transport – America (ACT‐America) Data Sets: Description, Management, and Delivery

“…An elevated CO2 band (416 ppm) was found at the frontal boundary, similar to results from the summer-2016 campaign (Figure 3a). This phenomena appears closely tied to biological CO2 fluxes (Samaddar et al, 2021), perhaps particularly respiratory fluxes (Hu et al, 2021). CO and CH4 mole fractions were higher in the cold sector than in the warm sector (Figure 3d and 3e), likely indicative of large CH4 emissions from animal agriculture in the upper Midwest and perhaps larger upwind anthropogenic CO sources in the upper Midwest (analyses in preparation).…”

“…Gaudet et al (2020), for example, evaluated the skill of ten global CO2 inversion models from the OCO-2 MIP using 148 airborne vertical profiles of CO2 for frontal cases from the ACT-America Summer 2016 campaign. High resolution models (Samaddar et al, 2021;Hu et al, 2021) of the elevated CO2 band observed along the frontal boundary shown in Pal et al (2020a) have been evaluated using ACT-America airborne data, as has a newly developed global CO2 transport model (Zheng et al, 2020). As noted previously, OCO-2 XCO2 variability at local to synoptic scales has been evaluated using ACT-America lidar and in situ observations (Bell et al, 2020).…”