English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Abstract. Accurate monitoring of atmospheric carbon dioxide(CO2) and its distribution is of great significance for studying thecarbon cycle and predicting future climate change. Compared to theground observational sites, the airborne observations cover a wider areaand simultaneously observe a variety of surface types, which helps witheffectively monitoring the distribution of CO2 sources and sinks. Inthis work, an airborne experiment was carried out in March 2019 over theShanhaiguan area, China (39–41∘ N, 119–121∘ E). An integrated path differentialabsorption (IPDA) light detection and ranging (lidar) system and acommercial instrument, the ultraportable greenhouse gas analyser (UGGA),were installed on an aircraft to observe the CO2 distribution overvarious surface types. The pulse integration method (PIM) algorithm was usedto calculate the differential absorption optical depth (DAOD) from the lidardata. The CO2 column-averaged dry-air mixing ratio (XCO2) wascalculated over different types of surfaces including mountain, ocean, andurban areas. The concentrations of the XCO2 calculated from lidarmeasurements over ocean, mountain, and urban areas were 421.11 ± 1.24, 427.67 ± 0.58, and 432.04 ± 0.74 ppm, respectively.Moreover, through the detailed analysis of the data obtained from the UGGA,the influence of pollution levels on the CO2 concentration was alsostudied. During the whole flight campaign, 18 March was the most heavily pollutedday with an Air Quality Index (AQI) of 175 and PM2.5 of 131 µg m−3. The aerosol optical depth (AOD) reported by a sun photometerinstalled at the Funing ground station was 1.28. Compared to the otherdays, the CO2 concentration measured by UGGA at different heights wasthe largest on 18 March with an average value of 422.59 ± 6.39 ppm,which was about 10 ppm higher than the measurements recorded on 16 March.Moreover, the vertical profiles of Orbiting Carbon Observatory-2 (OCO-2) andCarbonTracker were also compared with the aircraft measurements. All thedatasets showed a similar variation with some differences in their CO2concentrations, which showing a good agreement among them.

Atmospheric carbon dioxide measurement from aircraft and comparison with OCO-2 and CarbonTracker model data