Arctic sea surface CO2 partial pressure based on LiDAR
The spaceborne light detection and ranging(LiDAR),as a novel active remote sensing technology,offers possibilities for global diurnal research.In this study,global sea surface chlorophyll-a(Chla)concentrations were in-verted using satellite data from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations(CALIPSO).A feed-forward neural network model based on LiDAR data(FNN-LID)was developed to reconstruct a long-term diurnal datas-et of sea surface p CO2 in the Arctic Ocean.Subsequently,verification and analysis were conducted on the polar sea sur-face Chla concentrations and sea surface p CO2 based on active remote sensing.The results demonstrated that the inver-sion products generated by this algorithm exhibit high data quality and exhibit favorable consistency with both other pas-sive remote sensing products and buoy observations.Moreover,these products effectively fill data gaps during polar winters.Along the Arctic Ocean,margin seas significantly influenced by terrestrial sources consistently display high sea surface Chla concentrations.The spatial distribution of sea surface p CO2 in the Arctic Ocean manifests meridional varia-tions,with marked seasonal fluctuations,even higher than 80 μatm.Over the past two decades,the Arctic Ocean has consistently acted as a carbon dioxide sink,while areas with substantial sea ice decline such as the East Siberian Sea and Kara Sea exhibit pronounced increases in sea surface p CO2.
spaceborne LiDARarctic oceansea surface CO2 partial pressurepolar nightlong-term variation