Distribution Characteristics Of Lower Troposphere Atmospheric Co2 In Hefei Science Island

Based on the carbon dioxide mass mixing ratio concentration profiles of Hefei Science Island from 2013 to 2016, the distribution characteristics of carbon dioxide in the subtropical monsoon climate and the characteristics of carbon dioxide source and sink in Hefei Science Island were analyzed from the night, season and year respectively. At lower altitudes, CO2 builds up during nighttime hours as respiration is trapped within the nocturnal boundary layer. Throughout this nighttime the CO2 concentration at 390m shows that only little variation. After sunrise, convection begins to spread the CO2 trapped at low levels to higher altitudes. When the measurement height was more than 100m, the obvious seasonal change was shown, with the minimum in summer and the maximum in winter, which the difference in concentration of about 19.32mg/m(3). The annual distribution of the concentration of carbon dioxide from 2013 to 2016 had no significant difference in the gradient change of the height above 100m, the correlation coefficient was above 0.9, and the CO2 vertical concentration goes up with a rate of about 4.35mg/m(3) per year. Through data analysis from three different timescales, it could be concluded that the concentration of carbon dioxide near the ground was greatly influenced by the atmospheric environment. The seasonal distribution of carbon dioxide concentration was the result of a combination of atmospheric movement and the activities of plants and animals In the process of long-term carbon dioxide cycling, there was a current that the near-surface carbon dioxide transported to a higher altitude.