CO2 over a coastal urban location and its forcing

Recognizing the role of Carbon dioxide (CO 2 ) in altering climate research and air pollution, direct measurements carried out over a coastal urban station using Li-COR CO 2 /H 2 O analyser. The objective of the present study is to examine CO 2 variability during December-March. Day-to-day variability of CO 2 ranges from 380-550 ppm with a mean (423.1) and standard deviation (29.2). Monthly mean diurnal variability of CO 2 is maximum during midnight to early morning hours and minimum during afternoon. Overall diurnal variation is similar during the entire months. The link between CO 2 concentrations with Wind speed (WS), Atmospheric temperature (T) is examined. Wind speed varies inversely with CO 2 . Atmospheric temperature shows an exponentially decaying relation with CO 2 . The diurnal CO 2 variability is associated with the competing source/sink mechanisms. The CO 2 forcing is estimated and varies from 0.75 to 3.5 Wm -2 with temperature change from 0.75 to 2.0 0 C.