In this work, we analysed the Cheongyang geomagnetic baseline data from 2014 to 2016. We observed a step of more than 5 nT in H
baseline on 2014 and 2015 due to artificial magnetic noise in the absolute hut. In addition, the baseline shows a yearly drift of more than 10 nT due to temperature variations in the fluxgate magnetometer hut. The quality of the baselines was improved by correcting the discontinuity in the H
baselines and performing the temperature effect correction.