Evaluation of drop in official air temperature record at Okayama caused by relocation of observation field of Okayama Local Meteorological Observatory - By comparison with records observed at surrounding points -

Abstract

Statistical change in official temperature records at Okayama City caused by relocation of meteorological observation field of Meteorological Agency was evaluated. The observation field of Okayama local meteorological observatory was moved to the Tsushima Campus of Okayama University from the downtown area of Okayama City in March, 2015. Comparison between the air temperature records measured at meteorological agency station and the records at Tanjo Pond in Tsushima Campus, showed 0.56 ℃ drop in annual average before and after relocation. Moreover, comparison between the records of Okayama local meteorological observatory and that at the surrounding meteorological observing 9 stations showed 0.55 ℃ drop in annual average. Those results suggest that the relocation dropped annual average of air temperature by about 0.6 ℃