Climatology and temporal evolution of the atmospheric semidiurnal tide in present‐day reanalyses

• Published in: Journal of geophysical research. Atmospheres 2016-05, Vol.121 (9), p.4614-4626
• Main Authors: Díaz‐Argandoña, J., Ezcurra, A., Sáenz, J., Ibarra‐Berastegi, G., Errasti, I.
• Format: Article
• Language: English
• Subjects: Atmospheric chemistry; Atmospheric evolution; Atmospheric research; atmospheric tide; Atmospheric tides; Atmospherics; Climate; Climate science; Climate system; Climatology; Current data; Datasets; Diurnal variations; Empirical analysis; Evolution; Frozen products; Geographical distribution; Geophysics; Heat transfer; Interpolation; Latent heat; Latent heat release; Latitude; Mathematical analysis; Mathematical models; Meteorology; Precipitation; Precipitation measurements; Rain; Rainfall; reanalyses; Seasonal variability; Seasonal variation; Seasonal variations; Semidiurnal tides; Temporal variations; Tides; Tropical climate; Tropical rainfall; Tropical Rainfall Measuring Mission (TRMM)
• ISSN: 2169-897X; 2169-8996
• DOI: 10.1002/2015JD024513

The solar semidiurnal atmospheric tide (S2) was extracted from seven reanalysis data sets, including current data sets, such as CFSR (Climate Forecast System Reanalysis), MERRA (Modern‐Era Retrospective Analysis for Research and Applications), ERA‐Interim (ECMWF Reanalysis), and 20CR (Twentieth Century Reanalysis), and older frozen products, such as NCEP/NCAR (National Center for Environmental Prediction/National Center for Atmospheric Research), ERA‐40 (ECMWF Reanalysis), and JRA‐25 (Japanese 25 year Reanalysis). In this calculation, we emphasized the temporal variation of the tide. We also calculated the tidal error, which was sizable at high latitudes and over short averaging periods and large for 20CR at all latitudes. Because of the four standard daily samples, the interpolation scheme of van den Dool et al. (1997) was used when necessary. We found this method to be accurate for zonally averaged tides only. Comparing the climatology from the MERRA and CFSR S2 with a recent empirical tide model showed that MERRA better represented the geographical structure of the tide, especially its phase. We found a bias in the phase in all of the reanalysis data sets except for MERRA. The temporal evolution of the tide was inconsistent between the different data sets, although similar seasonal variations were observed. The seasonal cycle was also better depicted in MERRA. The S2 calculated from MERRA and satellite precipitation measurements from TRMM (Tropical Rainfall Measuring Mission) presented results that were inconsistent with the hypothesis in which rainfall latent heat release represents S2 forcing and functions as a source of S2 seasonal variability. Key Points MERRA performs best in reproducing the climatology of S2 at ground level Different reanalysis data sets are not consistent with the temporal variability of the tide The S2 connection to latent heating was assessed using TRMM data