Analysis of spatial distribution in tropospheric and sea surface temperature trends

Abstract

Regional patterns in tropospheric and sea surface temperature (SST) trends are examined for the period 1979 ??01 using MSU, NCEP-NCAR, ECMWF ERA-40 reanalyses, NOAA OI SST, and the CARDS radiosonde data set. Trends are estimated using a nonparametric Mann-Kendall approach. Substantial regional variability in temperature trends is seen in all of these data sets, with the magnitude of the variability (including substantial regions with cooling trends) far exceeding the average warming trend. The global analyses from MSU and the NCAR/NCEP and ECMWF reanalyses are used to identify sampling problems in using the radiosonde network to infer global trends. Analysis of the trends in tropospheric temperature concurrent with trends in SST shows regions where the signs disagree for both surface cooling and warming. Interpretation of these differing trends using the reanalyses suggest that the models used for the reanalyses are simulating the necessary dynamics/thermodynamics thatcould lead to a tropospheric cooling in contrast to a surface warming (and vice versa).