Figure 28:   Tropical (30° S to 30° N Latitude) temperature trends (deg. K/decade) for the period 1978-2002 as derived by Tett and Thorne (2004) using the Fu et al. (2004) method and data from radiosonde, reanalysis, and model run products. For the non-satellite data sets, static weighting functions were used to estimate MSU2 and MSU4 equivalents. Tfjws is the free troposphere trend they derived for each data set using the Fu et al. published coefficients applied to the T2 and T4 data. All datasets were zonally averaged, then cosine-weighted and least-square estimates of the linear trends were computed from annual-means. Indian data were removed from the HadRT2.1s analysis. Also shown are the logarithms of the pressure-weighted 850–300 hPa temperatures and the pressure-weighted 1,000–100-hPa temperatures. The RMS of the annual-mean differences between those trends and Tfjws is shown in brackets. Surface trends are from data averaged over land and ocean. For ERA-40, 2-meter temperatures were used over land and sea surface temperatures over the oceans. Surface temperatures from HadCRUT2v were used for RSS, UAH and HadRT2.1s. For the two model ensembles, the average, largest and smallest trends are shown. The difference between largest and smallest gives an indication of uncertainty in the ensemble average. The coupled (HadCM3) and atmosphere-only (HadAM3) simulations differ in their forcings, with the main differences being a correction of an error in ozone loss and changes to the sulphur cycle in the HadAM3 simulations. The HadAM3 (HadCM3) ensemble consists of six (four) simulations. Taken from Tett and Thorne (2004).

Figure 29:   The free troposphere weighting function of Fu and Johanson (2004) for the tropics (30 deg. S to 30 deg. N Latitude) compared to the corresponding weightings for MSU2 and 2LT/TLT. Taken from Fu and Johanson (2004).

Figure 30:   Modeled and observed vertical trend profiles for the tropics (30 deg. S to 30 deg. N Latitude) as reported by Douglass et al. (2004b). HadCM3 trends are for 1975-1995, DOE PCM trends are for 1979-1999, and GISS SI2000 trends are for 1979-1998. The MSU trend (single point) gives TLT data from UAH Version D (Christy et al., 2000) truncated to 1996. The surface trend (single point) is from Jones et al. (1999). The NNR profile is for the NCEP/NCAR 2-Meter Reanalysis (Kisteler et al., 2001). MSU, surface, and NNR trends are for the period 1979-1996. Taken from Douglass et al. (2004b).

Figure 31:   Simulated trends in global-mean free-tropospheric temperature as derived by Gillett et al. (2004) using the Fu et al. method applied to 1958-1999 results from the DOE PCM coupled AOGCM. Black crosses, are 850-300 hPa layer trends in each of four realizations of an experiment with anthropogenic and natural forcing. Asterisks indicate free-tropospheric temperature trends reconstructed from synthetic MSU2 and MSU4 trends using the method of Fu et al. These are calculated using three different sets of regression coefficients, which are derived from radiosonde observations by Fu et al. (pink asterisks), estimated from the PCM experiments (dark blue asterisks), and obtained directly from the MSU2 and MSU4 weighting functions (light blue asterisks). Red crosses, simulated trends in MSU2; green crosses, simulated trends in TLT. The simulated trend in MSU4 is -0.36 +/- 0.03 deg. K per decade. The model’s surface warming over 1890–1999 (0.62 °C) is consistent with that observed. Taken from Gillett et al. (2004).

Figure 32:   Global mean annual mean temperature trends from GISS SI2000 for (top) 1958–98 and (bottom) 1979–98 based on linear trends. Model results are for oceans A, B, and E with (a) five forcings and (b) six forcings. Radiosonde data are from HadRT2.0 and HadRT2.1 (Parker et al., 1997). The surface observations (green triangles) are the land–ocean data of Hansen et al. (1999) with SST of Reynolds and Smith (1994) for ocean areas. The green bars are MSU trends for Channels 2LT, MSU2, and MSU4 from UAH Ver. D (Christy et al. 2000). Error bars reflect 2-sigma confidence intervals adjusted for autocorrelation (Santer et al. 2000b). Taken from Sun and Hansen (2003).

Figure 33:   Transient responses of MSU 2LT, MSU2, and MSU4 layer temperatures, and global oceanic heat content anomalies in GISS SI2000 using the Oceans A, B, and E component models. Observed MSU layer temperatures are from UAH Ver. D (Christy et al., 2000). Results on the right employ six forcings, while those on the left exclude tropospheric aerosol changes. Taken from Sun and Hansen (2003).