NOAA PSL Climate Data Repository - Paper Figures

Figure 1. The observed 2011 June-August (JJA) averaged surface temperature departures (°C, top), the time series of JJA Texas surface temperature departures (°C, bottom, left), and the probability distribution functions of the JJA Texas surface temperatures for two sub-periods of the historical record: 1895-1954 (blue curve), and 1955-2010 (red curve). The observed 2011 JJA Texas surface temperature shown in gray tick mark. Data source is the NCDC U.S. Climate Divisions, and departures are relative to 1981-2010 means. The PDFs are non-parametric curves constructed using the R software program which utilizes a kernal density estimation and a Guassian smoother.

Figure 4. Observed SST anomalies (°C, left) and U.S. precipitation anomalies (% of climatology, right). Top panels show contemporaneous conditions for June-August 2011, and bottom panels show antecedent conditions for October 2010-May 2011. All anomalies are relative to an observed 1981-2010 climatology.

Figure 7. Probability distribution functions of the AMIP (top) and CMIP5 (bottom) simulated summer Texas precipitation anomalies (% of climatology, left) and surface temperature (°C, right). Each panel plots two curves, one for the frequency distribution of simulations during 1981-2010, and the other for the frequency distribution of simulations during 2011. For CMIP5, 600 (220) individual simulations are used for 1981-2010 (2011). For AMIP, 360 (80) individual simulations are used for 1981-2010 (2011). The verical gray tic marks denote the observed 2011 anomalies. All departures are relative to a 1981-2010 reference. The PDFs are non-parametric curves constructed using the R software program which utilizes a kernal density estimation and a Guassian smoother.

Figure 10. The simulated relationship between June-August Texas averaged rainfall departures (% of climatology) and surface temperature departures (°C) for wet (dry) Texas antecedent October-May conditions in green (red) dots. The data is based on the 12-member suite of 1950-2010 GFS AMIP simulations, and the plotted values are for the 10% wettest (driest) October-May realizations corresponding to 72 samples for each extreme.

Figure 13. NOAA/NCEP operational dynamical predictions of June-August seasonally averaged precipitation anomalies (% of climatology, left) and surface temperature anomalies (°C, right). Probability distribution functions as in Fig. 7. Spatial anomaly maps as in Fig. 6, except based on the ensemble mean of the CFS forecasts. For CFSv1, 435 (124) individual hindcasts (forecasts) are used for 1981-2009 (2011). For CFSv2, 696 (124) individual hindcasts (forecasts) are used for 1982-2010 (2011All hindcasts and forecasts are based on initializations from May analyses, and anomalies are calculated relative to the period of available hindcast climatologies for all May initializations.

Figure 2. Histogram of the temperature departures (°C) for the hottest Texas summers occurring in consecutive, non-overlapping 100 year samples of CMIP5 pre-industrial simulations. The block maxima analysis is based on 18 different CMIP5 models, most of which have at least 500-yr long simulations. The prior record observed summertime Texas departure during 1895-2010 indicated by short green tick mark, and the 2011 new record summer departure indicated by long green tick mark. The red PDF is the Gaussian fitted curve to the histogram, while the blue PDF is the non-parametric curve constructed using the R software program which utilizes a kernal density estimation and a Guassian smoother.

Figure 5. The historical relationship between June-August Texas averaged rainfall departures (% of climatology) and surface temperature departures (°C). Each dot corresponds to a summer during 1895-2010, and the 2011 value is indicated by the blue wagon wheel. Inset values are for the correlation (R) and the slope of the linear fit expressed as °C/%Pcpn departure.

Figure 8. The AMIP (top) and CMIP5 (bottom) simulated relationship between June-August Texas averaged rainfall departures (% of climatology) and surface temperature departures (°C). Left (right) panels show the relationship for 1981-2010 (2011). Each dot corresponds to the temperature/precipitation for a particular model realization. For AMIP, there are 360 (80) realizations for 1981-2010 (2011). For CMIP, there are 720 (220) realizations for 1981-2010 (2011). Inset values are for the correlation (R) and the slope (b) of the linear fit expressed as °C/%Pcpn departure. The blue wagon wheel denotes the observed JJA 2011 values.

Figure 11. Probability distribution functions (PDFs) of GFS simulated June-August Texas surface temperature based on a joint condition of dry antecedent and dry summer conditions (red curve), and for unconditional model realizations (blue curve). Red PDF is comprised of the 41 realizations that were among both the driest 20% Oct-May and the driest 20% June-August conditions. Blue PDF is the unconditioned frequency distribution that is comprised of all 720 model realizations. Grey tic mark denotes the magnitude of the observed JJA 2011 Texas temperature departure.

Figure 3. The 15-case composite SST (°C, left) and U.S. precipitation anomalies (% of climatology, right) based on the 1 in 100 year hottest summertime Texas heat wave events occurring in a 1500-yr simulation of CCSM4. The experiment is an unforced, pre-industrial simulation. Top panels show contemporaneous conditions for June-August, and bottom panels show antecedent conditions for October-May. All anomalies are relative to the CCSM4 climatology.

Figure 6. The June-August 2011 U.S. precipitation anomalies (% of climatology, left) and surface temperature anomalies (°C, right). Observed (top), ensemble mean AMIP simulated (middle), and ensemble mean CMIP5 simulated (bottom). The AMIP results are based on an 80-member GFS average for 2011, and the CMIP results are based on a 220-member average using 20 different models for a 11-year window of JJA conditions centered on 2011. All anomalies are relative to the respective data set’s 1981-2010 climatology, and the observed scale of plotted anomalies is double that shown for the simulations. The reference AMIP simulation uses the same GHG concentrations as those specified in the 2011 experiments.

Figure 9. Observed (red curve) and AMIP ensemble mean (thick black curve) cumulative Texas precipitation departures (mm) from October 20110 through August 2011. Thin black curves are for each of the 80 members of the GFS AMIP simulations. Orange curves are the cumulative precipitation departures for the subset of 8 warmest Texas JJA 2011 GFS realization. Departures are computed relative to the respective data sets’ 1981-2010 mean.

Figure 12. Observed (green dot) and simulated (box/whiskers) trends in June-August Texas surface temperature (°C/decade). Trends are computed for different beginning years from 1901 (left most box) to 1981 (right most boxes), staggered at 10-year increments, while the end year for all trend calculations is 2010 Thus, the longest trend period is for a 110-yr period (left side), and the shortest is for a 30-yr period (right side). Dark (light) box/whiskers display the CMIP5 (AMIP) simulation trends based on a 20-member (12-member) ensemble. The extreme values of the model simulated trends are shown by the red and blue asterikes.