10025 american dating site
Over the Central Plains, precipitation responses during the spring and summer seasons (the main seasons of moisture supply) are less consistent across models, and the drying is driven primarily by the increased evaporative demand.
For example, whereas the PDSI trends are drier than the soil moisture condition over the Southwest in the ACCESS1-0 model, PDSI is actually less dry than the soil moisture in the MIROC-ESM and Nor ESM1-M simulations over the same region (fig. These outlier observations, showing no consistent bias, in conjunction with the fact that the overall comparison between PDSI and modeled soil moisture is markedly consistent, provide mutually consistent support for the characterization of surface moisture balance by these metrics in the model projections. 3) are drier during the Medieval megadrought interval (1100–1300 CE) than either the Little Ice Age (1501–1849) or historical periods (1850–2005).
We also conduct the same analyses for a more moderate emissions scenario (RCP 4.5).
Over the calibration interval (1931–1990), the PDSI distributions from the models are statistically indistinguishable from the North American Drought Atlas (NADA) (two-sided Kolmogorov-Smirnov test, ≥ 0.05), although there are some significant deviations in some models during other historical intervals.
In both regions, the model-derived PDSI closely tracks the two soil moisture metrics (figs.
S6 and S7), correlating significantly for most models and model intervals (figs. Over the historical simulation, average model correlations (Pearson’s r) between PDSI and SM-30cm are 0.86 and 0.85 for the Central Plains and Southwest, respectively.