Projected changes in atmospheric moisture transport contributions associated with climate warming in the North Atlantic.

Global warming and associated changes in atmospheric circulation patterns are expected to alter the hydrological cycle, including the intensity and position of moisture sources. This study presents predicted changes for the middle and end of the 21st century under the SSP5-8.5 scenario for two important extratropical moisture sources: the North Atlantic Ocean (NATL) and Mediterranean Sea (MED). Changes over the Iberian Peninsula-considered as a strategic moisture sink for its location-are also studied in detail. By the end of the century, moisture from the NATL will increase precipitation over eastern North America in winter and autumn and on the British Isles in winter. Moisture from the MED will increase precipitation over the southern and western portions of the Mediterranean continental area. Precipitation associated with the MED moisture source will decrease mainly over eastern Europe, while that associated with the NATL will decrease over western Europe and Africa. Precipitation recycling on the Iberian Peninsula will increase in all seasons except summer for mid-century. Climate change, as simulated by CESM2 thus modifies atmospheric moisture transport, affecting regional hydrological cycles.

Uncertainty in surface wind speed projections over the Iberian Peninsula: CMIP6 GCMs versus a WRF-RCM.

This study assessed the projected near-surface wind speed (SWS) changes and variability over the Iberian Peninsula for the 21st century. Here, we compared Coupled Model Intercomparison Project Phase 6 global climate models (GCMs) with a higher spatial resolution regional climate model (RCM; ∼20 km), known as WRF-CESM2, which was created by a dynamic downscaling of the Community Earth System Model version 2 (CESM2) using the Weather Research and Forecasting (WRF) model. Our analysis found that the GCMs tended to overestimate observed SWS for 1985-2014, while the higher spatial resolution of the WRF-CESM2 did not improve the accuracy and underestimated the SWS magnitude. GCMs project a decline of SWS under high shared socioeconomic pathways (SSPs) greenhouse concentrations, such as SSP370 and SSP585, while an interdecadal oscillation appears in SSP126 and SSP245 for the end of the century. The WRF-CESM2 under SSP585 predicts the opposite increasing SWS. Our results suggest that 21st-century projections of SWS are uncertain even for regionalized products and should be taken with caution.

Dataset of outer tropical cyclone size from a radial wind profile.

Pérez-Alarcón et al. [1] developed a comparative climatology of the outer radius of tropical cyclones (TCs) from several radial wind profiles. They showed that the Willoughby et al. (2006) (W06) profile can be used to reproduce the TC tangential wind speed; thus, this profile is skilful for estimating the TC outer radius. Here, we present a database of TC sizes estimated from the W06 radial wind profile in each cyclogenetic basin worldwide. The database incorporates the critical wind radii, where the tangential wind speed is approximately 17.5 ms-1 (R34), 26 ms-1 (R50), 33 ms-1 (R64), and 51 ms-1 (R100), estimated by the W06 profile. The database has a comma-delimited text format with six-hour information on the location, maximum wind speed, central pressure, and the different TC metrics mentioned above. This database has a similar structure to that of the Atlantic Hurricane Database (HURDAT2) of the National Hurricane Center. The database presented here is applicable to studies on TC storm surge risks as well as to the determination of the sources and sinks of atmospheric moisture related to tropical cyclogenesis processes.