BUSCADOR RECOLECTA

In this study, global reanalysis dataset fields of meteorological parameters (temperature and geopotential height at different atmospheric levels) in the period 1948???2020, were used to characterize the main dynamic and thermodynamic features of African dust outbreaks (ADO) produced over regions of the Iberian Peninsula and the Balearic Islands. The record of ADO previously identified with a tried-and-true procedure in 8 different areas of this domain in the period 2001???2020 and the data sets of dust load contributions estimated for all ADO days in each region, were used to check our results. Thus, we demonstrated that air masses of African origin produced a significant increase in the levels of certain thermodynamic variables (geopotential thickness in the 1000???500 hPa layer (GT), mean potential temperature between 925 and 700 hPa (TPOT), and temperature anomalies at 850 hPa (TANOM)) over the regions of study, especially when particular synoptic-scale atmospheric circulation types (CT) occurred. Moreover, higher levels of the three thermodynamic parameters resulted in events with higher contributions of dust load to the regional background levels of PM10 in all regions. Finally, we obtained a statistically significant upward trend for days under ADO CT and their associated daily mean values of GT, TPOT and TANOM from 1948 to 2020. These results point to an increase in the frequency of air mass transport from North Africa to the western Mediterranean basin and on the intensity of the ADO produced as a consequence of this transport, over 1948???2020.

In this study, global reanalysis dataset fields of meteorological parameters (temperature and geopotential height at different atmospheric levels) in the period 1948–2020, were used to characterize the main dynamic and thermodynamic features of African dust outbreaks (ADO) produced over regions of the Iberian Peninsula and the Balearic Islands. The record of ADO previously identified with a tried-and-true procedure in 8 different areas of this domain in the period 2001–2020 and the data sets of dust load contributions estimated for all ADO days in each region, were used to check our results. Thus, we demonstrated that air masses of African origin produced a significant increase in the levels of certain thermodynamic variables (geopotential thickness in the 1000–500 hPa layer (GT), mean potential temperature between 925 and 700 hPa (TPOT), and temperature anomalies at 850 hPa (TANOM)) over the regions of study, especially when particular synoptic-scale atmospheric circulation types (CT) occurred. Moreover, higher levels of the three thermodynamic parameters resulted in events with higher contributions of dust load to the regional background levels of PM10 in all regions. Finally, we obtained a statistically significant upward trend for days under ADO CT and their associated daily mean values of GT, TPOT and TANOM from 1948 to 2020. These results point to an increase in the frequency of air mass transport from North Africa to the western Mediterranean basin and on the intensity of the ADO produced as a consequence of this transport, over 1948–2020., This study was funded by research projects POSAHPI (Agencia Estatal de Investigación, PID2019–108101RB-I00) and ASAH-AS (Grants for scientific research projects in the National Parks Network for the year 2021, Spanish Ministry for the Ecological Transition and the Demographic Challenge, ref. 2799/2021). The authors also acknowledge the NOAA/OAR/ESRL PSD, Boulder, CO, USA for providing access to the reanalysis global meteorological fields, the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT trajectory model, the Atmospheric Modelling & Weather Forecasting Group - University of Athens, the Earth Science Department - Barcelona Supercomputing Centre, the Naval Research Laboratory and the NASA for the provision of the SKIRON, DREAM/BSCDREAM8b, NAAPs aerosol maps and the satellite imagery, respectively., Peer reviewed