Saharan Air Layer Intrusions to the Caribbean and CONUS

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Saharan Air Layer Intrusions to the Caribbean and CONUS Edward Hyer Arunas Kuciauskas Naval Research Laboratory BoAom Line Up Front • Saharan Air Layer is responsible for dry and dry +dusty air intrusion over the tropical AtlanGc and periodic episodes westward to Texas/Mexico • Interest in these occurrences is widespread; they have important AQ implicaons as well as severe weather, meteorology, and remote sensing (e.g. SST, satellite radiances) • NRL has developed several tools including advanced processing of remotely sensed data as well as model products for analysis of these events Dry Air (Blue) Propagates off the Sahara– someGmes (not always) dusty air Total Precipitable Water Anomaly from DMSP AERONET Sun Photometer AOD from University of Puerto Rico at La Parguera InternaGonal ConsorGum for Aerosol PredicGon MulG-Model Ensemble (ICAP-MME) Dust AOD forecast inialized 6/22/2014 00Z IniGal: Crossing over NW Africa coast 20140622 10:30 LST AOD > 0.8 (dust) Two days later Four days later – approaching Puerto Rico Two days later - 20140624 20140624 10:30 LST 20140626 10:30 Four days later – approaching Puerto Rico LST 20140626 *Puerto Rico *Puerto Rico Aqua MODIS AOD (CollecGon 5, Dark Target Algorithm) (over water only) Matching the Gmes of the ICAP-MMD IniGal: Crossing over NW Africa coast 20140622 10:30 LST Two days later Four days later – approaching Puerto Rico 20140624 10:30 LST 20140626 10:30 LST NPP VIIRS processed with the “Blue Light” dust enhancement algorithm Gives a clear visual of dust influence– not quanGtaGve Research QuesGons & Tools Research QuesGons Tools • How accurately can models • MulG-model ensembles forecast the beginning Gme, • Meteorological ensembles duraon, and intensity of Saharan dust intrusions at a US • In situ and space-based lidar locaon? verGcal profiles • How o[en do dust intrusions • Satellite dust enhancement transported across the AtlanGc products affect surface air in US? • Surface observaons • Can models capture the mixing down of dust into surface layers? .

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