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David Painemal Duarte

Publications and source records attributed to David Painemal Duarte.

Impact of Meteorological Factors on the Mesoscale Morphology of Cloud Streets during a Cold-Air Outbreak over the Western North Atlantic

Postfrontal clouds (PFC) are ubiquitous in the marine boundary layer, and their morphology is essential to estimating the radiation budget in weather and climate models. Here we examine the roles of sea surface temperature (SST) and meteorological factors in controlling the mesoscale morphology and evolution of shallow clouds associated with a cold-air outbreak that occurred on 1 March 2020 during phase I of the Aerosol Cloud Meteorology Interactions over the Western Atlantic Experiment (ACTIVATE). Our results show that the simulated PFC structure and ambient conditions by the Weather Research and Forecasting (WRF) Model are generally consistent with observations from GOES-16 and dropsonde measurements. We also examine the thermodynamical and dynamical influences in the cloud mesoscale morphology using WRF sensitivity experiments driven by two meteorological forcing datasets with different domain-mean SST and spatial gradients, which lead to dissimilar values of hydrometeor water path and cloud core fraction. The SST from ERA5 leads to weaker stability and higher inversion height than the SST from FNL does. In addition, the use of large-scale meteorological forcings from ERA5 yields a distinctive time evolution of wind direction shear in the inner domain, which favors the formation and persistence of longer cloud rolls. Both factors contribute to a change in the time evolution of domain-mean water path and cloud core fraction of cloud streets. Our study takes advantage of the simulation driven by the differences between two large-scale forcing datasets to illustrate the importance of SST and wind direction shear in the cloud street morphology in a realistic scenario

Jingyi Chen↗

Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) Science Plan

Coastal cities provide the opportunity to characterize marine clouds and the substantial effects of manmade particles on cloud properties and processes. La Jolla lies to the north of San Diego, California, but it is often about a day directly downwind of the major pollution sources located in the ports of Los Angeles and Long Beach. The large dynamic range of aerosol particle concentrations combined with the multi-hour to multi-day persistence of stratocumulus cloud layers makes the site ideal for investigating the seasonal changes in cloud and aerosol properties as well as the quantitative relationships between cloud and aerosol properties. The focus of the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) is to characterize the extent, radiative properties, aerosol interactions, and precipitation characteristics of stratocumulus clouds in the Eastern Pacific across all four seasons at a coastal location, the Scripps Pier and the Scripps Mt. Soledad sites in La Jolla. An important enhancement to this study will be the collection of simultaneous in-cloud aerosol and droplet measurements to investigate the differences in these cloud properties during regional polluted and clean marine conditions. The combined observations will provide an unprecedented set of constraints for the following questions: 1. Cloud and Aerosol Climatology: What are the seasonal and diurnal cycles of marine stratocumulus cloud and aerosol properties on the northeastern Pacific coast? 2. Cloud Radiative Fluxes: How do cloud properties, including the ratio of direct-to-diffuse radiation, change as coastal clouds are advected inland? 3. Aerosol-Cloud Interactions: Will retrieved cloud properties reflect the regional signatures of aerosol?

Eastern Pacific Cloud Aerosol Precipitation Experi↗

Distribution and Sources of Tropospheric Aerosols Over the Western North Atlantic During ACTIVATE (February-March 2020)

The Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE) is a five-year (2019-2023) NASA Earth-Venture Suborbital-3 (EVS-3) mission to robustly characterize aerosol-cloud-meteorology interactions during February-June, with a focus on marine boundary layer clouds. This characterization requires understanding of aerosol composition, distribution, transport pathways, and sources. Here we use the GEOS-Chem chemical transport model driven by the MERRA-2 reanalysis to simulate tropospheric carbon monoxide (CO) and aerosols over the western North Atlantic Ocean (WNAO) during the first field deployment of ACTIVATE (February-March 2020). CO is used as a tracer to diagnose transport pathways for continental pollution outflow to the WNAO. The aerosol simulation represents all major aerosols including sulfate-nitrate-ammonium (SNA), mineral dust, sea salt, black and organic carbon aerosols. Model-simulated mixing ratios of SNA and organic carbon are compared with aircraft observations. We show that intensive aerosol mass measurements in the lower troposphere over the North American outflow region during ACTIVATE provide strong constraints on model aerosol wet scavenging. Comparisons of model aerosol extinctions with the airborne High Spectral Resolution Lidar-2 (HSRL-2) measurements indicate that the model generally captures continental outflow of aerosols and enhanced extinctions associated with sea salt. Simulated aerosol optical depths (AODs) and extinction vertical profiles are also compared with satellite retrievals from MODIS/Aqua and CALIOP/CALIPSO, respectively. CALIOP sometimes observes enhanced aerosol extinction at altitudes between ~1.5km and ~2.0km south of 32°N. The model reproduces this enhancement and attributes it to coarse-mode sea salt associated with high relative humidity. The relative contributions of continental and oceanic sources to the aerosol loading, AOD, and their distributions over the study domain will also be discussed.

aerosols↗