1. PROJECT (PhD Thesis) ------------ Title: Investigating the electrical modification of fog in the UAE Dates: 02/21 – 04/23 Locations: -Sanad Academy, Dubai, UAE (24°56' N, 55°30' E) -Al Marmoom (automatic weather station-AWS), Dubai, UAE (25°00' N, 55°30' E) 2. DATASET ------------ Title: Dataset for PhD Thesis 'Investigating the electrical modification of fog in the UAE' Description: This dataset contains potential gradient (PG), visibility, droplet/aerosol number concentration and size distribution, and standard meteorological data used in PhD thesis 'Investigating the electrical modification of fog in the UAE' by Ahmad Alkamali (2025). The primary measurements were obtained at Sanad Academy, Dubai, United Arab Emirates (UAE) (24°56' N, 55°30' E) starting from February 2021 till April 2023. Standard meteorological data where obtained from Al Marmoom, Dubai, UAE (25°00' N, 55°30' E) from February 2021 till February 2022. The data has been used to study the electrical properties of different weather conditions, with a focus on fog in the UAE, as well as to understand the effects of charge emissions on the PG and fog microphysics. The electric field was measured using a Campbell CS110 electric field mill at a height of 3m (which was then converted to potential gradient using electric field = -potential gradient). Visibility was measured using a Biral SWS-100 visibility sensor mounted on the same mast as the CS110. Droplet/aerosol number concentration and size distribution was measured using a MeteoModem light optical aerosol counter (LOAC). Note: Some data gaps are present due to sensor and connection issues. Final version submission Year: 2025 Creator: Ahmad Alkamali Organisation(s): University of Reading / National Center of Meteorology, UAE. Rights-holder(s): Ahmad Alkamali Cite as: Alkamali, Ahmad (2025): Dataset for PhD thesis: "Investigating the electrical modification of fog in the UAE". University of Reading. Dataset. https://doi.org/10.17864/1947.001427 Related publication: Alkamali, Ahmad A., Ambaum, Maarten H. P. and Nicoll, Keri A. (2024) Electrical measurements during fog in the United Arab Emirates. Atmospheric Research, 307. 107469. DOI: https://doi.org/10.1016/j.atmosres.2024.107469 3. TERMS OF USE ----------------- Copyright 2025 Ahmad Alkamali. This dataset is licensed by the rights-holder(s) under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/. 4. CONTENTS ------------ Four zip folders are included within the dataset: Folder 1:Sanad_2021.zip Folder 2:2022_data_1.zip Folder 3:2022_data_2.zip Folder 4:2023_data.zip The contents of each folder will now be described below. Folder 1: Contains monthly potential gradient (PG) and visibility data (from Sanad Academy), as well as standard meteorological data (wind speed [km/h], wind direction, RH [%], temperature [DegC], and dew point temperature [DegC]) from Al Marmoom AWS for the year 2021 (starting from February 2021). Files are organised by month, with all data measured at 1-minute resolution. Folder 2: Contains raw electric field data for the year 2022 (starting from January 2022), raw standard meteorological data from Al Marmoom AWS, and raw data from LOAC, which includes number concentration for different particle sizes (ranging from 0.2 microns to 30 microns), typology classified by size (e.g., salts, water droplets, carbon, minerals, and others), and Mass concentrations (including: PM 1, 2.5, 4, 10 and 20). Efield raw data presented here measured at 1-second resolution, while it was 15-minutes resolution for standard meteorological data, and 1-minute resolution for LOAC data. Notes: Some gaps in data are present due to sensor and connection issues. LOAC had operational issues early in the year and resumed proper function again in September 2022. Between March and June 2022, the ionisers were installed in the field (active between 04 and 08 UAE LT) for functionality tests, thus, oscillations may be observed especially when analyzing the electric field data during this period. Folder 3: Contains raw visibility data for the year 2022 (starting from January 2022), and raw standard meteorological data from MaxiMet GMX-600 at Sanad Academy. All raw data presented here are measured at 1-minute resolution. Notes: Some gaps in data are present due to sensor and connection issues. The MaxiMet GMX-600 began functioning properly on 22nd January 2022. Folder 4: Contains raw electric field data for the year 2023, raw standard meteorological data from the GMX-600 at Sanad Academy, raw visibility data, and raw LOAC data, which includes number concentration for different particle sizes (ranging from 0.2 microns to 30 microns), typology classified by sizes (e.g., salts, water droplets, carbon, minerals, and others), and Mass concentrations (including: PM 1, 2.5, 4, 10 and 20). Efield raw data presented here measured at 1-second resolution, while it was 1-minute resolution for the standard meteorological data, LOAC data, and visibility data. Notes: Data presented here where collected during the introduction of artificial ion emission, which occurred automatically between 04 and 08 UAE LT (mainly). Due to previous operational issues, the LOAC was only installed when fog was forecasted, where it was typically set up the night before and removed in the following morning. 5. METHOD and PROCESSING -------------------------- Most data provided are the raw data from the sensors, except the potential gradient and standard meteorological data in Folder 1 which were averaged to 1 minute mean values. For each of the different measurement types, details of the sensors used and a link to the manufacturer user manuals is provided below. Electric field was measured by a Campbell CS110 electric field mill at 3m height. https://s.campbellsci.com/documents/us/manuals/cs110.pdf Visibility was measured by a Biral SWS-100 visibility sensor on the same mast as the CS110. https://www.biral.com/wp-content/uploads/2018/02/SWS-Manual-105223.08B.pdf Droplet/aerosol number concentration and size distribution was measured using a LOAC. http://leaflet.meteomodem.com/LOAC%20TELEMETRY%20EN.pdf Standard meteorological data at Sanad Academy with measured using MaxiMet GMX-600. https://gillinstruments.com/wp-content/uploads/2024/02/1957-010-MaxiMet-GMX600-Issue-12.pdf