This file was assembled by Stuart Batterman on 6/30/2020 and describes data for the GEOHEALTH journal paper entitled:  Air Quality Impacts at an E-Waste Site in Ghana using Flexible, Low-Cost and Quality Assured Measurements.

The archived data in Deep Blue contains two files.

=============== File 1:  Fixed_Site_Consol_1_Values.xlsx ===============================

The Fixed_Site_Consol_1.xlsx Excel file contains (nominally) 24-hour average pollution data collected from February 2017 through February 2018 at three sites established around the Agbogbloshie E-waste site, and meteorological data obtained from the Kotoka International Airport site, both in Accra, Ghana.

The 24-hour period is the nominal duration of the sample.  The actual collection times are provided in the excel file. 

The variables in the data are described below.  Missing data is indicated by a blank.

SITE-Des: Name for Sample Number, including a prefix U, M or L, which designates the site as Upwind, Mosque or Letap.   This corresponds also to SITE_ID (as described below).  The numeric portion is a sample number.

Site_ID: Site identifier as site 1, 2, 3 = Upwind, Mosque and Letap

Deploy_Date:  Deployment date for filter and optical samplers.  This data and the following dates and times are from the technician’s logs.

Deploy_Time: Deployment time (local)

Retreive_Date: Retrieval date for filter and optical samplers

Retrieve_Time: Retrieval time (local)

PM_Grav_Duration: Calculated or estimated duration of gravimetric sample in hours

PM2.5_Grav_Conc:  Concentration of airborne particulate matter under 2.5 micrometers in dia (PM2.5) in ug/m3 based on filter measurements using the SKC Impact Sampler and a nominal flow rate of 10 L/min over the deployment period 

PM_Opt_Duration:  Number of hours that optical measurements were available for the sample.  Applies to PM2.5_Opt_Conc and PM10_Opt_Conc. 

PM2.5_Opt_Conc:  Concentration of PM2.5 in ug/m3 based on Aerocet 831 unadjusted value.

PM10_Opt_Conc:  Concentration of PM10 (particulate matter below 10 micrometer dia) in ug/m3 based on Aerocet 831 unadjusted 

PM2.5_Opt_Conc_Sim:  Optical PM2.5 concentration in ug/m3 based on Aerocet 831 if Aerocet period is at least 80% of the PM_Grav_Duration period, i.e., values that overlap.

The following data is taken from the Kotoka International Airport and represent the average or number hourly measurements, as available, for the nominally 24-hour sampling period.

RH_Count: Number of hours of RH measurements during period

RH_Ave: Average relative humidity at airport in %

RH_Ave_Trim: Trimmed mean (10% off each tail) for relative humidity in %

RH_90th: 90th percentile of relative humidity for period in %

Temp_Count: Number of hours with temperature measurements during period

Temp_Ave: Average temperature at airport (Kotoka) in degrees C



=============== File 2:  Ghana_PM_Hourly_Data_1_Values.xlsx ===============================

The Ghana_PM_Hourly_Data_1_Values.xlsx Excel file contains (nominally) 1-hour average pollution data collected from February 2017 through February 2018 at three sites established around the Agbogbloshie E-waste site.

The 1-hour period is the nominal duration of the sample.   Samples utilize 45 to 60 minutes of data collected in the hour.  Fewer than 45 minutes of data is not considered valid and is a missing value in the dataset, marked with an empty cell.  While each hour of 2017 and 2018 are listed, data were obtained for only a subset of hours.

The variables in the data are described below.  Missing data is indicated by a blank.

Calendar: Date and time at beginning of sample.  Uses local Ghana time.

The next 9 columns are 1-hr averages that measure PM2.5, PM10 and PM2.5-10 ambient concentrations at three sites using the MetOne Aerocet 831 instrument.   PM2.5 is particulate matter below 2.5 micrometers in diameter;  PM10 is particulate matter below 10 micrometers in diameter, and PM2.5-10 is particulate matter from 2.5 to 10 micrometers in diameter, obtained by differencing, which is also called the "coarse fraction".  All measurements are in ug/m3.  Sites 1, 2 and 3 are respectively the upwind, Mosque and Letap sites, as described in the paper.   These variables in the data set are:

PM2.5_Site1_1hrAve: PM2.5, Site 1

PM2.5_Site2_1hrAve: PM2.5, Site 2

PM2.5_Site3_1hrAve: PM2.5, Site 3

PM10_Site1_1hrAve: PM10, Site 1

PM10_Site2_1hrAve:PM10, Site 2

PM10_Site3_1hrAve:PM10, Site 3

PM2.5-10_Site1_1hrAve: PM2.5 to PM10 (coarse fraction), Site 1

PM2.5-10_Site2_1hrAve: PM2.5 to PM10 (coarse fraction), Site 2

PM2.5-10_Site3_1hrAve: PM2.5 to PM10 (coarse fraction), Site 3