The dataset comprises the atmospheric boundary layer height (ABLH), the residual layer height (RLH) and the different types of aerosol optical depth (AOD) obtained over Grosseto, Italy. The data products were calculated on the basis of observations with CHM15k ceilometer and CE318 Sun-sky photometer. Data cover period starting at 00:00 UTC on 13th June until 23:00 UTC on 13th August 2018.
The data set consists of:
1. ABLH_RLH.zip: A folder with 42 ASCII (.txt) files, each for 24 hours of a single ceilometer observation day. If there was no observations on a certain day the data file was not created. Each file contains: the time (in UTC), the hourly-derived ABLH (in m a.g.l) and RLH (in m a.g.l.) with the standard deviation values STD (in m). The missing values are denoted with not-a-number (NaN). The ABLH and RLH were calculated by using the wavelet covariance transform method using Haar-form wavelet with a dilation of 30 m, applied over range and background corrected ceilometer signals averaged for temporal resolution of 30 min (15 min before and after each full-hour) and spatial resolution of 135 m. The ABLH is calculated for every hour of the day. The RLH is calculated as an additional layer above ABLH for every hour from 20:00 UTC to 6:00 UTC, at the height-ranges from 1.3 km to 3.4 km.
2. ABLH_figures.zip: A folder with 84 graphic (.png) files, each 2 files for 24 hours of a single ceilometer observation day, one figure with Y axis from 0 to 4 km a.g.l. and another figure with Y axis from 0 to 15 km a.g.l. for the same day. If there was no observations on a certain day the data file was not created. The graphics represent the time evolution (hour UTC in X axis) of the ceilometer range-corrected-signal (Pr2 in logarithmic color scale) with height (altitude a.g.l. in Y axis). The hourly retrieved ABLH are also plotted with red squares and hourly retrieved RLH are plotted with black dots, together with their standard deviations (as vertical lines). The ABLH and RLH were calculated by using the wavelet covariance transform method using Haar-form wavelet with a dilation of 30 m, applied over range and background corrected ceilometer signals averaged for temporal resolution of 30 min (15 min before and after each full-hour) and spatial resolution of 135 m. The ABLH is calculated for every hour of the day. The RLH is calculated as an additional layer above ABLH for every hour from 20:00 UTC to 6:00 UTC, at the height-ranges from 1.3 km to 3.4 km.
3. AOD_values.tab: An ASCII (.xlsx) file, that contains five different types of hourly-averaged AOD values (unitless) with uncertainties as well as percentage of AOD contributions for different atmospheric layers derived from combination of Sun-sky photometer and/or ceilometer. Time is given in UTC.
The different AODs are defined as:
o AODsun(1064nm) AE = 1.3: AOD values from Sun-sky photometer AERONET database scaled form 1020 nm (photometer wavelength) to 1064 nm (ceilometer wavelength) by using the power law with an assumed value for Angstrom exponent of 1,3. The resulting values are given as the hourly averages with the error calculated based on sensitivity study for different AE values. The error obtained from the sensitivity study with AE in (error_AODsun AE) column is 5%.
o AODcl(1064nm) rb = 0.5 LR = 50: AOD values obtained by integrating from the ground to the calibration height the ceilometer extinction profiles at 1064 nm derived by using the Klett method with the molecule-to-aerosol ratio rb = 0.5 and the lidar ratio LR = 50 sr. Below overlap range, each profile is extrapolated to the ground with the value of extinction obtained at the overlap maximum height. The two following columns list the errors calculated based on sensitivity study for different rb (error_AODcl rb) and LR (error_AODcl LR) values. The error obtained from the sensitivity study with rb in (error_AODcl rb) column is 20% and the error obtained from the sensitivity study with LR in (error_AODcl LR) is 50%.
o AODcorr: AOD values obtained when a correction is applied to AODcl (1064nm), and rest of parameters are set as in AODcl(1064nm) rb = 0.5 LR = 50. The correction was obtained by comparing a dataset of scaled AODsun (1064nm) values from Sun Photometer and coincident AODcl (1064nm) values from ceilometer, and thus accounts for the incomplete AOD estimation given by ceilometer. The following column list the uncertainties the AODcorr values, obtained by linear error propagation of the correction formula (error_AODcorr)
o AODcl(ABLH): AOD values obtained from AODcl(1064nm) by integrating profile from the ground up to the ABLH obtained for this profile. The two following columns list the errors calculated based on sensitivity study for different rb (error_AODcl(ABLH) rb) and LR (error_AODcl(ABLH) LR), being 20% and 50% respectively.
o AODcl(RLH): AOD values obtained from AODcl(1064nm) by integrating profile from the ground up to the RLH obtained for this profile, if any. The two following columns list the errors calculated based on sensitivity study for different rb (error_AODcl(RLH) rb) and LR (error_AODcl (RLH) LR), being 20% and 50% respectively.
Additionally, the percentage contributions of each AOD into different values was obtained:
o % AOD within ABLH (REF. CL): percentage of ceilometer-derived aerosol optical depth within the atmospheric boundary layer (AODcl(ABLH)) with respect to the ceilometer-derived aerosol optical depth (AODcl (1064nm) rb = 0.5 and LR = 50) for the entire profile up to the reference height.
o % AOD within ABLH (REF. SUN): percentage of ceilometer-derived aerosol optical depth within the atmospheric boundary layer (AODcl(ABLH)) with respect to the scaled Sun-sky photometer aerosol optical depth (AODsun (1064nm)) for the entire profile.
o % AOD within ABLH (REF. corr): percentage of ceilometer-derived aerosol optical depth within the atmospheric boundary layer (AODcl(ABLH)) with respect to the total AOD obtained from ceilometer after applying the correction (AODcorr).
o % AOD within RLH (REF. CL): percentage of ceilometer-derived aerosol optical depth within the residual boundary layer (AODcl(RLH)) with respect to the ceilometer-derived aerosol optical depth (AODcl (1064nm) rb = 0.5 LR = 50).
o % AOD within RLH (REF. corr): percentage of AOD within the RLH (AODcl(RLH)) with respect to the total AOD obtained from ceilometer after applying the correction (AODcorr).
Note: here is the link to the original Sun-sky photometer data files: https://aeronet.gsfc.nasa.gov/cgi-bin/webtool_aod_v3?stage=3®ion=Europe&state=Italy&site=Braccagni&place_code=10
ATTENTION:
We offer a free access to this dataset. The user is however encouraged to share the information on the data use with the Remote Sensing Laboratory by sending an e-mail to rslab@fuw.edu.pl.
In the case this dataset is used for a scientific communication (publication, conference contribution, thesis) we would like to kindly ask for considering to acknowledge the data provision by adding the following statement in Acknowledgments: "We acknowledge the data originators F. Mirza-Montoro, D. Wang, R. Fortuna, L. Alados-Arboledas, and I.S. Stachlewska for the acquisition, quality-assurance, evaluation, and provision of data sets within activities of the Remote Sensing Laboratory at the Faculty of Physics of the University of Warsaw, Poland and of the Atmospheric Research Group of the University of Granda, Spain."
(2022-07-29)