Mission
![]() |
The Atmospheric Optics Group of Valladolid University (GOA-UVa) is involved in the study of atmospheric components, mainly aerosols, with optical methods. The GOA calibration facility is devoted to radiometric calibration of optical instrumentations such as photometers, and it is part of the AERONET-Europe Central Facility, partially funded by the European Union. As a university group, our researchers carry out educational and training activity (graduate, master and PhD thesis). In this site you can find information about the work of the group, members, research lines, publications, projects, vacancies, etc. |
Latests Publications
2021 |
|
1. | AE Bedoya-Velásquez; M Herreras-Giralda; R Román; M Wiegner; S Lefebvre; C Toledano; T Huet; R Ceolato Ceilometer inversion method using water-vapor correction from co-located microwave radiometer for aerosol retrievals Journal Article Atmospheric Research, pp. 105379, 2021. @article{bedoya2021ceilometer, title = {Ceilometer inversion method using water-vapor correction from co-located microwave radiometer for aerosol retrievals}, author = {AE Bedoya-Velásquez and M Herreras-Giralda and R Román and M Wiegner and S Lefebvre and C Toledano and T Huet and R Ceolato}, doi = {10.1016/j.atmosres.2020.105379}, year = {2021}, date = {2021-03-01}, journal = {Atmospheric Research}, pages = {105379}, publisher = {Elsevier}, abstract = {Recent ceilometer models are more sensitive to aerosols, which is increasing the interest in these instruments to retrieve aerosol optical and microphysical properties. In this paper, a new methodology is proposed to retrieve aerosol vertical extinction and backscatter profiles from a Vaisala ceilometer CL51 model. This methodology is based in two parts: first, a signal pre-processing with a suppression of the dark current and background noises, and a correction of the water vapor absorption using near-real-time temperature and absolute humidity (AH) profiles from a co-located Microwave radiometer (MWR). The measured dark current shows a height-dependence from 11?km agl to the end of the profile. From the water vapor correction, it was seen that the raw ceilometer signal overestimates the water vapor corrected one, mainly below 1?km agl. Second part is based on an iterative Klett-based algorithm making use of AERONET (AErosol RObotic NETwork) AOD (Aerosol Optical Depth) and ceilometer profiles as inputs to retrieve the extinction and backscatter profiles. The sensitivity of the aerosol retrievals to the use of modelled temperature and absolute humidity from HYSPLIT to correct water vapor absorption, instead of MWR measurements, is studied. The absolute errors found in temperature and AH profiles leads to errors in the pre-processed range corrected signals up to 9%, and then in particle backscatter (?p) and particle extinction (?p) coefficients up to 2.2 % and 25 %, respectively.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Recent ceilometer models are more sensitive to aerosols, which is increasing the interest in these instruments to retrieve aerosol optical and microphysical properties. In this paper, a new methodology is proposed to retrieve aerosol vertical extinction and backscatter profiles from a Vaisala ceilometer CL51 model. This methodology is based in two parts: first, a signal pre-processing with a suppression of the dark current and background noises, and a correction of the water vapor absorption using near-real-time temperature and absolute humidity (AH) profiles from a co-located Microwave radiometer (MWR). The measured dark current shows a height-dependence from 11?km agl to the end of the profile. From the water vapor correction, it was seen that the raw ceilometer signal overestimates the water vapor corrected one, mainly below 1?km agl. Second part is based on an iterative Klett-based algorithm making use of AERONET (AErosol RObotic NETwork) AOD (Aerosol Optical Depth) and ceilometer profiles as inputs to retrieve the extinction and backscatter profiles. The sensitivity of the aerosol retrievals to the use of modelled temperature and absolute humidity from HYSPLIT to correct water vapor absorption, instead of MWR measurements, is studied. The absolute errors found in temperature and AH profiles leads to errors in the pre-processed range corrected signals up to 9%, and then in particle backscatter (?p) and particle extinction (?p) coefficients up to 2.2 % and 25 %, respectively. |
2. | Juan Carlos Antuña-Sánchez; René Estevan; Roberto Román; Juan Carlos Antuña-Marrero; Victoria E Cachorro; Albeth Rodríguez Vega; Ángel M de Frutos Solar Radiation Climatology in Camagüey, Cuba (1981–2016) Journal Article Remote Sensing, 13 (2), 2021, ISSN: 2072-4292. @article{rs13020169, title = {Solar Radiation Climatology in Camagüey, Cuba (1981–2016)}, author = {Juan Carlos Antuña-Sánchez and René Estevan and Roberto Román and Juan Carlos Antuña-Marrero and Victoria E Cachorro and Albeth Rodríguez Vega and Ángel M de Frutos}, url = {https://www.mdpi.com/2072-4292/13/2/169}, doi = {10.3390/rs13020169}, issn = {2072-4292}, year = {2021}, date = {2021-01-01}, journal = {Remote Sensing}, volume = {13}, number = {2}, abstract = {The transition to renewable energies is an unavoidable step to guarantee a peaceful and sustainable future for humankind. Although solar radiation is one of the main sources of renewable energy, there are broad regions of the planet where it has not been characterized appropriately to provide the necessary information for regional and local planning and design of the different solar powered systems. The Caribbean, and Cuba in particular, lacked until very recently at least one long-term series of surface solar radiation measurements. Here we present the first long-term records of solar radiation for this region. Solar radiation measurements manually conducted and recorded on paper were rescued, reprocessed and quality controlled to develop the solar radiation climatology at the Actinometrical Station of Camagüey, in Cuba (21.422°N; 77.850°W; 122 m a.s.l.) for the period 1981–2016. The diurnal cycle based on the average hourly values of the global, direct and diffuse horizontal variables for the entire period have been determined and analyzed showing the dependence on solar zenith angle (SZA) and clouds. The annual cycle of global solar component given by the mean monthly daily values presents two maxima, one in April and another one in July with values of 5.06 and 4.91 kWh m−2, respectively (18.23 and 17.67 MJ m−2 per day for insolation), and the minimum in December (3.15 kWh m−2 or 11.33 MJ m−2). The maxima are governed by the direct solar components and are modulated by cloudiness. Both, diurnal and annual cycles of the diffuse solar component show a smoothed bell shaped behavior. In general solar radiation at this station presents a strong influence of clouds, with little seasonal variation but with higher values during the rainy season. Daily global radiation annual averages showed its maximum value in the year 1983, with 17.45 MJ m−2 explained by very low cloudiness this year, and the minimum value was reported in 2009 with a value of 12.43 MJ m−2 that could not explained by the cloud coverage or the aerosols optical depths registered that year. The effects of the 1982 El Chichón and 1991 Mount Pinatubo volcanic eruptions on the solar radiation variables at Camagüey are also shown and discussed. The results achieved in this study shown the characteristics of solar radiation in this area and their potential for solar power applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The transition to renewable energies is an unavoidable step to guarantee a peaceful and sustainable future for humankind. Although solar radiation is one of the main sources of renewable energy, there are broad regions of the planet where it has not been characterized appropriately to provide the necessary information for regional and local planning and design of the different solar powered systems. The Caribbean, and Cuba in particular, lacked until very recently at least one long-term series of surface solar radiation measurements. Here we present the first long-term records of solar radiation for this region. Solar radiation measurements manually conducted and recorded on paper were rescued, reprocessed and quality controlled to develop the solar radiation climatology at the Actinometrical Station of Camagüey, in Cuba (21.422°N; 77.850°W; 122 m a.s.l.) for the period 1981–2016. The diurnal cycle based on the average hourly values of the global, direct and diffuse horizontal variables for the entire period have been determined and analyzed showing the dependence on solar zenith angle (SZA) and clouds. The annual cycle of global solar component given by the mean monthly daily values presents two maxima, one in April and another one in July with values of 5.06 and 4.91 kWh m−2, respectively (18.23 and 17.67 MJ m−2 per day for insolation), and the minimum in December (3.15 kWh m−2 or 11.33 MJ m−2). The maxima are governed by the direct solar components and are modulated by cloudiness. Both, diurnal and annual cycles of the diffuse solar component show a smoothed bell shaped behavior. In general solar radiation at this station presents a strong influence of clouds, with little seasonal variation but with higher values during the rainy season. Daily global radiation annual averages showed its maximum value in the year 1983, with 17.45 MJ m−2 explained by very low cloudiness this year, and the minimum value was reported in 2009 with a value of 12.43 MJ m−2 that could not explained by the cloud coverage or the aerosols optical depths registered that year. The effects of the 1982 El Chichón and 1991 Mount Pinatubo volcanic eruptions on the solar radiation variables at Camagüey are also shown and discussed. The results achieved in this study shown the characteristics of solar radiation in this area and their potential for solar power applications. |
2020 |
|
3. | A. Barreto; R. Román; N. Prats; A. Lopatin; D. Fuertes; A.J. Berjón; F. Almansa; E. Cuevas; M. Yela. Aerosol Profiles From MPL-Lidar And Photometric Measurements Using GRASP In A Subtropical North Atlantic Site. Evaluation With In-Situ Data. Conference European Lidar Conference 2020 (ELC 2020), University of Granada Granada, Spain, 2020. @conference{Barreto2020, title = {Aerosol Profiles From MPL-Lidar And Photometric Measurements Using GRASP In A Subtropical North Atlantic Site. Evaluation With In-Situ Data.}, author = {A. Barreto and R. Román and N. Prats and A. Lopatin and D. Fuertes and A.J. Berjón and F. Almansa and E. Cuevas and M. Yela.}, year = {2020}, date = {2020-11-13}, booktitle = {European Lidar Conference 2020 (ELC 2020)}, address = {Granada, Spain}, organization = {University of Granada}, keywords = {}, pubstate = {published}, tppubtype = {conference} } |
4. | L. Alados-Arboledas; R. Román; J.A. Benavent-Oltra; A. Cazorla; J.A. Casquero-Vera; G. Titos; H. Lyamani; P. Ortíz-Amezcua; G.A. Moreira; A.E. Bedoya-Velasquez; D. Pérez-Ramírez; J.L. Guerrero-Rascado; F.J. Olmo Assessment of the atmospheric aerosol properties retrieved by GRASP algorithm during SLOPE II campaign Conference European Lidar Conference 2020 (ELC 2020), Universidad de Granada Granada, Spain, 2020. @conference{Alados-Arboledas2020, title = {Assessment of the atmospheric aerosol properties retrieved by GRASP algorithm during SLOPE II campaign}, author = {L. Alados-Arboledas and R. Román and J.A. Benavent-Oltra and A. Cazorla and J.A. Casquero-Vera and G. Titos and H. Lyamani and P. Ortíz-Amezcua and G.A. Moreira and A.E. Bedoya-Velasquez and D. Pérez-Ramírez and J.L. Guerrero-Rascado and F.J. Olmo }, year = {2020}, date = {2020-11-13}, booktitle = {European Lidar Conference 2020 (ELC 2020)}, address = {Granada, Spain}, organization = {Universidad de Granada}, keywords = {}, pubstate = {published}, tppubtype = {conference} } |
5. | D. Mateos; V.E. Cachorro; C. Velasco-Merino; N.T. O'Neill; M.A. Burgos; R. Gonzalez; C. Toledano; M. Herreras; A. Calle; A.M. de Frutos Comparison of three different methodologies for the identification of high atmospheric turbidity episodes Journal Article Atmospheric Research, pp. 104835, 2020. @article{Mateos2020b, title = {Comparison of three different methodologies for the identification of high atmospheric turbidity episodes}, author = {D. Mateos and V.E. Cachorro and C. Velasco-Merino and N.T. O'Neill and M.A. Burgos and R. Gonzalez and C. Toledano and M. Herreras and A. Calle and A.M. de Frutos}, doi = { 10.1016/j.atmosres.2019.104835}, year = {2020}, date = {2020-06-01}, journal = {Atmospheric Research}, pages = {104835}, publisher = {Elsevier}, keywords = {}, pubstate = {published}, tppubtype = {article} } |