1. Introduction
The founding of the Royal Observatory of Belen College (ROBC) in 1858 marked the origin of atmospheric research in Cuba. Its most relevant scientists were Spanish: Father Benito Viñes Martorell (Catalonia, 1837-Havana, 1893) and Mariano Gutiérrez-Lanza Díez (León, 1865-Havana, 1943) (Ramos Guadalupe 2014a,b). The Havana Physical Meteorological Observatory (HPMO) was founded in 1862, with Cuban scientist Andrés Poey Aguirre (1825–1919) as its head. ROBC observations and research foci were tropical cyclones and geomagnetism, while HPMO focused on solar radiation polarization, ozone, and optical phenomena. Unfortunately, despite their complementarities and synergies, the cooperation between Cuban and Spanish scientists did not materialize at that time. One and half century later, in 2008, Cuban and Spanish scientists began official cooperation in atmospheric optics research, pursuing common interests and mutual benefits, which continues to this day.
The Camagüey Lidar Station (CLS) started in 1988, when a stratospheric aerosol lidar was set up at Camagüey, Cuba, in cooperation with the former Soviet Union. Located at the Camagüey Provincial Meteorological Center (CMPC), the CLS survived the U.S. government blockade against Cuba and the disintegration of the Soviet Union, allowed transitioning into Camagüey Atmospheric Optics Group (GOAC) two decades later (Antuña-Marrero et al. 2012). This was accomplished by a joint definition by the team of its working goals; prioritizing capacity building (instruments and know-how); seizing international cooperation opportunities; and aligning the team goals, to confront the lack of hard currency funds and expertise. Cooperation took place in that period with scientists and research teams in several countries, including half a decade cooperation of CLS and GOAC (hereinafter CLS/GOAC) with the Atmospheric Optics Group of the University of Valladolid (GOA-UVa), Spain. However, more scientific results were achieved in the next decade, including the transition of GOAC to the Departamento de Radiación Solar y Óptica Atmosférica (DRSOA), in 2022, motivating this article.
An additional motive is the scientific community concern about “parachute” scientific cooperation (e.g., Genda et al. 2022; Rayadin and Buřivalová 2022), in which developed country scientists carrying out research in underdeveloped countries do not recognize the important contribution of the local scientists and infrastructure of these countries and fail to establish long-term cooperation. None of the international CLS/GOAC cooperation actions match this type, with the GOA-UVa cooperation being the best example. We outline the scientific results obtained with mutual consensus, interests, and benefits, resulting in instrumental capabilities that were developed and knowledge transfer remaining rooted in local scientific personnel. There is another cooperation activity, with similar features, between the Center for Environmental Studies of Cienfuegos, Cuba, and the University of Navarra, Spain. They conduct PM10 and PM2.5 samplings from 2015 to 2023, respectively. Morera-Gómez et al. (2018) reported the first results followed by seven more peer-reviewed articles (Y. Morera-Gómez 2023, personal communication).
2. The origin of the cooperation
GOA-UVa, set up in 1995 by the initiative of Ángel de Frutos and Victoria Cachorro, conducts research on aerosols, solar radiation, and atmospheric components. The team accumulates broad expertise in optical instruments, radiometry, spectroscopy, sky cameras, and other optical techniques including instrument design and construction. In 2000, GOA-UVa, in cooperation with the Instituto Nacional de Tecnología Aeroespacial, Spain, set up at El Arenosillo (Huelva) the first AERONET (Holben et al. 1998) site in Spain, and an optical and aerosol calibration laboratory. Since 2003, GOA-UVa conducted several joint projects with the Centro de Investigaciones Atmosféricas de Izaña (CIAI), developing an optical calibration laboratory for solar radiation instruments at Izaña Observatory. CIAI and GOA-UVa are sun photometer calibration platforms from Aerosols, Clouds, and Trace Gases Research Infrastructure (ACTRIS) (https://www.actris.eu/), federated with AERONET. Because of its scientific achievements, GOA-UVa has been in the University of Valladolid Recognized Research Group category since 2000. They have also been in the Junta de Castilla y León Research Group of Excellence category since 2006, which under new regulations changed to Consolidated Research Unit category from 2015 to the present.
CLS/GOAC requested article copies by mail or email, to cope with the lack of scientific bibliography, including GOA-UVa leaders. They answered, providing the requested articles. In Madrid, at the 2003 European Aerosol Conference, the first personal exchange took place finding common scientific interests. New contacts at several meetings ended in a lead author visit to GOA-UVa in October 2005, resulting in a Letter of Intent signed by the team leaders. They proposed to UVa and the Institute of Meteorology (INSMET) of Cuba an official cooperation agreement to conduct research of the optical and physical properties of aerosols in Cuba. It was signed 2 years later, in September 2007, during a visit by Ángel de Frutos to CLS. Its goals were, installing a sun photometer and a cascade impactor at CLS; designing and building two tropospheric aerosols lidar systems, for CLS and the El Arenosillo AERONET site, Spain; and executing joint research projects with those instruments and satellite observations. Given the agreement’s success, a new clause in 2013 set up automatic renewal unless terminated by one of the parties.
3. Instrument setup
In 2007, the CLS personnel were René Estevan, Boris Barja, and Juan Carlos Antuña-Marrero. The first two, working on their PhDs under the advice of the third, focused on evaluating the surface radiative forcing by stratospheric aerosols from the 1991 Mt. Pinatubo eruption and by cirrus clouds, respectively. The tasks assigned to execute the cooperation agreement considered their expertise’s assigning Barja the impactor full responsibility and Estevan the sun photometer. Their PhD theses were defended successfully in 2009 (Estevan 2009; Estevan and Antuña-Marrero 2010) and 2010 (González 2010; Barja and Antuña-Marrero 2011).
Sandra Mogo, from the Universidade da Beira Interior (UBI), Covilhã, Portugal, designed and built the particulate matter (PM) PM10 and PM1 sampling system. She advised Cubans on its installation, sampling method, filter preparation, transportation, weighing, and preservation for chemical and optical properties analysis. She also measured sample spectral absorption coefficients using the Integrating Sphere Spectral System method developed at UBI in cooperation with GOA-UVa, which also contributed funding (Montilla et al. 2011).
In December 2007, the DEKATI PM10 and PM1 low volume cascade PM impactor arrived in Camagüey. Cubans conditioned the site and installed the impactor on 7 February 2008. Due to the lack of a microbalance at Camagüey, the samples were weighed at the National Institute of Hygiene, Epidemiology, and Microbiology (INHEM), in Havana City. Due to a breakdown of the analytical microbalance at INHEM, gravimetric observations ended in October that year. However, sample collection continued, for chemical composition and optical aerosol absorption determinations until April 2009. In addition, samples were collected for two different periods during 2010 and from 2012 to 2014 (Barja et al. 2011, 2013; Mogo et al. 2019). The second shipment, in August 2008, carried the CIMEL-318 sun photometer, the AERONET standard. Installed on 7 October 2008 (Fig. 1), it began observations and real-time data transmission to Red Ibérica de Medida fotométrica de Aerosoles (RIMA) and AERONET.
The CLS observation site after completing installation of two instruments on 7 Oct 2008. The impactor is inside the circular housing. Its aerosol inlet is on the top left and the AERONET sun photometer is on the top right. From the left, Rene Estevan and Boris Barja.
Citation: Bulletin of the American Meteorological Society 106, 2; 10.1175/BAMS-D-23-0138.1
4. Scientific investigations and associated results
Cuban scientists began processing and analyzing observations in 2009, keeping regular exchanges with the Spanish. The results, presented at international conferences and published, are summarized below grouped by topics, and a final section highlights the most significant ones.
a. Aerosol optical properties.
During the first years, several preliminary studies were carried out to develop the capacity of Cuban researchers in the use of aerosol property observations from CALIOP and MODIS satellite instruments. Upon completion of the first year of observations with the sun photometer in 2009, the preliminary characterization of local aerosol properties classified them as predominantly mixed maritime, with the presence of Saharan dust in summer. Multiple Saharan aerosol events were identified in 2009 by back trajectory analysis using the sun photometer AOD at the 500-nm wavelength (AODSP500) and the HYSPLIT model (Estevan et al. 2011). The AODSP500 series for July 2009 was compared with coincident AOD at 500 nm (AOD500) forecasted by the SKIRON model (Kallos et al. 2009) and AOD at 550 nm (AOD550) from MODIS, both Terra and Aqua. Predicted Saharan dust AOD500 values were higher than AODSP500. Terra and Aqua AOD550 underestimated the highest AODSP500 and overestimated the lowest (Antuña et al. 2012). Also, the broadband AOD (Fonte and Antuña 2011) was validated with the AODSP at seven wavelengths. Both AODSP500 and AODSP675 with R2 = 0.45 were the best matches (García et al. 2015).
CLS/GOAC and the Instituto di Metodologie per l’Analisi Ambientale, Italy, funded by ACTRIS in 2014, studied the longest Saharan dust event in Camagüey, 15–20 July 2009, with a maximum AODSP500 of 0.65. AODSP500 was compared with CALIOP AOD532 and AOD550 from Terra and Aqua. The results show good agreement between CALIOP and both MODIS instruments. However, CALIOP and MODIS instruments underestimated the highest values of the AODSP500 (Estevan et al. 2014).
A new comparison of the sun photometer AODSP and Ångström exponent (AESP) at Camagüey and AOD550 and AE from Terra and Aqua was conducted, including the combined AOD550 and AE from Terra and Aqua and the ones from the deep blue (DB) and dark target (DT) MODIS Collection 6. Results showed that the DT algorithm performed better than DB and small differences between Terra and Aqua AOD, allowing them to be combined for climatological studies. Linear correlations revealed MODIS AOD slightly overestimates the AODSP, and AOD550 regression slopes with AODSP close to 1, a good correlation. The MODIS AE comparison results confirmed its limited representativity already shown in previous studies (Antuña-Marrero et al. 2018).
In 2019, CLS/GOAC and the Stratospheric and Tropospheric Research and Modeling group (https://stream-ucm.es/) at the Universidad Complutense de Madrid (UCM) began a climatological study of aerosol properties in the Caribbean islands. The study characterized aerosol types, transport paths, and associated synoptic patterns using AODSP440 and AESP at the AERONET stations at Ragged Point (Barbados), Guadeloupe, La Parguera (Puerto Rico), and Camagüey. The results verified a secondary AODSP440 maximum at Camagüey in the dry season already reported by García et al. (2015) and not present in the rest of the Caribbean stations. Figure 2 shows for each site the back-trajectories for the 7 days prior to the first day of the marine aerosol episodes in the dry season. At Camagüey, unlike most of the Caribbean, back-trajectories originate in North America, explaining the secondary maximum by the transport of aerosols from North America, likely of anthropogenic origin. It was also found that coarse aerosols predominate in the Caribbean basin throughout the year, due to predominant marine aerosols in the dry season and dust aerosols in the rainy season. The coarse aerosol spatial distribution has a latitudinal gradient with higher frequency in eastern islands, decreasing toward the west. The most heterogeneous aerosol composition, a mixture of continental aerosols, anthropogenic pollution, and desert aerosol, is at Camagüey, and second at La Parguera, the only two stations with detectable biomass burning aerosols. The frequencies of aerosol type among the stations are mainly associated with their distances from the ocean and to North America and Cuba’s spatial extent (Rodríguez-Vega et al. 2022a).
Composites of geopotential height (shading; m) and wind vector (arrows) anomalies at 850 hPa for the first day of marine aerosol episodes in the dry season at each Caribbean station. Contours show the mean geopotential height at 850 hPa for the composite days (m). The three colored lines indicate the mean backward trajectories arriving at 500 m (green), 1500 m (magenta), and 3000 m (brown), with colored dots denoting the mean positions for each day of the 7- day backward trajectories. The number of cases employed in the composite with respect to the total number of days with that aerosol is shown in parentheses in the top right of each panel. (Rodríguez Vega et al. 2022a) © American Meteorological Society. Used with permission.
Citation: Bulletin of the American Meteorological Society 106, 2; 10.1175/BAMS-D-23-0138.1
b. PM, aerosol chemical composition, and optical absorption properties.
PM observations in Camagüey, from February to October 2008, were conducted both in background conditions and in Saharan dust events. The mean (standard deviation) PM concentration values were 27.92 (11.96) μg m−3 and 14.55 (5.29) μg m−3 for PM10 and PM1, respectively. The PM levels dependence on wind direction found southwest wind associated with high PM levels and northwest winds with low PM levels (Barja et al. 2011).
The next study used results of chemical and absorption analysis of PM samples from February 2008 to April 2009. Eight main inorganic species (Na+, K+, Ca2+, Mg2+, NH4+, Cl−, NO3−, and
A new study showed the behavior of σa from PM1 fractions during 2010 and 2012–14. The mean values of σa were 14.99, 14.50, and 13.15 Mm−1 for 450, 550, and 700 nm, respectively. The absorption spectral shape in the case of σa decreased rapidly in the blue-green range and dropped slowly in the green-red range. Local aerosols have σa variable spectral features, with high values of αa, for the lower absorbing particles and low values of αa for the higher absorbing. These results, for σa and αa, are unique in Camagüey, Cuba, and the Caribbean region (Mogo et al. 2019).
The University of Sao Paulo, Brazil Institute of Physics, contributed to the analysis of the samples collected in Camagüey, providing access to a microbalance and Energy Dispersive X-Ray Fluorescence equipment. The contribution allowed us to perform gravimetric and chemical speciation analysis of PM1 samples collected in 2010 and from 2012 to 2014. They also transferred know-how of the principal component analysis method for the source distribution study (Barja et al. 2013).
c. Optical properties of clouds.
Camagüey was among the AERONET sites selected to implement “cloud mode” observations (Chiu et al. 2010). After 1 year of observations, June 2010–May 2011, a study of cloud optical depth (COD) was conducted. The monthly mean COD maximum was 34.2 in May, and the minimum was 19.8 in December. A comparison using time coincident cloud reports from the local meteorological station identified the 98.8% of the COD observations as clouds also in the reports. All the rejected cases were low COD values and no clouds in the zenith in the report. The most probable reason was the presence of subvisible cirrus clouds in those cases. COD values ≤ 5 were compared with the CALIOP COD the same days and located in a ±1° box of latitude and longitude around the site. The COD frequency distributions for almost 400 coincidence cases of both instruments were similar (Barja et al. 2012).
Another study evaluated the cloud radiative effect (CRE) at the surface in Camagüey, using two methods to estimate CRE. The first (hereinafter CRE0) uses the COD around noon of the 6-yr period from June 2010 to May 2016 as input to the GFDL Radiative Transfer Model 1D (Freidenreich and Ramaswamy 2005). GOAC has already tested the GFDL model for clear and cloudy sky conditions at Camagüey using local solar radiation observations (Barja and Antuña-Marrero 2011). Those observations were used in the second method (Antuña et al. 2008) to determine CRE (CREm) the same days the CODs were available and to identify cumulus (Cu) and mixed stratocumulus–cumulus (Sc–Cu) cloud types. Maximum frequencies of CREm and CRE0 are in the ranges of −400 to −500 W m−2 for Cu clouds and −300 to −400 W m−2 for Sc–Cu clouds. The maximum shortwave cloud effect efficiency (CEE) for Cu clouds was −29 W m−2 per unit COD, with the COD value of 5.3 and cosine of zenith solar angle (CSZA) of 0.91. For the Sc–Cu clouds, the maximum CEE was −22 W m−2 per unit COD, with the COD value of 7.1 and CSZA of 0.95. The shortwave cloud efficiency effect for the two cloud types decreases notably with the increasing COD value up to 20. For larger COD, the CEE is less sensitive to increasing COD (Barja et al. 2023). This characterization of COD, its CRE and CEE, is unique so far in Camagüey and Cuba (Barja et al. 2023).
d. All-sky cameras for cloud and aerosol properties research.
In 2014, the CLS/GOAC built a low-cost all-sky camera for cloud research. The GOA-UVa provided a Raspberry Pi, its camera module, and complementary metal oxide semiconductor (CMOS) sensor. John Braun at UCAR, who visited CLS/GOAC to set up a GPS receiver to measure atmospheric water vapor (Anthes et al. 2015), contributed a fisheye lens. A CLS/GOAC researcher, Juan Carlos Antuña-Sánchez, designed and assembled it, using discarded instrument parts. He also developed the software for capturing, processing, archiving, and transmitting images (Antuña-Sánchez et al. 2015). In 2015, the instrument was improved, adding other sensors, state-of-the-art computer technology, and a polyvinyl chloride chassis. The updated camera was set up at GOA-UVa in January 2016, recording the most intense Saharan dust event observed by sun photometers at GOA-UVa (Antuña-Sánchez et al. 2016). The updated camera was set up at Camagüey in 2017 and has been registering, transmitting to GOA/UVA, and archiving locally images up to the present.
Joint work on this topic intensified in 2017 and focused on optimizing commercial sky cameras data acquisition software, developing algorithms and software for its calibration, and estimating relative radiances and the optical properties of clouds and aerosols, issues already studied at GOA-UVa (Román et al. 2017a,b). Funded by a PhD contract at GOA-UVa, the research concluded in 2022, with results reported in three articles (Antuña-Sánchez 2022). The first reports ORION software (https://goa.uva.es/orion-app/), for the semiautomatic geometric calibration of any sky camera (Antuña-Sánchez et al. 2022). The second is the optimal configuration and the processes to conduct an instrumental characterization of a sky camera (dark current, white balance, etc.), proposing a new methodology to extract sky relative radiances, from images taken in multiexposures (Antuña-Sánchez et al. 2021a). In the third, relative radiances derived from a camera are input in an inversion model to obtain aerosols properties, such as optical thickness and volume concentration (Román et al. 2022). The expertise, know-how, and tools developed are being applied for GOA-Uva’s research on clouds (González-Fernández et al. 2024a) and solar radiation (González-Fernández et al. 2024b) and by the PRESENTE project, deploying a network of all-sky cameras in Valladolid to measure cloud and aerosol optical properties at high resolution (https://goa.uva.es/proyecto-presente/). The GOA-UVa support to CLS/GOAC to develop a low-cost sky camera started a successful instrumental and scientific cooperation which is still ongoing.
e. Solar radiation.
In 2004, CLS began rescuing and recalibrating solar radiation observations with know-how provided by Ricardo Garcia Herrera at UCM and locally developed tools (Antuña et al. 2008, 2011). In 2008, a method was developed and tested, in cooperation with GOA-UVa, to determine broadband direct normal irradiance (BDNI) integrating spectral irradiances derived from sun photometer spectral digital counts. The test was conducted using BDNI from manual pyrheliometers at Camagüey and coincident sun photometer spectral digital counts. A manuscript, submitted to AMT journal, received a positive review with major concerns regarding BNDI uncertainties from manual instruments, asking for a major revision. Because of the lack of alternative datasets and work overload, it was withdrawn, but its preprint is available at AMT website (Antuña-Marrero et al. 2016a, manuscript submitted to Atmos. Meas. Tech. Discuss.).
A preliminary surface albedo climatology for Camagüey was determined using the 30-year series of solar radiation data (1981–2010). The average value of surface albedo was 0.21 ± 0.04, with a decreasing trend. Seasonal analysis showed maximum albedo values (0.22) in winter, while minimum values (0.20) occur in summer (Platero et al. 2015).
By 2020, the recovered solar radiation dataset for Camagüey amounted to 36 years (1981–2016) with 87.9% completeness and with 34 years complying with the criteria for climatological studies (WMO 2018). Then, climatological values of the global, direct, and diffuse horizontal solar radiation components and cloudiness from hourly to yearly scales were calculated. The interannual variability of yearly means was caused mainly by cloudiness. Significant decreases of the solar radiation after El Chichón (1982) and Mt. Pinatubo (1991) volcanic eruptions were found. Both eruptions had global impacts on the atmosphere and climate, also identified by CLS/GOAC in temperature records for Camagüey and Cuba (Antuña et al. 1996; Antuña 1996). The results also improved an earlier estimate of the solar energy resource in Camagüey made with modeling estimates and satellite observations (Antuña-Sánchez et al. 2021b).
f. Significance of the recorded observations and the scientific results.
The observations and scientific results from the studies described above provide a unique source of information of the optical, physical, and chemical properties of aerosols and clouds with multiple applications. At a global scale, these observations fill a gap in information for the Gulf of Mexico and the eastern Caribbean, completing their regional characterization. For Cuba, an underdeveloped country lacking fossil fuels and under difficult economic conditions, designing and operating an optimized renewable energy generation systems using solar radiation are unavoidable. Because clouds and aerosols regulate the amount of available solar radiation, the information from the observations and research results, using the climatology of solar radiation at Camagüey to improve early solar resource estimates will be at the core of the system optimization.
In addition, aerosol observations and scientific results are critical for developing a local pollution watch and alert system, by tracking the aerosol transport from its sources, Saharan dust storms in the rainy season and North American anthropogenic aerosols in the dry season. Moreover, recently released AERONET inversions with the GRASP component approach to retrieve the mass of black and brown carbon, coarse and fine aerosols both with absorbing and nonabsorbing properties (Zhang et al. 2024), provides an opportunity to include those components in the future pollution watch and alert system.
The all-sky camera’s processing algorithms implemented to determine clouds and aerosol optical properties, as well as solar irradiance relative estimates, improve and increase the cloud optical information derived from the instrument. In addition, aerosol and solar radiation information significantly increases the all-sky cameras capabilities.
The solar radiation climatology has also helped to identify and quantify volcanic impacts on solar radiation, complementing the impacts on temperature that have already identified in Camagüey and Cuba. It also supports a previous study conducted by CLS/GOAC, to alert and prepare Cuban Civil Defense authorities about the potential long decrease of solar irradiance caused by extreme events like super-volcano eruptions, near‐Earth asteroid impacts on Earth, and a nuclear war (Estevan et al. 2010).
5. Strengthening the CLS/GOAC instrumentation and cross-cutting cooperation
A solar radiation sensor angular calibration bench, designed and built by GOA-UVa, was installed in 2015. CLS/GOAC and the CMPC Radar Group prepared the calibrator’s room. The first instrument of this type in Cuba increased the CLS/GOAC services to the observational INSMET network. Inaugurated in 2016, during the Workshop for the 10th Anniversary of the CLS/GOAC and GOA-UVa Cooperation, the first calibration took place a month later.
The workshop, held at Camagüey, 27–29 January, included attendees from Spain, the United States, Europe, and Cuba (Fig. 3). Alan Robock from Rutgers University, a long-term collaborator of CLS/GOAC, attended (Antuña-Marrero et al. 2012; Anthes et al. 2015; Antuña-Marrero et al. 2017). Errico Armandillo from ESA, also a CLS-GOAC long-term supporter, was among the attendees. Brent Holben, AERONET founder and head, also attended becoming the first ever NASA scientist to visit Cuba. The results presented and discussed showed the cooperation successes. At the meeting, GOA-UVa committed a photosynthetically active radiation (PAR) sensor and Alan Robock an automatic pyranometer (Antuña-Marrero et al. 2016b). After receiving a U.S. license to export the pyranometer to Cuba, it arrived in Camagüey at the same time as the PAR. Both were set up in February 2018 and are still operative. The CMPC Radar Group, who provided engineering support to the CLS lidar (Antuña-Marrero et al. 2012), once again supported their setup. Its most qualified former staff members still support maintenance and repairs after founding the private company Laboratorio de Desarrollo Técnico (LADETEC) (https://meteoradares.wordpress.com/2023/12/21/ladetec-servicios-de-radar/).
Group photo of the attendees to the Workshop for the 10th Anniversary of the Cooperation in January 2016. Standing in the back from left to right are Joel Ernesto Díaz Venero (GOAC), Errico Armandillo (ESA), Juan R. Lachicott Suárez (GOAC), Frank García Parrado (GOAC), Juan Carlos Antuña-Sánchez (GOAC), Albeht Rodríguez Vega (GOAC), Victoria Cachorro Revilla (GOA-UVa), Terry Deshler (University of Colorado), Agustín García García (University of Extremadura, Spain), Alan Robock (Rutgers University), and Ángel de Frutos (GOA-UVa). In the front, from the left, Luis Enrique Ramos Guadalupe (Historian, Cuban Meteorological Society), Juan Carlos Antuña-Marrero (GOAC), and Abel Calle Montes (GOA-UVa).
Citation: Bulletin of the American Meteorological Society 106, 2; 10.1175/BAMS-D-23-0138.1
The goal of the CMPC radar group was to design and construct two lidar systems. The group acquired the necessary expertise and tools after the Soviet cooperation ended in 1991. They began refurbishing spare parts from dismantled Soviet instruments, studying lidar engineering, and getting training abroad (Antuña-Marrero et al. 2012) but were unable to achieve this goal because INSMET’s top priority was to protect lives and property in extreme events. The maintenance, repair, and modernization of the Cuban meteorological radar network dominated their work during all these years (Peña et al. 2000; Rodríguez et al. 2012).
The CLS/GOAC led the Latin American Lidar Network (LALINET) from 2001 to 2010. Funded by GOA-UVa, 70 peer-reviewed articles from presentations made during LALINET workshops were published, helping Latin American scientists cope with the frequent lack of funds for publications. Also, the GOA-Uva granted fellowships for two young Colombian scientists, who completed PhDs in 2009 and 2010, contributing to Latin American capacity building (Antuña-Marrero et al. 2017).
After their education, training, and experience at GOAC, Estevan and Barja left for other positions in Latin America. Estevan is heading the Huancayo Geophysical Observatory, Peru, and Barja heads a laboratory and leads aerosol and cloud research at the University of Magallanes, Chile. Most former members of CLS/GOAC still contribute to joint Cuban–Spanish research (Mogo et al. 2019; Antuña-Sánchez et al. 2021b; Rodríguez Vega et al. 2022a; Barja et al. 2023).
The GOA-UVA cooperation results also allowed the CLS/GOAC to contribute to an article and a chapter in reports of two international scientific panels: International Global Atmospheric Chemistry Project–Americas Working Group (Andrade-Flores et al. 2016) and Integrated Assessment of Short-lived Climate Pollutants in Latin America and the Caribbean (Artaxo and Raga 2016; Gallardo et al. 2018). Also, the cooperation results were the main part of Cuba’s reports to the last meeting of the Parties to the Vienna Convention for the Protection of the Ozone Layer. The Cuban report to the 10th meeting cites CLS/GOAC articles, recognizing the GOA-UVa cooperation (Peláez 2017). All Cuban articles, meeting presentations, and contributions to international panels cited in the 11th Meeting report were also results of the cooperation (Peláez 2021).
In 2016, Alan Robock introduced the CLS/GOAC to Kelly Chance, leader of NASA’s Tropospheric Emissions: Monitoring of Pollution (TEMPO) satellite mission. Estevan and Antuña-Marrero became members of its International Science Team. The contributions, so far, are to an article (Chance et al. 2019) and two talks at TEMPO online meetings (Antuña-Marrero 2016; Rodríguez Vega et al. 2022b). The CLS/GOAC envisages contributing to the TEMPO AOD validation with Camagüey AODSP and to begin using TEMPO AOD for research, pollution forecasts, and warnings.
6. Summary
A small Cuban research group, established through Soviet cooperation that was abruptly interrupted, managed to survive, develop, and evolve, thanks to scientific collaboration with Spanish and a few other international scientists. For more than a decade and a half, they cooperated in atmospheric aerosol research in a productive and mutually beneficial manner and remained active today. This represents the longest-lasting and most successful official collaboration, at least in the field of atmospheric sciences, that Cuba has sustained since the dissolution of the Soviet Union.
The cooperation conducted six joint research projects from 2008 to the present, producing datasets of aerosol optical properties and material samples unique to Cuba and the Caribbean. The results have been published in 19 articles, 16 of them peer-reviewed, and reported at 25 international conferences in 32 presentations. The cooperation also facilitated cross-cutting cooperation with other scientific teams and communities. It is an example on how to conduct cooperation between underdeveloped and developed countries.
The cooperation success has been based mainly on the excellent relationship between the researchers, especially the group leaders, as well as on mutual knowledge and respect, properly fostered through the stays and visits of the researchers. The type of cooperation we outlined above supports achieving scientific results of mutual interests, developing instrumental capabilities, and making know-how transfer, all of them rooted in the developing country local scientific team. It is the opposite of parachute science; it is rooted science.
Acknowledgments.
Cuban scientists express deep gratitude to Angel de Frutos, Victoria Cachorro, Sandra Mogo, past and present GOA-UVa members for their sustained support, know-how transfer, and confronting challenges. Thanks to Alan Robock, for leading, facilitating, and promoting international cooperation with CLS/GOAC for more than 30 years and for helping to edit this paper; Ricardo García Herrera for advising the rescue and recalibration of Cuban solar radiation datasets and with David Barriopedro backing the Caribbean aerosol climatological research; Brent Holben and Errico Armandillo for their support from 1996 to 2000, respectively; CMPC Directorate and staff (Dositeo García, Iomaris Pérez, Aramís Fonte, Julia Morejón, Teresita Hernández, Alcibiades Urquía, and Beatriz Martínez) for backing CLS/GOAC; CMPC Radar Department staff, now LADETEC company, for assisting installation, maintenance, and repair the CLS/GOAC instruments; Tomás Gutiérrez, Armando Muñoz, Pablo Reyes, Daysarih Tápanes, Celso Pazos, and INSMET Directorate for management support; and INHEM in Havana and IFU-SP for PM samples analysis. The Spanish scientists thank GOA-UVa personnel for supporting the cooperation since 2007: Santiago González, Alberto Berjón, Benjamín Torres, David Fuertes, Cristian Velasco, Agustin Martin, and Rogelio Carracedo y Patricia Martín. Cuban and Spanish scientists express their deep gratitude to Rick Anthes and two other anonymous reviewers for their work contributing to improve significantly the original manuscript.
Data availability statement.
Sun photometer data from Camagüey site are available from AERONET (Holben et al. 1998) at https://aeronet.gsfc.nasa.gov/new_web/photo_db_v3/Camaguey.html.
APPENDIX Acronyms
| AE |
Ångström exponent |
| ACTRIS |
Aerosols, Clouds, and Trace Gases Research Infrastructure |
| AMT |
Atmospheric Measurement Techniques journal |
| AOD |
Aerosol optical depth |
| BDNI |
Broadband Direct Normal Irradiance |
| CEE |
Cloud effect efficiency |
| CIAI |
Centro de Investigaciones Atmosféricas de Izaña |
| CLS |
Camagüey Lidar Station |
| CMPC |
Camagüey Provincial Meteorological Center |
| COD |
Cloud optical depth |
| CRE |
Cloud radiative effect |
| CSZA |
Cosine of zenith solar angle |
| Cu |
Cumulus clouds |
| DB |
Deep Blue |
| DRSOA |
Department of Solar Radiation and Atmospheric Optics |
| DT |
Dark Target |
| GOA-UVa |
Atmospheric Optics Group of the University of Valladolid |
| GOAC |
Grupo de Óptica Atmosférica de Camagüey |
| GRASP |
Generalized Retrieval of Aerosol and Surface Properties |
| HPMO |
The Havana Physical Meteorological Observatory |
| INHEM |
National Institute of Hygiene, Epidemiology, and Microbiology |
| INSMET |
Cuban Institute of Meteorology |
| LADETEC |
Laboratorio de Desarrollo Técnico |
| LALINET |
Latin American Lidar Network |
| NASA |
National Aeronautics and Space Administration |
| ORION |
All-sky camera geometry calibration from star positions |
| PM |
Particulate matter |
| PM1 |
Particulate matter that is smaller than 1 μm in diameter |
| PAR |
Photosynthetically active radiation |
| RIMA |
Red Ibérica de Medida fotométrica de Aerosoles |
| ROCB |
Royal Observatory of the College Belen College |
| Sc |
Stratocumulus clouds |
| Sc-Cu |
Mixed stratocumulus–cumulus clouds |
| TEMPO |
Tropospheric Emissions: Monitoring of Pollution |
| UBI |
Universidade da Beira Interior |
| UCM |
Universidad Complutense de Madrid |
References
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