Person:
Carrillo Rojas, Galo José

Birth Date

1978-04-28

ORCID

0000-0003-4410-6926

Scopus Author ID

56117784400

Afiliación

Universidad de Cuenca, Facultad de Ciencias Químicas, Cuenca, Ecuador
Universidad de Cuenca, Departamento de Recursos Hídricos y Ciencias Ambientales, Cuenca, Ecuador

País

Ecuador

Organizational Units

Organizational Unit

Facultad de Ciencias Químicas

Fundada en 1955 como la Escuela de Química Industrial, la facultad ha sido un pilar fundamental en la formación de profesionales altamente capacitados, comprometidos con el desarrollo de la ciencia, la educación y el bienestar social. La Facultad de Ciencias Químicas pone a consideración su trabajo académico, investigativo y de vinculación con la sociedad, desarrollado a través de la práctica de una docencia de calidad, investigación e innovación en su área de estudio. Desde su oficio de conocimiento se permite contribuir a la sociedad con cuatro carreras: Bioquímica y Farmacia, Ingeniería Química, Ingeniería Ambiental e Ingeniería Industrial. Su carta de presentación en la Academia, la coloca como una dependencia dinámica, donde confluye la solidez de una trayectoria de más de sesenta años. Aquí se trabaja en una continua formación de pregrado y posgrado de la más alta calidad, mediante la mejora continua con la innovación y a la vanguardia de las ciencias químicas.

Job Title

Profesor (T)

Last Name

Carrillo Rojas

First Name

Galo José

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Now showing 1 - 10 of 17

Evaluation of the Penman-Monteith (FAO 56 PM) Method for Calculating Reference Evapotranspiration Using Limited Data
(INTERNATIONAL MOUNTAIN SOCIETY, 2015-08-01) Córdova Mora, Mario Andrés; Carrillo Rojas, Galo José; Célleri Alvear, Rolando Enrique; Crespo Sánchez, Patricio Javier
(Figure Presented) Reference evapotranspiration (ETo) is often calculated using the Penman-Monteith (FAO 56 PM; Allen et al 1998) method, which requires data on temperature, relative humidity, wind speed, and solar radiation. But in high-mountain environments, such as the Andean páramo, meteorological monitoring is limited and high-quality data are scarce. Therefore, the FAO 56 PM equation can be applied only through the use of an alternative method suggested by the same authors that substitutes estimates for missing data. This study evaluated whether the FAO 56 PM method for estimating missing data can be effectively used for páramo landscapes in the high Andes of southern Ecuador. Our investigation was based on data from 2 automatic weather stations at elevations of 3780 m and 3979 m. We found that using estimated wind speed data has no major effect on calculated ETo but that if solar radiation data are estimated, ETo calculations may be erroneous by as much as 24%; if relative humidity data are estimated, the error may be as high as 14%; and if all data except temperature are estimated, errors higher than 30% may result. Our study demonstrates the importance of using high-quality meteorological data for calculating ETo in the wet páramo landscapes of southern Ecuador.
Dynamic mapping of evapotranspiration using an energy balance-based model over an andean páramo catchment of southern ecuador
(MDPI AG, 2016-01-01) Carrillo Rojas, Galo José; Célleri Alvear, Rolando Enrique; Córdova Mora, Mario Andrés
Understanding of evapotranspiration (ET) processes over Andean mountain environments is crucial, particularly due to the importance of these regions to deliver water-related ecosystem services. In this context, the detection of spatio-temporal changes in ET remains poorly investigated for specific Andean ecosystems, like the páramo. To overcome this lack of knowledge, we implemented the energy-balance model METRIC with Landsat 7 ETM+ and MODIS-Terra imagery for a páramo catchment. The implementation contemplated adjustments for complex terrain in order to obtain daily, monthly and annual ET maps (between 2013 and 2014). In addition, we compared our results to the global ET product MOD16. Finally, a rigorous validation of the outputs was conducted with residual ET from the water balance. ET retrievals from METRIC (Landsat-based) showed good agreement with the validation-related ET at monthly and annual steps (mean bias error <8 mm. month-1 and annual deviation <17%). However, METRIC (MODIS-based) outputs and the MOD16 product were revealed to be unsuitable for our study due to the low spatial resolution. At last, the plausibility of METRIC to obtain spatial ET retrievals using higher resolution satellite data is demonstrated, which constitutes the first contribution to the understanding of spatially-explicit ET over an alpine catchment in the neo-tropical Andes.
Near-surface air temperature lapse rate over complex terrain in the Southern Ecuadorian Andes: Implications for temperature mapping
(Institute of arctic and alpine research, 2016-11-01) Córdova Mora, Mario Andrés; Abril Orellana, Olmedo Andrés; Carrillo Rojas, Galo José; Célleri Alvear, Rolando Enrique; Orellana-Alvear, J
Near-surface air temperature variation with altitude (Tlr) is important for several applications including hydrology, ecology, climate, and biodiversity. To calculate Tlr accurately, a dense monitoring network over an altitudinal gradient is needed. Typically, meteorological monitoring in mountain regions is scarce and not adequate to calculate Tlr correctly. To overcome this problem in our region, we monitored temperature over a gradient ranging 2600-4200 m a.s.l. during an 18 month period. Using these data, we calculated Tlr for the first time at this altitude in the Andes and tested the impact of using the standard Tlr values instead of the observed ones to map temperature by means of the MTCLIM model. We found that annual lapse rate values (6.9 °C km-1 for Tmean, 5.5 °C km-1 for Tmin, and 8.8 °C km-1 for Tmax) differ significantly from the MTCLIM default values and that temperature maps improved vastly when measured Tlr was entered, especially for Tmax and Tmin. Our results may be representative of the broader area, as Tlr in our study period is not affected by microclimatic conditions generated by differences in topography and land cover between our monitoring sites; moreover, observed temperature during our study period was found to be representative of the longer-term annual climatology of the region.
Improving reference evapotranspiration (ETo) calculation under limited data conditions in the high Tropical Andes
(2022) Carrillo Rojas, Galo José; Córdova Mora, Mario Andrés; Vásquez Ojeda, Cristina Alejandra; Célleri Alvear, Rolando Enrique
The computation of the reference crop evapotranspiration (ETo) using the FAO56 Penman-Monteith equation (PM-ETo) requires data on maximum and minimum air temperatures (Tmax, Tmin), relative humidity (RH), solar radiation (Rs), and wind speed (u2). However, the records of meteorological variables are often incomplete or of poor quality. Frequently, in the mountain areas such as those of the Andes, environmental sensors are subject to harsh conditions, due to the diurnal/nocturnal climatic variability causing challenging conditions for meteorological monitoring, which leads to data loss. For high-elevation landscapes like the Andes, the missing variables of vapor pressure deficit and solar radiation cause a high impact on PM-ETo calculation. To assess these limitations, several methods relying on maximum and minimum temperature to estimate the missing variables have been considered in the present investigation. Based on data from three automatic weather stations in the high Tropical Andes (humid páramo, 3298 – 3955 m a.s.l.), we found that the calibration and validation of methods were essential to estimate Rs. Using the (De Jong and Stewart, 1993) (Rs-DS) method we retrieved the highest performance, a RMSE between 2.89 and 3.81 MJ m−2 day−1. Moreover, In the absence of RH observations, replacing the dew point temperature (Tdew) by Tmin was a reliable alternative, when apply the method of (Allen et al., 1998) (VPD-FAO) which showed the highest performance with RMSE between 0.08 and 0.12 kPa. These results yielded highly accurate PM-ETo estimates, with RMSE between 0.29 and 0.34 mm day−1 and RMSE between 0.12 and 0.18 mm day−1, respectively. As expected, when both variables were missing, the ETo calculation increased its error, with an RMSE between 0.32 and 0.42 mm day−1. A proper estimation of ETo in the Andean páramo contributes to improved water productivity for domestic and industrial uses, irrigated agriculture, and hydropower.
The breathing of the andean highlands: net ecosystem exchange and evapotranspiration over the páramo of southern Ecuador
(2019) Carrillo Rojas, Galo José; Silva, Brenner; Rollenbeck, Rütger; Célleri Alvear, Rolando Enrique; Bendix, Jorg
Atmospheric carbon (CO 2) exchange, evapotranspiration (ET) processes, and their interactions with climatic drivers across tropical alpine grasslands are poorly understood. This lack of understanding is particularly evident for the páramo, the highest vegetated frontier in the northern Andes, the main source of water for inter-Andean cities, and a large carbon storage area. Studies of CO 2 and ET fluxes via the standard Eddy Covariance (EC) technique have never been applied to this region, limiting the understanding of diurnal / nocturnal exchanges and budget estimations. In this paper, we report the first EC analysis conducted on the Andean páramo (3765 m a.s.l.); this analysis measured CO 2, ET, and micrometeorological variables over two years (2016–2018) to understand their interactions with climatic / biophysical controls. The páramo was found to be a source of CO 2 and exhibited a net positive exchange …
Impact of electrical energy efficiency programs, case study: food processing companies in Cuenca, Ecuador
(2014-04-01) Carrillo Rojas, Galo José; Andrade Rodas, Juan Manuel; Barragán Escandón, Edgar Antonio; Astudillo Alemán, Ana Lucía
This exploratory study illustrates the effects of the application of electrical energy efficiency programs in 7 food processing companies in Cuenca, Ecuador. The research encompassed phases of diagnosis, intervention and evaluation. A comparative analysis between the companies was conducted: energy consumption versus product volume, energy-quality analysis, relation between compliance/specific energy consumption, and the impact on CO2 emissions. Results revealed that the acceptance to the recommendations of savings is biased by the level of investments and the willing/proneness of the administration. The study showed that interventions had a partial effect on the reduction of the specific energy consumption in 4 companies. In addition, it has obtained a positive effect on the power factor correction in one company and an improvement on the load balance in 5. The research showed the existence of a significant reduction of emissions post-intervention, highlighting the effectiveness of the programs. © The authors; licensee Universidad Nacional de Colombia.
Evaporation dynamics and partitioning in Andean tussock grasslands
(Ed, 2022) Célleri Alvear, Rolando Enrique; Ochoa Sánchez, Ana Elizabeth; Crespo Sánchez, Patricio Javier; Carrillo Rojas, Galo José; Sucozhañay Calle, Adrián Esteban; Marín Molina, Franklin Geovanny; Ochoa Sánchez, Ana Elizabeth
The paramo biome, located above 3300 m a.s.l. and covered mainly by tussock grasslands, provides ecosystem services for Andean cities, especially water resources used for drinking water, agriculture, hydropower generation and sustaining aquatic ecosystems. Even though research about the main components of the water cycle has increased substantially in the last decade, evaporation has remained unknown. In this study, we quantified for the first time daily, monthly and annual evaporation, its components (i.e. interception and transpiration) at event scale and its climatic drivers at a representative páramo catchment in Southern Ecuador (Figure 1). We used the eddy-covariance method to quantify evaporation. We additionally compared those measurements with lysimeters, water balance, energy balance, hydrological models (HBV-light and PDM) and the calibration of the Penman-Monteith equation in order to find easier and cheaper alternatives for estimating evaporation at the páramo
Altitudinal and temporal evapotranspiration dynamics via remote sensing and vegetation index-based modelling over a scarce-monitored, high-altitudinal Andean páramo ecosystem of Southern Ecuador
(2019) Ramón Reinozo, Mayra; Ballari, Daniela Elisabet; Cabrera Cabrera, Juan Geovanny; Crespo Sánchez, Patricio Javier; Carrillo Rojas, Galo José
In the tropical Andes, the paramo ecosystem is known as water towers and the main water supplier for the cities of the Andean region. Nevertheless, considering that evapotranspiration (ET) is the major water loss and the lack of in situ evapotranspiration measurements in high altitudinal paramo ecosystems, ET dynamics on the hydrological regulation remains largely unexplored. Therefore, to close this gap, we focused on a remote sensing approach. This study addressed the altitudinal and temporal dynamics of actual evapotranspiration using a crop coefficient based on a Vegetation Index (VI) model. Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI) and Soil-Adjusted Vegetation Index (SAVI) retrieved from Landsat imagery were evaluated. Four remote sensing images and ground-level meteorological data for a 10-month period were used to create ET maps from each VI. A cubic spline interpolation was used to obtain daily ET time series between two satellite overpass dates. Aggregated monthly values were used to validate against ET calculated from water balance. Results revealed that EVI-based ET outperformed the other VI-based ET. The results showed 30% of subestimation (Pbias%) in relation to the water balance. For upgraded results, an extended satellite images time series and a fine calibration are needed. Regarding the altitudinal variability, ET exhibited a strong dependence on land cover characteristics. Our work provides a plausible method to estimate ET in paramo ecosystems in the absence of ET measurements and with a scarcity of clear sky images, further evaluation is necessary to improve ET estimations using remote sensing in the future.
Turbulent energy and carbon fluxes in an andean montane forest—energy balance and heat storage
(2024) Carrillo Rojas, Galo José
High mountain rainforests are vital in the global energy and carbon cycle. Understanding the exchange of energy and carbon plays an important role in reflecting responses to climate change. In this study, an eddy covariance (EC) measurement system installed in the high Andean Mountains of southern Ecuador was used. As EC measurements are affected by heterogeneous topography and the vegetation height, the main objective was to estimate the effect of the sloped terrain and the forest on the turbulent energy and carbon fluxes considering the energy balance closure (EBC) and the heat storage. The results showed that the performance of the EBC was generally good and estimated it to be 79.5%. This could be improved when the heat storage effect was considered. Based on the variability of the residuals in the diel, modifications in the imbalances were highlighted. Particularly, during daytime, the residuals were largest (56.9 W/m2 on average), with a clear overestimation. At nighttime, mean imbalances were rather weak (6.5 W/m2) and mostly positive while strongest underestimations developed in the transition period to morning hours (down to −100 W/m2). With respect to the Monin–Obukhov stability parameter ((z − d)/L) and the friction velocity (u*), it was revealed that the largest overestimations evolved in weak unstable and very stable conditions associated with large u* values. In contrast, underestimation was related to very unstable conditions. The estimated carbon fluxes were independently modelled with a non-linear regression using a light-response relationship and reached a good performance value (R2 = 0.51). All fluxes were additionally examined in the annual course to estimate whether both the energy and carbon fluxes resembled the microclimatological conditions of the study site. This unique study demonstrated that EC measurements provide valuable insights into land-surface–atmosphere interactions and contribute to our understanding of energy and carbon exchanges. Moreover, the flux data provide an important basis to validate coupled atmosphere ecosystem models.
Overcast sky condition prevails on and influences the biometeorology of the tropical Andean Páramos
(2023) Montenegro Díaz, Paola Fernanda; Célleri Alvear, Rolando Enrique; Carrillo Rojas, Galo José
Clouds play a major role in modulating the biometeorological processes. We studied the influence of cloudiness on four biometeorological variables: daily air temperature (Tair), relative humidity (RH), reference evapotranspiration (ETr), and photosynthetic active radiation (PAR), recorded at four sites of Andean Páramos in southern Ecuador during 2.5 to 5.5 years. First, we quantified both the cloud cover percentage (Cloud%) creating cloud masks over the visible bands of Landsat 7 images and the sky condition (KT) using the records of solar and extraterrestrial radiation. Second, we estimated KT from Cloud%. Finally, we quantified Tair, RH, ETr, and PAR under clear, cloudy, and overcast KT and their dependence on KT. The average Cloud% ranged between 65%–76%, and KT corroborated the prevailing overcast sky (between 55% and 72.5% of the days) over the páramos. The proposed model performed well in the sites of calibration (R2 = 0.80; MBE = 0.00; RMSE = 0.05) and validation (R2 = 0.74; MBE = -0.07; RMSE = 0.11). The overcast sky diminished Tair (≤ 10oC), ETr (≤ 1.6 mm day-1), and PAR (4 MJ m-2 day-1) and increased RH (≥ 88%), while the variables showed the opposite behavior during the uncommon clear sky (≤ 5.5% of the days). Thus, mostly the dynamic of RH (R2 ≥ 0.62), ETr (R ≥ 0.85), and PAR (R2 ≥ 0.77) depended on KT. Hence, the prevailing overcast sky influenced the biometeorology of the páramos.