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Measurements of methane concentrations were made at the Chacaltaya GAW station (16.3ºS, 68.1ºW, 5240m a.s.l.) in the Andean Cordillera from 2015 to date. During this period two high-precision Picarro-CRDS analyzers were used at the station, regularly calibrated with internationally certified gases (WMO X2004A) via the LSCE primary scale. The site has a privileged location not only due to its altitude but also because air masses arriving from the near Altiplano (3 800 m a.s.l.), the Amazon (so-called low-lands), the Pacific Ocean, and the nearby metropolitan area of La Paz/El Alto (~2 million of inhabitants) can be sampled there. The complex topography of the region represents a challenge for deconvoluting the origin of the air masses and therefore to understanding the sources and/or processes associated with the measurements made at Chacaltaya. Here we show some results based on re-analysis data as well as on high and medium - resolution back trajectories in order to identify the influence of different regions on the station. In addition, satellite products and satellite-derived databases, from TROPOMI and GFED4.1s and WAD2M are used to characterize and interpret daily, seasonal and interannual behavior of the methane concentrations observed in Chacaltaya. The influence of the local atmospheric planetary boundary layer is clearly seen in the measurements, especially in the late morning, but collocated measurements of other atmospheric components such as carbon monoxide or equivalent black carbon have proven that identifying free-tropospheric air masses is not an easy task. The contributions of the largest human conglomerate of the region are also discussed in this context.

Ten years of almost continuous observations at the highest Global Atmosphere Watch Regional station in the world are presented here. The Chacaltaya observatory (5240 m asl, 16.3ºS, 68.1ºW) was set up in December 2011. It is currently the only operational station characterizing optical and chemical properties of climate-relevant aerosol and gases in Bolivia and in a radius of about 1500 kilometers from the station. The observations show a clear influence of the well-marked dry and wet meteorological seasons. In addition, the impact on the Andean mountains of long and mid-range transport of biomass burning products from the lowlands is clearly recorded in different parameters measured at the station. Furthermore, the nearby presence of the largest metropolitan area in the region (~1.8 million inhabitants) is observed almost on a daily basis, and therefore different campaigns were carried out to characterize the area and its influence on our measurements. Specific results from these campaigns are discussed elsewhere. Finally, the topographic complexity represents an important challenge for modeling efforts in order to understand sources and sinks (and associated processes) of the observed parameters, requiring not only high spatial resolution and the correct choice of model options, but a novel way of interpreting these results. The decade of collaboration of an international consortium made it possible to keep the station running successfully. The challenge is now to preserve its functioning for the coming decades in a region with historically few high-quality observations while disrupting environmental and socio-economic changes take place.

El objetivo del estudio fue determinar la relación entre la actividad física, el estrés laboral y el estado nutricional con el riesgo cardiovascular en una muestra de 300 policías de una Unidad Operativa, Lima 2020. La investigación fue de nivel descriptivo correlacional, enfoque cuantitativo, tipo básico, y diseño no experimental. Se aplicó los cuestionarios de actividad física (GPAQ), y de estrés laboral de McCreary & Thompson, el estado nutricional se evaluó con el índice de masa corporal (IMC) y el riesgo cardiovascular con el perímetro abdominal (PAB). Se analizó con el programa estadístico SPSS versión 25, empleando tablas de frecuencia y la prueba de correlación de Spearman. Los resultados mostraron que el 86% realizaba alto nivel de actividad física; el 69,67% no mostró estrés laboral el 59,33% sobrepeso, el 28,67% obesidad; el 40.67% mostró riesgo cardiovascular incrementado y el 22,67% alto riesgo. Existe relación entre el estado nutricional y el riesgo cardiovascular (Rho=0,63; p=0.033), existe relación entre el estrés laboral y riesgo cardiovascular (Rho=0,156; p=0,007). No existe relación significativa entre la actividad física, estrés laboral con el riesgo cardiovascular (Rho=0,92; p=0,058), (Rho=0,218; p=0,055). La actividad física en el trabajo no se relaciona con el riesgo cardiovascular (Rho=0.022, p>0,05). Se concluye que existe relación no significativa entre la actividad física, el estrés laboral y el estado nutricional con el riesgo cardiovascular. The objective of the study was to determine the relationship between physical activity, work stress and nutritional status with cardiovascular risk in a sample of 300 police officers from an Operative Unit, Lima 2020. The research was descriptive correlational, quantitative approach, type basic, and non-experimental design. The physical activity questionnaires (GPAQ) and the McCreary & Thompson work stress questionnaire were applied, the nutritional status was evaluated with the body mass index (BMI) and cardiovascular risk with the abdominal perimeter (PAB). It was analyzed with the statistical program SPSS version 25, using frequency tables and Spearman's correlation test. The results showed that 86% performed a high level of physical activity; 69.67% did not show police work stress; 59.33% overweight, 28.67% obesity; 40.67% showed increased cardiovascular risk and 22.67% high risk. There is a relationship between nutritional status and cardiovascular risk (Rho=0.63; p=0.033), there is a relationship between organizational work stress and cardiovascular risk (Rho=0.156; p=0.007). There is no significant relationship between physical activity, work stress and cardiovascular risk (Rho=0.92; p=0.058), (Rho=0.218; p=0.055). Physical activity at work is not related to cardiovascular risk (Rho=0.022, p>0.05). concluded that there is a non-significant relationship between physical activity, work stress and nutritional status with cardiovascular risk.

Amazonian deforestation has accelerated during the last decade, threatening an ecosystem where almost one third of the regional rainfall is transpired by the local rainforest. Due to the precipitation recycling, the southwestern Amazon, including the Amazon-Andes transition region, is particularly sensitive to forest loss. This study evaluates the impacts of Amazonian deforestation in the hydro-climatic connectivity between the Amazon and the eastern tropical Andes during the austral summer (December-January-February) in terms of hydrological and energetic balances. Using 10-year high-resolution simulations (2001–2011) with the Weather Research and Forecasting Model, we analyze control and deforestation scenario simulations. Regionally, deforestation leads to a reduction in the surface net radiation, evaporation, moisture convergence and precipitation (~ 20%) over the entire Amazon basin. In addition, during this season, deforestation increases the atmospheric subsidence over the southern Amazon and weakens the regional Hadley cell. Atmospheric stability increases over the western Amazon and the tropical Andes inhibiting convection in these areas. Consequently, major deforestation impacts are observed over the hydro-climate of the Amazon-Andes transition region. At local scale, nighttime precipitation decreases in Bolivian valleys (~ 20–30%) due to a strong reduction in the humidity transport from the Amazon plains toward Andes linked to the South American low-level jet. Over these valleys, a weakening of the daytime upslope winds is caused by local deforestation, which reduces the turbulent fluxes at lowlands. These alterations in rainfall and atmospheric circulation could impact the rich Andean ecosystems and its tropical glaciers.

In situ climatological observations are essential for studies related to climate trends and extreme events. However, in many regions of the globe, observational records are affected by a large number of data quality issues. Assessing and controlling the quality of such datasets is an important, often overlooked aspect of climate research. Besides analysing the measurement data, metadata are important for a comprehensive data quality assessment. However, metadata are often missing, but may partly be reconstructed by suitable actions such as station inspections. This study identifies and attributes the most important common data quality issues in Bolivian and Peruvian temperature and precipitation datasets. The same or similar errors are found in many other predominantly manned station networks worldwide. A large fraction of these issues can be traced back to measurement errors by the observers. Therefore, the most effective way to prevent errors is to strengthen the training of observers and to establish a near real-time quality control (QC) procedure. Many common data quality issues are hardly detected by usual QC approaches. Data visualization, however, is an effective tool to identify and attribute those issues, and therefore enables data users to potentially correct errors and to decide which purposes are not affected by specific problems. The resulting increase in usable station records is particularly important in areas where station networks are sparse. In such networks, adequate selection and treatment of time series based on a comprehensive QC procedure may contribute to improving data homogeneity more than statistical data homogenization methods.

Systematic data quality issues may occur at various stages of the data generation process. They may affect large fractions of observational datasets and remain largely undetected with standard data quality control. This study investigates the effects of such undetected data quality issues on the results of climatological analyses. For this purpose, we quality controlled daily observations of manned weather stations from the Central Andean area with a standard and an enhanced approach. The climate variables analysed are minimum and maximum temperature, and precipitation. About 40 % of the observations are inappropriate for the calculation of monthly temperature means and precipitation sums due to data quality issues. These quality problems undetected with the standard quality control method strongly affect climatological analyses, since they reduce the correlation coefficients of station pairs, deteriorate the performance of data homogenization methods, increase the spread of individual station trends, and significantly bias regional temperature trends. Our findings indicate that undetected data quality issues are included in important and frequently used observational datasets, and hence may affect a high number of climatological studies. It is of utmost importance to apply comprehensive and adequate data quality control approaches on manned weather station records in order to avoid biased results and large uncertainties.

En la presente investigación se caracterizó y evaluó un tratamiento a las aguas superficiales provenientes del Rio Chili, de la ciudad de Arequipa – Perú, compuesta principalmente por aguas residuales domésticas, efluentes de granjas, camales, desechos industriales, desechos agrícolas, conteniendo como fuente de contaminación a los metales pesados como el cromo, plomo, arsénico entre otros, así también se encontró coliformes fecales, totales, virus, bacterias, aceites y grasas, alto contenido de sólidos suspendidos, sólidos disueltos y se investigó comparativamente su porcentaje de remoción con pectina obtenidos de diferentes frutos a partir de la cáscara de naranja, limón y de mandarina. Las muestras fueron monitoreadas directamente del puente de ingreso al distrito de Congata – Tiabaya, se aplicó un tratamiento de aguas por un proceso de coagulación, floculación usando un bioadsorbente natural monitoreado en un dispositivo de pruebas de jarras. El pre-tratamiento del material biosorbente, pectina obtenida a partir de la cáscara de naranja, limón y mandarina, se llevó a cabo mediante la selección de la cáscara de estos frutos, para posteriormente ser lavadas, secadas, trituradas, y desmetóxiladas con hidróxido de sodio (NaOH), y luego ser reticulada con una solución de cloruro de calcio (CaCl2), a un pH 5 y en agitación constante, obteniendo un tamaño de 180-250 µm. obteniendo así las siguientes características con relación a la pectina de naranja el pH fue de 6,25; humedad 13,14% contenido de cenizas de 9,73%; fibra 22,71%; pectina de limón el pH fue de 6,55; humedad 12,57%; contenido de cenizas 10,51%; fibra 27,43% y pectina de mandarina el pH fue de 5,55; humedad 12,76%, cenizas 9,39% y fibra de 26,11%. De acuerdo con el bioadsorbente obtenido en el presente trabajo de investigación los resultados obtenidos fueron de acuerdo a las pruebas mostradas en el capítulo (III), las pruebas aplicadas al agua superficial de Río Chili al trabajar con pectina de naranja se obtuvo un porcentaje de remoción de 43,13% de arsénico; 17,65% de cromo; con respecto a la pectina de limón logró remover 40,89% de arsénico; 11,76% de cromo y al trabajar con pectina de mandarina logró remover 43,64% de arsénico; 71,95% de plomo. Logrando así obtener un resultado eficiente con respecto a la pectina de mandarina; con relación a la concentración de plomo logró remover 71,95%; así también con respecto a la concentración de arsénico logró un mayor porcentaje de remoción de 43,64% en comparación con la pectina de naranja y limón que solo obtuvieron 43,13% y 40,89% respectivamente. Tesis