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This study presents a new zenith looking narrow-band radiometer based system (ZEN), conceived for dust aerosol optical depth (AOD) monitoring. Our results suggest that ZEN is a suitable system to fill the current observational gaps and to complement observations performed by sun-photometer networks in order to improve mineral dust monitoring in remote locations. AERONET sun photometers at Izaña have been calibrated within the AERONET Europe TNA, supported by the European Community-Research Infrastructure Action under the FP7 15 ACTRIS grant agreement no. 262254.

This work presents an observational data set of upper tropospheric CH4 and N2O products retrieved from the thermal emission spectra measured by the satellite sensor IASI (Infrared Atmospheric Sounding Interferometer), aboard the EUMETSAT satellites MetOp. The quality of the products is documented by an theoretical error estimation and by an extensive comparison study to HIPPO aircraft in-situ data. The research leading to these results has received funding from the European Research Council under FP7/(2007-2013)/ERC Grant agreement n◦256961 (project MUSICA), from the Ministerio de Economía y Competitividad from Spain trough the project CGL2012-37505 (project NOVIA), from the Ministerio de Educación, Cultura y Deporte (Programa "José Castillejo", CAS14/00282), and from EUMETSAT under its Fellowship Programme (project VALIASI).

A 1-year intercomparison of classical and modern radiation and sunshine duration instruments has been performed at Izaña Atmospheric Observatory. We compare global solar radiation (GSR) records measured with a Kipp & Zonen CM-21 pyranometer, taken in the framework of the Baseline Surface Radiation Network, with those measured with a multifilter rotating shadowband radiometer and a bimetallic pyranometer, and with GSR estimated from sunshine duration performed with a CS sunshine recorder.

Comunicación presentada en: TECO-2016 (Technical Conference on Meteorological and Environmental Instruments and Methods of Observation) celebrada en Madrid, del 27 al 30 de septiembre de 2016. This work has been developed within the framework of the activities of the World Meteorological Organization (WMO) Commission for Instruments and Methods of Observations (CIMO) Izaña Testbed for Aerosols and Water Vapor Remote Sensing Instruments. AERONET sun photometers at Izaña have been calibrated within the AERONET Europe TNA, supported by the European Community ‐ Research Infrastructure Action under the FP7 ACTRIS grant agreement no. 262254.

This study presents a new zenith looking narrow-band radiometer based system (ZEN), conceived for dust aerosol optical depth (AOD) monitoring. Our results suggest that ZEN is a suitable system to fill the current observational gaps and to complement observations performed by sun-photometer networks in order to improve mineral dust monitoring in remote locations. AERONET sun photometers at Izaña have been calibrated within the AERONET Europe TNA, supported by the European Community-Research Infrastructure Action under the FP7 15 ACTRIS grant agreement no. 262254.

This paper presents the reconstruction of a 73-year time series of the aerosol optical depth (AOD) at 500 nm at the subtropical high-mountain Izaña Atmospheric Observatory (IZO) located in Tenerife (Canary Islands, Spain). For this purpose, we have combined AOD estimates from artificial neural networks (ANNs) from 1941 to 2001 and AOD measurements directly obtained with a Precision Filter Radiometer (PFR) between 2003 and 2013. The analysis is limited to summer months (July–August–September), when the largest aerosol load is observed at IZO (Saharan mineral dust particles). The ANN AOD time series has been comprehensively validated against coincident AOD measurements performed with a solar spectrometer Mark-I (1984–2009) and AERONET (AErosol RObotic NETwork) CIMEL photometers (2004–2009) at IZO, obtaining a rather good agreement on a daily basis: Pearson coefficient, R, of 0.97 between AERONET and ANN AOD, and 0.93 between Mark-I and ANN AOD estimates. In addition, we have analysed the long-term consistency between ANN AOD time series and long-term meteorological records identifying Saharan mineral dust events at IZO (synoptical observations and local wind records). Both analyses provide consistent results, with correlations > 85 %. Therefore, we can conclude that the reconstructed AOD time series captures well the AOD variations and dust-laden Saharan air mass outbreaks on short-term and long-term timescales and, thus, it is suitable to be used in climate analysis. The AERONET Cimel sun photometer at Izaña has been calibrated by AERONET-EUROPE Calibration Service, financed by the Aerosol Cloud and TRace gas InfraStructure (ACTRIS) European Research Infrastructure Action (FP7/2007-2013 no. 262254). Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) and from the “Fondo Europeo de Desarrollo Regional” (FEDER) for project CGL2012-33576 is gratefully acknowledged.

Póster elaborado para el International Symposium CLIMA-ES 2015 celebrado en Tortosa, Spain, los días 11-13 March 2015. Solar radiation controls the energy radiative balance in the Earth and, thus, our weather and climate. For this reason, its study has been one of the main objectives of the research community during the last decades. Recently, the focus is on evaluating long-term trends of solar radiation reaching the Earth‟s surface as well as on identifying the variability driven by the climate change. Observational evidences of changes on global solar radiation (GSR) trends have already been reported at a global scale. In this context, the goal of this work is to perform a reconstruction of the GSR time series between 1933 and 2013 at the subtropical high-mountain Izaña Atmospheric Observatory (IZA) located in Tenerife (28.3°N, 16.5°W, 2373 m a.s.l., Spain). For this purpose, we combine GSR estimates from sunshine duration (SD) data using the Ångström–Prescott method over the 1933/1991 period, and GSR observations directly performed by different pyranometers between 1992 and 2013. This work was developed under the Specific Agreement of Collaboration between the Meteorological State Agency (AEMET) of Spain and the University of Valladolid. Financial supports from the Spanish Ministry of Economy and Competitiveness (MINECO) and from the “Fondo Europeo de Desarrollo Regional” (FEDER) for projects CGL2011-23413, CGL2012-33576 and CGL2012-37505 are gratefully acknowledged.

Resumen de la comunicación oral presentada en: 1st Iberian Meeting on Aerosol Science and Technology – RICTA 2013, celebrado del 1 al 3 de julio de 2013 en Évora, Portugal.

Comunicación presentada en: 2012 European Aerosol Conference (EAC-2012), B-WG01S2P30, celebrada del 2 al 7 de septiembre de 2012 en Granada. Financial support from the Spanish MICINN under projects with ref. CGL2009-09740, CGL2011-23413, CGL2010-09480-E and CGL2011-13085-E is gratefully acknowledged.

Comunicación presentada en: 2012 European Aerosol Conference (EAC-2012), B-WG01S2P30, celebrada del 2 al 7 de septiembre de 2012 en Granada. Financial supports from the Spanish MICIIN (projects of ref. CGL2008-05939-CO3-01/CLI, CGL 2009-09740, and "Acción Complementaria" CGL2010-09480-E and CGL2011-13085-E), and from the Environmental Council of the CyL Regional Government (Consejería de Medio Ambiente, Junta de Castilla y León) are gratefully acknowledged.

Póster presentado en: Twelfth BSRN Scientific Review and Workshop, celebrado del 1 al 3 de agosto de 2012 en Potsdam, Alemania. Financial supports from the Spanish MICIIN for projects CGL2009-09740, CGL2011-23413 and CGL2010-09480E, CGL2011-13085-E are gratefully acknowledged.

Knowledge of the diurnal cycle of precipitable water vapor (PWV) is very limited owing to the lack of data with sufficient temporal resolution. Currently, GPS receivers have proven to be a suitable technique to determine PWV diurnal variations. In this study, the annual and seasonal diurnal cycles of PWV have been obtained from GPS data for 10 locations over Spain. The minimum value of PWV is reached approximately at the same time at all the stations, ∼0430–0530 UTC, whereas the maximum is reached in the second half of the day, but with a larger dispersion of its occurrence between stations. The annual sub-daily variability ranges from 0.41 to 1.35 mm (3–7%). The highest values are recorded at the stations on the Mediterranean coast, with a doubling of the values of the stations on the Atlantic coast or inland. The winter cycle is quite similar at all locations, whereas in summer local effects are felt strongly, making the diurnal cycle quite different between stations. The PWV mean diurnal cycle is strongest in summer and weakest in spring, with a sub-daily variability of 1.34 and 0.66 mm respectively. Harmonic analysis shows that the first two harmonics can explain 97% of the variance. The diurnal (24 h) harmonic explains 85% of the variance, has mean amplitude of 0.40 mm, and the peak time is from early afternoon to evening. The semi-diurnal (12 h) harmonic is weaker, with an amplitude of 0.13 mm, and peak time between 0400 and 1000 UTC. The diurnal cycle of temperature alone would be a proxy for PWV cycle during the night, but not during the daytime. The breeze regime is the main factor responsible for the phase lag between PWV and temperature cycles during daytime. No clear correlation between the daily cycle of precipitation and PWV has been found.

Póster elaborado para el 13th BSRN Scientific Review and Workshop celebrado en Bologna (Italy) en September 9-12, 2014. The Izaña Atmospheric Observatory (IZA) is part of the Global Atmospheric Watch (GAW) programme and is managed by the Izaña Atmospheric Research Center (IARC) belonging to the Meteorological State Agency of Spain (AEMET). It is located in the Tenerife Island (The Canary Islands; 28º18’ N, 16º29’ W, 2.367 m a.s.l) above a quasi-permanent inversion layer with excellent conditions for in situ and column measurements of trace gases and aerosols under “free troposphere” conditions. The environmental conditions (stable total column ozone, very low precipitable water vapour and low aerosols content) and the high frequency of clean and pristine skies make IZA an optimal site for calibration and validation activities. In fact, IZA is a WMO-CIMO Testbed for Aerosols and Water Vapor Remote Sensing Instruments and the WMO Regional Brewer Calibration Center for Europe (RBCC-E) . The radiation site in Izaña is part of BSRN since March 2009. This work was developed under the Specific Agreement of Collaboration between the Meteorological State Agency (AEMET) of Spain and the University of Valladolid regarding radiometry, ozone and atmospheric aerosol programmes conducted at Izaña Atmospheric Observatory (IZA), and for the adaptation and integration of the AEMET CIMEL network following the AERONET-RIMA standards.

Póster presentado en: 37th Annual European Meeting on Atmospheric Studies by Optical Methods, celebrado en 2010 en Valladolid. Financial supports from the Spanish MICIIN (ref.CGL2008-05939-CO3-00/CLIandCGL2009-09740) and from the GR-220 Project of the Junta de Castilla y León are gratefully acknowledged.

Aerosol optical depth (AOD) very often shows a distinct diurnal cycle pattern, which seems to be an artifact. This phenomenon is the result of a deficient calibration (or an equivalent effect, as filter degradation). The fictitious sinusoidal shape of the AOD diurnal cycle is a function of the cosine of the solar zenith angle (SZA) and its effect is more accentuated during mid-day. The observation of this effect is not easy at current field stations and only those stations with excellent weather conditions permit an easier detection and correction. By taking advantage of this diurnal cycle behavior because of its dependence on the cosine of the SZA, we propose an improved “in situ” calibration correction procedure. The method is named KCICLO because the determination of a constant K and the behavior of AOD as a cycle (ciclo, in Spanish). It can be seen as a modification of the classical Langley technique (CLT) with the same level of accuracy when CLT is applied at high-altitude stations, and results in an accuracy of 0.2–0.5% for the calibration ratio constant K (or 0.002–0.005 in AOD). The application of this correction method to current and old data series at sunny stations is a significant improvement over “in situ” methods, because no other information beyond the AOD data is necessary.

La caracterización de los aerosoles atmosféricos realizada en el presente estudio se centra en una amplia zona de la región subtropical del hemisferio norte, abarcando el desierto del Sáhara y la región subtropical del Atlántico Nororiental. En primer lugar, se describe el desarrollo y establecimiento de un laboratorio de calibración óptica en el Centro de Investigación Atmosférica de Izaña (CIAI, Agencia Estatal de Meteorología). Este laboratorio es fundamental para el CIAI como centro de calibración de fotómetros solares de la red AERONET (AErosol RObotic NETwork). En segundo lugar, se ha realizado un riguroso análisis del contenido y las propiedades de los aerosoles atmosféricos en la capa límite continental sahariana, la capa límite marina y las condiciones limpias de troposfera libre, a partir de una serie relativamente larga de datos obtenidos a partir de técnicas de fotometría solar y de información auxiliar., Departamento de Física Teórica, Atómica y Óptica