On the sub-micron aerosol size distribution in a coastal-rural site at El Arenosillo Station (SW – Spain)

This study focuses on the analysis of the sub-micron aerosol characteristics at El Arenosillo Station, a rural and coastal environment in South-western Spain between 1 August 2004 and 31 July 2006 (594 days). The mean total concentration (NT) was 8660 cm−3 and the mean concentrations in the nucleation (NNUC), Aitken (NAIT) and accumulation (NACC) particle size ranges were 2830 cm−3, 4110 cm−3 and 1720 cm−3, respectively. Median size distribution was characterised by a single-modal fit, with a geometric diameter, median number concentration and geometric standard deviation of 60 nm, 5390 cm−3 and 2.31, respectively. Characterisation of primary emissions, secondary particle formation, changes to meteorology and long-term transport has been necessary to understand the seasonal and annual variability of the total and modal particle concentration. Number concentrations exhibited a diurnal pattern with maximum concentrations around noon. This was governed by the concentrations of the nucleation and Aitken modes during the warm seasons and only by the nucleation mode during the cold seasons. Similar monthly mean total concentrations were observed throughout the year due to a clear inverse variation between the monthly mean NNUC and NACC. It was related to the impact of desert dust and continental air masses on the monthly mean particle levels. These air masses were associated with high values of NACC which suppressed the new particle formation (decreasing NNUC). Each day was classified according to a land breeze flow or a synoptic pattern influence. The median size distribution for desert dust and continental aerosol was dominated by the Aitken and accumulation modes, and marine air masses were dominated by the nucleation and Aitken modes. Particles moved offshore due to the land breeze and had an impact on the particle burden at noon, especially when the wind was blowing from the NW sector in the morning during summer time. This increased NNUC and NAIT by factors of 3.1 and 2.4, respectively. Nucleation events with the typical "banana" shape were characterised by a mean particle nucleation rate of 0.74 cm−3 s−1, a mean growth rate of 1.96 nm h−1 and a mean total duration of 9.25 h (starting at 10:55 GMT and ending at 20:10 GMT). They were observed for 48 days. Other nucleation events were identified as those produced by the emissions from the industrial areas located at a distance of 35 km. They were observed for 42 days. Both nucleation events were strongly linked to the marine air mass origin

Long period/large scale oscillations of temperature during the DYANA campaign

International audienceDuring the DYANA campaign (January-March 1990) vertical temperature profiles were measured in the middle atmosphere above 11 rocket and four lidar stations in the northern hemisphere. Strong temperature variations were observed, especially at the medium to high latitude stations. Time series analysis was applied, and most oscillations were found to be quasi-periodic only, and restricted to certain altitude levels. Solely the longest periods (>4 weeks) and the shortest periods (around 5 days) were consisterrtly observed in the whole altitude regime, and were, therefore, further analysed. These temperature variations were found to be compatible with the assumption that the Quasi-Stationary Planetary Wave No. 1 (QSW 1) of the CIRA 1990 Model Atmosphere was modulated with the respective periods. Especially close similarity of the vertical phase structures was obtained. The amplitudes measured were, however, much larger than those of the model, and hence some amendment to the model may be appropriate. The importance of QSW 1 modulation appears to be considerable, as more than 50% of the temperature variance could be ascribed to it. The DYANA results were checked by an analysis of respective data from two other campaigns (Winter Anomaly campaign, 1976, and MAP/WINE campaign, 1984). Essentially the same results were obtained. Considering the strength of QSW 1 control, the midwinter middle atmosphere shows itself to be quite strongly and persisterrtly structured in both the vertical and horizontal directions. This applies to all parts of the stratosphere and mesosphere

Basic features of large-scale processes in the middle atmosphere during DYANA

International audienceLarge-scale processes in the stratosphere and mesosphere were investigated for the DYANA period, mainly on the basis of rocket sounding series and satellite-based maps. It was found that undisturbed circulation prevailed during the early winter period with low stratospheric temperatures near the Pole. Periodic warm pulses appeared in January in the upper stratosphere and an interrse warming was observed at these levels in early February, the downward penetration of which (below 25–30 km) was relatively confined. Wavenumber 1 predominated during the warming. In late February the cold cyclonic vortex was restored near the Pole and this persisted into March

A Decade of GRB Follow-Up by BOOTES in Spain (2003-2013)

This article covers ten years of GRB follow-ups by the Spanish BOOTES stations: 71 follow-ups providing 23 detections. Follow-ups by BOOTES-1B from 2005 to 2008 were given in a previous article and are here reviewed and updated, and additional detection data points are included as the former article merely stated their existence. The all-sky cameras CASSANDRA have not yet detected any GRB optical afterglows, but limits are reported where available.The authors appreciate the auspices of INTA, IHSM-UMA/CSIC, and UMA as well as the financial support by the Junta de Andaluca and the Spanish Ministry of Economy and Competitiveness through the Research Projects P07-TIC-03094, P12-TIC2839, AYA2009-14000-C03-01, AYA 2010-39727-C03-01, and AYA-2015-71718-R. Martin Jelinek was supported by the postdoctoral fellowship of the Czech Academy of Sciences. This study was carried out in the framework of the Unidad Asociada IAA-CSIC at the Group of Planetary Science of ETSI-UPV/EHU. This work was supported by the Ikerbasque Foundation for Science. The Czech CVUT FEL team acknowledges the support by GA CR Grant 13-33324S.Peer Reviewe