Paper Session II-B - Principles of Forming the Ground/ Space System for the Forecast of Natural and Technogenic Dangers

It is known, that an essential impact on natural, technogenic, social and other processes on the Earth is made by phenomena occurring on the Sun and within the Earth\u27s near space environment. This is the so called space weather , that causes natural calamities, accidents and disasters, thus influencing the health and people\u27s psychology, etc

Shipborne lidar measurements showing the progression of the tropical reservoir of volcanic aerosol after the June 1991 Pinatubo eruption

International audienceA key limitation of volcanic forcing datasets for the Pinatubo period is the large uncertainty that remains with respect to the extent of the optical depth of the Pinatubo aerosol cloud in the first year after the eruption, the saturation of the SAGE-II instrument restricting it to only be able to measure the upper part of the aerosol cloud in the tropics. Here we report the recovery of stratospheric aerosol measurements from two shipborne lidars, both of which measured the tropical reservoir of volcanic aerosol produced by the June 1991 Mount Pinatubo eruption. The lidars were on board two Soviet vessels, each ship crossing the Atlantic, their measurement datasets providing unique observational transects of the Pinatubo cloud across the tropics from Europe to the Caribbean (40 to 8 N) from July to September 1991 (the Professor Zubov ship) and from Europe to south of the Equator (40 N to 8 S) between January and February 1992 (the Professor Vize ship). Our philosophy with the data recovery is to follow the same algorithms and parameters that appear in the two peer-reviewed articles that presented these datasets in the same issue of GRL in 1993, and here we provide all 48 lidar soundings made from the Professor Zubov and 11 of the 20 conducted from the Professor Vize, ensuring we have reproduced the aerosol backscatter and extinction values in the figures of those two papers. These original approaches used thermodynamic properties from the CIRA-86 standard atmosphere to derive the molecular backscattering, vertically and temporally constant values applied for the aerosol backscatter-Toextinction ratio, and the correction factor of the aerosol backscatter wavelength dependence.We demonstrate this initial validation of the recovered stratospheric aerosol extinction profiles, providing full details of each dataset in this papers Supplement S1, the original profiles of backscatter ratio, and the calculated profiles of aerosol backscatter and extinction. We anticipate these datasets will provide potentially important new observational case studies for modelling analyses, including a 1-week series of consecutive soundings (in September 1991) at the same location showing the progression of the entrainment of part of the Pinatubo plume into the upper troposphere and the formation of an associated cirrus cloud. The Zubov lidar dataset illustrates how the tropically confined Pinatubo aerosol cloud transformed from a highly heterogeneous vertical structure in August 1991, maximum aerosol extinction values around 19 km for the lower layer and 23-24 for the upper layer, to a more homogeneous and deeper reservoir of volcanic aerosol in September 1991. We encourage modelling groups to consider new analyses of the Pinatubo cloud, comparing the recovered datasets, with the potential to increase our understanding of the evolution of the Pinatubo aerosol cloud and its effects

Ship borne lidar measurements in the Atlantic of the 1991 Mt Pinatubo aerosol cloud

The dataset consists of two ship-borne aerosols scattering ratio lidar datasets in the early stages of the stratospheric aerosols produced by the June 1991 Mount Pinatubo eruption. The Russian vessel Prof. Zubov ship Atlantic transect from Europe to the Caribbean from July to September 1991 and Prof. Vize ship transect from Europe to south of the Equator between January and February 1992. All the 48 reported measurements at the Prof. Zubov were rescued but only 11 of the 20 measurements conducted by Prof. Vize were found. We used the same algorithms and parameters appearing in the only two articles published with this datasets to reproduce the aerosols extinction values those papers reported and showed in its figures. Following this criteria the CIRA-86 atmosphere was used to derive the molecular backscattering, vertical and temporal constant values of the aerosols backscattering to extinction ratio and for the correction factor of the aerosols backscattering wavelength dependence. The dataset consists of profiles of lidar aerosols backscattering to extinction profiles ratios and the derived aerosols backscattering and aerosols extinction profiles. Each profile contains information about the latitude, longitude, date and time it was measured

2. Morphology and dynamics of the Pinatubo aerosol layer in the northern hemisphere as detected from a ship-borne lidar

International audienceScattering ratios of the Pinatubo aerosol layer obtained by the ship-borne lidar of the Roscomhydromet of Russia on-board PROFESSOR ZUBOV are presented. During a campaign primarily in the low-latitude (8°N-43°N) Atlantic Ocean, 48 days of data were obtained within the 73 day period spanning 11-July and 21-September of 1991 [Avdyushin et al., 1992]. These data show the aerosol cloud to be primarily in the 16-27 km altitude region, with a high degree of variability in the vertical structure and in the longitudinal structure, and to a lesser degree, in the latitudinal structure. Scattering ratios of up to 50 were recorded in the multi-layered structure which was often observed. These are the first lidar observations showing a high degree of zonal variability of the vertical structure of the aerosol layer. We show the latitudinal range of the Pinatubo aerosol cloud in the northern hemisphere over a 2 month period and estimate the latitudinal dispersion rate for the months of the measurements to be approximately 5° latitude per month. A clear periodic variability was observed in the altitude structure during the entire data-set primarily within 8°N-22°N latitude and within the altitude region of the layer, from which a mean zonal wind profile was produced by a spectral analysis of the aerosol profiles

1. Spatial and temporal evolution of the optical thickness of the Pinatubo aerosol cloud in the northern hemisphere from a network of ship-borne and stationary lidars

International audienceThe vertical profiles of the extinction coefficient and the total optical thickness of the Pinatubo aerosol layer obtained from a network of 5 Rayleigh-Mie lidars are presented here. Three ship-borne lidars (PROFESSOR ZUBOV†, PROFESSOR VIZE†, HENRI POINCARE*) and two fixed lidar stations (OHP* and CEL*) are operated respectively by the Roscomhydromet†, of Russia and of the Service d'Aeronomie du CNRS* of France. The measurements presented are in the altitude range 15-35 km. They were obtained between July 1991 - April 1992 and cover 8°S-60°N latitude and 80°W-6°E longitude. This represents extensive coverage of the western sector of the northern hemisphere, which is partly coincident with UARS satellite coverage. Optical depths of up to 0.2 were observed and maximum extinction coefficient values of 0.08 km-1 were obtained at 24 km and 18°N latitude