Periodic Reporting for period 2 - ARISE2 (Atmospheric dynamics Research InfraStructure in Europe)
Reporting period: 2017-03-01 to 2018-08-31
The ARISE (Atmospheric dynamics Research InfraStructure in Europe) project (http://arise-project.eu) integrates complementary station networks, including the infrasound International Monitoring System (IMS) developed for the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, the lidar Network for the Detection of Atmospheric Composition Changes (NDACC), multi-instrument reference stations (ALOMAR/Northern Europe, OHP/Middle latitude, Maïdo/Tropics) and complementary infrasound networks, radars, radiometers and satellite observations. The objective to determine the origin of uncertainties in Numerical Weather Prediction (NWP) models such as the one of the European Centre for Medium-Range Weather Forecasts (ECMWF) and to provide new data sets about MA variability in the Europe-Africa longitude sector from low latitude to polar regions for future assimilation in models.
ARISE observations describe weather related disturbances such as tropical convection, mountain waves, stratospheric warming events as well as natural hazards such as volcanos, severe weather or meteorites. New methodologies and intermediate models are developed in response to an increasing demand of data products, available in the ARISE data portal (demonstrator).
The review paper (http://link.springer.com/article/10.1007/s10712-017-9444-0) describes main ARISE results.
In Work Package 2, the ARISE observation network was optimized by the improvement of (i) the three ARISE reference stations (ALOMAR, OHP, Maïdo) with an upgrade of the observation duration and the instrument performances (ii) one pilot site (IS26) to assess the added value of lidar observations collocated to infrasound IMS stations, (iii) integration of dense national infrasound networks.
Work Package 3 was dedicated to ARISE innovative instruments. Several prototypes have been calibrated in the reference stations and replicated. The portable lidar, CORAL, is now fully automatic and observation campaigns of several months in Germany and Argentina provided new relevant data sets. Improved processing tools enable standardized data analysis and extraction of new parameters. Furthermore, synergies between infrasound and lidar were explored. The reprocessing of low frequency IMS data provided gravity ave data exploited in WP6 for gravity wave climatologies.
In Work Package 4 dedicated to integration of infrastructures, the high-latitude hub of ground-based stations was shown to function as a proxy for a fully-fledged multi-instrument ARISE station providing new datasets from lidar, radars, and an infrasound array, located in northern Scandinavia. Combined datasets were used for MA analyse during a major sudden stratospheric warming event and a set of industrial explosions. Steps were made toward automating MA remote sensing. The conclusions are expected to be applicable to other observatories. Unified approaches provide gravity wave potential energy from lidar datasets recorded at different latitudes
In Work Package 5 related to extreme events, products and services dedicated to remote monitoring of severe weather and volcanoes are developed. The proof of concept and prototype of the VIS (Volcano Information System) have been achieved. Near-real time notification of the Volcano Infrasound Early-Warning (VIEW) system are sent to the ARISE portal for use by end-users, such as Toulouse Volcanic Ash Advisory Council. A sudden stratospheric warming event database from ARISE measurements and re-analysis is provided for weather models. Ground truth events were further catalogued and infrasound simulations integrate more accurate disturbances in the MA profiles.
Work Package 6 proposes new methods to use various ARISE data to benefit weather and climate modelling. IMS infrasound data was combined with meteorological data allowing gravity wave parameters to be calculated in order to improve NWP models. This analysis provided gravity wave climatologies available on the ARISE data portal. Infrasound inversions determine some MA properties to assess the effects of atmospheric variability in models. This also concerns atmospheric forecasts during sudden stratospheric warming events. Temperature lidar data was used to determine temperature bias within ECMWF re-analyses and seasonal forecasts.
The ARISE Work Package 7 is dedicated to the data portal (https://arise-portal.eu/) which is designed to be the most complete, accurate and attractive reference platform for MA scientific communities, with high societal impact. Data from 24 datasets based on 13 different atmospheric observation technologies are available via the ARISE portal. Inter-comparisons of data with ERA-5 models are possible. In addition, nine advanced multi-technology data products are also available, enabling extreme event studies and model validations, for example. Operational and prototypical services are based on these data sets in collaboration with CTBTO and the Toulouse Volcanic Ash Advisory Center, notably for volcano monitoring.
The ARISE multi-instrument observations showed biases in weather prediction models, concerning the temperature and horizontal wind, originating from middle atmosphere variability at unresolved time scales. ARISE showed that improved characterization of the stratosphere where observations are sparse can improve weather forecasts especially when forecasts initialize close to sudden stratospheric warming events, when a correlation with surface weather patterns is expected at sub-seasonal timescales. Improved forecasting at scales of several weeks obviously presents large economic and social implications on society.
The Volcano Information System (VIS) implemented in the ARISE platform and presently calibrated using Etna monitoring will be very relevant for remote monitoring of non-instrumented volcanoes. The ARISE team demonstrated the possibility to predict the ash plume height and mass eruption rate based on the infrasound signals associated to the eruptions with a large impact for the aviation security.