6 research outputs found
Multi-model ensemble simulations of olive pollen distribution in Europe in 2014 : current status and outlook
The paper presents the first modelling experiment of the
European-scale olive pollen dispersion, analyses the quality of the
predictions, and outlines the research needs. AÂ 6-model strong ensemble of
Copernicus Atmospheric Monitoring Service (CAMS) was run throughout the olive season
of 2014, computing the olive pollen distribution. The simulations have been
compared with observations in eight countries, which are members of the European
Aeroallergen Network (EAN). Analysis was performed for individual models, the
ensemble mean and median, and for a dynamically optimised combination of the
ensemble members obtained via fusion of the model predictions with
observations. The models, generally reproducing the olive season of 2014,
showed noticeable deviations from both observations and each other. In
particular, the season was reported to start too early by 8Â days, but for some
models the error mounted to almost 2 weeks. For the end of the season, the
disagreement between the models and the observations varied from a nearly
perfect match up to 2 weeks too late. AÂ series of sensitivity studies
carried out to understand the origin of the disagreements revealed the crucial role
of ambient temperature and consistency of its representation by the
meteorological models and heat-sum-based phenological model. In
particular, a simple correction to the heat-sum threshold eliminated the
shift of the start of the season but its validity in other years remains to be checked. The
short-term features of the concentration time series were reproduced better,
suggesting that the precipitation events and cold/warm spells, as well as the
large-scale transport, were represented rather well. Ensemble averaging led to
more robust results. The best skill scores were obtained with data fusion,
which used the previous days' observations to identify the optimal weighting
coefficients of the individual model forecasts. Such combinations were tested
for the forecasting period up to 4Â days and shown to remain nearly optimal
throughout the whole period
Spatial and temporal variations in airborne Ambrosia pollen in Europe
We acknowledge support from EU COST Action FA1203 "Sustainable management of Ambrosia artemisiifolia in Europe (SMARTER)". This work was partly financed by the following COST Short Term Scientific Missions: COST-STSM-FA1203-020215-053027 to CT, COST-STSM-FA1203-20573, ECOST-STSM-FA1203-250415-058150. Skjøth is supported by European Commission through a Marie Curie Career Integration Grant (Project ID CIG631745)Unidad de excelencia MarĂa de Maeztu MdM-2015-0552The European Commission Cooperation in Science and Technology (COST) Action FA1203 "SMARTER" aims to make recommendations for the sustainable management of Ambrosia across Europe and for monitoring its efficiency and cost-effectiveness. The goal of the present study is to provide a baseline for spatial and temporal variations in airborne Ambrosia pollen in Europe that can be used for the management and evaluation of this noxious plant. The study covers the full range of Ambrosia artemisiifolia L. distribution over Europe (39°N-60°N; 2°W-45°E). Airborne Ambrosia pollen data for the principal flowering period of Ambrosia (August-September) recorded during a 10-year period (2004-2013) were obtained from 242 monitoring sites. The mean sum of daily average airborne Ambrosia pollen and the number of days that Ambrosia pollen was recorded in the air were analysed. The mean and standard deviation (SD) were calculated regardless of the number of years included in the study period, while trends are based on those time series with 8 or more years of data. Trends were considered significant at p < 0.05. There were few significant trends in the magnitude and frequency of atmospheric Ambrosia pollen (only 8% for the mean sum of daily average Ambrosia pollen concentrations and 14% for the mean number of days Ambrosia pollen were recorded in the air). The direction of any trends varied locally and reflected changes in sources of the pollen, either in size or in distance from the monitoring station. Pollen monitoring is important for providing an early warning of the expansion of this invasive and noxious plant
MACC regional multi-model ensemble simulations of birch pollen dispersion in Europe
This paper presents the first ensemble modelling experiment in relation to birch pollen in Europe. The sevenmodel European ensemble of MACC-ENS, tested in trial simulations over the flowering season of 2010, was run through the flowering season of 2013. The simulations have been compared with observations in 11 countries, all members of the European Aeroallergen Network, for both individual models and the ensemble mean and median. It is shown that the models successfully reproduced the timing of the very late season of 2013, generally within a couple of days from the observed start of the season. The end of the season was generally predicted later than observed, by 5 days or more, which is a known feature of the source term used in the study. Absolute pollen concentrations during the season were somewhat underestimated in the southern part of the birch habitat. In the northern part of Europe, a recordlow pollen season was strongly overestimated by all models. The median of the multi-model ensemble demonstrated robust performance, successfully eliminating the impact of outliers, which was particularly useful since for most models this was the first experience of pollen forecasting
Spatial and temporal variations in airborne Ambrosia pollen in Europe
The European Commission Cooperation in Science and Technology (COST) Action FA1203 “SMARTER” aims to make recommendations for the sustainable management of Ambrosia across Europe and for monitoring its efficiency and cost-effectiveness. The goal of the present study is to provide a baseline for spatial and temporal variations in airborne Ambrosia pollen in Europe that can be used for the management and evaluation of this noxious plant. The study covers the full range of Ambrosia artemisiifolia L. distribution over Europe (39°N–60°N; 2°W–45°E). Airborne Ambrosia pollen data for the principal flowering period of Ambrosia (August–September) recorded during a 10-year period (2004–2013) were obtained from 242 monitoring sites. The mean sum of daily average airborne Ambrosia pollen and the number of days that Ambrosia pollen was recorded in the air were analysed. The mean and standard deviation (SD) were calculated regardless of the number of years included in the study period, while trends are based on those time series with 8 or more years of data. Trends were considered significant at p < 0.05. There were few significant trends in the magnitude and frequency of atmospheric Ambrosia pollen (only 8% for the mean sum of daily average Ambrosia pollen concentrations and 14% for the mean number of days Ambrosia pollen were recorded in the air). The direction of any trends varied locally and reflected changes in sources of the pollen, either in size or in distance from the monitoring station. Pollen monitoring is important for providing an early warning of the expansion of this invasive and noxious plant