In:
Atmospheric Measurement Techniques, Copernicus GmbH, Vol. 14, No. 8 ( 2021-08-19), p. 5657-5699
Abstract:
Abstract. This study introduces an Earth observation (EO)-based system which is capable of operationally estimating and continuously monitoring the
ultraviolet index (UVI) in Europe. UVIOS (i.e., UV-Index Operating System) exploits a synergy of radiative transfer models with high-performance computing and EO data from satellites (Meteosat Second Generation and Meteorological Operational Satellite-B) and retrieval processes (Tropospheric Emission Monitoring Internet Service, Copernicus
Atmosphere Monitoring Service and the Global Land Service). It provides a
near-real-time nowcasting and short-term forecasting service for UV radiation over Europe. The main atmospheric inputs for the UVI simulations
include ozone, clouds and aerosols, while the impacts of ground elevation and surface albedo are also taken into account. The UVIOS output is the UVI at
high spatial and temporal resolution (5 km and 15 min, respectively) for
Europe (i.e., 1.5 million pixels) in real time. The UVI is empirically related to biologically important UV dose rates, and the reliability of this EO-based solution was verified against ground-based measurements from 17
stations across Europe. Stations are equipped with spectral, broadband or
multi-filter instruments and cover a range of topographic and atmospheric
conditions. A period of over 1 year of forecasted 15 min retrievals under
all-sky conditions was compared with the ground-based measurements. UVIOS forecasts were within ±0.5 of the measured UVI for at least 70 % of the data compared at all stations. For clear-sky conditions the agreement was better than 0.5 UVI for 80 % of the data. A sensitivity analysis of EO
inputs and UVIOS outputs was performed in order to quantify the level of
uncertainty in the derived products and to identify the covariance between the accuracy of the output and the spatial and temporal resolution and the
quality of the inputs. Overall, UVIOS slightly overestimated the UVI due to observational uncertainties in inputs of cloud and aerosol. This service
will hopefully contribute to EO capabilities and will assist the provision
of operational early warning systems that will help raise awareness among
European Union citizens of the health implications of high UVI doses.
Type of Medium:
Online Resource
ISSN:
1867-8548
DOI:
10.5194/amt-14-5657-2021
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2021
detail.hit.zdb_id:
2505596-3
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