Articles | Volume 12, issue 1
https://doi.org/10.5194/asr-12-5-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/asr-12-5-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
18 Feb 2015
Estimating the photosynthetically active radiation under clear skies by means of a new approach
W. Wandji Nyamsi
CORRESPONDING AUTHOR
MINES ParisTech, PSL Research University, O. I. E. – Centre Observation, Impacts, Energy, Sophia Antipolis CEDEX, France
B. Espinar
MINES ParisTech, PSL Research University, O. I. E. – Centre Observation, Impacts, Energy, Sophia Antipolis CEDEX, France
MINES ParisTech, PSL Research University, O. I. E. – Centre Observation, Impacts, Energy, Sophia Antipolis CEDEX, France
MINES ParisTech, PSL Research University, O. I. E. – Centre Observation, Impacts, Energy, Sophia Antipolis CEDEX, France
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The present work deals with two well-known databases of hourly mean of solar irradiance that are derived from satellite imagery. The spatial consistency of the uncertainties of these databases is verified against measurements performed within a dense network of ground stations in The Netherlands from the Royal Meteorological Institute KNMI for the period 2014–2017.
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Maxence Descheemaecker, Matthieu Plu, Virginie Marécal, Marine Claeyman, Francis Olivier, Youva Aoun, Philippe Blanc, Lucien Wald, Jonathan Guth, Bojan Sič, Jérôme Vidot, Andrea Piacentini, and Béatrice Josse
Atmos. Meas. Tech., 12, 1251–1275, https://doi.org/10.5194/amt-12-1251-2019, https://doi.org/10.5194/amt-12-1251-2019, 2019
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Mélodie Trolliet, Jakub P. Walawender, Bernard Bourlès, Alexandre Boilley, Jörg Trentmann, Philippe Blanc, Mireille Lefèvre, and Lucien Wald
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Mélodie Trolliet and Lucien Wald
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Yves-Marie Saint-Drenan, Lucien Wald, Thierry Ranchin, Laurent Dubus, and Alberto Troccoli
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William Wandji Nyamsi, Phillipe Blanc, John A. Augustine, Antti Arola, and Lucien Wald
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-512, https://doi.org/10.5194/bg-2017-512, 2018
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This paper proposes a new, fast and accurate method for estimating photosynthetically active radiation at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
William Wandji Nyamsi, Mikko R. A. Pitkänen, Youva Aoun, Philippe Blanc, Anu Heikkilä, Kaisa Lakkala, Germar Bernhard, Tapani Koskela, Anders V. Lindfors, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 10, 4965–4978, https://doi.org/10.5194/amt-10-4965-2017, https://doi.org/10.5194/amt-10-4965-2017, 2017
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This paper proposes a new, fast and accurate method for estimating UV fluxes at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
Philip D. Jones, Colin Harpham, Alberto Troccoli, Benoit Gschwind, Thierry Ranchin, Lucien Wald, Clare M. Goodess, and Stephen Dorling
Earth Syst. Sci. Data, 9, 471–495, https://doi.org/10.5194/essd-9-471-2017, https://doi.org/10.5194/essd-9-471-2017, 2017
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The construction of a bias-adjusted dataset of climate variables at the near surface using ERA-Interim reanalysis is presented. The variables are air temperature, dewpoint temperature, precipitation (daily only), solar radiation, wind speed, and relative humidity.The resulting bias-adjusted dataset is available through the Climate Data Store (CDS) of the Copernicus Climate Change Data Store (C3S), and can be accessed at present from ftp://ecem.climate.copernicus.eu.
Marc Bengulescu, Philippe Blanc, Alexandre Boilley, and Lucien Wald
Adv. Sci. Res., 14, 35–48, https://doi.org/10.5194/asr-14-35-2017, https://doi.org/10.5194/asr-14-35-2017, 2017
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This study investigates the characteristic time-scales of variability found in long-term time-series of daily means of surface solar irradiance (SSI). Estimates of SSI from satellite-derived HelioClim-3 and radiation products from ERA-Interim and MERRA-2 re-analyses are compared to WRDC measurements. It is found that HelioClim-3 renders a more accurate picture of the variability found in ground measurements, not only globally, but also with respect to individual characteristic time-scales.
Mathilde Marchand, Nasser Al-Azri, Armel Ombe-Ndeffotsing, Etienne Wey, and Lucien Wald
Adv. Sci. Res., 14, 7–15, https://doi.org/10.5194/asr-14-7-2017, https://doi.org/10.5194/asr-14-7-2017, 2017
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The solar hourly irradiation received at ground level estimated by the databases HelioClim-3v4, HelioClim-3v5 and Copernicus Atmosphere Monitoring Service (CAMS) Radiation Service are compared to measurements made in stations in Oman and Abu Dhabi. The correlation coefficients are greater than 0.97. The relative bias is less than 5%. Each database captures accurately the temporal and spatial variability of the irradiance field. The three databases are reliable sources to assess solar radiation.
Claire Thomas, Laurent Saboret, Etienne Wey, Philippe Blanc, and Lucien Wald
Adv. Sci. Res., 13, 129–136, https://doi.org/10.5194/asr-13-129-2016, https://doi.org/10.5194/asr-13-129-2016, 2016
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HelioClim-3 (version 4) is a satellite-derived solar surface irradiance database available at d-1 until 2015. To fulfill the requirements of numerous users, a new service based on the principle of persistence has been developed; it provides solar data in real time and forecasts until the end of the current day. The service exhibits good performances for 15 min and 1 h ahead forecasts, and degrades as the temporal horizon increases. Several customers have so far purchased this service.
Marc Bengulescu, Philippe Blanc, and Lucien Wald
Adv. Sci. Res., 13, 121–127, https://doi.org/10.5194/asr-13-121-2016, https://doi.org/10.5194/asr-13-121-2016, 2016
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The continuous wavelet (CWT) and the Hilbert–Huang transforms (HHT) are compared for the analysis of the temporal variability on ten years of daily means of the surface solar irradiance. In both cases, the variability exhibits a plateau between scales of two days and three months that has decreasing power with increasing scale, a spectral peak corresponding to the annual cycle, and a low power regime in-between. The HHT is shown to be suitable for inspecting the variability of the measurements.
Claire Thomas, Etienne Wey, Philippe Blanc, and Lucien Wald
Adv. Sci. Res., 13, 81–86, https://doi.org/10.5194/asr-13-81-2016, https://doi.org/10.5194/asr-13-81-2016, 2016
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Several satellite-derived solar surface irradiance databases provide long-term and homogeneously distributed information on the solar potential at ground level. This paper presents the validation results of three of these databases: HelioClim-3 (versions 4 and 5) and the CAMS radiation service, versus the measurements of 42 stations in Brazil. Despite a slight overestimation of the CAMS radiation service, the three databases are suitable for studies of the solar resources in Brazil.
Mireille Lefèvre and Lucien Wald
Adv. Sci. Res., 13, 21–26, https://doi.org/10.5194/asr-13-21-2016, https://doi.org/10.5194/asr-13-21-2016, 2016
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The new CAMS (Copernicus Atmosphere Monitoring Service) McClear service is a practical easy-to-use tool to estimate the solar direct and global irradiances received at ground level in cloud-free conditions at any place any time. This article presents validation against 1 min measurements made at three very close stations in Israel in desert conditions. The good results demonstrate the accuracy of McClear and its ability to capture the temporal and spatial variability of the irradiance field.
Mohamed Korany, Mohamed Boraiy, Yehia Eissa, Youva Aoun, Magdy M. Abdel Wahab, Stéphane C. Alfaro, Philippe Blanc, Mossad El-Metwally, Hosni Ghedira, Katja Hungershoefer, and Lucien Wald
Earth Syst. Sci. Data, 8, 105–113, https://doi.org/10.5194/essd-8-105-2016, https://doi.org/10.5194/essd-8-105-2016, 2016
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A database of global and diffuse components of the surface solar hourly irradiation measured from 2004 to 2010 at eight Egyptian meteorological stations is presented. At three sites, the direct component is also available. In addition, a series of meteorological variables is provided at the same hourly resolution. The measurements and quality checks applied to the data are detailed. Finally, 13500 to 29000 measurements of global and diffuse hourly irradiation are available at each site.
P. Blanc and L. Wald
Adv. Sci. Res., 13, 1–6, https://doi.org/10.5194/asr-13-1-2016, https://doi.org/10.5194/asr-13-1-2016, 2016
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Time series of hourly measurements or modelled values of surface solar irradiation are increasingly available. Currently, no solar zenith and azimuth angles are associated to each measurement whereas such angles are necessary for handling the measured or modelled irradiations. A method is proposed to assess such angles with a great accuracy. It makes use of two modelled time-series that can be computed using the web site www.soda-pro.com for any site in the world.
Y. Eissa, P. Blanc, L. Wald, and H. Ghedira
Atmos. Meas. Tech., 8, 5099–5112, https://doi.org/10.5194/amt-8-5099-2015, https://doi.org/10.5194/amt-8-5099-2015, 2015
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This study investigates whether the spectral aerosol optical properties of the AERONET stations are sufficient for an accurate modelling of the monochromatic beam and circumsolar irradiances under cloud-free conditions in a desert environment. By comparing the modelled irradiances against reference ground measurements, the monochromatic beam and circumsolar irradiances may very well be modelled using a set of inputs extracted from the AERONET data.
W. Wandji Nyamsi, A. Arola, P. Blanc, A. V. Lindfors, V. Cesnulyte, M. R. A. Pitkänen, and L. Wald
Atmos. Chem. Phys., 15, 7449–7456, https://doi.org/10.5194/acp-15-7449-2015, https://doi.org/10.5194/acp-15-7449-2015, 2015
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A novel model of the absorption of radiation by ozone in the UV bands [283, 307]nm and [307, 328]nm yields improvements in the modeling of the transmissivity in these bands. This model is faster than detailed spectral calculations and is as accurate with maximum errors of respectively 0.0006 and 0.0143. How to practically implement this new parameterization in a radiative transfer model is discussed for the case of libRadtran.
P. Blanc, C. Coulaud, and L. Wald
Adv. Sci. Res., 12, 1–4, https://doi.org/10.5194/asr-12-1-2015, https://doi.org/10.5194/asr-12-1-2015, 2015
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New Caledonia experiences a decrease in surface solar irradiation since 2004, of order of 4% of the mean yearly irradiation, and amounts to 9 W m 2. The preeminent roles of the changes in cloud cover and to a lesser extent, those in aerosol optical depth on the decrease in yearly irradiation are evidenced. The study highlights the role of data sets offering a worldwide coverage in understanding changes in solar radiation and planning large solar energy plants.
J. Badosa, J. Wood, P. Blanc, C. N. Long, L. Vuilleumier, D. Demengel, and M. Haeffelin
Atmos. Meas. Tech., 7, 4267–4283, https://doi.org/10.5194/amt-7-4267-2014, https://doi.org/10.5194/amt-7-4267-2014, 2014
Z. Qu, B. Gschwind, M. Lefevre, and L. Wald
Atmos. Meas. Tech., 7, 3927–3933, https://doi.org/10.5194/amt-7-3927-2014, https://doi.org/10.5194/amt-7-3927-2014, 2014
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The HelioClim-3 database (HC3v3) provides records of surface solar irradiation every 15 min estimated by processing images from the geostationary meteorological Meteosat satellites using climatological data sets of atmospheric properties. A method is proposed to improve a posteriori HC3v3 by combining it with data records of advanced global aerosol property forecasts and physically consistent total column content in water vapour and ozone produced by the MACC projects.
A. Oumbe, Z. Qu, P. Blanc, M. Lefèvre, L. Wald, and S. Cros
Geosci. Model Dev., 7, 1661–1669, https://doi.org/10.5194/gmd-7-1661-2014, https://doi.org/10.5194/gmd-7-1661-2014, 2014
M. Lefèvre, A. Oumbe, P. Blanc, B. Espinar, B. Gschwind, Z. Qu, L. Wald, M. Schroedter-Homscheidt, C. Hoyer-Klick, A. Arola, A. Benedetti, J. W. Kaiser, and J.-J. Morcrette
Atmos. Meas. Tech., 6, 2403–2418, https://doi.org/10.5194/amt-6-2403-2013, https://doi.org/10.5194/amt-6-2403-2013, 2013
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Short summary
We propose an innovative method to estimate the Photosynthetically Active Radiation (PAR) under clear sky conditions derived from the fast approach of Kato et al. (1999). It provides very good results better than the two state-of-the-art empirical methods computing the daily mean of PAR from the daily mean of total irradiance. In addition, this technique may be extended to be able to accurately estimate other spectral quantities taking into account absorption of plants photosynthetic pigments.
We propose an innovative method to estimate the Photosynthetically Active Radiation (PAR) under...
