@article{Chrysoulakis2018,
title = {Urban energy exchanges monitoring from space},
author = {Nektarios Chrysoulakis and Sue Grimmond and Christian Feigenwinter and Fredrik Lindberg and Jean-Philippe Gastellu-Etchegorry and Mattia Marconcini and Zina Mitraka and Stavros Stagakis and Ben Crawford and Frans Olofson and Lucas Landier and William Morrison and Eberhard Parlow },
editor = {nature.com},
url = {http://urbanfluxes.eu/wp-content/uploads/2018/07/UF_Overview_final.pdf},
doi = {10.1038/s41598-018-29873-x},
issn = {2045-2322},
year = {2018},
date = {2018-07-31},
journal = { nature.com },
volume = {Scientific Reports volume},
number = {8},
pages = {11498},
abstract = {One important challenge facing the urbanization and global environmental change community is to understand the relation between urban form, energy use and carbon emissions. Missing from the current literature are scientific assessments that evaluate the impacts of different urban spatial units on energy fluxes; yet, this type of analysis is needed by urban planners, who recognize that local scale zoning affects energy consumption and local climate. Satellite-based estimation of urban energy fluxes at neighbourhood scale is still a challenge. Here we show the potential of the current satellite missions to retrieve urban energy budget fluxes, supported by meteorological observations and evaluated by direct flux measurements. We found an agreement within 5% between satellite and in-situ derived net all-wave radiation; and identified that wall facet fraction and urban materials type are the most important parameters for estimating heat storage of the urban canopy. The satellite approaches were found to underestimate measured turbulent heat fluxes, with sensible heat flux being most sensitive to surface temperature variation (−64.1, +69.3 W m−2 for ±2 K perturbation). They also underestimate anthropogenic heat fluxes. However, reasonable spatial patterns are obtained for the latter allowing hot-spots to be identified, therefore supporting both urban planning and urban climate modelling.},
keywords = {anthropogenic heat emission, Anthropogenic Heat Flux, Concentration profiles, Copernicus Sentinels, Earth Observation, Eddy-covariance, Flux measurements, Ground-based thermography, Image classification, reducing, Sensor view modelling, Street canyon, Thermographic camera modelling, Understanding, Upwelling longwave radiation, urban, Urban Climate, Urban Energy Budget, urban heat fluxes, Urban meteorology},
pubstate = {published},
tppubtype = {article}
}

@article{Feigenwinter2018,
title = {Spatial Distribution of Sensible and Latent Heat Flux in the city of Basel (Switzerland)},
author = {Christian Feigenwinter and Roland Vogt and Eberhard Parlow and Fredrik Lindberg and Mattia Marconcini and Fabio Del Frate and Nektarios Chrysoulakis},
doi = {10.1109/JSTARS.2018.2807815},
issn = {2151-1535},
year = {2018},
date = {2018-03-18},
journal = {IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing},
abstract = {Urban surfaces are a complex mixture of different land covers and surface materials; the relative magnitudes of the surface energy balance components therefore vary widely across a city. Eddy covariance (EC) measurements provide the best estimates of turbulent heat fluxes but are restricted to the source area. Land surface modeling with earth observation (EO) data is beneficial for extrapolation of a larger area since citywide information is possible. Turbulent sensible and latent heat fluxes are calculated by a combination of micrometeorological approaches (the aerodynamic resistance method, ARM), EO data, and GIS techniques. Input data such as land cover fractions and surface
temperatures are derived from Landsat 8 OLI and TIRS, urban morphology was calculated from high-resolution digital building models and GIS data layers, and meteorological data were provided by flux tower measurements. Twenty-two Landsat scenes covering all seasons and different meteorological conditions were analyzed. Sensible heat fluxes were highest for industrial areas, railway stations, and areas with high building density, mainly corresponding to the pixels with highest surface-to-air temperature differences.
The spatial distribution of latent heat flux is strongly related to the
saturation deficit of vapor and the (minimum) stomatal resistance
of vegetation types. Seasonal variations are highly dependent on
meteorological conditions, i.e., air temperature, water vapor saturation
deficit, and wind speed. Comparison of measured fluxes
with modeled fluxes in the weighted source area of the flux towers
is moderately accurate due to known drawbacks in the modeling
approach and uncertainties inherent to EC measurements, particularly
in urban areas.},
keywords = {Basel, Flux measurements, Urban Energy Budget},
pubstate = {published},
tppubtype = {article}
}

@conference{Chrysoulakisj2017,
title = {Anthropogenic Heat Flux Estimation from Space: Results of the second phase of the URBANFLUXES Project},
author = {Nektarios Chrysoulakis and Mattia Marconcini and Jean-Philippe Gastellu-Etchegorry and Sue Grimmond and Christian Feigenwinter and Fredrik Lindberg and Fabio Del-Frate and Judith Klostermann and Zina Mitraka and Thomas Esch and Lucas Landier and Andy Gabey and Eberhard Parlow and Frans Olofson},
editor = {Joint Urban Remote Sensing Event (JURSE)},
url = {http://urbanfluxes.eu/wp-content/uploads/2018/01/2017_Chrysoulakis_et_al_JURSE.pdf},
doi = {10.1109/JURSE.2017.7924591},
issn = {978-1-5090-5808-2},
year = {2017},
date = {2017-05-11},
abstract = {The H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to
retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the impacts of UEB fluxes on urban heat island and consequently on energy consumption in cities. This will lead to the development of tools and strategies to mitigate these effects, improving thermal comfort and energy efficiency. In URBANFLUXES, the anthropogenic heat flux is estimated as a residual of UEB. Therefore, the rest UEB components, namely, the net all-wave radiation (Q*), the net change in heat storage (ΔQs) and the turbulent sensible (QH) and latent (QE) heat fluxes are independently estimated from Earth Observation (EO), whereas the advection term is included in the error of the anthropogenic heat flux estimation from the UEB closure. The project exploits Sentinels observations, which provide improved data quality, coverage and revisit times and increase the value of EO data for scientific work and future emerging applications. These observations can reveal novel scientific insights for the detection and monitoring of the spatial distribution of the urban energy budget fluxes in cities, thereby generating new EO opportunities. URBANFLUXES thus exploits the European capacity for spaceborne observations to enable the development of operational services in the field of urban environmental monitoring and energy efficiency in cities.
},
keywords = {Copernicus Sentinels, Earth Observation, Urban Climate, Urban Energy Budget},
pubstate = {published},
tppubtype = {conference}
}

@conference{Chrysoulakis2017,
title = {Anthropogenic Heat Flux Estimation from Space: Results of the second phase of the URBANFLUXES Project},
author = {Nektarios Chrysoulakis and Mattia Marconcini and Jean-Philippe Gastellu-Etchegorry and Sue Grimmond and Christian Feigenwinter and Fredrik Lindberg and Fabio Del Frate and Judith Klostermann and Zina Mitraka and Thomas Esch and Lucas Landier and Andy Gabey and Eberhard Parlow and Frans Olofson



},
editor = {EGU General Assembly 2017
},
url = {http://urbanfluxes.eu/wp-content/uploads/2018/01/2017_Chrysoulakis_et_al_EGU.pdf},
year = {2017},
date = {2017-01-01},
journal = {Geophysical Research Abstracts Vol. 19, EGU2017-2819, 2017 EGU General Assembly 2017},
volume = {Vol. 19, EGU2017-2819},
number = {19},
abstract = {The H2020-Space project URBANFLUXES (URBan ANthrpogenic heat FLUX from Earth observation Satellites) investigates the potential of Copernicus Sentinels to retrieve anthropogenic heat flux, as a key component of the Urban Energy Budget (UEB). URBANFLUXES advances the current knowledge of the impacts of UEB fluxes on urban heat island and consequently on energy consumption in cities. In URBANFLUXES, the anthropogenic heat flux is estimated as a residual of UEB. Therefore, the rest UEB components, namely, the net all-wave radiation, the net change in heat storage and the turbulent sensible and latent heat fluxes are independently estimated from Earth Observation (EO), whereas the advection term is included in the error of the anthropogenic heat flux estimation from the UEB closure. The Discrete Anisotropic Radiative Transfer (DART) model is employed to improve the estimation of the net all-wave radiation balance, whereas the Element Surface Temperature Method (ESTM), adjusted to satellite observations is used to improve the estimation the estimation of the net change in heat storage. Furthermore the estimation of the turbulent sensible and latent heat fluxes is based on the Aerodynamic Resistance Method (ARM). Based on these outcomes, QF is estimated by regressing the sum of the turbulent heat fluxes versus the available energy. In-situ flux measurements are used to evaluate URBANFLUXES outcomes, whereas uncertainties are specified and analyzed. URBANFLUXES is expected to prepare the ground for further innovative exploitation of EO in scientific activities (climate variability studies at local and regional scales) and future and emerging applications (sustainable urban planning, mitigation technologies) to benefit climate change mitigation/adaptation. This study presents the results of the second phase of the project and detailed information on URBANFLUXES is available at: http://urbanfluxes.eu},
keywords = {Copernicus Sentinels, Earth Observation, mitigation technologies, sustainable urban planning, Urban Climate, Urban Energy Budget},
pubstate = {published},
tppubtype = {conference}
}

@conference{Chrysoulakis2016b,
title = {Urban Energy Budget estimation from Sentinels: The URBANFLUXES project},
author = {Nektarios Chrysoulakis and Wieke Heldens and Jean-Philippe Gastellu-Etchegorry and Sue Grimmond and Christian Feigenwinter and Fredrik Lindberg and Fabio Del Frate and Judith Klostermann and Zina Mitraka and Thomas Esch and Ahmad Al Bitar and Andrew Gabey and Eberhard Parlow and Frans Olofson },
url = {http://urbanfluxes.eu/wp-content/uploads/2017/02/A40_2016_Chrysoulakis_et_al_ESALPS_URBANFLUXES.pdf},
year = {2016},
date = {2016-12-31},
keywords = {estimation, Sentinels, The URBANFLUXES project, Urban Energy Budget},
pubstate = {published},
tppubtype = {conference}
}