@Article{SilvaEche:2016:GrObCl,
author = "Silva, Abel Antonio and Echer, Mariza Pereira de Souza",
affiliation = "{Instituto de Estudos Avan{\c{c}}ados (IEAv)} and {Instituto
Nacional de Pesquisas Espaciais (INPE)}",
title = "Ground-based observations of clouds through both an automatic
imager and human observation",
journal = "Meteorological Applications",
year = "2016",
volume = "23",
number = "1",
pages = "150--157",
month = "Jan.",
keywords = "clouds, cloud cover, automatic imager, human observation.",
abstract = "The routine to determine the local cloud cover (LCC) drawn from
sky images obtained using a ground-based automatic imager is
validated. Almost 3 years of daily data of LCC and cloud cover
measurements by ground-based human observation (CCHO) were
compared for two Brazilian stations set 6km apart. The linear
fitting between daily values showed a co-efficient of
determination (r(2)) and a percent scattering of points (SD%) of
approximate to 0.77 and approximate to 19.4% respectively. These
results are evidence for the significant similarity between the
two sets of data. On the other hand, the level of difference found
can be explained by the fact that (1) the data refer to
independent micro-scale observations of the sky from stations set
a few kilometres apart and (2) the data were drawn from
interpretations of cloud cover by an automatic imager and a human
observer. The monthly average values of LCC and CCHO showed better
linear fitting parameters r(2)=0.95 and SD%=6.3%. Average
differences of approximate to-10% from LCC to CCHO were found.
These average differences may reflect a systematic bias between
the two processes of measuring cloud cover.",
doi = "10.1002/met.1542",
url = "http://dx.doi.org/10.1002/met.1542",
issn = "1350-4827",
language = "en",
targetfile = "silva_ground.pdf",
urlaccessdate = "27 abr. 2024"
}