Reflectance measurements of crop plants and canopies show promise for guiding within-season, variable-rate nitrogen (N) application. Most research results have been obtained around solar noon with clear skies. However, for practical application, the system must work under cloudy skies or away from solar noon. The objective of this work was to assess the effect of cloud conditions on reflectance...

This study documents multidecadal variations in low-level, upper-level, and total cloud cover over land and ocean independently obtained from surface synoptic observations and from satellite data produced by the International Satellite Cloud Climatology Project. Substantial agreement exists between global mean time series of surfaceand satellite-observed upper-level cloud cover, indicating that...

The paper analyzes the influence of atmospheric circulation on cloudiness and cloud types during July August 2016 in Petuniabukta Svalbard-Lufthavn. For meteorological parameters, basic statistical measures were calculated average diurnal patterns analyzed. Taking data from reanalysis (NCEP/NCAR-The National Centers for Atmospheric Prediction/The Center Research) regarding mean sea-level pressu...

In solar resource assessment, the climatological environment of target area is objectively quantified by cloudiness or clear sky index, which defined as ratio global horizontal irradiance to insolation. The model calculates incoming on ground surface considering several atmospheric parameters such water vapor and aerosol optical depth. This study investigated importance depth for deriving in ra...

This work concerns the 10? North, 20? North African band. Area renowned for having some of poorest countries in world. It is also home to Sahelian strip and part Sahara. The this zone have a relatively low electrification rate compared enlightened country. To solve problem, these want turn renewable energies such as photovoltaics (renewable energy obtained through solar radiation). Therefore, u...

The influence of clouds on Earth ́s radiation balance is a key component of the atmospheric system. Therefore, the determination of cloud cover is an important activity traditionally performed by human observations and broadcasted by meteorological services observers in Synop and Metar reports. However, human observations are subject to large errors of estimation, and their temporal resolution i...

Objective: To estimate the monthly average global solar irradiance (Rg), using observed cloudiness data (% of cloudy days), as well its spatial distribution for state Tabasco, Mexico.Design/Methodology/Approximation: The proposed model by Tejeda-Martínez et al. (1999) was adjusted to Rg 35 meteorological stations in Tabasco. adjustment performed with daily fromeight automated weather and from e...

Collocated in time and space, top-of-the-atmosphere measurements of the Earth radiation budget (ERB) and cloudiness from passive scanning radiometers, and lidarand radar-in-space measurements of multilayered cloud systems, are the required combination to improve our understanding of the role of clouds and radiation in climate. Experiments to fly multiple satellites "in formation" to measure sim...