Scattering of solar radiation by clouds can reduce or enhance solar global irradiance compared to cloudless-sky irradiance at the Earth’s surface. Cloud effects to global irradiance can be described by Cloud Modification Factors (CMF). Depending on strength and duration, irradiance enhancements affect the energy balance of the surface and gain of solar power for electric energy generation. In t...

Hourly irradiance values are essential data to reasonably estimate the electric power production (EPP) from a photovoltaic (PV) system. Worldwide monthly irradiance data are available from meteorological observation satellites; however, adequate hourly data are not widely available in developing countries or rural areas where PV systems are needed most. Aiming to supply such data, this study co...

An equation is derived to express the sensitivity of daily, watercolumn production by phytoplankton in the ocean to variations in irradiance at the sea surface. Assuming no spectral effects, and a vertically uniform chlorophyll profile, the sensitivity is a function only of the dimensionless irradiance. Spectral effects can be accounted for as a function of the chlorophyll concentration. At the...

Total solar irradiance reconstructed between 1978 and 2003 using solar surface magnetic field distributions is compared with three composites of total solar irradiance measurements. A good correspondence is found with the total solar irradiance composite from PMOD/WRC, with no bias between the three cycles. The agreement with the other composites (the ACRIM composite, mainly based on the Active...

The Mauna Loa Observatory record of direct-beam solar irradiance measurements for the years 1958–2010 is analysed to investigate the variation of clear-sky terrestrial insolation with solar activity over more than four solar cycles. The raw irradiance data exhibit a marked seasonal cycle, extended periods of lower irradiance due to emissions of volcanic aerosols, and a long-term decrease in atm...

The lack of reliable data for ground solar irradiance (direct normal and global irradiance) is a major obstacle for the development of adequate policies to promote and take advantage of existing solar technologies. Although the radiation that reaches the outer layers of the atmosphere is well defined and can be easily calculated, the solar irradiance that reaches the ground level where solar co...

OBJECTIVE To evaluate phototherapy practices by measuring the irradiance levels of phototherapy (PT) devices. DESIGN Prospective study. SETTING Tertiary neonatal intensive care units. PATIENTS None. INTERVENTIONS Irradiance levels of PT devices used in the 10 Dutch Neonatal Intensive Care Units (NICUs) were measured according to the local PT practice patterns. The irradiance levels of a...

Deliberate and unintended radio transmissions from Earth propagate into space and could be detected by extraterrestrial watchers over interstellar distances. However, attempts to date at sending messages to extraterrestrial intelligence (METI) have much lower chances of detection than background radio noise from current communication technology on Earth. METI broadcasts are usually transient an...

Method for error analysis of aerosol parameter estimation with assumed noises which are included in the measured solar direct and diffuse irradiance is proposed. The noises included in the measured solar direct and diffuse irradiance are assumed to be Chi-Square probability density function due to the fact that the measured irradiance is represented as output power which is square of output vol...