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| | BIOLOGICALLY EFFECTIVE ULTRAVIOLET |
 | | Action spectra are necessary in assessing the biological effects of changes in the spectral irradiance due to changes in ozone concentrations. | | | The biologically effective irradiance can be determined if suitable filters and sensors are selected to provide a spectral response similar to the action spectrum in consideration. | | | Figure 4 – Comparison of action spectra with the action spectrum for (1) photoconjunctivitis of the human eye, (2) human erythema and (3) plant damage and the resulting spectral biologically effective spectral irradiances for (4) photoconjunctivitis, (5) human erythema and (6) plant damage. |
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http://www.photobiology.com/UVR98/wongrev/index.htm
(5837 words)
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| | UV-B RADIATION and OZONE DEPLETION--Effects on Humans, Animals, Plants, Microorganisms, and Materials |
| | What UV-B irradiation does to some of the subsystems is known for certain experimental conditions, but this knowledge is far from sufficient to predict the overall outcome for the entire system. | | | UV-B radiation contributes significantly to the aging of the skin and eyes, and it is the UV-B range that is the most effective in causing skin cancer. | | | Many immune responses are not affected by UV irradiation. |
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http://www.ciesin.org/docs/001-540/001-540.html
(10330 words)
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| | Chapter 10 Weathering Test Methods |
| | The intensity of light of each wavelength falling on the surface of a material, i.e., the irradiance level of exposure, is determined by the number of photons associated with each wavelength of light. | | | The acceleration factor is the time to failure (or change in property) under the accelerated test condition divided by the time to failure (or change in property) under natural exposure, both evaluated by the same technique. | | | Interior irradiances, in contrast, depend highly on glass filtering, angles and shading, etc. Well-equipped exposure facilities offer spectral radiometer measurements of interior locations in full system exposures. |
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http://www.atlas-mts.com/products/natural-weathering-testing-new/weathering_library/testmeth.shtml
(16009 words)
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| | Spaceflight Now | Pegasus Launch Report | The SORCE spacecraft |
| | For example, ozone is especially sensitive to changes in the Sun's ultraviolet radiation, and both observations and models show a close relationship of their concentrations to solar irradiance. | | | The wavelength coverage is primarily from 300 to 2000 nanometer range, with an additional channel to cover the 200 to 300 nm, and thereby overlap with the observations of SOLSTICE. | | | Understanding the wavelength-dependent solar variability is of primary importance for long-term climate change studies. |
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http://www.spaceflightnow.com/pegasus/sorce/030123sorce.html
(2748 words)
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| | Complex Metabolic Oscillations in Plants Forced by Harmonic Irradiance -- Nedbal and B![]() |
| | The colors show the phase shift of a given oscillation, with red approaching the phase of the exciting light from the positive side and blue from the negative side. | | | data show that the changes in irradiance do not change the central | | | abrupt change in irradiance or in CO concentration, and that |
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http://www.biophysj.org/cgi/content/full/83/4/2180
(4560 words)
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| | An Efficient Representation for Irradiance Environment Maps |
| | For rendering, the key observation is that the Lambertian BRDF behaves sufficiently closely to a low-pass filter that we need consider only the first 2 orders of spherical harmonics, i.e. | | | The key to our approach is the rapid computation of an analytic approximation to the irradiance environment map. | | | No texture-mapping is required for the irradiance with our approach. |
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http://graphics.stanford.edu/papers/envmap
(657 words)
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| | EO Study: Watching the Sun |
| | In real terms, this means total irradiance data gathered over a few decades is just beginning to scratch the surface of what we can understand about the sun’s behavior and its impact on the Earth’s climate. | | | Total solar irradiance is the light energy coming to the Earth, most being in the wavelengths from 200 to 2000 nanometers. | | | Climate models show that changes as small as 0.5 percent of full scale over a century could produce equivalents of the most extreme periods of warm or cold climate that the Earth has experienced within the period humans have lived here. |
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http://earthobservatory.nasa.gov/Study/ACRIMIII
(1033 words)
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| | solar irradiance |
| | With information about the exposition of buildings to the solar radiation lighting conditions in internal spaces can be studied, usage of energy be optimised and the risk of stress and destruction of materials by irradiance and thermal fluctuations be assessed. | | | Simulation of the irradiance taking into account the general conditions at the designated location allows an optimisation of the orientation of receiving surfaces and therewith results in a maximum energy gain. | | | Example for the mean annual irradiance in an urban area. |
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http://www.metcon-umb.de/englisch/strahlung.html
(322 words)
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| | [Arv94] |
| | The irradiance at a point on a surface due to a polyhedral source of uniform brightness has a well-known analytic formula. | | | In this paper we derive the corresponding analytic expression for the irradiance Jacobian, the derivative of the vector representation of irradiance. | | | Isolux contours are curves of constant irradiance across a surface that can be followed using a predictor-corrector method based on the irradiance Jacobian. |
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http://www.graphics.cornell.edu/pubs/1994/Arv94.html
(195 words)
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| | [No title] |
| | Taking the daily average of all the simultaneous pairs of PAR and pyranometer observations would have weighted each measurement ratio equally, even for low sun conditions that contribute negligibly to the daily insolation, and might also be influenced by the difference in response time of the two sensors. | | | The flux sensors record the instantaneous irradiance at 1-minute intervals. | | | The ratio of PAR flux to total solar flux (PAR fraction) was examined for all atmospheric conditions during 1999, and the observed dependence of this parameter on column water vapor and smoke AOT was quantified. |
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http://aeronet.gsfc.nasa.gov/TXT/2001JD000428.txt
(2254 words)
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| | VRay.info |
| | Your irradiance map settings are your own to choose. | | | However there is no need to create new samples every frame. | | | Final Steps: When your irradiance map pass is finished, reset the nth frame to 1 and put your AA back to the way you want it. |
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http://www.vray.info/entryprint.asp?entryID=94
(477 words)
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| | Practical Course: Photovoltaic Energy Systems |
| | In our experiment we use a pyranometer because it gives us a spectral independent value of the irradiance while the slow reaction time is less important for our purpose. | | | In our experiment we us a so called star-pyranometer which has got black-and-white areas on the absorber area which are thermally isolated from each other, in order to get temperature reference points for the thermocouple. | | | The position with the lowest irradiance is taken as the reference point. |
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http://emsolar.ee.tu-berlin.de/lehre/english/pv1/index.html
(3255 words)
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| | Acrimsat Comes Online To Measure On The Solar Irradiance |
| | Researchers theorize that as much as 25 percent of the anticipated global warming of Earth may be solar in origin. | | | Small changes in total solar irradiance by the Sun over a century or more may cause significant climate changes on Earth. | | | Acrimsat is part of a multi-decade effort to understand variations in the Sun's output and resulting effects on Earth. |
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http://www.spacedaily.com/news/eo-00g.html
(357 words)
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| | Science Objectives |
| | To use this knowledge to estimate past and future solar behavior and climate response. | | | Improve our understanding of how and why the variability occurs at the Sun and how the variable irradiance affects our atmosphere and climate. | | | To use the solar/stellar comparison technique to relate the solar irradiance to the ensemble average flux from a number of bright, early-type stars (same stars used by the UARS SOLSTICE program). |
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http://lasp.colorado.edu/sorce/science_objectives.html
(253 words)
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| | Astron. Astrophys. 335, 709-718 (1998) |
| | The detailed flux spectrum for each component is employed. | | | Since it also successfully reproduces changes in the UV spectral irradiance, irradiance variations and observed variations of the faculae-to-spots filling factor ratio since 1978, our model supports earlier suggestions that a large part of the solar irradiance variations is caused by magnetic fields at the solar surface. | | | Our results suggest that this effect can explain only a small part of the discrepancy. |
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http://aa.springer.de/papers/8335002/2300709/small.htm
(274 words)
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| | Big Bear Solar Observatory - CaII K-Line Paper |
| | Reproduction of the Lyman-alpha Irradiance Variability from Analysis of Full-Disk Images In the CaII K-line | | | Because of the long-term significance of these observations, we continued a low-level program of simply recording and digitizing the images (Marquette, 1992) without analysis. | | | 2) between the UARS SOLSTICE Ly-alpha irradiance (London et al., 1993) and the BBSO index shows a correlation coefficient of 0.9 for the whole period, 1991 to 1994, with no phase lag. |
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http://www.bbso.njit.edu/Research/Cak/cak_paper.html
(1389 words)
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| | Penpan |
| | There seems no other problem in applying Penman's equation in arid circumstances. | | | The resulting equation for the monthly mean pan-evaporation rate (the so-called ‘Penpan’ formula) includes an estimate of the solar irradiance, which may be obtained from the extra-terrestrial radiation and the cloudiness, derived from rainfall figures. | | | Altering Eqn 1 to give the pan-evaporation rate Ep involves the geometry of the raised, circular pan, which affects its solar irradiance and advective heat transfer. |
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http://www-das.uwyo.edu/~geerts/cwx/penpan.html
(6355 words)
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| | Publikationen |
| | Evaluation of the long-term experiments in environmental sciences carried out at the Jungfraujoch research station, Grindelwald Switzerland, 24.-26.6.1999 | | | D photolysis frequencies retrieved from spectral measurements of irradiance at Thessaloniki, Greece. | | | Webb A.R., Kift R., Thiel S., Blumthaler M.: An empirical method for the conversion of spectral UV irradiance measurements to actinic flux data. |
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http://www.uibk.ac.at/c/c5/c502/publikat2.html
(7460 words)
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| | [No title] |
| | biology and medical science for irradiation of organisms in solaria under the condition found in nature. | | | During the past decade a vast amount of new data has become available both through modernized measurement techniques as well as improved modelling and parameterization methods. | | | It is also desirable that the number of spectral bands for which integrated solar irradiance levels are given, should be increased, especially in the ultraviolet region where the degradation coefficient for organic material increases nearly exponentially with a decrease in wavelength. |
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http://www.cie.co.at/publ/abst/85-89.html
(441 words)
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| | DIALOG Dissertation Abstracts |
| | In contrast, effects of ozone depletion which only increases UVB irradiance, will not be counteracted by an acclimation to the enhanced UVB irradiance. | | | Under both conditions, the total effect induced by enhanced UVB irradiance was mainly related to the applied maximum incident irradiance not to the applied cumulative dose. | | | Under natural conditions vertical mixing will induce photoacclimation to low irradiance by subjecting phytoplankton to a low mean UVA/PAR irradiance. |
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http://www.aslo.org/phd/dialog/199911-5.html
(421 words)
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| | Irradiance - encyclopedia article about Irradiance. |
| | Irradiance, radiant emittance, and radiant exitance are radiometry terms for the power of electromagnetic radiation at a surface, per unit area. | | | Note that this is quite distinct from the meaning of intensity in other areas of physics, and the latter definition is sometimes used in optics as well, where irradiance or radiant exitance would be the preferred radiometric term. | | | This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. |
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http://encyclopedia.thefreedictionary.com/Irradiance
(1873 words)
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| | [Gre96] |
| | The irradiance volume method is tested within several situations in which the use of traditional global illumination methods is impractical, and is shown to provide good performance. | | | A theoretical basis for the irradiance volume is discussed and the methods and issues involved with building the volume are described. | | | Although irradiance is traditionally computed only for surfaces, its definition can be naturally extended to all points and directions in space. |
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http://www.graphics.cornell.edu/pubs/1996/Gre96.html
(108 words)
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| | Ocean Physics Laboratory, University of California Santa Barbara |
| | (23) Siegel, D.A., and T.D. Dickey, 1988, Characterization of downwelling spectral irradiance fluctuations, Proc. | | | (4) Simpson, J.J., and T.D. Dickey, 1981, The relationship between downward irradiance and upper ocean structure, J. Phys. | | | (43) Stramska, M. and T.D. Dickey, 1992, Short-term variations of the bio-optical properties of the ocean in response to cloud-induced irradiance fluctuations, J. Geophys. |
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http://www.opl.ucsb.edu/tommy/publications.html
(4403 words)
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| | STUDY OF SOLAR IRRADIANCE VARIATIONS |
| | The time interval 1996 through 1998 offers an opportunity to investigate the sources of solar irradiance variations and to relate them to structural changes in the solar interior, if they are not strictly superficial as some theory predicts (fig.1) | | | Irradiance and magnetic field measurements from the VIRGO and MDI instruments on board the Solar and Heliospheric Observatory (SOHO) are being analyzed for the study of magnetic activity influence on the solar radiation emission. | | | The main activity of the group is the investigation of the irradiance properties of individual sources in the solar photosphere that contribute to solar irradiance changes: sunspots, pores, faculae and network. |
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http://www.am.ub.es/~blai/sol_constant_UB.html
(459 words)
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| | Irradiance |
| | Irradiance, in physics, is a specific measure, viz., the density of radiant flux incident on a given area, typically measured as a unit of power per unit area (for example watts per square meter). | | | Molectron Detector, Inc. Specializes in calibrated instruments and detectors for measuring laser energy, laser power, rep rate, irradiance and other vital statistics. | | | Measurement and Instrumentation Data Center (MIDC) Provides links to irradiance and meterological data from several stations in the Unites States. |
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http://www.serebella.com/encyclopedia/article-Irradiance.html
(146 words)
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| | irradiance measurement |
| | Irradiance measurements can be done in the UV/VIS as well in the VIS/NIR range. | | | Spectral Irradiance measurements can be done in different setups and wavelength ranges, like with fiber optic cosine corrector or integrating sphere. | | | A typical setup for irradiance measurement is given below. |
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http://www.avantes.com/Applications/irradiance.htm
(153 words)
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| | [No title] |
| | Inference of Solar Irradiance Variability from Terrestrial Temperaturebreak Changes 1880-1993: An Astrophysical Application of the Sun-Climate Connection | | | Information can be inferred on the timing and amplitude of solar total irradiance changes over 1880-1993 by simulating the global terrestrial surface temperature changes produced by these irradiance changes and comparing them with observed temperatures. | | | Optimized cases imply total irradiance changes during 1880-1993 in the range of 0.18% - 0.77%. |
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http://cfa-www.harvard.edu/ep/preprint/mayjun96/4344.html
(277 words)
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| | ETHZ IfA: Past Solar Irradiance Variations |
| | The magnitude of the contribution of solar luminosity variations to global change, however, has been the subject of considerable debate. | | | One of the unknown boundary conditions for models of the evolution of the Earth's climate is the magnitude of the variation of the solar irradiance (i.e. | | | Such an extension of the range of solar irradiance variations puts the hypothesis of a direct connection to terrestrial climate on a much firmer footing. |
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http://www.astro.phys.ethz.ch/research/fligge/paleo_nf.html
(364 words)
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| | AvaSoft Application Software - Irradiance |
| | The radiated optical energy can be correlated with human vision (photometry) as defined in the CIE to obtain a spectral luminous efficiency function to characterize the vision of an average human observer. | | | An other option is to have your Avantes spectrometer system calibrated in our irradiance calibration lab, so there is no need to have an additional calibrated light source. | | | Related photometric quantities are luminous flux (lumen) or illuminance (lux or lumen per m²). |
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http://www.avantes.com/Software/AvaSoft%20Irr.htm
(449 words)
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| | Irradiance |
| | Irradiance, in physics, is the density of radiant flux incident on a given area, typically measured as a unit of power per unit area (for example watts per square metre). |
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http://www.worldhistory.com/wiki/i/irradiance.htm
(109 words)
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| | UO SRML: Calculating diffuse irradiance |
| | This is true instantaneously, but over longer time intervals this becomes an approximation because the beam radiation changes in a systematic way over the day. | | | Diffuse irradiance refers to all the solar radiation coming from the sky except for solar radiation coming directly from the sun and the circumsolar irradiance within approximately three degrees of the sun. | | | Measurement of diffuse radiation is difficult because one needs to shade the pyranometer from the direct normal and the circumsolar irradiance. |
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http://solardat.uoregon.edu/DiffuseCalculation.html
(534 words)
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| | EO Library: ACRIMSAT Page 2 |
| | Systematic changes in irradiance as little as 0.25% per century can cause the complete range of climate variations that have occurred in the past, ranging from ice ages to global tropical conditions. | | | Scientists theorize that as much as 25% of the 20th century anticipated global warming of the Earth may be due to changes in the sun’s energy output. | | | For example, scientists believe the "Little Ice Age" that occured in Europe in the late 17th century could have been related to the minimum in sunspot activity (and a correlated minimum in total solar irradiance) that occured during the same period. |
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http://earthobservatory.nasa.gov/Library/ACRIMSAT/acrimsat_2.html
(223 words)
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| | Irradiance Gradients |
| | The information from a hemispherical sampling of the luminous environment is interpreted in a new way to predict the change in irradiance as a function of position and surface orientation. | | | This result is achieved through better utilization of ray samples rather than additional samples or alternate sampling strategies. | | | A new method for improving the accuracy of a diffuse interreflection calculation is introduced in a ray tracing context. |
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http://radsite.lbl.gov/radiance/papers/erw92/paper.html
(177 words)
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| | Irradiance |
| | Irradiance is the successor to Ascension Technology and my work at MIT. | | | Irradiance will develop and market innovative PV systems and components, develop new high profile renewable energy projects, and new information products and services to foster awareness of energy consumption, its environmental consequences, and emerging renewable energy alternatives, and develop new instrumentation products and services that will expedite the marketplace for solar power. | | | I launched this new enterprise, Irradiance in May 2002. |
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http://www.irradiance.com
(169 words)
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| | The North American/International Alliance of Tanning Salon Owners |
| | Interested in seeing the difference that an absorption filter makes to a xenon irradiance source? | | | As you can see, there are UVC (200 nm - 280 nm) photons being emitted by the unfiltered xenon irradiance source but not in the photons passing through the absorption filter. | | | Click on the link above to view (and print) a graph showing an unfiltered xenon irradiance source vs the same irradiance source that is filtered. |
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http://www.naatso.org/NewsView.cfm?pkArticleID=135&S=A
(220 words)
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| | Current Projects |
| | Their use in a series of Active Cavity Radiometer Irradiance Monitor (ACRIM) space flight experiments has provided the most precise and traceable component of the TSI database during 87 % of its 26+ year history. | | | Evidence from TSI monitoring, cosmogenic isotope analyses and correlative climate data indicate that variability of the TSI has been a significant climate forcing in the past. | | | The characteristics and variability of the radiation emitted by the Sun are of overriding importance to all life on Earth. |
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http://www.acrim.com
(728 words)
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| | DIALOG Dissertation Abstracts |
| | Combined, these results demonstrate the utility of photosystem II properties as a function of background irradiance in describing the irradiance structure of photosynthetic efficiency, but also demonstrate the limitations of fluorescence techniques. | | | These results demonstrate that under a variety of environmental situations characteristic of natural oceanic variability, photosystem II properties describe well the relative structure of photosynthesis-irradiance curves. | | | However, other processes not associated with photosystem II (or characterized by fluorescence) and unique to each environmental situation can significantly impact the magnitude of photosynthetic rates and efficiency. |
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http://www.aslo.org/phd/dialog/200012-24.html
(307 words)
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| | SRRL: Pictures of the Solar Radiation Research Lab and Instrumentation |
| | Aerial view of the 96 foot by 16 foot instrument deck at SRRL. | | | An all-sky photograph taken at SRRL under partly-cloudy conditions. | | | Previous research support included the irradiance distributions on vertical surfaces for model evaluations (pyranometers mounted on and behind artificial horizon). |
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http://www.nrel.gov/srrl/pictures
(674 words)
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| | Ground Calibration |
| | The SOlar Stellar Irradiance Comparison Experiment (SOLSTICE) is one of four solar irradiance measurement experiments that was launched as part of the Solar Radiation and Climate Experiment (SORCE) on January 25, 2003. | | | This approach provides an accurate monitor of instrument in-flight performance and provides a basis for solar-stellar irradiance comparison for future generations. | | | SORCE SOLSTICE is a follow-on to the very successful SOLSTICE launched aboard the Upper Atmospheric Research Satellite (UARS) in 1991 [Rottman et al., 1993]. |
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http://lasp.colorado.edu/sorce/solstice.html
(103 words)
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| | Instrument Systems - Irradiance |
| | for a point light source is derived from the above formula for irradiance E |
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http://www.lightmeasurement.com/irradiance.htm
(33 words)
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| | NASA GISS: Research News: NASA Study Finds Increasing Solar Trend That Can Change Climate |
| | Although the inferred increase of solar irradiance in 24 years, about 0.1 percent, is not enough to cause notable climate change, the trend would be important if maintained for a century or more. | | | The sunspot numbers are representative of the general level of solar activity. | | | This amount of missing irradiance is insignificant compared to the Sun's total energy output but equivalent to all that man produces and consumes in a year. |
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http://www.giss.nasa.gov/research/stories/20030320
(1184 words)
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| | Solar Spectra: Air Mass Zero |
| | The integrated spectral irradiance has been made to conform to the value of the solar constant accepted by the space community; which is 1366.1 W/m | | | This spectral distribution was constructed in 1985, based on the following references: | | | The composite spectral irradiance data were then scaled by a factor of 0.99745 to force the integrated total irradiance equal to the solar constant. |
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http://rredc.nrel.gov/solar/spectra/am0
(452 words)
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| | VRay.info |
| | Needless to say a static irradiance map goes completely out of wack if any object or texture is animated so it is for pure static scenes only. | | | A: Yes and No, you can make an irradiance map that covers all your cameras, but you cant do it in one go, there are severeal different ways of doing this: | | | Render this camera with the same options as in suggestion #1 and you end up with a completely view independent irradiance map. |
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http://www.vray.info/entryprint.asp?entryID=92
(143 words)
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