This book is the result of a working group sponsored by ISSI in Bern, which was initially created to study possible ways to calibrate a Far Ultraviolet (FUV) instrument after launch. In most cases, ultraviolet instruments are well calibrated on the ground, but unfortunately, optics and detectors in the FUV are very sensitive to contaminants and it is very challenging to prevent contamination before and during the test and launch sequences of a space mission. Therefore, ground calibrations need to be confirmed after launch and it is necessary to keep track of the temporal evolution of the sensitivity of the instrument during the mission.
The studies presented here cover various fields of FUV spectroscopy, including a catalog of stellar spectra, datasets of Moon Irradiance, observations of comets and measurements of the interplanetary background. Detailed modelling of the interplanetary background is presented as well. This work also includes comparisons of older datasets with current ones. This raises the question of the consistency of the existing datasets. Previous experiments have been calibrated independently and comparison of the datasets may lead to inconsistencies. The authors have tried to check that possibility in the datasets and when relevant suggest a correction factor for the corresponding data."

ESA's Venus Express Mission has monitored Venus since April 2006, and scientists worldwide have used mathematical models to investigate its atmosphere and model its circulation. This book summarizes recent work to explore and understand the climate of the planet through a research program under the auspices of the International Space Science Institute (ISSI) in Bern, Switzerland. Some of the unique elements that are discussed are the anomalies with Venus' surface temperature (the huge greenhouse effect causes the surface to rise to 460 DegreesC, without which would plummet as low as -40 DegreesC), its unusual lack of solar radiation (despite being closer to the Sun, Venus receives less solar radiation than Earth due to its dense cloud cover reflecting 76% back) and the juxtaposition of its atmosphere and planetary rotation (wind speeds can climb up to 200 m/s, much faster than Venus' sidereal day of 243 Earth-days).

This book provides a comprehensive presentation of Earth s energy flows and their consequences for the climate. The Earth s climate as well as planetary climates in general, are broadly controlled by three fundamental parameters: the solar irradiance, the planetary albedo and the planetary emissivity. Space measurements indicate that these three quantities are remarkably stable. A minor decrease inplanetary emissivity is consistent with theoretical calculations. This is due to the ongoing increase of atmospheric greenhouse gases making the atmosphere more opaque to long wave terrestrial radiation. As a consequence radiation processes are slightly out of balance as less heat is leaving the Earth in the form of thermal radiation than the incoming amount of heat from the sun. Present space-based systems cannot yet satisfactorily measure this imbalance, but the effect can be inferred from the measurements of the increase of heat in the oceans. Minor amounts of heat are also used to melt ice and to warm the atmosphere and the surface of the Earth.
The book brings to fore the complexity of feedback processes of the Earth s climate system and in particular the way clouds and aerosols affect the energy balance both directly and indirectly through feed-back loops driven by the dynamics of atmospheric, ocean and land surface processes. The book highlights recent scientific progress as well as remaining challenges.
Previously published in Surveys in Geophysics, Volume 33, Nos. 3-4, 2012"

ESA's Venus Express Mission has monitored Venus since April 2006, and scientists worldwide have used mathematical models to investigate its atmosphere and model its circulation. This book summarizes recent work to explore and understand the climate of the planet through a research program under the auspices of the International Space Science Institute (ISSI) in Bern, Switzerland. Some of the unique elements that are discussed are the anomalies with Venus' surface temperature (the huge greenhouse effect causes the surface to rise to 460 DegreesC, without which would plummet as low as -40 DegreesC), its unusual lack of solar radiation (despite being closer to the Sun, Venus receives less solar radiation than Earth due to its dense cloud cover reflecting 76% back) and the juxtaposition of its atmosphere and planetary rotation (wind speeds can climb up to 200 m/s, much faster than Venus' sidereal day of 243 Earth-days).

This book is the result of a working group sponsored by ISSI in Bern, which was initially created to study possible ways to calibrate a Far Ultraviolet (FUV) instrument after launch. In most cases, ultraviolet instruments are well calibrated on the ground, but unfortunately, optics and detectors in the FUV are very sensitive to contaminants and it is very challenging to prevent contamination before and during the test and launch sequences of a space mission. Therefore, ground calibrations need to be confirmed after launch and it is necessary to keep track of the temporal evolution of the sensitivity of the instrument during the mission. The studies presented here cover various fields of FUV spectroscopy, including a catalog of stellar spectra, datasets of Moon Irradiance, observations of comets and measurements of the interplanetary background. Detailed modelling of the interplanetary background is presented as well. This work also includes comparisons of older datasets with current ones. This raises the question of the consistency of the existing datasets. Previous experiments have been calibrated independently and comparison of the datasets may lead to inconsistencies. The authors have tried to check that possibility in the datasets and when relevant suggest a correction factor for the corresponding data.