The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Laurent Vuilleumier - One of the best experts on this subject based on the ideXlab platform.
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trend analysis of surface cloud free downwelling Long Wave Radiation from four swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
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Trend analysis of surface cloud‐free downwelling Long‐Wave Radiation from four Swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
Stefan Wacker - One of the best experts on this subject based on the ideXlab platform.
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trend analysis of surface cloud free downwelling Long Wave Radiation from four swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
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Trend analysis of surface cloud‐free downwelling Long‐Wave Radiation from four Swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
Ralf Toumi - One of the best experts on this subject based on the ideXlab platform.
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the correlation between tropical total ozone and outgoing Long Wave Radiation
Quarterly Journal of the Royal Meteorological Society, 2001Co-Authors: Victoria Williams, Ralf ToumiAbstract:Interannual variations in tropical column ozone, as observed by the Total Ozone Mapping Spectrometer, are analysed for the period 1979-94 using linear regression to extract signals related to the solar cycle, quasi-biennial oscillation, and El Nino Southern Oscillation (ENSO). Using time series of outgoing Long-Wave Radiation (OLR) as a proxy for ENSO variations, rather than the widely used Southern Oscillation Index is found to improve the fit to observed ozone. The variability in the ozone and OLR datasets is investigated using empirical orthogonal function analysis. The most strongly correlated OLR and ozone modes exhibit ENSO-like variability.
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The correlation between tropical total ozone and outgoing Long‐Wave Radiation
Quarterly Journal of the Royal Meteorological Society, 2001Co-Authors: Victoria Williams, Ralf ToumiAbstract:Interannual variations in tropical column ozone, as observed by the Total Ozone Mapping Spectrometer, are analysed for the period 1979-94 using linear regression to extract signals related to the solar cycle, quasi-biennial oscillation, and El Nino Southern Oscillation (ENSO). Using time series of outgoing Long-Wave Radiation (OLR) as a proxy for ENSO variations, rather than the widely used Southern Oscillation Index is found to improve the fit to observed ozone. The variability in the ozone and OLR datasets is investigated using empirical orthogonal function analysis. The most strongly correlated OLR and ozone modes exhibit ENSO-like variability.
Julian Gröbner - One of the best experts on this subject based on the ideXlab platform.
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trend analysis of surface cloud free downwelling Long Wave Radiation from four swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
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Trend analysis of surface cloud‐free downwelling Long‐Wave Radiation from four Swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
Klemens Hocke - One of the best experts on this subject based on the ideXlab platform.
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trend analysis of surface cloud free downwelling Long Wave Radiation from four swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
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Trend analysis of surface cloud‐free downwelling Long‐Wave Radiation from four Swiss sites
Journal of Geophysical Research, 2011Co-Authors: Stefan Wacker, Julian Gröbner, Klemens Hocke, Niklaus Kämpfer, Laurent VuilleumierAbstract:[1] We present a trend analysis of surface cloud-free downwelling Long-Wave Radiation provided by pyrgeometer measurements of four stations of the Alpine surface Radiation budget network in Switzerland. The stations cover an altitude range between 370 and 3580 meters above sea level. Cloud-free downwelling Long-Wave Radiation, screen-level temperature, and relative humidity were selected from 10 min measurements, and monthly means were calculated. We performed two distinct trend analyses: the annual overall trend was determined applying least squares fitting, whereas nonparametric statistical methods were used to calculate the monthly trends. The cloud-free downwelling Long-Wave Radiation time series shows a consistent and significant increase of 3.5 W m−2 per decade in the last 12 years at all four stations. The monthly trend analysis of the downwelling Long-Wave Radiation revealed trend estimates exceeding the overall trend by a factor of 4 and partly with opposite signs. The monthly trends of the downwelling Long-Wave Radiation are in agreement with the trends observed in screen-level temperature and specific humidity which have been determined using the same statistical methods. By applying a parameterization of cloud-free downwelling Long-Wave Radiation, we quantitatively inferred the causes for the observed cloud-free trends. More than 50% of the downwelling Long-Wave Radiation trends can be explained with the observed variations of temperature and humidity. There is some indication that the radiative effect of high-level clouds has changed and considerably contributed to the downwelling Long-Wave Radiation trends that are not induced by screen-level temperature and humidity.
