The winner of the 17th Professor Vilho Vaisala Award at WMO is Dr. Rolf Philipona from Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center (PMOD/WRC), Switzerland. Dr. Philipona received the award for his paper entitled “Sky-scanning Radiometer for Absolute Measurements of Atmospheric long-wave Radiation”.
The 17th Professor Vilho Vaisala Award (2002) was presented on 27 January 2003 at the WMO headquarters in Geneva by the WMO General Secretary G. O. P. Obasi. The winning research paper “Sky-scanning Radiometer for Absolute Measurements of Atmospheric long-wave Radiation” was published in Applied Optics, Vol. 40, No. 15, 2376-2383, 2001.
Dr. Rolf Philipona was recognized for his scientific work at PMOD/WRC on developing the methods and technology for measuring atmospheric long-wave radiation. Atmospheric long-wave radiation is directly related to the greenhouse effect, which makes it an interesting parameter for monitoring climate change. However, earlier long-wave radiation measurement instruments used in the field, such as pyrgeometers, have suffered from uncertainties, and have not met the criteria for accurate measurement.
To solve pyrgeometer calibration problems, a new blackbody calibration apparatus was built at PMOD/WRC. As uncertainties related to thermal effects and inadequate spectral transmission still remained, a new absolute sky-scanning radiometer (ASR) was developed. The calibration of the ASR is based on a reference blackbody source. The ASR offers absolute measurement of atmospheric long-wave radiation, and is now suggested to become a future reference for pyrgeometer calibration. To avoid thermal and spectral transmission effects, the pyroelectric detector of the ASR has no window. A narrow viewing angle is used which prevents errors related to the cosine effects and Gaussian quadrature is used to integrate over a fixed number of measuring points in the sky. The performance of ASR was proven in two international comparisons of pyrgeometers and absolute sky-scanning radiometers (Oklahoma, 1999 and Alaska 2001).
Designed to encourage research programs
The Professor Vilho Vaisala Award was established in 1985 and is administrated by the World Meteorological Organization (WMO). It is awarded to encourage and stimulate interest in important research supportive of WMO’s programs, in the field of meteorological and climatic observation methods and instruments.
The award cermony was held at WMO headquarters in Geneva. WMO General Secretary G. O. P. Obasi at the left, Dr. Rolf Philipona in the middle, Vaisala President and CEO Pekka Ketonen on the right.