Université de Fribourg

L'ambroisie : analyse statistique et modélisation numérique de sa trajectoire aérobiologique

Goyette-Pernot, Joëlle ; Beniston, Martin (Dir.)

Thèse de doctorat : Université de Fribourg, 2006 ; no 1530.

Allergic rhinitis as well as associated costs are constantly increasing, affecting a proportion always larger of the population across the world. Ragweed is a source of pollen well known for its high allergenic properties. Characterized by heavy emissions of the pollen in the air from August to October of each year, its allergenic potential is greatly enhanced. This study deals with the problems...

Université de Fribourg

Relationship between hailfall intensity and hail damage on ground, determined by radar and lightning observations

Hohl, Roman Marco ; Beniston, Martin (Dir.)

Thèse de doctorat : Université de Fribourg, 2001 ; no 1357.

Weather radars are now available in many countries for operational observations and measurements of hailstorms and provide detailed information on the formation and structure of severe thunderstorms. Much research has been devoted to the quantitative measurement of hailfalls and the nowcasting of hail-bearing thunderstorms which is of interest for national weather services and airports (warning),...

Université de Fribourg

Extracting quantitative sub-pixel heterogeneity information from optical remote sensing data

Widlowski, Jean-Luc ; Beniston, Martin (Dir.)

Thèse de doctorat : Université de Fribourg, 2001 ; no 1358.

This work describes two approaches for the extraction of quantitative information on the degree of surface heterogeneity at the subpixel scale of optical remote sensing data. The first approach is a look-up-table based inversion scheme, where the spectral reflectances of realistically modelled three-dimensional vegetation canopies are pre-computed for a variety of atmospheric optical depths, and...

Université de Fribourg

20th century minimum and maximum temperature variations analysed on a regional scale in Switzerland : statistical analyses of observational data

Jungo, Patricia ; Beniston, Martin (Dir.) ; Collet, Claude (Codir.) ; Frei, Christoph (Codir.) ; Wanner, Heinz (Codir.)

Thèse de doctorat : Université de Fribourg, 2001 ; no 1365.

The major aim of this study is to describe in a detailed manner the 20th century minimum and maximum temperature variations in Switzerland and to assess whether the magnitude of the secular warming and its interannual to interdecadal fluctuations show common seasonal patterns in different climatological regions. In a first step different climatological regions could successfully be established...