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Biological monitoring of solar UV radiation using spore dosimeters has been undertaken since the year 1999 at more than 20 sites in Asia, Europe and South America. The monthly-cumulative data to the end of the year 2004 have been presented before. In this paper, successive data to the end of the year 2007 are compiled and the trends and correlation analyses with yearly and monthly average amounts of columnar ozone are presented. Mean yearly doses at 10 northern and 6 southern hemisphere sites exhibited exponential latitudinal gradients with similar slopes indicating a doubling of the dose with the decline of about 14 degrees. Among 12 sites where continual data for more than 6 years were available, increasing trends in yearly UV doses were observed at 11 sites. At one European (Brussels), two tropical Asian (Padang and Denpasar), and two South American (São Martinho and Punta Arenas) sites, decreasing trends of ozone amounts were noted, whereas at the remaining 6 sites (five sites in Japan and Thessaloniki), increasing trends of the UV doses were observed without notable changes, or with an increase at one site (Kiyotake), of the average ozone amounts. At one site (Taipei), the UV doses and the ozone amounts stayed constant. In the monsoon areas, climatic variations and changes, particularly in the extent of cloudiness and frequency of rainfall in summer months, might have been largely responsible for the trends of the UV doses. However, even at these sites, the decreases in the ozone amounts in summer months were frequently observed and might have contributed to the increasing trends of the UV doses. Since each region and locality is unique in climatic and atmospheric conditions, it is not easy to generalize the global trends. However, at many sites involved in this monitoring project, the increases in the biological UV doses during this period seemed to be linked to the decreases in the ozone amounts. [ABSTRACT FROM AUTHOR]

Climatic hazards such as floods and droughts have always been a primary matter of concern for human populations. Severe floods damage settlements, transport networks, and arable land. Although devastating droughts are harmful primarily for agriculture and terrestrial ecosystems, they can also lead to local water supply shortages. Despite significant achievements in science and technology and success stories in environmental management in the 20th century, people still continue to suffer the consequences of climate hazards worldwide. This paper provides an overview of existing practices for coping with floods and droughts, compares strategies in different river basins, and outlines the areas that need improvement. First, the existing protection measures and response strategies against floods and droughts are briefly described. An overview is given of expected climate change and existing coping strategies for floods and droughts in seven case study basins. Four of the basins, namely the Elbe, Guadiana, Rhine, and Tisza, are located in Europe the Nile and the Orange are in Africa; and the Amudarya is in Central Asia. Analysis of the coping strategies shows that structural measures exist in all seven river basins, but that nonstructural measures are generally not very extensive and/or advanced. Finally, the success stories in dealing with climatic hazards and lessons learned, taken partly from the seven case study basins and partly from literature, are summarized. [ABSTRACT FROM AUTHOR]

Understanding the climate change processes requires application of special methodologies for revealing a ground surface temperature history (GSTH). It was proved by different authors that the GSTH may be determined on the basis of analysis of the temperature field observed in short boreholes. In this paper, the authors analyze four mathematical models describing the GSTH: (1) sudden change, (2) linear increase, (3) square root of time increase and (4) exponential increase. Fifteen borehole temperature profiles from Europe, Asia and North America were selected in three groups based on their geographical proximity. After careful analysis of temperature-depth profiles in these boreholes it was found out that two models (linear increase and square root of time increase) provide the best fit with field data. The calculated warming rates in the 20th century were compared with those obtained by a few parameters estimation (FPE) technique. [ABSTRACT FROM AUTHOR]