Development and validation of tools for the implementation of european air quality policy in Germany (Project VALIUM)
In the framework of the German Atmospheric Research Program AFO-2000 a system of consistent coupled numerical models has been developed. The purpose of the model system is to serve as a tool for the execution of European urban air quality regulations. A consortium with the acronym VALIUM was formed, which consisted of German research institutes, environmental consultancies and an environmental agency. A substantial part of the VALIUM program was devoted to the generation of a set of high quality data for the validation of the numerical model system. The validation data are based on a combination of field studies, tracer experiments and corresponding wind tunnel experiments. The field experiments were carried out inside and around a street canyon in a city district of Hanover/Germany. After a brief introduction to the VALIUM project a summary of the main results will be given.
Overview of the European project FUMAPEX
The quality of the urban air pollution forecast crit- ically depends on the mapping of emissions, the urban air pollution models, and the meteorological data. The quality of the meteorological data should be largely enhanced by us- ing downscaled data from advanced numerical weather pre- diction models. These different topics, as well as the ap- plication of population exposure models, have traditionally been treated in distinct scientific communities whose exper- tise needs to be combined to enhance the possibilities of fore- casting air pollution episodes in European cities. For this purpose the EU project "Integrated Systems for Forecasting Urban Meteorology, Air Pollution and Population Exposure" (FUMAPEX) (http://fumapex.dmi.dk), involving 22 organi- zations from 10 European countries, was initiated. The main objectives of the project are the improvement of meteorolog- ical forecasts for urban areas, the connection of numerical weather prediction models to urban air pollution and popu- lation exposure models, the building of improved Urban Air Quality Information and Forecasting Systems, and their ap- plication in cities in various European climates. This paper overviews the project items and first two-years results, it is an introduction to the whole ACP issue. ity (UAQ) is still considered as a problem especially during short-term episodes that occur during adverse meteorologi- cal conditions, causing exceedances of short-term air quality standards (e.g. during episodes in 1995 in London NO2 ex- ceeded 400 ppb). Short-term pollution episodes are presently one of the major concerns for the protection of human health in urban environment. This has lead to the introduction of EU Air Quality Directives to abate adverse health effects of air pollution to European citizens. The new EU air quality standards to be implemented by 2005 and 2010 will focus even more on episode prevention and forecasting. Moreover, a reliable urban scale forecast of air flows and meteorolog- ical fields is of primary support for urban emergency man- agement systems for accidental toxic releases, fires, or even chemical, radioactive, or biological substance releases due to terrorist actions, the potential risk of which has been recently emerged.
LAND DEGRADATION IN THE DEVELOPING WORLD: ISSUES AND POLICY OPTIONS FOR 2020
Land degradation takes a number of forms, including depletion of soil nutrients, salinization, agrochemical pollution, soil erosion, vegetative degradation as a result of overgrazing, and the cutting of forests for farmland. All of these types of degradation cause a decline in the productive capacity of the land, reducing potential yields. Farmers may need to use more inputs such as fertilizer or manure in order to maintain yields, or they may temporarily or permanently abandon some plots. Degradation may also induce farmers to convert land to lower-value uses. For example, farmers may plant cassava, which demands few nutrients, instead of maize, or convert cropland to grazing land.