Problems to be solved
Aerosols affect life on earth in several ways. They play an important role in the climate system; the effect of aerosols on the global climate system is one of the major uncertainties of present climate predictions. They play a major role in atmospheric chemistry and hence affect the concentrations of other potentially harmful atmospheric constituents, e.g. ozone. They are an important controlling factor for the radiation budget, in particular in the UV-B part of the spectrum. At ground level, they can be harmful, even toxic, to man, animals, and plants. Because of these adverse effects that aerosols can have on human life, it is necessary to achieve an advanced understanding of the processes that generate, redistribute, and remove aerosols in the atmosphere. A quantitative dataset describing the aerosol vertical, horizontal, and temporal distribution, including its variability on a continental scale, is necessary. Such a dataset could be used to validate and improve models that predict the future state of the atmosphere and its dependence on different scenarios describing economic development, including those actions taken to preserve the quality of the environment. No suitable data set for this purpose presently exists.
Scientific objectives and approach
EARLINET will establish a quantitative comprehensive statistical database of the horizontal, vertical, and temporal distribution of aerosols on a continental scale. The goal is to provide aerosol data with unbiased sampling, for important selected processes, and air-mass history, together with comprehensive analyses of these data. The objectives will be reached by implementing a network of 21 stations distributed over most of Europe, using advanced quantitative laser remote sensing to directly measure the vertical distribution of aerosols, supported by a suite of more conventional observations. Special care will be taken to assure data quality, including intercomparisons at instrument and evaluation levels. A major part of the measurements will be performed according to a fixed schedule to provide an unbiased statistically significant data set. Additional measurements will be performed to specifically address important processes that are localised either in space or time. Back-trajectories derived from operational weather prediction models will be used to characterise the history of the observed air parcels, accounting explicitly for the vertical distribution.
EARLINET will make a major contribution to the quantification of anthropogenic and biogenic emissions and concentrations of aerosol, quantification of their budgets, radiative properties and prediction of future trends. It will also further the understanding of physical and chemical processes related to these species, their long-range transport and deposition, and the interaction of aerosols with clouds. The project will also make an important contribution to the improved model treatment of physical and biospheric processes, in particular clouds and aerosols. The data to be collected will be used to improve the quality of a number of satellite retrieval systems that are affected by the presence of aerosols, and will provide the necessary basis for future satellite missions that employ laser remote sensing. EARLINET will provide information about transboundary transport of aerosols that can also be used as a tracer for other substances in the planning of pollution abatements strategies. Co-operation within the network will lead to a very efficient transfer of know-how in two important areas: advanced remote sensing using high-tech instruments, and the application of these techniques to address complex environmental problems. It will be a very effective training area for young scientists, both from well-developed and less-developed countries, providing equal opportunities to use the common data.
Funding SchemeCSC - Cost-sharing contracts
05-622 Belsk Duzy
5001 Nova Gorica
SY23 3BZ Aberystwyth