Because of their sensitivity remote mountain lakes are not only vulnerable to environmental change they are also excellent sensors of change, and their high quality sediment records can be used to infer the speed, direction and biological impact of changing air quality and climate. This proposal builds on the success of the EU funded AL:PE projects (Acidification of Remote Mountain Lakes: Palaeolimnology and Ecology; Remote Mountain Lakes as Indicators of Air Pollution and Climate Change), which represented the first comprehensive study of remote mountain lakes at a European level and assessed the status of remote mountain lakes throughout Europe on the basis of sediment core records and chemical and biological surveys.
MOLAR focuses on detailed studies of a smaller number of key sites located across the climate and deposition gradients of Europe, from the arctic to the Mediterranean and from Scotland to the High Tatra Mountains, to provide high resolution data on their temporal dynamics that can then be used to develop and calibrate predictive models. The project has four overall objectives, each corresponding to a major work package described in the proposal: - to measure and model the dynamic responses of remote mountain lake ecosystemsto acid (sulphur plus nitrogen) deposition;

- to quantify and model pollutant (trace metals, trace organics) fluxes andpathways in remote mountain lakes and their uptake by fish; - to measure and model the temporal responses of remote mountain lake ecosystemto climate variability on seasonal, inter-annual and decadal time-scales. - to continue the development of a high quality environmental database onremote mountain lake ecosystems in Europe and to disseminate results widelyto enhance public awareness, environmental education and environmentaldecision making. The main deliverable generated by this project will be the development of predictive models for acidity, pollutant flux and climate variability that can be used in scenario assessment studies, especially those scenarios associated with present and forthcoming UNECE protocols and General Circulation Model (GCM) predictions for Europe. In the future these models may be linked to evaluate the interaction between acidity, trace pollutants and climate. In addition to model development, much of the field and laboratory work proposed is innovative for studies of such remote sites, especially: the focus on the seasonal dynamics of the lake systems; the emphasis on nitrogen deposition and its biological impact; the study of microbial food webs in relation to acidity; the on-site collection and measurement of atmospheric pollutants; the use of radio-tracers to validate pollutant transport models; the study of trace metal (especially mercury) and trace organic uptake by fish; the on-site monitoring of climatic conditions and their relationship to water column behaviour; the development of a methodology to infer climate trends from the high resolution analysis of recent sediments. MOLAR conforms closely to the aims of both Section 1.2.2.1 (functioning of ecosystems) of the Environment and Climate Work Programme and the thematic network TERI. The proposal is submitted by a pan-European consortium and presents the scientific background and rationale to each work package and describes the field, analytical and integrative tasks involved. It also details the work schedule and resources required to undertake the work. Remote mountain lakes; modelling; atmospheric deposition; pollutant flux; climate variability ecosystem response; limnology; ecology; palaeoecology.