Fluxpyr >> Background

The increased emissions of gases such as carbon dioxide, methane or nitrous oxide caused by humans from the burning of fossil fuel, stock rising activities and deforestation, all enhance the "greenhouse effect" and contribute to a progressive and significant increase in the average temperature of the Earth. A consensus exists amongst the scientific community regarding the contribution of mankind to the impacts of global warming, whether already visible or expected. As stated by the fourth and latest Assessment Report from the Intergovernmental Panel on Climate Change (IPCC Fourth Assessment Report: Climate Change 2007), "most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations".

The enhanced emissions of greenhouse gases (GHGs) and subsequent increase in the temperature of the Earth induce drastic changes of the climate, measurable in the cryosphere, atmosphere and oceans. Wind, rainfall and drought patterns are affected, snow and ice cover decreases, the frequency and distribution of storms and hurricanes change, which in turns affect ecosystems: habitats and water availability change, some species are expected to migrate or disappear while others are becoming more invasive. The impact on mountain ecosystems is expected to be especially strong: "Mountainous areas will face glacier retreat, reduced snow cover and winter tourism, and extensive species losses. In southern Europe, climate change is projected to worsen conditions (high temperatures and drought) in a region already vulnerable to climate variability, and to reduce water availability, hydropower potential, summer tourism and, in general, crop productivity" (IPCC 2007).

Substantial information on greenhouse gas emissions and on the carbon sequestration potential of forest, cropland or grassland ecosystems across Europe and worldwide is already available, thanks to past or on-going international projects and networks (e.g. FLUXNET, EUROFLUX, MEDEFLU, CarboEurope, CARBOMONT, AsiaFlux, etc.), but processes involved in the carbon, nitrogen and water cycles and the impacts of climate and land use change on climate and ecosystems are far from being fully understood. Further investigation is therefore needed to assess the impacts of climate change on the local flora, fauna, ecosystems and people, and to search for alternatives to mitigate and adapt to global warming (e.g. reducing GHGs emissions, saving energy, adapting agricultural and tourism practices, etc.).

FLUXPYR focuses on climate and land use change in the Pyrenees, whose ecosystems are known to be particularly fragile and impacted by global warming and changing hydrology. It involves multi-disciplinary teams from Spain, France and Andorra, and combines continuous flux and discrete stock assessments based on ecosystem, atmospheric and satellite studies. It involves the use of micro-meteorological stations (Eddy Covariance Technique) located at different altitudes, portable sensors (for photosynthesis and respiration assessment and GHGs concentration measurements), remote sensing (e.g. satellite and aerial images), and modelling, to assess the impacts of climate and land use change in the Pyrenees, and to propose guidelines for sustainable land and resource management.