Footprint del agua.

 

Enlace:https://www.google.es/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CCUQFjAA&url=http%3A%2F%2Fwww.waterfootprint.org%2F%3Fpage%3Dfiles%2FWaterFootprintAssessmentManual&ei=ojgZVdHnLcu1UYuqgcAP&usg=AFQjCNFpPTBYZgCHzMTOV1-KpKUloBJTFw&sig2=a0Tanyi9J42BIEvWcW6QMg

Water footprint The best databases on water needs and availability with global coverage are probably the ones available through the Food and Agriculture Organisation (FAO). Research on water footprints is carried out for instance at University of Twente, UNESCO-IHE, the World Water Council, IWMI and WWF. (Relevant links on water footprint). Ecological footprint The water footprint concept was introduced in 2002 by Arjen Hoekstra in analogy to the well known concept of ‘ecological footprint'. The ecological footprint concept was developed in the mid 1990s by Mathis Wackernagel and William Rees. They were worried about the amount of land required to supply the world population with food energy etc, particularly if everybody in this world would adopt a western lifestyle. First of all people need land for living and moving (towns, cities, roads, etc.). Second, there is agricultural land (cropland and pasture) needed to produce the food required. Third, forested land is needed to supply things like wood and paper. Finally, Wackernagel and Rees argued, there is forested land needed to transform the carbon dioxide emitted by human activities into organic matter. They assumed that for every 100 GJ per year of energy consumption from fossil fuels, we need one hectare of forest. The land requirement to compensate for burning fossil fuels is a bit disputed, but apart from this, the idea of calculating an ‘ecological footprint' for individuals or whole nations has become very popular. Land areas that are used in support of more than one person (actually most of the land apart from people's own houses and gardens) can be attributed to individuals based on their proportional share in the use of the land. (Relevant links on ecological footprint) Carbon footprint The carbon footprint is a measure of the impact that human ac-tivities have on the environment in terms of the amount of green house gases produced, measured in units of carbon dioxide. It is an indicator for individuals and organizations to conceptualize their personal or organizational contribution to global warming. The carbon footprint can be seen as the total amount of carbon dioxide (CO2) and other greenhouse gases emitted over the full life cycle of a product or service. A carbon footprint is usually expressed as a CO2 equivalent (in kilograms or tonnes), in order to make the global warming effects of different greenhouse gases comparative and addable. (Relevant links on carbon footprint)