General
http://www.environmentglobe.com/
Environmental news around the world
http://www.ipcc.ch/
Established by WMO and UNEP - the scientific, technical and socio- economic aspects of climate change
Technology
Mobility
http://www.myclimate.org/index.php?&lang=en
Offset your flying impact
Food
International Federation of Organic Agriculture Movements
http://www.ifoam.org/
www.soilassociation.org
UK's leading environmental charity promoting sustainable and organic farming
http://www.bite-back.org/index.php
Campaigning against GMO food
Lifestyle
http://www.footprintnetwork.org Quite good overview of the concept
http://www.climatecrisis.net/takeaction/
Calculate your personal impact and then learn how to reduce it
http://ec.europa.eu/environment/climat/campaign/
European Comission’s campaign „You control climate change.”
http://www.treehugger.com/
Many tips how to live your life in more „green” way
Politics
