United Nations and Kyoto Protocol:

Intergovernmental Panel on Climate Change, IPCC
Assess of the scientific, technical and socio-economic information relevant for the understanding of the risk of climate change

IPCC, Climate Change 2007: the physical science basis. Summary for policy makers

United Nations Framework Convention on Climate Change, UNFCCC
Official UN site pertaining to climate change and international agreements and conferences

Full Text of the Kyoto Protocol Treaty

Current list of countries that have ratified the Kyoto Protocol

Organisations on Climate Change:

The Climate Institute

Pew Center on Global Climate Change

World Resources Institute

David Suzuki on Climate Change

Climate Action Network (CAN)
A worldwide network of over 340 NGOs working to promote government and individual action to limit human-induced climate change

The Union of Concerned Scientists

Center for International Climate and Environmental Research - Oslo, CICERO

The Climate Group

International Emissions Trading Association

Philosophical Transactions of the Royal Society, vol. 365, 1925-1954 (2007), "Climate
change and trace gases" by Dr James Hansen et al

Renewable Energy and Energy Efficiency Organisations:

The Renewable Energy and Energy Efficiency Partnership (REEEP)

EREN, Department of Energy, USA

Eco Web - Green Pages
The global diretory for environmental technology

Information:

ClimateWire
A leading multi-sectoral, international news service specifically focussing on the issue of climate change

Climate Ark

World Environment News updates

Clean Edge
The Clean-Tech Market Authority

Turn Up The Heat!
Greenwash and Carbon Offset Bluffers Exposed

Worldchanging
Another world is here

Eco 4 the world
The enviromental social networking edutainment portal

Energy & Climate Info
by the World Business Council for Sustainable Development

Governmental Institutions:

United Kingdom

UK Carbon Trust

UK Meteorological Office

UK Department of Environment, Food and Rural Affairs

EU:

Official climate change web site of the European Union

EU Community Transaction Log
Registry of Carbon Trading Regulative Bodies in the EU

Australia:

Australian Greenhouse Office

CSIRO

National Emissions Trading Taskforce
Initiative by Australian state governments for a nationwide carbon trading scheme from 2010 on

NSW Greenhouse Gas Reduction Scheme - GGAS
Australia's first mandatory carbon emissions reduction scheme in the state of NSW

USA:

US EPA's Climate Change Site

California Climate Action Registy