IUCN, the International Union for Conservation of Nature

Climate change predictions indicate that we are facing an unavoidable increase in mean global temperature of between 1.1°C and 6.4°C by the end of the 21st century. The present trends in greenhouse gas emissions unfortunately means that the temperature increase is likely to reach the higher estimates. The consequences of this are dramatic.  An increase in mean global temperatures above 2°C is projected to cause major changes in ecosystem functions and services and threaten the livelihoods of the people who depend on them, as well as increasing food insecurity and conflicts.  In addition, approximately 20-30% of species assessed so far are likely to be at increased risk of extinction if increases in global average warming exceed 1.5-2.5°C (relative to 1980-1999). As global average temperature increase exceeds about 3.5°C, model projections suggest significant extinctions (40-70% of species assessed) around the globe. Therefore, significant actions for reducing greenhouse gas emissions have to be taken now.
 
Deforestation accounts for up to one-third of global greenhouse gas emissions. The degradation and deforestation of tropical forests is a highly complex phenomenon caused by many factors. At the local level, it is fuelled by rural poverty. At the national and global levels, it is fuelled by population growth, economic development, agricultural expansion, mining, and logging as well as by indirect factors such as agricultural subsidies, investment in infrastructure, unclear land tenure, weak government surveillance, demand for timber and non-timber forest products and market pressure on land conversion.

The rural poor, disadvantaged communities and women are particularly vulnerable to the adverse effects of climate change, including climate variability and weather extremes, as their livelihoods often rely on climate-sensitive sectors like agriculture and local natural resources. This might hinder the achievement of development and poverty-reduction goals, unless vulnerable countries and communities are assisted in enhancing their adaptive capacity. Therefore, the international community should work on protecting and enhancing the natural services that support local livelihoods and helping vulnerable communities expand the range of options for coping with and adapting to climate variability and change.