New research by the Potsdam Institute, indicates that current emission trends put us on track to raise average temperature by 4˙C by 2100 - or as soon as 2060.
"The effects of 4˙C warming will not be evenly distributed around the world, nor would the consequences be simply an extension of those felt at 2˙C warming. The largest warming will occur over land and range from 4˙C to 10˙C. Increases of 6˙C or more in average monthly summer temperatures would be expected in large regions of the world, including the Mediterranean, North Africa, the Middle East, and the contiguous United States
Projections for a 4˙C world show a dramatic increase in the intensity and frequency of high-temperature extremes. Recent extreme heat waves such as in Russia in 2010 are likely to become the new normal summer in a 4˙C world. Tropical South America, central Africa, and all tropical islands in the Pacific are likely to regularly experience heat waves of unprecedented magnitude and
duration. In this new high-temperature climate regime, the coolest months are likely to be substantially warmer than the warmest months at the end of the 20th century. In regions such as the Mediterranean, North Africa, the Middle East, and the Tibetan plateau, almost all summer months are likely to be warmer than the most extreme heat waves presently experienced. For example, the warmest July in the Mediterranean region could be 9˙C warmer than today's warmest July.
Extreme heat waves in recent years have had severe impacts, causing heat-related deaths, forest fires, and harvest losses. The impacts of the extreme heat waves projected for a 4˙C world have not been evaluated, but they could be expected to vastly exceed the consequences experienced to date and potentially exceed the adaptive capacities of many societies and natural systems."
Thus, given that uncertainty remains about the full nature and scale of impacts, there is also no certainty that adaptation to a 4˙C world is possible. A 4˙C world is likely to be one in which communities, cities and countries would experience severe disruptions, damage, and dislocation, with many of these risks spread unequally. It is likely that the poor will suffer most and the global community could become more fractured, and unequal than today. The projected 4˙C warming simply must not be allowed to occur—the heat must be turned down. Only early, cooperative, international actions can make that happen."
(Above quote from 'Turn Down the Heat: Why a 4˙C Warmer World Must be Avoided'
Potsdam Institute for Climate Impact Research and Climate Analytics for the International Bank for Development and Reconstruction and the World Bank, November 2012) http://climatechange.worldbank.org/sites/default/files/Turn_Down_the_heat_Why_a_4_degree_centrigrade_warmer_world_must_be_avoided.pdf
“The impact on humans and other species of rising fossil fuel emissions will be severe and global. As temperatures rise, rainfall, water supplies and food production will be affected in every continent, causing millions of people to migrate to areas with better prospects, further stressing food supplies and social order. First world countries will not be immune to these impacts.” http://www.ghf-ge.org/human-impact-report.pdf (Global Humanitarian Forum, 2009).
POTENTIAL CIMATE IMPACTS
(Source: p8 Climate Change and Water Resources, Water Aid, 2007
The 2009 Lancet/UCL Commission Report on managing the health impacts of climate change opens with these words:
“Climate change could be the biggest global health threat of the 21st century. Effects on health of climate change will be felt by most populations in the next decades and put the lives and wellbeing of billions of people at increased risk. During this century, the earth’s average surface temperature rises are likely to exceed the safe threshold of 2°C above pre-industrial average temperature.
This report outlines the major threats—both direct and indirect—to global health from climate change through changing patterns of disease, water and food insecurity, vulnerable shelter and human settlements, extreme climatic events, and population migration. Although vector-borne diseases will expand their reach and death tolls, the indirect effects of climate change on water, food security, and extreme climatic events are likely to have the biggest effect on global health.
A new advocacy and public health movement is needed urgently to bring together governments, international agencies, non-governmental organisations, communities, and academics from all disciplines to adapt to the effects of climate change on health."
A 2012 report from the Health Protection Agency analysed the impact of climate change on health in the UK. Among its predictions are 10,000 extra death per annum in the UK from heat stress by 2080. This report has implications for other temperate countries. http://www.hpa.org.uk/hecc2012
The Stockholm Environment Institute estimates that moderate climate change would, by 2025, increase the proportion of the world’s population that live in countries with significant water stress from 34% (in 1995) to 63%. ( “Up in Smoke: Threats from and responses to, the impact of global warming on human development”. Working group of climate change and Development Reports, October, 2004)
“Agriculture will be one of the hardest-hit sectors by climate change, reinforcing the unequal distribution of impacts. In addition to pressures caused by population growth and intensified agriculture, warmer temperatures will lead to increased water evaporation, intensifying the need for irrigation precisely as water becomes even less available… Increasing supply for irrigation will simply not be feasible in many regions, particularly where irrigation capacity is not sufficiently developed to accommodate changing precipitation patterns. In sub-Saharan Africa, for example, where up to 90 percent of agriculture is rain fed, the sector accounts for 70 percent of employment and 35 percent of GNP, and changes in rainfall will have a significant social and economic impact."
("Up in Smoke", 2004 quoted in Climate Change and Water Resources, Water Aid, 2007
“Changes to accessibility of water have the potential to increase conflict, as the competing demands of private, agricultural, and industrial uses for water put pressure on resources. This may exacerbate conflict in existing water stressed areas competing locally for access to natural springs and rivers, as well as lead to conflicts on a larger international trans-boundary scale. For example, in northern Kenya, the Samburu are having to cope with changing patterns of rainfall and reductions in rainfall amount, which coupled with other pressures on the natural resources are leading to increasing conflict among tribal groups over access to scarce water.32 Whereas in Central Asia, reduced water availability for agriculture has increased tensions among the former
(Smith, D.M. Just One Planet: Poverty, Justice and Climate Change. UK: Practical Action Publishing, 2006 p.73)