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Doom and gloom about the impact of climate change risks preventing effective action being taken to tackle it, one of the lead scientists in a major UN report into the impact of global warming has said. Chris Field, co-chairman of the working group of the Intergovernmental Panel on Climate Change (IPCC), called for more positivity about the "really exciting opportunities" to adapt to the impact of climate change. In a report released on Monday, the IPCC warns of flooding, droughts, heatwaves and food shortages that are likely to result from rising temperatures and extreme weather patterns. The document calls for governments to take action to prepare for and adapt to the increased risks that climate change brings. Mr Field acknowledged that the impacts of climate change set out in the report were overwhelmingly negative. Read more:Academics warn human survival on the lineNZ unprepared for rising sea levels - reportExtreme weather events due to climate changeWHO: Pollution kills 7 million people every yearClimate change to alter life as we know it "It's true we couldn't find very many benefits of climate change," he said. "I believe that's because there aren't that many." However, he urged policymakers to approach the issue with more positive thinking. "Climate change is as rich with opportunity as it is with danger," he said. "One of the things that made it so difficult for individuals and countries to be serious about climate is that the agenda is such a downer," he said. "If climate change is a total downer because everything looks so serious, and the only ways to cope effectively are to give up all good things in life, it's going to be really hard to take action. "If dealing effectively is taking an innovative, creative, entrepreneurial approach, building great businesses and communities, then it's a problem that we can deal with." Watch: PM John Key on climate change He said that many of the real opportunities for innovation this century were going to be in the energy industries, building sustainable housing and creating new transportation systems. Too much negativity about climate change would mean "we are not going to be able to attract the creative people who build the solutions," he warned. He made his comments after Richard Tol, one of the authors of the report, claimed that a summary document for policymakers was too "alarmist". Benny Peiser, the director of the Global Warming Policy Foundation, a think tank that questions current efforts to tackle climate change, welcomed the report's focus on adaptation. "The signal they are sending out is adaptation: prepare for climate change," he said, arguing that this was a more "cost-effective approach" than trying to stop emissions rising when there was "no chance of international agreement" on such green policies. The IPCC report finds that the world is "in many cases ill-prepared for risks from a changing climate". It says that while there are "opportunities to respond to such risks", it stresses that the risks will be "difficult to manage with high levels of warming", such as 4C (7.2F) above pre-industrial levels. The UN has previously set a target of limiting global warming to 2C (3.6F) by cutting emissions to minimise the impacts.

The risks the report warns of include:

Food Wheat, rice and maize crops in tropical regions will be harmed by increases of 2C or more unless action is taken to adapt. However, some locations may benefit from improved growing conditions. "All aspects of food security are potentially affected by climate change, including food access, utilisation, and price stability," the IPCC says. If average temperature increases were to increase further, to 4C (7.2F) or more than, combined with increasing food demand from a growing population, it would "pose large risks to food security globally and regionally". Species extinction The IPCC warns: "A large fraction of both terrestrial and freshwater species faces increased extinction risk under projected climate change during and beyond the 21st century, especially as climate change interacts with other stressors, such as habitat modification, over-exploitation, pollution, and invasive species." Many species will be unable to relocate quickly enough to keep up with the changes to their habitats as a result of climate change. Trees will die, leading to fewer forests, due to increased temperatures and drought. Marine life is also at risk, with polar ecosystems and coral reefs deemed to be especially vulnerable from ocean acidification, it says. Floods The IPCC says it has "very high confidence" that "coastal systems and low-lying areas will increasingly experience adverse impacts such as submergence, coastal flooding, and coastal erosion" as sea levels rise. Photo / AP Simultaneously more and more people and infrastructure will become exposed to the risks of coastal erosion due to population growth and urbanisation. "The relative costs of coastal adaptation vary strongly among and within regions and countries for the 21st century. Some low-lying developing countries and small island states are expected to face very high impacts," it says. War and peace Photo / AP Climate change will increase the displacement of people who move to escape inhospitable climates. It can also "indirectly increase risks of violent conflicts" such as civil war by increasing poverty and economic shocks. Water supplies The more the climate warms, the more people will experience "water scarcity", the IPCC finds. If carbon emissions remain high, droughts will become more frequent in dry regions by the end of the century - although "water resources are projected to increase at high latitudes". Health "Throughout the 21st century, climate change is expected to lead to increases in ill health in many regions and especially in developing countries with low income," the IPCC says. Heatwaves and fires will increase risks of direct loss of life, while declines in crops in some regions will contribute to under-nutrition. There could also be some positive effects including "modest reductions in cold-related mortality and morbidity in some areas due to fewer cold extremes'' but globally the negatives will increasingly outweigh the positives. It finds that by the year 2100, in a high-emissions scenario, high temperature and humidity in some areas for parts of the year is likely to "compromise normal human activities, including growing food or working outdoors". - The Daily Telegraph