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4.3-C Temperature Jump from Climate Change By 2100

The International Energy Agency says extreme weather events will become much more frequent as a result.

The International Energy Agency on Monday warned that temperatures could jump by as much as 4.3 degrees Celsius by the end of the century and urged countries to improve their pledges on reducing emissions.

In a report ahead of a climate change conference in Paris this year, the IEA said more should be done to reach the goal of keeping the increase in average global temperature below 2C (3.6 degrees Fahrenheit).

Current pledges "will have a positive impact on future energy trends but will fall short of the major course correction required to meet the 2C goal," said the report, which was presented in London.

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Instead it estimated that there would be an average temperature increase globally of around 2.6C by 2100 and said the rise could be higher at 4.3C for countries in the Northern Hemisphere.

"The energy sector must play a critical role if efforts to reduce emissions are to succeed. Energy production and use accounts for two-thirds of the world greenhouse gas emissions," the IEA's executive director Maria van der Hoeven said.

The agency's chief economist Fatih Birol said extreme weather events would become "much more frequent" as a result, with Africa particularly badly affected despite only minimally contributing to the problem.

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Van der Hoeven stressed that "time is of the essence," noting that "the cost and difficulty of mitigating greenhouse-gas emissions increase every year."

While there is "growing consensus among countries that it is time to act," strong vigilance is required to ensure that the pledges are adequate and that commitments are kept, she added.

The IEA suggested five key measures to ensure that global energy-related emissions peak already in 2020.

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They call for improved energy efficiency in key industrial sectors, reducing the use of inefficient coal-fired power plants, increased investment in renewable energy technologies, a gradual phasing out of fossil-fuel subsidies and a reduction in methane emissions in oil and gas production.

"This major climate milestone is possible utilizing only proven technologies and policies and without changing the economic and development prospects of any region," the IEA said.

Countries are preparing for a crucial UN meeting in Paris - the 21st Conference of Parties, or COP 21 - of the UN Framework Convention on Climate Change (UNFCCC), which groups 195 nations.

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The European Union earlier this year formally adopted climate change targets for the Paris conference, including a 40 percent cut in greenhouse gas emissions by 2030 compared to 1990 levels.

The United States, which accounts for 12 percent of global emissions, has announced its intention to reduce them by 26-28 percent in 2025 compared with their level in 2005.

China, which is the world's second-largest economy and accounts for 25 percent of global emissions, has set a target date of "about 2030″ for its emissions to peak, but has not pledged any reductions.

The effects of global warming are frequently projected decades into the future, but two recent reports -- one from the

U.S. Global Change Research Program

and the other

from the U.N.

-- put into sharp focus visible consequences of our warming planet. An increase in temperature, extreme weather, loss of ice and rising sea level are just a few of changes we can measure right now. Let's take a look at some of the most concerning trends.

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Glaciers are shrinking worldwide and permafrost is thawing in high-latitude and high-elevation areas, reports this year's Fifth Assessment Report from the Intergovernmental Panel on Climate Change.

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Only a few extinctions are attributed to climate change, reports the IPCC, but climate change that occurred much more slowly, over millions of years, caused major ecosystem shifts and species extinctions. Land and sea animals are changing their geographic ranges and migratory patterns due to climate change.

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Sea level around the world has increased by about 8 inches since 1880, reports the 2014 National Climate Assessment, which projects a 1 to 4 foot rise by the end of the century.

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Excess CO2 is dissolving in the ocean and decreasing the pH of seawater. The ocean is about 30 percent more acidic than it was in pre-industrial times. More acidity in the oceans makes it harder for animals to form calcium carbonate shells and skeletons and erodes coral reefs.

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The probability of a Sandy-like storm deluging New York, New Jersey and other parts of the East Coast has nearly doubled compared to 1950, according to the American Meteorological Society. Even weaker storms will be more damaging now than they were 10 years ago because of rising sea levels. Superstorm Sandy cost the nation $65 billion, according to the 2014 National Climate Assessment, and 2012's Hurricane Isaac cost $2.3 billion.

The global sea level rises along with the temperature for two major reasons. For one, heat causes water to expand, which causes the existing water to take up more space and encroach on the coast. At the same time, ice at the poles and in glaciers melts and increases the amount of water in the oceans.

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Across the United States, heavy downpours are on the rise, especially in the Northeast and Midwest. Increases in extreme precipitation are expected for all U.S. regions, reports the 2014 National Climate Assessment.

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The most recent IPCC report states with "very high confidence" that current climate-related extremes like heat waves, droughts, floods, cyclones and wildfires are showing that countries around the world, at all development levels, are significantly unprepared. The American Meteorological Society estimates that approximately 35 percent of the extreme heat in the eastern United States between March and May 2012 resulted from human activities' effects on climate. The AMS warned that deadly heat waves will become four times more likely in the north-central and northeastern United States as the planet continues to warm.

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