The world's biggest risks

World locked into 'alarming' global warming: World Bank

The dried cracked bed of the Qaraoun artificial lake is seen in West Bekaa, Lebanon, Sept. 19, 2014.
Mohamed Azakir | CNBC

The world is locked into 1.5°C global warming, posing severe risks to lives and livelihoods around the world, according to a new climate report commissioned by the World Bank.

The report, which called on a large body of scientific evidence, found that global warming of close to 1.5°C above pre-industrial times – up from 0.8°C today – is already locked into Earth's atmospheric system by past and predicted greenhouse gas emissions.

Such an increase could have potentially catastrophic consequences for mankind, causing the global sea level to rise more than 30 centimeters by 2100, droughts to become more severe and placing almost 90 percent of coral reefs at risk of extinction.

The World Bank called on scientists at the Potsdam Institute for Climate Impact Research and Climate Analytics and asked them to look at the likely impacts of present day (0.8°C), 2°C and 4°C warming on agricultural production, water resources, cities and ecosystems across the world.

Their findings, collated in the Bank's third report on climate change published on Monday, specifically looked at the risks climate change poses to lives and livelihoods across Latin America and the Caribbean, Eastern Europe and Central Asia, and the Middle East and North Africa.

In the report entitled "Turndown the heat – Confronting the new climate normal," scientists warned that even a seemingly slight rise in global warming could have dramatic effects on us all.

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"A world even 1.5°C [warmer] will mean more severe droughts and global sea level rise, increasing the risk of damage from storm surges and crop loss and raising the cost of adaptation for millions of people," the report with multiple authors said. "These changes are already underway, with global temperatures 0.8 degrees Celsius above pre-industrial times, and the impact on food security, water supplies and livelihoods is just beginning."

As temperatures rise, heat extremes on a par with the heat waves in the U.S. in 2012 and Russia in 2010 will also become more common, scientists believed. "Everyone will feel the impact, particularly the poor, as weather extremes become more common and risks to food, water, and energy security increase."

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Without concerted action to reduce emissions, the report warns that the planet is on pace for 2°C warming by mid-century and 4°C or more by the time today's teenagers are in their 80s.

A temperature rise of this magnitude would create "a frightening world of increased risks and global instability," the World Bank Group's President Jim Yong Kim said, calling the scientists' findings "alarming."

"Today's report confirms what scientists have been saying – past emissions have set an unavoidable course of warming over the next two decades, which will affect the world's poorest and most vulnerable people the most," Kim said. "Climate change impacts such as extreme heat events may now be unavoidable," he added.

The effects of climate change are already starting to impact on mankind, the president noted, with record-breaking temperatures occurring more frequently, rainfall increasing in intensity in some places, while drought-prone regions like the Mediterranean are getting dryer. A significant increase in tropical North Atlantic cyclone activity is affecting the Caribbean and Central America.

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The new report comes on the heels of strong new warnings from the Intergovernmental Panel on Climate Change (IPCC) about the pace of climate change and the energy transformations necessary to stay within 2°C warming.

Earlier in November, China and the U.S. signed a landmark agreement to reduce greenhouse gas emissions by 2020 but there are fears those curbs don't go far enough to slow the onslaught of global warming. There are still many prominent and influential climate change skeptics to convince too.

Global governments are gathering in Lima, Peru at the start of December for the next round of climate negotiations. The World Bank said its latest report provides "direction and evidence of the risks and the need for ambitious goals to decarbonize economies now."

- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt.