Space & Innovation

It's a Deal! Pact Approved to Stop Global Warming

A deal to attempt to limit the rise in global temperatures to less than 2C has been agreed at the climate change summit in Paris.

Cheering envoys from 195 nations approved in Paris Saturday a historic accord to stop global warming, offering hope that humanity can avert catastrophic climate change and usher in an energy revolution.

French Foreign Minister Laurent Fabius ended nearly a fortnight of gruelling UN negotiations with the bang of a gavel, marking consensus among the ministers, who stood for several minutes to clap and shout their joy, with some shedding tears of relief.

"I see the room, I see the reaction is positive, I hear no objection. The Paris climate accord is adopted," Fabius declared.

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Turning to a little green hammer with which he formally gave life to the arduously crafted pact, he quipped: "It may be a small gavel but it can do big things."

The post-2020 Paris Agreement ends decades-long rows between rich and poor nations over how to carry out what will be a multi-trillion-dollar campaign to cap global warming and cope with the impacts of a shifting climate.

With 2015 forecast to be the hottest year on record, world leaders and scientists had said the accord was vital for capping rising temperatures and averting the most calamitous impacts from climate change.

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Without urgent action, they warned, mankind faced increasingly severe droughts, floods and storms, and rising seas that would engulf islands and coastal areas populated by hundreds of millions of people.

The crux of the fight entails slashing or eliminating the use of coal, oil and gas for energy, which has largely powered prosperity since the Industrial Revolution began in the 1700s.

The burning of those fossil fuels releases invisible greenhouse gases, which cause the planet to warm and disrupt Earth's delicate climate system.

Ending the vicious circle requires a switch to cleaner sources, such as solar and wind, and improving energy efficiency. Some nations are also aggressively pursuing nuclear power, which does not emit greenhouse gases.

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- Ambitious global warming limit -

The Paris accord sets a target of limiting warming of the planet to "well below" 2.0 degrees Celsius (3.6 Fahrenheit) compared with the Industrial Revolution, while aiming for an even more ambitious goal of 1.5C.

To do so, the emissions of greenhouse gases will need to peak "as soon as possible", followed by rapid reductions, the agreement states.

The world has already warmed almost 1C, which has caused major problems for many people around the world particularly in developing countries, such as more severe storms, droughts and rising seas, according to scientists.

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Environment groups said the Paris agreement was a turning point in history and spelt the demise of the fossil fuel industry, pointing particularly to the significance of the 1.5C goal.

"That single number, and the new goal of net zero emissions by the second half of this century, will cause consternation in the boardrooms of coal companies and the palaces of oil-exporting states," Greenpeace International chief Kumi Naidoo said.

- Enduring money battles -

Developing nations had insisted rich countries must shoulder the lion's share of responsibility for tackling climate change as they emitted most of the greenhouse gases since the Industrial Revolution.

The United States and other rich nations countered that emerging giants must also do more, arguing developing countries now account for most of current emissions and thus will be largely responsible for future warming.

Photos: Earth From Space

On the crucial financing issue, developed countries agreed to muster at least $100 billion (92 billion euros) a year from 2020 to help developing nations.

However, following US objections, it was not included in the legally binding section of the deal.

Ahead of the talks, most nations submitted voluntary plans to curb greenhouse gas emissions from 2020, a process widely hailed as an important platform for success.

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But scientists say that, even if the pledges were fully honoured, Earth would be on track for warming far above safe limits.

In an effort to encourage countries to improve their ambitions, the agreement will have five-yearly reviews of their pledges starting from 2023.

Nations most vulnerable to climate change lobbied hard for wording in the Paris pact to limit warming to 1.5C.

War Of The Words: Climate Change Or Global Warming?

Big polluters, such as China, India and oil producing-giant Saudi Arabia, preferred a ceiling of 2C, which would have enabled them to burn fossil fuels for longer.

Immediately after the signing, China's chief negotiator Xie Zhenhua told his fellow envoys the pact was not perfect.

"However, this does not prevent us from marching historical steps forward," he said.

Nicholas Stern, a former chief economist for the World Bank who has become a prominent global advocate of climate action, also hailed the deal.

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"This is a historic moment, not just for us and our world today, but for our children, our grandchildren and future generations," Stern said.

"The Paris Agreement is a turning point in the world's fight against unmanaged climate change, which threatens prosperity and well-being among both rich and poor countries."

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.

BLOG: War Of The Words: Climate Change Or Global Warming?

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.

PHOTOS: Melting Glaciers

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.

NASA: Global Warming Goes On