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Climate Change

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Scientists have mostly stopped arguing about whether humans are warming the planet. Last year was again the hottest on record, and the globe is on track to heat up by more than 2 degrees Celsius (3.6 degrees Fahrenheit), a gain that scientists say is an irreversible tipping point that will unleash catastrophic floods, droughts and storms. There’s also a consensus that people are ill-prepared for the impact. That spurred the world’s nations to take their boldest step yet to stem climate change, agreeing to a historic pact in Paris in 2015 to limit fossil-fuel pollution. Now U.S. President Donald Trump says that the U.S. will withdraw from the agreement, undercutting efforts to fight global warming.  

The Situation

Trump said the pact favored other countries at the expense of U.S. workers and amounted to a "massive redistribution" of U.S. wealth. He walked away despite the objections of many corporations and global leaders who vowed to press ahead without the U.S., the second-largest emitter of carbon dioxide. The accord brought together almost 200 countries into a United Nations-sponsored deal to cut the greenhouse gases that trap heat in the Earth’s atmosphere. It was hailed as the first universal deal because the previous one, the 1997 Kyoto Protocol, was never ratified by the U.S. and didn't set binding targets for China and India, now among the biggest polluters. This time, nations made voluntary commitments, with China agreeing that its emissions will peak in about 2030. The targets aren't legally binding in the same way as Kyoto, though countries must report their progress. Even before Trump's announcement of the U.S. withdrawal, he'd moved to dismantle environmental programs: He's called for a review of fuel-economy standards for cars and a reversal of regulations on power plants. Even if the U.S. had stayed in and all the accord's pledges were met, the globe was expected to warm by as much as 3.4 degrees Celsius this century. That's alarmed the most vulnerable nations -- including island states imperiled by rising seas -- and led countries to agree to meet every five years to seek ways to cut further. 


The Background

The UN climate agreement overcame years of fractious negotiations over who should do what to combat global warming. Trump's move marks a dramatic rupture from the policies of the past four U.S. presidents, and puts the country in a league with just two other nations -- Syria and Nicaragua -- that aren't participating. It threatens the political foundations of the global fight against climate change and interrupts a planned $100-billion-a-year stream of funds that industrial nations had pledged to persuade developing ones to participate. Poorer nations have long insisted that their priority is to take people out of poverty as quickly as possible, and tapping fossil energy is often the cheapest way to do so. Over the last decade, governments began imposing costs on polluters that reflect the broader harm to society, either by levying taxes or by adopting various cap-and-trade systems for emissions permits.  

The Argument

Optimists say Trump's withdrawal won't stop the shift to a lower-carbon future already underway, and that U.S. states such as California will still move forward with aggressive policies. Companies and homeowners are installing solar panels, switching to energy-efficient lighting and taking other steps as technologies improve and the plunging cost of renewable energy makes it competitive with fossil fuels. Rising consumer awareness and political pressure have been propelled by an expanding body of research that predicts global warming will take a growing toll on the globe's economiesfood production, fresh water supplies and human health. Yet the arguments that crippled the Kyoto Protocol have hardly changed. There’s a small group of global-warming skeptics who convinced Trump to change course. Some scientists and business leaders who acknowledge the risk recoil at the cost of halting climate change or disagree on the best way to act. The Paris agreement would require $13.5 trillion of spending through 2030, according to the International Energy Agency, with another $3 trillion needed to get the planet onto a 2-degree pathway. There are concerns that the U.S. withdrawal could have a domino effect on the participation of other countries, making it almost impossible, and even more expensive, to stop climate change. 

The Reference Shelf

  • A QuickTake Q&A on what's comes of the Paris climate accord without the U.S. 
  • Bloomberg News examined the potential environmental impact of a U.S. pullout from the Paris accord. 
  • An opinion piece on why cities will lead the fight on climate change by Michael R. Bloomberg, the founder and majority owner of Bloomberg News parent Bloomberg LP. 
  • The text of the Paris agreement.
  • Graphics and data on climate change from Bloomberg New Energy Finance.
  • The pope’s encyclical on climate change.
  • The International Energy Agency’s website on climate change.
  • United Nations Intergovernmental Panel on Climate Change reports.
  • Bloomberg Markets article on the efforts of Tom Steyer, a billionaire hedge fund manager, to highlight the risks of climate change.
Source: UN IPCC; white blocks indicate insufficient data

    First published Nov. 11, 2013

    To contact the writers of this QuickTake:
    Jess Shankleman in London at
    Alex Morales in London at

    To contact the editor responsible for this QuickTake:
    Leah Harrison at

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