Five years ago this month, negotiators from nearly 200 countries agreed at a conference near Paris to hold “the increase in the global average temperature to well below 2 degrees Celsius above pre-industrial levels.” But President Trump withdrew the United States from the accord, despite widespread opposition from other heads of state and a sizable majority of the American people, making it the only nation to do so. President-elect Joe Biden ran on rejoining the agreement, and he says the United States will do so on his first day in office. This tortured political controversy over the Paris agreement is unique to the United States, and it can be traced in part to persistent myths surrounding it.

Myth No. 1

The Paris agreement compels the U.S. to meet emissions targets.

“Believe me, we have massive legal liability if we stay in,” Trump said in 2017 when justifying his decision to withdraw from the agreement. Other conservatives have echoed that argument, and even some publications picked up the message, with Quartz claiming, “The Paris Agreement compels countries to reduce greenhouse gas emissions by self-determined targets.”

Only the last part of that assertion is true. The agreement is a voluntary and non-legally-binding, allowing all nations to set their own emissions goals through “nationally determined contributions.” There are no legal penalties if a nation does not meet its target — and hence no sense in which the agreement “compels” countries.

In fact, the voluntary structure of the deal was a deliberate effort to address criticisms from U.S. conservatives of the 1997 Kyoto Protocol, a formal treaty that required legally binding emissions cuts by developed nations like the United States but not developing countries. By contrast, with the Paris agreement, the Obama administration and its allies recognized that a voluntary pact would enable all nations, including the United States and developing countries to set emissions targets and make other climate pledges. Under U.S. law, the Paris accord is an executive agreement, not a treaty and does not require Senate ratification.

Myth No. 2

China is taking stronger climate action than the U.S.

Compared with the United States, “China and others are doing much more, much faster to bend the curve” on climate change, says technologist Michael Barnard. When Trump was planning to withdraw from the Paris agreement, Sarah Zheng and Julia Hollingsworth wrote in the South China Morning Post that the development meant China was “poised to be the global leader.”

 Yet U.S. annual emissions of carbon dioxide today are 15 percent of the global total, a distant second to China, the largest annual emitter at 28 percent of overall emissions, which is more than the United States, Britain and the European Union combined. From 2005 to 2014, China’s carbon emissions grew by more than 53 percent, while from 2005 to 2016, U.S. carbon emissions fell by 14 percent.

 That China remains in the Paris agreement doesn’t change much. Under the deal, the United States set a goal of cutting its emissions at least 26 percent below 2005 levels by 2025, an ambitious target it’s not on track to meet. China’s Paris pledge, on the other hand, allows it to keep increasing emissions during this decade — holding off until 2030 to cap its emissions peak, a target that many observers, including some in China, believe would accomplish little.

China recently announced a net-zero emissions goal for 2060, but it is also building new coal power plants. Biden has said he will commit the United States to net zero electricity emissions by 2035 and zero overall emissions by 2050. In the end, both nations will have to cut their emissions more deeply and more quickly to meet the Paris temperature goal.

Myth No. 3

Existing clean-energy technology can meet the Paris goals.

One recent report argues that Europe can achieve climate-neutral goals that would limit temperature increases to the Paris agreement’s preferred number of less than 1.5 degrees Celsius by fully embracing renewable-energy technologies. Other advocates, such as political scientist Joshua S. Goldstein and energy engineer Staffan A. Qvist, have suggested that expanded nuclear power can meet global clean-energy needs.

 Most analysts believe that both of these contentions are deeply flawed, as they make assumptions about cost, capacity and other issues that have repeatedly been proved untrue in the real world. Wind and solar costs have fallen dramatically over the past 15 years, but deploying them at scale would demand new technologies such as more efficient, affordable electricity storage when the sun doesn’t shine and the wind doesn’t blow. Expanding nuclear power faces high hurdles involving cost, safety and social acceptance, and it would require technology advances to become commercially viable in much of the world. Electric vehicles hold real promise in the effort to decarbonize transportation, but questions remain about the availability of key raw materials for batteries. New clean-energy technologies are still needed to meet growing global energy demand while bringing emissions to net zero by 2050.

Myth No. 4

Carbon dioxide is by far the most important greenhouse gas to cut.

In 2012, Duncan Clark wrote a Guardian column titled “Cutting CO2 is more important than stopping methane.” And a Union of Concerned Scientists “explainer” states that “climate change is primarily a problem of too much carbon dioxide.”

 It is true that CO2 causes about two-thirds of warming. But the top United Nations climate science report on meeting the Paris temperature goal found that reducing non-CO2 climate pollutants, including methane, black soot and hydrofluorocarbons (HFCs), will also be necessary.

 Cutting non-CO2 pollutants will be especially important in limiting temperature increases in the next decade or two, since higher temperatures over this period could prompt self-reinforcing warming in natural systems, destabilizing the global climate. For example, HFCs, methane and black soot are causing most of the melting of Arctic sea ice, and losing that ice permanently would lead to far more warming, making extreme climate change much harder to prevent.

These pollutants are also much shorter-lived in the atmosphere, meaning reducing them now would curb warming more quickly than cutting CO2, much of which stays in the atmosphere hundreds of years. Limiting super pollutants could prevent up to 1 degree Fahrenheit of warming by 2050.

Myth No. 5

The Paris agreement can't affect climate change.

Trump White House spokesman Judd Deere has said the agreement “has done nothing to reduce greenhouse gas emissions.” Sen. James M. Inhofe (R-Okla.) claims that “the Paris Climate Agreement is nothing but empty promises.” And Sen. Marco Rubio (R-Fla.) has said it won’t stop sea level rise or lower the Earth’s temperature.

 But the cumulative emissions reductions from just the initial Paris pledges “would result in around 1.1C less warming in 2100,” according to an average of nine leading studies on the topic. The Paris accord recognizes that these existing pledges are just the beginning, and all nations have agreed to set more ambitious targets every five or ten years going forward. Under Biden, for example, the United States will probably set a new, more aggressive climate target for 2030 at a U.N. conference next November in Britain. The Paris agreement has also generated climate action promises from every nation, and it led many countries to begin serious domestic emissions programs for the first time. At least 192 countries representing 96 percent of emissions have submitted “nationally determined contributions” to reduce emissions under the agreement.

Twitter: @paulbledsoe

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