President Trump tweeted about the climate and environment on Wednesday, but was he right?

In the first part of the Twitter thread, the president said: “Which country has the largest carbon emission reduction? AMERICA!”

The United States did indeed have the largest drop in total emissions from 2005, its peak year, through 2017. Total emissions of carbon dioxide fell 862.5 million tons, according to the Global Carbon Project. That period included the Great Recession, which helped drive down emissions.

Analysts say the U.S. drop in emissions was due largely to conversions from coal plants to natural gas-fired electric plants. But the pace of those conversions is slowing.

In 2018, U.S. emissions bounced back up 3.4 percent, according to a study by the independent Rhodium Group.

In addition, as a percentage of total emissions, arguably a more relevant metric, the U.S. performance has been outdone by many countries, according to data on national emissions from the Global Carbon Project. From 2005 through 2017, U.S. emissions fell 14 percent. But over the same period, Britain’s plunged 33 percent. Italy’s tumbled 28 percent. France’s fell 18 percent.

Trump was even more flatly wrong in some other things he said.

Second, he tweeted: “Who has dumped the most carbon into the air? CHINA!”

China has overtaken the United States as the biggest annual emitter, but China still has a long way to go before it catches up with all the emissions the United States has dumped into the atmosphere during the industrial era. From 1959, China emitted 196.6 billion tons of carbon dioxide, according to the Global Carbon Project. The United States, by comparison, has emitted 286.2 billion tons.

Third, he tweeted: “Who’s got the world’s cleanest and safest air and water? AMERICA!” And later, he said: “I want crystal clean water and the cleanest and the purest air on the planet — we’ve now got that!”

The Post Fact Checker has taken this on before:

Trump withdrew the United States from participation in the Paris accord to combat climate change, and he falsely asserted that the United States had the world’s “cleanest air” and “cleanest climate” and even the “cleanest water.”
The United States actually ranks 27th in the world, according to the authoritative Environmental Performance Index, a project of Yale and Columbia universities. It ranks 10th for air quality — but 88th on exposure to particulate matter, an indication of the health effects from pollution — and 29th for water and sanitation. The United States is tied for first place — with nine other countries — for the quality of drinking water.
As for whether things have improved under Trump, that’s hard to track in the available data — in fact, the number of unhealthy days in the United States went up from 2016 to 2017, according to government data — but he has taken a number of actions that could reverse or slow the gains made in air and water quality since 1990.

Fourth, Trump tweeted: “The Democrats’ destructive ‘environmental’ proposals will raise your energy bill and prices at the pump. Don’t the Democrats care about fighting American poverty?”

This is complicated. Democrats have different proposals. And different policies have different impacts. The plan unveiled by Sen. Bernie Sanders (I-Vt.) includes no carbon taxes, precisely to sidestep the type of assertion Trump made today. No one is pushing for higher gasoline prices — even though they would make for effective climate policy and bring down oil use.

Ironically, the Energy Department on Wednesday issued two rules — one final and one proposed — that will prolong the sales of a range of incandescent lightbulbs that were supposed to be phased out on Jan. 1, 2020. Consumers were expected to buy more energy-efficient LED and compact fluorescent bulbs. Those might be more expensive at the outset, but the more efficient bulbs save much more than that in electricity costs.

Next, Trump tweeted: “The badly flawed Paris Climate Agreement protects the polluters, hurts Americans, and cost a fortune. NOT ON MY WATCH!”

It’s not too clear what polluters he has in mind. The president has attempted to protect Appalachian coal mining companies by rolling back a variety of regulations for protecting streams and wetlands. He has also responded to small to medium independent oil and gas companies by seeking to lift limits on emissions of methane, a potent greenhouse gas. Many of the companies and the American Petroleum Institute want voluntary measures so firms do not have to spend money to control leaks at the wellhead or along pipelines.