Rex Tillerson, the longtime head of ExxonMobil, won Senate confirmation on Wednesday to be secretary of state. In this new role, Tillerson will be in charge of U.S. international climate negotiations as well as international aid efforts on climate-related disasters.

Yes, you read that correctly: The former head of one of the largest oil and gas companies in the world will now spearhead America's approach to mitigating the effects of climate change.

The final Senate vote was 56 to 43 in favor, with three Democrats and one independent joining Republicans in voting for him. No Republicans opposed Tillerson's nomination.

Even though he easily won victory, the narrow margin meant he was the most hotly contested secretary of state nominee in recent years. For example, former Secretary of State John Kerry was confirmed on a vote of 94 to 3 in 2013.

During his confirmation hearings, Tillerson played down the danger posed by global climate change, setting him apart from the scientific consensus on the issue as well as the view of the national security establishment.

"The increase in the greenhouse gas concentrations in the atmosphere are having an effect," Tillerson said during the hearing on Jan. 11. "Our ability to predict that effect is very limited."

Tanker load unit near LNG plant, Aniva bay, Sakhalin, Russia. Image: Shutterstock / lastdjedai

In response to written questions from Sen. Ben Cardin (D-Maryland), Tillerson departed even further from the scientific consensus, saying that greenhouse gas emissions from fossil fuel burning are "a factor in rising temperatures."

However, he said: "I do not believe the scientific consensus supports their characterization as the key factor."

In reality, there is virtually no debate in the scientific community about whether greenhouse gas emissions are the main cause of global warming since the preindustrial era. The U.N. Intergovernmental Panel on Climate Change, in its most recent report in 2013, said as much, as have numerous other authoritative reports.

Tillerson has not committed to keeping the U.S. within the landmark Paris Climate Agreement, which 196 countries agreed to in 2015 and entered into force in 2016. U.S. leadership was crucial to securing that agreement, which was the first global agreement to commit each country to reduce greenhouse gas emissions.

Tillerson told senators that he intended to keep a "seat at the table" at international climate talks, which could mean pulling out of Paris but remaining within the U.N. Framework Convention on Climate Change, which was negotiated in 1992. If the U.S. does pull out of the Paris Agreement, it could bring a global diplomatic backlash and in turn allow China to take the lead on addressing global warming.

Animation showing 2016 was the warmest year on record since at least 1880. Image: nasa giss

In Tillerson, President Donald Trump is getting an experienced international dealmaker. However, his nomination faced considerable scrutiny due to his ties to Russian President Vladimir Putin, with whom he struck a major partnership to develop oil and gas in the Russian Arctic. That deal was scuttled due to U.S. sanctions imposed in the wake of the Russia's invasion of Ukraine.

Environmental groups responded to Tillerson's confirmation with a fusillade of criticism, vowing to fight his agenda.

"For years much of America's foreign policy was formulated to benefit the oil industry. Now it's being formulated by the oil industry," said 350.org co-founder Bill McKibben in a statement.

"There's no disguising the influence any more, which should make it easier to understand and to resist."

Exxon is currently under investigation by several state attorneys general and the Securities and Exchange Commission for researching climate science since the 1970s, and then paying millions to convince the public that the science linking fossil fuel burning to global warming was uncertain.

In addition, Tillerson may soon be deposed in a climate change lawsuit brought by 21 young Americans who say that the fossil fuel industry and federal government failed to address global warming despite ample scientific evidence of the threat.