The US and China began 2012 with much in common. Both were facing national leadership changes, both had massive economies at critical junctures and both were essential to a productive global discussion on climate.

Yet the US-China relationship was marked from the start by tension, with both countries investigating the other’s trade subsidies and casting doubt on the likelihood of productive dialogue anytime soon.

“In theory, there is much to gain: the combination of US technologies and Chinese low cost manufacturing and large markets could bring benefits to the world’s two largest emitters of greenhouse gases,” our boss wrote. “Getting to real cooperation, however, has proved difficult.”

It was not a promising start.

Climate change: do we care?

In March, the Intergovernmental Panel on Climate Change reported that climate extremes coupled with social vulnerabilities could lead to more natural disasters. Grave though the warning was, the public hardly seemed to notice. In a country consumed with the political sideshows of the campaign and a staggering economy, the environment barely registered in the national conversation.

Among those Americans who could be bothered to care about climate change, there was no agreement on what to talk about. Climate change remained a polarising subject in the US in 2012.

Jan McGirk covered the contentious battles over how global warming should be taught to US schoolchildren (arguments that were even more fierce in oil-rich states). The conservative Heartland Institute posted billboards along the highways comparing people who believe the climate is changing to the Unabomber.

And Michael Mann, the US scientist who created the famous “hockey stick” graph showing the spike in global temperatures, said that he is still viciously harassed by people resistant to his theories.  

The nation’s scientists remained undaunted. As the G8 summit and Rio+20 meeting approached, the national science academies of the US, China and 13 other countries issued a joint statement asking world leaders to – gasp – actually consider science and technology when addressing the world’s problems.

“Our academies of science are committed to . . . better understanding the causes of disasters, finding ways to make society more resilient, making that information widely available, and helping to implement the many actions needed,” they wrote.

It was a generous offer, but one the world’s leaders largely ignored. Though the G8 summit yielded some promising commitments to limit short-lived climate pollutants, Rio+20 was largely panned as a failure.

After a long primary that at times became cartoonish, particularly when science and climate came up (“I refer to global warming not as climate science, but political science!” one-time frontrunner Rick Santorum crowed at one point), former Massachusetts governor Mitt Romney finally secured the Republican nomination on 29 May.

Romney and Obama squared off against one another in the longest, hottest summer in American memory. By August, the US was in its worst drought in 56 years. More than half of states were officially declared disaster areas. Drought ruined crops and forced a nuclear reactor to shut down.

One might think that people watching their nation wither before their eyes might start demanding tough answers from their politicians. Instead, the environment hardly factored into the presidential contest.  

The candidates clashed over new fuel standards Obama unveiled in August, one of the few unambiguously pro-environment moves of his first term. Climate change was a punch line at the Republican National Convention, and was barely mentioned at the Democratic gathering.

Romney and Obama traded more barbs over China, with each eager to appear tough on the superpower rival. Obama’s decision to block a Chinese-owned company from owning four wind farms in the US was seen as a vote-getting ploy that could potentially harm US interests in the long run.

As the candidates worked to position the US and China as rivals, the real world continued to prove how intertwined the two countries are. Ross Perlin reported on the Chinese-built infrastructure proliferating across the US. Charles West highlighted the US’s controversial coal exports, a strategy that keeps the nation’s emissions numbers down but does nothing to reduce them globally. The US and China continued to fight bitterly over trade in solar panels, to the dismay of those hoping for climate negotiations between the world’s two biggest carbon emitters.

Climate change was not mentioned at the presidential debates for the first time since 1984. It seemed that the environment had fallen permanently off the nation’s radar.  

And then Superstorm Sandy hit.

Natural disasters: Hurricane Sandy

The mega-storm smashed into the east coast of the US in the final days of October, killing 131 people and causing more than US$63 billion in damages. In response, the Republican mayor of New York City publicly endorsed Barack Obama, saying that he believed climate change was behind the storm that wreaked unprecedented havoc on his city.

Psychologists say that people are more likely to act once they feel they have directly experienced the effects of climate change. Sandy upended millions of lives. It’s impossible to say if it made the difference, but on 6 November Barack Obama was re-elected president.

As the year draws to a close and Obama’s second inauguration approaches in January, it’s hard to say what’s in store for the US. Obama faces some key environmental decisions in his second term, like the Keystone XL pipeline, new emission standards for power plants and a changing global energy landscape. But does he have the political stomach to fight for the climate?

“I am a firm believer that climate change is real, that it is impacted by human behaviour and carbon emissions,” Obama told reporters at his first post-election press conference, “(but) if the message is somehow we’re going to ignore jobs and growth simply to address climate change, I don’t think anybody’s going to go for that.”

What is clear is that, like it or not, China and the US need each other. At a live chat in November hosted by chinadialogue and Tea Leaf Nation, participants from both countries acknowledged that the countries have far too much at stake to alienate the other.

"The US and China are the number one and number two economies in the world,” said Yang Fuqiang of the Natural Resources Defense Council. “They both have to enhance open discussion, information and consultation rather than playing tough with each other. These two economies need to figure out how to complement each other.”