For anyone who's in favor of preventing the planet from heating up, there's bad news and good news in the latest big report from the International Energy Agency.

Still going. (Robert Nickelsberg/Getty Images)

The somber stuff first: Global carbon-dioxide emissions from energy reached a record high in 2012, after rising 1.4 percent over the past year. The U.S. and Europe did reduce their emissions, but those gains were swamped by growth in China and India.

If the current emissions pace continues, the report warns, global average temperatures could rise as high as 5.3°C above pre-industrial levels by the end of the century. That, said IEA chief economist Fatih Birol, “would be a disaster for all countries.”

Okay, so... what's the optimistic part? The IEA still thinks it's technically possible for the world to cut emissions by 8 percent by 2020 and stay on track for its declared goal of keeping global warming below 2°C. Just four policies, the agency says, would do the trick:

1) Targeted energy efficiency measures in buildings, industry and transport accounts for nearly half the emissions reduction in 2020, with the additional investment required being more than offset by reduced spending on fuel bills.

2) Limiting the construction and use of the least-efficient coal-fired power plants delivers more than 20% of the emissions reduction and helps curb local air pollution. The share of power generation from renewables increases (from around 20% today to 27% in 2020), as does that from natural gas.

3) Actions to halve expected methane releases into the atmosphere from the upstream oil and gas industry in 2020 provide 18% of the savings.

4) Implementing a partial phase-out of fossil fuel consumption subsidies accounts for 12% of the reduction in emissions and supports efficiency efforts.

The IEA also estimates that these four measures would have zero net economic cost, although they would reshape the energy industry:

Net revenues for existing renewables-based and nuclear power plants increase by $1.8 trillion (in year-2011 dollars) collectively through to 2035, offsetting a similar decline from coal plants. No oil or gas field currently in production would need to shut down prematurely. Some fields yet to start production are not developed before 2035, meaning that around 5% to 6% of proven oil and gas reserves do not start to recover their exploration costs

The idea is that these four measures — which don't require any newfangled or unproven technologies — would buy the world some time while leaders hashed out an international climate treaty and/or figured out how to make deeper emissions cuts in the future in order to stay under that 2°C mark.

Note that the IEA is sounding more sanguine on this score than many others.  Bloomberg recently reported that many climate policymakers were now talking, nervously, about changing the goal, since 2°C was looking increasingly unfeasible.

Further reading:

-- An explainer on where the goal of avoiding 2°C of global warming came from. 

-- A closer look at proposals to phase out fossil-fuel subsidies and to capture methane leaks from oil and gas operations.