World, don’t lose heart, but you really need to hustle.

That’s the message from the United Nations as international climate delegates prepare to launch into a new round of negotiations next week aimed at cutting global greenhouse gas emissions.

The world agreed in 2009 to limit global warming to 2 degrees Celsius, or 3.7 Fahrenheit, above preindustrial levels. But a report released Tuesday by the U.N. Environment Program reminds us that we’re not on track to meet that goal — not even close.

Even if all the pledges made to date by various governments to reduce their emissions are fulfilled, the report warns that temperature rise would still overshoot the 2-degree goal. That’s not to say it would be impossible to meet the goal, but a serious sense of urgency would be required.

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The report focuses on the “emissions gap” — the difference between anticipated and needed emissions cuts. From a UNEP press release:

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Even if nations meet their current climate pledges, greenhouse gas emissions in 2020 are likely to be 8 to 12 gigatonnes of CO2 equivalent (GtCO2e) above the level that would provide a likely chance of remaining on the least-cost pathway.

If the gap is not closed or significantly narrowed by 2020, the door to many options to limit temperature increase to a lower target of 1.5° C will be closed, further increasing the need to rely on faster energy-efficiency improvements and biomass with carbon capture and storage.

The report authors suggest initiatives that could keep warming within 2 degrees:

  • Massively and urgently boost energy efficiency — that could reduce annual emissions by 2 GtCO2e by the year 2020.
  • Stop subsidizing fossil fuels — that could reduce emissions by 0.4 to 2 GtCO2e.
  • Curb releases of methane and other short-lived climate pollutants — that could reduce emissions by 0.6 to 1.1 GtCO2e.
  • Continue to foster the development and deployment of renewable energy — that could reduce emissions by 1 to 3 GtCO2e.
  • Overhaul the agricultural sector, which is directly responsible for 11 percent of the world’s emissions — that could reduce emissions by 1.1 to 4.3 GtCO2e.

If you add up the best-case scenarios using those five strategies, you get an annual emissions reduction of 12.4 gigatonnes by 2020 — more than enough to get us on track to meet the goal of limiting warming by 2 degrees Celsius.

Actually doing that, of course, is another matter altogether.