The United Nations Environment Programme (UNEP) has released its Emissions Gap Report 2013, which highlights that additional measures to stem up the growth in CO2 emissions will be necessary to reach the 2°C target. Even if nations meet their current climate pledges, greenhouse gas (GHG) emissions in 2020 are likely to be 8 to 12 Gt 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. This will mean much higher rates of global emission reductions in the medium term; greater lock-in of carbon-intensive infrastructure; greater dependence on often unproven technologies in the medium term; greater costs of mitigation in the medium and long term; and greater risks of failing to meet the 2°C target. In order to be on track to stay within the 2°C target and head off the negative impacts outlined above, the report says that emissions should be a maximum of 44 GtCO2e by 2020 to set the stage for further cuts needed-to 40 GtCO2e by 2025, 35 GtCO2e by 2030 and 22 GtCO2e by 2050. As this target was based on scenarios of action beginning in 2010, the report finds that it is becoming increasingly difficult to meet this goal.