Mitigating climate change - SOER 2010 thematic assessment

• Key facts
• Key messages

Summary:

What are global trends in greenhouse gas emissions?

Scientists estimate that, in order to keep the global temperature increase below 2 °C compared to pre-industrial levels, global greenhouse gas (GHG) emissions must peak by 2020 at a level of 44–46 Gt CO2-equivalent and then be reduced by at least 50 % compared to 1990 levels by 2050. In the past 150 years, there have only been a few periods when CO2 emissions fell, notably during the global recession in the early 1930s and as a result of the oil shock of the late 1970s and early 1980s. Otherwise, CO2 emissions have risen relentlessly throughout the period, notably since the 1950s. Despite significant efficiency improvements, fossil fuel combustion continues to increase. Besides emissions from fossil fuel combustion, deforestation and forest degradation have increased over time. According to the UN-REDD Programme, these account for nearly 20 % of global GHG emissions.

GHG emissions are not equally divided across the world. GHG emissions as defined in the Kyoto Protocol (1) have fallen in the EU during the past 30–40 years; whereas emissions in Asia have increased more than three-fold since 1970.
Many of the ozone-depleting substances that are addressed in the UNEP Montreal Protocol (2) are also potent GHGs, but are not addressed under the Kyoto Protocol. The reduction of GHG emissions due to the Montreal Protocol has been significantly larger than the emission reductions that will take place as a result of the Kyoto Protocol by the end of 2012.

What are European greenhouse gas emission trends?

The 27 Member States of the EU currently contribute around 12 % of annual global anthropogenic direct GHG emissions. In 2007, the EU agreed on an independent binding target to reduce its emissions by at least 20 % by 2020 compared to 1990 levels. This commitment would increase to 30 % if major emitting countries outside Europe made similar challenging commitments under a global climate agreement. The EU is making good progress towards its 2020 target. Emissions of its 27 Member States were 11.3 % below 1990 levels in 2008 and, according to preliminary EEA estimates, 17 % below 1990 levels in 2009. Under the Kyoto Protocol, 15 Member States of the EU ('EU-15') are committed as a group to reduce their GHG emissions by 8 % compared to 1990 levels during the commitment period 2008–2012. The EU-15 is well on track to meeting its target, with emissions in 2008 being 6.9 % lower than the base-year. Preliminary estimates of the EEA indicate that EU-15 emissions were further reduced in 2009 to 13 % below base-year levels. Of the EU-12 Member States, 10 have individual targets and are on track to meet these.

A large proportion of the GHG emission reductions achieved in Europe over the last two decades took place during the 1990s as a result of the economic restructuring that occurred mainly in eastern Europe. Further reductions were achieved as a combined result of policies and measures implemented to reduce GHG emissions, such as the EU Emission Trading Scheme (EU ETS), and more recently from the short-term effects of the global economic crisis.
CO2 emissions from the residential and commercial sectors have fallen significantly since 1990. Greenhouse gas emission increases could be observed due to the consumption of halocarbons (HFCs) used in the production of cooling devices such as air conditioning systems and refrigerators. Other key sources at EU level showing GHG emission increases are road transport (freight and passenger cars), international aviation and maritime transport (3).

What are the challenges?

Looking at the longer term and assuming current trends and policies are continued, global annual GHG emissions are expected to increase from some 40 Gt to almost 70 Gt CO2-equivalent per year in 2050. The reduction pledges made by countries under the 2009 Copenhagen Accord fall short of keeping global GHG emissions below the earlier mentioned peak level of 44–46 Gt CO2-equivalent per year by 2020.

The EU's 20 % reduction target will lead to a lower contribution of the EU to global GHG emissions, going beyond the 8 % reduction foreseen for 15 EU Member States under the current provisions of the Kyoto Protocol. In the short term, and as set out above, the EU-15 is on track to meet its target under the Kyoto Protocol. Assuming the full implementation of recent EU legislation ('climate and energy package'), projections show that the EU will indeed reduce emissions by 20 % in 2020. By then the EU would contribute some 9 % to global GHG emissions.

(1)    The Kyoto Protocol is an international agreement setting binding targets for reducing greenhouse gas emissions in certain countries.
(2)    This international agreement aims at phasing out a number of substances depleting the ozone layer.

(3)    The two latter sectors are not covered by the Kyoto Protocol.