PBL research supports Bonn Climate Conference (COP23)

Overview of PBL studies on COP23

The goals that were set in 2015 are currently in the process of being implemented; policy proposals, National Determined Contributions (NDCs) and concrete measures are being discussed and negotiated in Bonn.

Several PBL researchers are at the conference to help the decision-making process. Here is an overview of PBL reports regarding COP23:

• Governments and non-state actors need to take urgent action to meet Paris Agreement goals
• Two-thirds of major emitting countries not on track to reach Paris climate proposals
• PBL Climate Pledge NDC tool
• There are various pathways towards achieving the 1.5 degree Celsius target
• Greenhouse gas emission levels continued to rise in 2016
• Assessment of US city reduction commitments, from a country perspective
• Early action on Paris Agreement allows for more time to change energy systems

Governments and non-state actors need to take urgent action to meet Paris Agreement goals

Governments and non-state actors need to deliver an urgent increase in ambition to ensure the Paris Agreement goals can still be met, according to a new UN assessment. Researchers of PBL Netherlands Environmental Assessment Agency were among the leading authors of this study.

• UNEP Emissions Gap Report 2017

Two-thirds of major emitting countries not on track to reach Paris climate proposals

In the Paris Climate Agreement countries promised to implement policies to reduce their greenhouse gas emissions. A new study by NewClimate Institute, PBL Netherlands Environmental Assessment Agency and the International Institute for Applied Systems Analysis (IIASA) provides an overview of projected greenhouse gas emissions in 25 major emitting countries up to 2030, based on currently implemented climate policies and the implementation of nationally determined contributions (NDCs). The study concludes that 16 out of the 25 countries and regions analysed are not on track to achieve the NDC targets they have set for themselves. This study updates the 2016 report.

• Greenhouse gas mitigation scenarios for major emitting countries: 2017 update

PBL Climate Pledge NDC tool

The PBL Climate Pledge NDC tool addresses the following three key questions:

• What are the countries’ emissions projections for the NDCs/INDCs for 2030?
• Will the projected aggregated impact of the fully implemented NDCs/INDCs on global emissions, for 2030, be sufficient to achieve the target of staying well below 2 °C / 1.5 °C?
• Are countries on track to meet their 2020 pledges and NDCs/INDCs for the period up to 2030?

To address these questions, the tool shows the projected impact of the emission reduction proposals (2020 pledges or NDCs/INDCs) and current policies, per country and globally, on greenhouse gas emission, up to 2030. This tool analyses the mitigation components of the NDCs/INDCs of 114 of the 189 Parties.

• PBL Climate Pledge NDC tool

There are various pathways towards achieving the 1.5 degree Celsius target

There are several important factors that influence the size of the carbon budgets that are consistent with the ambition of the Paris Climate Agreement ‘to limit global temperature increase to well below 2 °C above pre-industrial levels, and to pursue efforts to limit this increase even further to 1.5 °C’. Some of these factors concern scientific uncertainties (e.g. limitations on the understanding of the climate system), while others are policy choices (e.g. the likelihood with which the target should be achieved). However, under all assumptions and policy choices, negative CO₂ emissions seem crucial to achieve the 1.5 °C target.

• Limiting global temperature change to 1.5 °C

Greenhouse gas emission levels continued to rise in 2016

In 2016, total global greenhouse gas (GHG) emissions continued to increase, by about 0.5%, reaching 49.3 gigatonnes in CO2 equivalent. This was mainly due to the rise in non-CO2 emission levels, estimated at around 1%. With a share of about 28%, non-CO2 emissions form a significant share of global GHG emissions.

• Trends in global CO2 and total greenhouse gas emissions: Summary of the 2017 report

Assessment of US city reduction commitments, from a country perspective

In the United States, 14 of the 25 largest cities have committed themselves to achieving greenhouse gas reduction targets. This study shows that, as a group, the 25 largest US cities are more ambitious than the US national reduction target. If the 11 cities without reduction targets implement measures consistent with the NDC target, the additional reductions would add up to 30 MtCO₂e, and only to 5 MtCO₂e, if they do not.

• Assessment of US city reduction commitments, from a country perspective

Early action on Paris Agreement allows for more time to change energy systems

The IMAGE integrated assessment model was used to develop a set of scenarios to evaluate the Nationally Determined Contributions (NDCs) submitted by Parties under the Paris Agreement. The scenarios project emissions and energy system changes under (i) current policies, (ii) implementation of the NDCs, and (iii) various trajectories to a radiative forcing level of 2.8 W/m² in 2100, which gives a probability of about two thirds to limit warming to below 2 °C.

• Early action on Paris Agreement allows for more time to change energy systems