Science Assessment
and Analysis

Climate science is highly complex and the policy implications are not always clear. We make the latest climate science easily accessible for stakeholders in the international climate change arena.

 ©Sarah Depper, CC BY 2.0
©Sarah Depper, CC BY 2.0

We synthesise and advance scientific knowledge in the area of climate change science, policy and impacts to make it easily accessible for stakeholders in the international climate change arena. This includes conducting our own research (for example, to evaluate the uncertainties in climate science associated with potential mitigation pathways, project sea-level rise or evaluate impacts and risks at different levels of warming) as well as bringing together and communicating the findings of the available scientific literature and providing the context needed to understand their implications. Projections of future climate change are subject to uncertainty, as they depend on a range of developments that cannot be foreseen (e.g. emission pathways). Also, there remain important limitations in the understanding and the modeling of some key processes of the climate system. Much of our work therefore focused on understanding these key process and the probabilities associated with climate impact projections.

Latest

In an interview with the Associated Press, Bill Hare says the new climate bill signed into law is the biggest thing to ever happen on climate policy in the United States. In response to the legislation, other nations will be more likely to take action to reduce future warming.  
Bill Hare speaks with the Washington Post about the possible ripple effects of the historic Inflation Reduction Act. Despite this step in the right direction, there are many forces that continue to push the world off track from limiting temperature rise to 1.5 degrees.  

Publications

The 2015 Paris Agreement sets the objectives of global climate ambition. The scientific community has explored the characteristics of greenhouse gas emission reduction pathways in line with the Paris Agreement. However, when categorising pathways, the focus has been put on the temperature outcome and not on emission reduction objectives. Here we propose a pathway classification that aims to comprehensively reflect the climate criteria set out in the Paris Agreement.  
This study extends the framework of an existing spatially resolved, annual-scale Earth system model (ESM) emulator (MESMER) by a monthly downscaling module (MESMER-M), thus providing local monthly temperatures from local yearly temperatures. MESMER-M is able to statistically generate ESM-like, large initial-condition ensembles of spatially explicit monthly temperature fields, providing monthly temperature probability distributions which are of critical value to impact assessments.  
This study ascribes the observations in increased Atlantic tropical cyclone activity to variations in atmospheric circulation as well as sea surface temperature (SST) increase. Using a novel weather-pattern-based statistical model, the authors find that the warming trend in the Atlantic has doubled the probability of extremely active tropical cyclone seasons.  
This report provides an overview of the best available science and other key concepts of relevance to the achievement of the 1.5°C limit – i.e., the long-term temperature goal (LTTG) of the Paris Agreement – and assesses the adequacy of the mitigation measures and targets of the 33 Respondent States in Duarte Agostinho v Portugal and 32 other States against the LTTG.  

Projects

The Paris Agreement commits all countries to take ambitious steps to guarantee a low carbon future. This requires individual national governments to submit more ambitious emission reduction targets. In support of this urgent need to translate global trajectories to be in line with the Paris Agreement, this project, founded by the IKEA Foundation, shows how a group of countries, across all regions and development spectrum can update their NDCs to be in line with the Paris climate goals.  
The "Climate Action Tracker" is an independent science-based assessment, which tracks the emission commitments and actions of countries.  
The EU-funded project “Constraining uncertainty of multi-decadal climate projections” (CONSTRAIN) will address crucial knowledge gaps in climate science to significantly improve our understanding of how natural and human factors affect multi-decadal regional climate change. The project will deliver improved climate projections of policy relevance for the next 20 to 50 years, contributing to European research on fundamental climate system processes and climate variability.  
IMPACT is a cross-cutting, multi-faceted project that aims to strengthen the connections between the scientific assessments of climate impacts, vulnerability and adaptation to help enable access to finance and help Small Island Developing States (SIDS) and Least Developed Countries (LDCs) implement concrete projects.  
Science and policy to assist and support SIDSs and LDCs to negotiate a strong international climate regime, enabling low carbon development and supporting adaptation needs.