The 2015 Paris Agreement sets out a global action plan to avoid dangerous climate change by limiting global warming to well below 2°C, whilst pursuing efforts to limit warming to 1.5°C.

However, predicting how the climate will change over the next 20-50 years, as well as defining emissions pathways to keep the world on track, requires a better understanding of how several human and natural factors will affect the climate in coming decades. These include how atmospheric aerosols affect the Earth’s radiation budget, and the roles of clouds and oceans in driving climate change.

CONSTRAIN, a consortium of 14 European partners, is investigating these factors, feeding them into climate models to reduce uncertainties in, and create improved climate projections for, the next 20-50 years, on regional as well as global scales.

It is also translating this new scientific understanding into an improved evidence base aimed at providing up-to-date scientific evidence for international climate policy, and supporting decisions on climate mitigation and adaptation.

CONSTRAIN FOCUSES ON THREE CLIMATE SCIENCE KNOWLEDGE GAPS PLUS ONE POLICY-FACING KNOWLEDGE GAP:

Knowledge Gap A:  The magnitude and pattern of effective radiative forcing.

Knowledge Gap B:  The magnitude of cloud feedbacks and the role of cloud-circulation coupling in determining the pattern of climate change and climate sensitivity.

Knowledge Gap C:  The manner in which ocean variability conditions the response of the climate system to effective radiative forcings on different timescales.

Knowledge Gap D:  Translation of insights and uncertainties in variability and forced response on 20-50 year timescales into improved projections and effective adaptation and mitigation policy decisions.

CONSTRAIN is structured around three science knowledge gaps particularly relevant for climate projections on the 20-50 year timeframe and a fourth knowledge gap on the translation of new science in societal decisions