These briefings summarise the impacts of global warming at and above 1.5°C relative to pre-industrial levels. Key information is extracted from the Special Reports of the Intergovernmental Panel on Climate Change (IPCC) of its sixth assessment report cycle (AR6). These Special Reports are:
- The Special Report on the Impacts of Global Warming of 1.5°C (SR1.5) from 2018, and
- The Special Report on Climate Change, Desertification, Land Degradation, Sustainable Land Management, Food Security, and Greenhouse Gas Fluxes in Terrestrial Ecosystems (SRLand) from 2019.
- The Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC) from 2019.
These Special Reports represent an invaluable resource to understand the impacts of exceeding 1.5°C and new science published after their compilation has only contributed to an ever clearer picture of the grave consequences of exceeding that limit. In addition to the overview on climate impacts based on the Special Reports, latest information on global mitigation efforts and requirements to meet the 1.5°C limit are also included.
The 1.5°C limit means we can avoid the worst of the climate crisis
The IPCC Special Reports SR.15 and SRLand are clear: limiting warming to 1.5°C can avoid the worst impacts of climate change. Compared to 2°C of warming, 1.5°C would see much less severe extreme events, for example mid-latitude heat waves would be 1°C colder on average. There would also be fewer disruptions to human and ecological systems – crop yield change would affect 158 million fewer people. Limiting warming to 1.5°C means substantially fewer people would be impacted by water scarcity, lack of food security and extreme poverty.
The 1.5°C warming limit is still within reach
Limiting warming to below 1.5°C is still possible but requires very urgent and rapid action now. Stringent emission reductions need to take place in the very near-term to halve current projections for 2030 CO2 emissions. 1.5C pathways require CO2 emissions to peak now and reach net zero by mid-century, with total greenhouse gases quickly following suit in the second half of this century.
Are we on track for 1.5°C?
The world is not on track for 1.5°C and most countries still lack sufficient climate targets. Recent updates to national climate targets presented at the US Climate Leaders’ Summit are a step forward to limiting warming to 1.5°C. The Climate Action Tracker calculates that the impacts of these updates reduce estimated end of century warming to 2.4°C, meaning we are closer to the 1.5°C temperature goal than ever before. These recent updates to national targets have reduced the emissions gap (the gap between current policy projections’ 2030 emissions and a 1.5°C trajectory) – by 11-14% (2.6-3.9 GtCO2e). However, a large gap of 20-23 GtCO2e remains.
Coastal loss and damage for small islands
This commentary on a paper in Nature Sustainability reviews how the study quantifies the impacts of sea-level rise on small island states and estimates the impacts in terms of cost, land loss and population exposure across all small islands worldwide.
Adjusting 1.5°C climate change mitigation pathways in light of adverse new information
This study uses an integrated assessment model to explore how 1.5°C pathways could adjust in light of new adverse information, such as a reduced 1.5°C carbon budget, or slower-than-expected low-carbon technology deployment.
2030 targets aligned to 1.5°C: evidence from the latest global pathways
Our new method applies sustainability limits and minimises the need for carbon dioxide removal to set key 2030 global targets for renewables, fossil fuels and emissions.
The deployment length of solar radiation modification: an interplay of mitigation, net-negative emissions and climate uncertainty
Here, we investigate the deployment timescales of solar radiation modification and how they are affected by different levels of mitigation, net-negative emissions and climate uncertainty.
Emissions as usual: implications for the Safeguard Mechanism of LNG and coal mine projects
This report examines the implications of committed and proposed developments in the LNG and coal mining sectors for reform of Australia's Safeguard Mechanism.
Uncompensated claims to fair emission space risk putting Paris Agreement goals out of reach
Only halving emissions by 2030 can minimise risks of crossing cryosphere thresholds
1.5°C is still in reach to reduce the worst climate risks – but only with immediate mitigation action and shifting finance
How can the EU transform its economy to meet the 1.5°C goal?
What does the 1.5°C goal require from EU climate policy? This 4i-TRACTION policy brief analyses the latest 1.5°C-aligned scenarios and spells out what they imply for EU climate policy.
Institutional decarbonisation scenarios evaluated against the Paris Agreement 1.5°C goal
This study analyses six institutional decarbonisation scenarios published between 2020 and mid 2021 (including four from the oil majors and two from the International Energy Agency. It finds that most of the scenarios would be classified as inconsistent with the Paris Agreement as they fail to limit warming to ‘well below 2 ̊C, let alone 1.5 ̊C, and would exceed the 1.5 ̊C warming limit by a significant margin.