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.
A better integration of health and economic impact assessments of climate change
This study lays out how to integrate the economic repercussions of climate change on people's health with direct health impacts. The authors argue this could provide more realistic scenario projections than health studies on their own and be more useful for adaptation policy.
Kipppunkte und kaskadische Kippdynamiken im Klimasystem
Dieser im Auftrag des deutschen Umweltbundesamtes erstellte Bericht befasst sich mit Kippelementen - sensible Komponenten des Erdsystems, die bei Überschreiten kritischer Schwellenwerte (Kipppunkte) irreversiblen Veränderungen ausgesetzt werden können. Er unterstreicht, dass selbstverstärkende Mechanismen zwischen diesen Elementen zu schnellen, irreversiblen Veränderungen führen können.
Hitzestress und Anpassungsmaßnahmen in der Metropolregion Berlin-Brandenburg
Städte sind dabei besonders anfällig für Hitzestress. Deshalb betrachten wir in diesem Bericht die Folgen des Klimawandels auf die Metropolregion Berlin-Brandenburg, mit einem speziellen Fokus auf die Auswirkungen von Hitzestress und die Entwicklung von Anpassungsstrategien.
Limited reversal of regional climate signals in overshoot scenarios
This peer-reviewed paper analyses what happens in an 'overshoot scenario' - where temperature rise peaks just above 1.5°C, but then return below it by the end of the century. It concludes that despite a drop in warming, regional climate changes may only be partially reversed in the decades after peak warming, demonstrating the value of limiting peak temperatures to as low as possible.
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.
Risks of synchronised low yields are underestimated in climate and crop model projections
This study finds that the jet stream – air currents in the upper atmosphere – can synchronise extreme weather caused by climate change, resulting in crop failures in multiple countries at the same time.
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.
Solar radiation modification: a dangerous distraction from required emissions reductions
Investing precious time and resources in this critical decade to explore SRM technologies distracts from the urgent need to step up mitigation efforts to halve emissions by 2030.
Changes in land cover and management affect heat stress and labour capacity
New study says impacts on heat stress should be accounted for in land cover and land management-related policies because land cover and land management changes affect temperature and humidity, which affect heat stress and labour capacity.