Top 10 insights in climate science in 2020

"This series is a critical part of our mission to get the latest science to decision makers in an accessible format to help accelerate transitions to sustainability," says Wendy Broadgate, Future Earth Global Hub Director, Sweden. "Worsening wildfires, intensifying storms, and even the ongoing pandemic are all signals that our relationship with nature is deteriorating, with deadly consequences."

"All parts of our world are affected by the climate crisis, and each continent, country, city and village depends on how well we manage Earth's natural carbon sinks – that's what the overwhelming scientific evidence shows," says Johan Rockström, who is also co-chair of the Earth League and co-chair of Future Earth's Advisory Committee. "Because we all share the same small planet, and there are planetary boundaries, we cannot rely on nature to support us if we do not support nature. Just look at the stressed tropical forests that so conveniently have been taking up huge amounts of CO2, but this might now come to a peak and decline. From all these scientific insights, one political insight should arise: if we want to have a chance of stabilizing our climate, for the sake of our own safety, the last chance to reduce greenhouse gases is now."

This year's 10 new insights:

1. Improved understanding of Earth's sensitivity to carbon dioxide strengthen support for ambitious emission cuts to meet Paris Agreement
The climate's sensitivity to carbon dioxide – how much the temperature rises with a certain increase of emissions – is now better understood. This new knowledge indicates that moderate emission reductions are less likely to meet the Paris climate targets than previously anticipated.

2. Emissions from thawing permafrost likely to be worse than expected
Emissions of greenhouse gases from permafrost will be larger than earlier projections because of abrupt thaw processes, which are not yet included in global climate models.

3. Tropical forests may have reached peak uptake of carbon
Land ecosystems currently draw down 30% of human CO2 emissions due to a CO2 fertilization effect on plants. Deforestation of the world's tropical forests are causing these to level off as a
carbon sink.

4. Climate change will severely exacerbate the water crisis
New empirical studies show that climate change is already causing extreme precipitation events (floods and droughts), and these extreme settings in turn lead to water crises. The impact of these water crises is highly unequal, which is caused by and exacerbates gender, income, and sociopolitical inequality.

5. Climate change can profoundly affect our mental health
Cascading and compounding risks are contributing to anxiety and distress. The promotion and conservation of blue and green space within urban planning policies as well as the protection of ecosystems and biodiversity in natural environments have health co-benefits and provide resilience.

6. Governments are not seizing the opportunity for a green recovery from COVID-19
Governments all over the world are mobilizing more than US$12 trillion for COVID-19 pandemic recovery. As a comparison, annual investments needed for a Paris-compatible emissions pathway are estimated to be US$1.4 trillion.

7. COVID-19 and climate change demonstrates the need for a new social contract
The pandemic has spotlighted inadequacies of both governments and international institutions to cope with transboundary risks.

8. Economic stimulus focused primarily on growth would jeopardize the Paris Agreement
A COVID-19 recovery strategy based on growth first and sustainability second is likely to fail the Paris Agreement.

9. Electrification in cities pivotal for just sustainability transitions
Urban electrification can be understood as a sustainable way to reduce poverty by providing over a billion people with modern types of energy, but also as a way to substitute clean energy for existing services that drive climate change and harmful local pollution.

10. Going to court to defend human rights can be an essential climate action
Through climate litigation, legal understandings of who or what is a rights- holder are expanding to include future, unborn generations, and elements of nature, as well as who can represent them in court.