Observational evidence that cloud feedback amplifies global warming
It is shown that global cloud feedback is dominated by the sensitivity of clouds to surface temperature and tropospheric stability, which will enable tighter constraints on climate change projections, including its manifold socioeconomic and ecological impacts.
Abstract
<jats:title>Significance</jats:title> <jats:p> A key challenge of our time is to accurately estimate future global warming in response to a doubling of atmospheric carbon dioxide—a number known as the <jats:italic>climate sensitivity</jats:italic> . This number is highly uncertain, mainly because it remains unclear how clouds will change with warming. Such changes in clouds could strongly amplify or dampen global warming, providing a climate feedback. Here, we perform a statistical learning analysis that provides a global observational constraint on the future cloud response. This constraint supports that cloud feedback will amplify global warming, making it very unlikely that climate sensitivity is smaller than 2 °C. </jats:p>