To what extent can cirrus cloud seeding counteract global warming

The idea of modifying cirrus clouds to directly counteract greenhouse gas warming has gained momentum in recent years, despite disputes over its physical feasibility. Previous studies that analyzed modifications of cirrus clouds by seeding of ice nucleating particles showed large uncertainties in both cloud and surface climate responses, ranging from no effect or even a small warming to a globally averaged cooling of about 2.5 °C. We use two general circulation models that showed very different responses in previous studies, ECHAM6-HAM and CESM-CAM5, to determine which radiative and climatic responses to cirrus cloud seeding in a 1.5 × CO 2 world are common and which are not. Seeding reduces the net cirrus radiative effect for −1.8 W m −2 in CESM compared with only −0.8 W m −2 in ECHAM. Accordingly, the surface temperature decrease is larger in CESM, counteracting about 70% of the global mean temperature increase due to CO 2 and only 30% in ECHAM. While seeding impacts on mean precipitation were addressed in past studies, we are the first to analyze extreme precipitation responses to cirrus seeding. Seeding decreases the frequency of the most extreme precipitation globally. However, the extreme precipitation events occur more frequently in the Sahel and Central America, following the mean precipitation increase due to a northward shift of the Intertropical Convergence Zone. In addition, we use a quadratic climate damage metric to evaluate the amount of CO 2 -induced damage cirrus seeding can counteract. Seeding decreases the damage by about 50% in ECHAM, and by 85% in CESM over the 21 selected land regions. Climate damage due to CO 2 increase is significantly reduced as a result of seeding in all of the considered land regions

Agronomy · Atmospheric sciences · Cirrus · Climate change · Climatology · Cloud seeding · Geography · Global warming · Meteorology · Precipitation · Radiative forcing · Seeding · Atmospheric aerosols and clouds · Atmospheric chemistry and aerosols · Climate Change and Geoengineering · Environmental Science · Geology

• Applying the multi-level perspective to climate geoengineering

  Open Access•Kyle Herman, B K Sovacool•Energy Research & Social Science•2024

  Añadir item

• Earth system interventions as technologies of the Anthropocene

  Open Access•Jesse L Reynolds•Environmental Innovation and…•2021

  Añadir item

• The Community Earth System Model

  James W Hurrell, M M Holland et al.•Bulletin of the American…•2013

  Añadir item

• Robust Responses of the Hydrological Cycle to Global Warming

  Isaac M Held, Brian J Soden•Journal of Climate•2006

  Añadir item

• The representative concentration pathways

  Open Access•Detlef P Van Vuuren, Jae Edmonds et al.•Climatic Change•2011

  Añadir item

• A multi-model assessment of regional climate disparities caused by solar geoengineering

  Open Access•Ben Kravitz, Douglas G MacMartin et al.•Environmental Research Letters•2014

  Añadir item

• Expert assessment concludes negative emissions scenarios may not deliver

  Open Access•Naomi E Vaughan, Clair Gough•Environmental Research Letters•2016

  Añadir item

• Modification of cirrus clouds to reduce global warming

  Open Access•David L Mitchell, William Finnegan•Environmental Research Letters•2009

  Añadir item

• Early onset of significant local warming in low latitude countries

  Open Access•Irina Mahlstein, Reto Knutti et al.•Environmental Research Letters•2011

  Añadir item