{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"78d1c4a570adabe22e5f0670276caa8ac1d524277f25c990d038341e3696e771","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b","e3bbdb80b1761eb35e366cc44246dc1765a31295fd901b3efc88ca639aedd406"],"salt":"058f6f61855d5d7ae763b4de2b12f58b0ebee360408631891dd465d9ed8c10a2","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"earth.climate-sensitivity.anvil-feedback","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"High, thin anvil-shaped clouds spread out from tropical thunderstorms and trap heat. If they shrink with warming, more heat escapes to space, a cooling effect called the 'iris' hypothesis, but its size is debated.","posed_since":"","precise":"The tropical anvil cloud area feedback was assessed at about $-2 \\times 10^{2} \\pm 2 \\times 10^{2}\\,\\mathrm{erg}/(\\mathrm{s}\\,\\mathrm{cm}^2\\,\\mathrm{K})$ (Sherwood and coauthors 2020), while the iris hypothesis (Lindzen and coauthors 2001) argued for a much more negative value. Determine the global anvil-area feedback and its mechanism (stability iris, changes in convective aggregation, anvil lifetime and microphysics) with uncertainty below about $10^{2}\\,\\mathrm{erg}/(\\mathrm{s}\\,\\mathrm{cm}^2\\,\\mathrm{K})$.","problem_ref":"e3bbdb80b1761eb35e366cc44246dc1765a31295fd901b3efc88ca639aedd406","references":"","settled_by":"Cloud-resolving simulations under warming with resolved anvil microphysics, validated against satellite relations between anvil area, cloud radiative effect and surface temperature.","status_note":"McKim, Bony and Dufresne (Nature Geoscience 2024, https://doi.org/10.1038/s41561-024-01414-4) argued that physical and observational constraints imply a weak anvil-area feedback.","title":"How much do tropical anvil clouds shrink as Earth warms?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"1016521381b963b500a22fa9daafb1e0521c9a61218c2484eae1160918062419","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"2fecb12d2fb7ebccc6a4196d0f92a78ecb8ef9d5705762603b538d783581c9b0","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"15gkJjaNlnhH5H_CvAUcrfH2jzrs6HrbTsFqmuQM9PW23BpIpOSvHPboCeQCQVcB6oyG7fP_8YbApLI5ADUoDA"},"schema":"pubphys.envelope/1"},"record_hash":"1016521381b963b500a22fa9daafb1e0521c9a61218c2484eae1160918062419","leaf_index":3172}