{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"2c9e0e54b989d6f9e4da8c799c1113609649610959b6bfb955b0ffe548013376","created":"2026-10-03T07:18:03Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"a829498659733f295f8eec2d082d0394fccc82ceea0706c0b4795335ad69d440","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"earth.venus-divergence.superrotation","kind":"phenomenon","literature_status":"partially-resolved","n":"1","parents":[],"plain":"The solid body of Venus turns once every 243 Earth days, but its clouds circle the planet in about 4 days, roughly sixty times faster. Which waves and eddies keep feeding spin into the atmosphere is unresolved.","posed_since":"","precise":"At cloud-top altitude (about 70 km) zonal winds reach about $1e4\\,\\mathrm{cm}/\\mathrm{s}$, roughly 60 times the equatorial surface rotation speed. Identify the angular-momentum balance that maintains this superrotation: thermal tides driven by solar heating of the cloud layer, the Gierasch-Rossow-Williams mechanism (mean meridional circulation plus equatorward eddy transport by planetary waves and barotropic instability), or other waves, with their contributions as a function of altitude. An answer is a quantitative angular-momentum budget, from observations or from a general circulation model, that reproduces the observed wind profile and its variability.","problem_ref":null,"references":"","settled_by":"Cloud-tracked and radio-occultation wind and temperature fields that resolve tidal and eddy momentum fluxes at several altitudes, matched by a general circulation model.","status_note":"Akatsuki cloud tracking (Horinouchi and coauthors, Science 2020, https://doi.org/10.1126/science.aaz4439) found thermal tides accelerate the equatorial cloud-top flow while waves and turbulence decelerate it; the full vertical budget remains open.","title":"What maintains the superrotation of Venus's atmosphere?","topic_ref":"2d563ce4d5d56d2365b73e28ad4b61c690ba87ce44cf2790d484e63faf665432"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"8dfe37c2183b8048b4eae2bf621363c92beef4f301b205cde6346a65fc95156e","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"8e793304aaa47bd88e4cff0ebd55b9a3474614d28e5b545c3f3b2ed32f3ad4ef","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"qja__agkvcCxgQ1P8sDGuzIwEWT815e49fSwRXAnFFGYkfWnMgKxKDMjhCPRo2_SCkmehCqzchaVk045h7ppBw"},"schema":"pubphys.envelope/1"},"record_hash":"8dfe37c2183b8048b4eae2bf621363c92beef4f301b205cde6346a65fc95156e","leaf_index":1381}