{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"c5644424a1d189c74c4f6954c02d69232fc99f9eb8a1a1e5bfeee4aff3fa24b1","created":"2026-10-03T07:18:02Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"fff7acff799a1349327b58b0e7ce298636268a78d275df60e955306c20a0b5fb","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"earth.climate-sensitivity.albedo-2023","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"In 2023 Earth reflected less sunlight than ever measured, mainly because of fewer low clouds, which added to the record heat. Whether this came from cleaner ship exhaust, natural swings, or a cloud response to warming is unclear.","posed_since":"","precise":"Satellite radiation budgets show a record-low planetary albedo in 2023 driven by reduced low cloud cover, contributing roughly 0.2 K to the global temperature anomaly (Goessling and coauthors, 2024). Separate the contributions of reduced sulfate aerosol (including 2020 shipping fuel rules), internal variability and a low-cloud feedback. An answer is a quantitative attribution with uncertainties.","problem_ref":null,"references":"","settled_by":"Ensemble attribution experiments with observed aerosol emissions and nudged circulation compared against satellite cloud and radiation records.","status_note":"Diagnosed in a 2024 study (arXiv:2405.19986) with the cause left open; a 2025 comment debated the interpretation.","title":"What caused Earth's record-low reflectivity in 2023?","topic_ref":"9825ae6297d7163c036f24262af4c46a63835d02712ce8b2f6de7b3820ec47e6"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"d55b86723dd8d32f417e0f8b80671a58de65648607d8187314a0729cb7727d93","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"7b4576210e1948f6f9a19536f7c5146eecac374419027af86f7cb74bbc60f3bb","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"G62mktEZyna-f92kKfCBDpEHoNmpY3Kg0YTeQniiMt06cZ75_7p8p21afTxRRJF5l2Af8v_6905optKoO4-8Aw"},"schema":"pubphys.envelope/1"},"record_hash":"d55b86723dd8d32f417e0f8b80671a58de65648607d8187314a0729cb7727d93","leaf_index":1296}