{"corpus_id":140627446,"paper_sha":"879fb17bdd353fd6de9c28219b27619b841e3567","doi":"10.1029/1999JD901006","arxiv_id":null,"pmid":null,"pmcid":null,"mag_id":2082665463,"dblp_id":null,"acl_id":null,"title":"Three-dimensional climatological distribution of tropospheric OH: Update and evaluation","year":2000,"publication_date":"2000-04-16","venue":"","journal":{"name":"Journal of Geophysical Research","pages":"8931-8980","volume":"105"},"journal_issn":null,"journal_title":null,"publication_types":[],"pubmed_pub_types":null,"s2_fields_of_study":["Physics","Environmental Science"],"reference_count":204,"citation_count":839,"influential_citation_count":48,"is_open_access":true,"arxiv_categories":null,"arxiv_license":null,"arxiv_journal_ref":null,"mesh_headings":null,"chemicals":null,"comments_corrections":null,"source_flags":1,"s2_open_access_pdf_url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1029/1999JD901006","s2_open_access_landing_url":"https://www.semanticscholar.org/paper/501a3fb84643b85b14b906b9b6cd6d0aa6f676cc","s2_open_access_license":null,"s2_open_access_status":"BRONZE","pmc_open_access_pdf_url":null,"pmc_open_access_landing_url":null,"pmc_open_access_license":null,"pmc_open_access_status":null,"unpaywall_open_access_pdf_url":null,"unpaywall_open_access_landing_url":null,"unpaywall_open_access_license":null,"unpaywall_open_access_status":null,"abstract":"A global climatological distribution of tropospheric OH is computed using observed distributions of O 3 , H 2 O, NO t (NO 2 +NO + 2N 2 O 5 + NO 3 + HNO 2 +HNO 4 ), CO, hydrocarbons, temperature, and cloud optical depth. Global annual mean OH is 1.16×10 6 molecules cm −3 (integrated with respect to mass of air up to 100 hPa within ±32° latitude and up to 200 hPa outside that region). Mean hemispheric concentrations of OH are nearly equal. While global mean OH increased by 33% compared to that from Spivakovsky et al. [1990], mean loss frequencies of CH 3 CCl 3 and CH 4 increased by only 23% because a lower fraction of total OH resides in the lower troposphere in the present distribution. The value for temperature used for determining lifetimes of hydrochlorofluorocarbons (HCFCs) by scaling rate constants [ Prather and Spivakovsky , 1990] is revised from 277 K to 272 K. The present distribution of OH is consistent within a few percent with the current budgets of CH 3 CCl 3 and HCFC‐22. For CH 3 CCl 3 , it results in a lifetime of 4.6 years, including stratospheric and ocean sinks with atmospheric lifetimes of 43 and 80 years, respectively. For HCFC‐22, the lifetime is 11.4 years, allowing for the stratospheric sink with an atmospheric lifetime of 229 years. Corrections suggested by observed levels of CH 2 Cl 2 (annual means) depend strongly on the rate of interhemispheric mixing in the model. An increase in OH in the Northern Hemisphere by 20% combined with a decrease in the southern tropics by 25% is suggested if this rate is at its upper limit consistent with observations of CFCs and 85 Kr. For the lower limit, observations of CH 2 Cl 2 imply an increase in OH in the Northern Hemisphere by 35% combined with a decrease in OH in the southern tropics by 60%. However, such large corrections are inconsistent with observations for 14 CO in the tropics and for the interhemispheric gradient of CH 3 CCl 3 . Industrial sources of CH 2 Cl 2 are sufficient for balancing its budget. The available tests do not establish significant errors in OH except for a possible underestimate in winter in the northern and southern tropics by 15–20% and 10–15%, respectively, and an overestimate in southern extratropics by ∼25%. Observations of seasonal variations of CH 3 CCl 3 , CH 2 Cl 2 , 14 CO, and C 2 H 6 offer no evidence for higher levels of OH in the southern than in the northern extratropics. It is expected that in the next few years the latitudinal distribution and annual cycle of CH 3 CCl 3 will be determined primarily by its loss frequency, allowing for additional constraints for OH on scales smaller than global.","claims":[{"public_id":"cl_e4f48cc3eef89f72b0e73c5039c49d9c","status":"active","text":"A global climatological distribution of tropospheric OH was computed from observed distributions of O3, H2O, NOt, CO, hydrocarbons, temperature, and cloud optical depth.","confidence":0.96,"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/claims/cl_e4f48cc3eef89f72b0e73c5039c49d9c"},{"public_id":"cl_552908d9c00ba0a4dcd89126b2cc7893","status":"active","text":"Available tests do not establish significant errors in OH except for possible winter tropical underestimates and a southern extratropical overestimate.","confidence":0.9,"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/claims/cl_552908d9c00ba0a4dcd89126b2cc7893"},{"public_id":"cl_0ddc2f078dd9df596ade6df4d201ac36","status":"active","text":"Global annual mean OH is 1.16×10^6 molecules cm−3, and mean hemispheric concentrations of OH are nearly equal.","confidence":0.97,"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/claims/cl_0ddc2f078dd9df596ade6df4d201ac36"},{"public_id":"cl_f1202ec2aa04d788338c1659b8fd254b","status":"active","text":"Global mean OH increased by 33% relative to Spivakovsky et al. [1990], while mean loss frequencies of CH3CCl3 and CH4 increased by only 23%.","confidence":0.95,"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/claims/cl_f1202ec2aa04d788338c1659b8fd254b"},{"public_id":"cl_bb8d258e9c76bf7dc90c638972eafdea","status":"active","text":"The distribution of OH yields lifetimes of 4.6 years for CH3CCl3 and 11.4 years for HCFC-22 when accounting for specified stratospheric, ocean, or stratospheric sinks.","confidence":0.94,"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/claims/cl_bb8d258e9c76bf7dc90c638972eafdea"}],"concepts":[{"public_id":"co_00b81c72443c62a286345364a75b5ab5","status":"active","name":"global climatological distribution of tropospheric OH","description":"A three-dimensional climatological representation of hydroxyl radical concentrations in the troposphere.","types":["atmospheric distribution"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_00b81c72443c62a286345364a75b5ab5"},{"public_id":"co_08832baca49420e37e8a42a2b06e3b5f","status":"active","name":"mean hemispheric concentrations of OH","description":"Average OH concentrations compared between the Northern and Southern Hemispheres.","types":["measurement"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_08832baca49420e37e8a42a2b06e3b5f"},{"public_id":"co_0f4360c2ad53cd6028d942bda448c20b","status":"active","name":"global annual mean OH","description":"The globally averaged annual concentration of tropospheric hydroxyl radicals reported in the abstract.","types":["measurement"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_0f4360c2ad53cd6028d942bda448c20b"},{"public_id":"co_20c83e1a87601632a51f7332115e0762","status":"active","name":"available tests","description":"Comparisons with observed trace gases used to evaluate possible errors in the OH distribution.","types":["evaluation evidence"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_20c83e1a87601632a51f7332115e0762"},{"public_id":"co_2667cbab620cf8b397d06ecf3e526962","status":"active","name":"HCFC-22 lifetime","description":"The atmospheric lifetime of hydrochlorofluorocarbon-22 after allowing for the stratospheric sink.","types":["chemical lifetime"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_2667cbab620cf8b397d06ecf3e526962"},{"public_id":"co_61e60d7af5b09a126ae7743fdca987d5","status":"active","name":"observed distributions","description":"Measured spatial fields of atmospheric inputs used to compute the OH distribution.","types":["input data"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_61e60d7af5b09a126ae7743fdca987d5"},{"public_id":"co_680465fc792957f6ee2076a16e858a97","status":"active","name":"global mean OH","description":"The worldwide mean concentration of hydroxyl radicals used for comparison with a prior distribution.","types":["measurement"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_680465fc792957f6ee2076a16e858a97"},{"public_id":"co_68e79371f44d22b493fdc92110290ab5","status":"active","name":"southern extratropical OH overestimate","description":"A possible high bias in OH levels in the southern extratropics.","types":["model error"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_68e79371f44d22b493fdc92110290ab5"},{"public_id":"co_6cb8cb811dd5e031ac704b379a14c6b7","status":"active","name":"tropospheric OH","description":"Hydroxyl radicals located in the troposphere and evaluated as an atmospheric oxidant.","types":["chemical species"],"aliases":["OH"],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_6cb8cb811dd5e031ac704b379a14c6b7"},{"public_id":"co_943646680ab87c76fce6048324a680bf","status":"active","name":"cloud optical depth","description":"A cloud property used as one of the observed inputs for computing tropospheric OH.","types":["atmospheric variable"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_943646680ab87c76fce6048324a680bf"},{"public_id":"co_abe1792491c5fe14c970acc955a198ea","status":"active","name":"CH3CCl3 lifetime","description":"The atmospheric lifetime of methyl chloroform after including stratospheric and ocean sinks.","types":["chemical lifetime"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_abe1792491c5fe14c970acc955a198ea"},{"public_id":"co_b67c567dcfdcfff5937850e3c707a491","status":"active","name":"Spivakovsky et al. [1990]","description":"A prior OH distribution used as a reference comparison for the updated calculation.","types":["reference distribution"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_b67c567dcfdcfff5937850e3c707a491"},{"public_id":"co_ebb7c736ee92cdafdc1bf855049602c6","status":"active","name":"winter tropical OH underestimate","description":"A possible low bias in OH levels during winter in the northern and southern tropics.","types":["model error"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_ebb7c736ee92cdafdc1bf855049602c6"},{"public_id":"co_f54870963889ff371a97e4977964ece9","status":"active","name":"mean loss frequencies of CH3CCl3 and CH4","description":"Average atmospheric removal frequencies for methyl chloroform and methane by reaction with OH.","types":["chemical loss metric"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_f54870963889ff371a97e4977964ece9"},{"public_id":"co_f828ddf90861dbcd2b1aae04bcfe1056","status":"active","name":"distribution of OH","description":"The spatial arrangement of hydroxyl radical concentrations used to evaluate atmospheric chemical lifetimes.","types":["atmospheric distribution"],"aliases":[],"contributors":[{"id":136,"public_id":"3c2apqe3ut","public_label":"Anonymous (3c2apqe3ut)","roles":["extraction"],"url":"https://sah.borca.ai/u/3c2apqe3ut"},{"id":2,"public_id":"4715169a40","public_label":"AK (4715169a40)","roles":["review"],"url":"https://sah.borca.ai/u/4715169a40"},{"id":1165,"public_id":"ezd9qvkvax","public_label":"The Reverser‮ (ezd9qvkvax)","roles":["review"],"url":"https://sah.borca.ai/u/ezd9qvkvax"}],"url":"https://sah.borca.ai/concepts/co_f828ddf90861dbcd2b1aae04bcfe1056"}],"external_ids":{"DOI":"10.1029/1999JD901006","ArXiv":null,"PubMed":null,"PubMedCentral":null,"MAG":2082665463,"DBLP":null,"ACL":null},"open_access":{"is_open_access":true,"pdf_url":"https://onlinelibrary.wiley.com/doi/pdfdirect/10.1029/1999JD901006","landing_url":"https://www.semanticscholar.org/paper/501a3fb84643b85b14b906b9b6cd6d0aa6f676cc","source":"semantic_scholar","pdf_url_source":"semantic_scholar_open_access_pdf","license":null,"status":"BRONZE","reason":null},"reference_availability":{"status":"available","references_indexed":true,"full_text_available":false,"full_text_source":null,"count_basis":"semantic_scholar_metadata","extraction_status":"not_applicable","reason":null},"source":{"provider":"episteme2","base_corpus":"semantic_scholar_dump","freshness_mode":"unknown","basis":["semantic_scholar_metadata","postgres_metadata"],"limits":["paper metadata is based on indexed upstream scholarly datasets","claims and concepts are available only for extracted papers","absence of claims or concepts means no extracted graph data is available in this response"],"status":"available","degraded":false,"degraded_reasons":[],"diagnostics":{"status":"available","degraded":false,"degraded_reasons":[],"metadata_status":"available","graph_status":"available","abstract_status":"available"},"source_flags":1},"paper_id":632018,"paper_uid":"1d181cff-219a-4ef5-85cd-9dffb9f47fd4","canonical_identity":{"paper_id":632018,"paper_uid":"1d181cff-219a-4ef5-85cd-9dffb9f47fd4","identity_status":"available","lookup_basis":"semantic_scholar_external_id","compatibility_path":"corpus_id"},"url":"https://sah.borca.ai/papers/140627446"}