{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:10:25Z","timestamp":1785409825876,"version":"3.56.0"},"reference-count":65,"publisher":"National Academy of Sciences","issue":"20","license":[{"start":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T00:00:00Z","timestamp":1778457600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2026,5,19]]},"abstract":"<jats:p>\n                    Because of their impacts on droughts, famines, and floods, modes of climate variability can shape patterns of social instability. Yet the mechanisms linking climate variability to armed conflict remain contested, especially relative to the myriad sociopolitical and economic determinants of conflict. A key challenge is that most studies rely on coarse, state-level data and treat climatic teleconnections as invariant. As such, it is unknown whether there are distinct climate hazards that select for conflict risk; whether conflict scales with climate hazard exposure; and whether such associations exist for more regional forms of climate variability. Here we leverage empirical modeling using a high-resolution gridded dataset of armed conflicts and the natural experiment afforded by two major climate modes\u2014the El Ni\u00f1o\u2013Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD)\u2014to clarify how systematic hydroclimatic anomalies influence conflict emergence. Our results reveal the following: First, conflict risk heightens during El Ni\u00f1o, but ENSO-associated risk does not scale linearly with teleconnection strength; and, evidence for threshold behavior varies with spatial aggregation. Second, El Ni\u00f1o-related increases in conflict risk arise through its\n                    <jats:italic toggle=\"yes\">dry<\/jats:italic>\n                    teleconnections, with limited evidence for wet teleconnections. Finally, the more regionally confined IOD also influences conflict, with both positive and negative phases elevating risk in strongly teleconnected regions, namely the Horn of Africa and Southeast Asia. These results reveal that modes of climate variability can differentially shape conflict risk, offering insight into societies\u2019 vulnerabilities to natural climate fluctuations and, by extension, anthropogenic climate change.\n                  <\/jats:p>","DOI":"10.1073\/pnas.2532935123","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T19:10:31Z","timestamp":1778526631000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":2,"title":["Global and regional climate modes modulate armed conflict risk"],"prefix":"10.1073","volume":"123","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-7910-6192","authenticated-orcid":false,"given":"Tyler E.","family":"Bagwell","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/008zs3103","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Statistics, Rice University","place":["Houston"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sylvia G.","family":"Dee","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/008zs3103","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Earth, Environmental, and Planetary Sciences, Rice University","place":["Houston"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6048-3145","authenticated-orcid":false,"given":"Xinyue","family":"Luo","sequence":"additional","affiliation":[{"name":"Zhejiang Climate Center","place":["Hangzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Stravato","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/008zs3103","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of English, Rice University","place":["Houston"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Divya","family":"Saikumar","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/008zs3103","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of BioSciences, Rice University","place":["Houston"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9162-8212","authenticated-orcid":false,"given":"Frederi","family":"Viens","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/008zs3103","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Statistics, Rice University","place":["Houston"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8010-9983","authenticated-orcid":false,"given":"Bomi K.","family":"Lee","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/00fc1qt65","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Political Science, Bucknell University","place":["Lewisburg"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diana Z.","family":"O\u2019Brien","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01yc7t268","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Political Science, Washington University in St. Louis","place":["St. Louis"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2520-4555","authenticated-orcid":false,"given":"Justin S.","family":"Mankin","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/049s0rh22","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Geography, Dartmouth College","place":["Hanover"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2026,5,11]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.1080444"},{"key":"e_1_3_4_2_2","doi-asserted-by":"crossref","unstructured":"D. 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