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Background Antimicrobial resistance (AMR) is an escalating global health crisis being worsened by climate change. Studies of temperature–AMR associations remain limited by geographic scope, time frames and linear approaches. We aimed to identify temperature thresholds where AMR dynamics shift across pathogen–drug combinations, periods and socioeconomic contexts.Methods We analysed data from 56 countries and territories over 24 years (1999–2022), focusing on six WHO-designated ‘critical’ antibiotic-resistant pathogens. Using segmented regression models with mean ambient temperature as the primary independent variable, we divided the study period into three intervals (1999–2006, 2007–2014, 2015–2022) and incorporated 16 socioeconomic and environmental covariates. Model robustness was validated through bootstrap cross-validation with 1000 resamples.Findings We identified distinct temperature association thresholds for each pathogen–drug combination (5.7°C–18.4°C). Below these thresholds, resistance rates consistently decreased with rising temperatures; above thresholds, responses varied by phenotype and time period. For third-generation cephalosporin-resistant Escherichia coli, each 1°C rise above 16.5°C corresponded to a 0.46% increase (95% CI 0.28% to 0.65%; p<0.001) during 1999–2006, a 0.11% decrease (95% CI −0.17% to −0.06%; p<0.001) during 2007–2014 and a 0.18% increase (95% CI 0.11% to 0.25%; p<0.001) during 2015–2022. The Corruption Perception Index showed consistent negative associations with resistance rates, particularly for carbapenem-resistant Acinetobacter baumannii (β=−1.40, p<0.001).Interpretation Phenotype-specific temperature association thresholds provide descriptive, hypothesis-generating reference points for understanding how AMR burden varies along the global temperature gradient. The observed temporal heterogeneity suggests complex patterns requiring long-term monitoring and climate-adaptive AMR control strategies considering both phenotype-specific temperature sensitivities and socioeconomic contexts.