In a study published in the Proceedings of the National Academy of Sciences (PNAS), Weldeab and co-authors present evidence for massive methane hydrate destabilization during a period called the Eemian when the global climate was, on average,  warmer by 1-1.5 °C than today. Weldeab et al  reconstructed an exceptionally strong warming of the tropical Atlantic waters at intermediate depth (below the surface water 500-1300 m) and uncovered isotopic fingerprints of methane release across the water column of 1300 meters. The authors of the article attribute their observation to climatic feedback processes, involving climate warming,  meltwater-induced perturbation of ocean circulation, a strong warming of intermediate water warming that exceeded the methane hydrate stability that impinge on methane hydrate-bearing sediments. See the original paper for more details: https://www.pnas.org/doi/full/10.1073/pnas.2201871119