Over the last five decades since the first Earth Day, the JIH and environmental history, one newborn and the other already well established, have evolved within the broader context of climate change and the human reaction to it. Two of the JIH's special issues, "History and Climate" (1980) and the "Little Ice Age: Climate and History Reconsidered" (2014), serve as bookends for an examination of how the journal responded to the latest scientific and historical findings. No other area of research requires interdisciplinary methods from so many branches of learning as does environmental history. Articles published in the JIH during the 1980s and thereafter reveal the advances in both climate research and environmental history that testify to the journal's influence. All signs point to a vigorous and continuing role for the JIH in keeping these subjects at the forefront of an interdisciplinary endeavor ranging across the entire planet and its deep history.