Conflict and Climate Change in the Tropical Pacific

The authors note that it has been repeatedly suggested that in many parts of the world climate change has "encouraged conflict and territorialism," as this response, in their words, "serves as an immediate means of gaining resources and alleviating shortfalls," such as those that occur when the climate change is detrimental to agriculture and the production of food. To further investigate this hypothesis, Field and Lape compared "periods of cooling and warming related to hemispheric-level transitions (namely the Medieval Warm Period and the Little Ice Age)" in sub-regions of the Pacific with the occurrence of fortifications at the century-level." Results of their study revealed that "the comparison of fortification chronologies with paleoclimatic data indicate that fortification construction was significantly correlated with periods of cooling, which in the tropical Pacific is also associated with drying," noting that "the correlation was most significant in the Indo-Pacific Warm Pool, the Southwestern Pacific and New Zealand," where "people constructed more fortifications during periods that match the chronology for the Little Ice Age (AD 1450-1850)," as opposed to the Medieval Warm Period (AD 800-1300) when they say the Indo-Pacific Warm Pool was both warm and saline "with temperatures approximating current conditions (Newton et al., 2006)." Thus, Field and Lape's study provides more evidence for the gradually emerging fact that periods of greater warmth have generally led to more peaceful times throughout the world, while periods of lesser warmth have typically led to greater warfare.

Additional Reference
Newton, A., Thunnell, R. and Stott, L. 2006. Climate and hydrographic variability in the Indo-Pacific warm pool during the last millennium. Geophysical Research Letters 33: 10.1029/2006GL027234.