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Abstract The western Pacific warm pool (WPWP) is the heat engine of the global climate system delivering vast amounts of heat and moisture to the atmosphere. Controls on regional convection, however, are numerous, making it difficult to simulate past and future changes in WPWP hydroclimate with confidence. Here, we synthesize new and previously available precipitation sensitive records from the WPWP spanning the last and present interglacial periods. We find two primary modes of rainfall variability, both driven by precession forcing, that are common to both interglacial periods: (a) a contraction of the tropical rain band across the interglacial and (b) a mid‐interglacial strengthening of the Pacific Walker Circulation (PWC). We further demonstrate that while the amplitude of the change in seasonal insolation across the Holocene is far lower than during the LIG due to the low eccentricity state of Earth's orbit, the response of regional rainfall is comparable during both interglacials, indicating a nonlinear response to the insolation forcing. Finally, we suggest an enhanced sensitivity of the PWC to non‐insolation climate forcing, including greenhouse gases and sea level change, under strongly reduced boreal fall insolation as observed during the late Holocene and late LIG. 

The North Atlantic and Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the Northern Hemisphere overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water (NAW) transporting heat, salt, and moisture to the Northern Hemisphere has been indicated as one of the main forcing mechanisms for the onset of Northern Hemisphere glaciation. NAW controls the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of high insulation and/or high atmospheric CO2 content is still largely unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution continuous expanded sedimentary sequences identified on the western continental margin of Svalbard and eastern side of the Fram Strait, along the main pathway and northern penetration of the NAW flowing into the Arctic Ocean. The area around Svalbard is very sensitive to climatic variability and can be considered a sentinel of climate change. Furthermore, the reconstruction of the dynamic history of the marine-based paleo-Svalbard–Barents Sea Ice Sheet is important because it is considered the best available analog to the modern, marine-based West Antarctic Ice Sheet, for which the loss of stability is presently the major uncertainty in projecting future global sea level rise in response to the present global climate warming.