Paleosols preserved in the Red Clay depositional sequence of the Chinese Loess Plateau record information about vegetation and regional hydrology responses to global temperature variation throughout the late Miocene and Pliocene. Reconstructing spatial and temporal patterns of environmental change across the Loess Plateau from carbon isotopes of pedogenic carbonate (δ13Ccarb) is complicated because multiple factors affect δ13Ccarb values and higher resolution records do not exist along the northern margin of the Loess Plateau. To address these needs, we present paired carbon isotope records of pedogenic carbonate and occluded organic matter (δ13Corg) from 697 discrete nodules sampled from 119 different depths at the Jiaxian section, North Central China. Between 7.6 and 2.4 Ma, δ13Ccarb values increase by nearly 5‰, while δ13Corg values increase by 2.5‰. These increases are explained by a progressive decline in moisture availability through time, and there is no definitive evidence from these δ13C data for C4 vegetation at the Jiaxian site until after 3.6 Ma. Comparison of the Jiaxian record to other Loess Plateau sections reveals a consistent spatial gradient with δ13Ccarb values becoming higher and more variable to the N‐NW. Additionally, an independent index of monsoonal precipitation from a southern site corresponds to fluctuations in δ13Ccarb values at Jiaxian, while southern δ13Ccarb records remain more stable. These spatial patterns are explained by a progressive decline in moisture availability across the Loess Plateau through the Late Miocene and Pliocene, with δ13Ccarb values being more sensitive to moisture availability under consistently more arid conditions to the NW.

The Pliocene is considered an analog for future climate. Insolation is found the dominant forcing for Asian precipitation over the late Pliocene, evidenced by magnetic enhancement of Chinese loess caused by formation of nanometer‐scale ferrimagnetic grains during pedogenesis corresponding to high precipitation. However, lack of European loess limits understanding of Pliocene European climate. We identified likely similar magnetic enhancement mechanism between Pliocene alluvial sediments from Spain and Chinese loess despite different depositional settings. This provides an opportunity to improve understanding of Pliocene climate in Europe. Spectral analysis shows that European wet‐dry variations during the early Pliocene were forced by insolation and during the late Pliocene by both insolation and ice sheets development. During the Quaternary, in contrast, the forcing was dominantly from high latitude. These results demonstrate the importance of insolation during warm climates and the growing importance of ice sheets with global cooling in controlling Northern Hemisphere precipitation changes.

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