Over the past century, observed surface air temperatures (SATs) in the Arctic have exhibited substantial multidecadal variations: early-20th-century warming, mid-20th-century cooling, and subsequent ongoing enhanced warming (e.g.,

Instrumental records show that, except for a hiatus in the 1960s, the globally averaged surface air temperature (SAT) has risen rapidly in the latter half of the 20th century (IPCC, 2007(IPCC, , 2013. According to Bindoff et al. (2013), more than half of the global warming during this period can be explained by anthropogenic forcings. This warming is even more remarkable in the Arctic; Arctic SATs have risen more than twice as fast as the global average in recent decades. Satellite observations reveal that Arctic sea ice has rapidly decreased in all seasons accompanying a rapid Arctic temperature amplification in recent decades (e.g., Johannessen et al., 2004). The rapid warming and associated sea ice reduction are primarily due to enhanced anthropogenic effects (Gillett et al., 2008). Furthermore, specifically in the first half of the 20th century, instrumental records show that there was a significant warming period, called the early 20th century warming (ETCW), which was comparable to the present-day warming (

Changes in the hydrological cycle in the northern hemisphere (NH) have a significant socioeconomic impact. Thus, quantifying past changes and projecting future changes in this cycle are important. We analyzed the positive and negative multidecadal trends in the NH mean precipitation since the 1950s that were accurately reproduced by a state‐of‐the‐art Earth system model. Results showed that changes in the interhemispheric heat transport play a major role in the NH atmospheric heat budget, accounting for 59% of the negative‐to‐positive trend change in NH precipitation through a north–south shift in the tropical precipitation zone, and were strongly linked to Hadley circulation anomaly. The remaining 41% corresponded to changes in atmospheric cooling with small interhemispheric differences, which were primarily related to clear‐sky longwave radiation. These findings quantitatively agreed with the results from a multimodel analysis.