Abstract
Since the 1950s, the East Asian diurnal temperature range (DTR) defined as the difference between the daily maximum (Tmax) and minimum temperatures (Tmin) has gradually decreased. Precipitation changes have often been cited as a primary cause of the change. However, the East Asian DTR change before 1950 and its relationship with precipitation remain unclear. Here, we mainly use a newly developed China Meteorological Administration-Land Surface Air Temperature dataset v1.1 to examine the climatological patterns and long-term trends of the DTR in East Asia from 1901 to 2018, and its relationship with precipitation. 1951–2018 mean annual DTR averaged over East Asia is approximately 10.0°C. East Asian DTR changes during 1901–2018 show two distinct characteristics. First, the DTR decrease significantly by about 0.60 ℃ during 1901–2018, and the decrease rate in the second half of the 20th century (by ~ 0.53 ℃) is significantly larger than that over the rest of the Northern Hemisphere and the global land due to rapid urbanization over East Asia. Second, before the 1950s, the DTR in East Asia shows a significant non-linear increase, while there are substantial differences in different latitude zones. The middle and high latitudes show the fluctuating rise and decline, respectively. Additionally, we find that the spatial pattern of long-term DTR change shows a significant negative correlation with mean precipitation patterns except in arid and semi-arid areas during 1901–2018. Besides, the decreasing trend of DTR is gradually become smaller from arid regions to humid regions during 1901–2018, mainly due to the difference between Tmax and Tmin warming rate is gradually become smaller.