Elevation-Dependent Trend in Diurnal Temperature Range in the Northeast China during 1961–2015

Abstract

The diurnal temperature range (DTR) is considered a signature of observed climate change, which is defined as the difference between the maximum (Tmax) and minimum temperatures (Tmin). It is well known that the warming rate of mean temperature is larger at high elevations than at low elevations in northeast China. However, it is still uncertain whether DTR trend is greater at high elevations. This study examined the spatiotemporal variation in DTR and its relationship with elevation in northeast China based on data from 68 meteorological stations from 1961 to 2015. The results show that there was a significant declining trend (0.252 °C/decade) in DTR from 1961 to 2015 due to the fact that Tmin increased at a faster rate than Tmax. Seasonally, DTR in northeast China showed a decreasing trend with the largest decrease rate in spring (−0.3167 °C/decade) and the smallest decrease rate in summer (−0.1725 °C/decade). The results of correlation analysis show that there was a significant positive correlation between the annual DTR trend and elevation in northeast China. This is due to the fact that increasing elevation has a significant warming effect on Tmax. Seasonally, there were significant positive correlations between the DTR trend and elevation in all seasons. The elevation gradient of DTR trend was the greatest in winter (0.392 °C/decade/km) and the lowest in autumn (0.209 °C/decade/km). In spring, summer, and autumn, increasing elevation has a significant warming effect on Tmax, leading to a significant increase of the DTR trend with increasing elevation. However, in winter, increasing elevation has a significant cooling effect on Tmin, resulting in a significant increase of the DTR trend with increasing elevation.

Long‐Term Variability and Trends in Snow Depth and Cover Days Throughout Iranian Mountain Ranges

“…Previous studies concluded that DTR decreased in most parts of the world (Braganza et al., 2004; Zhang et al., 2021), although increased in some areas (Libanda et al., 2019). In several cases, a combination of both positive and negative trends has been observed (Liu et al., 2021; Nawaz et al., 2019; Sun et al., 2019).…”

“…Recent findings suggest that the increase in air temperature is likely to continue in the future decades in Iran, which could contribute to snow melting and more evaporation, negatively impacting water resources in the country, which is already facing a water crisis (Karimi Alavijeh et al., 2021). Regarding changes in surface air temperature based on 13 in situ stations, however, DTR generally provides more information on climate change than T mean because it is related to T max and T min as well as it is more sensitive to radiation energy balance change (Braganza et al., 2004; Zhang et al., 2021). Changes in DTR can also influence the start of the growing season (Huang et al., 2020), mortality and morbidity (Davis et al., 2020), and cloud cover (Libanda et al., 2019).…”

Discontinuity of Diurnal Temperature Range Along Elevated Regions

“…Most previous studies have focused on how the DTR varies over time (Easterling et al., 1997; Jaagus et al., 2014; Kumar et al., 1994; Pepin et al., 2019; Shekhar et al., 2018; Shen et al., 2014; Vose et al., 2005; Zhang et al., 2021). Comparatively, the trends of DTR in altitude were not consistent both in the open field (Gheyret et al., 2020; Rapp & Silman, 2012) and understory (Rapp & Silman, 2012; Wang et al., 2017; Xue et al., 2020).…”

Short-term impact of diurnal temperature range on cardiovascular diseases mortality in residents in northeast China

“…However, the previous presented evidence suggesting on the relationship between CVD and DTR was limited, especially in northeast China where is cold weather in winter and poorer medical infrastructures. In addition, by analyzing the relationship between DTR and elevation, the existing research showed that the DTR or DTR change in northeast China is different from that in the other regions of China 28 . In Zhang et al 28 , the study results showed that in northeast China, increasing elevation has a warm effect on DTR, leading to a significant increase of the DTR trend.…”

“…In addition, by analyzing the relationship between DTR and elevation, the existing research showed that the DTR or DTR change in northeast China is different from that in the other regions of China 28 . In Zhang et al 28 , the study results showed that in northeast China, increasing elevation has a warm effect on DTR, leading to a significant increase of the DTR trend. Thus, we focused on the city of northeast China-Hulunbuir where is area with larger diurnal temperature difference and higher CVD mortality.…”