Climatology of the Soil Surface Diurnal Temperature Range in a Warming World: Annual Cycles, Regional Patterns, and Trends in China

Abstract

The soil surface diurnal temperature range (SSDTR), reflecting the synchronicity of changes in the daily extremes of soil surface temperatures, provides an important and sensitive indicator of climate change. The climatology of SSDTR and its trends have a strong connection with the land surface energy budget, but this has received little notice up to now. Our research examines the spatial‐temporal characteristics of the annual cycle of SSDTR and its connection with other climate variables in China. The results demonstrate that the annual SSDTR curve changes gradually across space, with both regional and zonal characteristics. The shape of the annual SSDTR curve varies among regions. While it shows consistently strong positive associations with solar irradiance across China, a strong negative association with relative humidity is evident only in the dry western regions and the connection with relative humidity progressively decouples as we move toward the moist eastern regions. Atmospheric circulation affects SSDTR indirectly through derived changes in the seasonal cycles of moisture and solar irradiance. This produces a zonal character of the SSDTR annual curve in the east, while in the west the positive land‐atmosphere feedback under low moisture conditions is associated with a regional character. The magnitude of the annual cycle of SSDTR is large compared with temporal change, contributing to the generally stable nature of the cycle under global warming conditions.

Spatiotemporal variation characteristics of hourly soil temperature in different layers in the low-latitude plateau of China

“…A change in soil temperature might alter the physical properties of soil, which could then impart substantial impact on the physical, chemical, and biological processes occurring both above and below ground (Davidson and Janssens., 2006;Giardina et al, 2014;Hartley., 2014;Zhang et al, 2016;Li et al, 2022). Understanding the variations of soil temperature is of Frontiers in Environmental Science frontiersin.org great importance for assessing energy exchange between the soil and the atmosphere in relation to climate change (Du et al, 2017;Shen et al, 2020;Liu et al, 2022;Oogathoo et al, 2022;Song et al, 2022). This study found a significant seasonal pattern contrary to the variation of average shallow and deep soil temperature, i.e., it decreases (increases) with increasing soil depth in spring and summer (autumn and winter) at 00:00-23:00.…”

“…The structure, function, productivity, and stability of an ecosystem largely depend on the soil temperature regime because soil temperature affects the germination of seedling emergence, early developmental and growth processes, tree species distribution and forest composition, and crop yield by changing the carbon and nutrient cycles, fertility, and productivity of the soil (Linderholm., 2006;Curiel et al, 2007;Kurylyk et al, 2014;Zhang et al, 2016;Hu et al, 2019;Oogathoo et al, 2022). Meanwhile, as important thermal and hydrological factors of the ground at any given location, soil temperature and soil moisture respond quickly to the effects of climate change and interact with the overlying atmosphere through the surface energy, water balance, and carbon cycles, substantially promoting feedback to regional climate (Albergel et al, 2015;Zhu et al, 2021;Liu et al, 2022). Soil temperature is also an important indicator of climate change and a critical parameter in numerical weather forecasting and climate prediction (Holmes et al, 2008;Qian et al, 2011;Albergel et al, 2015;Li et al, 2022;Song et al, 2022).…”

Microclimate Impacts of Land Cover Types in Halu Oleo University Botanical Garden and Its Surroundings

“…The highest (maximum) air temperature measurements in the three land covers occurred during the daytime due to surface heating by high light intensity. According to Liu et al (2022) and Koesmaryono and Askari (2023), fluctuations in air temperature (and soil temperature) are closely related to the energy exchange process that takes place in the atmosphere due to sunlight, where the absorption of solar radiation energy will cause the air temperature to increase. It is further explained that the maximum daily air temperature is reached sometime after the maximum light intensity is reached when the light beam falls perpendicularly at midday.…”