Coupling of Soil Moisture and Air Temperature from Multiyear Data During 1980–2013 over China

Abstract

Soil moisture is an important parameter in land surface processes, which can control the surface energy and water budgets and thus affect the air temperature. Studying the coupling between soil moisture and air temperature is of vital importance for forecasting climate change. This study evaluates this coupling over China from 1980–2013 by using an energy-based diagnostic method, which represents the momentum, heat, and water conservation equations in the atmosphere, while the contributions of soil moisture are treated as external forcing. The results showed that the soil moisture–temperature coupling is strongest in the transitional climate zones between wet and dry climates, which here includes Northeast China and part of the Tibetan Plateau from a viewpoint of annual average. Furthermore, the soil moisture–temperature coupling was found to be stronger in spring than in the other seasons over China, and over different typical climatic zones, it also varied greatly in different seasons. We conducted two case studies (the heatwaves of 2013 in Southeast China and 2009 in North China) to understand the impact of soil moisture–temperature coupling during heatwaves. The results indicated that over areas with soil moisture deficit and temperature anomalies, the coupling strength intensified. This suggests that soil moisture deficits could lead to enhanced heat anomalies, and thus, result in enhanced soil moisture coupling with temperature. This demonstrates the importance of soil moisture and the need to thoroughly study it and its role within the land–atmosphere interaction and the climate on the whole.

Maximizing Temporal Correlations in Long-Term Global Satellite Soil Moisture Data-Merging

“…Within land-atmosphere interactions, soil moisture anomalies have been identified by many studies to play a key role by its control of the surface fluxes [1]. Additionally, existing studies have demonstrated the impact of soil moisture anomalies on extreme events such as heatwaves [2], floods [3] and droughts [4], as well as its importance in operational services and climate monitoring [5,6] at both regional and global scales. While they demonstrate the significant role of soil moisture, most of these studies rely on model simulations for which large uncertainties remain unexplored, thus, observations are necessary to understand the impact of soil moisture better.…”

K-Means and C4.5 Decision Tree Based Prediction of Long-Term Precipitation Variability in the Poyang Lake Basin, China

“…The climate signal during spring (March, April, and May) was used as a predictor to forecast the summer rainfall in sub-regions of the Poyang Lake Basin. In the land-atmosphere coupling domain, similar approaches have been widely used with a potential time-lag as a forecast indicator [42]. The 130-item climate index dataset was obtained by averaging the March, April, and May values of each index from the database, which provided a wide range of choices for selecting a potential index as a forecast indicator of Poyang Lake basin sub-regional precipitation variation.…”

Assessment of the impact of soil moisture on spring surface air temperature over the low‐latitude highlands of China

“…Recently, Gao et al (2018) found that the LLH is s a hot spot of land-atmosphere coupling over eastern China in spring. Additionally, the LLH is also a relatively strong SM-SAT coupling region in China during spring (Yuan et al, 2020). However, to what extent SM affects SAT in the LLH during spring and its possible mechanisms are yet to be studied, which are the main purpose of this research.…”