Impact of Indian and East Asian Summer Monsoons on the Diurnal Temperature Range of the Low-Latitude Highlands of China in the Rainy Season

Abstract

This study investigates the impact of the Indian and East Asian summer monsoons on the diurnal temperature range (DTR) in the low-latitude highlands of China (CLLH) based on in-situ DTR observations, ERA5 reanalysis data, and numerical simulations. Diagnoses indicate that the DTR in the CLLH shows a significant positive correlation with the Indian summer monsoon (ISM), while a negative correlation with the East Asian summer monsoon (EASM). When a strengthened ISM occurs with a weakened EASM, an anomalous anticyclonic circulation with downward motion is excited over the CLLH. This anomalous circulation pattern increases the DTR in the rainy season by reducing the medium and high cloud cover in the CLLH. When a weakened ISM with a strengthened EASM decreases the DTR over the CLLH in the rainy season. Numerical experiments help to verify this crucial physical process linking the variability of the ISM and EASM with the DTR in the CLLH. The model results further indicate that the covariability of ISM and EASM contributes most to the variability of the rainy season DTR in the CLLH, followed by the individual variability of the EASM, and the smallest contribution to the rainy season DTR in the CLLH is the individual variability of the ISM.

Spatial–Temporal Variations in Temperature and Precipitation Extremes during 1960–2019 in Guizhou Province, China

“…Th topography over Guizhou Province increases from east to west and ranges from 121 m t 2887 m, with an average altitude of 1100 m. Carbonate rocks in the karst region are widel distributed and account for 62% of the total area in Guizhou Province [37,38]. The regio is a typical subtropical humid monsoon climate area, not merely affected by eastern Asia monsoon, but the Indian monsoon [39]. The mean annual temperature is 15 °C and annua cumulative precipitation is about 1200 mm, mostly occurring during April-Septembe Guizhou Province has suffered from a variety of extreme climate and weather disaster such as flooding, hailstones, freezing rain, drought, and rainstorms.…”