During the monitoring period from Jan 1st – 16th, 2021, the winter wheat in northwest China, North China and Huanghuai entered the overwintering stage, while in Jianghuai, Jianghan and southwest China it was mostly in tillering stage. And it was in jointing stage in Yunnan and south of Sichuan.
In terms of meteorological conditions, affected by the cold air mass, although in early January the temperature was 2-5℃ lower than average of the same period in most parts of the country, 1-1.5℃ lower in Sichuan and Yunnan province, it had little influence to the overwintering-stage wheat. The temperature increased gradually late and the sunshine hours were more than average, which contributed to an average crop condition of the winter wheat. In Chongqing, southwest of Hubei, southeast of Henan, northwest of Anhui, although the early temperature was 1-2℃ lower than average, it rose rapidly in the late. The significant precipitation, suitable moisture of soil and the above-average radiation were beneficial to the growth of winter wheat and led to an above-average crop condition. In the meanwhile, in Shandong, middle and north of Jiangsu, the temperature was about 3℃ lower than average and the rainfall recorded was lower than average of the same period, which was harmful to the growth of winter wheat and other crops.
Figure 1: NDVI departure from 5 years average (2021.1.1 - 2021.1.16)