4.1 Overview

Agroclimatic conditions were mostly unfavourable in China between October 2017 and January 2018. Rainfall, temperature and RADPAR decreased below their averages by 5%, 0.3°C and 12%, respectively. At the sub-national scale, rainfall was significantly above average in Huanghuaihai, Inner Mongolia and Loess region whereas the Lower Yangtze and South-West China experienced the largest deficits (table 4.1). Rainfall was close to average in North East China and Southern China.

The spatial distribution of rainfall profiles shows that the variable was relatively stable and close to average for 62.2% of cropping areas of China, mainly located in the northeast and southwest part of the country (figure 4.1). The Loess region and some parts of Huanghuaihai and Southwest China (accounting for 28.9% of planted areas) experienced above-average rainfall up to October but close to average from November. On the contrary, 8.9% of croplands distributed in the southeast were generally below average during the whole monitoring period except for early January when significant above average (+90mm) precipitation was recorded, mostly as snow. During the reporting period, temperature was slightly below average in all regions, with departures ranging between -0.7 °C and -0.2°C. Temperature fluctuated largely  as indicated by figure 4.2 and table 4.1. Similar to temperature, RADPAR was also below average in all parts of China, with the departures between -4% and a very significant and potentially harmful -18% in the Lower Yangtze region.

BIOMSS increased by 7% while CALF declined by 3% compared to average. BIOMSS was above average in almost all sub-national regions of China except in Lower Yangtze region and Southwest China. In contrast, CALF was below average in most regions of China except in Loess region. As shown by figure 4.3, the uncropped arable lands are mainly located in the northern parts of Gansu and Shaanxi province, Shanxi province, Hebei province, central and southern Henan province, and northern Anhui province. Cropped areas include essentially the winter crop areas. The VCIx map shows that low values of this indicator (0.5-0.8) occurred in Northeast China, Inner Mongolia, the Loess region and Huanghuaihai, and Xinjiang province. Interestingly, the lowest values ( below 0.5) occur in southern Henan and northern Anhui provinces because the planted areas were covered by snow in January, which is confirmed with the CALF pattern (figure 4.3).Values larger than 0.8 occur in other parts of China and follow a pattern that is highly consistent with those of uncropped and cropped arable land. 

Table 4.1. CropWatch agroclimatic and agronomic indicators for China, October 2017-January 2018, departure from 5YAand 15YA

Figure 4.1. China spatial distribution of rainfall profiles, October 2017-January 2018 

Figure 4.2. China spatial distribution of temperature profiles, October 2017-January 2018

Figure 4.3 Cropped and uncropped arable land by pixel for winter crops producing provinces, October 2017-January 2018

Figure 4.4. China maximum Vegetation Condition Index (VCIx), by pixel, October 2017-January 2018