After a brief overview of the agro-climatic and agronomic conditions in China over the reporting period (section 4.1), Chapter 4 describes the situation by region, focusing on the seven most productive agro-ecological zones (AEZs) of the east and south (4.2): North-east China, Inner Mongolia, Huanghuaihai, Loess region, Lower Yangtze, Southwest China, and Southern China. Additional information on the agro-climatic indicators for agriculturally important Chinese provinces are listed in table A.11 in Annex A.

4.1 Overview

Agro-climatic conditions were generally below average in China from October 2018 to January 2019, with rainfall and radiation  deficits of 7% and 6%, respectively. Temperature was average at 6.8℃. Low rainfall and temperature resulted in a 1% drop of potential biomass. Due to the large diversity of climatic zones in China, weather conditions over different agro-ecological zones or different agriculturally important provinces differ much. Inner Mongolia, Loess region, North-east China and Southwest China suffered from water shortage, with 42%, 18%, 34% and 18% lower rainfall compared to average. Low rainfall will potentially hamper the sowing and early growth of crops after winter. Temperature in Inner Mongolia and North-east China were 0.7℃ and 2.4℃ above average. Below average RADPAR needs to be highlighted in several regions, especially in the Lower Yangtze (-15%), Southern China (-8%) and South-west China (-7%). Even if potential biomass is a synthetic indicator taking into account rainfall and temperature, patterns of biomass departures from average present same pattern of rainfall departures over all the AEZs.

Rainfall departure clustering and temperature departure clustering show detailed spatial and temporal patterns. Rainfall was generally below average across China during the monitoring period except for Yunnan and western Guizhou in early January and an ellipse-shaped areas from Guangxi to Southern Jiangsu in early December. Interestingly, temperature is globally below average in most of China above average in the provinces of the North-east which are the coldest in the country. This behavior exists across other Central Asian areas and is compatible with climate change projections; in other words: it is likely to persist in future seasons.

Other Provinces with large rainfall anomalies include Hebei (-45%), Ningxia (47%), Yunnan (50%) and Shandong (55%). The largest positive temperature anomalies (in excess of 1.0°C) were recorded in Inner Mongolia, Heilongjiang, Jilin and Liaoning. If the above average temperature continue into the next monitoring period (January to April), early snow melt and spring sowing dates are likely.

Table 4.1. CropWatch agroclimatic and agronomic indicators for China, October 2018-January 2019, departure from 5YA and 15YA

Figure 4.1. China crop phenology

Figure 4.2. China spatial distribution of rainfall profiles, October 2018-January 2019

Figure 4.3. China spatial distribution of temperature profiles, October 2018-January 2019

Figure 4.4. China maximum Vegetation Condition Index (VCIx), by pixel, October 2018-January 2019

Figure 4.5 Cropped and uncropped arable land by pixel for winter crops producing provinces, October 2018-January 2019