ENSO exacerbated the impact of compound dry–hot events on maize yield over China during 1961–2020

Abstract

Increasing compound dry and hot events (CDHEs) have become a leading risk to regional and global crop production. While numerous accounts of crop growth or yield response to climate extremes exist, impacts of CDHEs on crop yield are not well quantified, especially for that associated with large-scale modes of climate variabilities. Here we address this issue by using statistical maize yield data over China with a special focus on the impact of El Niño–Southern Oscillation (ENSO). We find that over 1961–2020, CDHEs led to significant yield reduction by 4 %, while it was aggravated to 6 % by the concurrent ENSO. Mechanisms for this underscored the role of ENSO in modulating CDHE characteristics wherein land–atmosphere feedbacks significantly contributed to yield loss. Compared to early stage of growth, ENSO in conjunction with compound events triggered more substantial maize yield losses during the late stage. Furthermore, this amplified risk was observed to intensify in recent decades. Note that agronomic practices, like irrigation, could significantly offset these negative impacts on maize yield. These findings highlight the great threat of CDHEs to maize yield as well as the key role of ENSO in driving this process, and may offer insights for yield prediction and agricultural management.